Апрель 2024 г.

Российская наука и мир (по материалам зарубежной электронной прессы)

CONTENTS / ОГЛАВЛЕНИЕ


• New material can be used as a membrane in nuclear reactors
• Russia has a plan to "restore" its dominant position in the global launch market
• Tomsk Polytechnic University joins Russian project on irradiated graphite
• KL Deemed to be University and ISTP SB-RAS forge strategic partnership in ionospheric physics and space weather research
• In Russia's Far East, a new heavy-lift rocket blasts off into space after two aborted launches
• Will Russia benefit from climate change?
• Russia-India signs agreement to operate large research hub in New Delhi
• Scientists successfully merge implants with bio-tissues
• Un matériau bat le record de stockage pour les moteurs à hydrogène d'un facteur 4!
• TSU evaluates strength of blades produced by space 3D printer

Уральские химики создали новый материал для протонпроводящих разделительных мембран ядерных реакторов на основе станната бария с добавкой лютеция в качестве легирующей примеси. С помощью таких мембран можно отделять тяжелые радиоактивные изотопы водорода, которые выделяются при функционировании реактора. После этого чистые изотопы можно использовать в термоядерных реакциях, а тяжелые - утилизировать.

The new proton conductor developed by Ural scientists can be used as a separation membrane for hydrogen isotopes. This will make it possible to extract deuterium and tritium from the gas mixture and then use them for their intended purpose - either to recycle or to use. The scientists' development can be used in nuclear power plants (NPPs) to improve the efficiency of chemical separation. The scientists have published detailed information about the new conductor and its benefits in Ceramics International.
"Our material can be used as a functional material in nuclear energy. The fact is that during the operation of a nuclear reactor, a radioactive isotope of hydrogen, tritium, is released, which needs to be properly utilized. Our material can act as a membrane capable of electrochemically pumping the tritium out of the supplied gas mixture. This makes it possible to use the tritium as a fuel for fusion reactors, depending on the task", explains George Starostin, Junior Researcher at the Hydrogen Energy Research Laboratory of UrFU.
A separation membrane has been created to separate individual components and, in the case of proton-conducting membranes, to separate hydrogen isotopes. According to the scientists, a membrane made of the created material will make it possible to optimize the separation process and obtain pure isotopes that can be used in thermonuclear reactions.
"Normally, all proton-conducting materials have better conductivity for light hydrogen isotopes. However, we found that our material was more efficient at transporting heavy hydrogen-deuterium. Thus, our material may be promising for making separation membranes in a nuclear reactor; it is capable of electrochemically pumping out radioactive tritium from the supplied gas mixture", explains George Starostin.
A proton-conducting material based on barium stannate was obtained by classical solid-phase synthesis with the addition of lutetium as an impurity, which increased the conductivity of the starting material by a factor of five.
"Solid-phase synthesis is the process of creating materials by mixing solids and heating them to high temperatures, typically on the order of 1500°C. We believe that the material we have obtained also has prospects for use as a component of a high-temperature electrochemical sensor sensitive to hydrogen-containing compounds, including deuterium and tritium", says George Starostin.
The research was carried out by scientists from UrFU together with colleagues from the Institute of High-Temperature Electrochemistry of the Ural Branch of the Russian Academy of Sciences.
Additional information: According to the World Nuclear Association, operating nuclear power plants will generate 2545 terawatts of energy in 2022, or about 10 percent of the world's total energy production.
According to Statista, the largest number of NPPs (93) is concentrated in the United States. In second place is France with 56 operating NPPs, which is the largest number in Europe. The third place in the global ranking by the number of operating NPPs belongs to China (55) - an actively developing industry and a large population make nuclear energy very much in demand. Russia ranks fourth with 37 operating NPPs.

Роскосмос заявил о намерении «восстановить» положение России на мировом рынке космических запусков за счет обновления парка ракет-носителей, в том числе малой грузоподъемности, причем уже к 2028-2029 гг.

