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Formation of Multicharged Metal Ions in Vacuum Arc Plasma Heated by Gyrotron Radiation

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Plasma Science and Technology 2011年第5期13卷 596-599页

作者： G. Yu. YUSHKOV K. P. SAVKIN A. G. NIKOLAEV E. M. OKS A.V. VODOPYANOV I. V. IZOTOV D. A. MANSFELD high current electronics institute Siberian Branch of Russian Academy of Sciences Tomsk 634055 Russia institute of Applied Physics Russian Academy of Science Nizhniy Novgorod 603950 Russia

A new method for the generation of high charged state metal ion beams is developed. This method is based on microwave heating of vacuum arc plasma in a magnetic trap under electron cyclotron resonance （ECR） conditions. Two gyrotrons for plasma heating were used, which were with the following parameters. The first is with a wave frequency of 37.5 GHz, a pulse duration of 1 ms and power of 100 kW, another is with 75 GHz, 0.15 ms and 400 kW. Two different magnetic traps were considered for vacuum arc plasma confinement. The first one is a simple mirror trap. Such system was already investigated and could provide high charge state ions. The second trap was with a cusp magnetic field configuration with native ＂minimum-B＂ field structure. Two different ways of metal plasma injection into the magnetic trap were used. The first one is an axial injection from an arc source located out of the trap, and the second is a radial injection from four arc sources mounted at the center of the trap. Both traps provide up to 200 eMA of ion beam current for platinum ions with highest charge state 10＋. Ion beams were successfully extracted from the plasma and accelerated by a voltage of up to 20 kV.

关键词： ion source ECR heating vacuum arc multicharged ions

Focused electron beam transport through a long narrow metal tube at elevated pressures in the forevacuum range

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Plasma Science and Technology 2023年第1期25卷 128-134页

作者： Ilya BAKEEV Kirill KARPOV Aleksandr KLIMOV Efim OKS Aleksey ZENIN Tomsk State University of Control Systems and Radioelectronics Tomskaâ634050Russia institute of high current electronics Siberian BranchRussian Academy of SciencesTomskaâ634055Russia

We present here our investigations of the features of focused electron beam transport in free space at elevated pressures of a few *** have explored the effect of the beam accelerating voltage,operating gas pressure,and magnetic focusing upon the trajectory of beam electrons in the crossover region,in particular on the beam convergence and divergence *** is shown that for the forevacuum pressure range of 2-5 Pa explored,a distinctive feature of the propagation of a focused electron beam with a current of up to 20 mA at an accelerating voltage of 10-20 kV is the difference in the angles of convergence(before the focus)and divergence(after the focus).Whereas at a low pressure of 2 Pa the divergence angle is smaller than the convergence angle,as the pressure increases the divergence angle increases and for pressures greater than 5 Pa the divergence angle is greater than the convergence *** results obtained were used in experiments on electron beam transport through a long narrow metal tube with a diameter of 5.8-9.2 mm and length of 10-30 *** show that for a 30 cm long tube of 7.5 mm diameter,the focused beam transmission can exceed 70%.

关键词： focused electron beam plasma electron source forevacuum pressure range long metal tube

Eurasia as the scene of the Late Cenozoic tectogenesis

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Geoscience Frontiers 2012年第5期3卷 559-569页

作者： G.F.Ufimtsev institute of the Earth's Crust sb ras Irkutsk 664033Russia

This paper attempts to review the descriptions on the genetic series of neotectonic forms in Eurasia. Morphotectonically, the Eurasian continental block exhibits a radial-concentric pattern consist- ing of four kinds of tectonic units： platforms, rejuvenated and youthful mobile belts, and the continent- ocean transition zones. Vast areas of young and ancient platforms, such as Siberia, have experienced slow-rate Late-Cenozoic uplift and little interior deformation. The youthful orogenic belts are clustered into the giant Alpine-Himalayan megabelt. The rejuvenated mountain belts are characterized by a variety of structural-morphological types of orogens, such as domelike uplifts, block uplifts and intermountain basins. The continent-ocean transition zones in Eastern Asia, including marginal rifts and extensional basins, are resulted from interaction between the continental block and Pacific Ocean and Philippine Sea since the Late Cenozoic. One of the conspicuous features of Eurasia is that most areas lie in the largest geoid depression of the Earth, and the NS trending Uralian-Oman lineament expresses a break on the geoid slope, implying a relationship to deep structure, including density inhomogeneities, down- ward to the core-mantle interface. Besides, the Eurasian continent fully demonstrates morphotectonic and recent geodynamic features of the Northern Hemisphere of the Earth, just in contrast to that of the Southern Hemisphere. It is best to view the surface morphotectonics and deep structure of the Earth as a geodynamic ensemble which has spawned the large-scale geomorphic features on the surface.

