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News Article | May 3, 2017
Site: www.materialstoday.com

Russian researchers believe that they have solved the mystery of why fullerite nanocomposites are so ultrahard [Kvashnina et al., Carbon 115 (2017) 546]. Nearly 20 years ago, a team of scientists at the Technological Institute for Superhard and Novel Carbon Materials led by Vladimir Blank synthesized a material based on polymerized fullerite with outstanding stiffness and hardness called ‘tisnumit’. Fullerite is a molecular crystal lattice made up of fullerene molecules – hollow spheres of carbon atoms. But the atomic structure of fullerite and the origin of its exceptional mechanical properties remained a mystery. Now a team of researchers from the same institute, along with colleagues from Moscow Institute of Physics and Technology, Skolkovo Institute of Science and Technology, Emanuel Institute of Biochemical Physics, and the National University of Science and Technology, has come up with a new model of fullerite, which closely matches experimental data. The researchers suggest that when the fullerite is compressed at high temperature, some of the fullerenes transform into polycrystalline diamond while the rest remains in a compressed state (SH-phase). “The amorphous structure of ultrahard fullerite led us to assume that the compressed polymerized fullerite is surrounded by an amorphous shell made of carbon atoms with diamond-like sp3 bonds, which does not allow the structure to expand,” explains researcher Alexander G. Kvashnin. In other words, fullerite could be considered as a grain of nanocomposite with a shell of diamond. The fullerite grains are arranged in a period pattern in single crystal diamond like raisins in a cake, says Kvashnin. “It is known from the experiments and theory, that a material in a compressed state will display greater mechanical properties compared to relaxed state,” he explains. “In this nanocomposite with nanoparticles in the SH-phase clamped in a diamond-like amorphous matrix, the improved mechanical properties remain preserved.” Those mechanical properties include ultrahigh mechanical stiffness, higher even than that of diamond. If such outstanding properties could be realized in materials that could be readily synthesized, it could lead to mechanical parts with reduced wear and longer lifetimes in many industries. But such ultrahigh hard materials, which are likely to require high pressures to produce, could be difficult to handle. Kvashnin believes the next step forward is to try to synthesize the new material under different high pressure and temperature conditions and investigate its properties. Researchers around the world are looking anew at ultrahard carbon and Kvashnin hopes their new model will help understand these exceptional materials.

News Article | February 15, 2017
Site: phys.org

But all bets are off, if the students journey to the center of the Earth, à la Jules Verne's Otto Lidenbrock or if they venture to one of the solar system's large planets, such as Jupiter or Saturn. "That's because extremely high pressure, like that found at the Earth's core or giant neighbors, completely alters helium's chemistry," says Boldyrev, faculty member in USU's Department of Chemistry and Biochemistry. It's a surprising finding, he says, because, on Earth, helium is a chemically inert and unreactive compound that eschews connections with other elements and compounds. The first of the noble gases, helium features an extremely stable, closed-shell electronic configuration, leaving no openings for connections. Further, Boldyrev's colleagues confirmed computationally and experimentally that sodium, never an earthly comrade to helium, readily bonds with the standoffish gas under high pressure to form the curious Na He compound. These findings were so unexpected, Boldyrev says, that he and colleagues struggled for more than two years to convince science reviewers and editors to publish their results. Persistence paid off. Boldyrev and his doctoral student Ivan Popov, as members of an international research group led by Artem Oganov of Stony Brook University, published the pioneering findings in the Feb. 6, 2017, issue of Nature Chemistry. Additional authors on the paper include researchers from China's Nankai University, Center for High Pressure Science and Technology, Chinese Academy of Sciences, Northwestern Polytechnical University, Xi'an and Nanjing University; Russia's Skolkovo Institute of Science and Technology, Moscow Institute of Physics and Technology, Sobolev Institute of Geology and Mineralogy and RUDN University; the Carnegie Institution of Washington, Lawrence Livermore National Laboratory, Italy's University of Milan, the University of Chicago and Germany's Aachen University and Photo Science DESY. Boldyrev and Popov's role in the project was to interpret a chemical bonding in the computational model developed by Oganov and the experimental results generated by Carnegie's Alexander Goncharov. Initially, the Na He compound was found to consist of Na cubes, of which half were occupied by helium atoms and half were empty. "Yet, when we performed chemical bonding analysis of these structures, we found each 'empty' cube actually contained an eight-center, two-electron bond," Boldyrev says. "This bond is what's responsible for the stability of this enchanting compound." Their findings advanced the research to another step. "As we explore the structure of this compound, we're deciphering how this bond occurs and we predicted that, adding oxygen, we could create a similar compound," Popov says. Such knowledge raises big questions about chemistry and how elements behave beyond the world we know. Questions, Boldyrev says, Earth's inhabitants need to keep in mind as they consider long-term space travel. "With the recent discovery of multiple exoplanets, we're reminded of the vastness of the universe," he says. "Our understanding of chemistry has to change and expand beyond the confines of our own planet." Explore further: Scientists discover extraordinary compounds that may be hidden inside Jupiter and Neptune More information: A stable compound of helium and sodium at high pressure, Nature Chemistry, DOI: 10.1038/nchem.2716

