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Peculiarities of Ethylene Polymerization Reactions with Bis(imino)pyridyl Complexes of CoCl_(2) and FeCl_(2)

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Chinese Journal of Polymer science 2024年第4期42卷 492-500页

作者： Laura A.Rishina yury V.Kissin svetlana s.Lalayan Artem A.Antonov vadim G.Krasheninnikov Alexander A.Gulin N.N.semenov Federal Research Center for Chemical Physics Russian Academy of Sciences4 Kosygin St.Moscow119991Russia Department of Chemistry and Chemical Biology RutgersThe State University of New Jersey123 Bevier Rd.PiscatawayNJ08854USA Boreskov Institute of Catalysis Russian Academy of Sciences5 Lavrentieva Prosp.Novosibirsk630090Russia

The article describes ethylene polymerization reactions with transition metal catalysts based on complexes of CoCl_(2) and FeCl_(2) with an N,N,N-tridentate ligand 2,6-bis[1-(2,6-dimethylphenylimino)ethyl]pyridine. The complexes are converted into polymerization catalysts by reacting them either with polymethylalumoxane (MAO) or with a combination of Al(C2H5)2Cl and Mg(C4H9)2 at an [Al]:[Mg] ratio of ~3. Both MAO-activated complexes readily polymerize ethylene at 35 ℃ with the formation of linear, low molecular weight polymers with a narrow molecular weight distribution. The same complexes, when activated with the Al(C2H5)2Cl-Mg(C4H9)2 combination, form multi-center catalysts and generate polyethylenes with a broad molecular weight distribution.

关键词： Ethylene polymerization Bis(imino)pyridyl complexes of CoCl_(2)and FeCl_(2) Molecular-weight distribution Polymer chain structure

Thermo-and pH-sensitive Polymer with Pendant spacer-linked Imidazole Cycles

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Chinese Journal of Polymer science 2024年第4期42卷 437-445页

作者： Natalya V.Zakharova stanislav N.Zelinskiy Mariya s.strelova Elena N.Danilovtseva vadim V.Annenkov Institute of Macromolecular Compounds of the Russian Academy of sciences Saint Petersburg199004Russia Limnological Institute of siberian Branch of the Russian Academy of sciences Irkutsk664033Russia

By the reaction of poly(acryloyl chloride) with N-(3-aminopropyl)imidazole, poly(N-(3-(1H-imidazol-1-yl)propyl)acrylamide) was synthesized. The new polymer contains an imidazole ring removed from the main chain by a spacer of five bonds. The structure and purity, molecular weight, hydrodynamic and thermosensitive properties of the obtained sample were studied by1H-and13C-NMR, FTIR spectroscopy, acid-base titration, light scattering, turbidimetry and viscometry. The observed ability of the imidazole-containing polymer to form and destroy associates in water-salt solutions at pH 6.6-7.4 and temperatures of 29-48℃ indicates that these are promising candidates for designing complex biomedical systems. The new polymer is able to form complexes with oligo-DNA more actively than poly(1-vinylimidazole), which is of interest for gene delivery applications. The polymer cross-linked with epichlorohydrin gives micro-relief coatings on the plastic surface, and the modified surface is able to attach negatively charged objects. This thermo-and pH-sensitive polymer modification can be applied to create finely controlled surfaces for cell culturing.

关键词： Imidazole-containing polymer Thermolability pH-sensitivity The modified surface DNA immobilization

Production of the X(4014)as the spin-2 Partner of X(3872)in e^(+)e^(-)Collisions

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Chinese Physics Letters 2024年第3期41卷 30-36页