关键词： Morphotectonics Tectonic units Geoid Geodynamic ensembleEurasia

Growth rate of CO_(2) hydrate film on water-oil and water-gaseous CO_(2) interface

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Chinese Journal of Chemical Engineering 2023年第4期56卷 266-272页

作者： Tatyana P.Adamova Sergey S.Skiba Andrey Yu.Manakov Sergey Y.Misyura Kutateladze institute of Thermophysics sb ras Lavrentiev Ave.1Novosibirsk 630090Russian Federation

It is known that injection of carbon dioxide into the petroleum reservoir(CO_(2) flooding) is one of the effective methods for enhanced oil recovery. CO_(2) flooding may be complicated by formation of CO_(2) hydrate plugs. It makes topical investigation of CO_(2) hydrate formation in the system gaseous CO_(2)-oil-water. In this work, the growth rates of carbon dioxide hydrate films at the water-oil as well as the water-gas interface are studied in the pressure range of 2.30-3.04 MPa and at temperatures between -5.4 and 5.0℃. It is found that the growth rate for the water-oil interface is 3.5 times lower than that for the water-gas interface with carbon dioxide. It is hypothesised that the observed decrease in the growth rate is related to the mechanical resistance of the oil components adsorbed on the interface to the growth of the hydrate film. The growth rate of the film has been shown to depend on the experimental procedure,most likely due to the different initial concentrations of carbon dioxide in the aqueous solutions.

关键词： Gas hydrate Oil Carbon dioxide Growth rate Hydrate film

Effect of WC/Ni-Cr additive on changes in the composition of an atmospheric residue in the course of cracking

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Petroleum Science 2020年第2期17卷 499-508页

作者： Galina S.Pevneva Natalya G.Voronetskaya Nikita N.Sviridenko Anatoly K.Golovko institute of Petroleum Chemistry sb ras 4 Akademicheskiy AveTomskRussia 634055

The paper presents the results of investigation of changes in the composition of hydrocarbons and sulfur-containing compounds of an atmospheric residue in the course of cracking in the presence of a tungsten carbide-nickel-chromium(WC/Ni-Cr)catalytic additive and without *** cracking is carried out in an autoclave at 500℃for 30 *** addition of the WC/Ni-Cr additive promotes the deepening of reactions of destruction not only of resins and asphaltenes,but also high molecular weight naphthene-aromatic compounds of the atmospheric *** is shown that the content of low molecular weight C9-C17 n-alkanes and C9-C10 alkylbenzenes rose sharply in the products of cracking with addition of WC/Ni-Cr in comparison with those produced without the ***-and naphthene-substituted aromatic hydrocarbons of benzene,naphthalene,phenanthrene series,polyarenes,benzo-and dibenzothiophenes are identified.

关键词： Atmospheric residue Cracking Catalytic additive Hydrocarbons Composition

The Dependence of Stellar Activity Cycles on Effective Temperature

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Research in Astronomy and Astrophysics 2022年第12期22卷 198-210页

作者： Leonid Kitchatinov institute of Solar-Terrestrial Physics sb ras Lermontov Str.126AIrkutsk 664033Russia