It has been a terrible decade for the Russian launch industry, which once led the world. The country's long-running workhorse, the Proton rocket, ran into reliability issues and will soon be retired. Russia's next-generation rocket, Angara, is fully expendable and still flying dummy payloads on test flights a decade after its debut. And the ever-reliable Soyuz vehicle lost access to lucrative Western markets.
Yet there has been a more fundamental, underlying disease pushing the once-vaunted Russian launch industry toward irrelevance. The country has largely relied on decades-old technology in a time of serious innovation within the launch industry. So what worked at the turn of the century to attract the launches of commercial satellites no longer does against the rising tide of competition from SpaceX, as well as other players in India and China.
Through the first quarter of this year, Russia has launched a total of five rockets, all variants of the Soyuz vehicle. SpaceX alone has launched 32 rockets. China, too, has launched nearly three times as many boosters as Russia.
However, Russia has a plan to reclaim the dominance it once held in the global launch industry. In a recent interview published on the Roscosmos website the chief of the Russian space corporation, Yuri Borisov, outlined the strategy by which the country will do so.
The first step, Borisov said, is to develop a partially reusable replacement for the Soyuz rocket, called Amur-CNG. The country's spaceflight enterprise is also working on "ultralight" boosters that will incorporate an element of reusability.
"I hope that by the 2028-2029 timeframe we will have a completely new fleet of space vehicles and will be able to restore our position in the global launch services market," Borisov said in the interview.
A miracle, Amur
Russia has previously discussed plans to develop the Amur rocket (the CNG refers to the propellant, liquified methane). The multi-engine vehicle looks somewhat similar to SpaceX's Falcon 9 rocket in that preliminary designs incorporated landing legs and grid fins to enable a powered first-stage landing.
The country's space industry first unveiled its Amur plans back in 2020, when officials said they were targeting a low price of just $22 million for a launch on Amur, which would be capable of delivering 10.5 tons to low-Earth orbit. Essentially, then, it would offer about half the carrying capacity of a Falcon 9 rocket for one-third of the price.
At the time, Roscosmos officials were targeting a 2026 debut for Amur. Had they been able to deliver such a capability, it would undoubtedly be an attractively priced offering. Alas, the year 2026 appears to be off the table now. Through his comments, Borisov indicated that Amur will not be ready before 2028 or 2029.
Since there has been almost a year-for-year slippage in that date since Amur's announcement in 2020, it seems likely that even this target late in the decade is unrealistic.
Ultra-light booster
Borisov also references the development of ultra-light boosters - an interesting comment given that the trend in the global launch industry has been away from small rockets toward medium- and heavy-lift boosters. Here's what Borisov had to say about the development of a small-lift rocket by Russia.
"Two to three years ago, the Foundation for Advanced Research began work on something like a startup, but the work was kept quiet since the planned booster is supposed to be innovative in terms of manufacturing technology, including new castings and composite materials," Borisov said. "Testing of experimental stages for the future booster took place that were in principle successful, showing that we're on the right design track. Now we're interested in engine manufacturing and firming up their specs."
This is likely in reference to the "SLK launch vehicle," which could carry approximately 400 kg to low-Earth orbit in reusable mode and 600 kg in fully expendable mode. This vehicle may include a folding-wing solution for gliding back through Earth's atmosphere.
As with the Amur vehicle, dates for this rocket's development should be treated with great skepticism. When the Kremlin-operated news service TASS reported on the SLK rocket in 2021, it had an inaugural launch date of 2024.
Ultra-heavy booster
Many Russian officials were among those skeptical about the development of the massive Starship rocket by SpaceX, particularly because its first stage relies on firing 33 Raptor engines during its ascent toward orbit.
Russia's space program, under the direction of revered rocket scientist Sergei Korolev, tried to do this with the super-heavy N1 rocket in the 1960s. Its first stage was powered by 30 NK-15 engines. Four launch attempts from 1969 to 1972 all ended in failure.
"The N1 was far ahead of its time, with its ambitious goals exceeding the technology level of its era," Borisov said. "One issue was control of multiple engines; existing systems couldn't handle synchronous control of so many engines, the main reason why N1 was a fiasco."
But now that Starship has been successful - during its second and third test flights, the first stage of the SpaceX rocket had nominal performance, with all Raptor engines firing as intended - Russia is considering an ultra-heavy booster.
"Like the N1, Amur-CNG will be powered by a multi-engine design," he said. "If successful, we hope to be able to transition the same design principles into an ultra-heavy booster. So we are working on the same trail blazed by Korolev."
This may all play well with a domestic audience in Russia, but let's be real. Russia's launch industry is a pariah in the West, and the country is likely a decade away from deploying a vehicle that might be competitive with the Falcon 9. Its plans for an ultra-heavy booster are completely fantastical.

Томский политехнический университет присоединился к проекту по экспериментальному определению радиационных характеристик облученного графита уран-графитовых реакторов. Объект исследования - первый энергоблок Ленинградской АЭС, выведенный из эксплуатации в 2018 г.

