Podcasts about Arrhenius

My fellow pro-growth/progress/abundance Up Wingers,Global population growth is slowing, and it's not showing any signs of recovery. To the environmentalists of the 1970s, this may have seemed like a movement in the right direction. The drawbacks to population decline, however, are severe and numerous, and they're not all obvious.Today on Faster, Please! — The Podcast, I talk with economist and demographer Dean Spears about the depopulation trend that is transcending cultural barriers and ushering in a new global reality. We discuss the costs to the economy and human progress, and the inherent value of more people.Spears is an associate professor of economics at Princeton University where he studies demography and development. He is also the founding executive director of r.i.c.e., a nonprofit research organization seeking to uplift children in rural northern India. He is a co-author with Michael Geruso of After the Spike: Population, Progress, and the Case for People.In This Episode* Where we're headed (1:32)* Pumping the breaks (5:41)* A pro-parenting culture (12:40)* A place for AI (19:13)* Preaching to the pro-natalist choir (23:40)* Quantity and quality of life (28:48)Below is a lightly edited transcript of our conversation. Where we're headed (1:32). . . two thirds of people now live in a country where the birth rate is below the two children per two adults level that would stabilize the population.Pethokoukis: Who are you and your co-author trying to persuade and what are you trying to persuade them of? Are you trying to persuade them that global depopulation is a real thing, that it's a problem? Are you trying to persuade them to have more kids? Are you trying to persuade them to support a certain set of pro-child or pro-natalist policies?Spears: We are trying to persuade quite a lot of people of two important things: One is that global depopulation is the most likely future — and what global depopulation means is that every decade, every generation, the world's population will shrink. That's the path that we're on. We're on that path because birth rates are low and falling almost everywhere. It's one thing we're trying to persuade people of, that fact, and we're trying to persuade people to engage with a question of whether global depopulation is a future to welcome or whether we should want something else to happen. Should we let depopulation happen by default or could it be better to stabilize the global population at some appropriate level instead?We fundamentally think that this is a question that a much broader section of society, of policy discourse, of academia should be talking about. We shouldn't just be leaving this discussion to the population scientists, demographic experts, not only to the people who already are worried about, or talking about low birth rates, but this is important enough and unprecedented enough that everybody should be engaging in this question. Whatever your ongoing values or commitments, there's a place for you in this conversation.Is it your impression that the general public is aware of this phenomenon? Or are they still stuck in the '70s thinking that population is running amok and we'll have 30 billion people on this planet like was the scenario in the famous film, Soylent Green? I feel like the people I know are sort of aware that this is happening. I don't know what your experience is.I think it's changing fast. I think more and more people are aware that birth rates are falling. I don't think that people are broadly aware — because when you hear it in the news, you might hear that birth rates in the United States have fallen low or birth rates in South Korea have fallen low. I think what not everybody knows is that two thirds of people now live in a country where the birth rate is below the two children per two adults level that would stabilize the population.I think people don't know that the world's birth rate has fallen from an average around five in 1950 to about 2.3 today, and that it's still falling and that people just haven't engaged with the thought that there's no special reason to expect it to stop and hold it to. But the same processes that have been bringing birth rates down will continue to bring them down, and people don't know that there's no real automatic stabilizer to expect it to come back up. Of the 26 countries that have had the lifetime birth rate fall below 1.9, none of them have had it go back up to two.That's a lot of facts that are not as widely known as they should be, but then the implication of it, that if the world's birth rate goes below two and stays there, we're going to have depopulation generation after generation. I think for a lot of people, they're still in the mindset that depopulation is almost conceptually impossible, that either we're going to have population growth or something else like zero population growth like people might've talked about in the '70s. But the idea that a growth rate of zero is just a number and then that it's not going to stop there, it's going to go negative, I think that's something that a lot of people just haven't thought about.Pumping the breaks (5:41)We wrote this book because we hope that there will be an alternative to depopulation society will choose, but there's no reason to expect or believe that it's going happen automatically.You said there's no automatic stabilizers — at first take, that sounds like we're going to zero. Is there a point where the global population does hit a stability point?No, that's just the thing.So we're going to zero?Well, “there's no automatic stabilizer” isn't the same thing as “we're definitely going to zero.” It could be that society comes together and decides to support parenting, invest more in the next generation, invest more in parents and families, and do more to help people choose to be parents. We wrote this book because we hope that there will be an alternative to depopulation society will choose, but there's no reason to expect or believe that it's going happen automatically. In no country where the birth rate has gone to two has it just magically stopped and held there forever.I think a biologist might say that the desire to reproduce, that's an evolved drive, and even if right now we're choosing to have smaller families, that biological urge doesn't vanish. We've had population, fertility rates, rise and fall throughout history — don't you think that there is some sort of natural stabilizer?We've had fluctuations throughout history, but those fluctuations have been around a pretty long and pretty widely-shared downward trend. Americans might be mostly only now hearing about falling birth rates because the US was sort of anomalous amongst richer countries and having a relatively flat period from the 1970s to around 2010 or so, whereas birth rates were falling in other countries, they weren't falling in the US in the same way, but they were falling in the US before then, they're falling in the US since then, and when you plot it over the long history with other countries, it's clear that, for the world as a whole, as long as we've had records, not just for decades, but for centuries, we've seen birth rates be falling. It's not just a new thing, it's a very long-term trend.It's a very widely-shared trend because humans are unlike other animals in the important way that we make decisions. We have culture, we have rationality, we have irrationality, we have all of these. The reason the population grew is because we've learned how to keep ourselves and our children alive. We learned how to implement sanitation, implement antibiotics, implement vaccines, and so more of the children who were born survived even as the birth rate was falling all along. Other animals don't do that. Other animals don't invent sanitation systems and antibiotics and so I think that we can't just reason immediately from other animal populations to what's going to happen to humans.I think one can make a plausible case that, even if you think that this is a problem — and again, it's a global problem, or a global phenomenon, advanced countries, less-advanced countries — that it is a phenomenon of such sweep that if you're going to say we need to stabilize or slow down, that it would take a set of policies of equal sweep to counter it. Do those actually exist?No. Nobody has a turnkey solution. There's nothing shovel-ready here. In fact, it's too early to be talking about policy solutions or “here's my piece of legislation, here's what the government should do” because we're just not there yet, both in terms of the democratic process of people understanding the situation and there even being a consensus that stabilization, at some level, would be better than depopulation, nor are we there yet on having any sort of answer that we can honestly recommend as being tested and known to be something that will reliably stabilize the population.I think the place to start is by having conversations like this one where we get people to engage with the evidence, and engage with the question, and just sort of move beyond a reflexive welcoming of depopulation by default and start thinking about, well, what are the costs of people and what are the benefits of people? Would we be better off in a future that isn't depopulating over the long run?The only concrete step I can think of us taking right now is adapting the social safety net to a new demographic reality. Beyond that, it seems like there might have to be a cultural shift of some kind, like a large-scale religious revival. Or maybe we all become so rich that we have more time on our hands and decide to have more kids. But do you think at some point someone will have a concrete solution to bring global fertility back up to 2.1 or 2.2?Look at it like this: The UN projects that the peak will be about six decades from now in 2084. Of course, I don't have a crystal ball, I don't know that it's going to be 2084, but let's take that six-decades timeline seriously because we're not talking about something that's going to happen next year or even next decade.But six decades ago, people were aware that — or at least leading scientists and even some policymakers were aware that climate change was a challenge. The original computations by Arrhenius of the radiative forcing were long before that. You have the Johnson speech to Congress, you have Nixon and the EPA. People were talking about climate change as a challenge six decades ago, but if somebody had gotten on their equivalent of a podcast and said, “What we need to do is immediately get rid of the internal combustion engine,” they would've been rightly laughed out of the room because that would've been the wrong policy solution at that time. That would've been jumping to the wrong solution. Instead, what we needed to do was what we've done, which is the science, the research, the social change that we're now at a place where emissions per person in the US have been falling for 20 years and we have technologies — wind, and solar, and batteries — that didn't exist before because there have been decades of working on it.So similarly, over the next six decades, let's build the research, build the science, build the social movement, discover things we don't know, more social science, more awareness, and future people will know more than you and I do about what might be constructive responses to this challenge, but only if we start talking about it now. It's not a crisis to panic about and do the first thing that comes to mind. This is a call to be more thoughtful about the future.A pro-parenting culture (12:40)The world's becoming more similar in this important way that the difference across countries and difference across societies is getting smaller as birth rates converge downward.But to be clear, you would like people to have more kids.I would like for us to get on a path where more people who want to be parents have the sort of support, and environment, and communities they need to be able to choose that. I would like people to be thinking about all of this when they make their family decisions. I'd like the rest of us to be thinking about this when we pitch in and do more to help us. I don't think that anybody's necessarily making the wrong decision for themselves if they look around and think that parenting is not for them or having more children is not for them, but I think we might all be making a mistake if we're not doing more to support parents or to recognize the stake we have in the next generation.But all those sorts of individual decisions that seem right for an individual or for a couple, combined, might turn into a societal decision.Absolutely. I'm an economics professor. We call this “externalities,” where there are social benefits of something that are different from the private costs and benefits. If I decide that I want to drive and I contribute to traffic congestion, then that's an externality. At least in principle, we understand what to do about that: You share the cost, you share the benefits, you help the people internalize the social decision.It's tied up in the fact that we have a society where some people we think of as doing care work and some people we think of as doing important work. So we've loaded all of these costs of making the next generation on people during the years of their parenting and especially on women and mothers. It's understandable that, from a strictly economic point of view, somebody looks at that and thinks, “The private costs are greater than the private benefits. I'm not going to do that.” It's not my position to tell somebody that they're wrong about that. What you do in a situation like that is share and lighten that burden. If there's a social reason to solve traffic congestion, then you solve it with public policy over the long run. If the social benefits of there being a flourishing next generation are greater than people are finding in their own decision making, then we need to find the ways to invest in families, invest in parenting, lift and share those burdens so that people feel like they can choose to be parents.I would think there's a cultural component here. I am reminded of a book by Jonathan Last about this very issue in which he talks about Old Town Alexandria here in Virginia, how, if you go to Old Town, you can find lots of stores selling stuff for dogs, but if you want to buy a baby carriage, you can't find anything.Of course, that's an equilibrium outcome, but go on.If we see a young couple pushing a stroller down the street and inside they have a Chihuahua — as society, or you personally, would you see that and “Think that's wrong. That seems like a young couple living in a nice area, probably have plenty of dough, they can afford daycare, and yet they're still not going to have a kid and they're pushing a dog around a stroller?” Should we view that as something's gone wrong with our society?My own research is about India. My book's co-authored with Mike Geruso. He studies the United States more. I'm more of an expert on India.Paul Ehrlich, of course, begins his book, The Population Bomb, in India.Yes, I know. He starts with this feeling of being too crowded with too many people. I say in the book that I almost wonder if I know the exact spot where he has that experience. I think it's where one of my favorite shops are for buying scales and measuring tape for measuring the health of children in Uttar Pradesh. But I digress about Paul Ehrlich.India now, where Paul Ehrlich was worried about overpopulation, is now a society with an average birth rate below two kids per two adults. Even Uttar Pradesh, the big, disadvantaged, poor state where I do my work in research, the average young woman there says that they want an average of 1.9 children. This is a place where society and culture is pretty different from the United States. In the US, we're very accustomed to this story of work and family conflict, and career conflicts, especially for women, and that's probably very important in a lot of people's lives. But that's not what's going on in India where female labor force participation is pretty low. Or you hear questions about whether this is about the decline of religiosity, but India is a place where religion is still very important to a lot of people's lives. Marriage is almost universal. Marriage happens early. People start their childbearing careers in their early twenties, and you still see people having an average below two kids. They start childbearing young and they end childbearing young.Similarly, in Latin America, where religiosity, at least as reported in surveys, remains pretty high, but Latin America is at an average of 1.8, and it's not because people are delaying fertility until they're too old to get pregnant. You see a lot of people having permanent contraception surgery, tubal obligations.And so this cultural story where people aren't getting married, they're starting too late, they're putting careers first, it doesn't match the worldwide diversity. These diverse societies we're seeing are all converging towards low birth rates. The world's becoming more similar in this important way that the difference across countries and difference across societies is getting smaller as birth rates converge downward. So I don't think we can easily point towards any one cultural for this long-term and widely shared trend.A place for AI (19:13)If AI in the future is a compliment to what humans produce . . . if AI is making us more productive, then it's all the bigger loss to have fewer people.At least from an economic perspective, I think you can make the case: fewer people, less strain on resources, you're worried about workers, AI-powered robots are going to be doing a lot of work, and if you're worried about fewer scientists, the scientists we do have are going to have AI-powered research assistants.Which makes the scientists more important. Many technologies over history have been compliments to what humans do, not substitutes. If AI in the future is a compliment to what humans produce — scientific research or just the learning by doing that people do whenever they're engaging in an enterprise or trying to create something — if AI is making us more productive, then it's all the bigger loss to have fewer people.To me, the best of both worlds would be to have even more scientists plus AI. But isn't the fear of too few people causing a labor shortage sort of offset by AI and robotics? Maybe we'll have plenty of technology and capital to supply the workers we do have. If that's not the worry, maybe the worry is that the human experience is simply worse when there are fewer children around.You used the term “plenty of,” and I think that sort of assumes that there's a “good enough,” and I want to push back on that because I think what matters is to continue to make progress towards higher living standards, towards poverty alleviation, towards longer, better, healthier, safer, richer lives. What matters is whether we're making as much progress as we could towards an abundant, rich, safe, healthy future. I think we shouldn't let ourselves sloppily accept a concept of “good enough.” If we're not making the sort of progress that we could towards better lives, then that's a loss, and that matters for people all around the world.We're better off for living in a world with other people. Other people are win-win: Their lives are good for them and their lives are good for you. Part of that, as you say, is people on the supply side of the economy, people having the ideas and the realizations that then can get shared over and over again. The fact that ideas are this non-depletable resource that don't get used up but might never be discovered if there aren't people to discover them. That's one reason people are important on the supply side of the economy, but other people are also good for you on the demand side of the economy.This is very surprising because people think that other people are eating your slice of the pie, and if there are more other people, there's less for me. But you have to ask yourself, why does the pie exist in the first place? Why is it worth some baker's while to bake a pie that I could get a slice of? And that's because there were enough people wanting slices of pie to make it worth paying the fixed costs of having a bakery and baking a whole pie.In other words, you're made better off when other people want and need the same things that you want and need because that makes it more likely for it to exist. If you have some sort of specialized medical need and need specialized care, you're going to be more likely to find it in a city where there are more other people than in a less-populated rural place, and you're going to be more likely to find it in a course of history where there have been more other people who have had the same medical need that you do so that it's been worthwhile for some sort of cure to exist. The goodness of other people for you isn't just when they're creating things, it's also when they're just needing the same things that you do.And, of course, if you think that getting to live a good life is a good thing, that there's something valuable about being around to have good experiences, that a world of more people having good experiences has more goodness in it than a world of fewer people having good experiences in it. That's one thing that counts, and it's one important consideration for why a stabilized future might be better than a depopulating future. Now, I don't expect everyone to immediately agree with that, but I do think that the likelihood of depopulation should prompt us to ask that question.Preaching to the pro-natalist choir (23:40)If you are already persuaded listening to this, then go strike up a conversation with somebody.Now, listening to what you just said, which I thought was fantastic, you're a great explainer, that is wonderful stuff — but I couldn't help but think, as you explained that, that you end up spending a lot of time with people who, because they read the New York Times, they may understand that the '70s population fears aren't going to happen, that we're not going to have a population of 30 billion that we're going to hit, I don't know, 10 billion in the 2060s and then go down. And they think, “Well, that's great.”You have to spend a lot of time explaining to them about the potential downsides and why people are good, when like half the population in this country already gets it: “You say ‘depopulation,' you had us at the word, ‘depopulation.'” You have all these people who are on the right who already think that — a lot of people I know, they're there.Is your book an effective tool to build on that foundation who already think it's an issue, are open to policy ideas, does your book build on that or offer anything to those people?I think that, even if this is something that people have thought about before, a lot of how people have thought about it is in terms of pension plans, the government's budget, the age structure, the nearer-term balance of workers to retirees.There's plenty of people on the right who maybe they're aware of those things, but also think that it really is kind of a The Children of Men argument. They just think a world with more children is better. A world where the playgrounds are alive is better — and yes, that also may help us with social security, but there's a lot of people for whom you don't have to even make that economic argument. That seems to me that that would be a powerful team of evangelists — and I mean it in a nonreligious way — evangelists for your idea that population is declining and there are going to be some serious side effects.If you are already persuaded listening to this, then go strike up a conversation with somebody. That's what we want to have happen. I think minds are going to be changed in small batches on this one. So if you're somebody who already thinks this way, then I encourage you to go out there and start a conversation. I think not everybody, even people who think about population for a living — for example, one of the things that we engage with in the book is the philosophy of population ethics, or population in social welfare as economists might talk about it.There have been big debates there over should we care about average wellbeing? Should we care about total wellbeing? Part of what we're trying to say in the book is, one, we think that some of those debates have been misplaced or are asking what we don't think are the right questions, but also to draw people to what we can learn from thinking of where questions like this agree. Because this whole question of should we make the future better in total or make the better on average is sort of presuming this Ehrlich-style mindset that if the future is more populous, then it must be worse for each. But once you see that a future that's more populous is also more prosperous, it'd be better in total and better on average, then a lot of these debates might still have academic interest, but both ways of thinking about what would be a better future agree.So there are these pockets of people out there who have thought about this before, and part of what we're trying to do is bring them together in a unified conversation where we're talking about the climate modeling, we're talking about the economics, we're talking about the philosophy, we're talking about the importance of gender equity and reproductive freedom, and showing that you can think and care about all of these things and still think that a stabilized future might be better than depopulation.In the think tank world, the dream is to have an idea and then some presidential candidate adopts the idea and pushes it forward. There's a decent chance that the 2028 Republican nominee is already really worried about this issue, maybe someone like JD Vance. Wouldn't that be helpful for you?I've never spoken with JD Vance, but from my point of view, I would also be excited for India's population to stabilize and not depopulate. I don't see this as an “America First” issue because it isn't an America First issue. It's a worldwide, broadly-shared phenomenon. I think that no one country is going to be able to solve this all on its own because, if nothing else, people move, people immigrate, societies influence one another. I think it's really a broadly-shared issue.Quantity and quality of life (28:48)What I do feel confident about is that some stabilized size would be better than depopulation generation after generation, after generation, after generation, without any sort of leveling out, and I think that's the plan that we're on by default.Can you imagine an earth of 10 to 12 billion people at a sustained level being a great place to live, where everybody is doing far better than they are today, the poorest countries are doing better — can you imagine that scenario? Can you also imagine a scenario where we have a world of three to four billion, which is a way nicer place to live for everybody than it is today? Can both those scenarios happen?I don't see any reason to think that either of those couldn't be an equilibrium, depending on all the various policy choices and all the various . . .This is a very broad question.Exactly. I think it's way beyond the social science, economics, climate science we have right now to say “three billion is the optimal size, 10 billion is the optimal size, eight billion is the optimal size.” What I do feel confident about is that some stabilized size would be better than depopulation generation after generation, after generation, after generation, without any sort of leveling out, and I think that's the plan that we're on by default. That doesn't mean it's what's going to happen, I hope it's not what happens, and that's sort of the point of the conversation here to get more people to consider that.But let's say we were able to stabilize the population at 11 billion. That would be fine.It could be depending on what the people do.But I'm talking about a world of 11 billion, and I'm talking about a world where the average person in India is as wealthy as, let's say this is in the year 2080, 2090, and at minimum, the average person in India is as wealthy as the average American is today. So that's a big huge jump in wealth and, of course, environmentalism.And we make responsible environmental choices, whether that's wind, or solar, or nuclear, or whatever, I'm not going to be prescriptive on that, but I don't see any reason why not. My hope is that future people will know more about that question than I do. Ehrlich would've said that our present world of eight billion would be impossible, that we would've starved long before this, that England would've ceased to exist, I think is a prediction in his book somewhere.And there's more food per person on every continent. Even in the couple decades that I've been going to India, children are taller than they used to be, on average. You can measure it, and maybe I'm fooling myself, but I feel like I can see it. Even as the world's been growing more populous, people have been getting better off, poverty has been going down, the absolute number of people in extreme poverty has been going down, even as the world's been getting more populous. As I say, emissions per person have been going down in a lot of places.I don't see any in principle, reason, if people make the right decisions, that we couldn't have a sustainable, healthy, and good, large sustained population. I've got two kids and they didn't add to the hole in the ozone layer, which I would've heard about in school as a big problem in the '80s. They didn't add to acid rain. Why not? Because the hole in the ozone layer was confronted with the Montreal Protocol. The acid rain was confronted with the Clean Air Act. 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But what about the machine? - Ars* 'Invasion' Season 3 showrunner Simon Kinberg on creating ''War of the Worlds' meets 'Babel'' (exclusive) - Space▶ Up Wing/Down Wing* The era of the public apology is ending - Axios* Warren Brodey, 101, Dies; a Visionary at the Dawn of the Information Age - NYT* Reality is evil - Aeon* The Case for Crazy Philanthropy - Palladium▶ Substacks/Newsletters* Claude Code is growing crazy fast, and it's not just for writing code - AI Supremacy* No, ‘the Economists' Didn't Botch Trump's Tariffs - The Dispatch* How Does the US Use Water? - Construction Physics* A Climate-Related Financial Risk Boondoggle - The Ecomodernist* What's up with the States? - Hyperdimensional▶ Social Media* On why AI won't take all the jobs - @Dan_Jeffries1* On four nuclear reactors to be built in Amarillo, TX - @NuclearHazelnut* On AI welfare and consciousness - @sebkrier Faster, Please! is a reader-supported publication. 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Han hade ett finger med i varenda spel i Sverige, vare sig det gällde inrikespolitik eller forskning, säger författaren Jan Malmborg som skrivit den nya biografin Svante Arrhenius : nobelpristagare, kosmopolit och klimatpionjär. Lyssna på alla avsnitt i Sveriges Radio Play. Programmet sändes första gången 3/4 2025.Svante Arrhenius (1859-1927) var Sveriges ledande forskare kring förra sekelskiftet och 1903 blev han också Sveriges förste nobelpristagare. Han förknippas idag främst med att ha påvisat växthuseffekten men han forskade framförallt kring elektricitet.Våren 2025 kom den första stora boken om Arrhenius som är en historia om en stridbar och folklig forskare som efter en kämpig start på karriären blev en av Sveriges mäktigaste och mest kända personer. Och en globalt känd forskare, som inte minst i nobelsammanhang hade en mycket stark ställning i flera decennier.Medverkar gör bokens författare Jan Malmborg samt Agnes Wold, professor i klinisk bakteriologi och dotterdotter till Svante Arrhenius. Programledare:Mats Carlsson-Lenart mats.carlsson-lenart@sverigesradio.seProducent:Lars Broströmlars.brostrom@sverigesradio.se

