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Molecular Dynamics Simulations of Perovskites: The Effect of Potential Function Representation on Equilibrium Structural Properties

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Open Journal of Physical Chemistry 2015年第4期5卷 110-121页

作者： Kholmirzo T. Kholmurodov Sagille A. Ibragimova Pavel P. Gladishev Anatoly V. Vannikov Alexey R. Tameev tatyana yu. zelenyak Frank Laboratory of Neutron Physics JINR Dubna Russia Dubna International University Dubna Russia A.N. Frumkin Institute of Physical Chemistry and Electrochemistry Russian Academy of Sciences Moscow Russia

The perovskites with general formula ABX3 have been widely used as for materials with their unique properties (ferroelectric, piezoelectric, dielectric, catalytic and so on). Hybrid organolead halide perovskites are a class of semiconductors with ABX3 (X = Cl, Br, and I) structures consisting of lead cations in 6-fold coordination (B site), surrounded by an octahedron of halide anions (X site, face centered) together with the organic components in 12-fold cub octahedral coordination. These hybrid perovskites have a direct band gap, a large absorption coefficient as well as high charge carrier mobility that represent a very attractive characteristic of cost-effective solar cells. Basically, these crystals are inorganic solids of CaTiO3 type held together by bonds that are either ionic or partially ionic and partially covalent. In spite of the partially covalent character of the Ti-O bond, the system is modeled by a two-body central force interatomic potential (the form of the Vashishta and Rahman interatomic potential), which has been used successfully for many materials with a perovskite structure. In the present work using molecular dynamics (MD) simulation method we investigate the dynamical and structural behavior of CaTiO3 perovskite at normal pressure and temperature conditions. The MD calculations were performed on a system of 16,000 particles (3200Ca + 3200Ti + 96,00O), initially in an orthorhombic-Pbnm structure. The orthorhombic MD box had edges Lx = 53.4 Å, Ly = 53.4 Å and Lz = 61.12 Å, which provided a density matching the experimental value of ρ = 4 g/cm3. Starting with this structure and using proposed interatomic potentials the MD system stabilizes at room temperature in its initial configuration. The aim of the present study to explore the effect of potential function representations on structural equilibrium properties for the perovskite models including hybrid halide ones outlined above. Concerning the perovskite equilibrium state we

关键词： Perovskites Halides Potential Functions Structural Properties MD Simulations

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Endoparasites of the Siberian tiger(Panthera tigris altaica)

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Integrative Zoology 2018年第5期13卷 507-516页

作者： tatyana V.MOSKVINA Michail yu.SCHELKANOV Mariya A.BEGUN Far Eastern Federal University VladivostokPrimorsky KraiRussia Federal Scientific Center of Terrestrial Biodiversity of Eastern Asia Far Eastern Branch of Russian Academy of SciencesVladivostokPrimorsky KraiRussia

There have been few reports on the diversity and prevalence of parasitic fauna of the endangered Siberian tiger,which inhabits the territory of the Russian Far *** present review attempts to summarize the information about the parasitic fauna of wild Siberian tigers,which includes 15 helminths and 3 protozoan *** most prevalent parasitic species was found to be Toxocara cati,followed by Toxascaris *** commonly recorded Platyhelminth species is Paragonimus westermani,which causes a lethal infection of the lung parenchyma in Siberian ***,the information about infections by this fluke in the Siberian tigers is scarce,although *** infections pose a serious health hazard to tiger *** nematodes Aelurostrongylus abstrusus and Thominx aerophilus are found in Siberian tigers with an occurrence rate of 2.3%and 19%,*** information on the parasitic infestations of captive populations of Siberian tigers is also presented along with the sources of infection and hazards for the wild tiger populations in their natural environment.