Tomsk Polytechnic University has joined Russia’s project on the experimental determination of the radiation characteristics of the irradiated graphite from uranium-graphite reactors. Unit 1 of the Leningrad NPP - a 1,000 MWe RBMK reactor now closed for decommissioning - is the subject of the research.
Leningrad in Sosnovy Bor (Leningrad Region), which began construction in - 1967, started operation in 1973. Currently Leningrad NPP has four units in operation - units 3&4 with RBMK-1000 reactors, as well units 5&6 with new VVER-1200 units (also known as Leningrad-II 1&2). Units 5&6 replaced units 1&2 with RBMK-1000 reactors, which were decommissioned in 2018 and 2020.
Earlier an agreement for R&D was signed between Rosatom’s Experimental & Demonstration Centre for the Decommissioning of Uranium-Graphite Reactors (ODTs UGR - Opitno-Demonstratsionni Tsentr vivoda iz expluatatsii Uran Grafitovikh Reaktorov) and nuclear utility Rosenergoatom. This envisaged implementation of R&D on the experimental determination of the radiation characteristics of the irradiated graphite, which was used as moderator in the RBMKs. Among the main characteristics to be determined are the isotope composition, specific activity, spatial distribution of radionuclides in the graphite stacks from the reactors.
Scientific organisations with experience in sampling and measuring the radiation characteristics of irradiated graphite are involved in carrying out this large-scale and interesting work," said Alexander Pavlyuk, acting head of ODTs UGR. "Tomsk Polytechnic University was involved as a co-executor. An agreement was concluded between the university and ODC UGR for research and development work on the development of methods for the experimental determination of the radiation characteristics of the irradiated graphite."
As part of the work, it is planned to adapt and improve the instrumentation and methodological base for the tasks of studying the peculiarities of the localisation of radionuclides in the graphite stacks of RBMK-1000 reactors.
Pavlyuk noted that Russia’s existing nuclear fleet includes 11 RBMK reactors at the Leningrad, Smolensk and Kursk NPPs. Such reactors "are distinguished by having the highest power, energy intensity of the core, thermal neutron flux values, and duration of the operating period," he said.
To date, four RBMKs have been closed down - Leningrad 1&2 and Kursk 1&2 Final shutdown involves work to prepare the reactor for decommissioning, including unloading nuclear fuel from the core and removing nuclear fuel and other nuclear materials from the site. Closure of all reactors of this type is planned to be completed by 2038. The Leningrad reactors are considered as an a pilot project for the decommissioning such reactors. However, to obtain a decommissioning licence, it is first necessary to determine the content of radionuclides in the graphite stacks, Pavlyuk explained.
Project participants plan to test methods previously developed for examining graphite stacks of uranium graphite reactors, and also improve them taking into account the specifics of the RBMK. Technicians as part of the scientific group plan to test the scanning devices and develop all the necessary methods and recommendations.
"Moreover, this work, as a pilot project, also involves analysing the applied approaches, methods, hardware and methodological base in order to universalise their use when planning and performing similar work at the remaining RBMK-1000 reactor plants and reactor plants of other types," Pavlyuk noted.
Employees from the Institute of Physics & Chemistry of the Russian Academy of Sciences, Prolog LLC, and Sibnuklon LLC were also involved in the work. The project will be carried out as part of the R&D programme to develop innovative technologies for NPP decommissioning. The contract is designed for two years. Previously, at Tomsk Polytechnic University a research and development centre for decommissioning was opened with the support of Rosatom fuel company TVEL and Moscow Lomonosov State University. The new structure is being developed within the framework of the Ministry of Education & Science’s Priority 2030 programme.

Институт солнечно-земной физики СО РАН и Образовательный фонд Конеру Лакшмайя (Виджаявада, Индия) заключили Меморандум о взаимопонимании. Стороны намерены сотрудничать прежде всего в области физики ионосферы и космической погоды.

KL Deemed to be University renowned for its academic excellence and research culture, has officially formalized a strategic partnership through a Memorandum of Understanding (MoU) with the Institute of Solar-Terrestrial Physics of the Siberian Branch of the Russian Academy of Sciences, located in Irkutsk, Russia.
This collaborative agreement signifies a significant milestone in encouraging scientific and academic cooperation, particularly in the domains of Ionospheric Physics and Space Weather. The primary objective of this partnership is to enhance ties between KL Deemed to be University and ISTP SB-RAS, facilitating joint scientific endeavors and technological advancements. The MoU encompasses various collaborative activities, including international cooperation in the exploration and use of outer space for peaceful purposes, exchange of GNSS data, research personnel, and joint participation in projects, research activities, educational activities, conferences, symposia, seminars, workshops, and other academic initiatives between the two institutes.
Speaking on the occasion, Dr. G. Pardha Saradhi Varma, Vice Chancellor, KL Deemed to be University, said that, "This collaboration marks a significant milestone for the University. It shows our commitment to promote global academic excellence, thereby propelling us towards discoveries. Through this MoU, we aim to strengthen our bonds with ISTP SB-RAS and embark on joint scientific endeavors and technological advancements. Together, we look forward to making meaningful contributions to the scientific community and advancing our understanding of the complex phenomena of the Ionospheric Physics and Space Weather."
Dr. Yury Yasyukevich from ISTP SB-RAS and Dr. D. Venkata Ratnam from KL Deemed to be University will jointly lead their teams, overseeing the implementation of collaborative projects and initiatives stemming from this mutually advantageous partnership. The Institute of Solar-Terrestrial Physics of the Siberian Branch of the Russian Academy of Sciences (ISTP SB-RAS) specializes in fundamental, exploratory, and applied research studies in physics within the fields of magnetosphere, ionosphere, and upper atmosphere.
KL Deemed to be University, nestled in Andhra Pradesh, India, is research driven University, renowned for its commitment to academic excellence, innovative research, and holistic development. It offers a wide array of undergraduate, postgraduate, and doctoral programs across various disciplines, including engineering, sciences, management, and the arts, designed to cater to the evolving demands of the global workforce. The university’s state-of-the-art facilities, experienced faculty, and a strong focus on industry-academia collaboration create an environment that nurtures creativity, critical thinking, and problem-solving skills.

