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2006 г.
Российская наука и мир
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январь февраль март апрель май июнь июль август сентябрь октябрь ноябрь декабрь
    В Дубне, в Объединенном институте ядерных исследований, поставлен уникальный эксперимент, в результате которого впервые химическим путем удалось доказать существование элемента 112 периодической таблицы Менделеева, что подтверждает также существование элементов 114 и 116. Несколько лет назад в той же Дубне, а затем в Германии удалось в физических экпериментах получить по 1-2 ядра сверхтяжелых элементов 114 и 116. Но открытие будет признано, если его удастся доказать независимым путем, лучше всего - в химической реакции, где время жизни атомов достаточно велико.

Voilà plusieurs décennies qu'un petit groupe de chevaliers chercheurs est en quête d'un Graal scientifique prédit par les théoriciens : celui d'un monde peuplé d'atomes qui n'existent pas sur Terre à l'état naturel. Tout récemment, révèlent les Izvestia, des physiciens russes de Dubna ont, sous la conduite de l'académicien Iouri Oganessian, créé un de ces atomes, un isotope de l'élément 114, qui a disparu une demi-seconde plus tard par décroissance radioactive.
Malgré l'aspect bien éphémère de cette découverte, la communauté des spécialistes a salué l'exploit en attendant de reproduire l'expérience pour la valider. Depuis la seconde guerre mondiale, les physiciens des grands pays engagés dans la course à la maîtrise de l'atome n'ont eu de cesse de produire artificiellement des éléments plus lourds que l'uranium, dont les différentes espèces (isotopes) ont un noyau qui contient 92 protons. C'est ce chiffre caractérisé par la lettre Z qui sert de carte d'identité aux atomes de tout poil. Le plus léger, l'hydrogène, occupant avec Z = 1 la première place du tableau périodique des éléments de Mendeleïev et le plus lourd, l'uranium, avec Z = 92, la dernière.
Comme ce que veulent les physiciens, les forces de la nature souvent le veulent aussi, d'autres éléments plus lourds que l'uranium ont été rapidement produits pendant les années de guerre comme le neptunium (93) ou le plutonium (94). Au fil du temps, la liste s'est allongée avec la production d'éléments plus lourds encore mais à l'existence - les physiciens parlent de demi-vie - plus fugace : quelques fractions de seconde. On est ainsi passé du chiffre 92 de l'uranium à celui, 109, du meitnerium, isolé en 1982.
114 PROTONS
Mais il est une course plus haletante encore que mènent depuis les équipes russe de Dubna, américaines de Berkeley et de Livermore, allemande de Darmstadt et plus récemment japonaise de Riken et française de Ganil à Caen. En une dizaine d'années, les découvertes des atomes superlourds - c'est leur nom - 111, 112, 113, 114, 115, 116 et 118 ont été annoncées. Le dernier a été refusé pour falsification des résultats, et l'existence de certains d'entre eux demande à être reconfirmée avant qu'ils ne reçoivent définitivement un patronyme.
La tache est difficile. D'abord parce qu'il s'agit d'une physique délicate où l'on projette à très grande vitesse des atomes lourds sur des cibles d'atomes qui le sont également, ce qui génère durant une semaine des milliards de milliards d'événements dont un seul ou deux ont un intérêt. Ensuite, et c'est le cas de la dernière découverte de Dubna, parce que l'élément 114 qui vient d'être créé n'est pas le même que celui, 114 aussi, synthétisé par la même équipe en 1999. Il s'agit en fait d'un isotope - une sorte de "frère" - dont le noyau possède le même nombre de protons mais un nombre différent de neutrons.
Qu'importe, c'est quand même un pas de plus vers ce que tous cherchent : un élément dont la légende, ou plutot la théorie, prévoit l'existence et qui, parce que le nombre des protons et des neutrons de son noyau serait doublement magique, pourrait survivre pendant quelques heures.