Struggling to keep all the rate-law rules and enzyme facts straight? In this Jack Westin MCAT Podcast episode, Mike and Molly break down exactly what the AAMC expects you to know—no fluff, just high-yield kinetics you'll see on Test Day.What we cover in Part 1* Big-picture difference between K (equilibrium) vs k (rate)* The Arrhenius equation & how Ea and T really control reaction speed* How to recognize zeroth, first & second-order rate laws in passages* Why the rate-determining step rules every multi-step mechanism* How enzymes lower activation energy, plus active site basics* Essential vocab: apoenzyme → holoenzyme, cofactors vs coenzymes* The Induced-Fit Model (forget “lock-and-key” oversimplifications)* Fast recall with the LIL HOT enzyme-classification mnemonicBy the end you'll be able to:✅ Write and manipulate rate laws with confidence✅ Predict how temp or catalysts shift reaction speed✅ Decode enzyme names on the fly and spot catalytic tricks the MCAT lovesNext up in Part 2: Michaelis–Menten kinetics, Km/Vmax shortcuts, and inhibitor patterns—so make sure you're subscribed and turn on notifications!Want to learn more? Shoot us a text at 415-855-4435 or email us at podcast@jackwestin.com!

You can memorize every formula in the Kaplan book and STILL miss those sneaky MCAT acid–base questions. Let's fix that. In this episode of the Jack Westin MCAT Podcast, Mike & Molly walk you from first-semester chem definitions all the way to high-yield clinical tie-ins—so you understand (not just memorize) acids and bases.

Han hade ett finger med i varenda spel i Sverige, vare sig det gällde inrikespolitik eller forskning, säger författaren Jan Malmborg som skrivit den nya biografin Svante Arrhenius : nobelpristagare, kosmopolit och klimatpionjär Lyssna på alla avsnitt i Sveriges Radio Play. Svante Arrhenius (1859-1927) var Sveriges ledande forskare kring förra sekelskiftet och 1903 blev han också Sveriges förste nobelpristagare. Han förknippas idag främst med att ha påvisat växthuseffekten men han forskade framförallt kring elektricitet.Nu kommer den första stora boken om Arrhenius som är en historia om en stridbar och folklig forskare som efter en kämpig start på karriären blev en av Sveriges mäktigaste och mest kända personer. Och en globalt känd forskare, som inte minst i nobelsammanhang hade en mycket stark ställning i flera decennier.Medverkar gör bokens författare Jan Malmborg samt Agnes Wold, professor i klinisk bakteriologi och dotterdotter till Svante Arrhenius. Programledare:Mats Carlsson-Lenart mats.carlsson-lenart@sverigesradio.seProducent:Lars Broströmlars.brostrom@sverigesradio.se

Chemistry 222 Video Lecture from March 3, 2025. This video covers material from Chapter 12 including the Arrhenius equation, mechanisms, the rate determining step (rds), elementary reactions, and more. CH 222 website: http://mhchem.org/222 Let me know if you have any questions! Peace!

Når bør du begynne å lese for barn, og hvilke bøker er de beste for de aller minste? Sølvbergets formidlere trekker fram seks av sine favorittbøker for aldersgruppen 0-2 år. (00:00) Boktips for de aller minste (09:54) Lese eller fortelle? (11:15) Slik skaper du en god lesestund (15:44) Boktips: Emma og Thomas-serien av Gunilla Wolde (18:00) Boktips: Dyrene i Afrika av Thorbjørn Egner (19:44) Boktips: Nora-serien av Irene Marienborg (20:49) Boktips: Dyr på gården (24:30) Boktips: Julia-serien av Eva Eriksson og Lisa Moroni (26:13) Boktips: Mine første ord - inspirert av Edvard Munch av Ingela P. Arrhenius (29:11) Derfor bør du lese for barna --- Innspilt på Sølvberget bibliotek og kulturhus i februar 2025. Medvirkende: Rebekka Hennum, Linn-Therese Johansen Ognedal og Åsmund Ådnøy. Produksjon: Åsmund Ådnøy

Für diese Folge sprachen wir mit dem Ozeanologen und Klimaforscher Prof. Dr. Mojib Latif. Er ist Präsident der Akademie der Wissenschaften in Hamburg sowie Seniorprofessor am GEOMAR Helmholtz-Zentrum für Ozeanforschung Kiel und der Christian-Albrechts-Universität zu Kiel. Wir wollten mit ihm einen Blick in die Geschichte der Klimaforschung werfen, seine Reaktion auf die Zeitungsartikel unseres Podcast, die sich mit der Endlichkeit und Bedrohungen der natürlichen Lebensgrundlagen beschäftigen, einfangen, um dann natürlich wieder im Jetzt und der Zukunft anzukommen.

Welkom! Dit is het 3e seizoen van de PrentenboekenCast, een podcast over mooie, grappige en/of ontroerende prenten- en versjesboeken die je voor kunt lezen.In dit derde podcast seizoen bespreken we om de week prenten- en versjesboeken; de ene week voor baby, dreumes en peuter (0 t/m 3 jaar). De volgende aflevering schenken we aandacht aan prenten-en versjesboeken voor peuter en kleuter (3 t/m 6+ jaar). In deze volgorde blijven de afleveringen elkaar afwisselen.Deze aflevering zijn de baby-, dreumes-, peuterboeken weer aan de beurt. We bespreken onder andere de vijf genomineerde babyboekjes waarop tot 1 november 2024 gestemd kan worden om hét Babyboek van het jaar te worden. Over deze genomineerde babyboekjes gaan we in gesprek met Karin Buik, zij heeft meerdere jaren ervaring als BoekStartcoach op diverse consultatiebureaus én is tevens oma van een 9 maanden oude baby (kleindochter). Aanvullend bespreken we ook een tweetalig dreumesboek en twee ontzettend leuke, grappige, interactieve peuterboeken.Dit zijn de boeken die in deze aflevering de revue passeren, zijn: De vijf genomineerde Babyboekjes: - KNUFFELBEESTJE van Ingela P. Arrhenius,                 uitgeverij Gottmer, 2024- REGENBOOGRIF van Kathryn Jewitt met illustraties van Tracey English, uitgeverij De Vier Windstreken, 2023 - SLAAP ZACHT van Inge Rylant, uitgeverij Pelckmans, 2024 - IK MAAK MUZIEK van Lizzy Doyle, Standaarduitgeverij / Oogappel 2023 - HIGH FIVE! IN THE JUNGLE van Jess Hitchman met illustraties van Carole Aufranc, Standaarduitgeverij/ Oogappel, 2024Dreumesboek: RUPSJE NOOITGENOEG 100 EERSTE WOORDJES – een TWEETALIG boek- Eric Carle, uitgeverij Gottmer, 2024 verkrijgbaar in NL-Arabisch; NL-Engels; NL- Pools; NL-TurksPeuterboeken: LAAT MAAR DICHT! Van Ralf Butschkow, vertaald door Mark Haayema, uitgeverij Volt, 2024PAK DE BAL! Van Susanne Strasser, uitgeverij Hoogland & van Klaveren, 2024Ook dit seizoen werken we samen met @silversterkinderenjeugdboeken en willen hen bedanken voor de fijne samenwerking en het beschikbaar stellen van nieuwe boeken om in onze podcast te kunnen bespreken.Tevens veel dank voor het beschikbaar stellen van de muzikale intermezzo's door Erik van Os (compositie) en Frans van der Meer (productie).Veel luister- én voorleesplezier gewenst!Volg ons ook via: https://www.instagram.com/prentenboekencast/