С третьей попытки с космодрома Восточный все же удалось запустить тяжелую ракету-носитель «Ангара-5». Первые два запуска были автоматически остановлены в последнюю минуту из-за технических неполадок. Ракеты «Ангара» проходят этап летно-конструкторских испытаний и в будущем должны заменить используемые в настоящее время носители «Протон».

Russia on Thursday successfully test-launched a new heavy-lift rocket from its Far Eastern space complex, a lift-off that comes after two aborted attempts earlier this week.
The first attempt to launch the Angara-A5 rocket from the Vostochny spaceport on Tuesday was canceled about two minutes before the scheduled liftoff due to a failure of the pressurization system of the oxidizer tank in the central block of the rocket.
The second attempted launch Wednesday was also aborted by the automatic safety system, which registered a flaw in the engine start control mechanism, said Yuri Borisov, head of Russia's state-controlled space corporation Roscosmos. He added that the failure was most likely rooted in a programming error.
Thursday's launch is the fourth for the Angara-A5, a heavy-lift version of the new Angara family of rockets that has been developed to replace the Soviet-designed Proton rockets.
The previous three launches were carried out from the Plesetsk launchpad in northwestern Russia.
After the 1991 breakup of the Soviet Union, Russia leased the Baikonur Cosmodrome from Kazakhstan and continued to use it for most of its space launches. The agreement with Kazakhstan allows Russia to keep leasing Baikonur for $115 million a year through 2050.
While Roscosmos has continued to rely on Baikonur, Russian authorities have developed Vostochny as the facility of choice for Angara launches. The construction of the new spaceport has dragged on for longer than planned and it has seen only limited use so far.
The development of the Angara-A-5, which is set to be the main launch vehicle for Russia's prospective lunar research program, has also faced repeated delays and dragged on years behind schedule.
Like the Soviet-designed Proton it's set to replace, the new rocket is intended to launch intelligence and communication satellites to geostationary orbits.

Проблема глобального изменения климата затрагивает Россию в полной мере - ее территория теплеет в несколько раз быстрее остальной планеты. Результаты этого уже ощущаются - таяние вечной мерзлоты с последующими наводнениями, оползнями и обвалами грунта, периоды сильной жары, засухи, лесные пожары. Международная сеть ученых PONARS представила результаты исследования, в котором попыталась оценить влияние климатических изменений на Россию и ее готовность к этому влиянию и его последствиям.

