Podcasts about sio2

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Best podcasts about sio2

Latest podcast episodes about sio2

Coffee with Samso
Coffee with Samso - Cyclone Metals Limited (ASX:CLE) - A Green Iron Ore Business - Magnetite is the New Sheriff in Town.

Coffee with Samso

Play Episode Listen Later Mar 23, 2025 62:12


Coffee with Samso Episode 203 may well be one of the best ASX small-cap resource business in 2025, that is largely unknown to the general investing community. The Cyclone Metals Limited (ASX:CLE) is about the pedigree of the Iron Bear magnetite project. In Australia, the general ASX punter thinks of iron ore as haematite are greater than 62% Fe, but there is a new sheriff in town and he is called Magnetite. Where can you find a mineral resource business that is owned by a small cap junior with a market capitalisation of less than AUD $50M that has funding all the way through to mining and processing the high-grade iron pellets. Just remember that Cyclone Metals was a AUD $10M market cap company when it started the journey. The transitioning from haematite to magnetite in the iron ore industry is happening and it is largely driven by the depleting of high-grade haematite iron ore. - Paul Berend In this episode of Coffee with Samso we are talking to Paul Berend, Executive Director and CEO of Cyclone Metals Limited (ASX:CLE). Cyclone is a fascinating story of a junior aspiring to be a producer with a major, VALE, partnering with funding. A space in which most juniors would be struggling to find funding, CLE has a big brother taking care of all the bills. The Business of Cyclone Metals Limited. The steel producing industry is transitioning to low emission and the process of Direct Reduction (DR) steel production is the solution to a global reduction in emission for the typically high carbon emission business. . Direct Reduction steel production requires iron pellets that are very low in impurities and this is directly controlled by the quality of the source material. As Paul Berend explains, ....not all magnetite deposits are suitable for Direct Reduction Pellets which is why the Iron Bear deposit is perfectly aligned to allow this process to be achieved. Recent work by Cyclone Metals Limited has shown that the use of Direct Reduction on iron ore from Iron Bear can create iron pellets above 71% Fe content. According to Paul Berend, this is a very unique feature of the ore body. A feature that is not seen in many other iron ore resources and that includes those at Champion Iron. One statement that Paul proudly points out in the Coffee with Samso, and that is, The quality and the size of the Iron Bear Deposit moved the needled for VALE to take a position with Cyclone Metals. This is a great conversation with Paul Berend as he explains the story of Cyclone Metals clearly and in great details. Chapters: 00:00 Start. 00:08 Introduction. 04:10 Who is Paul Berend? 05:24 The Magnetite Story - Why Have We Not Embraced it Yet? 08:44 Transition of Value from Haematite to Magnetite. 09:41 Carbon Footprint of Magnetite. 10:07 Rise of Magnetite Projects? 10:33 Depletion of Brazilian High-Grade Iron Ores -The Reason why VALE is in CLE. 10:51 Importance of Direct Reduction (DR) Steel Production. 11:57 Only Way to Make Direct Reduction Steel - Premium of DR Pellets. 13:05 DR Pellet Market Comparison. 13:48 How Do You Make Direct Reduction Pellets. 15:14 Reason Why DR Pellet Production is Rare. 15:47 Comparison of Low Impurity Iron Deposits. 16:30 DR Player requires an ABILLITY To Reduce Impurities. 18:01 How much of the Current Resource will transition to Reserve Status. 19:08 Iron bear is a Low Stripping Ration deposit. 19:30 Metallurgy Will Increase the Economics of Iron Bear. 21:30 What is the main Business of Cyclone Metals ? Is it DR Production? 22:26 Is Iron Bear DR Capabilities why Vale is interested? 23:18 Iron Bear can supply high-grade iron ore all the way to DR levels. 25:07 How Did the Agreement with Vale Evolve ? 26:55 How important was the 10M ? 28:30 Earning a Mandate to Operate Socially. 29:25 Importance of the First Nations Conversations. 32:12 How Important is the relationship with First Nation Groups. 33:42 The Reasons why Vale could be the Reason for Success for Iron Bear. 36:24 Potentially One Technical Challenge for Iron Bear - Dry Tailings. 37:34 The Importance of Earning a Mandate To Operate 39:07 Twitter Shareholder Questions 39:27 Will the Trump Tariffs affect the Iron bear Business? 40:48 The Vison of Iron Bear - It is a Bigger project than Champion Iron. 41:58 Reducing the Carbon Footprint of a Manufacturing Hub in Northern America. 43:25 How much is the resource expected to be built up to? 43:58 Iron Bear is a Premium Magnetite project. 45:15 What cost will the hydroelectric power cost us per kilowatt? 46:51 Green Energy Narration - Magnetite Naturally Reduces Carbon Emission. 49:48 Discussion on iron ore prices. 54:23 Why is CLE still at 50M? 55:21 Why is the a feeling of disbelief in the Cyclone story? 58:02 The misunderstanding of the Iron Ore industry. 01:00:54 Takeaway. 01:01:18 Conclusion.   About Paul Berend Paul Berend brings over 25 years of leadership experience in the iron ore and steel industries, gained across blue-chip corporations and junior mining ventures. His corporate background includes senior roles such as GM Corporate Strategy at ArcelorMittal, GM Business Development at Rio Tinto Iron Ore and Director Australasia at Hatch. Paul is a passionate mining entrepreneur and was a founder and historic CEO of Trans-Tasman Resources Ltd (a titano-magnetite project in New Zealand ASX: MKR) and has played a key role in a number of private early-stage exploration ventures. In addition to his entrepreneurial work, Paul has a successful track record in turning around distressed producing mines and steel mills in difficult jurisdiction including Australia, PNG, Europe, GCC and Africa . He is a trusted advisor for Tier one natural resource companies, supporting operational, organisational and growth strategies. In this capacity, Paul's previous employers include McKinsey& Company and Partners in Performance. Paul has an MBA from HEC (Paris, France), a MSc and DEA (~PhD) in chemical process design and chemistry from ENSIC (Nancy, France), a bachelor's in applied mathematics and algebra from Harvard University (Cambridge, USA) and is a Graduate of the Australian Institute of Company Directors. He speaks native and English and French as well as professional German. About Cyclone Metals Limited Cyclone Metals owns and operates the Iron Bear magnetite iron ore project, formerly known as the Block 103 Project. The Iron Bear Project consists of ten licenses totalling 7,275 ha on 291 graticular Mineral Claims under the applicable Labrador and Newfoundland mining regulation, located near the Provincial border of Newfoundland and Labrador (NL) and Quebec (QC), approximately 30 km northwest of the town of Schefferville, QC and 1,200 km by air northeast of Montréal, QC. The Iron Bear properties are located within 25 km of an open access heavy haul railway which is directly connected to the Sept Isles and Pointe Noire iron ore export ports. In addition, the Iron Bear has potential access to cheap renewable energy from the Menihek hydro-plant located 75km away. These two factors substantially improve the prospects for eventual economic extraction of the Iron Bear mineral resource. Notably, large scale iron ore export operations currently operate in the Labrador Trough; including IOC (Rio Tinto), Champion Iron and Tata Steel; all sharing the same rail and port infrastructure. Highlights: World Class Iron Ore Project: Mineral resource of 16.6 billion tonnes containing 29.3% total Fe and 18.2% magnetic Fe, cut-off grade 12.5% magnetic Fe. Low OPEX: Estimated OPEX of USD 35.6/t3 FOB Pointe Noire for blast furnace concentrate due to access to low-cost hydropower Strategic Tier 1 Asset: Iron ore asset with flexible development scenarios and the potential to ramp up production to over 100 Mta Mining Friendly Jurisdiction and Proximity to Infrastructure: Iron Bear located in Canada, less than 25km from an open access heavy haul railway with proximity to low cost to hydro-power High Quality Product: Production of high quality magnetite concentrate grading 71,3% Fe and 1.1% SiO2 in industrial pilot plant Fast Track Project Development: Underpinned by the supply of bulk samples of DR and BF concentrates to mill clients by Q2 2024

The Auto Detailing Podcast
Are Torture Test Worth It? Do They Tell Us Anything?

The Auto Detailing Podcast

Play Episode Listen Later Oct 29, 2024 19:02


In this episode of The Auto Detailing Podcast, we dive into the world of torture testing! Long before launching my own product line and YouTube channel, I used torture tests to benchmark products, working with blenders to refine new formulas under extreme conditions. But do these tests really tell the full story? Tune in to hear why torture tests are only one piece of the puzzle and how we balanced them with real-world testing to create durable, versatile products like Tough As Shell. Plus, discover the science behind micro emulsion technology and the misconceptions around SiO2 percentages in detailing products.   Tough As Shell Torture Test: https://youtu.be/OmE-1XArSwA?si=ENU7psN8gRoLS1LI   My Favorite Detailing Products: https://jimbosdetailing.com/collections/best-sellers/products or on amazon - https://amzn.to/4edHuya  SUBSCRIBE TO MY CHANNEL: https://www.youtube.com/user/jbalaam?sub_confirmation=1  CONNECT WITH JIMBO: INSTAGRAM: https://www.instagram.com/jimbobalaam/ PODCAST: http://www.AutoDetailingPodcast.com FACEBOOK: http://www.Facebook.com/AutoDetailingPodcast or http://www.facebook.com/jimbo.balaam

Natuur en Wetenschap Ontdekt: Met Menno en Erwin
#134 O2 Het is een bijzondere stof, zowel in de biologie als in de chemie

Natuur en Wetenschap Ontdekt: Met Menno en Erwin

Play Episode Listen Later Sep 11, 2024 15:40


O2 - ZuurstofHet is een bijzondere stof, zowel in de biologie als in de chemie. Neem alleen die naam al, zuurstof, sauerstoff, oxy-gen. Allemaal identieke maar foutieve aanduidingen voor een stof waarvan ze ooit dacht dat het de vorming van zuren veroorzaakte. De invloedrijke “verkeerde naam”-gever was in de achttiende eeuw de beroemde Franse wetenschapper Lavoisier. Hij toonde onder andere aan dat zuurstof nodig was bij verbranding en ademhaling, en dat water behalve uit zuurstof ook uit waterstof bestaat.Voor ons mensen staat zuurstof natuurlijk gelijk met ademhalen, zuurstof die we uit de lucht halen in onze longen en via het bloed naar het hele lichaam transporteren. Daar gebruiken we zuurstof om heel efficiënt celbrandstof te vormen in de vorm van ATP (adenosinetrifosfaat). Dat is een proces dat veel effectiever is dan andere vormen van anaerobe ademhaling, zonder lucht, zoals bij bacteriën die sulfaat of nitraat gebruiken in plaats van zuurstof. Nog een andere energiewinnings-procedure zonder lucht is de gisting, bijvoorbeeld bij eencellige gisten. Die laten wij dat doen als we gist gebruiken bij processen als bier en wijn maken, of het laten rijzen van een brood. Omgekeerd is er in het ontstaan van het leven een ander proces ontstaan, dat van de fotosynthese. Onder invloed van licht konden al heel vroeg bacteriën uit kolzuurgas en water suikers en zuurstof aanmaken. Later eisten planten die rol op grote schaal op en dank zij hen kunnen de meeste planten en dieren op aarde nu vrijelijk ademhalen. Want vergis je niet, 's nachts hebben planten voor hun ademhaling ook zuurstof nodig, als ze in het donker geen fotosynthese kunnen bedrijven. Zuurstof komt heel veel en in heel veel vormen voor op aarde. Als meeste bekende gas O2, als gezegd in lucht met 21% een belangrijk aandeel. In de bergen loopt dat percentage wat terug, en dat geeft bij veel mensen dan ademhalingsproblemen. Heel veel zuurstof zit in water, H2O, maar ook in stikstofdioxide CO2, in carbonaten zoals in marmer (CaCO3) en in zand (Silicium oxide SiO2). Heel hoog in de lucht komt ook trizuurstof voor oftewel ozongas voor (O3), bekend van het afvangen van schadelijke straling uit de ruimte . Als het zuurstofatoom alleen voor komt als monozuurstof laat het een andere eigenschap van zuurstof zien, namelijk dat het heel reactief of zelfs agressief kan zijn zoals bij allerlei oxidatie-reacties. En met zuiver zuurstofgas moet men natuurlijk ook altijd oppassen, dat is hoogst brandbaar en explosief.. This is a public episode. If you would like to discuss this with other subscribers or get access to bonus episodes, visit www.mennoenerwin.nl

Proactive - Interviews for investors
Australian Silica Quartz Group starts drilling at Quartz Hill

Proactive - Interviews for investors

Play Episode Listen Later Jul 23, 2024 10:56


Australian Silica Quartz Group Ltd (ASX:ASQ) has started a diamond drill hole within the Quartz Hill mineral resource to collect samples for metallurgical testing. The Quartz Hill MGSi Project is 300 kilometres northwest of Townsville in Far North Queensland and contains a JORC 2012 resource of 17.3 million tonnes of MGSi quartz at 99.04% SiO2. Detailed quality testing and feasibility studies may enable this resource to support Quinbrook's proposed polysilicon manufacturing facility at the Lansdown Eco-Industrial Precinct in Townsville. As part of the Quartz Hill MGSi Project Scoping Study, ASQ is conducting metallurgical tests to characterise the expected quartz lump product. The drilling, performed by DDH1 Drilling Pty Ltd, uses a larger diameter PQ core size to a planned depth of 100 metres, twinning RC hole ASQQHRC010. Testing will include crushing, screening, pressure washing, scrubbing and ore sorting. The work program is funded by Quinbrook's July 2023 contribution to ASQ's exploration costs. ASQ is developing the project under a Project Development Heads of Agreement with Quinbrook Infrastructure Partners, a specialist energy transformation investment manager. Quinbrook plans to develop a polysilicon manufacturing facility and large-scale solar and battery storage project at the Lansdown Eco-Industrial Precinct, conditional on its allocation of 200 hectares in 2023. ASQ received $1 million from Quinbrook for the exclusive right to purchase 10 million tonnes of MGSi Quartz at a discount. Quartz Hill is on EPM 26702, 10 kilometres north of Mount Surprise. #ProactiveInvestors #AustralianSilicaQuartzGroup #ASX #ASQ #Silica #Quartz #MGSiProject #QuartzHill #LansdownEco-IndustrialPrecinct #Townsville #Quinbrook #Polysilicon #invest #investing #investment #investor #stockmarket #stocks #stock #stockmarketnews

Proactive - Interviews for investors
Cyclone Metals' Iron Bear Project poised to lead green steel revolution

Proactive - Interviews for investors

Play Episode Listen Later May 2, 2024 6:28


Cyclone Metals Ltd (ASX:CLE) CEO Paul Berend is back with Proactive after the company cut the ribbon on results from the first phase of metallurgical test-work at its Iron Bear Project in Canada. The team is celebrating after the program generated high-quality, high-yield iron ore concentrates —a crucial step in Cyclone's efforts to advance sustainable steel manufacturing through its flagship magnetite project. The pilot plant at Corem in Quebec City processed roughly half a tonne of source sediment, initially containing 29.1% total iron (Fe). Positively, Berend says the test results surpassed previous efforts, producing a direct reduction (DR) concentrate with a 71.3% Fe grade and 1.1% silicon dioxide (SiO2). This high-grade DR concentrate is pivotal for steel production via direct reduction technologies, aligning with the industry's shift towards more environmentally friendly practices. Additionally, the plant achieved a blast furnace concentrate with 69.8% Fe and 3.4% SiO2 and a reverse flotation (RF) concentrate grading 68.3% Fe and 4% SiO2. These results contribute to improved overall recovery rates and product quality while maintaining low levels of deleterious elements, essential for clean steelmaking inputs. What's more, Iron Bear's location near Schefferville on the border between Newfoundland and Labrador and Quebec provides strategic advantages. According to Berend, proximity to key infrastructure like an open-access heavy haul railway and potential access to renewable energy from the nearby Menihek hydro-plant enhances the project's economic viability. The project's magnitude is also a factor: a mineral resource update, released this month, puts the project at 16.6 billion tonnes of iron grading 29% total Fe and 18.2% magnetic Fe under JORC standards. These substantial resources, coupled with the recent pilot plant test-work, place Cyclone Metals at the forefront of developing next-generation low-carbon iron ore products. Moving ahead, the company has initiated phase two of the pilot program, planning to produce larger sample sizes for further testing and potential client trials as it works to foster partnerships for future offtake agreements. #ProactiveInvestors #CycloneMetals #ASX #IronBearProject #GreenSteel #SustainableManufacturing #MagnetiteMining #SteelProduction #MetallurgicalTesting #PilotPlant