A is for Arrhenius - Who? What? We start our trip through the alphabet as we have 28 days (and change) to the U.S. election. Swedish scientist, Svante Arrhenius, starting in 1894, constructed the first climate model which showed the effects that CO2 has on the atmosphere. It's a good place to start as everything on and enveloping earth connects to carbon. And Christ, "through who all things were made" is there in the midst of the "building blocks" that are carbon connected molecules. --- Support this podcast: https://podcasters.spotify.com/pod/show/presence/support

Why stop emitting when we can just plant a bunch of trees?BONUS EPISODES available on Patreon (https://www.patreon.com/deniersplaybook) SOCIALS & MORE (https://linktr.ee/deniersplaybook) CREDITS Created by: Rollie Williams, Nicole Conlan & Ben BoultHosts: Rollie Williams & Nicole ConlanExecutive Producer: Ben Boult Post-production: Jubilaria Media Researchers: Carly Rizzuto, Canute Haroldson & James Crugnale Art: Jordan Doll Music: Tony Domenick Special thanks: The Civil Liberties Defense Center, Shelley Vinyard & The National Resources Defense Council, Angeline Robertson & Stand.EarthSOURCESMrBeast. (2019). Planting 20,000,000 Trees, My Biggest Project Ever! YouTube.Charmin. (2022, January 31). Protect Grow Restore | Charmin® Loves Trees. YouTube.CNBC Television. (2020, January 21). Watch President Donald Trump's full speech at the Davos World Economic Forum. YouTube.Carrington, D. (2019, July 4). Tree planting “has mind-blowing potential” to tackle climate crisis. The Guardian.Jordan, A., Vinyard, S., & Skene, J. (2024). Issue with the Tissue. NRDC.Lee, S.-C., & Han, N. (n.d.). Unasylva - Vol. 2, No. 6 - Forestry in China. Food and Agriculture Organization of the United Nations.The Green Belt Movement. (2021, March 3). Wangari Maathai on the origins of The Green Belt Movement. Facebook.MacDonald, M. (2005, March 26). The Green Belt Movement, and the Story of Wangari Maathai. YES! Magazine.What We Do. (2024). The Green Belt Movement.Nobel Peace Center. (2022, February 25). Wangari Maathai: the Nobel Peace Prize Laureate Who Planted Trees.Campaign to plant a billion trees within a year launched at UN climate change conference. (2006, November 8). UN News: Global Perspective Human Stories.U. N. Environment Programme. (2008, September 10). Plant for the Planet: The Billion Tree Campaign. UNEP.Christophersen, T. (n.d.). The Climate Leadership That Inspires Me: Felix Finkbeiner. UNEP.Plant-for-the-Planet – Trillion Trees for Climate Justice. (2024). Plant-For-The-Planet.Plant-for-the-Planet: Growing A Greener Future. (2011, February 7). Children call at the UN for a common fight for their future - Felix Finkbeiner is speaking(en,fr,de). YouTube.Felix Finkbeiner. (2023, December 30). Wikipedia.Rienhardt, J. (2021, April 28). “Plant for the Planet”: Spendengelder versenkt? Zweifel an Stiftung wachsen. Stern.Lang, C. (2021, October 8). A trillion trees: A backstory featuring Felix Finkbeiner and Thomas Crowther. Substack; REDD-Monitor.Popkin, G. (2019, October 24). Catchy findings have propelled this young ecologist to fame—and enraged his critics. Science.Crowther, T. W., Glick, H. B., Covey, K. R., Bettigole, C., Maynard, D. S., Thomas, S. M., Smith, J. R., Hintler, G., Duguid, M. C., Amatulli, G., Tuanmu, M.-N. ., Jetz, W., Salas, C., Stam, C., Piotto, D., Tavani, R., Green, S., Bruce, G., Williams, S. J., & Wiser, S. K. (2015). Mapping tree density at a global scale. Nature, 525(7568), 201–205. https://doi.org/10.1038/nature14967Bastin, J.-F., Finegold, Y., Garcia, C., Mollicone, D., Rezende, M., Routh, D., Zohner, C. M., & Crowther, T. W. (2019). The global tree restoration potential. Science, 365(6448), 76–79.St. George, Z. (2022, July 13). Can Planting a Trillion New Trees Save the World? The New York Times.Pomeroy, R. (2020, January 22). One trillion trees - uniting the world to save forests and climate. World Economic Forum.Guarino, B. (2020, January 22). The audacious effort to reforest the planet. Washington Post.FAQs. (2024). 1t.org.The Partnership. (n.d.). Trillion Trees.Ballew, M., Carman, J., Rosenthal, S., Verner, M., Kotcher, J., Maibach, E., & Leiserowitz, A. (2023, October 26). Which Republicans are worried about global warming? Yale Program on Climate Change Communication; Yale School of the Environment.Kennedy, B., & Tyson, A. (2024, March 1). How Republicans view climate change and energy issues. Pew Research Center.Roll Call. (2020, March 11). Is the GOP warming to climate action? Trillion trees plan hopes for growth. YouTube.Speaker Kevin McCarthy. (2023, June 29). Speaker McCarthy and House Republicans Fight For American-Made Energy in Columbiana County, Ohio. YouTube.Sen. Mike Braun - Indiana. (2024). Open SecretsRep. Buddy Carter - Georgia (District 01). (2024). Open Secrets.Rep. Kevin McCarthy - California (District 23). (2024). Open Secrets.Rep. Clay Higgins - Louisiana (District 03). (2024). Open Secrets.Rep. Bruce Westerman - Arkansas (District 04). (2024). Open Secrets.Actions - H.R.2639 - 117th Congress (2021-2022): Trillion Trees Act. (n.d.). Congress.gov.2023 National ECongress.govnvironmental Scorecard. (2023). League of Conservation Voters.Heal, A. (2023, April 11). The illusion of a trillion trees. The Financial Times Limited.Veldman, J. W., Aleman, J. C., Alvarado, S. T., Anderson, T. M., Archibald, S., Bond, W. J., Boutton, T. W., Buchmann, N., Buisson, E., Canadell, J. G., Dechoum, M. de S., Diaz-Toribio, M. H., Durigan, G., Ewel, J. J., Fernandes, G. W., Fidelis, A., Fleischman, F., Good, S. P., Griffith, D. M., & Hermann, J.-M. (2019). Comment on “The global tree restoration potential.” Science, 366(6463). https://doi.org/10.1126/science.aay7976.Erratum for the Report: “The global tree restoration potential” by J.-F. Bastin, Y. Finegold, C. Garcia, D. Mollicone, M. Rezende, D. Routh, C. M. Zohner, T. W. Crowther and for the Technical Response “Response to Comments on ‘The global tree restoration potential'” by J.-F. Bastin, Y. Finegold, C. Garcia, N. Gellie, A. Lowe, D. Mollicone, M. Rezende, D. Routh, M. Sacande, B. Sparrow, C. M. Zohner, T. W. Crowther. (2020). Science, 368(6494). https://doi.org/10.1126/science.abc8905Anderson, T. R., Hawkins, E., & Jones, P. D. (2016). CO2, the greenhouse effect and global warming: from the pioneering work of Arrhenius and Callendar to today's Earth System Models. Endeavour, 40(3), 178–187. https://doi.org/10.1016/j.endeavour.2016.07.002Hasler, N., Williams, C. A., Vanessa Carrasco Denney, Ellis, P. W., Shrestha, S., Terasaki, D. E., Wolff, N. H., Yeo, S., Crowther, T. W., Werden, L. K., & Cook-Patton, S. C. (2024). Accounting for albedo change to identify climate-positive tree cover restoration. Nature Communications, 15. https://doi.org/10.1038/s41467-024-46577-1Viani, R. A. G., Bracale, H., & Taffarello, D. (2019). Lessons Learned from the Water Producer Project in the Atlantic Forest, Brazil. Forests, 10(11), 1031. https://doi.org/10.3390/f10111031Vadell, E., de-Miguel, S., & Pemán, J. (2016). Large-scale reforestation and afforestation policy in Spain: A historical review of its underlying ecological, socioeconomic and political dynamics. Land Use Policy, 55, 37–48. https://doi.org/10.1016/j.landusepol.2016.03.017TED-Ed. (2023, December 19). Does planting trees actually cool the planet? - Carolyn Beans. YouTube.Howard, S. Q.-I., Emma, & Howard, E. (2022, December 12). “How are we going to live?” Families dispossessed of their land to make way for Total's Congo offsetting project. Unearthed.Garside, R., & Wyn, I. (2021, August 6). Tree-planting: Why are large investment firms buying Welsh farms? BBC News.Gabbatiss, J., & Viisainen, V. (2024, June 26). Analysis: UK misses tree-planting targets by forest the “size of Birmingham.” Carbon Brief.Buller, A. (2022). The Value of a Whale. Manchester University Press.Alexander, S. (2024, May 3). A Billionaire Wanted to Save 1 Trillion Trees by 2030. It's Not Going Great. Bloomberg.No Watermark Clips. (2019, May 21). King of the Hill on Carbon Offsets. YouTube.Choi-Schagrin, W. (2021, August 23). Wildfires are ravaging forests set aside to soak up greenhouse gases. The New York Times.Hodgson, C. (2021, August 4). US Forest Fires Threaten Carbon Offsets as Company-Linked Trees Burn. Inside Climate News.What's the potential of a trillion trees? (2020). Crowther Lab.Luhn, A. (2023, December 13). Stop Planting Trees, Says Guy Who Inspired World to Plant a Trillion Trees. Wired.TED Audio Collective. (2022, July 3). Can planting trees really stop climate change? | Thomas Crowther | The TED Interview. YouTube.Fleischman, F., Basant, S., Chhatre, A., Coleman, E. A., Fischer, H. W., Gupta, D., Güneralp, B., Kashwan, P., Khatri, D., Muscarella, R., Powers, J. S., Ramprasad, V., Rana, P., Solorzano, C. R., & Veldman, J. W. (2020). Pitfalls of Tree Planting Show Why We Need People-Centered Natural Climate Solutions. BioScience, 70(11). https://doi.org/10.1093/biosci/biaa094Oglesby, C. (2021, Feb 9). Republicans want to plant 1 trillion trees — and then log them. GristCORRECTIONSFelix Finkbeiner was 13 years old when he spoke at the United Nations, not 12.The industry that has currently contributed the most to Rep. Bruce Westerman's career campaigns for federal congress is the Forestry & Forest Products industry, as reported by Open Secrets. The Oil & Gas industry is listed as #2.DISCLAIMER: Some media clips have been edited for length and clarity.[For sponsorship inquiries, please contact climatetown@no-logo.co]See Privacy Policy at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.

Why is PoF so Hard? Abstract Chris and Fred discuss why the Physics of Failure (PoF) is hard to model? … or is it? Key Points Join Chris and Fred as they discuss how the Physics of Failure (PoF) is seen as hard to use to model time to failure of something. It usually needs […] The post SOR 966 Why is PoF so Hard? appeared first on Accendo Reliability.

Welcome to The Nonlinear Library, where we use Text-to-Speech software to convert the best writing from the Rationalist and EA communities into audio. This is: So What's Up With PUFAs Chemically?, published by J Bostock on April 27, 2024 on LessWrong. This is exploratory investigation of a new-ish hypothesis, it is not intended to be a comprehensive review of the field or even a a full investigation of the hypothesis. I've always been skeptical of the seed-oil theory of obesity. Perhaps this is bad rationality on my part, but I've tended to retreat to the sniff test on issues as charged and confusing as diet. My response to the general seed-oil theory was basically "Really? Seeds and nuts? The things you just find growing on plants, and that our ancestors surely ate loads of?" But a twitter thread recently made me take another look at it, and since I have a lot of chemistry experience I thought I'd take a look. The PUFA Breakdown Theory It goes like this: PUFAs from nuts and seeds are fine. Deep-frying using PUFAs causes them to break down in a way other fatty acids do not, and these breakdown products are the problem. Most of a fatty acid is the "tail". This consists of hydrogen atoms decorating a backbone of carbon atoms. Each carbon atom can make up to four bonds, of which two have to be to other carbons (except the end carbon which only bonds to one carbon) leaving space for two hydrogens. When a chain has the maximum number of hydrogen atoms, we say it's "saturated". These tails have the general formula CnH2n+1: For a carbon which is saturated (i.e. has four single bonds) the bonds are arranged like the corners of a tetrahedron, and rotation around single bonds is permitted, meaning the overall assembly is like a floppy chain. Instead, we can have two adjacent carbons form a double bond, each forming one bond to hydrogen, two bonds to the adjacent carbon, and one to a different carbon: Unlike single bonds, double bonds are rigid, and if a carbon atom has a double bond, the three remaining bonds fall in a plane. This means there are two ways in which the rest of the chain can be laid out. If the carbons form a zig-zag S shape, this is a trans double bond. If they form a curved C shape, we have a cis double bond. The health dangers of trans-fatty acids have been known for a long while. They don't occur in nature (which is probably why they're so bad for us). Cis-fatty acids are very common though, especially in vegetable and, yes, seed oils. Of course there's no reason why we should stop at one double bond, we can just as easily have multiple. This gets us to the name poly-unsaturated fatty acids (PUFAs). I'll compare stearic acid (SA) oleic acid (OA) and linoleic acid (LA) for clarity: Linoleic acid is the one that seed oil enthusiasts are most interested in. We can go even further and look at α-linoleic acid, which has even more double bonds, but I think LA makes the point just fine. Three fatty acids, usually identical ones, attach to one glycerol molecule to form a triglyceride. Isomerization As I mentioned earlier, double bonds are rigid, so if you have a cis double bond, it stays that way. Mostly. In chemistry a reaction is never impossible, the components are just insufficiently hot. If we heat up a cis-fatty acid to a sufficient temperature, the molecules will be able to access enough energy to flip. The rate of reactions generally scales with temperature according to the Arrhenius equation: v=Aexp(EakBT) Where A is a general constant determining the speed, Ea is the "activation energy" of the reaction, T is temperature, and kB is a Boltzmann's constant which makes the units work out. Graphing this gives the following shape: Suffice to say this means that reaction speed can grow very rapidly with temperature at the "right" point on this graph. Why is this important? Well, trans-fatty acids are slightly lower energy than cis ones, so at a high enough temperature, we can see cis to trans isomerization, turning OA o...

