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Asphaltenes of Oil and Hydrocarbon Distillates as Nanoscale Semiconductors

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材料科学与工程（中英文b版） 2012年第2期2卷 151-157页

作者： Michail Yurievich Dolomatov sergey Vladislavovich Dezortsev Svetlana Aleksandrovna Shutkova Department of Physics Ufa State Academy of Economic and Service

The asphaltenes are composed mainly of polyaromatic carbon with NSO-compounds combined with traces vanadium and nickel, which are located in porphyrin structures. The asphaltenes have paramagnetic centers with concentration of free radicals on the level of 1019-1020 spin/g (EPR). The experiment and calculation results indicate that the molecular complexes of the asphalt-pitch substances associates in the structural units" formation on the nanomolecular level with the charge transfer properties involved. The spectra and quantum calculations indicate that the structures containing the aromatic rings, heteroaromatic rings and the corresponding free radicals are the most probable centers for the electron transfer. The calculations showed that the asphaltenes structural units, containing from 6 to 13 aromatic rings have the forbidden gap size from 4.92-6.49 eV - for the molecular fragments and from 2.84 to 3.20 eV, for the free radical form. This indicates the paramagnetic fraction of asphaltenes possible belonging to the amorphous compensatory organic broadband semiconductors. The experiments for the asphaltene molecules band gap estimation, confirmed by of computing ab-initio methods, showed, that the asphaltenes have nanomolecular structures and can be used as semiconductors for nanoelectronics.

关键词：半导体纳米材料多环芳烃沥青质自由基浓度馏分分子片段从头计算方法计算结果

基于血液动力模型的非侵入式肝纤维化诊断技术

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基于血液动力模型的非侵入式肝纤维化诊断技术

Nanoscale mapping of optically inaccessible bound-states-in-the-continuum

第十届全国疑难及重症肝病大会

作者：陈皓吴胜迪李振燕 sergey Klimov Alton b.“brad” Farris 蒋伟江毅 Georgia State University Mathematics and Statistic Department 上海复旦大学附属中山医院传染科石家庄第五医院超声科

研究目的和背景肝纤维化是由慢性肝病引起的肝脏损害并且已成为一个重大的公共卫生问题。当前早期肝纤维化仍旧难以精确诊断。虽然肝纤维化与肝组织硬度之间的强关联性已经被普遍认可,但是肝纤维化如何改变肝脏的物理特性,以及如何影响...

研究目的和背景肝纤维化是由慢性肝病引起的肝脏损害并且已成为一个重大的公共卫生问题。当前早期肝纤维化仍旧难以精确诊断。虽然肝纤维化与肝组织硬度之间的强关联性已经被普遍认可,但是肝纤维化如何改变肝脏的物理特性,以及如何影响肝脏血液的动力学特征仍然没有被理解。我们假设肝脏的组织刚性可影响血流动力学特性,同时无创血流测量可用于检测肝纤维化。

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来源： cnki会议评论

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Light(Science & Applications) 2022年第2期11卷 188-196页

作者： Zhaogang Dong Zackaria Mahfoud Ramón Paniagua-Domínguez Hongtao Wang Antonio I.Fernández-Domínguez sergey Gorelik Son Tung Ha Febiana Tjiptoharsono Arseniy I.Kuznetsov Michel bosman Joel K.W.Yang Institute of Materials Research and Engineering A*STAR(Agency for ScienceTechnology and Research)2 Fusionopolis Way#08-03 Innovis138634 SingaporeSingapore Department of Materials Science and Engineering National University of Singapore9 Engineering Drive 1117575 SingaporeSingapore Singapore University of Technology and Design 8 Somapah Road487372 SingaporeSingapore Departamento de Física Teórica de la Materia Condensada and Condensed Matter Physics Center Universidad Autónoma de Madrid28049 MadridSpain Singapore Institute of Food and biotechnology Innovation A*STAR(Agency for ScienceTechnology and Research)31 Biopolis Way#01-02 Nanos138669 SingaporeSingapore