This paper proposes the idea that the observed dependence of stellar activity cycles on rotation rate can be a manifestation of a stronger dependence on the effective temperature. Observational evidence is recalled and theoretical arguments are given for the presence of cyclic activity in the case of sufficiently slow rotation only. Slow rotation means proximity to the observed upper bound on the rotation period of solar-type stars. This maximum rotation period depends on temperature and shortens for hotter stars. The maximum rotation period is interpreted as the minimum rotation rate for operation of a large-scale dynamo. A combined model for differential rotation and the dynamo is applied to stars of different mass rotating with a rate slightly above the threshold rate for the *** show shorter dynamo cycles for hotter stars. As the hotter stars rotate faster, the computed cycles are also shorter for faster rotation. The observed smaller upper bound for rotation period of hotter stars can be explained by the larger threshold amplitude of the α-effect for onset of their dynamos: a larger α demands faster rotation. The amplitude of the(cycling) magnetic energy in the computations is proportional to the difference between the rotation period and its upper bound for the dynamo. Stars with moderately different rotation rates can differ significantly in super-criticality of their dynamos and therefore in their magnetic activity, as observed.

关键词： dynamo stars:activity stars:magnetic field stars:solar-type stars:rotation

Grade characteristics in surface layer of TC4 titanium alloy caused by pulsed electron beam treatment

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Grade characteristics in surface layer of TC4 titanium alloy...

Crystal Structures of Tris-dipivaloylmetanates of Tm^3＋ and Yb^3＋

第十届中俄双边新材料新工艺研讨会

作者： Yu.F.Ivanov N.N.Koval institute of high-current electronics sb ras Academichesky ave.Tomsk634055Russia

＜正＞TC4 titanium alloy was employed to pulsed electron beam treated and the distribution along surface layer was investigated by Nano-indent analysis *** characteristics of grade characteristics were analyzed by studying the distribution of hardness and yield strength along surface layer of specimens which were electron beam treated specimens by *** correlation of hardness to microstructure was analyzed and the reason of forming grade fine grain microstructure was *** temperature grade or heat effect caused by pulsed electron beam treatment is the main reason to form grade fine grain microstructure in surface layer.

关键词： pulsed electron beam treatment grade characteristics nanoindent

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Chinese Journal of Structural Chemistry 2018年第4期37卷 640-644页

作者：黄燊 Sysoev Sergey Viktorovich Stabnikov Pavel Aleksandrovich Pervukhina Natalia Viktorovna Korolkov Ilia Viktorovich Mosyagina Svetlana Andreevna Nikolaev institute of Inorganic Chemistry SB RAS Novosibirsk State Technical University

A series of Ln（Ⅲ） dipivaloylmethanates Ln（dpm）3 has been obtained. The crystalstructures of Tm（dpm）3 （1） and Yb（dpm）3 （2） were determined by X-ray analysis at 200（2） K（Pmn2b Z = 2; a = 17.7509（8）, b = 10.5805（4）, c = 9.8380（4） A, V = 1847.7（1） A3 for （1） and a =17.7272（6）, b = 10.5882（3）, c = 9.8440（3） A, V= 1847.7（1） A^3 for （2））. These data complete thestructural evaluation of lanthanoid tris-dipivaloylmethanates. Compounds 1 and 2 are isostructuralto the complexes Ln（dpm）3 （Ln -- Er and Lu）. It is demonstrated that the volatility of tris-dipivaloylmethanates of rare earth elements increases from the complex of Lu to that of La.

关键词： dipivaloylmethanate Ln(Ⅲ) X-ray crystal structure volatility

Fossil history of Mesozoic weevils （Coleoptera： Curculionoidea）

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Insect Science 2012年第6期19卷 683-698页

作者： Andrei A. Legalov Laboratory of Phylogeny and Faunogenesis Institute of Systemafics and Ecology of Animals SB RAS Novosibirsk Russia

The first synopsis of Mesozoic weevils （Curculionoidea： Coleoptera） is pre- sented. Changes of family, genera and species abundance during the Mesozoic revealed three distributional patterns. The Jurassic （Karatau） fauna was dominated by the Nemony- chidae. During the Early Cretaceous （beginning at the Jurassic/Cretaceous border）, the Ithyceridae was the prevalent group with a significant role played by the Nemonychidae. In the Late Cretaceous （Cenomanian and Turonian）, the major groups were the Curculion- idae and Brentidae. Obviously, the change of weevil fauna during this period was due to the expansion of the angiosperms, which provided multiple niches in their vegetative and reproductive organs for weevil development.

关键词： Coleoptera Curculionoidea faunistic analysis fossil record Mesozoic,trophic levels