作者： Pan-Pan shi vadim Baru Feng-Kun Guo Christoph Hanhart Alexey Nefediev CAs Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China school of Physical sciences University of Chinese Academy of SciencesBeijing 100049China Departamento de F′ısica Te′orica and IFIC Centro Mixto Universidad de Valencia-CSIC Institutos de Investigaci′on de PaternaAptdo.2208546071 ValenciaSpain Institut fur Theoretische Physik II Ruhr-Universitat BochumD-44780 BochumGermany Peng Huanwu Collaborative Center for Research and Education Beihang UniversityBeijing 100191China Institute for Advanced simulation Institut fur Kernphysik and Julich Center for Hadron PhysicsForschungszentrum JulichD-52425 JulichGermany Jozef stefan Institute Jamova 391000LjubljanaSlovenia CeFEMA Center of Physics and Engineering of Advanced MaterialsInstituto Superior T′ecnicoAvenida Rovisco Pais 11049-001 LisboaPortugal

In 2021,the Belle collaboration reported the first observation of a new structure in theψ(2s)γfinal state produced in the two-photon fusion *** the hadronic molecule picture,this new structure can be associatedwith the shallow isoscalar D*D* bound state and as such is an excellent candidate for the spin-2 partner of the X(3872)with the quantum numbers J^(PC)=2^(++)conventionally named X_(2).

关键词： process X(3872) Collisions

Lattice-based digital signatures

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National science Review 2021年第9期8卷 9-10页

作者： vadim Lyubashevsky Zurich Research Laboratory IBM Research

Digital signatures and key exchange protocols are the two most important public key cryptographic primitives used in the electronic transmission of data. The goal of key exchange is to preserve the secrecy of the communication, while the goal of digital signatures is to guarantee the authenticity of the exchanged messages. Constructions of digital signature schemes based on classical mathematical assumptions appeared shortly following the invention of public key cryptography in the late 1970s. And just like with key exchange,

关键词： lattice cryptography digital signatures standardization

Russian Nuclear Rocket Engine Design for Mars Exploration

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Tsinghua science and Technology 2007年第3期12卷 256-260页

作者： vadim Zakirov Vladimir Pavshook Tsinghua space Center School of AerospaceTsinghua University Russian Research Center "Kurchatov Institute" Kurchatov Sq.1Moscow 123182Russia

This paper is to promote investigation into the nuclear rocket engine （NRE） propulsion option that is considered as a key technology for manned Mars exploration. Russian NRE developed since the 1950s in the former soviet Union to a full-scale prototype by the 1990s is viewed as advantageous and the most suitable starting point concept for manned Mars mission application study. The main features of Russian heterogeneous core NRE design are described and the most valuable experimental performance results are summarized. These results have demonstrated the significant specific impulse performance advantage of the NRE over conventional liquid rocket engine （LRE） propulsion technologies. Based on past experience, the recent developments in the field of high-temperature nuclear fuels, and the latest conceptual studies, the developed NRE concept is suggested to be upgraded to the nuclear power and propulsion system （NPPs）, more suitable for future manned Mars missions. Although the NRE still needs development for space application, the problems are solvable with additional effort and funding.

关键词： nuclear rocket engine Mars exploration propulsion technology design

The Berezitovoe gold-polymetallic deposit(Upper Amur region,Russia)：structure,mineralogy and genetic aspects

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Geoscience Frontiers 2016年第3期7卷 483-494页

作者： Alexandr s. Vakh vadim G. Khomich Natalia G. Boriskina M. santosh far East Geological Institute Far East Branch of Russian Academy of Sciences 159 Prospect 100 let Vladivastoku Vladivostok 690022 Russia school of Engineering Far Eastern Federal University 8 Suhanova St. Vladivostok 690950 Russia Department of Earth sciences University of Adelaide SA 5005 Australia school of Earth sciences and Resources China University of Geosciences Beijing 29 Xueyuan Road Beijing 100083 China

The Berezitovoe deposit in the sergachi volcano-plutonic and metallogenic belt preserves evidence for polymetallic mineralization of multiple *** steeply dipping gamet-tourmaline-muscovite-quartz metasomatites（with K-Ar ages of 132 ± 2.9 and 127 ± 4.4 Ma） carry two distinct stages of mineralization developed at different times：（1） polymetallic mineralization and（2） *** deposit is located within Paleozoic gneissose granitoids of the Pikansky complex（dated as 379 ± 1.1 Ma by zircon U-Pb method） intruded by early Cretaceous porphyry-like granites of the Haikta pluton（dated as137 ± 0.67 Ma by zircon U-Pb method） and late Cretaceous dikes of porphyrites,porphyries,and *** suggests the action of late gold-bearing hydrothermal fluids on the early polymetallic ores and the selective mobilization of some elements from these lead to redeposition together with complex sulphosalts.