Link to original articleWelcome to The Nonlinear Library, where we use Text-to-Speech software to convert the best writing from the Rationalist and EA communities into audio. This is: So What's Up With PUFAs Chemically?, published by J Bostock on April 27, 2024 on LessWrong. This is exploratory investigation of a new-ish hypothesis, it is not intended to be a comprehensive review of the field or even a a full investigation of the hypothesis. I've always been skeptical of the seed-oil theory of obesity. Perhaps this is bad rationality on my part, but I've tended to retreat to the sniff test on issues as charged and confusing as diet. My response to the general seed-oil theory was basically "Really? Seeds and nuts? The things you just find growing on plants, and that our ancestors surely ate loads of?" But a twitter thread recently made me take another look at it, and since I have a lot of chemistry experience I thought I'd take a look. The PUFA Breakdown Theory It goes like this: PUFAs from nuts and seeds are fine. Deep-frying using PUFAs causes them to break down in a way other fatty acids do not, and these breakdown products are the problem. Most of a fatty acid is the "tail". This consists of hydrogen atoms decorating a backbone of carbon atoms. Each carbon atom can make up to four bonds, of which two have to be to other carbons (except the end carbon which only bonds to one carbon) leaving space for two hydrogens. When a chain has the maximum number of hydrogen atoms, we say it's "saturated". These tails have the general formula CnH2n+1: For a carbon which is saturated (i.e. has four single bonds) the bonds are arranged like the corners of a tetrahedron, and rotation around single bonds is permitted, meaning the overall assembly is like a floppy chain. Instead, we can have two adjacent carbons form a double bond, each forming one bond to hydrogen, two bonds to the adjacent carbon, and one to a different carbon: Unlike single bonds, double bonds are rigid, and if a carbon atom has a double bond, the three remaining bonds fall in a plane. This means there are two ways in which the rest of the chain can be laid out. If the carbons form a zig-zag S shape, this is a trans double bond. If they form a curved C shape, we have a cis double bond. The health dangers of trans-fatty acids have been known for a long while. They don't occur in nature (which is probably why they're so bad for us). Cis-fatty acids are very common though, especially in vegetable and, yes, seed oils. Of course there's no reason why we should stop at one double bond, we can just as easily have multiple. This gets us to the name poly-unsaturated fatty acids (PUFAs). I'll compare stearic acid (SA) oleic acid (OA) and linoleic acid (LA) for clarity: Linoleic acid is the one that seed oil enthusiasts are most interested in. We can go even further and look at α-linoleic acid, which has even more double bonds, but I think LA makes the point just fine. Three fatty acids, usually identical ones, attach to one glycerol molecule to form a triglyceride. Isomerization As I mentioned earlier, double bonds are rigid, so if you have a cis double bond, it stays that way. Mostly. In chemistry a reaction is never impossible, the components are just insufficiently hot. If we heat up a cis-fatty acid to a sufficient temperature, the molecules will be able to access enough energy to flip. The rate of reactions generally scales with temperature according to the Arrhenius equation: v=Aexp(EakBT) Where A is a general constant determining the speed, Ea is the "activation energy" of the reaction, T is temperature, and kB is a Boltzmann's constant which makes the units work out. Graphing this gives the following shape: Suffice to say this means that reaction speed can grow very rapidly with temperature at the "right" point on this graph. Why is this important? Well, trans-fatty acids are slightly lower energy than cis ones, so at a high enough temperature, we can see cis to trans isomerization, turning OA o...

Chemistry 222 Video Lecture from March 4, 2024. This video covers material from Chapter 12 of our textbook including the mechanisms, energy of activation, the Arrhenius equation, the meaning of rate orders and the rate law, and more. CH 222 website: http://mhchem.org/222 Let me know if you have any questions! Peace!

rWotD Episode 2446: Acid–base reaction Welcome to random Wiki of the Day where we read the summary of a random Wikipedia page every day.The random article for Sunday, 14 January 2024 is Acid–base reaction.In chemistry, an acid–base reaction is a chemical reaction that occurs between an acid and a base. It can be used to determine pH via titration. Several theoretical frameworks provide alternative conceptions of the reaction mechanisms and their application in solving related problems; these are called the acid–base theories, for example, Brønsted–Lowry acid–base theory.Their importance becomes apparent in analyzing acid–base reactions for gaseous or liquid species, or when acid or base character may be somewhat less apparent. The first of these concepts was provided by the French chemist Antoine Lavoisier, around 1776. It is important to think of the acid–base reaction models as theories that complement each other. For example, the current Lewis model has the broadest definition of what an acid and base are, with the Brønsted–Lowry theory being a subset of what acids and bases are, and the Arrhenius theory being the most restrictive.This recording reflects the Wikipedia text as of 01:17 UTC on Sunday, 14 January 2024.For the full current version of the article, see Acid–base reaction on Wikipedia.This podcast uses content from Wikipedia under the Creative Commons Attribution-ShareAlike License.Visit our archives at wikioftheday.com and subscribe to stay updated on new episodes.Follow us on Mastodon at @wikioftheday@masto.ai.Also check out Curmudgeon's Corner, a current events podcast.Until next time, I'm Kimberly Neural.

Welkom bij de PrentenboekenCast, een podcast over prenten- en versjesboeken die je voor kunt lezen aan kinderen van 0 t/m 6 jaar. Deze aflevering gaat over de PRENTENBOEKEN TOP 10 die tijdens de Nationale Voorleesdagen leidend zijn. De Nationale voorleesdagen zijn van 24 januari t/m 3 februari 2024 en ieder jaar wordt een top 10 gekozen door een comité van boekhandelaren, docenten en bibliothecarissen. Dit jaar zijn de volgende 10 prentenboeken geselecteerd:1. 'S NACHTS ALS JIJ SLAAPT geschreven en geïllustreerd door Peter en Ingela P. Arrhenius, uitgeverij Gottmer, 2022 2. AAN ZEE van Noelle Smit, uitgeverij Querido, 2022 3. BEER ZOEKT EEN BESTE VRIEND van Petr Horacek, uitgeverij Lemniscaat, 2022 4. HET VERLEGEN VOGELTJE geschreven door Jan Paul Schutte met illustraties van Liset Celie, uitgeverij Gottmer, 2022 5. ARON EN AARDAPPEL geschreven door Josh Lacey en geillustreerd door Momoke Abe, uitgeverij Gottmer, 2022 6. IK MIS MILO geschreven door Pim Lammers en geïllustreerd door Sanne te Loo, uitgeverij Querido, 2022 7. FRED EN DE (BIJNA MISLUKTE) VERJAARDAG van Pepé Smit, uitgeverij De Harmonie, 2022 8. HET BOS VAN MUIS geschreven door William Snow en geïllustreerd door Alice Melvin, uitgeverij Christofoor, 2022 9. PIT van Maggi Li uitgeverij Ploegsma, 202210. HET PRENTENBOEK VAN HET JAAR 2024: HELP! EEN VERRASSING! van Miriam Bos, uitgeverij Lemniscaat, 2022Dit boek wordt, als prentenboek van het jaar, ook op de website: www.prentenboekeninalletalen.nl in zeer veel talen en dialecten voorgelezen.De muzikale intermezzo's, tijdens de podcastaflevering, zijn van Erik van Os (compositie) en Frans van de Meer (Productie)We willen Silvester Kinder- en Jeugdboeken uit Zoetermeer bedanken voor de samenwerking en beschikbaar stellen van nieuwe boeken om in onze podcast te kunnen bespreken.Veel luister- én voorleesplezier gewenst! Volg ons ook via: https://www.instagram.com/prentenboekencast/

Redan i slutet av 1800-talet förstod Svante Arrhenius att människan värmer upp jordklotet. Under ett år räknade han för hand och skapade världens första klimatmodell. Lyssna på alla avsnitt i Sveriges Radio Play. I serien Klimatinsikten från 2020 berättar vi historien om hur kunskapen om klimatförändringen växte fram. Första delen tar dig 200 år bakåt i tiden. Det var då forskare förstod att något i atmosfären håller kvar värme. Det som vi idag kallar växthuseffekten.Den svenske forskaren Svante Arrhenius var sedan först med att foga ihop kunskapen om klimatet till en teori, som står sig än idag. Men han var inte det minsta bekymrad över uppvärmningen – tvärt om välkomnade han den.I programmet medverkar Henning Rodhe, professor vid meteorologiska institutionen vid Stockholms universitet, och Sverker Sörlin, idéhistoriker och professor i miljöhistoria vid Kungliga tekniska högskolan.Programmet är en repris från 27 jan 2020.ProgramledareMalin AveniusProducentPeter Normarkpeter.normark@sverigesradio.seLjudteknikerOlof Sjöström

OpenAI's large-scale language-generation tool ChatGPT may have been used to draft some content in this episode and some of the show notes of this episode. StudySquare Ltd has adapted the content, and the publication is attributed to StudySquare Ltd. This episode is a general guideline for information and not a specific tutorial for any specific syllabus; therefore, it should not be relied upon. StudySquare Ltd and any people involved in producing this podcast take no responsibility or liability for any potential errors or omissions regarding this podcast and make no guarantees of any completeness, accuracy, or usefulness of the information contained in this podcast, its structure or its show notes. The problems or questions in this episode might not appear in exam papers.The content in this episode might be more relevant to learners in the United Kingdom. Laws, educational standards, and exam requirements may vary significantly from one location to another. It's the listener's responsibility to confirm that the material complies with the requirements and regulations of their local educational system. If any content of this episode does not comply with your local regulations or laws, please discontinue listening and consult with your local educational authorities.Any references to experiments in this episode are for information purposes only and do not allow any listener to perform them without proper guidance or support. Experiments or practical work mentioned during this episode should not be attempted without appropriate supervision from a qualified teacher or professional. Additionally, the information provided in our podcast is not medical advice and should not be taken as such. If you require medical advice, please consult a healthcare professional. This episode is provided 'as is' without any representations or warranties, express or implied.This episode covers the following:• Rate of reaction• Catalysts• Maxwell-Boltzmann distribution• Rate equation• Arrhenius equation• Page for this topic: https://studysquare.co.uk/test/Chemistry/Edexcel/A-level/Rate-of-reaction?s=p• Trial lesson (terms and conditions apply): https://www.studysquare.co.uk/trial?s=p-/test/Chemistry/Edexcel/A-level/Rate-of-reaction• Privacy policy of Spreaker (used to distribute this episode): https://www.spreaker.com/privacy