BH Sales Kennel Kelp CTFO Changing The Future Outcome
Crystals and Sobriety: A Complementary Path to Healing and Wellness

BH Sales Kennel Kelp CTFO Changing The Future Outcome

Play Episode Listen Later Nov 29, 2023 13:20


Grandpa Bill Talks about Crystals for meditation: Here is a summary about Tourmaline Spring Water, with a focus on Amethyst and its benefits: Tourmaline Spring Water is naturally pure and does not require any treatment. It bubbles up from the ground in Maine and is bottled at the source, never coming into contact with sunlight. Amethyst is a crystal that is said to have many healing properties, including: The article also mentions that Grandpa Bill is a 60-year user of Tourmaline Spring Water and has experienced many benefits from drinking it. He believes that the water has helped him to maintain his health and well-being. Overall, the article suggests that Tourmaline Spring Water is a healthy and beneficial beverage that may offer a number of health benefits, including those associated with Amethyst. tourmalinespring.com/ Here is a more detailed breakdown of the assets of Amethyst: Amethyst Amethyst is a semiprecious gemstone that has been used for centuries for its healing properties. It is a variety of quartz that ranges in color from pale lilac to deep purple. Amethyst is known as the "stone of spirituality and sobriety." Physical Properties Chemical formula: SiO2 (silicon dioxide) Hardness: 7 on the Mohs scale Color: Pale lilac to deep purple Transparency: Transparent to translucent Crystal system: Hexagonal Metaphysical Properties Associated with the crown chakra Promotes spiritual awakening and connection Helps to clear negative energy and promote peace Enhances intuition and psychic abilities Can be used to relieve stress, anxiety, and insomnia Promotes healing and detoxification Uses of Amethyst Jewelry and gemstones Healing crystals Meditation and spiritual practice Feng shui and space clearing Water purification and energy enhancement Additional Benefits Amethyst is said to boost the immune system It can help to protect against electromagnetic pollution It can be used to relieve headaches and migraines It can help to improve sleep quality It can be used to increase focus and concentration Grandpa Bill's Experience with Amethyst Summit Spring & Tourmaline Spring Water Grandpa Bill has been drinking Tourmaline Spring Water for 60 years and believes that it has helped him to maintain his health and well-being. He attributes his good health to the water's purity and the healing properties of Amethyst. Overall, Amethyst is a powerful crystal with a wide range of benefits. It is a safe and natural way to promote healing and well-being. Throughout history, crystals have been revered for their purported ability to promote healing and well-being. Among the various crystals believed to possess unique properties, amethyst stands out as a prominent stone associated with sobriety. Amethyst, a semi-precious variety of quartz, has long been associated with spirituality, peace, and inner strength. Its calming and protective energy is believed to aid in overcoming addiction and maintaining sobriety. Benefits of Amethyst for Sobriety How to Use Amethyst for Sobriety Additional Crystals for Sobriety While amethyst is a prominent crystal for sobriety, other crystals can also provide support: Crystals as a Complementary Tool It is important to note that crystals should be used as a complementary tool in a comprehensive approach to sobriety. Seek professional guidance and support from addiction specialists, therapists, and support groups for a holistic approach to recovery. Crystals can provide valuable emotional and spiritual support, but they are not a substitute for professional treatment or evidence-based therapies. Breakdown more assets of Amethyst #crystalsforsobriety,#amethystforhealing,#sobrietyjourney,#crystalleadership,#soberliving,#addictionrecovery,#crystalleover,#crystalsofinstagram,#crystalhealingvibes,#crystalsforbeginners, --- Send in a voice message: https://podcasters.spotify.com/pod/show/bhsales/message

Detail Solutions Podcast
WOYM: Nano Surface Primers w/ Chris Racana from Dr. Beasley's

Detail Solutions Podcast

Play Episode Listen Later Oct 26, 2023 30:03


Took the audio from when I went to Sky's the Limit Car Care in Sanford, Fl a couple weeks back to make this episode. I was there to see my buddy Chris Racana from Dr. Beasley's because he was doing a demo for their NSP's. We got to hear how Jim came up with these NSP's and why they're different than other primer polishes. Chris also explains their AIO primer polish and how just by adding their SiO2 sealant you can get up to 12mos protection. Towards the end I added some audio from the detailers that were on hand to play with the NSP's and their reactions to removing scratches up to 1500 grit. Support this show and follow us on Facebook: @thedetailsolutionspodcast and @thedetailsolutionspodcastdiscussiongroup or on instagram: @detailsolutionspodcast and YouTube: The Detail Solutions Podcast You can now call our hotline and leave us a voicemail to be used on an upcoming episode, powered by Aenso North America. use code DSP for 20% off. Call 1-689-610-2275 You can find our sponsors at: www.vyperindustrial.com use code DSP to save an additional $25 off your purchase. www.detailersroadmap.com www.facebook.com/groups/detailersroadmap Make sure to mention you heard about them on the podcast for a special discount. www.oberkcarcare.com use code DSP (all caps) and receive 15% off your purchase. www.carsupplieswarehouse.com use code Solutions to save 15% off your first order. www.autofiber.com use code DSP for 10% off your purchase. For Towel of the Month memberships use the code totm25 for 25% off. www.detailingsuccess.com make sure to tell Renny you heard about on the podcast to get your discount. --- Support this podcast: https://podcasters.spotify.com/pod/show/detailsolutionspodcast/support

ALD stories podcast
Breaking Efficiency Records using ALD with Hele Savin – ALD Stories Ep. 28

ALD stories podcast

Play Episode Listen Later Oct 26, 2023 52:58


In Episode 28 of ALD Stories, Tyler is joined by Aalto University's Hele Savin. Hele is a professor in the department of Electronics and Nanoengineering where she uses ALD to engineer photovoltaics and semiconductor devices. In 2017, Hele was awarded the women's innovation prize from the Finnish parliament after fabricating a black silicon solar cell with a record-breaking 22.1% efficiency and currently uses ALD to create induced junction photodiodes with over 100% external quantum efficiency.     Hele and Tyler discuss how she was first exposed to ALD by Beneq, a mindset that using ALD was dirty, and how mind-blowing early ALD passivation results were. We also talk about why ALD oxides are better than thermal SiO2, the theoretical implications of breaking 100% EQE, and upcoming work in up conversion in her lab.    In this episode:    00:00 Intro  07:45 First experience with ALD  16:37 Passivation of Black Si Solar cells  29:52 ALD for Induced Junction Diodes  39:06 Theoretical Implications of High EQE  47:35 Future Up Conversion work

AGORACOM Small Cap CEO Interviews
HPQ's Breakthrough Fumed Silica Tech Attracts 2nd Leading Manufacturer - A Potential Game-Changer for the $2.2 Billion Market

AGORACOM Small Cap CEO Interviews

Play Episode Listen Later Sep 15, 2023 17:25


HPQ Silicon Inc. a pioneering force in green engineering processes for silica and silicon materials, has just marked a significant milestone in the world of Fumed Silica production. In an announcement that underscores the industry's growing interest, HPQ has signed an NDA with a second Leading Fumed Silica Manufacturer, solidifying the promise of its revolutionary Fumed Silica Reactor technology.   HPQ's wholly owned subsidiary, HPQ Silica Polvere Inc. has joined hands with technology provider PyroGenesis Canada Inc. to deliver a second batch of samples produced with the FSR technology to undergo third-party evaluation. The NDA signifies the strong third-party interest in HPQ's Fumed Silica material, a material of significant importance in various industries, including personal care, pharmaceuticals, agriculture, adhesives, construction, and automotive.   The significance of this milestone cannot be overstated. It confirms that HPQ Polvere's proprietary FSR technology is the only known method capable of transforming raw quartz (SiO2) into commercial-grade fumed silica in a single step, positioning them as a game-changer in a market estimated to be worth $2.2 billion as of last year.   Fumed silica, also known as Pyrogenic Silica, is renowned for its high surface area and low bulk density, making it a key ingredient in numerous applications. With global demand for fumed silica on a steady rise, it reached an estimated volume of 424,300 tonnes last year, HPQ Polvere's scalable production capability ranging from 250 to 2,500 tonnes per year puts them in a prime position to cater to the growing market needs.   Currently producing 50 kg per year at the lab scale, HPQ Polvere has ambitious plans to achieve 50 tonnes per year within the next 12 months and subsequently exceed 250 tonnes per reactor within the next 36 months. What sets HPQ apart from conventional manufacturing processes is its ability to directly transform quartz into fumed silica, dramatically reducing energy requirements and environmental impact.   The global market for fumed silica, previously reliant on Silicon Metal as feedstock, is evolving. HPQ's green and efficient approach not only makes it a cost-effective alternative but also addresses environmental concerns associated with traditional manufacturing processes, such as high CO2 emissions and hazardous by-products.   Bernard Tourillon, President and CEO of HPQ Silica Polvere Inc. and HPQ Silicon Inc., believes that the second NDA is a clear testament to the industry's recognition of their revolutionary process and its potential to reshape the fumed silica production landscape.   As HPQ continues its journey towards commercializing this ground-breaking technology, its dedication to expanding Fumed Silica production capacity and transforming the market remains unwavering. The second NDA signals that HPQ is on the cusp of transformative partnerships and innovations that can revolutionize the fumed silica industry, meeting growing global demand while maintaining a commitment to sustainability and environmental responsibility.

Pints & Polishing...an Auto Detailing Podcast
Detailing Deep Dive: 1 Year Ceramic Coatings. hyperCLEAN UNO Episode #749

Pints & Polishing...an Auto Detailing Podcast

Play Episode Listen Later Aug 19, 2023 21:50


Welcome to the hyperCLEAN UNO Deep Dive podcast! I'm Marshall, and joining me is Nick. You can find us at hypercleanstore.com or connect with us in the hyperCLEAN Specialist group on Facebook. We're excited to dive into one of our most popular products, the hyperCLEAN UNO, a one-year ceramic coating that has taken the automotive care industry by storm. In this episode, we're taking a closer look at the hyperCLEAN UNO ceramic coating. We'll explore its unique features, discuss its versatility, and uncover the secrets to achieving stunning results. Whether you're a seasoned professional or a DIY enthusiast, this episode is packed with insights that will help you make the most out of hyperCLEAN UNO. Marshall and Nick kick things off by delving into the product specifications. From its bead-forming characteristics to its extended flash time, we break down what sets hyperCLEAN UNO apart from other coatings. But what really makes this coating stand out? Nick shares his favorite aspect – the ease of use. We all know that applying a ceramic coating can be daunting, but hyperCLEAN UNO's user-friendly application process has turned skeptics into believers. The conversation then delves into the science behind hyperCLEAN UNO. Marshall and Nick discuss the coating's composition, highlighting its pure SiO2 nature and solvent-based formulation. This discussion takes us deeper into the coating's robustness and the reasons behind its lasting strength. Versatility takes center stage next. From various vehicle types to different paint systems, hyperCLEAN UNO proves its adaptability. Marshall shares personal anecdotes about when and where he loves to use the coating, particularly on challenging paint types like soft black clear coats. If you've ever struggled with these paint types, Marshall's insights might just be the solution you've been looking for. But where can you apply hyperCLEAN UNO? The hosts cover this question comprehensively, revealing a significant advantage of this coating – its application flexibility. Whether you're working in your own garage or at a client's location, hyperCLEAN UNO's applicability shines through. Marshall also offers practical advice on applying the coating in different conditions, ensuring optimal results every time. The discussion takes a turn toward application techniques. Nick and Marshall talk about their preferred methods, emphasizing the benefits of layering and applying the coating in a controlled manner. Nick shares valuable tips on achieving the best outcomes, especially for those looking for speed and efficiency. As the episode draws to a close, Marshall and Nick reflect on hyperCLEAN UNO's impressive track record over the past seven-plus years. The coating's dominance in the industry, its longevity of up to two years, and its ease of application all contribute to its continued success. So, whether you're a professional detailer or an avid car enthusiast, this podcast episode is your guide to mastering the art of applying hyperCLEAN UNO. From understanding its specs to harnessing its adaptability, join us on this deep dive into the world of one-year ceramic coatings.

Ingenios@s de Sistemas
Episodio 104 - Tecnología: CUARZO

Ingenios@s de Sistemas

Play Episode Listen Later Sep 8, 2022 9:52


Hoy es Jueves 8 de Septiembre y te voy a hablar de una tecnología para recordarte que en tecnolitas.com tienes un plan de asesoría tecnológica, que por tan solo 3 euros al mes, sin permanencia. Puedes hacer cualquier pregunta sobre blockchain, NFT, inteligencia artificial, realidad virtual, herramientas de software código abierto, implementación web, flujos de trabajo, negocios digitales, lo que necesites almacenamiento óptico 5D Las primeras demostraciones experimentales de la tecnología de almacenamiento óptico de datos en 5 dimensiones (5D) tuvieron lugar en 2010, en la Universidad de Kioto (Japón), y 2013, en la Universidad de Southampton (Reino Unido). Durante esta última demostración un grupo de investigadores especializados en optoelectrónica, una disciplina que se encuentra a medio camino de la óptica y la electrónica, logró almacenar un archivo de texto de 300 kbytes en un pequeño cristal de cuarzo. Y, posteriormente, también consiguió recuperarlo. La tecnologia actualmente disponible permite almacenar 360TB en un disco de carzo de 12cm, lo que viene a ser un CD. El primer ingrediente en el que nos tenemos que fijar es el cuarzo fundido, un cristal de óxido de silicio, conocido habitualmente como sílice, que se caracteriza por tener una estructura amorfa. El primer ingrediente en el que merece la pena que nos detengamos es el cuarzo fundido, un cristal de óxido de silicio (SiO2), conocido habitualmente como sílice, que se caracteriza por tener una estructura amorfa. La disposición irregular de las moléculas de los sólidos amorfos provoca que la intensidad de las fuerzas que describen las interacciones que existen entre ellas sea también irregular, por lo que estos sólidos no tienen un punto de fusión definido. Esto significa, sencillamente, que se funden en un intervalo de temperatura, y no cuando alcanzan un valor de temperatura preciso, por lo que habitualmente se deforman antes de fundirse completamente. Esta propiedad de los cristales de cuarzo fundido le da mucha resistencia y se asegura que podrían durar 13.800 millones de años a una temperatura máxima de 190º Celsius La clave del proceso de escritura: el láser de femtosegundo Desde las primeras líneas del artículo estamos dando vueltas a la idea de que esta es una tecnología de almacenamiento óptico de datos, por lo que, tal y como sucede con el CD, el DVD o el Blu-ray Disc, debe necesariamente estar involucrado un láser. Y sí, es así, pero el utilizado aquí es un dispositivo relativamente peculiar conocido como láser de femtosegundo muy parecido al que se utiliza en cirugía ocular para operar las cataratas, la presbicia, la miopía y otros defectos de refracción de la luz. Cada una de las celdillas de la nanoestructura en forma de rejilla de la que hemos hablado un poco más arriba tiene un tamaño aproximado de 20 nm, y, una vez que han sido manipuladas por el láser, actúan sobre la forma en que la luz se propaga a través de ellas de una manera muy similar a los filtros polarizadores que se utilizan, por ejemplo, en las gafas de sol. Curiosamente, el dispositivo que es necesario utilizar para leer la información codificada en estos soportes es una máquina que combina un microscopio óptico y un filtro polarizador que actúa, seleccionando la dirección en la que oscila el campo electromagnético generado por las ondas de luz.