bound-states-in-the-continuum(bIC)is an emerging concept in nanophotonics with potential impact in applications,such as hyperspectral imaging,mirror-less lasing,and nonlinear harmonic *** true bIC modes are nonradiative,they cannot be excited by using propagating light to investigate their optical *** this paper,for the 1st time,we map out the strong near-field localization of the true bIC resonance on arrays of silicon nanoantennas,via electron energy loss spectroscopy with a sub-1-nm electron *** systematically breaking the designed antenna symmetry,emissive quasi-bIC resonances become *** gives a unique experimental tool to determine the coherent interaction length,which we show to require at least six neighboring antenna *** importantly,we demonstrate that quasi-bIC resonances are able to enhance localized light emission via the Purcell effect by at least 60 times,as compared to unpatterned *** work is expected to enable practical applications of designed,ultra-compact bIC antennas such as for the controlled,localized excitation of quantum emitters.

关键词： antenna states mapping

Phylogeny of brucella abortus strains isolated in the Russian Federation

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Asian Pacific Journal of Tropical Medicine 2021年第7期14卷 323-329页

作者： Dmitry A.Kovalev Dmitriy G.Ponomarenko sergey V.Pisarenko Nikolay A.Shapakov Anna A.Khachaturova Natalia S.Serdyuk Olga V.bobrysheva Alexander N.Kulichenko Stavropol Research Anti-Plague Institute 355035StavropolRussian Federation

Objective: To study brucella(b.) abortus strains isolated in the Russian Federation, in order to identify their detailed position in the phylogenetic structure of the species global population as well as to determine genetic relationships for isolates from different geographical ***: based on bayesian method, the whole genome singlenucleotide polymorphism(SNP) analysis of 258 b. abortus strains from different geographical areas of the world including 20 b. abortus strains isolated in Russia was carried out. Results: The core genome SNP analysis of the b. abortus isolates allowed describing the main genetic lineages. The Russian strains entered two separate clades, including the basal branch and the C1 branch that is widely spread in Eurasia. The data on the isolation time was used for the dating of phylogenetic tree, and also the estimated time frame for the b. abortus genotype diversification was determined. There were sets of specific SNPs identified, which defined each of the genotypes and ***: A significant genetic diversity of the brucellosis pathogen strains from Russia has been proven. The sets of unique specific SNPs described in our study may become one of the elements within a bio-informational analysis algorithm to be used for epidemiological study of brucellosis outbreaks, including those caused by new(atypical) genetic variants of b. abortus.

关键词： brucella abortus Phylogeny Evolution Genome SNP

Differentiation of wild boar and domestic pig populations based on the frequency of chromosomes carrying endogenous retroviruses

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Natural Science 2010年第6期2卷 527-534页

作者： sergey V. Nikitin Nikolay S. Yudin sergey P. Knyazev Ruslan b. Aitnazarov Vitaliy A. bekenev Valentina S. Deeva Galina M. Goncharenko Victor F. Kobzev Margarita A. Savina Viktor I. Ermolaev 不详

Analysis of the frequencies of chromosomes carrying various classes of porcine endogenous retroviruses (PERVs) and combinations of these classes was performed in the swine species Sus scrofa L. by using maps constructed in two principal component coordinates. Four population clusters can be recognized in the maps. Cluster 1 is formed by wild boars,cluster 2 by domestic meat breeds, cluster 3 by meat-and-lard (universal) breeds, and cluster 4 by miniature pigs. The maps indicate that modern domesticated swine meat breeds are the closest to the wild type. Meat-and-lard domestic swine breeds are more distant from wild boars, and miniature pigs are diverged the most. The maps showed that microevolution processes associated with PERV carriership frequency had two basic dimensions, or vectors: the vector of fat deposition variation and the “minus” selection vector (determination of commercial traits). Thus, PERVs may cause variation in pig physiology.