Agency: European Commission | Branch: H2020 | Program: RIA | Phase: EO-3-2015 | Award Amount: 2.60M | Year: 2016

Two trends have recently emerged in space systems and could even further strengthen in the future: small satellites, with the development of key modularisation and miniaturisation technologies, and the deployment of constellations and distributed networks of satellites. It is of primordial importance for Europe to properly analyse those trends and determine whether or not they could provide a competitive advantage for Earth Observation (EO) systems. To address those challenges, Operational Network of Individual Observation Nodes, (ONION) investigates the distribution of spacecraft functionalities into multiple cooperating nodes, leveraging on the emerging fractionated and federated satellite system concepts. The proposed concept provides augmentation, supplementation, and possibilities of new mission for future EO Missions (for science and commercial applications). ONION objectives: 1. Review the emerging fractionated and federated observation system concepts 2. Identify potential benefits to be obtained in light of observation needs in different Earth Observation domains 3. Identify key required technology challenges entailed by the emerging fractionated and federated satellite system concepts, to be faced in Horizon 2021-2027 4. Validate observation needs with the respective user communities to be fit for purpose in terms of scientific and commercial applications 5: To propose an overall strategy and technical guidelines to implement such concepts at Horizon 2021-2027 ONION will confirm the feasibility of the first established concepts to respond to the identified needs through use-cases. The baseline of the concept consists to supplementing current mission profiles with missing observation bands, augmenting mission lifetimes, and ultimately sharing the capabilities across multiple spacecraft platforms. ONION will enable mission designers and implementers to decide which fractionated and federated concepts will provide competitive imaging from space.

Agency: European Commission | Branch: H2020 | Program: RIA | Phase: PROTEC-1-2014 | Award Amount: 2.36M | Year: 2015

The smooth functioning of the European economy and the welfare of its citizens depends upon an ever-growing set of services and facilities that are reliant on space and ground based infrastructure. Examples include communications (radio, TV, mobile phones), navigation of aircraft and private transport via GPS, and service industries (e.g. banking). These services, however, can be adversely affected by the space weather hazards. The forecasting of space weather hazards, driven by the dynamical processes originating on the sun, is critical to the mitigation of their negative effects. This proposal brings world leading groups in the fields of space physics and systems science in order to develop an accurate and reliable forecast system for space weather. It combines their individual strengths to significantly improve the current modelling capabilities within Europe and to produce a set of forecast tools to accurately predict the occurrence and severity of space weather events. Within project PROGRESS we will develop an European tool to forecast the solar wind parameters just upstream of the Earths magnetosphere. We will develop a comprehensive set of forecasting tools for geomagnetic indices. We will combine the most accurate data based forecast of electron fluxes at GEO with the most comprehensive physics based model of the radiation belts currently available to deliver a reliable forecast of radiation environment in the radiation belts. This project will deliver these individual forecast tools together with a unified tool that combines the forecasting tools with the prediction of the solar wind parameters at L1 to substantially increase the lead-time of space weather forecasts.