"There’s a narrative out there about climate change that says there are winners and losers. Even if most of the planet might lose from the changing climate, certain industries and countries stand to benefit. And Russia is usually at the tip of people’s tongues, with Russian officials even making the claim that Russia is a potential winner."
This portrayal comes from Debra Javeline, associate professor of political science at the University of Notre Dame and lead author of the new study in WIREs Climate Change. Her 16 coauthors - all Russia specialists and members of the Program on New Approaches to Research and Security in Eurasia (PONARS), a multinational cohort of academics from North America, Europe, and post-soviet Eurasia - debated this take.
The PONARS scholars, including Susanne Wengle, also an associate professor of political science at Notre Dame, studied the effects of climate change on Russia and Russia’s role in global efforts to combat climate change or obstruct climate action.
"We asked ourselves," Javeline says of her research team, "does Russia stand to benefit from climate change? Are the claims made by the Russian government officials accurate in that it does benefit them?"
The PONARS network includes social scientists of different disciplinary backgrounds, allowing each coauthor to contribute analysis of Russia in their respective fields, including agriculture, international affairs, the changing Arctic, public health, civil society, and governance.
Drawing on their collective expertise and a comprehensive literature review, the researchers found that Russia is already suffering from a variety of climate change impacts - despite the government’s positive spin and is ill-prepared to mitigate or adapt to those climate impacts. And, as the rest of the world transitions to renewable energy sources, Russia’s fossil-fuel-dependent government is not willing or ready to make alternative plans for the country, changes that could potentially benefit the whole of their society.
The cause for concern lies in the fact that not only is Russia considered the world’s largest country, occupying more than half the Arctic Ocean coastline, but it is also warming four times faster than Earth as a whole and is a primary emitter of greenhouse gases, according to the PONARS study.
Environmental impacts already occurring in Russia include flooding, heat waves, drought, and wildfires that affect not only communities, but agriculture, forestry, and water resources as well.
"Russia is one of the world’s most important producers and exporters of grains," says Wengle, an expert on Russian agriculture. "What this means is that the effects of climate change on Russian farms are a concern not only for Russians, but for everyone concerned with global markets for commodity crops and global food security."
Global warming has had a huge influence on Russia’s permafrost, which is now thawing at alarming rates. What was once considered permanently frozen, stable ground is now defrosting, shifting, and causing tremendous damage. The study points to increased flooding, landslides, caving, or sinking of ground that supports existing infrastructures - resulting in cracked foundations and compromised shelters.
"Some Russian cities in high-latitude regions report infrastructure damage from thawing permafrost and soil instability for up to 80% of buildings and for pipelines," the researchers discovered.
Russian leadership, however, interprets these climate impacts self-servingly and encourages its citizens to accept them as benefits, according to the PONARS scholars. For example, while Russian scientists warn about extreme temperatures and decreased Arctic sea ice, the Russian government touts a year-round Arctic sea route and a more livable climate overall. And although Russian climatologists study the effect of climate change, there are limited policies in place to reduce the vulnerability of some regions to climate impacts, and generally little adaptation planning and even less implementation of actual adaptations.
The researchers found that there is also a real climate leadership deficit in Russia and an absence of commitment to mitigate and adapt.
"No top political leader champions a climate agenda," they proclaim. "Those in the highest positions of power demonstrate silence or denial."
The PONARS study serves as a framework to identify gaps in research. In particular, the scientists believe that more research is needed on the political dimensions of Russia in our changing climate - namely, taking a closer look at the country’s centralized political system and how it handles policy challenges related to climate change.
Javeline and Wengle add that the researchers hope to improve understanding of climate issues affecting Russia so that when Russian leadership does decide to acknowledge the country’s precarious position in a changing climate, there will be a reliable base of knowledge to assist them with efforts to mitigate and adapt.

11-13 апреля в Нью-Дели прошел первый Индийско-российский образовательный саммит, во время которого Высшая школа экономики и Делийский университет заключили соглашение о стратегическом сотрудничестве. Помимо прочего, в рамках договора на территории Делийского университета будет открыт совместный научно-исследовательский центр.

The Higher School of Economics, located in Russia, and the University of Delhi signed an agreement on strategic cooperation and joint actions, and a large research hub will begin operating at the partner university here.
New Delhi hosted the Indo-Russian Education Summit last week, becoming the largest event of its kind in the history of India-Russia bilateral relations, according to the Russian embassy in India. About 60 Russian universities arrived in the national capital from Moscow, Saint Petersburg, Siberia, Crimea, the Urals and other regions.
"During the three-day educational forum, the Higher School of Economics (HSE) and the University of Delhi entered into an agreement on strategic cooperation and joint actions. As part of it, a large research hub will start operating at the partner university from India," the embassy stated in their statement.
HSE University is a national research university located in Moscow, Russia.
The summit held from April 11 to 13, was organized by the Russian State Agency under the Ministry of Foreign Affairs 'Rossotrudnichestvo' that specializes in humanitarian projects abroad as well as the Russian House in New Delhi and the Russian Embassy in India.
The summit brought together rectors of Indian and Russian universities, diplomats, politicians, scientists, and businessmen to explore new opportunities for cooperation in education, science and innovative technologies as well as professional training.
"At the plenary session on April 11, Deputy Head of Rossotrudnichestvo Pavel Shevtsov noted that the Summit provides leading Indian and Russian universities with an unprecedented platform to engage in transformative dialogue and exchange," the statement read.
The programme of the forum included three panel discussions, including, "Russia - India - BRICS: Role of Higher Education in the Development of Comprehensive Cooperation", "Career Opportunities for Indian Graduates of Russian Universities and Business as a Customer for the Training of Indian Personnel in Russia", "Cooperation between Russia and India in the Field of Medical Education" - and a round table themed "Technical Universities".
Later on the second day of the summit, a fair of Russian universities opened at the Le Meridien Hotel.
The exhibition stands were crowded with people, including, school children and students occupied the entire space of the hotel's huge assembly hall. The counters of Russian universities were attended by a huge number of journalists and representatives of educational institutions at.
The exhibition was aimed at introducing the youth for obtaining higher education in Russia as they have great interest in Russia's technical achievements, particularly, in space exploration, aviation and military technology, medicine.
"On the sidelines of the event, official and informal meetings of representatives of the Russian and Indian educational communities took place," according to the statement.
Moreover, Pavel Shevtsov and Russian Deputy Education Minister Denis Gribov visited the Sancta Maria International School in Faridabad. In New Delhi, they met with Secretary of the Education minister Sanjay Kumar. Meanwhile, a delegation from Moscow led by Russian Deputy Health Tatyana Semenova called on the leadership of the National Medical Commission (NMC). Furthermore, apart from the mentioned document, about a dozen similar agreements were signed as well.