关键词： Amur River head Gold Early Cretaceous Metallogeny Tectonics

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俄罗斯的国家转型(1991-2021年)

俄罗斯研究 2024年第4期 62-73页

作者：瓦迪姆·沃尔科夫杨辉(翻译) 俄罗斯圣彼得堡欧洲大学山东第二医科大学外国语学院

要讨论俄罗斯的国家转型问题,需要首先明确与国家有关的核心概念,并综合分析苏联解体后30年的俄罗斯政治、经济和社会的变迁来探讨。国家被定义为在一定领土上维持合法暴力垄断的有组织的社会。国家的基本功能包括司法治理、税收、保护... 详细信息

要讨论俄罗斯的国家转型问题,需要首先明确与国家有关的核心概念,并综合分析苏联解体后30年的俄罗斯政治、经济和社会的变迁来探讨。国家被定义为在一定领土上维持合法暴力垄断的有组织的社会。国家的基本功能包括司法治理、税收、保护领土、解决争端等。20世纪90年代,苏联解体之后,俄罗斯经历了国家垄断地位的崩溃、私有化过程中寡头经济体系的出现、逃税和影子经济的蔓延,以及非法暴力集团和非正式权力结构联邦权力的挑战。普京上台后,通过打击寡头、改革税收、加强中央权威等措施,恢复了国家自主能力,包括控制关键经济领域和改善司法系统等措施。俄罗斯建立了以国家控制为特征的资本主义模式,国家掌控能源、基础设施等关键行业,并通过国有银行和主权基金来管理石油和天然气的出口收入。在国际压力和制裁的背景下,俄罗斯加强了内部政治控制,消除政治竞争对手和外国影响力,加强了警察和法院系统,推进了数字化国家服务,并增加了国防预算。今后阶段的俄罗斯国家发展仍存在很多不确定性,未来趋势难以预测,但自主脱离外部利益和以内部投入替代外部参与是十分重要的。

关键词：俄罗斯国家转型俄罗斯国家能力俄罗斯国家建构国家资本主义

Chronology and Geochemistry of the Berezitovoe Polymetallic Gold Deposit in Eastern siberia, Russia and its Geological significance

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Acta Geologica sinica(English Edition) 2017年第5期91卷 1733-1750页

作者： ZHANG Guobin yANG yanchen Alexander s.VAKH vadim G. KHOMICH WANG Keyong yE songqing HAN shijiong Department of Geology Liaoning Technical University College of Earth sciences Jilin University Far East Geological Institute Far East Branch Russian Academy of Sciences