News Article | November 29, 2016
Site: www.eurekalert.org

Scientists from the Lomonosov Moscow State University in cooperation with colleagues have worked out a safe, not that expensive and highly efficient method, which allows to speed up and improve searching of new germicides. They have elaborated a system, which measures antimicrobial activity, along with determining the mode of action of a new material. The research results are published in a top-rated journal Antimicrobial Agents and Chemotherapy. The research has been conducted in collaboration with colleagues from the Moscow Institute of Physics and Technology, the Skolkovo Institute of Science and Technology and Gause Institute of New Antibiotics. Bacteria constantly become resistant to antibiotics, what compels mankind to search for new materials, which could solve this problem, over the last decades. The main search method is high throughput screening -- namely testing of a huge number of materials from chemical libraries, as well as of new natural compounds. However, such experiments don't provide with any data regarding the mode of action. In order to improve technique efficiency it's necessary to search for ways of decreasing reagent costs, process automation and the reduction of this activity stages number. There are already strains of a wide range, which help in identification of the activity of different antibiotic types. Combination of these strains could provide a benefit by accelerating the search process of necessary compounds and operating principle understanding. However, this requires plenty of each material testing. So, scientists face a dilemma: whether to simultaneously test many materials according to one characteristic or many characteristics of one material in order to understand, which impact it has. Both ways aren't perfect, however, Russian scientists have made an attempt to make a compromise by combination of these two approaches' advantages. Ilya Osterman, Doctor of Chemical Sciences, a researcher of the Chemistry of Natural Compounds Department, at the Faculty of Chemistry of the Lomonosov Moscow State University, who is the research author, informs: "We've worked out an approach, which allows to in vivo determine not only the mode of action of new promising antimicrobial agents, but also their efficiency. Approach automation has allowed to analyze thousands of compounds per day". The created reporter system (a term, used in molecular biology, in order to describe reporter gene or markers, inserted into an organism, which help to measure, how actively other genes work) is based on genes, which code two fluorescent proteins. One of them is a far-red protein Katushka2S, which is a marker for a termination of translation -- namely, protein synthesis. Its light could be seen in case protein production terminates cause of a stop of ribosome movement along the RNA chain. Upstream Katushka2S protein gene there was inserted a regulatory component of a tryptophan operon, which contains in its genome instructions of tryptophan amino acid biosynthesis. An operon is a functional group of genes, one part of which codes proteins, providing some work together. The other part regulates the number of these proteins, intensifying of suppressing their synthesis, when required. A tryptophan operon contains an attenuator -- a genome portion, where in case of tryptophan excess, transcription stops. Genes of tryptophan biosynthesis were replaced with a Katushka2S protein gene. The attenuator itself was also changed: namely, an alanine codon was inserted instead of a three letter codon of a tryptophan amino acid in the structure of the coded enzymes. This modified attenuator stopped reacting to tryptophan concentration, however, it became dependant on antibiotics, which disrupt protein synthesis -- in their presence the amount of Katushka2S protein gets large. Ilya Osterman shares: "At the first stage there was elaborated a gene engineering design, which included two fluorescent proteins. First protein expression depended on the presence of protein synthesis inhibitors, while expression of the second one -- on the presence of DNA synthesis inhibitors. Afterwards, with the help of a hyperresponsive strain of coliform bacteria there was created a reporter, aimed at the detection of corresponding antibiotic types". What was the second fluorescent protein? It turned out to be RFP - a red fluorescent protein. It's interesting that color also matters: both protein shine in the same range (of red and far-red), which is allowed to pass through human tissues quite well. A RFP gene was inserted in such a way that it started working during SOS-response -- namely, cell reaction to stress, uncomfortable conditions, which require alertness from DNA damage and repair system. According to the scientists' idea, this process should start the synthesis of a red fluorescent protein, which, like warning red light, could give a notice that there is something wrong inside a bacterium cell. The more light there is, the stronger effect an antibiotic has. How one should assemble such a reporter system? Scientists have put a RFP gen right after the sulA gen promoter, namely the area, where the main organoid of protein synthesis -- a ribosome, -- moving along the chain, gets learnt the sequence start, where protein is recorded. SulA gen starts at the last stages of SOS-response and suppresses cell division. So, once sulA gen starts operating, a red fluorescent protein also begins synthesizing in conjunction with it. Katushka2S operated in the same way in a tryptophan operon, it only warned with the help of red light with different wave length about a termination of protein synthesis and not DNA synthesis. This system of two reporters has already been tested on activity clarification of a new antibiotic -- amicoumacin, -- along with some other antibiotics. The target, which amicoumacin hits, has been unknown before. The leading author of the research further notices: "So far, with the help of this approach we've analyzed more than 50 thousands of compounds, discovered new inhibitors of protein and DNA synthesis, which could become the basis of new germicides in the future. The process of screening will be continued".