Astro arXiv | all categories
Proton radiation damage tolerance of wide dynamic range SOI pixel detectors

Astro arXiv | all categories

Play Episode Listen Later Sep 8, 2022 0:47


Proton radiation damage tolerance of wide dynamic range SOI pixel detectors by Shun Tsunomachi et al. on Thursday 08 September We have been developing the SOI pixel detector ``INTPIX'' for space use and general purpose applications such as the residual stress measurement of a rail and high energy physics experiments. INTPIX is a monolithic pixel detector composed of a high-resistivity Si sensor, a SiO2 insulator, and CMOS pixel circuits utilizing Silicon-On-Insulator (SOI) technology. We have considered the possibility of using INTPIX to observe X-ray polarization in space. When the semiconductor detector is used in space, it is subject to radiation damage resulting from high-energy protons. Therefore, it is necessary to investigate whether INTPIX has high radiation tolerance for use in space. The INTPIX8 was irradiated with 6 MeV protons up to a total dose of 2 krad at HIMAC, National Institute of Quantum Science in Japan, and evaluated the degradation of the performance, such as energy resolution and non-uniformity of gain and readout noise between pixels. After 500 rad irradiation, which is the typical lifetime of an X-ray astronomy satellite, the degradation of energy resolution at 14.4 keV is less than 10%, and the non-uniformity of readout noise and gain between pixels is constant within 0.1%. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2209.03636v1

The Vox Markets Podcast
750: Bill Brodie Good of Alien Metals: Direct shipping Ore grades have been confirmed from bulk samples at Hancock

The Vox Markets Podcast

Play Episode Listen Later Jun 17, 2022 12:09


Bill Brodie Good, CEO & Technical Director of Alien Metals #UFO discusses how direct shipping Ore grades have been confirmed from bulk sample results at Hancock showing very low impurities consistent with excellent quality product. Highlights    ·  Metallurgical test work completed that produced an initial low cost flow sheet of simple crushing and screening for this material ·  Metallurgical test work confirming Direct Shipping Ore Grade product ·  High Grade Direct Shipping Ore Pilbara Fines product confirmed at a grade 62.7% Fe from the initial bulk sample from Ridge C Resource · Very low impurities consistent with excellent quality product including silica content (SiO2) < 4.1%, Aluminium content (Al2O3) < 2.77% and Phosphorus content (P) < 0.1% · Test work also indicated a potential for a Lump yield which can command a premium price over the fines above 62% Fe. ·  Marketing samples prepared and being dispatched to potential customers To read the full RNS click HERE

Researchat.fm
132. A Pile of Letters 2

Researchat.fm

Play Episode Listen Later Mar 27, 2022 68:59


過去2年分のお便りを紹介しました。Show notes TOKYO WARDROBE Ep21. Living in the base-21 world (Researchat.fm) … coelaが顕微鏡のワークショップに参加した感想を話す回。 Ep114. Logs of Logs (researchat.fm) … ”ブランドのカリスマ性とタトゥー/PCに貼るステッカー、大学の校章デザイン、スポーツチームのロゴデザイン、企業ロゴのデザイン、ポッドキャストのアートワークデザインについて話しました。” 東京外国語大学 … しびれる校章 横浜市鶴見区 … 区章?は鶴見区の横にあるやつっぽいです。 アメリカの救急車のマーク … “スター・オブ・ライフ(英: star of life、命の星)は「アスクレピオスの杖」を中心に青い六本の柱が突出したデザインのマーク。” NAIST Tシャツ … グツグツするTシャツ Ep10. The endgame keyboard (Researchat.fm) … “記念すべき第10回のエピソードは、キーボードを自作する楽しみ、研究における道具や技術を自作するか問題、ゲームコントローラーの改造、Hit Box、超解像顕微鏡の設計と組み立て、マンガについて話しました。” Ep66. Weaving a web of ideas (Researchat.fm) … “アイデアとノートの取り方、ノートの変遷、Zettelkasten (ノート作成方法)について話しました。” Ep57. All papers are created equal (Researchat.fm) … “科学論文の探し方、読み方とその楽しみ、そして理想の論文について三人で熱っぽく話しました。” ZEQUENZ/ジークエンス … SiO2さんにおすすめいただいたノート ユニボール ワン 0.38mm …SiO2におすすめいただいたボールペン Lily58 Pro … 自作キーボード Ep48. XXXXXYYYYY (Researchat.fm) … “レベルEのサキ王女編からスタートし、アメフラシ、ボネリムシ 、半倍数性、ヴォルバキアによる破壊、ゾウリムシ、カモノハシ、オスの三毛猫など、真核生物における多様な性決定システムと性染色体について話しました。” Docker R Markdown Jupyter Notebook history researchat.book … 未だ見ぬ大作? Ep12. Open Source Cola … “ボストンのコーヒー事情、コーヒーのこだわり、希少性の高い食品や物の価値、地球温暖化の原因、お便り機能の実装、おすすめの本紹介、書店や図書館の魅力、科学研究におけるデータ共有の難しさ、オープンソース化されたコーラの作り方などについて話しました。” Ten simple rules to improve academic work–life balance Ep70. Existing Legend … “現存する伝説の武器について話しました。” ぼおるぺん古事記 Ep17. Ghost in the half-shell … “カルビーの新ジャガイモ・ぽろしりの凄さ、個体サイズと染色体数・細胞数の関係性、バオバブバー閉店、世界の武器、象、ゲーム開発や研究における職人技について話しました。” iBiology … 最強の動画シリーズ Conversations in Genetics … 最高の動画シリーズ MITのOpen Course … あとはこれをひたすら流します。 Image Cast Editorial notes 引き続きお便りお願いします!(soh) 遅くなりましたが、お便りありがとうございます。(tadasu) 頂いたメッセージへの当時の回答をメモっておこうと思いました。 (coela)

Dayconmusic
Episode 201: Brother Soul - MidweekWorday Chill Mix 141

Dayconmusic

Play Episode Listen Later Mar 24, 2022 124:57


Brother Soul - Midweek Workday Chill Mix 141 #midweekworkdaychillmix w/Brother Soul (Philly/Baltimore/UK)Wednesday 3pm to 5pm BST11am to 1pm EST #brothersoul #iambrothersoul #iamdjbrothersoul We invite ONE and ALL to Come and Check out our New Home.  Join us in the chat room. https://loveabrotherradio.orgOn the Go? Find us on the following Apps:Android: RadioDroid Apphttps://play.google.com/store/apps/details?id=net.programmierecke.radiodroid2&hl=en_GB&gl=USiphone & Android: Radio Gardenhttp://radio.garden/visit/salford/FgTlcFdb Find us on Telegram @loveabrotherradioSpread This Love. Amy Grady - D.O. c/oJ aka Brother SoulShow Playlist1.Un-Love You (Ralf Gum Main Mix) Ralf Gum & Sio2. Intoxicating (Audrey Loud Remix) Daniel Marques3. Bonita - Ninetoes4. Beat It - Senor Coconut5. Remedios - Pizeta   6. Darkest Hour - Sevdaliza7. Crying - Roy Orbison & k.d King8. Play That Funky Music - Wild Cherry9. Rock The Boat - The Hues Corporation10. Stop and think - The Trammps11. Boogie Oogie Oogie - G.Q 12. Everlasting Love - Carl Carlton13.Tsop (The Sound Of Philadelphia) - MFSB14. Lotta Love - Nicoleete Larson15. Only The Strong Survive - Billy Paul16. The Love i Lost - Herold Melvin & The Blue Notes17. Disco Nights - G.Q18. Lets Groove - Earth, Wind & Fire19. Relight my fire - Dan Hartman 20. I Cant stand the rain - Eruption21. Turn the Beat Around - Vicki Sue Robinson22. You should be Dancing - Bee Gees23. Love Really Hurts Without You - Billy Ocean 24. This is it - Melba Moore25. Take Good care of yourself - The three Degrees26. Im in the mood for dancing - The Nolans27. september - Earth, Wind & fire 28. Hes Killing me ( ohh - wee) Patti Austin

The Vox Markets Podcast
613: Christian Taylor-Wilkinson of Altona Rare Earths: Phase 2 drilling campaign to proceed after positive results from Phase 1 at Monte Muambe

The Vox Markets Podcast

Play Episode Listen Later Mar 17, 2022 8:37


Christian Taylor-Wilkinson, CEO of Altona Rare Earths #ANR discusses how the positive results from the Phase 1 drilling campaign at the Monte Muambe REE asset has given them confidence to proceed on a Phase 2. SUMMARY * Phase 1 results show above average REE levels * Two new mineralised areas identified * Phase 2 resource drilling to start in April 2022 and last for up to 12 months * Phase 2 will deliver: maiden Mineral Resource Estimate, metallurgical testing and scoping study * Phase 1 total spend was £580,000 and Phase 2 costs expected to be approx. £1.2 million * Full Intertek assay results expected by May 2022   About Altona Rare Earths Plc Altona Rare Earths Plc is a mining exploration company focused on the evaluation, development and extraction of Rare Earth Element (REE) metals in Africa. It owns a REE mining project in Mozambique; the Monte Muambe Project, a Light REE mining project in the southwest of the country, where exploration work commenced on 1 October 2021. The Company is in the process of investigating other REE opportunities in Africa. Notes on the use of pXRF analyser for rare earths exploration at Monte Muambe: The Hitachi X-Met8000 is a pXRF equipped with a 50kv anode and specific programmes to enable the detection and quantification of Nd, Pr, La, Ce and Y, as well as of light elements relevant to carbonatites such as K, Mg and Si. Duplicate 3m composite RC samples were prepared using plastic cups covered by a mylar film and assayed under standard conditions using both the light elements programme (30s assay time) and the rare earths programme (60s assay time). Regular checks and calibration are done using a SiO2 blank and various CRMs. In the current conditions, pXRF results give a good indication as to the degree to which samples are mineralised, and are usable as a decision tool, but are not final and should be considered with caution.

Mind & Matter
Chris Weikart: Medical Glass, Materials Science & the COVID Vaccine Supply Chain | #50 | Supported by SiO2

Mind & Matter

Play Episode Listen Later Dec 23, 2021 57:37 Transcription Available


Nick Jikomes talks to materials scientist Dr. Chris Weikart, who  is currently chief scientist at SiO2, an advanced materials science company that combines chemistry and engineering to create containers and surfaces for use by biotechnology, genomics, diagnostics, and consumer products companies. They discuss how SiO2 created a new kind of vaccine vial, which combines both glass and plastic that are superior for storing and transporting biologics, such as vaccines. SiO2 is currently producing an enormous number of these vials for Moderna's mRNA vaccines for COVID-19. Chris described how the vials are made, and what they're made of, as well as what materials science is and how important it is to society. This conversation also gives you a sense for different parts of the COVID vaccine supply chain and how they fit together.USEFUL LINKSSign up for the weekly Mind & Matter newsletter[https://mindandmatter.substack.com/]Learn more about SiO2[https://www.sio2ms.com/]Download the podcast & follow Nick at his website[https://www.nickjikomes.com]Buy books by M&M guests[https://linktr.ee/mindandmatter_books]Athletic Greens, comprehensive daily nutrition (Free 1-year supply Vitamin D w/ purchase)[https://athleticgreens.com/partner/d3...]Organize your digital highlights & notes w/ Readwise (2 months free w/ sub)[https://readwise.io/nickjikomes/]Follow & Support Nick's work[https://linktr.ee/trikomes]Learn more about our podcast sponsor, Dosist[https://dosist.com]Support the show (https://www.patreon.com/nickjikomes)Support the show (https://www.patreon.com/nickjikomes)

FUTUREPROOF.
From Material Sciences to Talent Recruitment: How the Pandemic Changed Everything

FUTUREPROOF.

Play Episode Listen Later Oct 13, 2021 28:08


COVID has changed the world to such an extent over the past year and a half, and of course it's not something that anyone would ever wish on society, but there have been some interesting developments - a lot of them positive. One of those innovations comes from SiO2, a little-known material science company from Alabama that received a $143 million investment from the US government to tackle the vaccine vial shortage. To date, they have provided the government with vials for over 100 million covid vaccine doses. I spoke to the company's president, Lawrence Ganti [at the 1:01 mark], about why the future of drugs will be biological — and the long-term positive effects that COVID could bring to pharma and life sciences. My conversation with Lawrence got me thinking about the new kinds of jobs that might have been created on account of the pandemic, which then had me thinking about how companies are finding the talent they need in a post-COVID world. To help clue us in on that front, I turned to Evan Sohn [at the 11:11 mark]. He's the Chairman and Chief Executive Officer of Recruiter.com, an on-demand recruiting platform that combines AI and video job-matching technology with the world's largest network of small and independent recruiters. We talked about how the pandemic changed how companies recruit, what the post-COVID world of work looks for job candidates, and much more. As always, we welcome your feedback. Please make sure to subscribe, rate, and review on Apple Podcasts, Spotify, Stitcher, and Google Play - and make sure to follow us on Facebook and LinkedIn!

Wings Mobile Detailing
How to find the best coating amongst all the labels? - Wings Mobile Detailing 101

Wings Mobile Detailing

Play Episode Listen Later Oct 6, 2021 15:05


With all these new coating brand “technilogy” out there it may be difficult to find which ones are the best! What if I tell you they are all mostly the same. All ceramic coatings is composed of (SIO2) and all Graphee coating have Graphene resin. - Catch, some companies market their product better, but it doesn't mean it's better. What to look for when picking a brand of ceramic coating and should you even worry about that? Acreditation to get ceramic coating. --- Support this podcast: https://anchor.fm/wings-mobile-detailing/support

KeyStone Stock Talk Podcast
Stock Talk Podcast Episode 157

KeyStone Stock Talk Podcast

Play Episode Listen Later Sep 27, 2021 44:27


This week, in our, ask us anything segment we answer a couple of questions about your stock portfolio including how many stocks you should own and the simple process of constructing an equity portfolio. We also have 2 YSOT segments for your listening pleasure. Our first YSOT this week came in from a listener on Hollister Biosciences (HOLL: CNX), which operates as a licensed manufacturer and distributor of recreational cannabis and cannabis products, and distributes its products through an arrangement with a cannabis distributor to licensed cannabis vendors in California and Arizona. The listener believes the company is significantly undervalued; we will let you know if we agree. Our second YSOT is on HPQ-Silicon Resources Inc. (HPQ:TSX-V) - a Quebec-based silicon solutions company that offers innovative silica (SiO2), silicon (Si) based solutions and is developing a unique portfolio of high value-added silicon (Si) products sought after by battery and electric vehicle manufacturers. We take a quick look at the business.

Speed 6 Podcast
#34: Types of Shampoo & Death to Noodle Mitts

Speed 6 Podcast

Play Episode Listen Later Aug 6, 2021 64:14


Pure, decon, acidic, SiO2. gloss enhancing, wax-containing, abrasive, even graphene! There are a lot of shampoos on the market these days, but are they any good? We also discuss different types of wash media, along with our preferences. --- Send in a voice message: https://anchor.fm/thedetailingpodcast/message

Here The Future
#024: Making the Covid Vaccine Indestructible - Lawrence Ganti

Here The Future

Play Episode Listen Later Mar 28, 2021 30:27


Lawrence is the President of SiO2 Materials Science, a company focused on three core segments: Pharmaceuticals, Molecular Diagnostics, and Consumer Healthcare. Given a $143 million investment grant from the U.S. government, SiO2 is on a mission to tackle the vaccine vial shortage. They hold over 300 patents and are known for their unique glass like barrier for application onto any plastic surface so as to increase its durability. Throughout the Covid Crisis, demand for this material has surged, presenting a novel opportunity for SiO2. To date, they have supplied vials for over 100 million Covid vaccine doses. Lawrence holds a Bachelors of Science in Entrepreneurship from Babson College and was previously the CEO of Innoplexus. Lawrence joins us to discuss the products that SiO2 offer, how SiO2 scaled during Covid, and trends in the Materials Science space. https://www.sio2ms.com/

The Bio Report
As COVID-19 Vaccines Ship, One Company Brings Innovation to the Vials

The Bio Report

Play Episode Listen Later Dec 17, 2020 24:56


As potential vaccines for COVID-19 approached approval, the focus has been on the safety and efficacy of candidates. Now that vaccines have been approved, attention has been shifting to the complex logistical challenges of manufacturing, distributing, and delivering vaccines to patients. The process has opened up visibility into many aspects of the supply chain that are usual taken for granted. One of those aspects are the vials used to store that vaccines and the threat that a shortage of glass bottles could cripple distribution efforts. SiO2 Material Science, which won a $143 million U.S. government contract for vials and syringes, is applying semiconductor technology to create plastic containers with a nano coating of glass inside. We spoke to Christopher Weikart, head of scientific affairs and chief scientist for SiO2 Material Science, the considerations that go into a vaccine vial, the technology SiO2 is using, and why it offers advantages over traditional glass and plastic.