Is climate change an impending existential threat, or a serious but manageable problem we can tackle with innovation and human ingenuity? Zeke Hausfather joins this episode of Faster, Please! — The Podcast to explain the basics of climate modeling and give a clear-eyed assessment of the risks we face and the measures we can take.Zeke is a climate scientist and energy systems analyst. He is the climate research lead for Stripe and a research scientist at Berkeley Earth.In This Episode* Human impact on the climate (1:11)* Global temperature forecasting (6:33)* Low-probability, high-risk scenarios (15:07)* Reducing carbon emissions (17:06)* Carbon capture and carbon removal (25:25)Below is an edited transcript of our conversationFaster, Please! is a reader-supported publication. To receive new posts and support my work, consider becoming a free or paid subscriber. Thanks!Human impact on the climateJames Pethokoukis: How do we know that our planet is warming? And secondarily, how do we know the actions of people are playing a key role?Zeke Hausfather: That's a great question. In terms of how we know it's warming: We've been monitoring the Earth's climate with reasonably dense measurements since the mid-1800s. That's when groups like NASA, NOAA, the UK Hadley Centre, my own Berkeley Earth group, have been able to put together reliable global surface temperature estimates. And we've seen in the period…That's since the 1980s?1850.1850. NASA was not around in 1850.No. But enough measurements were being taken both at weather stations around the world and on ships in the oceans that we can reconstruct global temperatures with an accuracy of a couple tenths of a degree going back that far. We know that the world has warmed by about 1.2 degrees centigrade since 1850 with the vast majority of that warming, about 1 degree of it, happening since 1970. That isn't in much dispute in the scientific community at all. Now, going further back is harder, obviously. We only invented the thermometer in the early 1700s. There are a few locations on land that go back that far, but to go back further in time, we need to rely on what we call climate proxies: things like ice cores, tree rings, coral sediments, pollen in lakes — various natural factors that are in some way related to the temperature when those things occurred.Those have much higher uncertainties, of course, but we do know using those reconstructions that current temperature levels are probably unprecedented in at least the last 2000 years and are at the high end of anything we've seen in the last 120,000 years or so. Certainly if current temperatures were to stay at today's levels for another century, they'd be higher than anything we've seen in 120,000 years. But it's harder to precisely make those claims because the time resolution of these indirect proxy measurements is very coarse when we go back further in time. You might have one ice core measurement reflect a hundred-year average period, for example, rather than a specific year. We know from the temperature record that the world has warmed. How do we know that human activity is playing a role? Well, we've known since the mid-1800s, due to pioneering work by folks like John Tyndall or Arrhenius, that carbon dioxide is a greenhouse gas and that greenhouse gases like carbon dioxide, water vapor, methane are critical to maintain a habitable planet. Without greenhouse gases in our atmosphere, the Earth would be a snowball and life would probably not exist.We also know that the amount of carbon dioxide in the atmosphere has increased pretty dramatically. We have measurements from ice cores going back about 800,000 years of carbon dioxide in the atmosphere at a reasonably high resolution. And because carbon dioxide is well mixed, knowing it in one location in one ice core gives us a good picture of carbon dioxide for the whole planet. And we know that prior to the year 1850, carbon dioxide concentrations in the atmosphere varied between about 170 to 280 parts per million. They're lower during ice age periods; they're higher during warmer interglacial periods. But since the 1850s, that value has increased dramatically. The amount of carbon dioxide in the atmosphere has increased by about 50 percent. It's gone from 280 parts per million, which was over the last 10,000 years since the end of the last ice age, up to about 420 parts per million today.And that reflects a huge amount of carbon dioxide in the atmosphere. I don't think people realize quite the magnitude we're talking about. The amount of carbon dioxide that humans have added to the atmosphere by digging up stuff from underground and burning it is roughly equal in mass to the entire biosphere. We took every single bit of life on Earth and burned it. That was about how much CO2 we put up in the atmosphere since the Industrial Revolution. Or to put it another way, it's equal in mass to all of everything humans have ever built: the pyramids, every skyscraper, every road. We took all that mass and put it up into the atmosphere. That's the amount of CO2 we've emitted. And so that's had a pretty big effect on what we call the radiative forcing of our climate, essentially the amount of outgoing longwave radiation — or heat, in common parlance — that gets absorbed and reradiated back toward the surface. And the estimate…That's the key mechanism we're talking about here, right?Yeah. Sunlight comes in from the sun, which provides pretty much all the Earth's energy. It gets absorbed by the surface of the Earth and reradiated as heat. That heat goes back out to space. Ideally, those two things should be an equilibrium: The amount of energy entering the Earth system matches the amount that leaves the Earth system, and the Earth stays a happy, healthy temperature. What we've seen in the last century, and we can verify this over the last few decades directly through satellite observations, is the amount of heat entering the Earth system is larger than the amount of heat leaving the Earth system. So the Earth is out of thermal equilibrium and is heating up. Most of that heat is going into the oceans, about 90 percent of it. But about 10 percent of that heat that's trapped goes into the atmosphere, and that's responsible for the warming we've seen.The climate is a hugely complex system, and when you're trying to project the response of the climate to our emissions, you're dealing with a lot of uncertainty around what we call feedbacks in the climate system.Global temperature forecastingLooking forward, various climate models, which is what we use to forecast what's going to happen next, look at what we've already put into the atmosphere and what we're continuing to put into the atmosphere, and they make a forecast about how that will impact temperatures going forward. Do I have that part right?Yep.Okay. So based on what these models are saying, what is reasonable to expect in coming decades as far as temperature increases and their impacts?The amount of future warming we end up having depends largely on how much CO2 and other greenhouse gases we emit. If we keep emissions roughly at current levels for the rest of the century — we're emitting about 40 billion tons of CO2 per year — if we keep that steady, we don't increase it at all, we expect somewhere in the range of 3 degrees centigrade warming by the end of the century, so that would be a bit above 5 degrees Fahrenheit warming globally, relative to the pre-industrial period or 1850. We've already experienced 1.2 degrees C. We'd have another 1.8 degrees C or so on top of that by the end of the century. If we emit more, it could be higher than that. If we emit less, it could be lower than that.That said, that's sort of the average estimate across the 40 different modeling centers around the world that do these sort of exercises. In reality, the climate is a hugely complex system, and when you're trying to project the response of the climate to our emissions, you're dealing with a lot of uncertainty around what we call feedbacks in the climate system. As an example: As we warm the surface, we get more evaporation and the atmosphere can hold more water vapor before rain falls out as the air is warmer. This is a fairly well-known physical relationship. And so for every degree of warming, you get about 7 percent more water vapor in the atmosphere. Now, water vapor itself is a greenhouse gas, and so that enhances the warming the world experiences. Because it's warmer, that water vapor can stay in the atmosphere — because usually the water vapor itself is very, very short-lived and can't force the climate by itself because it just rains out if you get too much.There are also uncertainties in how clouds respond to our emissions. More water vapor in the atmosphere leads to more cloud formation in some regions. Higher temperatures and changing wind patterns lead to changing cloud dynamics. Our emissions of other things like aerosols, small particles from burning fossil fuels also affect cloud formation. And how that all pans out and how those clouds change the balance of heat trapped versus heat reflected varies a lot across models. And for all these reasons, we like to give a range of what we call climate sensitivity, which is essentially, how sensitive is the climate to our emissions? And we usually define that as, if we double the amount of CO2 in the atmosphere — which is roughly what we're on track for by the end of the century today, we've already increased it by 50 percent — how much warming do we get at equilibrium? And that value is generally around three degrees C per doubling of CO2, but with a pretty wide range. In the most recent IPCC report, we said it could be anywhere from 2.5 degrees C at the low end of the likely range to about 4 degrees at the high end, 2 degrees to 5 degrees is the sort of very likely range that we gave in the most recent IPCC report.I recently watched an Apple TV+ miniseries called Extrapolations, and it looked at climate change and how it would affect us over the entire century. That was the number they really fixated on: 3 degrees Celsius. The environment they showed was pretty chaotic: lots of very, very bad heat waves, hurricanes, flooding. Civilization wasn't going to get wiped out or anything, but it seemed pretty nasty. So are we talking kind of really nasty climate effects from three degrees of warming Celsius?When we say 3 degrees, it sounds like a very small number, especially to us Americans are used to talking about things in Fahrenheit. But even when we think about the temperature from day to day, it might change, let's say 5.5 degrees Fahrenheit tomorrow, and that's noticeably warmer; 5.5 degrees Fahrenheit is the difference between 85 degrees and a bit above 90 degrees, but it doesn't sound huge. But the problem is, that's a global average number and no one lives in the global average. In fact, the global average is mostly the ocean. It turns out that where people do live, on land, is warming about 50 percent faster than the world as a whole. So if we talk about 3 degrees centigrade — or let's talk Fahrenheit for a moment, let's say 5.5 degrees Fahrenheit — over land, increase that by 50 percent, so let's say 8 degrees Fahrenheit globally over land where we all live. Even higher than that in high-latitude regions like the Arctic. We have bigger feedbacks associated with snow melting and exposing darker surfaces, so some regions are going to see really big changes.To put this number in perspective, the last ice age, which I think everyone would acknowledge was a very different planet than we have today, was only about 6 degrees centigrade colder than current temperatures globally. Obviously it was much colder in the northern latitudes, which were covered by ice sheets, but the tropics were not that much colder. And so it averages to about 6 degrees difference. So that would have impacts. Exactly what those impacts would be depends a lot on the systems we're talking about and the adaptive capacity of those systems. The natural world, I think in many ways, is going to be the worst hit by these changes. There are a lot of plant and animal species that live in fairly narrow ecological niches. And particularly in a world that's very fragmented by roads and human habitation, it's a lot harder for those plant and animal species to migrate to more temperate regions to be able to survive. So certainly there's a concern around large-scale extinction of many plant and animal species that can no longer live in the ecological niches that they've adapted to over the last tens of thousands of years and can't migrate quickly enough to adapt to that.In terms of impacts to human systems, there's a lot of different impacts from climate change and the degree to which those are catastrophic is going to depend a lot on how wealthy we are and how well we can adapt to it. If by the end of the century we're in a world that's similar to today, that has huge amounts of inequality with billions of people living at a dollar a day, I would worry a lot about the ability of people in those societies to adapt to more widespread extreme heat events, larger floods associated with more water vapor in the atmosphere, sea level rise, some of these other impacts. If we live in a world where we're all very wealthy and relatively equal on a country-by-country basis and within countries, then we have a much bigger ability to build sea walls, to have air conditioning inside, to genetically engineer crops to be more heat tolerance, the many other ways that humans can adapt to these changes. And so I think in many ways I see climate change less as an existential risk by itself and more as an existential risk multiplier. If we are in a world of weak institutions, of failing governments, of high inequality, I see climate as something that could help push societies over the edge. But I don't necessarily think at least a 3-degree world would be one that is the end of civilization by any stretch of the imagination, if we get our act together on these other issues.What is what you described as what is sort of the “business as usual” forecast, and then what is the, we really get serious about policy, and we can talk about what those policies are, that reduce carbon emissions?The good news is “business as usual” has already been changing a fair bit. Nowadays, it looks like business as usual is global emissions staying relatively flat. A decade ago, it seemed like doubling or tripling global emissions by the end of the century would not be out of the question. Certainly if you extrapolated the trends from previous decades, that's where we were headed. Nowadays, global coal use has largely plateaued and arguably is going to shrink in coming years. We have cheaper alternatives. Electric vehicles are taking off. There are many other technologies that are being developed and becoming increasingly cheap. And so it's harder to imagine a world where we're still burning massive amounts of coal, oil, and gas in 2100.We can reduce emissions, we can develop new technologies, and we can get them widely adopted. And if we do that and if we get emissions to zero by, say, 2070 or so globally, then we limit warming to below 2 degrees.Low-probability, high-risk scenariosDoes that make the very worst-case scenarios that maybe we were talking about a decade ago just highly unlikely?It certainly makes the worst-case emission outcomes highly unlikely. If we look at 3 degrees, for example, that could really end up anywhere between 2 degrees and above 4 degrees if we get unlucky because of the uncertainty in how the climate system responds to our emissions, because the Earth is such a complex system. Climate change is both planning for the central outcome but also trying to mitigate those risks. In some ways, we want to reduce emissions not just to get that mean down, but also as an insurance policy against the 5 or 10 percent more catastrophic potential outcomes there. I don't think we're necessarily completely out of the woods on a 4 C world by the end of the century if we roll sixes on all the proverbial climate dice, but I think we have made a lot of progress in making those outcomes less likely.Today we're headed toward, as I mentioned earlier, about 3 degrees of warming if emissions stay relatively constant, or a little bit below 3 degrees. But we can do much better than that. We can reduce emissions, we can develop new technologies, and we can get them widely adopted. And if we do that and if we get emissions to zero by, say, 2070 or so globally, then we limit warming to below 2 degrees. If we get emissions to zero by 2050, which is going to be a much harder lift given the amount of infrastructure in place today that relies on fossil fuels, then we could limit warming to maybe about 1.6 or 1.7 degrees. And if we build lots of machines to remove carbon from the atmosphere, plant lots of trees, do other things to actually get negative emissions, models suggest we could get temperatures down to 1.5 degrees, only 0.3 degrees above where we are today, by the end of the century.We are really on this acceleration of private sector and government spending on these technologies. But I think government does play a role here. I think most economists would acknowledge that what we're dealing with here is an externality. Reducing carbon emissionsWhen I look at what our responses might be, I tend to think, what will happen to emissions in a world where our responses will be constrained by our low collective tolerance for suffering and pain and deprivation and sacrifice? To me, that's a pretty important constraint. If there's one lesson I think we learned from the pandemic, it's people don't like shortages. We don't like to rough it in any way. In a world where, at least in the West, that's our attitude, how do we get emissions down in a somewhat timely manner?I think a lot of it relies both on the combination of human ingenuity and governments playing a role in catalyzing that ingenuity and allowing these technologies to scale. We've seen the biggest successes in mitigating climate change in technologies that slot in nicely to replace things that we enjoy today. We don't talk about it much, but Texas is the renewable energy capital of the US today, because it's cheaper to generate electricity with the wind and sun there than it is to burn coal and gas. Similarly, we've seen an explosion of electric vehicles in places like China and Europe, and the US is catching up, not necessarily because everyone there is a tree hugger, but because they're really fun to drive and they perform better and are lower cost in some cases than conventional vehicles. The more we can follow that model of developing new technologies that don't involve sacrifice, that don't involve necessarily giving up things we enjoy today, I think the more successful we're going to be.And that's led to a lot of money being spent on these things. In the last year, the globe spent about $1.1 trillion on mitigation technologies: renewable energy, electric vehicles, nuclear power, heat pumps, all that sort of stuff. That's up from $200 million a year or so a decade before or 15 years before. And so we are really on this acceleration of private sector and government spending on these technologies. But I think government does play a role here. I think most economists would acknowledge that what we're dealing with here is an externality. And by an externality, I mean it's something that has a social cost, but no one individually pays for it when they put carbon dioxide or other emissions in the atmosphere. So there has to be some role of internalizing that externality, either through (as economists would like to do) a price on carbon, or in a world where you can't do that for many reasons, subsidizing the good stuff to essentially account for the benefits it has of displacing fossil fuels, both in terms of their affecting climate change, but also conventional pollution. I think we discount a lot, particularly living in a place like the US, which has done a lot of work on this, how disastrous fossil fuels are for public health. There's somewhere in the range of a couple million people dying prematurely globally from pollution, particularly outdoor air pollution. And if you go to a place like India or China and walk around outside, it's pretty catastrophic some days in terms of the brown soup that is the air. We get a lot of co-benefits by cleaning up these conventional pollutants, particularly in places like Southeast Asia or South Asia, as well as reducing emissions of greenhouse gases.Reducing emissions, going to zero emissions, pulling emissions out of the air: Do these scenarios work with just renewable energy sources or is this a world that's using nuclear energy in some form far more than we currently are?So I think we necessarily need a variety of energy sources here, and there's been a lot of work done in recent years by the energy modeling community on this front. Renewables are great. Solar is super, super cheap; to be honest, a lot cheaper today than any of us thought it would be a couple decades ago. Wind is increasingly cheap. But they're also intermittent. The sun doesn't shine all the time; the wind doesn't blow all the time. Batteries are part of the solution to deal with that, but they're not a perfect solution. We tend to find that you get a much lower cost in scenarios where you also have a sizable chunk, maybe 20, 30, 40 percent, of your energy coming from what we call clean firm generation. Things like nuclear, like enhanced geothermal, potentially fossil fuels with carbon capture and storage, though those have some challenges in implementation, to support large amounts of renewable energy on the grid.You end up with a much more expensive system if you try to shoehorn in 100 percent renewables, and to be honest, it's pretty unnecessary. So I think we are going to see, and we're already starting to see, bigger investments in things like next-generation nuclear. I think we just need to figure out how to build them on time and on budget. The biggest problem with the nuclear industry in the US — certainly regulations have contributed to it — but I think it's just our inability to build these giant, bespoke megaprojects. Nuclear goes super over budget for the same reason the “Big Dig” in Boston does: You have this 10-year-long, many, many billion-dollar megaproject that has construction delays and all these other problems. The more we can learn from what renewables have gotten right, make things small, modular, pumped out in an assembly line, and less contingent on these giant construction projects, I think the better outcomes we'll see for things like nuclear.There's an economist, he passed fairly recently, Martin Weitzman from Harvard, and he wrote about the economics of climate change. And there's one quote that always sticks in my mind. He wrote that “Deep structural uncertainty about the unknown unknowns of what might go very wrong [with the climate] is coupled with essentially unlimited downside liability on possible planetary damages” and a “non-negligible” probability of a “collapse of planetary welfare.” He's talking about, you can't write off the possibility that we get some very bad outcomes. And I guess that's what worries me: If we're doing something to the atmosphere that we've never done before, what if the models are wrong and we get something really catastrophic, that really becomes a true existential risk? How much should I worry about that?I think we're all worried about unknown unknowns. For me, the odds of those happening, which are somewhat unknowable by definition, increase the more we push the Earth out of the climate we've seen for the past few million years. Right now we're around the range of what we saw in the Last Interglacial Period, about 120,000 years ago. If we get temperatures up to 3 degrees centigrade globally, we will be out of the range of anything we've seen for the last two million years or so, if not further back. And we know if we go further back into the Earth's history, there's some scary stuff back there. There are periods where we see very rapid increases of temperature associated with 90 percent extinction of all life on Earth, like the Paleocene/Eocene Thermal Maximum. And we don't have great explanations for all these things. A good example is, for warmer periods in the Earth's past, we think there's a mechanism where if temperatures get high enough, maybe 5 degrees above where they were in the pre-industrial period or a bit above 4 degrees above where we are today, suddenly all the stratocumulus cloud decks that cover much of the Earth's oceans disappear. And that leads to another 4 degrees warming on top of that. That sort of behavior seems to help explain some of these rapid warming events in the Earth's more distant past.Now, we think we're pretty far from experiencing something of that today. But maybe our models are wrong, or maybe the Earth is much more sensitive than we think. And again, rolling sort of sixes on the climate sensitivity and carbon cycle feedback dice leads us into those sorts of conditions. And so Marty Weitzman, who I did have the pleasure of knowing before he passed, had a great phrase to sum up that quote, which is that “when it comes to climate change, this thing is in the tail,” which is a very nerdy way to put it: The tails of these probability distribution functions, the low-probability but high-impact events, are really what should drive a lot of our concern around this and push us to reduce emissions more than we otherwise would if we were just planning for the most likely outcome.But whenever we talk about carbon dioxide removal, it is always important to emphasize that this stuff is expensive and it only makes sense to do at scale in a world where we're already cutting emissions dramatically. Carbon capture and carbon removalPeople will say, “What if the models are wrong?” and they assume they're only going to be wrong to the benefit of humanity. Maybe they're wrong to the detriment of humanity.We talked a little bit about reducing these emissions. You have carbon capture, where you pull it out of the air. How close is that technology to being something that can scale?When we talk about carbon capture, that's often a different thing than when we talk about carbon removal. Carbon capture generally means taking an existing fossil fuel plant…That could be trees too, right?Yeah, but carbon capture is mostly taking an existing fossil fuel plant like a coal, oil, and gas plant, sticking a unit on that captures the carbon coming out of it, and putting that underground. And there's a lot of funding for that in the new Inflation Reduction Act. The record on that over the last few decades has been a bit mixed. It's been hard for folks to make the economics work in practice. It's really complicated technically, but a lot of folks are confident that we can get there with some of those technologies. If a coal plant with carbon capture is going to be cheaper than a nuclear plant or renewable plant is a separate question. And I'm a lot more skeptical on the economics of carbon capture there.Now, carbon dioxide removal is a slightly different thing. And there we're talking about technologies that don't stop emissions from coming out of a smokestack, but instead take carbon that's already in the atmosphere and pull it back out. And most of our models suggest that we are going to need a lot of that down the road, in part because we can't fully get rid of all of the emissions from all of the parts of our economy. And the real challenge with climate change, or what I like to call the “brutal math” of climate change is that as long as our emissions remain above zero, the Earth continues to warm. CO2 remains in the atmosphere for an extremely long period of time; it takes about 400,000 years to fully clear out a ton of fossil CO2 we emit today through natural processes. So we end up needing a lot of carbon removal to both balance out what we call residual emissions and potentially to deal with overshoot. If we figure out that we really don't want temperatures to go above 1.5 degrees, but they're headed toward 1.7, we're going to have to pull a bunch of carbon out of the atmosphere to bring temperatures back down. It's only a small part of the solution. Maybe 10 percent of the solution to climate change writ large is carbon dioxide removal. But for a problem as big as climate change, 10 percent still matters a lot since solar is probably 20 percent, electric vehicles are probably 20 percent, heat pumps might be 10 percent. And there's a lot of technologies people are developing to do that. Direct air capture is the one that gets a lot of press: the sort of big fans that suck carbon out of the air, though they're incredibly energy intensive. But there are a lot of ways that leverage natural processes as well. Planting trees is a good one, though it has a lot of challenges in keeping the carbon in those trees in a warming world, particularly as we see more wildfires, more pine bark beetle outbreaks that used to die in cold winter temperatures and don't anymore. And so it's hard to justify planting trees as a way of permanently taking carbon out of the atmosphere, but it's still quite valuable. There's also a lot of interesting work being done around using biomass to sequester carbon, so taking residues from commercial timber operations, burning them, and putting their carbon content underground. Something called BECCS, or bioenergy with carbon capture and storage, that a lot of people are excited about.Then there are other interesting ways to leverage the natural carbon cycle. For example, over long periods, the weathering of certain types of rocks like basalt or olivine drives a lot of atmospheric CO2 absorption over the course of millions of years. And so a lot of scientists are trying to figure out ways to speed that up. If you take rock dust and spread it on farm fields, it can help manage the pH of soils, it can add some nutrients. And it turns out that as that basalt dust weathers, it absorbs carbon to the atmosphere, it turns it into stable bicarbonate and then flows out to the ocean and eventually forms limestone on the bottom of the ocean. Stuff like that, or adding alkalinity directly to the ocean to counteract ocean acidification, can also lead to more CO2 uptake from the air, because the amount of carbon dioxide the ocean absorbs in the atmosphere depends on how acidic the surface level of the layers of the water are. Scientists are working on tons of different technologies here. And actually my day job these days with Stripe and Frontier is helping support companies to do that. So there's lots of exciting stuff there. But whenever we talk about carbon dioxide removal, it is always important to emphasize that this stuff is expensive and it only makes sense to do at scale in a world where we're already cutting emissions dramatically. If you keep burning fossil fuels willy-nilly and spend a ton of money on a bit of carbon dioxide removal, it's not going to make any difference.Why are you interested in this subject?I think it's an underexplored area. Certainly until the last few years, no one was really putting any money or resources into it at scale. And it's something that is going to have to be an important part of the solution in the next few decades, and so I think this is the decade that we should be spending resources to figure out what works and what can scale for decades to come. We probably should spend about 1 percent of the money we spend on reducing emissions, but historically we've been spending a lot less than that.And why are you also more broadly interested in the entire topic of climate change rather than, I don't know, tax policy or something?I come to it from a scientific background. I just find the Earth's climate fascinating. It's super complex. It's hard to fully understand. We've really made leaps and bounds in progress over the last few decades, but there's so much we still don't know. And so it's just a fascinating area from a scientific standpoint, but it's also one where the importance to the society is quite large. I try not to wade too much into the policy solutions to it, but certainly helping understand the likely impacts of our actions affects a lot of choices that policymakers and others make. There's no one right answer. To your question earlier, people debate renewables versus nuclear and all these other things. Knowing what the impacts of climate change are, what the risks are, and how we can actually get to certain outcomes based on our decisions, I feel like is really important to set the stage for people to use the science in the real world. And it's exciting to work in an area of science where there is a practical, real-world application of it. And not just studying one plant species that lives on top of one mountain in a remote part of the world. We're looking at these big questions that affect everyone over the next century. This is a public episode. If you'd like to discuss this with other subscribers or get access to bonus episodes, visit fasterplease.substack.com/subscribe