关键词： Sus Scrofa Endogenous Retroviruses Pig Genetics Microevolution Genetic Distance De-termination

Evaluation of Carbon and Electron Flow in Lactobacillus brevis as a Potential Host for Heterologous 1-butanol biosynthesis

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Advances in Microbiology 2013年第5期3卷 450-461页

作者： Oksana V.berezina German Jurgens Natalia V.Zakharova Rustem S.Shakulov sergey V.Yarotsky Tom b.Granstrom State Research Institute of Genetics and Selection of Industrial Microorganisms MoscowRussian Federation Department of biotechnology and Chemical Technology School of Chemical TechnologyAalto UniversityEspooFinland

Heterofermentative lactic acid bacterium Lactobacillus brevis may be considered as a promising host for heterologous butanol synthesis because of tolerance to butanol and ability to ferment pentose and hexose sugars from wood hydrolysates that are cheap and renewable carbohydrate source. Carbon and electron flow was evaluated in two L. brevis strains in order to assess metabolic potential of these bacteria for heterologous butanol synthesis. Conditions required for generation of acetyl-CoA and NADH which are necessary for butanol biosynthesis have been determined. Key enzymes controlling direction of metabolic fluxes in L. brevis in various redox conditions were defined. In anaerobic glucose fermentation, the carbon flow through acetyl-CoA is regulated by aldehyde dehydrogenase ALDH possessing low affinity to NADH and activity (KmNADH= 200 μM, Vmax= 0.03 U/mg of total cell protein). Aerobically, the NADH-oxidase NOX (KmNADH= 25 μM, Vmax = 1.7 U/mg) efficiently competes with ALDH for NADH that results in formation of acetate instead of acetyl-CoA. In general, external electron acceptors (oxygen, fructose) and pentoses decrease NADH availability for native ethanol and recombinant butanol enzymes and therefore reduce carbon flux through acetyl-CoA. Pyruvate metabolism was studied in order to reveal redirection possibilities of competitive carbon fluxes towards butanol synthesis. The study provides a basis for the rational development of L. brevis strains producing butanol from wood hydrolysate.

关键词： Lactobacillus brevis Metabolism Carbon and Electron Flow Heterologous butanol Synthesis SO2-Ethanol-Water Hydrolysate

The Localization of Finely Dispersed Caesium Radioaerosols from Off-Gases

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Journal of Power and Energy Engineering 2014年第4期2卷 495-499页

作者： sergey A. Kulyukhin Vladimir V. Kulemin Viktor A. Lavrikov Igor A. Rumer Vladimir b. Krapukhin Vladimir V. Krapukhin Frumkin's Institute of Physical Chemistry and Electrochemistry Russian Academy of Sciences Moscow Russia NPP “FiltroSorb Technologies Ltd.” Moscow Russia

based on fundamental research, we developed the basic scheme of a decontamination setup to remove acid gases (HCl, SO2, NOx) from steam-air flows with simultaneous localization of radioactive aerosols, including aerosols with a particle size of less than 0.1 μm and volatile radioactive iodine compounds. The decontamination process is based on the method of the agglomeration cocrystallization of finely dispersed and other aerosols in the gas phase by including the aerosols in the inner structure of large-particle non-radioactive aerosols of ammonium salts, for example, NH4Cl or (NH4)2SO3. For 137Cs, the most ecologically dangerous long-lived radionuclide, the setup ensures a decontamination factor of 102 to 103 in one decontamination stage. because the setup consists of three consecutive stages of the same type, the cumulative decontamination factor can reach to 106 - 107. To localize radioactive iodine as I2, HI, HOI, HIO3, and CH3I from vapor-air flows, the setup uses a unit containing special granulated sorbents based on inorganic compounds. Developed at the Institute of Physical Chemistry, Russian Academy of Sciences, these sorbents effectively remove various radioactive iodine species (inorganic species and methyl iodide) from steam-air flows, ensuring decontamination factors of at least 104. The proposed technological scheme will allow vapor-gas flows to be cleaned of radioaerosols and all volatile radioactive iodine species at decontamination factors of not less than 104.