Cool Things Entrepreneurs Do
Making Waves in Bio and Pharma Packaging with Chris Weikart

Cool Things Entrepreneurs Do

Play Episode Listen Later Nov 5, 2020 33:45


About Chris Weikart, PhD    As Chief Scientist at SiO2 Materials Science, Dr. Weikart is responsible for managing both internal and external R&D initiatives, including collaborative studies at domestic and international universities, customers and research organizations. He has oversight for the company’s innovation strategy and the development of new technologies to address customer-centric problems. Dr. Weikart works closely with SiO2’s Scientific Advisory Board and technical consultants for launching new technical initiatives. He also works closely with the intellectual property department to provide technical support for patent filings and trade secret preservation. He is the technical ambassador and spokesman at conferences, customers, and regulatory bodies. Dr. Weikart earned a PhD in chemical engineering from the University of Missouri-Columbia. He worked in Central Research at the Dow Chemical Company for 12 years in various R&D, engineering and leadership roles. Dr. Weikart earned a 6 Sigma Black Belt.     About SiO2   SiO2 Materials Science is a materials science company with deep roots in chemistry and engineering. We use proprietary, advanced, material science, to bring our client’s innovation to life. Our patented technology applies a unique glass-like barrier onto any plastic surface. Our products are engineered to combine the durability and dimensional precision of plastic with the physical and barrier properties of glass. We provide an end to end solution from the design, engineering, molding, barrier coating, to packaging for our clients. Our most prominent solutions take the form of primary packaging for biological drugs and blood collection tubes for genomic testing and liquid biopsies.   https://thomsinger.com/podcast/Si02  

AGORACOM Small Cap CEO Interviews
HPQ An Emerging Low Cost Silicon Metal Producer Goes Beyond The Presentation

AGORACOM Small Cap CEO Interviews

Play Episode Listen Later Oct 18, 2019 70:09


HPQ Silicon Resources Inc. is a TSX-V listed company developing, in collaboration with industry leader PyroGenesis (TSX-V: PYR) the innovative PUREVAPTM “Quartz Reduction Reactors” (QRR), a truly 2.0 Carbothermic process (patent pending), which will permit the transformation and purification of quartz (SiO2) into Metallurgical Grade Silicon (Mg-Si) at prices that will propagate its significant renewable energy potential. HPQ is also working with industry leader Apollon Solar to develop: Porous silicon wafers manufacturing using PUREVAP™ Silicon (PVAP Si) that can be used as anode for solid-state Li-ion batteries; and A metallurgical pathway of producing Solar Grade Silicon Metal (SoG Si) that will take full advantage of the PUREVAPTM QRR one-step production of high purity silicon (Si) and significantly reduce the Capex and Opex associated with the transformation of quartz (SiO2) into SoG-Si.

AGORACOM Small Cap CEO Interviews
HPQ Gen2 Testing Confirms PUREVAP™ Process Can Significantly Reduce the Cost of Making Silicon Metal

AGORACOM Small Cap CEO Interviews

Play Episode Listen Later Jun 18, 2019 26:24


HPQ Silicon Resources Inc. is focuses on becoming the lowest cost producer of Silicon Metal and a vertically integrated and diversified High Purity, Solar Grade Silicon Metal (SoG Si) producer and a manufacturer of multi and monocrystalline solar cells of the P and N types, required for production of high performance photovoltaic conversion. HPQ’s goal is to develop, in collaboration with industry leader PyroGenesis (TSX-V: PYR) the innovative PUREVAP™ “Quartz Reduction Reactors (QRR),” a truly 2.0 Carbothermic process (patent pending), which will permit the transformation and purification of quartz (SiO2) into Metallurgical Grade Silicon Metal (Mg Si) at prices that will propagate it clean energy potential.

Sains Sekitar Kita
Sains Sekitar Kita: Mengapa Jawa lebih subur dibanding Sumatra? Petunjuknya ada di abu gunung api

Sains Sekitar Kita

Play Episode Listen Later Aug 19, 2018 6:32


Pengendara sepeda motor di Yogyakarta menerobos abu vulkanik dari letusan gunung Kelud, 14 Februari 2014. Setyo Adhi Pamungkas/ShutterstockGunung Anak Krakatau di Selat Sunda erupsi 576 kali pada Sabtu lalu, dengan tinggi letusan mencapai 100-500 meter dari puncak kawah. Letusan ini memuntahkan abu vulkanis, pasir, lontaran batu pijar, dan suara dentuman. Anak Krakatau merupakan satu dari 129 gunung api aktif di Indonesia. Letusan gunung adalah fenomena alamiah yang berulang dan tidak perlu dikhawatirkan berlebihan selama penduduk di sekitar gunung mengikuti langkah-langkah evakuasi yang dilakukan oleh pemerintah. Dengan puluhan gunung api aktif, Indonesia adalah negara vulkanik teraktif dan paling terancam, tapi juga mungkin lumbung pupuk paling subur di dunia. Menurut Biro Pusat Statistik pada 2017, setengah populasi orang Indonesia ada di Jawa. Sumatra yang panjangnya dua kali lipat Pulau Jawa hanya menampung 20% populasi. Apakah ini ada hubungannya dengan populasi gunung? Sumatra punya 30 gunung api, sementara Pulau Jawa punya 34 gunung api. Apakah karakter abu vulkanis keduanya berbeda hingga menghasilkan kesuburan yang berbeda? Dian Fiantis, ahli tanah dari Universitas Andalas, memberikan jawaban mengapa tanah di Pulau Jawa lebih subur dibanding tanah Sumatra. Erupsi gunung di Pulau Jawa lebih banyak menghasilkan unsur hara seperti kalsium (Ca) dan Magnesium (Mg) yang dibutuhkan oleh tanaman. Sedangkan silikon dioksida (SiO2) yang lebih banyak dimuntahkan gunung di Sumatra tidak dibutuhkan banyak oleh tanamannya. Zat ini tersedia banyak tapi tidak dibutuhkan. Selain itu, curah hujan di Jawa Tengah dan Jawa Timur lebih rendah dibanding pantai barat Sumatra sehingga unsur-unsur yang menyuburkan lebih lama bertahan di tanah Jawa. Edisi ke-22 Sains Sekitar Kita ini disiapkan oleh Hilman Handoni dan narator Malika. Selamat mendengarkan!

Love & Light Live Crystal Healing Podcast
Healing Properties of Golden Tiger Eye: A Crystal for Personal Power & Energy

Love & Light Live Crystal Healing Podcast

Play Episode Listen Later Jun 5, 2018 16:13


A Crystal Message about the Healing Properties of Golden Tiger's Eye: "I am motivated by my divine purpose and I manifest your vision with ease." Common Healing Properties of Golden Tiger's Eye: Enhances grounding Increases psychic skills Encourages the rising of the kundalini through the chakras Promotes energetic protection Stimulates compassion Aids you in sorting through details and completing tedious tasks Helps you pull together many details in order to make sense of a whole Aids in removing negative habits Instills self-confidence and inner-strength - a personal empowerment stone Promotes equality and integrity Stabilizes energy Banishes depression Heals the eyes Balances disorders of the reproductive system Aids in the energetic healing of broken bones Helps you succeed on tests and exams Encourages success in business meetings Colors: Bands of shimmering gold, brown, bronze, and gray/black Associated Chakras: 2nd (Sacral Chakra) or 3rd (Solar Plexus Chakra) Zodiac Signs: Virgo, Leo Elements: Air, Earth Companion Flowers: Yellow Coneflower Companion Essential Oil: Sunflower Companion Stone: Rainforest Jasper Common Origins: South Africa, Australia Wanna’ Get Science-y? Click Here to get information about the chemical composition, hardness, streak, etc. of this crystal from one of my favorite sites!   /*   More About Golden Tiger's Eye: Tiger’s eye is a form of quartz in which the SiO2 crystals have grown together with asbestos fibers, giving it a distinctive silky sheen. We’ll talk here about the basic golden form, but there are several related stones: Tiger’s eye is a great stone for putting “pedal to the metal,” taking charge of what you want and bringing it into reality. It’s also a traditional stone for warding off the evil eye. Since it contains asbestos, please don’t use it for elixirs. Tiger's Eye Lore: The association between “The Eye of the Tiger” and bravery didn’t start with Survivor’s song or Stallone’s movies. It goes back at least as far as the Roman Legion, where soldiers wore tiger’s eye jewelry into battle for protection and courage. But this wasn’t its only use, even then. Divination was very popular in Rome, and soldiers in the field could use tiger’s eye as a quick method to gain insight and clarity — and, of course, a soldier often doesn’t have time to wait. Military men also used this stone as an early warning to detect potential deception. Tiger’s eye contains luminous layers of asbestos within a quartz matrix, forming complex but regular patterns, making it excellent for scrying. The directionality of these pieces has a magic to it as well; the pyramid pictured here would be great for channeling universal energy! There’s much more to tiger’s eye than just “the thrill of the fight.” (And now I’m going to have that song in my head for the rest of the day…). Learn to use crystals with POWERFUL Crystal Affirmations! YES PLEASE! SIGN ME UP  

Love & Light Live Crystal Healing Podcast
Healing Properties of Clear Quartz: A Crystal for Amplifying Energy & Intention

Love & Light Live Crystal Healing Podcast

Play Episode Listen Later Apr 4, 2018 18:51


A Crystal Message about the Healing Properties of Clear Quartz: "Feel your mind expand with clarity as I help you tune in and become one with the world around you." Common Healing Properties of Clear Quartz: Powerful for energizing the physical and energetic bodies Assists with healing the physical, mental, emotional, and spiritual bodies Purifies and cleanses the physical and energetic bodies Amplifies your intentions for manifesting and co-creating with the universe Assists you with any kind of spiritual work Promotes mental clarity Amplifies energy in crystal layouts or grids Enhances your inner vision and intuition Balances and aligns the chakra centers Protects you energetically Colors: Clear, Colorless Associated Chakras: All Zodiac Signs: Leo, Virgo, Aries Elements: Air, Water, Fire Companion Flowers: Trillium Companion Essential Oil: Tea Tree Companion Stone: Lapis Lazuli Common Origins: Madagascar, Brazil, Arkansas (USA), India Notes: Also known as Rock Crystal.  The ancient Romans thought Quartz crystals were made from ice that was so frozen it would never thaw or melt. Wanna’ Get Science-y? Click Here to get information about the chemical composition, hardness, streak, etc. of this crystal from one of my favorite sites!   /*    The staff from my new age shop, Mimosa Books & Gifts, had this to share: Quartz is a common and abundant mineral that comes in a variety of colors and forms. The stone we usually call quartz is clear rock crystal. This is quartz without visible impurities, which naturally forms into a brilliant six-sided prism, coming to a point at the end. It’s an oxide of silicon, and therefore a semiconductor. People have been drawn to quartz for literally millennia, using it for tools, jewelry, containers and works of art. Metaphysical references from the Romans and earlier identified quartz as permanently frozen ice. It is composed of SiO2. In its purest form, silicon dioxide is clear quartz, also called rock crystal. But when this mineral contains trace elements of other minerals, or when the Earth’s inner forces have changed its form, we see a huge variety in appearance. When quartz is completely pure, it is either clear, white, or a combination of both. White, or “milky” quartz, is simply clear quartz that contains tiny gas bubbles. The more colorful varieties of quartz come from small particles of metallic elements that became trapped in the quartz as it hardened. Some are natural, some artificial. Metaphysical uses: Clear quartz naturally amplifies energy. It wants to clean and purify everything in its path, including all the body’s chakras, as well as other items in the physical and spiritual worlds. One of the best ways to experience the power of a quartz crystal in everyday life is to use it to help amplify personal intentions — decide what you want, and use your crystal to magnify your intention until it manifests. (As always, do this in such a way that your intention remains focused on the greatest good, not simply short-term desires.)  Quartz wands are especially powerful when used this way. Clear quartz also has excellent spiritual qualities. Clear quartz is great for directing and focusing energy. Depending on how you plan to use your crystals, you could start with either a single quartz wand or a handful of small quartz points. Learn to use crystals with POWERFUL Crystal Affirmations! YES PLEASE! SIGN ME UP

Love & Light Live Crystal Healing Podcast
Healing Properties of Blue Tiger’s Eye (Hawk’s Eye): A Crystal for Power & Communication

Love & Light Live Crystal Healing Podcast

Play Episode Listen Later Jan 30, 2018 10:10


A Crystal Message about the Healing Properties of Blue Tiger's Eye: "I feel myself making way for clarity, as if seeing something for the very first time.  I am able to look deeper into a situation to see the truth that lies behind the facade.  I'm prepared for what is revealed and I know that it is for my highest good."   Common Healing Properties of Blue Tiger's Eye: Keeps you grounded Enhances your psychic skills Encourages the rising of the kundalini through the chakras (but only if you are ready for it) Creates a protective shield around your aura Encourages inner-strength Enhances feelings of compassion in those with an overdeveloped masculine side Helps you to sort through details especially when you're completing tedious tasks Helps banish negative habits Aids you while working through depression Energetically supports the healing of the eyes Facilitates healing of male reproductive disorders Energetically assists in healing broken bones Facilitates strength in communication Instills peace and calming Helps you work through and overcome fears of all kinds   Colors: Deep blackish-blue with gray-blue in alternating bands that shimmer in the light Associated Chakras: Solar Plexus (3rd), Throat (5th), Third Eye (6th) Zodiac Signs: Leo, Capricorn Elements: Air, Water, Earth Companion Flowers: Stargazer Lily Companion Essential Oil: Vetiver Companion Stone: Red Tiger's Eye Common Origins: Africa Notes: This stone is also known as Hawk's Eye, Falcon's Eye, or as Crocidolite Wanna’ Get Science-y? Click Here to get information about the chemical composition, hardness, streak, etc. of this crystal from one of my favorite sites!   /* More About Blue Tiger's Eye: Like other forms of tiger's eye, the blue variety (often called Hawk's Eye) is a form of quartz in which silky asbestos fibers have been trapped within the SiO2, giving it a distinctive sheen. Don't worry!  Even though it contains asbestos, it is safe to handle in its polished or tumbled form (the fibers are trapped within the Quartz). The form of asbestos is Crocidilite, an iron-bearing mineral that's normally blue in color. When that iron rusts before it gets trapped within the silica, it turns brown and results in golden tiger's eye. But if the silica infiltrates the fibers before the iron has time to rust, the blue color is retained, resulting in Blue Tiger's Eye. Blue tiger’s eye contains crocidolite (blue asbestos) fibers. When the iron in these fibers oxidizes, the stone bearing it becomes red or golden tiger’s eye. Combining the raw power of Tiger's Eye with the blue color association gives an interesting and useful combination of metaphysical characteristics. All tiger's eye is great for removing habits that no longer serve, plowing through details of your to-do list, and getting down to business. Tiger’s Eye is a great stone for putting “pedal to the metal,” taking charge of what you want and bringing it into reality. It’s also a traditional stone for warding off the evil eye. It can make you feel grounded, empowered and protected. Along with this, the blue variety boosts the power and effectiveness of all forms of communication. When it comes to setting and achieving goals, communication is an important factor that's sometimes overlooked. Another traditional use is for averting the evil eye. Since it contains asbestos, please don’t use it for crystal elixirs. One way to use this stone: Blue Tiger's Eye makes a great pocket stone -- one you'll want to keep with you throughout the day. It's a great choice for a palm stone or worry stone, but a small polished piece in your pocket or bag can serve just as well. You might want to keep it on your desk as you work, study, and manage various projects in your life. Then when you're done for the day,

Serious Inquiries Only
SIO2: Trump's Cabinet: Filling the Swamp

Serious Inquiries Only

Play Episode Listen Later Dec 29, 2016 46:45


Direct Download In this episode, we start taking a look Trump's picks for his cabinet members; beginning with his choices for Secretary of State and Secretary of the Treasury. Just to be sure we have some perspective, we go over the job descriptions and look at some of the individuals that held these positions during the Obama and G.W. Bush administrations. You might say we have some concerns... Will ‘drain the swamp’ be Trump’s first broken promise?- Politco Rex Tillerson, an Aggressive Dealmaker Whose Ties With Russia May Prompt Scrutiny- NY Times Trump’s Treasury Secretary Pick is a Lucky Man. Very Lucky. -ProPublica   Support us on Patreon at:  patreon.com/seriouspod Follow us on Twitter: @seriouspod Facebook:  https://www.facebook.com/seriouspod

消灭无聊
【科学人·太空】火星上的生命证据,在地球上找到了?