News Article | January 7, 2016
Site: www.materialstoday.com

A team of scientists from the US Department of Energy's (DOE) Argonne National Laboratory, Northwestern University and Stony Brook University has, for the first time, created a two-dimensional sheet of boron – a material known as borophene. Scientists are interested in two-dimensional materials because of their unique characteristics, particularly involving their electronic properties. Borophene is an unusual material because it shows many metallic properties at the nanoscale even though three-dimensional, or bulk, boron is nonmetallic and semiconducting. Because borophene is both metallic and atomically thin, it holds promise for possible applications ranging from electronics to photovoltaics, said Argonne nanoscientist Nathan Guisinger, who led the experiment. "No bulk form of elemental boron has this metal-like behavior," he said. A paper describing this study is published in Science. Like its neighbor in the periodic table, carbon, which appears in nature in forms ranging from humble graphite to precious diamond, boron wears a number of different faces, called allotropes. But that's where the similarities end. While graphite is composed of stacks of two-dimensional sheets that can be peeled off one at a time to produce one-atom-thick graphene, there is no such analogous process for making two-dimensional boron. "Borophenes are extremely intriguing because they are quite different from previously studied two-dimensional materials," Guisinger said. "And because they don't appear in nature, the challenge involved designing an experiment to produce them synthetically in our lab." Although at least 16 bulk allotropes of boron are known, scientists had never before been able to make a whole sheet, or monolayer, of borophene. "It's only in the recent past that researchers have been able to make tiny bits of boron at the nanoscale," said Andrew Mannix, a Northwestern graduate student and first author of the study. "This is a brand new material with exciting properties that we are just beginning to investigate." "Boron has a rich and storied history and a very complicated chemistry," added Mark Hersam, professor of materials science and engineering at Northwestern's McCormick School of Engineering and Applied Science, who helped advise Mannix. "This is something that could have easily not worked, but Andy had the courage and persistence to make it happen." One of boron's most unusual features comprises its atomic configuration at the nanoscale. While other two-dimensional materials look more or less perfectly smooth at the nanoscale, borophene looks like corrugated cardboard, buckling up and down depending on how the boron atoms bind to one another. The ‘ridges’ of this cardboard-like structure produce a material phenomenon known as anisotropy, in which a material's mechanical or electronic properties – like its electrical conductivity – become directionally dependent. "This extreme anisotropy is rare in two-dimensional materials and has not been seen before in a two-dimensional metal," Mannix said. Based on theoretical predictions of borophene's characteristics, the researchers also noticed that it likely has a higher tensile strength, meaning the ability to resist breaking when pulled apart, than any other known material. "Other two-dimensional materials have been known to have high tensile strength, but this could be the strongest material we've found yet," Guisinger said. The discovery and synthesis of borophene was aided by computer simulation work led by Stony Brook researchers Xiang-Feng Zhou and Artem Oganov, who is currently affiliated with the Moscow Institute of Physics and Technology and the Skolkovo Institute of Science and Technology. Oganov and Zhou used advanced simulation methods that showed the formation of the crinkles on the corrugated surface. "Sometimes experimentalists find a material and they ask us to solve the structure, and sometimes we do predictions first and the experiment validates what we find," Oganov said. "The two go hand-in-hand, and in this international collaboration we had a bit of both." "The connection we have between the institutions allows us to achieve things that we couldn't do alone," Hersam added. "We needed to combine scanning tunneling microscopy with X-ray photoelectron spectroscopy and transmission electron microscopy to both obtain a view of the surface of the material and verify its atomic-scale thickness and chemical properties." As they grew the borophene monolayer, the researchers discovered another advantage with their experimental technique. Unlike previous experiments that used highly toxic gases in the production of nanoscale boron-based materials, this experiment involved a non-toxic technique called electron-beam evaporation. This involves vaporizing a source material and then condensing a thin film on a substrate – in this case, boron on silver. "When we did our theoretical work, I had doubts as to the feasibility of obtaining two-dimensional boron because boron likes to form clusters, and ironing it out into two-dimensions I thought would be challenging," Oganov said. "It turned out that growing on the substrate was key, because the boron and silver turn out not to react with each other." This story is adapted from material from Northwestern University, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.