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2023.07.22.550177v1?rss=1 Authors: Knapp, B., Willis, L., Gonzalez, C., Vashistha, H., Touma, J. J., Tikhonov, M., Ram, J., Salman, H., Elias, J. E., Huang, K. C. Abstract: The impact of temperature on growth is typically considered under heat- or cold-shock conditions that elicit specific regulation. In between, cellular growth rate varies according to the Arrhenius law of thermodynamics. Here, we use growth-rate dynamics during transitions between temperatures to discover how this behavior arises and what determines the temperature sensitivity of growth. Using a device that enables single-cell tracking across a wide range of temperatures, we show that bacteria exhibit a highly conserved, slow response to temperatures upshifts with a time scale of ~1.5 doublings at the higher temperature, regardless of initial/final temperature or nutrient source. We rule out transcriptional, translational, and membrane reconfiguration as potential mechanisms. Instead, we demonstrate that an autocatalytic enzyme network incorporating temperature-sensitive Michaelis-Menten kinetics recapitulates all temperature-shift dynamics, reveals that import dictates steady-state Arrhenius growth behavior, and successfully predicts alterations in the upshift response observed under simple-sugar or low-nutrient conditions or in fungi. These findings indicate that metabolome rearrangement dictates how temperature affects microbial growth. Copy rights belong to original authors. Visit the link for more info Podcast created by Paper Player, LLC

I dagens avsnitt av Techrekpodden har vi nöjet att välkomna Peter Arrhenius, VD på Inera. Inera ligger bakom flera digitala tjänster som spelar en viktig roll i digitaliseringen av offentlig sektor och sjukvården, inklusive 1177. Peter delar med sig av lärdomar från sin tidigare karriär och berättar hur han fick sitt första ledarjobb för att till slut landa som vd på Inera. Huvudfokus i dagens avsnitt ligger på digitaliseringen av offentlig sektor. Var har vi halkat efter och vad behöver vi fokusera på framåt? Peter delar även med sig av sina tankar kring rekrytering av en ny CIO till Inera, samt vilka utmaningar och möjligheter det innebär. Avslutningsvis får vi några trendspaningar och hur dessa insikter påverkar Ineras strategi och framtida satsningar. Är ditt företag i behov av IT-rekrytering, eller vill du tipsa om en gäst? Hör av dig till cj@ants.se eller läs mer om hur vi arbetar på ants.se   Prenumerera på vårt nyhetsbrev. 

1911 - Marie era discreta, pero tenía un valor envidiable y una determinación imbatible. Empuñando uno y otra, le contesta a Arrhenius y, esperaba, a través de él, a toda la academia, toda Suecia y todos los que perdían su tiempo pendientes de ella. En la voz, Bárbara Espejo.

Natürlich wurden die Grenzen des Wachstums prominent mit der gleichnamigen Publikation des Club of Rome 1972 ins öffentliche Bewusstsein gebracht. Seit der Zeit ringen wir mir den Konsequenzen dieser Erkenntnisse – mal weniger, zum Glück aktuell endlich auch mal mehr. Das begrenzte Vorkommen von Ressourcen war schon viel länger bekannt. Der 1859 geborene schwedische Nobelpreisträger für Chemie Svante Arrhenius machte auf die Schwindenden Mengen von Erdöl, Kohle und Metallen aufmerksam. Das Berliner Tageblatt druckte am 1. Oktober 1922 einen diesbezüglich aussagekräftigen Abschnitt des Buches „Die Chemie und das moderne Leben“ von ihm ab. Arrhenius zählt darüber hinaus zu den ersten Wissenschaftlern, die eine Verbindung von Erderwärmung und menschengemachten Kohlendioxid-Emissionen postulierten – da erscheint es schon beinahe zwingend, dass Arrhenius Mutter tatsächlich eine geborene Thunberg war. Paula Leu schaut mit uns auf die Zukunft der Energievorräte.

Josiah Gibbs revolutionized physical chemistry with his mathematics of thermodynamics and chemical equilibria, but published in an obscure journal few read. Wilhelm Ostward explained catalysis with his idea of an intermediate. Einstein figured out the cause of Brownian motion, and gave sufficient proof of atoms and molecules that all scientists accepted atomic theory. These developments led to the journal Zeitschrift für Physikalische Chemie, which still exists today. Arrhenius's ionic dissociation explained many of water's properties, and led eventually to Søren Sørensen's pH designation of acids and bases. Guest, Vincent Falcone, Head Brewer of City-State Brewing in Washington, DC, discusses pH and beer.Support the show

Van Rossum discusses the Arrhenius equation, proposing that it applies to economic behavior; discusses the issue of mulcting in markets; and provides a brief history of the Walloons.

 In this episode we discuss the efforts of three scientists–Svante Arrhenius, Guy Callendar, and Charles David Keeling–to figure out exactly what fossil fuel emissions might be doing to the atmosphere and the global temperature. Surprisingly, Arrhenius and other early climate scientists didn't necessarily think that global warming would be…such a bad thing? But by the 1970s scientists began to push for more concerted efforts to research the effects of increasing carbon dioxide concentrations in the atmosphere. We'll pick up that part of the story in the next episode. You'll also hear about Guy Callendar's contributions to climate science. Guy was a fellow who held no academic degrees in science but did live through a dangerous childhood. We'll conclude with Charles Keeling and his famous curve showing how the CO2 concentration in the atmosphere began increasing at an accelerating rate during the twentieth century.  

Welcome to The Nonlinear Library, where we use Text-to-Speech software to convert the best writing from the Rationalist and EA communities into audio. This is: Person-affecting views can often be Dutch booked, published by Rohin Shah on July 7, 2022 on The Effective Altruism Forum. This is a short reference post for an argument I wish was better known. A common intuition people have is that our goal is "Making People Happy, not Making Happy People". That is: Making people happy: if some person Alice will definitely exist, then it is good to improve her welfare Not making happy people: it is neutral to go from "Alice won't exist" to "Alice will exist". Intuitively, if Alice doesn't exist, she can't care that she doesn't live a happy life, and so no harm was done. This position is vulnerable to a Dutch book, that is, there is a set of trades that it would make that would achieve nothing and lose money with certainty. Consider the following worlds: World 1: Alice won't exist in the future. World 2: Alice will exist in the future, and will be slightly happy. World 3: Alice will exist in the future, and will be very happy. (The worlds are the same in every other aspect. It's a thought experiment.) Then this view would be happy to make the following trades: Receive $0.01 to move from World 1 to World 2 ("Not making happy people") Pay $1.00 to move from World 2 to World 3 ("Making people happy") Receive $0.01 to move from World 3 to World 1 ("Not making happy people") The net result is to lose $0.98 to move from World 1 to World 1. FAQ Q. Why should I care if my preferences lead to Dutch booking? This is a longstanding debate that I'm not going to get into here. I'd recommend Holden's series on this general topic, starting with Future-proof ethics. Q. In the real world we'd never have such clean options to choose from. Why does this matter? See previous answer. Q. In step 2, Alice was definitely going to exist, which is why we paid $1. But then in step 3 Alice was no longer definitely going to exist. If we knew step 3 was going to happen, then we wouldn't think Alice was definitely going to exist, and so we wouldn't pay $1. If your person-affecting view requires people to definitely exist, taking into account all decision-making, then it is almost certainly going to include only currently existing people. This does avoid the Dutch book but has problems of its own, most notably time inconsistency. For example, perhaps right before a baby is born, it take actions that as a side effect will harm the baby; right after the baby is born, it immediately undoes those actions to prevent the side effects. Q. What if we instead have ? Often these variants are also vulnerable to the same issue. For example, if you have a "moderate view" where making happy people is not worthless but is discounted by a factor of (say) 10, the same example works with slightly different numbers: Let's say that "Alice is very happy" has an undiscounted worth of 2 utilons. Then you would be happy to (1) move from World 1 to World 2 for free, (2) pay 1 utilon to move from World 2 to World 3, and (3) receive 0.5 utilons to move from World 3 to World 1. More generally, Arrhenius proves an impossibility result that applies to all possible population ethics (not just person-affecting views), so (if you want consistency) you need to bite at least one of those bullets. Further resources On the Overwhelming Importance of Shaping the Far Future (Nick Beckstead's thesis) An Impossibility Theorem for Welfarist Axiologies (Arrhenius paradox, summarized in Section 2 of Impossibility and Uncertainty Theorems in AI Value Alignment) For this post I'll assume that Alice's life is net positive, since "asymmetric" views say that if Alice would have a net negative life, then it would be actively bad (rather than neutral) to move Alice from "won't exist" to "will exist". By giving it $0.01, I'm making it so that it strictly prefers to take the trade (rather than being indifferent to t...

I dagens avsnitt pratar vi med Peter Arrhenius och Fredrik Agetoft, manusförfattarna till tittarsuccén Clark - en dramatisering av den omtalade Clark Olofssons liv. Både Peter och Fredrik har en lång lista av manuscredits bakom sig, bland annat som författare på Beck. Vi snackar bransch, hur skapandeprocessen för Clark såg ut, samt om samarbetet med Netflix och Jonas Åkerlund, som är regissör och även manusförfattare till den explosiva serien. Host: Emma Hedman och Sonja Strandberg Producerat av: Story Academy

In Episode 3 of the Periodic Fable, Hallam goes into detail about his journey to becoming a Chemist, the route he took, the life lessons he's learnt on the way, and the work he's spent the last 10 years doing in the vital field of polymers and plastic production  Cameron then takes us on another True Periodic Fable, diving into the world of Arrhenius before Hallam  looks at what's in the news in the world of science and chemistry.  

A huge hello to both our guests this week, Ingela P Arrhenius and Camilla Reid! Ingela and Camilla are the award-winning team behind the bestselling, Felt Flaps Where's Mr? series. This week we're talking all things pre-school and connecting books with very young readers. With new title, Peekaboo House out June 3rd 2021, we're excited to share this episode with you. For more information on the latest release and to read more about their publications with Nosy Crow, visit this link: https://nosycrow.com/product/peekaboo-house/ For more information or to get in contact, follow The Bookseller on Twitter @thebookseller and Rocket on Twitter or Instagram @WeAreRocketHQ!https://twitter.com/thebookseller https://twitter.com/WeAreRocketHQ https://www.instagram.com/wearerockethq/ Produced by youth marketing business Rocket: www.wearerocket.co.ukHosted by Charlotte Eyre, Children's Editor at The Bookseller: https://twitter.com/CharlotteLEyrehttps://www.thebookseller.com Our GDPR privacy policy was updated on August 8, 2022. Visit acast.com/privacy for more information.

With the launch of our third journal,  JCPP Advances, we're bringing you a series of podcast that focus on the papers and editors featured in the publication. In this podcast we speak to Dr. Bianca Arrhenius, medical doctor from Helsinki, Finland, and PhD student at the University of Turku, who is lead author on the paper 'Relative Age and Specific Learning Disorder Diagnosis'. Bianca summarises the paper and methodology, the implications of the findings for professionals working in education and in child mental health, and highlights that knowledge of the topic is crucial for educational policymaking. Bianca also discusses whether immature children should start school later than their relatively older peers, whether the school age be should be raised, and the implications of your findings for children and their families.