消灭无聊

Play Episode Listen Later Dec 21, 2016 11:17


文/溯鹰(构造地质学博士、科学松鼠会成员)2016年,可能会成为人类发现地外生命的拂晓之年。之所以这么说,是因为最近在地球上作出的一些地质新发现,把10年前在火星上拍到的一组“老照片”重新拉回到了人们眼前。如果两者之间真有靠谱关联的话,那说不定真就会搞出一个大新闻。10年前,火星上发现蛋白石故事得从这10年前的老照片说起。早在大名鼎鼎的好奇号(Curiosity)登陆火星之前,他的前辈——勇气号(Spirit)火星车,就在火星上拍到了一种不太正常的石头。这些石头长着枝丫,一如纤纤手指;或者包成结核,形似浅海生物。勇气号用自带的小型热辐射光谱仪(Mini-TES, Miniature Thermal Emission Spectrometer)测量了它的矿物成分,发现它们是无定形态的二氧化硅(SiO2),也就是我们常说的蛋白石(Opal)。这些火星蛋白石的发现,给当年的行星科考界带来过不少热度。火星上发现二氧化硅这类东西,表明这颗寂静荒凉的星球,曾经也存在过活跃的热液活动。勇气号火星车在火星上发现的蛋白石。图片来源:Nature Communications你可能会问,二氧化硅在地壳里不是挺泛滥的么?毕竟,跟蛋白石一样同属二氧化硅的石英(Quartz, SiO2),在岩石圈里是主要的造岩矿物。火星车发现二氧化硅,有什么令人稀罕的呢?之所以你觉得地壳里SiO2泛滥,是因为你身在地球。在其它3颗岩质行星(火星、金星、水星)上,这东西可就难得一见了。一个比较冷门的科学事实是,太阳系的4大岩质行星,除了地球以外,都没经历过强烈的化学分异。我们都知道,岩质星球的主要成分是氧(O)、硅(Si)、铝(Al)、铁(Fe)、镁(Mg)、钙(Ca)。虽然Si和O占了头筹,但后头那4位,也都不是容易打发的主儿。它们是阳离子,要想让它们“安生”下来——也就是以电中性化合物的形式稳定赋存,得需要足够多的阴离子来与它们配对。仔细看看这6种元素,想找个靠谱点儿的阴离子,还真就只能打Si和O的主意。于是,我们有了SiO42-。当我们把这个酸根分配给一个个阳离子的时候,便有了所有岩质星球上最主要的物质成分——硅酸盐。可SiO2不是硅酸盐,它是简单氧化物。它的存在,是一个环境里Si与O过饱和的标志。言外之意就是,当Mg、Fe、Ca这些阳离子全都被消耗或者移除之后,如果还有剩余的Si和O,它们才会以独立的形式相结合,最终形成SiO2。得益于活跃了几十亿年的软流圈,得益于一经开启便从未停息的板块构造,地球——这个太阳系特立独行的个体——创造了一部足以碾压其它行星的大地动力史。在几十亿年的岁月里,地球的地幔一直在源源不断地往地壳输送岩浆,而岩浆上涌的过程又恰恰是一个化学分异的过程:Mg和Fe的硅酸盐因为结晶早、比重大而率先从岩浆中沉淀下去,最终让剩余的岩浆富含Si和O。当它们到达地球表层并结晶成岩时,就把大量的SiO2带入了地壳。这是我们今天能在地球的地壳里看到大量石英的本质原因。其他3颗星球呢?不好意思,诞生不久,就早早冷却掉了。像地球这样几十亿年如一日的持续演化,对于它们来说简直就是天方夜谭。它们早早地关闭了对流系统,关闭了深部物质出入地表的窗口。所以,在这些早已陷入沉眠的星球上,我们见到的最多的东西,不外乎也就只有镁铁质的岩石了。可勇气号终究还是在火星上发现了SiO2。经过层序律的限定,表明它们形成于45亿-35亿年前的诺亚纪。那个时候,火星内部还没有彻底冷却,其构造活跃程度说不定跟地球还有得一拼。既然火星没有星球规模的宏观分异,那么这些特立独行的二氧化硅,肯定来自于局部发生的构造-热事件。考察这些蛋白石的上下地层可以发现,它正好位于两套镁铁质火山岩之间。地质学家利用将今论古和将地论天两大原则,推断当时火星上富含热液活动。高温热液能够轻易地把上下火山岩地层里的Fe离子和Mg离子从岩石的分子骨架中淋滤掉,从而把Si和O筛出来。这样,过饱和的Si和O就凝固成了独立的蛋白石。至于这些热液活动产物代表什么沉积环境,鉴于那个时候也没拿出什么关键性的证据,渐渐也就没有了下文。毕竟,火星车时不时都会弄些大新闻传给地球,火星上能吸引大家的地方,实在太多了。在类似的火星开拓之旅中,人们掀过了21世纪的头一个10年。人们见证了勇气号的沉眠,也见证了好奇号的降临。只要火星车的车辙仍在这片红色的荒原上缓缓延伸,荧惑之星的故事,便必然还会继续。如今,地球上找到叠层石很快,时间的箭头就指向了2016年,坐标也从火星移回到了我们的地球。来到南美洲,来到智利,来到一片叫做El Tatio的地区。地球上的El Tatio地区遍布着热液喷发口。图片来源:Nature Communications这里是地球上最大的海洋板块——太平洋板块向南美大陆俯冲的最前锋。剧烈的板块挤压,塑造了狭长而宏伟的安第斯造山带。大地构造运动孕育了活跃的火山作用,让喷气口和热泉漫布在这个狭长的国度上。它们喷出的热液给地表带来了形形色色的沉淀物。智利又恰好处在盛行西风带,缺水干燥的环境特征,让这些在地表极不稳定的化学物质统统完整地保留了下来。El Tatio地区因此也成为地球上一个良好的天然实验室,研究者用这片土地上的特征,来模拟数十亿年前的火星气候环境。很快地,人们就在这块有趣的地方,找到了跟勇气号当年在火星上看到的东西十分相似的物质。如果仅仅是成分上的类似,比如都是蛋白石的话,这个故事就没什么意思了。El Tatio地区的这些二氧化硅沉淀物不仅在形貌上与火星蛋白石极为相似,更关键的是,在Mini-TES光谱上,也表现出了极为相似的谱线特征。而地球其他地方的SiO2沉积物(比如美国的黄石地区),在谱线上的偏离就明显大得多。无论从宏观形貌上,还是微观特征上,El Tatio地区和火星上的沉积物之间都表现出了一种极为密切的相关性。这些SiO2沉积物裹了一层微米级的石盐(Halite,NaCl)包壳,被认为是喷孔热液活动的关键证据——它们是富含氯离子的热液在输出通道上留下的沉淀物。石盐极易溶于水,但得益于El Tatio地区独特的干燥气候特征,这些含有微米级石盐壳的沉积物有幸能够保留下来。如果用它来解释火星上那些相关性良好的对应物,人们就可以大胆地说明,勇气号找到的,很可能就是火星当年一个活跃的热液喷发孔。在地球的热液喷发口附近,寄寓着大量营化学生活的细菌。这些细菌很原始,事实上,它们就是所有地球生命的最初形态。早在地球环境剧变无常的太古时代,这些微小的原始细菌就围在富含化学物质的喷发口附近,靠热液中的化学能量来营生。随着小细菌们世代更替,他们的新陈代谢产物也一叠摞一叠,逐渐摞成一种宏观的构造——叠层石。El Tatio地区这些蛋白石沉积物的独特骨架,就是细菌世代更替中所留下的叠层石产物。在地球上,还真没有太多无机地质行为,能够像细菌一样塑造出结构如此精细独特、成分上又如此不易保存的天然作品。在相同的尺度上对比火星上的蛋白石(左列)与地球上的层叠石(右列),可以看到它们具有明显的相似性。图片来源:Nature Communications现在,问题来了:火星呢?我们的确看到了类似的、具有精细枝杈状结构的蛋白石;也从形貌和岩石化学上,很谨慎地解释了它们可能形成于热液喷发孔环境。那么剩下的问题就是:除了细菌,还有别的成因么?至少,在地球上,我们很难找到与生物无关的成因。出于天生的严谨,科学家还是很保守地把火星上这套相关的蛋白石结构称之为“Potential Biosignature”,即潜在的生命活动特征。按照NASA的定义,所谓潜在的生命活动特征,是指一个物体、一种物质或者一种结构,它们可能形成于生物成因,但在明确的结论得出之前,尚需要人们去收集更多的数据来完善佐证。科学家的话虽然说得滴水不漏,但对于我们这些吃瓜群众,为何不大胆猜测一下呢?反正我们看热闹从来就不怕事太大。如果后续研究最终没能确认生物成因,OK,两个行星上太阳照常升起。可反过来,万一这个研究真的就触碰到了火星上生命的真相,那么2016年的这个尾巴,可能就要永载史册了。而我们,则是时代的亲历者。

消灭无聊
【科学人·太空】火星上的生命证据,在地球上找到了?

消灭无聊

Play Episode Listen Later Dec 21, 2016 11:17


文/溯鹰(构造地质学博士、科学松鼠会成员)2016年,可能会成为人类发现地外生命的拂晓之年。之所以这么说,是因为最近在地球上作出的一些地质新发现,把10年前在火星上拍到的一组“老照片”重新拉回到了人们眼前。如果两者之间真有靠谱关联的话,那说不定真就会搞出一个大新闻。10年前,火星上发现蛋白石故事得从这10年前的老照片说起。早在大名鼎鼎的好奇号(Curiosity)登陆火星之前,他的前辈——勇气号(Spirit)火星车,就在火星上拍到了一种不太正常的石头。这些石头长着枝丫,一如纤纤手指;或者包成结核,形似浅海生物。勇气号用自带的小型热辐射光谱仪(Mini-TES, Miniature Thermal Emission Spectrometer)测量了它的矿物成分,发现它们是无定形态的二氧化硅(SiO2),也就是我们常说的蛋白石(Opal)。这些火星蛋白石的发现,给当年的行星科考界带来过不少热度。火星上发现二氧化硅这类东西,表明这颗寂静荒凉的星球,曾经也存在过活跃的热液活动。勇气号火星车在火星上发现的蛋白石。图片来源:Nature Communications你可能会问,二氧化硅在地壳里不是挺泛滥的么?毕竟,跟蛋白石一样同属二氧化硅的石英(Quartz, SiO2),在岩石圈里是主要的造岩矿物。火星车发现二氧化硅,有什么令人稀罕的呢?之所以你觉得地壳里SiO2泛滥,是因为你身在地球。在其它3颗岩质行星(火星、金星、水星)上,这东西可就难得一见了。一个比较冷门的科学事实是,太阳系的4大岩质行星,除了地球以外,都没经历过强烈的化学分异。我们都知道,岩质星球的主要成分是氧(O)、硅(Si)、铝(Al)、铁(Fe)、镁(Mg)、钙(Ca)。虽然Si和O占了头筹,但后头那4位,也都不是容易打发的主儿。它们是阳离子,要想让它们“安生”下来——也就是以电中性化合物的形式稳定赋存,得需要足够多的阴离子来与它们配对。仔细看看这6种元素,想找个靠谱点儿的阴离子,还真就只能打Si和O的主意。于是,我们有了SiO42-。当我们把这个酸根分配给一个个阳离子的时候,便有了所有岩质星球上最主要的物质成分——硅酸盐。可SiO2不是硅酸盐,它是简单氧化物。它的存在,是一个环境里Si与O过饱和的标志。言外之意就是,当Mg、Fe、Ca这些阳离子全都被消耗或者移除之后,如果还有剩余的Si和O,它们才会以独立的形式相结合,最终形成SiO2。得益于活跃了几十亿年的软流圈,得益于一经开启便从未停息的板块构造,地球——这个太阳系特立独行的个体——创造了一部足以碾压其它行星的大地动力史。在几十亿年的岁月里,地球的地幔一直在源源不断地往地壳输送岩浆,而岩浆上涌的过程又恰恰是一个化学分异的过程:Mg和Fe的硅酸盐因为结晶早、比重大而率先从岩浆中沉淀下去,最终让剩余的岩浆富含Si和O。当它们到达地球表层并结晶成岩时,就把大量的SiO2带入了地壳。这是我们今天能在地球的地壳里看到大量石英的本质原因。其他3颗星球呢?不好意思,诞生不久,就早早冷却掉了。像地球这样几十亿年如一日的持续演化,对于它们来说简直就是天方夜谭。它们早早地关闭了对流系统,关闭了深部物质出入地表的窗口。所以,在这些早已陷入沉眠的星球上,我们见到的最多的东西,不外乎也就只有镁铁质的岩石了。可勇气号终究还是在火星上发现了SiO2。经过层序律的限定,表明它们形成于45亿-35亿年前的诺亚纪。那个时候,火星内部还没有彻底冷却,其构造活跃程度说不定跟地球还有得一拼。既然火星没有星球规模的宏观分异,那么这些特立独行的二氧化硅,肯定来自于局部发生的构造-热事件。考察这些蛋白石的上下地层可以发现,它正好位于两套镁铁质火山岩之间。地质学家利用将今论古和将地论天两大原则,推断当时火星上富含热液活动。高温热液能够轻易地把上下火山岩地层里的Fe离子和Mg离子从岩石的分子骨架中淋滤掉,从而把Si和O筛出来。这样,过饱和的Si和O就凝固成了独立的蛋白石。至于这些热液活动产物代表什么沉积环境,鉴于那个时候也没拿出什么关键性的证据,渐渐也就没有了下文。毕竟,火星车时不时都会弄些大新闻传给地球,火星上能吸引大家的地方,实在太多了。在类似的火星开拓之旅中,人们掀过了21世纪的头一个10年。人们见证了勇气号的沉眠,也见证了好奇号的降临。只要火星车的车辙仍在这片红色的荒原上缓缓延伸,荧惑之星的故事,便必然还会继续。如今,地球上找到叠层石很快,时间的箭头就指向了2016年,坐标也从火星移回到了我们的地球。来到南美洲,来到智利,来到一片叫做El Tatio的地区。地球上的El Tatio地区遍布着热液喷发口。图片来源:Nature Communications这里是地球上最大的海洋板块——太平洋板块向南美大陆俯冲的最前锋。剧烈的板块挤压,塑造了狭长而宏伟的安第斯造山带。大地构造运动孕育了活跃的火山作用,让喷气口和热泉漫布在这个狭长的国度上。它们喷出的热液给地表带来了形形色色的沉淀物。智利又恰好处在盛行西风带,缺水干燥的环境特征,让这些在地表极不稳定的化学物质统统完整地保留了下来。El Tatio地区因此也成为地球上一个良好的天然实验室,研究者用这片土地上的特征,来模拟数十亿年前的火星气候环境。很快地,人们就在这块有趣的地方,找到了跟勇气号当年在火星上看到的东西十分相似的物质。如果仅仅是成分上的类似,比如都是蛋白石的话,这个故事就没什么意思了。El Tatio地区的这些二氧化硅沉淀物不仅在形貌上与火星蛋白石极为相似,更关键的是,在Mini-TES光谱上,也表现出了极为相似的谱线特征。而地球其他地方的SiO2沉积物(比如美国的黄石地区),在谱线上的偏离就明显大得多。无论从宏观形貌上,还是微观特征上,El Tatio地区和火星上的沉积物之间都表现出了一种极为密切的相关性。这些SiO2沉积物裹了一层微米级的石盐(Halite,NaCl)包壳,被认为是喷孔热液活动的关键证据——它们是富含氯离子的热液在输出通道上留下的沉淀物。石盐极易溶于水,但得益于El Tatio地区独特的干燥气候特征,这些含有微米级石盐壳的沉积物有幸能够保留下来。如果用它来解释火星上那些相关性良好的对应物,人们就可以大胆地说明,勇气号找到的,很可能就是火星当年一个活跃的热液喷发孔。在地球的热液喷发口附近,寄寓着大量营化学生活的细菌。这些细菌很原始,事实上,它们就是所有地球生命的最初形态。早在地球环境剧变无常的太古时代,这些微小的原始细菌就围在富含化学物质的喷发口附近,靠热液中的化学能量来营生。随着小细菌们世代更替,他们的新陈代谢产物也一叠摞一叠,逐渐摞成一种宏观的构造——叠层石。El Tatio地区这些蛋白石沉积物的独特骨架,就是细菌世代更替中所留下的叠层石产物。在地球上,还真没有太多无机地质行为,能够像细菌一样塑造出结构如此精细独特、成分上又如此不易保存的天然作品。在相同的尺度上对比火星上的蛋白石(左列)与地球上的层叠石(右列),可以看到它们具有明显的相似性。图片来源:Nature Communications现在,问题来了:火星呢?我们的确看到了类似的、具有精细枝杈状结构的蛋白石;也从形貌和岩石化学上,很谨慎地解释了它们可能形成于热液喷发孔环境。那么剩下的问题就是:除了细菌,还有别的成因么?至少,在地球上,我们很难找到与生物无关的成因。出于天生的严谨,科学家还是很保守地把火星上这套相关的蛋白石结构称之为“Potential Biosignature”,即潜在的生命活动特征。按照NASA的定义,所谓潜在的生命活动特征,是指一个物体、一种物质或者一种结构,它们可能形成于生物成因,但在明确的结论得出之前,尚需要人们去收集更多的数据来完善佐证。科学家的话虽然说得滴水不漏,但对于我们这些吃瓜群众,为何不大胆猜测一下呢?反正我们看热闹从来就不怕事太大。如果后续研究最终没能确认生物成因,OK,两个行星上太阳照常升起。可反过来,万一这个研究真的就触碰到了火星上生命的真相,那么2016年的这个尾巴,可能就要永载史册了。而我们,则是时代的亲历者。