关键词： Aerosols Caesium Agglomeration Cocrystallization

The Study of Influence of Silica and Polyethilene Glycols Organic-Inorganic Compounds on Free-Radical Processes in Vitro

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Pharmacology & Pharmacy 2010年第2期1卷 69-74页

作者： Olga G. Sitnikova sergey b. Nazarov Irina V. Shikhanova Alexander V. Agafonov Jean A. Dyuzhev rina G. Popova 不详

In this study investigation of influence of hybrid nanosilica-polyethylene glycols materials (molecular weight 1500, 6000 and 15000), prepared by sol-gel synthesis, on lipid peroxidation and antioxidant activity of human serum in vitro was performed. Methods included chemiluminescence analysis and quantitative malonic dialdehyde estimation. It was revealed that nanosilica-PEG materials with different molecular weight had certain biological activity. Powders of SiO2-PEG 1500 and SiO2-PEG 6000 manifest prooxidant effects, whereas mesoporous (calcine) powders produced antioxidant effects in blood serum in vitro.

关键词： Free-Radical Oxidation Nanosilica Chemiluminescence Malonic Dialdehyde

Intrinsic and Extrinsic Exciton Recombination Pathways in AgInS_(2)Colloidal Nanocrystals

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Energy Material Advances 2021年第1期2021卷 165-174页

作者： Matteo L.Zaffalon Valerio Pinchetti Andrea Camellini sergey Vikulov Chiara Capitani bing bai Meng Xu Francesco Meinardi Jiatao Zhang Liberato Manna Margherita Zavelani-Rossi Scott A.Crooker Sergio brovelli Dipartimento di Scienza dei Materiali Universitàdegli studi di Milano-Bicoccavia Roberto Cozzi 5520125 MilanoItaly Dipartimento di Energia Politecnico di MilanoVia Ponzio 34/320133 MilanoItaly Istituto Italiano di Tecnologia Via Morego 3016163 GenovaItaly Glass to Power SpA Via Fortunato Zeni 838068 RoveretoItaly beijing Key Laboratory of Construction-Tailorable Advanced Functional Materials and Green Applications School of Materials Science&EngineeringBeijing Institute of TechnologyBeijing 100081China IFN-CNR Piazza Leonardo da Vinci 3220133 MilanoItaly National High Magnetic Field Laboratory Los Alamos National LaboratoryLos AlamosNew Mexico 87545USA

Ternary I-III-VI2 nanocrystals(NCs),such as AgInS_(2) and CuInS_(2),are garnering interest as heavy-metal-free materials for photovoltaics,luminescent solar concentrators,LEDs,and *** origin of the emission and absorption properties in this class of NCs is still a subject of *** theoretical and experimental studies revealed that the characteristic Stokesshifted and long-lived luminescence of stoichiometric CuInS_(2) NCs arises from the detailed structure of the valence band featuring two sublevels with different *** same valence band substructure is predicted to occur in AgInS_(2) NCs,yet no experimental confirmation is available to ***,we use complementary spectroscopic,spectro-electrochemical,and magneto-optical investigations as a function of temperature to investigate the band structure and the excitonic recombination mechanisms in stoichiometric AgInS_(2) *** transmission measurements reveal the signatures of two subbands with opposite parity,and photoluminescence studies at cryogenic temperatures evidence a dark state emission due to enhanced exchange interaction,consistent with the behavior of stoichiometric CuInS_(2) *** the temperature as well as applying reducing electrochemical potentials further suppress electron trapping,which represents the main nonradiative channel for exciton decay,leading to nearly 100%emission efficiency.

关键词： parity valence applying