The Berezitovoe deposit is a large-sized Au-Ag-Zn-Pb deposit in the east of the selengastanovoi superterrane, Russia. Au-Ag orebodies are hosted by tourmaline-garnet-quartz-muscovite metasomatic rocks; Zn-Pb orebodies are hosted by granodiorites, porphyritic granites and tourmalinegarnet-quartz-muscovite metasomatic rocks. These orebodies are surrounded by wall rocks dominated by the Tukuringra Complex granodiorites, porphyritic granites, and gneissic granodiorites. The alteration includes silicification and garnet, sericitization chloritization, carbonatization and kaollinization. LA-ICP-Ms U-Pb zircon dating indicates that the gold mineralization can be divided into two stages in the Berezitovoe polymetallic gold deposit（at 363.5 ± 1.5 Ma, and133.4± 0.5）.Hornblende-plagioclase gneisses of the Mogocha Group in the study area underwent Paleoproterozoic metamorphism（at 1870 ± 7.8 and 2400 ± 13 Ma）, gneissic granodiorite of the Tukuringra Complex yields a late Paleozoic magmatic age（at 379.2 ± 1.1 Ma）,and subalkaline porphyritic granitoid of the Amudzhikan Complex yield late Mesozoic magmatic ages（133-139 and 150-163 Ma）. Granodiorites of the Tukuringra Complex in the study area have high concentrations of siO_2（average of 60.9 wt%）, are aluminum-oversaturated（average A/CNK of 1.49）, are enriched in the large ion lithophile elements（e.g.,K, Rb, and Ba）, U, Th, and Pb, are depleted in high field strength elements（e.g., Ta, Nb, and Ti）, and have slightly negative Eu and no Ce anomalies in chondrite-normalized rare earth element *** inclusions from quartz veins include three types： aqueous two-phase, CO2-bearing three-phase,and pure CO2. Aqueous two-phase inclusions homogenize at 167℃-249℃ and have salinities of 4.32%-9.47% NaCl equivalent, densities of 0.86-0.95 g/cm^3, and formed at depths of 0.52-0.94 km. In comparison, the CO2-bearing three-phase inclusions have homogenization temperatures of 265℃-346℃,salinities of 7.14%-11.57% NaCl equivalent, and total

关键词： Geochemistry U-Pb zircon dating fluid inclusions Berezitovoe polymetallic gold deposit Eastern siberia Russia

Liver regeneration is associated with lipid reorganization in membranes of the endoplasmic reticulum

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Frontiers in Biology 2016年第5期11卷 396-403页

作者： Anatoly I. Bozhkov Natalia G. Menzyanova vadim V. Davydov Natalia I. Kurguzova vadim I. sidorov Anastasia s. Vasilieva Research Institute of Biology of V.N. Karazin Kharkov National University sq. Svobody 4 61022 Kharkov Ukraine Institute of Fundamental Biology and Biotechnology of siberian Federal University pr. Svobodny 79 660041 Krasnoyarsk Russia Ryazan state Medical University named after academician I.P.. Pavlov Visokovoltnaya 9 390026 Ryazan Russia

BACKGROUND： In recent years, an adaptive endoplasmic reticulum （ER） stress response has been actively investigated. The ER membrane, isolated from the intact and regenerating liver, may be an appropriate model for investigating the association between structural and functional characteristics of ER in vivo and their corresponding behavioral characteristics in vitro. The rate of lipid synthesis and that of intracellular lipid exchange between the ER and cytosol were investigated in the intact and regenerating liver （13 h after partial hepatectomy）. Particularly, membrane characteristics, surface potential, and glucose 6- phosphatase （G6Pase） activity were investigated, along with the degradation rate of G6Pase in vitro, which was estimated by the loss of G6Pase activity, formation of lipid peroxides, and size of excreted membrane vesicles. METHODs： The rate of lipid synthesis was determined by measuring the intensity of radioactive precursor （C^14-sodium acetate） in different fractions of lipids （phospholipids, non-esterified fatty acids, and triacylglycerides） after 30 min exposure. The rate of lipid metabolism was assessed by measuring the quantity oflipids with radioactive labels emerging in the cytosol of hepatocytes （CPM）. Viscosity and surface potential were determined by fluorescent probes. REsULTs： It was observed that after 13 h of partial hepatectomy, the rate of lipid synthesis in the ER of hepatocytes in the regenerating liver was 3 times lower than that in ER ofhepatocytes in the intact liver, wherein the rate of incorporation of newly synthesized lipids in cytosol was several times higher in the regenerating liver. Increase in the rate of exchange of neutral lipids in cells of the regenerating liver was accompanied by lipid reconstruction in the ER, changing the structural and functional characteristics of the membrane. such membrane rebuilding also contributed to the rate of degradation of the ER in vitro, which that must be taken into account during d

关键词： regeneration neutral lipids microsomes in vitro