Fakultät für Physik - Digitale Hochschulschriften der LMU - Teil 05/05
Photonic waveguides evanescently coupled with single NV-centers

Fakultät für Physik - Digitale Hochschulschriften der LMU - Teil 05/05

Play Episode Listen Later Dec 18, 2015


The interaction of photons with individual quantum systems is a very fundamental process in physics. Thereby, the emission rate as well as the angular emission pattern of a quantum emitter are not only a function of intrinsic properties of the emitter itself, but are also strongly modified by its surrounding. For instance, by restricting the optical modes which are allowed at the position of the dipole, the emission rate can be strongly modified and the emitted photons can be directed into specific optical modes. This effect can be demonstrated by the interaction of a single optically active quantum emitter with the strongly confined optical mode of a single-mode dielectric waveguide. Efficient coupling of the emitter to the dielectric structure can be achieved by placing the quantum emitter inside the evanescent field of the guided mode. This evanescent field coupling mechanism is discussed and demonstrated experimentally. A single nitrogen-vacancy center (NV-center), hosted in a nanodiamond is deterministically coupled to a tapered optical fiber (TOF) via the evanescent field of its guided mode (coupling efficiencies exceeding 30% are predicted). By employing an AFM-based nanomanipulation technique, the diamond nanocrystal is placed on the nanofiber waist of the TOF. Beforehand, the diamond nanocrystal has been characterized to guarantee that it hosts only one fluorescing NV-center. While the diamond nanocrystal is optically exited, single photon fluorescence of the NV-center is detected at both outputs of the tapered optical fiber. This verifies the evanescent coupling of the emitter to the guided mode. In order to quantify the coupling, the comparison of the emission rate into free space with the rate into the fiber yields that 10.0(5) of the emitted photons are coupled into the tapered optical fiber. In the determination of this value, the orientation of the emitting dipoles and the emission pattern, which are modified by the TOF, have been considered. The NV-center features a broad emission spectrum which can be used to investigate the wavelength-dependence of the coupling. Comparing the spectra of the emission into the fiber mode with the emission into free space modes roughly resembles the expected wavelength dependency of the coupling efficiency. The evanescent coupling and the deterministic positioning of preselected fluorescing diamond nanocrystals, which has been demonstrated with the TOF, can be applied to other waveguide structures as well. Dielectric single-mode waveguides made of Ta2O5 on a SiO2 substrate promise similar coupling efficiencies to tapered optical fibers (above 30%). With the design of the on-chip wave-guiding structure being flexible, the combination with other optical on-chip elements is feasible, rendering it a promising platform for on-chip photonic experiments. Test structures of this waveguide design are realized using lithographic processes and are characterized. These waveguides are equipped with inverted taper structures to allow efficient off-chip coupling with butt-coupling to standard single-mode fibers. The evanescent coupling of a single quantum emitter to a singe optical mode can be used to efficiently collect emission of the quantum emitter. This can help building a compact single photon source and is beneficial for the optical read-out of the quantum emitter's internal degree of freedom, which can be either used as probe (sensing) or as information-storage. Utilizing the high coupling efficiency, for instance, the non-linearities of the quantum system can be exploited to build a single photon transistor. The evanescent coupling is very broadband (about hundred nanometers), allowing to efficiently collect emission from broadband emitters like the NV-center, but it can also be used for multi-wavelength manipulation schemes.

Fakultät für Physik - Digitale Hochschulschriften der LMU - Teil 05/05
Development of high-damage threshold dispersive coatings

Fakultät für Physik - Digitale Hochschulschriften der LMU - Teil 05/05

Play Episode Listen Later Jul 9, 2014


Whether it is to form an optical cavity, to control dispersion, or merely to transport the laser beam, multilayer mirrors are fundamental components of every ultrafast laser system. The performance of current state of the art ultrafast high-power lasers in terms of pulse energy is often restrained by optical breakdown of multilayer coatings. One way to overcome this problem is to increase the size of the laser beam, but this is usually undesirable, as it rises the costs and the footprint of the laser system. Therefore, increasing the optical resistance of multilayer mirrors is essential to the development of cost- and space-efficient lasers. In turn, this requires a thorough understanding of the mechanisms behind optical damage. In this work, we have studied the ultrafast optical breakdown of dispersive mirrors, as well as that of other multilayer thin-films, in three different regimes: (i) at 500 Hz repetition rate with 30 fs pulses, at a central wavelength of 800nm; (ii) at 11:5MHz repetition rate with 1 ps pulses, at 1030 nm; (iii) at 5 kHz repetition rate with 1:4 ps pulses at 1030 nm. The results from (ii) and (iii) have been compared side by side. In addition, a novel technique for dispersion measurements has been developed. In the femstosecond regime, the samples have been: single layer coatings made of Au; Ag; Nb2O5; SiO2;Ta2O5 and mixtures of Ta2O5 with silica in different concentrations; and different dispersive coatings, consisting of SiO2 as the low-index material and different high-index materials (Nb2O5; Ta2O5; HfO2). We have also given a suggestion as to what is the best approach to increase the damage threshold of thin-film dielectric coatings. The ultrafast optical breakdown of multilayer thin-films has been investigated at MHz repetition rate and high average power. The optical breakdown threshold of three different types of coatings has been measured. All samples have been coated with either TiO2, Ta2O5, HfO2, or Al2O3 as high-index material and with SiO2 as low-index material. The same samples have been measured also at kHz repetition rate. The results obtained in both regimes have been compared. The band gap dependencies of damage threshold in both cases were linear. However, the one retrieved at kHz rate was steeper than its MHz counterpart. This is an interesting finding, which must be investigated further. The developed method for dispersion measurements has been based on the location of resonance peaks in a Fabry-Perot-type of interferometer. By simultaneously processing data obtained at different spacer thicknesses, we were able to obtain superior resolution compared to the conventional method.

Fakultät für Physik - Digitale Hochschulschriften der LMU - Teil 04/05
Attosecond dynamics of nano-localized fields probed by photoelectron spectroscopy

Fakultät für Physik - Digitale Hochschulschriften der LMU - Teil 04/05

Play Episode Listen Later Jul 17, 2013


This work focuses on the interaction of few-cycle laser pulses with nanosystems. Special emphasis is placed on the spatio-temporal evolution of the induced near-fields. Measurements on carrier-envelope-phase (CEP) controlled photoemission from isolated SiO2 nanospheres are taken by single-shot velocity map imaging (VMI) combined with CEP tagging. The obtained photoelectron spectra show a pronounced dependence on the CEP and extend to unexpectedly high energies. Comparison with numerical simulations identify the additional Coulomb forces of the liberated electron cloud as an effective additional acceleration mechanism for distinct trajectories. For larger spheres, an asymmetry in the field distribution is classically predicted. This asymmetry is also observed in the photoelectron momentum distributions. The mapping between position and momentum space in the VMI approach are investigated by analyzing the correlation of the photoelectron's birth and detection position. In a second set of experiments, photoemission at intensities exceeding 10^14 W/cm^2 from isolated nanospheres of different composition (SiO2, ZrO2, TiO2, Si, Au) is examined by stereo time-of-flight spectroscopy. It is found that the measured cutoff energies scale non-linearly with laser intensity depending on the material properties of the nanosystem. A trend towards a unified behavior for high intensities is observed indicating a drastic change in optical properties within the duration of the few-cycle laser pulse. The charge carrier generation mechanisms that could lead to such a transient effect are discussed. For a better understanding of the interaction of few-cycle fields with nanosystems, a direct access to the temporal evolution of (plasmonic) near-fields is highly desirable. The efforts on the realization of nanoplasmonic attosecond streaking spectroscopy are presented. Numerical simulations are used to identify the influence of the inhomogeneous near-field distributions on the streaking process. First experimental results obtained from Au nanotips show clear streaking features of sub-micron localized near-fields. The near-field oscillations are found to be phase offset as compared to reference measurements. The exact origin of the streaking features of the Au tip and possible improvements of the experimental approach are discussed.

Physics of Microfabrication: Front End Processing
Lecture 06: Oxidation and the Si/SiO2 Interface: Deal/Grove Model, Thin Oxide Models

Physics of Microfabrication: Front End Processing

Play Episode Listen Later Apr 7, 2008 74:12


Physics of Microfabrication: Front End Processing
Lecture 07: Oxidation and the Si/SiO2 Interface: 2D Effects, Doping Effects, Point Defects

Physics of Microfabrication: Front End Processing

Play Episode Listen Later Apr 7, 2008 71:42


Fakultät für Physik - Digitale Hochschulschriften der LMU - Teil 02/05
Crystal structure of fiber structured pentacene thin films

Fakultät für Physik - Digitale Hochschulschriften der LMU - Teil 02/05

Play Episode Listen Later Oct 22, 2007


This PhD thesis presents a technique based on the grazing incidence crystal truncation rod (GI-CTR) X-ray diffraction method used to solve the crystal structure of substrate induced fiber structured organic thin films. The crystal structures of pentacene thin films grown on technologically relevant gate dielectric substrates are reported. It is widely recognized, that the intrinsic charge transport properties in organic thin film transistors (OTFTs) depend strongly on the crystal structure of the organic semiconductor layer. Pentacene, showing one of the highest charge carrier mobilities among organic semiconductors, is known to crystallize in at least four polymorphs, which can be distinguished by their layer periodicity d(001). Only two polymorphs (14.4 Å and 14.1 Å), grow as single crystals and their detailed crystal structure has been solved with standard crystallography techniques. The substrate induced 15.4 Å polymorph, the so called pentacene thin-film phase, is the most relevant for OTFT applications, since it grows at room temperature on technologically relevant gate dielectrics. However, the crystal structure of the pentacene thin-film phase has remained incomplete as it only grows as a fiber structured thin film. In this thesis, the GI-CTR X-ray diffraction technique is extended to fiber structured thin films. The X-ray diffraction experiments were carried out at the synchrotron source beamline W1 at HASYLAB in Hamburg, in order to obtain enough diffraction data for the determination of the crystal structure as pentacene thin films only grow as ultra thin films with crystal grains as small as 0.4μm. Pentacene thin films are also known to be sensitive to environmental conditions, such as light and oxygen. For this reason, the X-ray synchrotron measurements were performed in-situ. A portable ultra high vacuum growth chamber equipped with a rotatable sample holder and a beryllium window was built in order to perform X-ray measurements of up to four samples right after the thin film growth process without breaking the vacuum. Parallel to this, a versatile software package coded with Matlab in order to simulate, analyze and fit the complex data measured at the synchrotron source was developed. The complete crystal structure of the 15.4 Å pentacene thin-film polymorph grown on four model types of gate dielectric materials, amorphous silicon dioxide (a−SiO2), octadecyltrichlorosilane-treated a−SiO2 (OTS), Topas (“thermoplastic olefin polymer of amorphous structure”) and polystyrene films, was solved. It was found, that the unit cell parameters are identical within measurement precision on all measured substrates. The crystal structure belongs to the space group P-1 and was found to be triclinic with the following lattice parameters: a = 5.958 ± 0.005 Å, b = 7.596 ± 0.008 Å, c = 15.61 ± 0.01 Å, alpha = 81.25 ± 0.04°, beta = 86.56 ± 0.04° and 2 gamma = 89.80 ± 0.10°. The unit cell volume V = 697 Å^3 is the largest of all pentacene polymorphs reported so far. However, the molecular arrangement within the unit cell was found to be substrate dependent. Here, the following parameters are reported: The herringbone angle is 54.3°, 55.8°, 59.4° and 55.1° for a−SiO2, OTS, Topas and polystyrene, respectively. The tilts of the two molecular axes (theta_A, theta_B) are (5.6°, 6.0°), (6.4°,6.8°), (5.6°, 6.3°) and (5.7°, 6.0°) for a−SiO2, OTS, Topas and polystyrene, respectively. To conclude, it was shown that the molecular orientation in the unit cell differs among substrates while the unit cell dimensions of the 15.4 Å pentacene polymorph are identical. This indicates that substrate effects have to be included if one aims on understanding the molecular structure of the thin-film phase in detail. The crystal structures reported here provide a basis to apply techniques such as density functional methods to investigate intrinsic charge transport properties and optical properties of organic thin film devices on a molecular level. In previous studies it was observed that different substrates vary the charge carrier mobility in OTFTs. The substrate dependent crystal structures observed here could be one reason for this variation. This topic may lead ultimatively to a controlled finetuning of intrinsic charge transport properties. The experimental approach to determine the crystal structure developed here can be easily applied to a wide range of organic thin film systems used in organic electronic devices.

Fakultät für Chemie und Pharmazie - Digitale Hochschulschriften der LMU - Teil 02/06
Hochdrucksynthese neuer SiO2-analoger Nitride des Phosphors sowie neue Verfahren zur Darstellung von Metallaziden

Fakultät für Chemie und Pharmazie - Digitale Hochschulschriften der LMU - Teil 02/06

Play Episode Listen Later Apr 17, 2007


Tue, 17 Apr 2007 12:00:00 +0100 https://edoc.ub.uni-muenchen.de/7767/ https://edoc.ub.uni-muenchen.de/7767/1/Karau_Friedrich.pdf Karau, Friedrich ddc:500, dd

neuer verfahren friedrich sowie ddc:500 sio2 zur darstellung phosphors ddc:540
Fakultät für Geowissenschaften - Digitale Hochschulschriften der LMU