В Томском государственном университете разработали универсальный метод адаптации свойств имплантационных материалов к биологическим тканям человека, чтобы избежать отторжения. Кроме того, ученые составили систему классификации материалов и тканей, чтобы упростить работу материаловедов и хирургов.

The main challenge reconstruction surgeons face when using current materials for tissue defects treatment is implant rejection, which can further complicate the lives of people impacted by physical trauma. Tomsk State University scientists developed a universally valid method for adjusting implants' properties to a person's biological tissues. Concurrently, they compiled a classification system for materials and tissues to streamline the work of materials scientists and surgeons.
"When choosing the right implant, a surgeon has to rely on their professional, yet subjective, experience", Ekaterina Marchenko, head of the TSU Laboratory of Superelastic Biointerfaces, explains. "Even when we have a high-quality biocompatible material, we still have to decide how to insert it and make sure it does not damage the adjacent tissues. When using fine wire mesh reinforcement, there is a chance it will not provide the necessary compression and fail to fixate an implant; a thicker one could cause perforation of adjacent tissues, inflammation, and rejection."
TSU scientists set the goal to create a method for fusing the living and the human-made, and the task has proven to be complicated. When working with metallic materials, it is vital to consider the many facets of classical mechanics, which include the laws of plasticity, elasticity, and so on.
"We know how to define the human-made materials," shares Ekaterina Marchenko. "We also know how to define tissues rheology-wise as well as in consideration to how they interact with fluids. But which criteria should we rely on when fusing the human-made and the living? Which parameters can we use to define these in a uniform manner given that they are completely different in nature?"
When solving the task, the team resorted to modeling: Through modeling, scientists found out how they can assess the biomechanical make-up of materials that have different structures and similar behavior. The new approach helped categorize a wide array of materials and tissues.
"Now we know for sure which parameters to pick each time," Ekaterina Marchenko continues. "For example, we know that muscles would need a wire mesh that is 60 micrometers thick, whereas skin would need 45 micrometers of thickness. The method has proven its effectiveness after conducting tests on laboratory animals. It is currently being adopted by Tomsk surgeons."
It was already used for treating a person with an extensive facial tissue defect. During treatment, doctors from the Tomsk National Research Medical Center of the Russian Academy of Sciences used a metallic fabric construction made at TSU. It helped preserve the facial tissues' flexibility and restore the person's quality of life. This was the first time a surgery like that was carried out in Russia.
The next step is accrediting the technique for it to be used nationwide. That way it can be used for systematizing medical materials and constructions produced not only at TSU, but in other Russia-based materials science facilities as well. Subsequently, surgeons and implant manufacturers will use the accumulated information. Knowing the specific properties will reduce implant installation risks and speed up the recovery process.
For reference:
TSU Laboratory of Superelastic Biointerfaces was established under a megagrant of the Government of the Russian Federation. Headed by Alexey Volynsky a professional in biotechnology with background in the University of South Florida, USA, the laboratory's scope of work includes fundamental and applied research, development of cutting-edge biocompatible materials for treating soft and hard tissues damaged as a result of a physical trauma, acquired disease, or congenital pathology.

Одна из основных проблем использования водорода в энергетике и транспорте - найти безопасный способ хранить это вещество. В газообразной форме водород легко утекает и взрывается, а хранение его в сжатом или сжиженном виде энергозатратно. Более подходящий вариант «упаковки» - сплавы, например, магниевые или циркониевые, способные удерживать водород в пустотах между атомами металлов, образующими кристаллическую решетку, и быстро выделять его обратно при нагреве. В таких сплавах на один атом металла приходится примерно два атома водорода. Международная же команда исследователей из России, Китая, Японии и Италии синтезировала два соединения, гептагидрид цезия (CsH₇) и нонагидрид рубидия (RbH₉), способных удерживать до 9 атомов водорода на один атом металла.