© Le Monde.fr.
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    Математики из Новосибирска (Институт математики) и Красноярска (Институт вычислительного моделирования) способны заранее точно рассчитать места на побережье, куда могут обрушиться самые опасные волны цунами. Финансирует работу Федеральное агентство по науке и инновациям Министерства образования и науки РФ и Фонд гражданских исследований и разработок США. В проекте также участвует Тихоокеанская лаборатория охраны окружающей среды.

Mathematicians from Novosibirsk and Krasnoyarsk, working on a joint project with American colleagues (sponsored by the CRDF and the Federal Agency for Science and Innovations (Rosnauka) have improved the tsunami forecasting system.
To this end, they applied the method of the so-called circulation of tsunami data obtained in a real-time mode. This newest method is based on the latest results achieved by researchers in the theory and numerical algorithms of inverse problem solution.
A tsunami, which means "a wave in a harbor" in Japanese, is a grandiose sight with disastrous effects. It can be caused by the underwater earthquake and a volcano's work, or even by falling of a large landslip or a huge piece of ice. The majority of tsunamis originate from the Pacific Ocean. This ocean is not "pacific" at all, as more than three fourths of all active volcanoes of the Earth are hidden on its bottom. Unfortunately, tsunami forecasting remains a complicated task, waters continue to take away hundreds of thousands of lives. Firstly, not every earthquake results in a tsunami, secondly, dangerous waves are not seen from ships or satellites in the majority of cases. Sometimes, the waves running at an aircraft's speed are small at the depth but they turn into billows near the coast.
Researchers are trying to determine how and where the tsunami will spread and how dangerous it can be to coastal zone inhabitants. To this end, firstly, tsunami recorders and tsunamometers should be installed in the ocean. By the way, such devices have been installed by the US environment protection laboratory - PMEL NOAA - in seven points of the Pacific Ocean. They allow to transmit up to 98 percent of data and to measure tsunamis with the amplitude of less than one centimeter. Once the first tsunami data becomes available, it should be processed quickly and accurately with the help of mathematical models, the forecast should be made and people should be warned about possible danger.
A group of Siberian researchers (the Sobolev Institute of Mathematics, Siberian Branch of Russian Academy of Sciences, Novosibirsk State University, Krasnoyarsk, etc.) has developed such software module. Special algorithm determines the tsunami source by processing records from deep-water oceanic receivers. The researchers built the software into the tsunami forecast system and tested it - the method worked perfectly well. The first calculations are performed right after the first wave reaches the closest tsunami analysis station. This provides the first order forecast. When the wave reaches the next station, the computations are repeated for both stations thus obtaining the second order forecast and so on.
However, the researchers say that the preliminary calculation system still needs significant improvement. They developed three new independent circulation methods for tsunami forecasting. "The methods applied to tsunami data circulation can also be used for investigation of the problem of optimal recording station placement in the ocean. Additional stations should be installed in locations that provide the most effective forecast", says Mikhail Lavrentiev, Russian project manager.
To raise the tsunami forecasting quality, the researchers suggest that the models should include special algorithm for determining initial shift in tsunami source based on two-dimensional inverse problem solution. This algorithm allows to restore the tsunami source by records of its waves at recently created stations. The researches claim that the development of neuronet software module will help to define more precisely the initial shift in the source.
Russian scientists’ large-scale project intended to improve the tsunami forecasting quality will also assist in finding appropriate locations for placement of new deep-water oceanic stations. The researchers are planning to test new investigations at the Pacific and Alaska tsunami notification centers.

© copyright 2006 by innovations-report.
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    В России начинаются клинические испытания вакцины против птичьего гриппа, которые будут завершены в августе.

MOSCOW - Russian scientists will know later this summer how successful the country's first bird flu vaccines are.
They have launched a trial involving 120 adult volunteers who are testing two types of vaccine. Officials say the testing will end in late August.
Three clinical trials on animals have scientists expressing "cautious optimism" that the vaccines will be efficient.
The bird flu virus has killed more than 120 people worldwide since last 2003 when it began ravaging Asian poultry stocks. Most human cases are linked to contact with infected birds.
Experts fear the H-Five-N-One virus will mutate into a form that spreads easily among people.