From the BEL archieves, * Real Science Radio has a Far Ranging Conversation with Krauss: Co-hosts Bob Enyart and Fred Williams present Bob's interview of theoretical physicist (emphasis on the theoretical), atheist Lawrence Krauss. Fred says, "It's David vs. Goliath, but without the slingshot." As the discussion ranges from astronomy and anatomy to cosmology and physics, most folks would presume that Dr. Krauss would take apart Enyart's arguments, especially when the Bible believer got the wrong value for the electron-to-proton mass ratio. But the conversation reveals fascinating dynamics from the creation/evolution debate. (The planned 25-minute interview ran 40 minutes, so there's also a Krauss Part II and once in each half we say, "Stop the tape, stop the tape," to comment.) * "All Evidence Overwhelmingly Supports the Big Bang": Contradicting Dr. Krauss'

From the BEL archieves, * Real Science Radio has a Far Ranging Conversation with Krauss: Co-hosts Bob Enyart and Fred Williams present Bob's interview of theoretical physicist (emphasis on the theoretical), atheist Lawrence Krauss. Fred says, "It's David vs. Goliath, but without the slingshot." As the discussion ranges from astronomy and anatomy to cosmology and physics, most folks would presume that Dr. Krauss would take apart Enyart's arguments, especially when the Bible believer got the wrong value for the electron-to-proton mass ratio. But the conversation reveals fascinating dynamics from the creation/evolution debate. (The planned 25-minute interview ran 40 minutes, so there's also a Krauss Part II and once in each half we say, "Stop the tape, stop the tape," to comment.) * "All Evidence Overwhelmingly Supports the Big Bang": Contradicting Dr. Krauss'

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.09.11.293670v1?rss=1 Authors: Plaskon, D., Henderson, K., Felth, L., Molzahn, C., Evensen, C., Dyke, S., Shkel, I., Record, T. Abstract: In transcription initiation, specific contacts between RNA polymerase (RNAP) and promoter DNA are disrupted as the RNA-DNA hybrid advances into the cleft, resulting in escape of RNAP. From the pattern of large and small rate constants for steps of initiation at {lambda}PR promoter at 19{degrees}C, we proposed that in-cleft interactions are disrupted in extending 3-mer to 5-mer RNA, -10 interactions are disrupted in extending 6-mer to 9-mer, and -35 interactions are disrupted in extending 10-mer to 11-mer, allowing RNAP to escape. Here we test this mechanism and determine enthalpic and entropic activation barriers of all steps from kinetic measurements at 25{degrees}C and 37{degrees}C. Initiation at 37{degrees}C differs significantly from expectations based on lower-temperature results. At low concentration of the second iNTP (UTP), synthesis of full-length RNA at 37{degrees}C is slower than at 25{degrees}C and no transient short RNA intermediates are observed, indicating a UTP-dependent bottleneck step early in the 37{degrees}C mechanism. Analysis reveals that the 37{degrees}C {lambda}PR OC (RPO) cannot initiate and must change conformation to a less-stable initiation complex (IC) capable of binding the iNTP. We find that IC is the primary {lambda}PR OC species below 25{degrees}C, and therefore conclude that IC must be the I3 intermediate in RPO formation. Surprisingly, Arrhenius activation energy barriers to five steps where RNAP-promoter in-cleft and -10 contacts are disrupted are much smaller than for other steps, including a negative barrier for the last of these steps. We interpret these striking effects as enthalpically-favorable, entropically-unfavorable, stepwise bubble collapse accompanying disruption of RNAP contacts. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.08.27.270488v1?rss=1 Authors: Sadhukhan, S., Nandi, S. K. Abstract: Glassy dynamics in a confluent monolayer is indispensable in morphogenesis, wound healing, bronchial asthma, and many others; a detailed theoretical understanding for such a system is, therefore, important. We combine numerical simulations of a cellular Potts model and an analytical study based on random first order transition (RFOT) theory of glass, develop a comprehensive theoretical framework for a confluent glassy system, and show that glassiness is controlled by the underlying disordered energy landscape. Our study elucidates the crucial role of geometric constraints in bringing about two distinct regimes in the dynamics, as the target perimeter P_0 is varied. The extended RFOT theory provides a number of testable predictions that we verify in our simulations. The unusual sub-Arrhenius relaxation results from the distinctive interaction potential arising from the perimeter constraint in a regime controlled by geometric restriction. Fragility of the system decreases with increasing P_0 in the low-P_0 regime, whereas the dynamics is independent of P_0 in the other regime. The mechanism, controlling glassiness in a confluent system, is different in our study in comparison with vertex model simulations, and can be tested in experiments. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.08.21.260885v1?rss=1 Authors: Bunzel, H. A., Anderson, R., Hilvert, D., Arcus, V. L., van der Kamp, M. W., Mulholland, A. J. Abstract: Activation heat capacity is emerging as a crucial factor in enzyme thermoadaptation, as shown by non-Arrhenius behaviour of many natural enzymes. However, its physical origin and relationship to evolution of catalytic activity remain uncertain. Here, we show that directed evolution of a computationally designed Kemp eliminase introduces dynamical changes that give rise to an activation heat capacity absent in the original design. Extensive molecular dynamics simulations show that evolution results in the closure of solvent exposed loops and better packing of the active site with transition state stabilising residues. Remarkably, these changes give rise to a correlated dynamical network involving the transition state and large parts of the protein. This network tightens the transition state ensemble, which induces an activation heat capacity and thereby nonlinearity in the temperature dependence. Our results have implications for understanding enzyme evolution (e.g. in explaining the role of distal mutations and evolutionary tuning of dynamical responses) and suggest that integrating dynamics with design and evolution will accelerate the development of efficient novel enzymes. Copy rights belong to original authors. Visit the link for more info

Nyhetssändning från kulturredaktionen P1, med reportage, nyheter och recensioner.

SOR 518 The Folly of Reliability Predictions Abstract Kirk discusses the continued reliance on the misleading approach of using reliability prediction for reliability development. Key Points Join Kirk as he discusses MIL Handbook 217 and its prodigy, the Arrhenius equation, and the reality of early electronics components (tubes, discrete transistors) being a major factor overall […] The post SOR 518 The Folly of Reliability Predictions appeared first on Accendo Reliability.

Redan i slutet av 1800-talet förstod Svante Arrhenius att människan värmer upp jordklotet. Under ett år räknade han för hand och skapade världens första klimatmodell. Första delen av Klimatinsikten tar dig 200 år bakåt i tiden. Det var då forskare förstod att något i atmosfären håller kvar värme. Det som vi idag kallar växthuseffekten. Den svenske forskaren Svante Arrhenius var sedan först med att foga ihop kunskapen om klimatet till en teori, som står sig än idag. Men han var inte det minsta bekymrad över uppvärmningen tvärt om välkomnade han den. I programmet medverkar Henning Rodhe, professor vid meteorologiska institutionen vid Stockholms universitet, och Sverker Sörlin, idéhistoriker och professor i miljöhistoria vid Kungliga tekniska högskolan. Programledare Malin Avenius Producent Peter Normark peter.normark@sverigesradio.se Ljudtekniker Olof Sjöström

Mitt under Nobelveckan måste vi ju släppa ett specialavsnitt om Nobelpriset, men från ett annat perspektiv än festligheterna, glittret och äran. Vi vill ta reda på vad Nobelpristagaren Svante Arrhenius privatliv under förra seklet kan säga om naturvetenskapernas och Nobelprisets fortsatta manliga dominans idag, och träffar Staffan Bergwik, docent i idé- och lärdomshistoria vid Stockholms universitet. Han har bland annat forskat om genusstrukturer inom naturvetenskapen under första halvan av 1900-talet, och berättar om hur Arrhenius privatliv, med en borgerlig hemmafru och barn, var tätt sammanflätat med det offentliga livet som en av tidens mäktigaste vetenskapsmän. Vad säger dåtidens normer och strukturer om vetenskapen och Nobelpriset idag?

This podcast covers chemical kinetics and solubility. First, I cover topics within kinetics including: general concept, collision theory, rate laws, and the Arrhenius equation. Then, I break down solubility. Topics in this segment include general concept, solubility product (Ksp), the common ion effect, selective precipitation, and Henry’s law. Please email me if you have any comments or concerns: MCATpodcast@medschoolcoach.com Thanks for listening!

Acesse @academiafernandinhobeltrao no instagram e saiba tudo o que tá rolando na escola.

Learn about how researchers discovered that your lungs actually make blood; how you can tell the temperature from cricket chirps; and a strategy for maximizing your focus and achieving your goals that comes from billionaire business magnate Warren Buffett. In this podcast, Cody Gough and Ashley Hamer discuss the following stories from Curiosity.com to help you get smarter and learn something new in just a few minutes: Lungs Actually Make Blood — https://curiosity.im/2Gr6lB4 You Can Tell The Temperature From Cricket Chirps, Thanks To Dolbear's Law — https://curiosity.im/2GgNIjj To Maximize Your Focus and Achieve Your Goals, Try Warren Buffett's 2-List Strategy — https://curiosity.im/2GgO3T7 If you love our show and you're interested in hearing full-length interviews, then please consider supporting us on Patreon. You'll get exclusive episodes and access to our archives as soon as you become a Patron! https://www.patreon.com/curiositydotcom Download the FREE 5-star Curiosity app for Android and iOS at https://curiosity.im/podcast-app. And Amazon smart speaker users: you can listen to our podcast as part of your Amazon Alexa Flash Briefing — just click “enable” here: https://curiosity.im/podcast-flash-briefing.

Konstfolket rodnar av respekt för den mäktiga och coola chefen för Bonniers konsthall. Intresset för konstnärliga metoder, det okända som drivkraft för inlärning och kärleken till publiken är vägledande både historiskt och för framtiden när konsthallen nu öppnar igen efter renovering. Hör Sara Arrhenius! Producerat av Eric Palmcrantz, Figaro Music & Media Group

Dissociazione gassosa. Equilibri eterogenei. Acidi e basi, forti e deboli, teorie di Arrhenius, Lowry-Bronsted, Lewis. Autoionizzazione e prodotto ionico dell'acqua.

In this episode, developments in electrochemistry by Berzelius, Faraday, Arrhenius, Oswald, van't Hoft and Werner are discussed.

Gustaf Arrhenius är professor i praktisk filosofi vid Stockholms universitet och chercheur associé vid Collège d’études mondiales. Arrhenius forskningsområden ligger framför allt inom moralisk och politisk filosofi och han är speciellt intresserad i frågor som rör skärningspunkten mellan moralisk och politisk filosofi och medicinsk och samhällsvetenskaplig forskning (t.ex. ekonomi, juridik och statsvetenskap). Han är den svenska koordinatorn för det Fransk-svenska ... Read More

AFM-based dynamic single-molecule force spectroscopy was used to stretch carboxymethylated amylose (CMA) polymers, which have been covalently tethered between a silanized glass substrate and a silanized AFM tip via acid-catalyzed ester condensation at pH 2.0. Rupture forces were measured as a function of temperature and force loading rate in the force-ramp mode. The data exhibit significant statistical scattering, which is fitted with a maximum likelihood estimation (MLE) algorithm. Bond rupture is described with a Morse potential based Arrhenius kinetics model. The fit yields a bond dissociation energy De = 35 kJ mol−1 and an Arrhenius pre-factor A = 6.6 × 104 s−1. The bond dissociation energy is consistent with previous experiments under identical conditions, where the force-clamp mode was employed. However, the bi-exponential decay kinetics, which the force-clamp results unambiguously revealed, are not evident in the force-ramp data. While it is possible to fit the force-ramp data with a bi-exponential model, the fit parameters differ from the force-clamp experiments. Overall, single-molecule force spectroscopy in the force-ramp mode yields data whose information content is more limited than force-clamp data. It may, however, still be necessary and advantageous to perform force-ramp experiments. The number of successful events is often higher in the force-ramp mode, and competing reaction pathways may make force-clamp experiments impossible.

This short video describes the empirically derived Arrhenius Law.

The following video looks at the Arrhenius and Bronsted-Lowry Theories of Acids and Bases. We look at how acids and bases dissociate in solutions.

The sun radiates energy toward the earth, and the earth radiates much of that energy back. But some of it is blocked by carbon dioxide (CO2). The Swedish scientist Svante Arrhenius theorized changing amounts of CO2 could therefore change the earth’s surface temperature. Now, the equator is warm and the poles are cold, and we can demonstrate why this is by using a heat-sensitive ball and a hot light bulb. This is a major piece of the climate puzzle which we’ll connect in the coming segments.

What scientific and natural records reveal about global climate over the last 150 years.

Transcript -- What scientific and natural records reveal about global climate over the last 150 years.

What scientific and natural records reveal about global climate over the last 150 years.

Transcript -- What scientific and natural records reveal about global climate over the last 150 years.