News Article | December 1, 2015
Site: phys.org

The technique could lead to high-quality 3-D cameras built into cellphones, and perhaps to the ability to snap a photo of an object and then use a 3-D printer to produce a replica. Further out, the work could also abet the development of driverless cars. "Today, they can miniaturize 3-D cameras to fit on cellphones," says Achuta Kadambi, an MIT graduate student in media arts and sciences and one of the system's developers. "But they make compromises to the 3-D sensing, leading to very coarse recovery of geometry. That's a natural application for polarization, because you can still use a low-quality sensor, and adding a polarizing filter gives you something that's better than many machine-shop laser scanners." The researchers describe the new system, which they call Polarized 3D, in a paper they're presenting at the International Conference on Computer Vision in December. Kadambi is the first author, and he's joined by his thesis advisor, Ramesh Raskar, associate professor of media arts and sciences in the MIT Media Lab; Boxin Shi, who was a postdoc in Raskar's group and is now a research fellow at the Rapid-Rich Object Search Lab; and Vage Taamazyan, a master's student at the Skolkovo Institute of Science and Technology in Russia, which MIT helped found in 2011. When polarized light gets the bounce If an electromagnetic wave can be thought of as an undulating squiggle, polarization refers to the squiggle's orientation. It could be undulating up and down, or side to side, or somewhere in-between. Polarization also affects the way in which light bounces off of physical objects. If light strikes an object squarely, much of it will be absorbed, but whatever reflects back will have the same mix of polarizations that the incoming light did. At wider angles of reflection, however, light within a certain range of polarizations is more likely to be reflected. This is why polarized sunglasses are good at cutting out glare: Light from the sun bouncing off asphalt or water at a low angle features an unusually heavy concentration of light with a particular polarization. So the polarization of reflected light carries information about the geometry of the objects it has struck. This relationship has been known for centuries, but it's been hard to do anything with it, because of a fundamental ambiguity about polarized light. Light with a particular polarization, reflecting off of a surface with a particular orientation and passing through a polarizing lens is indistinguishable from light with the opposite polarization, reflecting off of a surface with the opposite orientation. This means that for any surface in a visual scene, measurements based on polarized light offer two equally plausible hypotheses about its orientation. Canvassing all the possible combinations of either of the two orientations of every surface, in order to identify the one that makes the most sense geometrically, is a prohibitively time-consuming computation. To resolve this ambiguity, the Media Lab researchers use coarse depth estimates provided by some other method, such as the time a light signal takes to reflect off of an object and return to its source. Even with this added information, calculating surface orientation from measurements of polarized light is complicated, but it can be done in real-time by a graphics processing unit, the type of special-purpose graphics chip found in most video game consoles. The researchers' experimental setup consisted of a Microsoft Kinect—which gauges depth using reflection time—with an ordinary polarizing photographic lens placed in front of its camera. In each experiment, the researchers took three photos of an object, rotating the polarizing filter each time, and their algorithms compared the light intensities of the resulting images. On its own, at a distance of several meters, the Kinect can resolve physical features as small as a centimeter or so across. But with the addition of the polarization information, the researchers' system could resolve features in the range of hundreds of micrometers, or one-thousandth the size. For comparison, the researchers also imaged several of their test objects with a high-precision laser scanner, which requires that the object be inserted into the scanner bed. Polarized 3D still offered the higher resolution. A mechanically rotated polarization filter would probably be impractical in a cellphone camera, but grids of tiny polarization filters that can overlay individual pixels in a light sensor are commercially available. Capturing three pixels' worth of light for each image pixel would reduce a cellphone camera's resolution, but no more than the color filters that existing cameras already use. The new paper also offers the tantalizing prospect that polarization systems could aid the development of self-driving cars. Today's experimental self-driving cars are, in fact, highly reliable under normal illumination conditions, but their vision algorithms go haywire in rain, snow, or fog. That's because water particles in the air scatter light in unpredictable ways, making it much harder to interpret. The MIT researchers show that in some very simple test cases—which have nonetheless bedeviled conventional computer vision algorithms—their system can exploit information contained in interfering waves of light to handle scattering. "Mitigating scattering in controlled scenes is a small step," Kadambi says. "But that's something that I think will be a cool open problem." Explore further: Research duo develop a means for people to conceptualize polarized light