Abstract The shear viscosity, density, thermal expansivity and specific heat capacity are important factors controlling the morphology, rheology, and texture of volcanic flows and deposits. These physical properties of silicate melts largely depend on chemical composition, water content, crystal content, bubble content and stress applied to the melt. Recently, it has been recognized that the applied stress plays an important role in the so called “glass transition” area of silicate melts. This kinetic boundary between brittle and ductile behavior affects the eruptive style. Thorough knowledge of the physical processes that occur at this brittle/ductile transition can affect the decision making of governments during volcanic crises and help to reduce and/or avoid loss of life and assets. Scientific knowledge from this research can be directly applied to the geomaterial industry. In addition, natural magmatic rocks are the major raw material in the production of microfibres and continuous fibres. Compared to normal glass fibres, rock fibres have a remarkable high temperature endurance, acid and alkali resistance and anti-heat impact. Rock products can be used as substitutes for metal and timber. They are likely to become more widely used in the near future. Further use for natural magmatic rocks include crushed stone, concrete aggregate, railroad ballast, production of high quality textile fibres, floor tiles, acid-resistant equipment for heavy industrial use, rockwool, basalt pipers, basalt reinforcement bars, basalt fibre roofing felt (ruberoid), basalt laminate (used as a protective coating), heat-insulating basalt fibre materials and glass wool (fibre glass). Since Bottinga and Weill (1970) first suggested that the density of melts in two or three component systems could be used to determine partial molar volumes of oxide components in silicate liquids, several models based upon this approach have been proposed in the Earth sciences literature. Considering that knowledge the densities of 8 Zn-bearing silicate melts have been determined, in equilibrium with air, in the temperature range of 1363 to 1850 K. The compositional joins investigated [sodium disilicate (NS2)- ZnO; anorthite-diopside 1 atm eutectic (AnDi)-ZnO; and diopside-petedunnite] were chosen based on the pre-existing experimental density data set, on their petrological relevance, and in order to provide a test for significant compositionally induced variations in the structural role of ZnO. The ZnO concentrations investigated range up to 25 mol% for sodium disilicate, 20 mol% for the anorthite-diopside 1 atm eutectic, and 25 mol% for petedunnite. Molar volumes and expansivities have been derived for all melts. The molar volumes of the liquids decrease with increasing ZnO content. The partial molar volume of ZnO derived from the volumetric measurements for each binary system is the same within error. A multicomponent fit to the volumetric data for all compositions yields a value of 13.59(0.55) cm3/mol at 1500 K. I find, no volumetric evidence for compositionally induced coordination number variations for ZnO in alkali-bearing vs. alkali-free silicate melts nor for Al-free vs. Al-bearing silicate melts. The partial molar volume of ZnO determined here may be incorporated into existing multicomponent models for the prediction of silicate melt volume. High temperature density determinations on ZnO-bearing silicate melts indicate that a single value for the partial molar volume of ZnO is sufficient to describe the volumetric properties of this component in silicate melts. The presence of alkalies and Al does not appear to influence the partial molar volume of ZnO within the temperature range investigated here. There is no volumetric evidence across this temperature range presented for composition to influence the coordination polyhedron of ZnO in silicate melts. The next physical property to be studied was thermal expansivity. Ten compositions from within the anorthite-wollastonite-gehlenite (An-Wo-Geh) compatibility triangle were investigated. Due to the lack of information about the thermal expansivities at supercooled liquid temperatures this study focused on the measurement of thermal expansivity using a combination of calorimetric and dilatometric methods. The volumes at room temperature were derived from densities measured using the Archimedean buoyancy method. For each sample density was measured at 298 K using glass that had a cooling-heating history of 10-10 K min-1. The thermal expansion coefficient of the glass from 298 K to the glass transition interval was measured by a dilatometer and the heat capacity was measured using a differential scanning calorimeter from 298 to 1135 K. The thermal expansion coefficient and the heat flow were determined at a heating rate of 10 K min-1 on glasses that were previously cooled at 10 K min-1. Supercooled liquid density, molar volume and molar thermal expansivities were indirectly determined by combining differential scanning calorimetric and dilatometric measurements assuming that the kinetics of enthalpy and shear relaxation are equivalent. The data obtained on the supercooled liquids were compared to high-temperature predictions from the models of Lange and Carmichael (1987), Courtial and Dingwell (1995) and Lange (1997). The best linear fit combines the supercooled liquid data presented in this study and the high temperature data calculated using the Courtial and Dingwell (1995) model. This dilatometric/calorimetric method of determining supercooled liquid molar thermal expansivity greatly increases the temperature range accessible for thermal expansion. It represents a substantial increase in precision and understanding of the thermodynamics of calcium aluminosilicate melts. This enhanced precision demonstrates clearly the temperature independence of the melt expansions in the An-Wo-Geh system. This contrasts strongly with observations for neighboring system such as Anorthite-Diopside and raises the question of the compositional/structural origins of the temperature dependence of thermal expansivity in multicomponent silicate melts. In addition, the partial molar volumes and the thermal expansivities of 10 samples from within the An-Wo-Geh compatibility triangle have been determined. They have been incorporated into existing multicomponent models in order to predict silicate melt volume. The resulting supercooled liquid volumes near glass transition temperatures (1135 - 1200 K) and at superliquidus temperature were combined to yield temperature independent thermal expansivities over the entire temperature range. In light of results presented in this study, together with the published data, it seems that binary and ternary systems have temperature independent thermal expansivities from the supercooled liquid to the superliquidus temperature at 1 atmosphere. By combining the high temperature densitometry data (i.e., above liquidus) from the literature with volume and expansivity data obtained at Tsc, a wide temperature range is covered. There is no volumetric evidence across this temperature range for temperature independent thermal expansivities in the An-Wo-Geh compatibility triangle. Furthemore, the thermal expansivities of three multicomponent glasses and liquids have been obtained over a large temperature interval (298 - 1803 K) which involved combining the results of low and high temperature measurements. The sample compositions investigated were derived from three natural lavas; Vesuvius 1631 eruption, Etna 1992 eruption and an Oligocene-Miocene lava flow from Slapany in the Bohemian massif. The original rocks are tephri-phonolite, trachybasalt and basanite, respectively. This is the first time this calorimetric/dilatometric method has ever been applied to natural magmatic melts. The low temperature volumes were derived from measurements of the glass density of each sample after cooling at 5 K.min-1 at 298 K, followed by measurements of the glass thermal expansion coefficient from 298 K to the samples´ respective glass transition interval. Supercooled liquid volumes and molar thermal expansivities were determined by combining scanning calorimetric and dilatometric measurements, assuming that the kinetics of enthalpy and shear relaxation are equivalent (Webb, 1992). High temperature densities were measured using Pt double bob Archimedean densitometry. In addition, the oxidation state of iron was analyzed using a wet chemistry method. Small amounts of samples were taken from the liquids using a “dip” technique at regular temperature steps during high temperature densitometry. The measured high temperature densities have been compared with predicted densities across the same temperature interval calculated using the multicomponent density models of Lange and Carmichael (1987) and Lange (1997). The resulting data for liquid volumes near glass transition temperatures (993 - 1010 K) and at super-liquidus temperatures (1512 - 1803 K) are combined to yield temperature dependant thermal expansivities over the entire supercooled and stable liquid range. These results confirm the observation of Knoche et al. (1992a); Knoche et al. (1992b); Toplis and Richet (2000); Liu and Lange (2001); Gottsmann and Dingwell (2002) of the temperature dependence of thermal expansivity. The molar volumes indicate, in general, a significant negative temperature dependence of the expansivity. The thermal molar expansivity of the glasses increase from SiO2-poor (basalt-basanite composition) to relatively SiO2-rich melts (tephri-phonolite composition). The thermal molar expansivity at supercooled liquid temperatures increases in the same manner as the glasses. In contrast, the thermal molar expansivity of the superliquidus liquid decrease from SiO2-poor to relatively SiO2-rich melts. Non-linear dependency of molar volume has been observed for all studied samples above the glass transition area. Molar volume from just above the glass transition area to about 1873 K can be predicted by a non-linear logarithmic curve. This study examined the expansivities and molar volumes of relatively basic compositions. Extending such a study to more SiO2-rich, but still geologically relevant, compositions remains a challenge, because the high viscosities of such melts preclude the use of immersion techniques. This problem can be solved using a high temperature densitometry where the volume is measured on levitated sample. I would like to urge studies of this sort in the future. Results from such studies should provide important information regarding a number of geological processes, which occur in such extremely high viscous liquids. A new viscosity measurement for melts spanning a wide range of anhydrous compositions including: rhyolite, trachyte, moldavite, andesite, latite, pantellerite, basalt and basanite are discussed in the last chapters. Micropenetration and concentric cylinder viscometry measurements cover a viscosity range of 10-1 to 1012 Pas and a temperature range from 973 to 1923 K. These new measurements, combined with other published data, provide a high-quality database comprising ~800 experimental data on 44 well -characterized melt compositions. This database is used to recalibrate the model proposed by Giordano and Dingwell [Giordano, D., Dingwell, D. B., 2003a. Non-Arrhenian multicomponent melt viscosity: a model. Earth Planet. Sci. Lett. 208, 337–349] for predicting the viscosity of natural silicate melts. The recalibration shows that: a) the viscosity (η)–temperature relationship of natural silicate liquids is very well represented by the VFT equation [log η=A+B/ (T−C)] over the full range of viscosity considered here, b) the use of a constant high-T limiting value of melt viscosity (e.g., A) is fully consistent with the experimental data. There are 3 different compositional suites (peralkaline, metaluminous and peraluminous) that exhibit different patterns in viscosity, the viscosity of metaluminous liquids is well described by a simple mathematical expression involving the compositional parameter (SM) but the compositional dependence of viscosity for peralkaline and peraluminous melts is not fully controlled by SM. For these extreme compositions we refitted the model using a temperature-dependent parameter based on the excess of alkalies relative to alumina (e.g., AE/SM). The recalibrated model reproduces the entire database to within 5% relative error. On the basis of this extended database the T-variation of the viscous response of strong and fragile liquids within a wide range of compositions shows three clearly contrasting compositional suites (peralkaline, metaluminous and peraluminous). As a result, I present an extended model to calculate the viscosity of silicate melts over a wide range of temperatures and compositions. This model constitutes a significant improvement with respect to the Giordano and Dingwell (2003a) study in that: 1) The number of experimental determinations over which the model is calibrated is larger. 2) The range of investigated compositions is larger. 3) The investigated temperature range is larger. 4) The assumption is made that at infinite temperature, the viscosity of silicate melts converges to a common, but unknown value of the pre-exponential factor (A=−4.07, Equation (7.1)). In particular the compositional range involves a large number of viscosity determinations for peralkaline and peraluminous compositions in a temperature interval between 949 and 2653 K. Furthermore, it is shown that the assumption of a common value of the pre-exponential parameter A produces an equally good representation of the experimental data as that produced by each melt having its own specific A-value. This optimization also induces a strong coupling between data sets that stabilizes the range of solutions and allows the different rheological behaviour of extreme compositions (peralkaline and peraluminous vs. metaluminous) to be discriminated. It was demonstrated that, although the parameter SM (Giordano and Dingwell, 2003a) can be used to model compositional controls on the viscosities of metaluminous liquids, it does not capture the viscosity of peralkaline and peraluminous liquids. The differences in the rheological behaviour of these extreme compositions reflect important differences in the structural configuration of metaluminous, peralkaline and peraluminous melts. Subsequently, a second regression of the experimental data was performed involving a second compositional parameter (AE) that accounts for the excess of alkali oxides over the alumina. Incorporating this temperature-dependent compositional parameter (i.e., AE) into the SM-based model (Equation 7.7) appears to account for the anomalous rheological behaviour of peralkaline and peraluminous liquids. The resulting model reproduces the entire experimental database to within an average RMSE of 0.45 log units. The model presented here is recommended for the estimation of the viscosity of anhydrous multicomponent silicate melts of volcanic interest.

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Non-linear properties of supercooled liquids in the system Na2O---SiO2

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Play Episode Listen Later Jan 1, 1994


The physical properties, viscosity, density, heat capacity and thermal expansivity, of relaxed supercooled liquids in the temperature range just above the glass transition have been determined for ten compositions along the compositional binary Na2O---SiO2, in the range of 2–45 mole% Na2O, by a combination of scanning calorimetry, dilatometry and micropenetration viscometry. The viscosity, density, heat capacity and thermal expansivity in the glassy state have also been determined. The heat capacities illustrate a linear composition dependence for the glassy state and a smooth but strongly non-linear composition dependence for the supercooled liquid state. The thermal expansivities were determined by dilatometry up to the glass transition and, by a normalized comparison of relaxation behavior in the glass transition interval, to temperatures 50°C above the glass transition. The expansivity is a linear function of the molar composition in the glass but a strongly non-linear function of molar composition in the supercooled liquid. The viscosity data just above the glass transition temperature, combined with data from high temperature using the concentric cylinder method, illustrate that the composition dependence of viscosity is strongly non-linear and exhibits an inflection as a function of composition. The glass transition temperature, taken as the peak temperature of the calorimetric measurements, is not in general an isokom in this system. The data for these property determinations in the Na2O---SiO2 system provide much improved constraints on the partial molar properties of SiO2 liquid and partial molar properties of the SiO2 component in silicate melts. The complex behavior of the transport properties, i.e. the glass transition temperature and the viscosity, point to complexities in viscous flow beyond that of simple binary mixing of the Na2O and SiO2 components.

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X-ray absorption study of Ti-bearing silicate glasses

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Play Episode Listen Later Jan 1, 1994


Ti K-edge XANES spectra have been collected on a series of Ti-bearing silicate glasses with metasilicate and tetrasilicate compositions. The intensity of the preedge feature in these spectra has been found to change with glass composition and varies from 29 to 58% (normalized intensity) suggesting a variation in structural environent around the absorbing atom. The pre-edge peak intensity increases for the alkali titanium tetrasilicate glasses from 35% to 58% in the order Li < Na < K < Rb, Cs whereas for the metasilicate compositions there is a maximum for the K-bearing glass. The pre-edge peak intensity remains constant for the alkaline earth titanium metasilicate glasses, Ca and Sr (34%) but increases slightly for Ba (41%). As the intensity of this feature is inversely correlated with coordination number, a comparison of the pre-edge intensity data for the investigated glasses with those of materials of known coordination number leads us to establish a regression equation and to infer that the average coordination number of Ti in these glasses ranges from 4.8 to 5.8. Large alkali cations appear to stabilize a relatively low average coordination number for Ti in silicate melts. The Ti structural environment results appear also to vary as a function of SiO2 content within the K2O-TiO2-SiO2 system. A number of physical properties of the melts from which these glasses were quenched and of other Ti-bearing silicate melts, have been determined in recent years. Clear evidence of a variable coordination number of Ti, consistent with the interpretation of the present XANES data is available from density measurements. These and other property determinations are compared with the present spectroscopic observations in an attempt to relate structure and properties in these melts which contain a major component with variable coordination number.

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Compressibility of titanosilicate melts

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Play Episode Listen Later Jan 1, 1994


The effect of composition on the relaxed adiabatic bulk modulus (K0) of a range of alkali- and alkaline earth-titanosilicate [X 2 n/n+ TiSiO5 (X=Li, Na, K, Rb, Cs, Ca, Sr, Ba)] melts has been investigated. The relaxed bulk moduli of these melts have been measured using ultrasonic interferometric methods at frequencies of 3, 5 and 7 MHz in the temperature range of 950 to 1600°C (0.02 Pa s < s < 5 Pa s). The bulk moduli of these melts decrease with increasing cation size from Li to Cs and Ca to Ba, and with increasing temperature. The bulk moduli of the Li-, Na-, Ca- and Ba-bearing metasilicate melts decrease with the addition of both TiO2 and SiO2 whereas those of the K-, Rb- and Cs-bearing melts increase. Linear fits to the bulk modulus versus volume fraction of TiO2 do not converge to a common compressibility of the TiO2 component, indicating that the structural role of TiO2 in these melts is dependent on the identity of the cation. This proposition is supported by a number of other property data for these and related melt compositions including heat capacity and density, as well as structural inferences from X-ray absorption spectroscopy (XANES). The compositional dependence of the compressibility of the TiO2 component in these melts explains the difficulty incurred in previous attempts to incorporate TiO2 in calculation schemes for melt compressibility. The empirical relationship KV-4/3 for isostructural materials has been used to evaluate the compressibility-related structural changes occurring in these melts. The alkali metasilicate and disilicate melts are isostructural, independent of the cation. The addition of Ti to the metasilicate composition (i.e. X2TiSiO5), however, results in a series of melts which are not isostructural. The alkaline-earth metasilicate and disilicate compositions are not isostructural, but the addition of Ti to the metasilicate compositions (i.e. XTiSiO5) would appear, on the basis of modulus-volume systematics, to result in the melts becoming isostructural with respect to compressibility.

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A volume temperature relationship for liquid GeO2 and some geophysically relevant derived parameters for network liquids

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Play Episode Listen Later Jan 1, 1993


The thermal expansivity of liquid GeO2 at temperatures just above the glass transition has been obtained using a combination of scanning calorimetry and dilatometry. The calorimetric and dilatometric curves of c p and dV/dT are normalized to the temperature derivative of fictive temperature versus temperature using the method of Webb et al. (1992). This normalization, based on the equivalence of relaxation parameters for volume and enthalpy, allows the completion of the dilatometric trace across the glass transition to yield liquid expansivity and volume. The values of liquid volume and expansivity obtained in this study are combined with high temperature densitometry determinations of the liquid volume of GeO2 by Sekiya et al. (1980) to yield a temperature-volume relation for GeO2 melt from 660 to 1400 °C. Liquid GeO2 shows a strongly temperature-dependent liquid molar expansivity, decreasing from 20.27 × 10–4 cm3 mol–1°C–1 to 1.97 × 10–4cm3 mol–1 °C–1 with increasing temperature. The coefficient of volume thermal expansion ( v ) decreases from 76.33 × 10–6 °C–1 to 2.46 × 10–6 °C–1 with increasing temperature. A qualitatively similar volume-temperature relationship, with v decreasing from 335 × 10–6 °C–1 to 33 × 10–6 °C–1 with increasing temperature, has been observed previously in liquid B2O3. The determination of the glass transition temperature, liquid volume, liquid and glassy expansivities and heat capacities in this study, combined with compressibility data for glassy and liquid GeO2 from the literature (Soga 1969; Kurkjian et al. 1972; Scarfe et al. 1987) allows the calculation of the Prigogine-Defay ratio (), c p -c v and the thermal Grüneisen parameter ( th) for GeO2. From available data on liquid SiO2 it is concluded that liquid GeO2 is not a good analog for the low pressure properties of liquid SiO2.