L'une des voies explorées pour décarboner les transports et l'industrie suppose de pouvoir stocker efficacement et sans danger de l'hydrogène. On envisage pour cela des matériaux solides et c'est la course dans les laboratoires mondiaux pour trouver celui qui sera le meilleur, le moins cher et le plus facile à produire. Une équipe internationale, menée notamment par le célèbre physicien et cristallographe russe Artem Oganov, vient d'accomplir quelques progrès en ce sens.
Futura suit depuis plus d'une décennie les travaux du physicien, chimiste et cristallographe russe Artem Oganov, dont le nom revient assez souvent sur le devant de la scène de la physico-chimie des matériaux à haute pression. Rappelons que ses travaux l'ont conduit dans plusieurs centres de recherche mondiaux de grande réputation, de l'université d'État de Moscou jusqu'à l'université Stony Brook en passant par l'University College London et l'ETH à Zurich.
De retour en Russie et après avoir été membre un temps du mythique Institut de physique et de technologie de Moscou (MIPT pour Moscow Institute of Physics and Technology, Московский физико-технический институт, en russe), il poursuit son exploration de la physique du solide dans le cadre du Skolkovo Institute of Science and Technology (Skoltech) que l'on peut considérer comme l'équivalent russe du Massachusetts Institute of Technology (MIT) aux États-Unis.
Il a contribué également à la mise en place du prix « ВЫЗОВ », une sorte de version moderne du prix Nobel et dont une partie est accessible à tous les chercheurs et ingénieurs de la noosphère sur la base de contributions de valeur en science et ingénierie uniquement.
Justement, Artem Oganov vient de publier avec ses collègues de Skoltech, de l'Institut de cristallographie Shubnikov de la Russian Academy of Sciences (RAS) et de centres de recherche en Chine, au Japon et en Italie, un nouvel article dans Advanced Energy Materials.
Il est notamment expliqué que cette équipe internationale a vérifié des prédictions théoriques basées sur l'algorithme nommé Uspex (Universal Structure Predictor : Evolutionary Xtallography, en russe uspekh signifie « succès »). Développé initialement par Artem Oganov, Uspex est utilisé par plus de 7 000 chercheurs dans le monde car il permet de prédire et d'explorer victorieusement la structure cristalline que vont adopter les atomes formant un matériau d'une composition chimique initiale donnée dans des conditions de pression et de température arbitraires, en particulier des conditions physiques difficiles à réaliser en laboratoire, comme celles des hautes pressions à l'intérieur des planètes géantes de glace du Système solaire telles Uranus et Neptune.
Le stockage de l'hydrogène, une clé de la décarbonation des transports et de l'industrie
Mais cette fois-ci, il s'agit d'une avancée de la connaissance et de la technologie bien terrestre puisque les chercheurs annoncent qu'ils ont découvert un matériau de stockage chimique de l'hydrogène capable d'« absorber » quatre fois plus de ce gaz difficile à contenir que les meilleurs prétendants actuels.
Rappelons qu'aucune étude sérieuse ne permet de penser que nous pourrons nous passer de l’énergie nucléaire dans les décennies à venir, bien au contraire. Mais il est tout aussi certain que les énergies renouvelables vont également monter en puissance et qu'en appoint de l'atome, il faudra trouver des moyens aussi efficaces et peu onéreux que possible pour stocker l'énergie électrique produite par intermittence par les éoliennes et les panneaux solaires.
L'hydrogène apparaît comme un moyen intéressant de stocker de l'énergie électrique mais, bien évidemment, ce n'est pas aussi simple que l'on pourrait le croire. On sait produire de l'hydrogène par électrolyse, mais cela veut dire qu'il y a un rendement pour cette conversion. La question se reposera avec la reconversion de l'hydrogène en électricité, par exemple avec une pile à combustible.
On comprend facilement qu'il faudrait donc, autant que possible, pouvoir utiliser directement de l'électricité car, en fait, un facteur de rendement devra être appliqué deux fois. Imaginons que ce facteur soit de 0,5 alors in fine, seul un quart de l'énergie initialement produite par du solaire ou de l'éolien sera utilisable si on la stocke.
La question est encore plus problématique si on veut faire du stockage à haute densité car il faut alors, par exemple, compresser voire liquéfier l'hydrogène, ce qui est aussi très énergivore.
Des hydrures métalliques pour stocker l'hydrogène
L'idée de stocker l'hydrogène directement sous forme solide dans un matériau qui l'absorbe est donc à considérer. C'est d'autant plus vrai qu'il faut trouver un moyen de stockage qui soit aussi peu dangereux que possible - sous forme de gaz, l'hydrogène peut facilement donner des explosions. Dans l'idéal, il faut un matériau aussi absorbant que possible, peu cher, facile à fabriquer et qui puisse libérer facilement et rapidement l'hydrogène qu'il contient principalement dans le cas des véhicules, que ce soit des voitures, des avions ou des transports en commun. L’hydrogène devrait donc jouer un rôle majeur dans la future économie à faibles émissions de carbone.
Parmi les voies de recherche à ce sujet, il y a donc aujourd'hui celle qu'explique dans le communiqué de Skoltech accompagnant la publication scientifique un autre des principaux auteurs de l'étude, Dmitrii Semenok.
« Certains matériaux, par exemple les alliages magnésium et zirconium peuvent stocker de l'hydrogène dans les vides entre les atomes métalliques qui composent la structure cristalline. De tels accumulateurs assurent un stockage relativement dense et sûr et libèrent de l'hydrogène assez rapidement à la demande s'ils sont chauffés. Mais s'il est possible de modifier les alliages métalliques en fonction des conditions requises pour la capture et la libération de l'hydrogène et du nombre de cycles de charge-décharge qu'ils supportent, il existe une limite relativement stricte à la quantité d'hydrogène qu'il est possible d'introduire dans ces matériaux : environ deux atomes d'hydrogène pour un atome de métal. »
Les composés que nous avons synthétisés - l'heptahydrure de césium CsH₇ et le nonahydrure de rubidium RbH₉ - contiennent respectivement jusqu'à sept et neuf atomes d'hydrogène par atome de métal. Et nous nous attendons à ce qu'ils soient les premiers matériaux riches en hydrogène stables à la pression atmosphérique, bien que ce dernier nécessite une confirmation. Quoi qu'il en soit, la proportion d'atomes d'hydrogène dans ces composés est la plus élevée parmi tous les hydrures connus, deux fois plus élevée que dans le méthane CH₄ ».
Des expériences relevant de la physique des hautes pressions
Artem Oganov précise également dans le communiqué comment lui et ses collègues ont obtenu ces matériaux prometteurs. « Nous faisons réagir de la poudre d'ammoniac-borane riche en hydrogène avec du césium ou du rubidium. Cela produit des sels appelés amiboranes de césium ou de rubidium. La chaleur décompose ces sels en monohydrures de césium ou de rubidium et en beaucoup d'hydrogène. Comme l'expérience se déroule dans une cellule entre deux diamants exerçant 100 000 fois la pression atmosphérique, l'hydrogène supplémentaire est forcé dans les vides du réseau cristallin, formant de l'heptahydrure de césium et du nonahydrure de rubidium - ce dernier, dans deux variétés distinctes de réseau cristallin. »
Le communiqué de Skoltech se conclut en expliquant que « l'équipe compte désormais répéter l'expérience en utilisant des presses hydrauliques à grande échelle à une pression plus faible - environ 10 000 atmosphères - pour obtenir de plus grandes quantités de polyhydrures de césium et de rubidium et vérifier qu'une fois synthétisés, ces composés restent stables même à pression atmosphérique, contrairement aux autres polyhydrures connus à ce jour ».