Copyright 2006 Associated Press. All rights reserved.
© Copyright 2001 - 2006 WorldNow and KRON. All Rights Reserved.
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    Laboratory Talk - UK / 7 June 2006
    Russia opens new nanotech center with FEI tools
    FEI plays key role in Moscow's new pilot scientific and technical center of excellence for nanotechnology development

    В Москве открыт экспериментальный научно-технический центр развития нанотехологий. Центр даст исследователям и разработчикам со всей России доступ к передовым системам и приборам, часть которых предоставила американская компания FEI, производитель электронных микроскопов и другого оборудования для наблюдение и манипулирования отдельными атомами и молекулами.

FEI reports that three of its systems, including Tecnai T12 and T30 transmission electron microscopes (TEMs) and a Quanta 3D DualBeam, have been selected as core enabling tools for Russia's new pilot scientific and technical center of excellence for nanotechnology development. The state-of-the-art centre will give researchers and developers from across the Russian Federation access to advanced nanoscale imaging, analysis and manipulation capabilities. The multi-million dollar center is being funded by the Russian Federation.
It is anticipated that Russia's overall investment in nanotechnology development will exceed $400 million in 2007. Globally, combined government investment in nanotechnology development is expected to reach $5 billion in 2006.
Private investments by corporations are expected to exceed the government number for the first time ever, reaching nearly $6 billion this year.
"Government nanotechnology investments were initially led by Europe, North America and Japan," commented Sean Murdock, executive director of the US-based NanoBusiness Alliance.
"Now countries such as Russia, China, Brazil and India have joined the trend and are making significant investments".
"As the nanotechnology era builds momentum, it is being recognized not only as a tool for economic development, but the scale at which all future scientific and product breakthroughs will take place".
"We are excited that a US company such as FEI plays such a vital role in enabling nanotechnology development around the world".
The Tecnai T12 and T30 systems have been purchased by the Russian center.
The third system, the Quanta 3D DualBeam, is being supplied by Systems for Microscopy and Analysis, FEI's sales agent in Russia.
FEI and Systems for Microscopy and Analysis look forward to working closely with the Center of Excellence to further develop methods and applications for characterization and manipulation at the nanoscale.
The Pilot Scientific and Technical Center of Excellence for Nanotechnology Development is located in Moscow. It was opened officially by Russian officials on June 3, 2006.
The Russian delegation was led by professor Michail V Kovalchuk, secretary of the council for science, technology and education under the Russian Federation's president, Vladimir Putin.
Under secretary of commerce for technology for the united States Robert Cresanti and Bob Gregg, executive vice president of sales and service for FEI, participated in the opening ceremonies.
It was Cresanti's first trip to Russia since he became president Bush's under secretary for technology in March.
"We at FEI are honored to be selected as a partner to support the work of Russia's new world-class center of excellence," commented Bob Gregg of FEI.
"We are also proud that we are not only providing some of the best enabling tools available, but that we are helping the world's leading researchers and developers create new products and technologies".
"These advances are expected to address key global issues and to enhance our quality of life around the globe." FEI's Tools for Nanotech, featuring focused ion- and electron-beam technologies, deliver 3D characterization, analysis and modification capabilities with resolution down to the sub-Angstrom level and provide innovative solutions for customers working in nanobiology, nanoresearch and nanoelectronics.
With R+D centers in North America and Europe, and sales and service operations in more than 50 countries around the world, FEI is bringing the nanoscale within the grasp of leading researchers and manufacturers and helping to turn some of the biggest ideas of this century into reality.

Copyright © 2000-2006 Pro-Talk Ltd, UK.
* * *
    Намеченная на 2018 год марсианская экспедиция обойдется в несколько раз дешевле, если использовать при ее подготовке новые технологии, разработанные российскими учеными. По мнению исследователей, сэкономить можно на транспортных расходах. Ученые разработали технологию, позволяющую делать легкие и эффективные солнечные батареи более дешевыми методами, а также способы, позволяющие использовать электрические двигатели практически на всем пути к Марсу и обратно. Финансовую поддержку ученым оказал Международный научно-технический центр.