News Article | August 22, 2016
Site: news.mit.edu

Duane Boning has been named the Clarence J. LeBel Professor of Electrical Engineering. The chair is named for Clarence Joseph LeBel '26, SM '27, who co-founded Audio Devices in 1937, and was a pioneer in recording discs, magnetic media for tapes, and in hearing aids and stethoscopes. “Boning’s teaching is recognized as outstanding at both the undergraduate and graduate levels, and he is a leader in the field of manufacturing and design,” said Anantha Chandrakasan, the Vannevar Bush Professor of Electrical Engineering and head of the Department of Electrical Engineering and Computer Science (EECS). “This is fitting recognition of his outstanding contributions to research, teaching, mentoring, and service.” Boning’s research focuses on manufacturing and design, with emphasis on statistical modeling, control, and variation reduction in semiconductor, MEMS, photonic, and nanomanufacturing processes. His early work developed computer integrated manufacturing approaches for flexible design of IC fabrication processes. He also drove the development and adoption of run-by-run, sensor-based, and real-time model-based control methods in the semiconductor industry. He is a leader in the characterization and modeling of spatial variation in IC and nanofabrication processes, including plasma etch and chemical-mechanical polishing (CMP), where test mask design and modeling tools developed in his group have been commercialized and adopted in industry. Boning served as editor in chief for the IEEE Transactions on Semiconductor Manufacturing from 2001 to 2011, and was named a fellow of the IEEE for contributions to modeling and control in semiconductor manufacturing in 2005. In addition to creating the graduate-level course 6.780J/2.830J (Control of Manufacturing Process), he has lectured in several core EECS subjects, including 6.003 (Signals and Systems) and 6.001 (Structure and Interpretation of Computer Programs), and is also an outstanding recitation and laboratory instructor. His teaching has been recognized with the MIT Ruth and Joel Spira Teaching Award. Boning won the Best Advisor Award from the MIT ACM/IEEE student organization in 2012 and the 2016 Capers and Marion McDonald Award for Excellence in Mentoring and Advising in the School of Engineering. Boning served as associate head from Electrical Engineering in EECS from 2004 to 2011. He has previously and presently serves as associate director in the Microsystems Technology Laboratories, where he oversees the information technology and computer-aided design services organization in the laboratories. He is a long-standing and active participant in the MIT Leaders for Global Operations program. Since 2011, he has served as the director for the MIT/Masdar Institute Cooperative Program, fostering many joint activities between MIT and Masdar Institute. From 2011 through 2013, he served as founding faculty lead in the MIT Skoltech Initiative, working to launch the Skolkovo Institute of Science and Technology (Skoltech). Within MIT, Boning has served on several Institute committees, including as chair of the Committee on Undergraduate Admissions and Financial Aid (CUAFA) in 2007, and he will serve as chair of the Committee on the Undergraduate Program (CUP) in 2016-2017.