Die Anwendung der Einzelmolekülspektroskopie auf poröse Festkörper wird erstmals in dieser Arbeit beschrieben. Um diese relativ neue Methode auf die Untersuchung von Farbstoffen in porösen Festkörpern anzuwenden, wurde ein konfokales Mikroskop so umgebaut, daß es zur Detektion und Spektroskopie einzelner Moleküle einsatzfähig ist. Dafür wurden verschiedene optische Detektionssysteme aufgebaut, um alle im Fluoreszenzlicht enthaltenen Informationen zu erhalten. Mit einer Avalanche Photodiode wurde die Empfindlichkeit des Mikroskops auf die Detektion einzelner Lichtquanten gesteigert. Mit einem gepulsten Laser wurde der ZeitbereichObwohl die Einzelmolekülspektroskopie im Vordergrund der Arbeit steht, sind auch einige interessante Beobachtungen an porösen Materialien mit vielen Farbstoffmolekülen (Ensemblemessungen) durchgeführt worden. Aufgrund des hohen dreidimensionalen Auflösungsvermögen des konfokalen Mikroskopes war es möglich, auch an nur wenige Mikrometer großen Kristallen ortsaufgelöste Untersuchungen durchzuführen. Bisher war es oft nicht möglich, zwischen Oberflächeneffekten und Eigenschaften, die in der Porenstruktur hervorgerufen werden, zu unterscheiden. Untersuchungen mit vielen Farbstoffmolekülen (Ensemblemessungen) zeigten, daß auch scheinbar perfekte Kristalle im Inneren oft unregelmäßig aufgebaut sind. So wurde eine Methode entwickelt, um Defektstrukturen in Kristallen mit Fluoreszenzfarbstoff anzufärben und dreidimensional mit dem konfokalen Mikroskop darzustellen. Große kalzinierte MFI Kristalle besitzen Defektstrukturen, die sich im Inneren entlang der langen Kristallachse ausbreiten. Darüber hinaus konnte gezeigt werden, daß scheinbar homogen mit Farbstoff beladene Kristalle oft eine sehr ungleichmäßige Farbstoffverteilung besitzen. Auch Kristalle, die schon während der Synthese mit Farbstoff beladen werden, sind oft nicht gleichmäßig beladen. Dreidimensionale Fluoreszenzbilder von großen und regelmäßig aufgebauten AlPO4-5 Kristallen, die mit dem Farbstoff DCM beladen wurden, zeigten verschiedene geordnete und ungeordnete Strukturen. Durch die Analyse der Polarisation kann die Orientierung der Farbstoffmoleküle untersucht werden. Untersuchungen an verschieden großen Oxazin Farbstoffen, die während der Synthese in AlPO4-5 eingebaut wurden, zeigten, daß die Ausrichtung entlang der Porenrichtung mit steigender Molekülgröße abnimmt. Das kleine Oxazin 1 ist noch relativ gut orientiert, während das große Oxazin 750 ohne Vorzugsrichtung eingebaut wird. In verschiedenen M41S Materialien wurde die Diffusion von Farbstoff untersucht. Fluoreszenzbilder von M41S Monolithen zeigten das Eindiffundieren verschiedener Farbstoffe in den Festkörper. Über die zeitabhängige Analyse der Eindringtiefe konnten dadurch die Diffusionskonstanten ermittelt werden. Es zeigte sich, daß die Diffusion jeweils bei geladenen Molekülen, größeren Molekülen und bei kalziniertem Monolithen verlangsamt wird. Die Untersuchung des Diffusionsverhaltens in einer M41S Nadel zeigte eine etwa doppelt so schnelle Diffusion quer zur Nadel. Dies steht in Übereinstimmung zu elektronenmikroskopischen Bildern, die zeigen, daß die Nadeln aus zirkularen Poren besteht, die quer zur Nadelrichtung orientiert sind. Im Verlauf dieser Arbeit wurden erstmals einzelne Farbstoffmoleküle innerhalb von porösen Festkörpern detektiert. Im Vergleich zu Referenzproben, bei denen der Farbstoff in einer dünnen Polymerschicht eingebettet wird, ist das Signal zu Untergrund Verhältnis der Einzelmoleküluntersuchungen in den porösen Festkörpern etwas geringer. Auch an der Photostabilität der Fluoreszenzfarbstoffe konnte durch die Einlagerung in die Porenstrukturen keine Verbesserung beobachtet werden. Die Moleküle können nicht nur detektiert, sondern auch spektroskopiert werden. Dabei konnten durch die Analyse der Fluoreszenz verschiedene Parameter bestimmt werden, wie folgende Tabelle zeigt: der Detektion bis hinab in den Nanosekundenbereich erweitert. Durch den Einbau einer Lambda-Halbe Platte wurde die Polarisation des Laserlichtes beeinflußt, um die Orientierung eines einzelnen Moleküls zu bestimmen. Schließlich wurde durch den Einsatz eines Prismas und einer empfindlichen CCD-Kamera die spektrale Aufspaltung ermöglicht, um damit die Fluoreszenzspektren zu bestimmen. Mit allen Experimenten war es nicht nur möglich statische Eigenschaften der einzelnen Fluoreszenzfarbstoffe zu bestimmen, sondern auch deren dynamische Veränderungen. Eine der wichtigsten Anforderungen an organische Farbstoffmoleküle für Einzelmolekülspektroskopie ist die Photostabilität. Um geeignete Farbstoff für den Einbau in die Porenstrukturen zu erhalten, wurden die Photostabilitäten verschiedener Farbstoffe untersucht. Dazu wurden von einigen ausgewählten Farbstoffen die detektierbaren Fluoreszenzphotonen gezählt. Es stellte sich heraus, daß das Farbstoffmolekül TDI in einer dünnern PMMA Schicht eine außergewöhnlich hohe Photostabilität besitzt. Einige TDI-Molekülen emittieren sogar 10 11 Fluoreszenzphotonen bis zum irreversiblen Photobleichen. Zum anderen wurde für sehr instabile Farbstoffmoleküle eine Methode entwickelt, um durch Bleichexperimente an einem Ensemble von Molekülen mit dem konfokalen Mikroskop die Anzahl der emittierten Fluoreszenzphotonen zu ermitteln. Für den Einbau in poröse Festkörper wurden daraufhin einige Oxazinfarbstoffe und das in biologischen Untersuchungen häufig verwendete Cy5 ausgewählt. Diese Farbstoffe können im roten Spektralbereich anreget werden und besitzen mit etwa 10 7 emittierten Fluoreszenzphotonen eine relativ gute Photostabilität. Als Porenstruktur wurden besonders zwei Materialien untersucht. Die Porenstruktur AFI, die im Material AlPO4-5 vorkommt, besitzt eindimensionale Kanäle, die hexagonal wie in einer Bienenwabe angeordnet sind. Von diesem Material können auch regelmäßige Kristalle hergestellt werden, die bis zu einem Millimeter lang sind. Leider sind die Poren des AlPO4-5 mit 0,73 nm Innendurchmesser sehr eng. Alle geeigneten Fluoreszenzfarbstoffe sind etwas größer und werden daher in mehr oder weniger großen Deformationen in dem Kristall eingelagert. Größere Poren besitzen die mesoporösen M41S Materialien. In diese passen alle Farbstoffe ohne Deformation hinein. Jedoch ist die Kristallgröße der M41S Materialien auf wenige µm beschränkt. Mit der Methode der homogenen Fällung können die bisher größten hexagonal geordneten MCM-41 Kristalle hergestellt werden. Zentimeter große hexagonale M41S Festkörper (Monolithe), die durch eine Synthese mit einem Flüssigkristall hergestellt werden, verlieren, wie hier gezeigt wird, während der Synthese ihre eindimensionale Ausrichtung der Poren.Beobachtete Eigenschaft des Lichtes Information aus statischen Bestimmungen Information aus zeitabhängigen Bestimmungen Intensität immer Notwendig Raten (Singulett, Triplett, etc.) Ort Position Diffusion, Transport Polarisation Orientierung Drehung, Rotation Energie Fluoreszenzspektren spektrale Diffusion Diese verschiedenen Untersuchungsmöglichkeiten wurden aufgebaut und an einer Referenzprobe (TDI in PMMA) getestet. Für die Datenanalyse konnte zum Teil auf Methoden in der Literatur zurückgegriffen werden. Es wurde darauf geachtet, daß immer eine Fehlerabschätzung oder eine Simulation durchgeführt wurde, damit die Ergebnisse sinnvoll interpretiert werden konnten. Oft konnten schon an der Referenzprobe (TDI in PMMA) sehr interessante Ergebnisse erhalten werden. So wurden z.B. neben der extrem hohen Photostabilität zwei verschiedene Populationen der Triplettlebensdauer gemessen. Die Position eines einzelnen TDI Moleküls konnte durch die Detektion vieler Photonen auf besser als 1 nm bestimmt werden. Die Analyse von zeitabhängigen Orientierungswinkeln deutet darauf hin, daß ein TDI Molekül in PMMA noch eine sehr geringe Wackelbewegung (~1°) ausführen kann. Bei der Analyse mehrerer 10000 Fluoreszenzspektren von einem TDI Molekül konnten spontane Änderungen der Fluoreszenzwellenlänge und der Schwingungskopplung beobachtet werden. Obwohl die Messungen in den Porenstrukturen aufgrund der geringeren Photostabilität nicht so präzise Ergebnisse liefern, konnten auch hier interessante Beobachtungen gemacht werden. Durch die Analyse der Orientierungswinkel vieler individueller Farbstoffmoleküle konnte gezeigt werden, daß die einzelnen Oxazinfarbstoffe in AlPO4-5 eine gaußförmige Verteilungsfunktion bezüglich ihres Tiltwinkels zur Porenrichtung aufweisen. Die zuvor erwähnten Messungen an einem Ensemble von Molekülen können die Form der Verteilungsfunktion nicht bestimmen. Aufgrund der Kenntnis einer gaußförmige Verteilungsfunktion kann auf ein statistisches Einbauverhalten der Farbstoffmoleküle in Defektstrukturen während der Synthese geschlossen werden. Auch in einem MCM-41 Kristall, dessen große Poren jeden beliebigen Einbauwinkel des Farbstoffes Cy5 erlauben würden, wird eine bevorzugte Orientierung beobachtet. Der Orientierungswinkel zur Porenrichtung zeigt auch hier eine gaußförmige Verteilungsfunktion. Interessanterweise wird bei der frontalen Ansicht auf die hexagonale Struktur (entlang der Bienenwabenstruktur) eine bevorzugte Orientierung auf die Flächen des Sechsecks beobachtet. Eine Ensemblemessung kann unmöglich diese bevorzugte Orientierung detektieren. Neben diesem statischen Verhalten zeigen einige wenige Moleküle auch eine Änderung der Molekülorientierung. Zwei individuelle Oxazin 1 Moleküle änderten ihre Orientierung in AlPO4-5 während der Messung spontan. Im Vergleich zu den anderen Oxazin 1 Molekülen besaßen diese beiden einen ungewöhnlich großen Orientierungswinkel gegen die Porenrichtung. Vermutlich wird die Bewegung durch einen größeren Defekt der Porenstruktur ermöglicht. Ein TDI Molekül im Inneren eines M41S Monolithen zeigte sogar eine mehrfache Drehung zwischen 3 verschiedenen Orientierungen.Eine Dynamik bezüglich des Ortes zeigten einzelne TDI Moleküle im M41S Monolith. Aufgrund der starken hydrophoben Eigenschaften des TDI kann davon ausgegangen werden, daß sich der Farbstoff immer noch im Inneren der Mizelle des Flüssigkristalls befindet, aus dem der Festkörper synthetisiert wurde. Die Diffusionsbewegung kann durch eine Serie von Fluoreszenzbilden mit dem konfokalen Mikroskop direkt verfolgt werden. Entgegen der erwarteten eindimensionalen Diffusion, die die hexagonale Struktur des Monolithen eigentlich erwarten läßt, wird eine isotrope Diffusion ohne Vorzugsrichtung beobachtet (D ~ 0,04 µm 2 /s). Im reinen Flüssigkristall dagegen ist die eindimensionale Diffusion vorhanden. Vermutlich werden die eindimensionalen Poren bei der Synthese der festen Silikatwand so stark verknäult, daß auf der beobachteten Längenskala ein Festkörper ohne Vorzugsrichtung entsteht. Auch die viel langsamere Diffusion im Vergleich zum reinen Flüssigkristall (D ~ 2 µm 2 /s) kann über diese Verknäulung der Poren erklärt werden. Schließlich wurden noch Messungen durchgeführt, um simultane Änderungen der Orientierung, Fluoreszenzspektren oder Triplettraten an einem einzelnen Farbstoffmolekül zu beobachten. Besonders die gleichzeitige Detektion von Fluoreszenzspektren und der Orientierung lassen sich experimentell gut durchführen. Zur Interpretation der Ergebnisse muß hier zwischen einer starken und einer schwachen Kopplung zwischen Gast und Wirt unterschieden werden. Bei einer polaren Probe wird eine starke Wechselwirkung zwischen Gast und Wirt erwartet. Diese müßte dazu führen, daß sich Änderungen in der Orientierung auch in geänderten Fluoreszenzspektren und umgekehrt bemerkbar machen. Bei einem geladenen Molekül wie Oxazin 1 wird solch eine starke Kopplung des elektronischen Systems an die polare AlPO4-5 Umgebung erwartet. Eine starke Änderung des Fluoreszenzspektrums könnte daher von einer Umorientierung des Farbstoffes herrühren. Bei den durchgeführten gleichzeitigen Messungen konnte aber nur spektrale Diffusion (±1-20 nm), aber keine gleichzeitige signifikante Umorientierung (>3°) beobachtet werden. Eine Erklärung für dieses Verhalten könnte die Bewegung des Gegenions des Farbstoffmoleküls sein, dessen Lage einen großen Einfluß auf die Fluoreszenzeichenschaften hat. Eine Umorientierung mit gleichzeitiger Detektion der Fluoreszenzspektren konnte jedoch nicht gemessen werden. Beide Ereignisse, Umorientierungen und spektrale Änderungen, konnten an TDI im M41S Monolith detektiert werden. Dabei zeigte sich aber, daß es sich hier um zwei unabhängige Prozesse handelt. Deutliche spektrale Sprünge (> 3 nm) korrelieren nicht mit deutlichen Umorientierungen (~60°). Eine geometrische Änderung des Farbstoffmoleküls oder der näheren Umgebung scheidet daher als Ursache für die spektrale Diffusion aus. Da hier aber eine schwache Wechselwirkung zwischen dem unpolaren TDI und der unpolaren Tensidumgebung vorliegt, werden auch keine starke Änderungen der Fluoreszenzspektren während der Umorientierung erwartet. Die spektrale Diffusion wird hier vermutlich von kleinen diffundierenden Teilchen (z.B. O2 oder Ionen) verursacht, die sich unabhängig von den Farbstoffmolekül bewegen können. Die Methode der Einzelmolekülspektroskopie liefert neue Einblicke in poröse Festkörper. Besonders durch die zeitabhängigen Untersuchungen können Informationen erhalten werden, die zuvor unter dem Mittelwert verborgen blieben. Ein kleiner Teil der Arbeit beschäftigt sich mit der Tieftemperaturfluoreszenz-spektroskopie an dem grün fluoreszierendem Protein (GFP). Dafür wurden der Wildtyp und verschiedene Varianten mit Mutationen in der Umgebung des zentralen Chromophors bei 2 K untersucht. Im Vergleich zur Raumtemperatur zeigten die Spektren bei tiefen Temperaturen deutlich mehr Struktur. Dadurch konnten verschiedene Sub-Zustände in den Varianten identifiziert werden. Bei fast allen Varianten konnten durch intensive Bestrahlung langwellig absorbierende Photoprodukte erzeugt werden, die erst bei etwa 50 bis 100 K wieder zerfallen. Obwohl eine relativ starke Elektron-Phonon-Kopplung beobachtet wird, ist an einigen ausgewählten Stellen auch hochaufgelöste Tieftemperaturspektroskopie wie spektrales Lochbrennen und Fluoreszenzlinienverschmälerung möglich. Durch Temperatur-Ableitungs-Spektroskopie werden an Wildtyp-GFP die Energien und Verteilungsfunktionen der Zerfallsbarrieren der metastabilen Photoprodukte bestimmt. Schließlich wurde durch temperaturabhängige Kurzzeitspektroskopie an Wildtyp-GFP der 'Excited state proton transfer' (ESPT) charakterisiert. Für diesen wird bis etwa 50 K eine thermische Barriere nach Arrhenius mit einer Aktivierungsenergie von ~2,3 kJ/mol gefunden. Unterhalb von etwa 50 K dominiert vermutlich ein Tunnelprozeß.

The chemical diffusion of fluorine in jadeite melt has been investigated from 10 to 15 kbars and 1200 to 1400°C using diffusion couples of Jadeite melt and fluorine-bearing jadeite melt (6.3 wt.% F). The diffusion profile data indicate that the diffusion process is concentration-independent, binary, F-O interdiffusion. The F-O interdiffusion coefficient ranges from 1.3 × 10−7 to 7.1 × 10−7 cm2/sec and is much larger than those obtained by Kushiro (1983) for Si-Ge and Al-Ga interdimision in jadeitic melts. The Arrhenius activation energy of diffusion is in the range of 36 to 39 kcal/mole as compared with 19 kcal/mole for fluorine tracer diffusion in a lime-aluminosilicate melt. The diffusivity and activation energy of F-O interdiffusion vary slightly with pressure, but the pressure dependence of F-O, Al-Ga and Si-Ge interdiffusion may be related to the relative volumes of the interdiffusing species for each pair. The magnitude of chemical diffusivity of fluorine is comparable to that of the chemical diffusivity of water in obsidian melts. The diffusivities of various cations are significantly increased by the addition of fluorine or water to a silicate melt. This fact, combined with the high diffusivity of fluorine, suggests that the F− ion is the principal diffusing species in dry aluminosilicate melts and that dissolved fluorine will accelerate chemical equilibration in dry igneous melts.