At the very least the planned Martian expedition of 2018 will prove to be five times cheaper if its preparation utilises new technologies developed by Russian scientists. The researchers believe that such considerable savings can be made on transport costs.
The authors' basic premise lies in the reduction of costs on obtaining energy en route and in its more rational use. In other words, the scientists have not only developed a technology that can make light and effective solar batteries in cheaper ways, but they have also found design solutions that enable the use of electric engines for almost the entire journey to Mars and back. Financial support for the scientists comes from the International Science and Technology Centre.
The first thing that the scientists propose to lighten the load, both literally and figuratively, is a new design of solar batteries for space. The researchers attempted to replace crystalline silicon and the even more expensive gallium arsenide with relatively inexpensive amorphous silicon. This replacement foresees a double advantage.
Amorphous silicon can be sprayed by the metre onto a substrate ribbon and this is undoubtedly cheaper and technologically simpler than to stick pre-cultivated silicon crystals onto thin substrates.
However by itself amorphous silicon is a poor replacement for the crystalline version. To enhance the performance attributes of batteries made on its basis, the scientists have developed a special technology. Using an ultrafine laser beam and high-precision apparatus for its guidance, the authors learned to create "quantum pits" in the initially irregular silicon layer, sections that are 2nm in size with a pre-set atomic structure. Situated in a strict order at a distance of 10nm from one another, these sections create a kind of artificial order in the silicon layer, transforming it into something akin to a genuine crystal. Such a pseudo-crystal in a battery works almost as effectively as a real one and the scientists' forthcoming plans involve the gaining of 15% performance on these batteries.
If the steel substrate of the batteries is made thinner that usual, not 100 microns but 20 (and the researchers have already debugged this technique), the overall weight of the solar batteries will fall accordingly and, proportionately, the costs involved in getting them off the Earth and into space. This is where the savings come from; there is no need to lug superfluous tons of steel and fuel into space.
As a result the scientists calculate that there should be sufficient electrical energy to fly "on electricity" and not on liquid fuel. To provide the required speed for the spacecraft, the authors have developed a new version of electric engine that operates not on xenon, a very rare and therefore expensive option, but on krypton or even (potentially) on argon.
"To date engines of this kind have been used in the main on small satellites and then only to turn the satellite around," explains one of the project authors, the head of this direction at the Keldysh Research Centre Vitaly Semenov. "Xenon is used to create pull in them. This choice is not made by chance either. External electrons in solid atoms of this gas are situated far from the nucleus and, to "isolate" them, to transform the gas into ionized plasma, is a relatively simple matter. Then the ready ionized xenon is dispersed in electrical fields and we achieve high speeds of its flow, thanks to which the craft moves in cosmic space."
"Our solar batteries can "get hold of" sufficient energy in space to ionize cheaper and more accessible inert gases – krypton and argon. Of course this requires considerable energy expense compared with xenon, but the solar batteries and transformers are also specially designed, and they can handle this task."
"As a result of these and certain other improvements, the costs of a Martian expedition will fall from $100 billion to $16-20 billion. Of course, the precise figures will be determined to a greater degree of accuracy by the project participant countries, and these issues are already of a political kind. As far as the scientific side of the matter is concerned, the preliminary research conducted by our team and our colleagues from the Korolev RSC Energia, Krasnaya Zvezda, IKI RAS and IMBP RAS has proved, at least in the laboratory and partially in orbital experiments, that our technologies do work and that they work very well. Further research is required, but the work done to date enables us to hope for the success both of our developments and for the Mars expedition as a whole."

© ISTC 1993-2006.
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Продолжение дайджеста за ИЮНЬ 2006 года (часть 2)
январь февраль март апрель май июнь июль август сентябрь октябрь ноябрь декабрь

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