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Chemical diffusivity of boron in melts of haplogranitic composition

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Play Episode Listen Later Jan 1, 1993


Chemical diffusivities of B in synthetic melts of haplogranitic composition have been measured by the diffusion couple technique at 1 atm between 1200–1600°C. The compositional profiles were measured by ion microprobe and modelled using the Boltzmann-Matano formalism to retrieve compositionally dependent interdiffusion coefficients. At the experimental conditions, B2O3 is found to exchange primarily with SiO2 and the interdiffusion coefficient increases with increasing replacement of Si by B in the melt. No isotopic fractionation of boron was observed in the diffusion zone at the experimental conditions. The compositional dependence of diffusivity increases with decreasing temperature. The activation energy of diffusion (~70 kcal) is similar to that for viscous flow in melts of the same composition and is relatively insensitive to B content between 1–10 wt% B2O3 in the melt. However, the addition of the initial 1 wt% B2O3 to a haplogranitic melt appears to dramatically lower the activation energy for these processes from ~ 100 kCal to ~70 kCal. Thus, common geochemical concentrations of B may affect petrogenesis of granitic rocks by their influence on these transport properties. Some implications of these results for crystal growth and dissolution in B-bearing melts and boron isotopic variation of granitic melts have been discussed. If diffusion is the rate-limiting process, boron isotopic heterogeneity may be maintained in granitic melts at magmatic temperatures on time scales of millions of years on a millimeter scale. The influence of small amounts of B on transport properties may also contribute toward resolution of an enigma regarding emplacement mechanisms of peraluminous granites.

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Effects of F, B2O3 and P2O5 on the solubility of water in haplogranite melts compared to natural silicate melts

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Play Episode Listen Later Jan 1, 1993


The effects of F, B2O3 and P2O5 on the H2O solubility in a haplogranite liquid (36 wt. % SiO2, 39 wt. % NaAlSi3O8, 25 wt. % KAlSi3O8) have been determined at 0.5, 1, 2, and 3 kb and 800, 850, and 900°C. The H2O solubility increases with increasing F and B content of the melt. The H2O solubility increase in more important at high pressure (2 and 3 kb) than at low pressure (0.5 kb). At 2 kb and 800°C, the H2O solubility increases from 5.94 to 8.22 wt. % H2O with increasing F content in the melt from 0 to 4.55 wt. %, corresponding to a linear H2O solubility increase of 0.53 mol H2O/mol F. With addition of 4.35 wt. % B2O3, the H2O solubility increases up to 6.86 wt. % H2O at 2 kb and 800°C, corresponding to a linear increase of 1.05 mol H2O/mol B2O3. The results allow to define the individual effects of fluorine and boron on H2O solubility in haplogranitic melts with compositions close to that of H2O-saturated thermal minima (at 0.5–3 kb). Although P has a dramatic effect on the phase relations in the haplogranite system, its effect on the H2O solubility was found to be negligible in natural melt compositions. The concominant increase in H2O solubility and F can not be interpreted on the basis of the available spectroscopic data (existence of hydrated aluminofluoride complexes or not). In contrast, hydrated borates or more probably boroxol complexes have been demonstrated in B-bearing hydrous melts.

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Energetics of the Charge-Coupled Substitution Si4+ Na++ T3+ in the-Glasses NaTO2–SiO2 (T = Al, Fe, Ga, B)

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Play Episode Listen Later Jan 1, 1990


Heats of solution in molten 2PbO·B2O3 at 973 K are reported for glasses xNaT3+O2–(1 –x)SiO2 for T = Fe, Ga. These measurements, combined with previous data for T = Al, B, give a relative measure of the enthalpy of the charge-coupled substitution Si4+→ Na++ T3+. The heats of solution become more endothermic with increasing x for x→ 0.5 and exhibit a maximum near x= 0.5. This indicates an exothermic enthalpy for the substitution and an overall stabilization of the glasses. The degree to which the glasses are stabilized decreases in the order Al > Ga > Fe > B. On the basis of molecular orbital calculations, X-ray scattering, and Raman spectroscopy, it is argued that this trend is primarily due to a decrease in the range of energetically favorable T–O–T bond angles as Al, Ga, Fe, and B are substituted for Si.

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Structural relaxation in silicate melts and non-Newtonian melt rheology in geologic processes

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Play Episode Listen Later Jan 1, 1989


The timescale of structural relaxation in a silicate melt defines the transition from liquid (relaxed) to glassy (unrelaxed) behavior. Structural relaxation in silicate melts can be described by a relaxation time, , consistent with the observation that the timescales of both volume and shear relaxation are of the same order of magnitude. The onset of significantly unrelaxed behavior occurs 2 log10 units of time above . In the case of shear relaxation, the relaxation time can be quantified using the Maxwell relationship for a viscoelastic material; S = S/G (where S is the shear relaxation time, G is the shear modulus at infinite frequency and S is the zero frequency shear viscosity). The value of G known for SiO2 and several other silicate glasses. The shear modulus, G , and the bulk modulus, K , are similar in magnitude for every glass, with both moduli being relatively insensitive to changes in temperature and composition. In contrast, the shear viscosity of silicate melts ranges over at least ten orders of magnitude, with composition at fixed temperature, and with temperature at fixed composition. Therefore, relative to S, G may be considered a constant (independent of composition and temperature) and the value of S, the relaxation time, may be estimated directly for the large number of silicate melts for which the shear viscosity is known. For silicate melts, the relaxation times calculated from the Maxwell relationship agree well with available data for the onset of the frequency-dependence (dispersion) of acoustic velocities, the onset of non-Newtonian viscosities, the scan-rate dependence of the calorimetric glass transition, with the timescale of an oxygen diffusive jump and with the Si-O bond exchange frequency obtained from 29Si NMR studies. Using data obtained over a range of frequencies and strain-rates we illustrate the significance of relaxed versus unrelaxed behavior in laboratory experiments on silicate melts. Similarly, using strain-rate estimates for magmatic processes we evaluate the significance of the liquid-glass transition in igneous petrogenesis. Dedicated to the memory of Chris Scarfe

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Viscosities of melts in the Na2O---FeO---Fe2O3---SiO2 system and factors controlling relative viscosities of fully polymerized silicate melts

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Play Episode Listen Later Jan 1, 1988


Na2O---B2O3---SiO2 and Na2O-Ga2O3 viscosities decrease in the order aluminosilicate > ferrosilicate, (galliosilicate ?) > borosilicate. Thp electronegativities of the trivalent cations are inversely correlated with the relative viscosities of melts in these systems. Similarly, the electronegativities of network-stabilizing cations are inversely correlated with melt viscosity for alkali and alkaline-earth aluminosilicate melt systems. The variation in the viscosity of tectosilicate melts is correlated with estimated average T-O-T bond angles, and exothermic heats of solution of quench glasses. Structural controls of viscosity discussed are tetrahedral ordering and relative bond strengths. The acmite component in natural, peralkaline, silicic volcanics will not contribute directly to high melt viscosities for these lavas.

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Melt densities in the Na2O-FeO-Fe2O3-SiO2 system and the partial molar volume of tetrahedrally-coordinated ferric iron in silicate melts

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Play Episode Listen Later Jan 1, 1988


The densities of 12 melts in the Na2O-FeO-Fe2O3-SiO2 system have been determined in equilibrium with air, in the temperature range of 1000–1500°C, using the double bob, Archimedean technique. Ferrous iron determinations of 100–200 mg samples, “dip” quenched from high temperature, indicate that all the melts investigated were highly oxidized under these experimental conditions. 57Fe Mössbauer spectra of glasses obtained by drop quenching 80 mg melt samples from loop equilibration runs yield Fe3+/Fe2+ data equivalent to that for the densitometry (dip) samples for all but the most viscous melt, and confirm that all but one melt equilibrated with air during the densitometry measurements. Melt densities range from 2.17 to 2.88 g/cm3 with a mean standard deviation (from replicate experiments) of 0.36%. Least squares regression of the density data at 1300, 1400 and 1500°C, was calculated, both excluding and including excess volume terms (herein named linear and nonlinear fits, respectively) and the root mean squared deviation (RMSD) of each regression was compared with the total experimental error. The partial molar volumes computed for linear fits for Na2O and SiO2 are similar to those previously reported for melts in the Na2O-Al2O3-SiO2 system (Steinet al., 1986). The partial molar volumes of Fe2O3 obtained in these linear fits are equal to those obtained by Shiraishi et al. (1978) in the FeO-Fe2O3-SiO2 system but 5 to 10% lower than reported by Mo et al. (1982) in multicomponent melts. The partial molar volume exhibited by Fe3+ in this system is representative of the partial molar volume of tetrahedrally coordinated Fe3+ in silicate melts.

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Melt densities in the CaO-FeO-Fe2O3-SiO2 system and the compositional dependence of the partial molar volume of ferric iron in silicate melts

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Play Episode Listen Later Jan 1, 1988


The densities of 10 melts in the CaO-FeO-Fe2O3-SiO2 system were determined in equilibrium with air, in the temperature range of 1200 to 1550°C, using the double-bob Archimedean technique. Melt compositions range from 6 to 58 wt% SiO2, 14 to 76 wt% Fe2O3 and 10 to 46 wt% CaO. The ferric-ferrous ratios of glasses drop-quenched from loop fusion equilibration experiments were determined by 57Fe Mössbauer spectroscopy. Melt densities range from 2.689 to 3.618 gm/cm3 with a mean standard deviation from replicate experiments of 0.15%. Least-squares regressions of molar volume versus molar composition have been performed and the root mean squared deviation shows that a linear combination of partial molar volumes for the oxide components (CaO, FeO, Fe2O3 and SiO2) cannot describe the data set within experimental error. Instead, the inclusion of excess terms in CaFe3+ and CaSi (product terms using the oxides) is required to yield a fit that describes the experimental data within error. The nonlinear compositional-dependence of the molar volumes of melts in this system can be explained by structural considerations of the roles of Ca and Fe3+. The volume behavior of melts in this system is significantly different from that in the Na2O-FeO-Fe2O3-SiO2 system, consistent with the proposal that a proportion of Fe3+ in melts in the CaO-FeO-Fe2O3-SiO2 system is not tetrahedrally-coordinated by oxygen, which is supported by differences in 57Fe Mössbauer spectra of glasses. Specifically, this study confirms that the 57Fe Mössbauer spectra exhibit an area asymmetry and higher values of isomer shift of the ferric doublet that vary systematically with composition and temperature (this study; Dingwell and Virgo, 1987, 1988). These observations are consistent with a number of other lines of evidence (e.g., homogeneous redox equilibria, Dickenson and Hess, 1986; viscosity, Dingwell and Virgo, 1987,1988). Two species of ferric iron, varying in proportions with temperature, composition and redox state, are sufficient to describe the above observations. The presence of more than one coordination geometry for Fe3+ in low pressure silicate melts has several implications for igneous petrogenesis. The possible effects on compressibility, the pressure dependence of the redox ratio, and redox enthalpy are briefly noted.

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The effect of oxidation state on the viscosity of melts in the system Na2O-FeO-Fe2O3-SiO2

Geowissenschaften - Open Access LMU

Play Episode Listen Later Jan 1, 1987


The viscosities of two melts in the system Na2O-FeO-Fe2O3-SiO2 have been measured as a function of oxidation state. The experiments were conducted by concentric-cylinder viscometry, on melts equilibrated with gas mixtures in a vertical tube, gas-mixing furnace. Viscosity determinations were made during stepwise reduction and oxidation of the melts. 57Fe Mössbauer spectra were obtained on quenched melt samples recovered during the viscometry experiments. In addition, a series of loop fusion experiments were performed at calibrated ƒO2 values in order to relate viscosity determinations directly to ƒO2. The viscosities of acmite and NS4F40 (Na-rich and Si-poor relative to acmite) melts decrease with reduction of Fe in the melts, as nonlinear functions of , yielding a region of viscosity invariance at moderate to low values of (

Geowissenschaften - Open Access LMU
The effect of fluorine on viscosities in the system Na2O-Al2O3-SiO2: implications for phonolites, trachytes and rhyolites

Geowissenschaften - Open Access LMU

Play Episode Listen Later Jan 1, 1985


The effect of fluorine on melt viscosities of five compositions in the system Na2O-Al2O3- SiO2h as been investigateda t one atmospherea nd 1000-1600'Cb y concentric-cylinder viscometry. The compositions chosen were albite, jadeite and nepheline on the join NaAlOlSiO2 and two others of the join at 75 mole percent SiO2, one peralkaline and one peraluminous. All melt viscosities were independent of shear rate over two orders of magnitude, indicating Newtonian behavior. All viscosity-temperature relationships were Arrhenian within error. Fluorine reduces the viscosities and activation energies of all melts investigated. The viscosity-reducing power of fluorine increases with the SiO2 content of melts on the join NaAlO2-SiO2 and is a maximum at Na/Al (molar) = I for melts containing 75 mole percent SiO2. Fluorine and water have similar effects on aluminosilicate melt viscosities, probably due to depolymerization of these melts by replacement of Si-O-(Si, Al) bridges with Si-OH and Si-F bonds, respectively. Evidence from slag systems shows that fluorine also reduces the viscosity of depolymerized silicate melts. The viscous flow of phonolites, trachytes and rhyolites will be strongly afected by fluorine. It appears that fluorine contents of igneous rocks may be combined with water in calculation schemes for determining the viscosity of natural melts.

Geowissenschaften - Open Access LMU
Chemical diffusion of fluorine in melts in the system Na2OAl2O3SiO2

Geowissenschaften - Open Access LMU

Play Episode Listen Later Jan 1, 1985


The volatilization of fluorine from three melts in the system Na2OAl2O3SiO2 has been investigated at 1 atm pressure and 1200–1400°C. The melts chosen have base compositions corresponding to albite, jadeite and a peraluminous melt with 75 mole % SiO2. Melt spheres were suspended from platinum loops in a vertical tube furnace in a flow of oxygen gas, then quenched, sectioned and analysed by electron microprobe. The microprobe scans indicate that transport of fluorine to the melt-vapor interface is by binary, concentration-independent interdiffusion of fluorine and oxygen. FO interdiffusivity increases in the order albite < peraluminous < jadeite. There is no simple reciprocal relationship between FO interdiffusivity and melt viscosity. Comparison with data on high-pressure interdiffusivity of fluorine and oxygen in jadeite melt indicates that FO interdiffusivity increases with pressure from 0.001 to 10 kbar while the activation energy remains unchanged. Fluorine chemical diffusivity in albite melt is substantially lower than H2O chemical diffusivity in obsidian melts suggesting that different diffusive mechanisms are responsible for the transport of F and H2O in igneous melts. Fluorine diffuses in albite melt via an anionic exchange with oxygen whereas water probably diffuses in obsidian melt via an alkali exchange mechanism.

Geowissenschaften - Open Access LMU
The solubility of water in melts in the system SiO2-Al2O3-Na2O-K2O at 1 to 2 kbars

Geowissenschaften - Open Access LMU

Play Episode Listen Later Jan 1, 1984


Sun, 1 Jan 1984 12:00:00 +0100 http://epub.ub.uni-muenchen.de/5974/ http://epub.ub.uni-muenchen.de/5974/1/5974.pdf Dingwell, Donald B.; Harris, D.; Scarfe, Christopher M. Dingwell, Donald B.; Harris, D. und Scarfe, Christopher M. (1984): The solubility of water in melts in the system SiO2-Al2O3-Na2O-K2O at 1 to 2 kbars. In: Journal of Geology, Vol. 92: pp. 387-395. Geowis