Zhugayevych A.,Los Alamos National Laboratory | Zhugayevych A.,Skolkovo Institute of Science and Technology | Tretiak S.,Los Alamos National Laboratory
Annual Review of Physical Chemistry | Year: 2015

We review recent progress in the modeling of organic solar cells and photovoltaic materials, as well as discuss the underlying theoretical methods with an emphasis on dynamical electronic processes occurring in organic semiconductors. The key feature of the latter is a strong electron-phonon interaction, making the evolution of electronic and structural degrees of freedom inseparable. We discuss commonly used approaches for first-principles modeling of this evolution, focusing on a multiscale framework based on the Holstein-Peierls Hamiltonian solved via polaron transformation. A challenge for both theoretical and experimental investigations of organic solar cells is the complex multiscale morphology of these devices. Nevertheless, predictive modeling of photovoltaic materials and devices is attainable and is rapidly developing, as reviewed here. © 2015 by Annual Reviews. All rights reserved.

News Article | September 7, 2016
Site: www.techtimes.com

Using a computer model, researchers from the Moscow Institute of Physics and Technology and the Skolkovo Institute of Science and Technology discovered which molecules may be hiding deep within Uranus and Neptune. Artem Oganov and Gabriele Saleh found that, at high pressures, which is common for the planets' interiors, extraordinary polymeric and molecular compounds like carbonic and orthocarbonic acid are formed. Their findings were released in Scientific Reports. According to the researchers, Uranus and Neptune are mostly made up of oxygen, hydrogen and carbon. And under atmospheric pressure, all the compounds of oxygen, hydrogen and carbon are thermodynamically unstable, save for carbon dioxide, water and methane. Carbon dioxide and water will have no trouble remaining stable when the pressure increases, but once beyond 93 gigapascals is reached, methane starts decomposing, forming heavy hydrocarbons like polyethylene, butane and ethane. For context, the pressure at the bottom of the deepest portion of the world's deepest oceans, the Mariana Trench, is 108.6 megapascals. This is about a thousand times lower than the pressures the researchers used for their study. With another team, Oganov had previously developed a powerful, most universal algorithm for predicting crystal structures and compounds called the Universal Structure Predictor: Evolutionary Xtallography. This algorithm has been used by other researchers to discover stable substances at high pressures and "forbidden" in classical chemistry, like salt variants previously unknown and exotic new aluminum, silicon and magnesium oxides. Now, Oganov and Saleh used the same algorithm to specifically observe the chemical behavior of oxygen-hydrogen-carbon systems under high pressure. They say the system is important because the entirety of organic chemistry is based on oxygen, hydrogen and carbon. "And until now it had not been entirely clear how they behave under extreme pressures and temperatures," added Oganov. The researchers took it upon themselves to uncover all compounds stable at up to 400 gigapascals and saw a handful of new substances, like a clathrate of molecular hydrogen, as well as methane 2CH4:3H2. At 0.95 gigapascals, they found that carbonic acid is thermodynamically stable, which is highly unusual as the substance is extremely unstable under normal environments. For starters, it requires strong acids for synthesis and can exist only at very low temperatures in a vacuum. At 44 gigapascals, carbonic acid turns into a polymer that stays stable under a minimum of 400 gigapascals of pressure. At 314 gigapascals, carbonic acid enters an exothermic reaction with water, producing orthocarbonic acid, which is also known as "Hitler's Acid" for it has a molecular structure resembling a swastika. Given these conditions, the researchers deduced that it's possible for Uranus and Neptune to feature cores with significant levels of carbonic and orthocarbonic acid. © 2016 Tech Times, All rights reserved. Do not reproduce without permission.

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