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Numerical Study of the Dynamic, Thermodynamic and Microstructural Parameters of Convective Clouds

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Natural Science 2018年第2期10卷 63-69页

作者： vitaly A. Shapovalov Alexander v. Shapovalov Boris P. Koloskov Ruslan Kh. Kalov valery N. Stasenko Department of Cloud Physics High-Mountain Geophysical Institute Nalchik Russia Autonomous Nonprofit Organization “Agency of Atmospheric Technologies” Moscow Russia State research center on Space Hydrometeorology PLANETA Moscow Russia

On the basis of a three-dimensional non stationary model of a convective cloud with detailed description of dynamic, thermodynamic and microphysical processes, numerical experiments were conducted to study the formation of parameters of convective clouds under unstable stratification of the atmosphere. Numerical experiments have been carried out to study the formation of convective processes in the atmosphere. The thermo hydrodynamic parameters in the zone of a thunderstorm cloud are determined, and regions with a vortex motion of air are identified. The main flows feeding the convective cloud in the mature stage are determined. Due to the means of visualization, the areas of formation and growth of precipitation particles are identified. In a three-dimensional form, the interaction of dynamic and thermodynamic processes is analyzed. The interaction of fields is manifested in the form of deformation of fields of thermodynamic parameters under the influence of dynamic processes. Trajectories of air streams around a cloud and the trajectories of drops in a cloud are determined. The results of numerical experiments confirm that dynamic processes significantly influence the formation of fields of thermodynamic parameters in the cloud, which also determine the course of microphysical processes and the nature of the growth of precipitation particles.

关键词： Numerical 3D Modeling Convective Processes in the Atmosphere Thermodynamic Parameters Microstructural Parameters velocity Field of Air Flow Particles Trajectories

Simulation of Gamma-Ray and Neutron Spectrometers for Microsatellite Missions

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Journal of Geoscience and Environment Protection 2018年第8期6卷 105-132页

作者： Masayuki Naito Nobuyuki Hasebe Junya Ishii José A.Matias-Lopes valery v.Dmitrenko Christian Wohler Kyeong Ja Kim School of Advanced Science and Engineering Waseda UniversityTokyoJapan Research Institute for Science and Engineering Waseda UniversityTokyoJapan Department of Physics University of CoimbraCoimbraPortugal National Research Nuclear University MEPhI MoscowRussia Image Analysis Group Dortmund University of TechnologyDortmundGermany Korea Institute of Gescience and Mineral Resources DaejeonSouth Korea

Microsatellites have recently opened windows of frequent and low cost missions for planetary exploration. The performance of gamma-ray and neutron spectrometers on future microsatellite missions is simulated to assess the possibility of observation of hydrogen and major elements, given their concentration on the observation target. The measured elemental abundance will provide important geological constraints, and some of them may serve as space resources. Four different types of target bodies with various hydrogen concentrations in the range of 0 - 20,000 ppm are assumed as target compositions;Earth’s core, C-type, S-type and Martian meteorites. Gamma-ray and neutron emission rates show unique footprints that are related to the different elemental compositions. The starting point is the solid angle subtended between observation target and spectrometers that allow estimating the gamma-ray and neutron count rates emitted by the celestial bodies. In this work, three types of gamma-ray detectors;high-purity germanium (HPGe), CeBr3 and LaBr3(Ce), a neutron spectrometer combining a lithium glass scintillator with a boron loaded plastic scintillator and a dual mode spectrometer Cs2LiYCl6(Ce) (CLYC) are simulated, focusing on their observation backgrounds as a model case for microsatellite based measurements. The background count level of both gamma-ray (except for the LaBr3 detector) and neutron count rates was negligible under these particular conditions. The gamma-ray detectors were compared by the figure of merit, which was determined by their efficiency and energy resolution. It was found that each detector has unique advantages. The HPGe detector has the highest figure of merit due to its excellent energy resolution, whereas the CLYC detector is low in weight and power consumption due to its dual sensitivity to gamma-ray and neutron. The CeBr3 detector is an intermediate choice. The neutron count rates are calculated separately in three energy ranges, i.e. , thermal

关键词： Gamma-Ray Spectrometer Neutron Spectrometer Microsatellite.High Purity Germanium CeBr3 LaBr3(Ce) CLYC

Regulating the Nuclear Reactor through Changes of the Fraction of Delayed Neutrons: Theoretical Probabilities

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Journal of Modern Physics 2010年第6期1卷 379-384页

作者： Dmitry v. Filippov Leonid I. Urutskoev valery I. Rachkov Olga I. Gadzaova Larion A. Lebedev 不详

In recent years а significant number of both theoretical and experimental works devoted to the influence of external electromagnetic fields and ionization on the probability of beta decays have been published. The present work investigates the feasibility of using this physical effect as the main mechanism for controlling the reactor. In this paper a system of equations is written and studied that allows one to describe the work of a nuclear reactor in the case where the probability of beta decay and, therefore, the fraction of delayed neu-trons is a function of time. It is shown that in the case of a constant fraction of delayed neutrons, the pro-posed system of equations is identical to the known system. As can be seen from analysis of a solution of the new system of equations for the proposed method of reactor control, acceleration by instantaneous neutrons is impossible even theoretically.