В Томском государственном университете изучат физико-механические характеристики образцов, напечатанных на 3D-принтере на Международной космической станции, и сравнят их с земными. Предположительно, космические образцы будут качественнее, так как в условиях отсутствия гравитации материалы для 3D-печати распределяются более равномерно.

According to Tomsk State University (TSU), test cosmonaut, Oleg Artemyev, has presented a dozen samples of blades to TSU that were created on the International Space Station (ISS) using the first Russian space 3D printer, which TSU scientists contributed to the development of, for mechanical testing. The samples have undergone strength testing at the TSU Research Institute of Applied Mathematics and Mechanics, and the researchers will compare them with the same blades printed on Earth.
Oleg Artemyev presented the space blades to Tomsk Region Governor, Vladimir Mazur, during their meeting at VDNKh, in Moscow, where a pavilion of the Tomsk Region was opened as part of the Russia International Exhibition and Forum. When the Governor returned to Tomsk, he presented the blades to TSU.
Such blades are standard for studying the strength and other properties of composite products created on 3D printers and then used in science with new materials.
"The new shift of ISS cosmonauts has printed more than just samples, which were previously gifted to the experiment participants but now their physical and mechanical characteristics will be studied. Using special equipment, we will test them for strength by tearing them in the thin part and monitoring under what loads this happens," said Alexander Vorozhtsov, Vice-Rector for Research and Innovation at TSU.
Furthermore, scientists will compare the blades printed in space with blades printed on Earth. Specialists assume that the space samples will be of higher quality because the materials for 3D printing are distributed more evenly in the absence of gravity.
RSC Energia, TSU, and TPU scientists and engineers participated in creating the Russian first space 3D printer for manufacturing parts and tools aboard the ISS. The work was carried out as part of developing the scientific, technical, and educational potential of universities and academic institutions of the Tomsk Region to solve issues of the ISS long-term program.
The 3D printing experiment is dedicated to developing polymer materials products using 3D technologies in space. In the future, these technologies will enable cosmonauts on near-Earth orbital stations to create necessary parts and tools directly in space, without waiting for their delivery from Earth.
The 3D printer was delivered to the ISS for experiments in June 2022. In early fall, the first Russian crew members tested it aboard the station, printing 19 various samples, including the logo of Tomsk State University.
Oleg Artemyev visited TSU and several divisions of the university in February 2023. As a result of the visit, Artemyev proposed that TSU material scientists create equipment that would help to produce strong refractory materials onboard the ISS for the repair and recovery work that the station sometimes requires. TSU researchers have accepted the proposal and, if necessary, the university’s technical faculties’ scientists will be involved.

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