关键词： Fraction of Delayed Neutrons Bound-State Beta-Decay Kinetic Equation

Electronic and Transport Properties of Carbon Nanotubes with Impurities and Structure Disorder

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Journal of Physical Science and Application 2012年第7期2卷 224-232页

作者： valery Egorushkin Natalia Melnikova Nadezhda Bobenko Alexander Ponomarev Institute of Strength Physics and Materials Science of SB RAS Tomsk 634021 Russia v.D. Kuznetsov Siberian Physical Technical Institute of Tomsk State University Tomsk 634050 Russia

Electron relaxation time and density of states near the Fermi level were calculated for ＂dirty＂ carbon nanotubes taking into account multiple elastic electrons scattering on impurities and structural inhomogeneities of a short-range order type. A possible explanation of low-temperature behavior of density of states and electrical conductivity depending on defect structure, impurities and chirality is presented.

关键词： Nanomaterials electrical properties electron transport theory carbon nanotubes.

Carbon Composites for the Immobilization of Long-Lived Radio-Nuclides for the Purpose Their Disposal and Transmutation, Part 1

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Journal of Chemistry and Chemical Engineering 2014年第2期8卷 128-138页

作者： Murat K. Abdulakhatov Sergey Bartenev Nikolay Firsin Mikhail Goikhman valery Guselnikov Yury Novikov valery Romanovski Yury Sazanov Mikhail Zykov Decontamination Department National Research Centre "Kurchatov Institute " B. P. Konstantinov Petersburg Nuclear PhysicsInstitute Leningrad Region 188300 Russia Applied Radiochemistry Department V: G. Khlopin Radium Institute Saint-Peterburg 194021 Russia Laboratory for Synthesis of Polymeric Nanomaterials and Compositions for Optical Media Institute of MacromolecularCompounds Saint-Peterburg 199004 Russia

There is presented the review of publications connecting with creation of matrices for the immobilization of long-lived radionuclides and radioactive waste for storage and disposal, as well as for the transmutation. This paper substantiates the practicability and feasibility of obtaining the carbon matrces by carbonization of imidoderivatives.

关键词： Long-lived radio-nuclides RAW (radioactive waste) immobilization transmutation.

Change in the Pore Structure of Carbon-Carbon Composites during Successive Stages of High-Pressure Impregnation and Heat Treatment

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Journal of Chemistry and Chemical Engineering 2012年第12期6卷 1056-1060页

作者： Ekaterina v. Koganl Yury M. volfkovich Artem P. Malakho valery v. Kulakov Anatoly M. Kenigfest valentin E. Sosenkin Chemistry Department Moscow State University Moscow 119991 Russia Frumkin Institute of Physical Chemistry and Electrochemistry Russian Academy of Science Moscow 119071 Russia OAO Rubin Aircraft Corporation Balashikha 143900 Russia

Pore structure of C/C （Carbon-Carbon） composite after several stages of pitch impregnation under the high pressure and heat treatment was investigated by means of low temperature nitrogen adsorption and the standard contact porosimetry. Total pore volume, pore size distribution and specific surface area were calculated for samples of composite after several successive stages of treatment. The radius of pores presented in the material changes from 1 nm to 90 tam. Total pore volume and specific surface area both decrease after successive stages of pitch impregnation under the pressure, whereas heat treatment up to 1,750 ℃ and 2,000 ℃ leads to creation of some porous space and pore volume expansion. The bulk porosity of C/C composite comes down from 33.7% to 13.7% after the serial stages of treatment and the specific surface area is reduced by half compared to the initial material.

关键词： Carbon-carbon composite pore structure total pore volume specific surface area high-pressure impregnation heattreatment.

Reversible hydrogenation restores defected graphene to graphene

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Science China Chemistry 2021年第6期64卷 1047-1056页

作者： Lin Jiang Pauline MGvan Deursen Hadi Arjmandi-Tash Liubov ABelyaeva Haoyuan Qi Jiao He vincent Kofman Longfei Wu valery Muravev Ute Kaiser Harold Linnartz Emiel JMHensen Jan PHofmann Grégory FSchneider Leiden Institute of Chemistry Leiden UniversityEinsteinweg 552333CC LeidenThe Netherlands Central Facility for Electron Microscopy Electron Microscopy Group of Materials ScienceUlm UniversityAlbert-Einstein-Allee 11Ulm 89081Germany Laboratory for Astrophysics Leiden ObservatoryLeiden UniversityNiels Bohrweg 22333 CA LeidenThe Netherlands Laboratory for Inorganic Materials and Catalysis Department of Chemical Engineering and ChemistryEindhoven University of TechnologyP.O.Box 5135600 MB EindhovenThe Netherlands Center for Advancing Electronics Dresden(cfaed)and Faculty of Chemistry and Food Chemistry Technical University of Dresden010069 DresdenGermany

Graphene as a two-dimensional material is prone to hydrocarbon contaminations,which can significantly alter its intrinsic electrical ***,we implement a facile hydrogenation-dehydrogenation strategy to remove hydrocarbon contaminations and preserve the excellent transport properties of monolayer *** electron microscopy we quantitatively characterized the improved cleanness of hydrogenated graphene compared to untreated *** situ spectroscopic investigations revealed that the hydrogenation treatment promoted the adsorption of water at the graphene surface,resulting in a protective layer against the re-deposition of hydrocarbon ***,the further dehydrogenation of hydrogenated graphene rendered a more pristine-like basal plane with improved carrier mobility compared to untreated pristine *** findings provide a practical post-growth cleaning protocol for graphene with maintained surface cleanness and lattice integrity to systematically carry a range of surface chemistry in the form of a well-performing and reproducible transistor.

关键词： graphene reversible hydrogenation surface cleanness in situ spectroscopy transistors

Psychosocial Factors and the Risk of Type 2 Diabetes Mellitus in Women Population based Epidemiological Study

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Journal of Geriatric Medicine 2020年第2期2卷 1-10页

作者： valery Gafarov Dmitriy Panov Elena Gromova Igor Gagulin Almira Gafarova Institute of Internal and Preventive Medicine-branch of Institute of Cytology and Genetics SB RAS NovosibirskRussian Federation Collaborative laboratory of Cardiovascular Diseases Epidemiology NovosibirskRussian Federation

Our aim was to study the effect of depression and social support on the risk of type 2 diabetes in female population aged 25-64 in Russia/*** the screening surveys random representative samples of women aged 25-64 years were examined in 1994 and *** assessment was performed using the MONICA-MOPSY *** support was measured using the Berkman-Sim *** 1994 to 2018 in a cohort of women new-onset cases of diabetes mellitus were *** risk of T2DM in persons with depression was 1.844(pvariables,the risk decreased by 6%but remained significantly significant(pvel of social relations showed a significant effect on the risk of diabetes mellitus,including the multivariate model adjusted for the social gradient(HR=1.833,pve effect of education in diabetes *** incidence of T2D was higher in the group of manual labor and in *** and low social support increase the risk of T2DM by 80%.The frequencies of T2DM are determined by the social gradient and are associated with the role conflict“family-work”.

关键词： Depression Social support Diabetes Female population Risk

Natural isothiocyanates of the genus Capparis as potential agonists of apoptosis and antitumor drugs

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World Journal of Pharmacology 2023年第4期12卷 35-52页

作者： Lumír Hanuš Tuvia Naor Tatyana Gloriozova valery M Dembitsky Institute for Drug Research School of PharmacyFaculty of MedicineHebrew UniversityEin Kerem CampusJerusalem 91120Israel Food Chemistry KibbutzYotvata 8882000Israel Department of Bioinformatics Institute of Biomedical ChemistryMoscow 119121Russia Centre for Applied Research and Innovation Lethbridge CollegeLethbridge AB T1K 1L6Canada

BACKGROUND Using gas chromatography-mass spectrometry(GC/MS)analysis,we examined the composition of volatile components present in the yellow and green fruits,seeds,and jam of the scrambling shrub Capparis cartilaginea(***).These plant samples were collected from Kibbutz Yotvata in *** all the tested samples,isothiocyanates were *** the PASS program,we ascertained the biological activity of these isothiocyanates present in the Capparis *** study results highlighted that all isothiocyanates could potentially act as apoptosis agonists,making them strong candidates for antitumor *** information holds significant value for the fields of medicinal chemistry,pharmacology,and practical *** To investigate the volatile components present in the yellow and green fruits,seeds,and jam of the *** shrub using GC/MS analysis,to detect isothiocyanates in all the analyzed plant samples,and to assess the biological activity of these isothiocyanates utilizing the PASS *** We utilized two primary methods to analyze the volatile compounds present in the yellow and green fruits,seeds,and jams of the ***,native to *** identified biologically active isothiocyanates in these *** anticipated biological activities were determined using the PASS program,with the most dominant activities being apoptosis agonist,anticarcinogenic,and antineoplastic specifically for genitourinary *** Fruits,seeds,and jams containing isothiocyanates,which exhibit antineoplastic and anticarcinogenic activities,could be suggested for cancer prevention and *** isothiocyanates,with therapeutic potential in this realm,could be recommended as potent anticancer agents in practical medicine following clinical *** The discovery that isothiocyanates exhibit potent antineoplastic and anticarcinogenic activities was ***,certain isothiocyanates demonstrated antifu

关键词： Capparis cartilaginea Fruits Seeds Isothiocyanates Apoptosis Anticancer