关键词： helminths infection parasites protozoan Siberian tiger

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Nucleation of methane hydrate and ice in emulsions of water in crude oils and decane under non-isothermal conditions

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Chinese Journal of Chemical Engineering 2019年第3期27卷 668-676页

作者： Andrey S. Stoporev Lidiya I. Svarovskaya Larisa A. Strelets Lubov’ K. Altunina Galina V. Villevald Tamara D. Karpova tatyana V. Rodionova Andrey yu. Manakov Nikolaev Institute of Inorganic Chemistry SB RAS Novosibirsk State University Institute of Petroleum Chemistry

Achievable supercooling for the formation of methane hydrate from water emulsions was studied in seven different crude oils and in decane. The experiments were performed under constant rate cooling from + 20 to-15 °C and a pressure of methane of 12 MPa. It was demonstrated that the shapes and positions of the resulting survival curves depend on the density, viscosity and dispersive power of oil samples used in the experiments, as well as on the degree of oil oxidation. In addition, results of the experiments on ice freezing under the same emulsions are presented. The results obtained in the work allowed us to discuss the possibility and features of primary and secondary nucleation of the hydrate and ice in the systems under consideration.

关键词： Methane hydrate Crude oil Oil dispersive system Nucleation

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Morpho-Histological Analysis of Direct Shoot Organogenesis Induced in Flower Buds Cultures of <i>Allium altissimum</i>

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American Journal of Plant Sciences 2014年第13期5卷 2015-2022页

作者： tatyana V. Poluboyarova tatyana I. Novikova Galina yu. Vinogradova Elena V. Andronova Biotechnology Laboratory Central Siberian Botanical Garden of the Siberian Branch of the Russian Academy of Sciences Novosibirsk Russia Department of Embryology and Reproductive Biology Komarov Botanical Institute of the Russian Academy of Sciences St Petersburg Russia

The present work gives a detailed study of in vitro shoot organogenesis of the ornamental onion A. altissimum Regel from the buds of the middle layer of the inflorescences. The course of morphogenesis was examined by light and scanning electron microscopy. Histological observation revealed that during 3 - 5 days of culture on the BDS medium supplemented with 2.0 mg·L-1 of BA and 2.0 mg·L-1 of NAA the epidermal cells of the stamen filament in the area of its fusion with the tepal became competent and dedifferentiated. Originally the organogenesis involved several initial epidermal cells. The formation of meristematic centers was observed from day 3 to day 14. The apical shoot meristems and leaf primordia in a roller shape formed from day 14 to day 28 of culture on the same media. The further development of vegetative shoots and formation of the bulblets were observed when the explants were stimulated by triapenthenol (2.0 mg·L-1).

关键词： Allium altissimum Direct Shoot Organogenesis Regeneration Tissue Culture

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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.Misyu.a 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

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Does ADS 9346 have a low-mass companion?

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Research in Astronomy and Astrophysics 2021年第11期21卷 202-212页

作者： Olga V.Kiyaeva Maxim yu.Khovritchev Agrippina M.Kulikova Natalya V.Narizhnaya tatyana A.Vasilyeva Arina A.Apetyan Central Astronomical Observatory Russian Academy of Sciences65/1 Pulkovskoye ChausseeSt.Petersburg196140Russia

Based on the photographic and CCD observations of the relative motion of the A and B components of the binary system ADS 9346 obtained with the 26-inch refractor of Pulkovo Observatory during 1979–2019,we discover an invisible companion associated with star *** of the ephemerides with the positional and spectroscopic observations allowed us to calculate the preliminary orbit of the photocenter(P=15 yr).The minimal mass of the companion is approximately 0.13 *** existence of the invisible low-mass companion is implied by the IR-excess based on IRAS *** confirm this,additional observations of the radial velocity near the periastron need to be carried out.

关键词： (stars:)binaries:visual stars:low-mass stars:individual(ADS 9346)

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Synergistic effect of combination of surfactant and oxide powder on enhancement of gas hydrates nucleation

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Journal of Energy Chemistry 2017年第4期26卷 808-814页

作者： Anatoliy N.Nesterov Aleksey M.Reshetnikov Andrey yu.Manakov tatyana P.Adamova Institute of Earth’s Cryosphere SB RAS Malygina str.86Tyumen 625026Russian Federation Tyu.en State University Volodarskogo Str.6Tyumen 625003Russian Federation Tyu.en Industrial University Volodarskogo Str.38Tyumen 625000Russian Federation Nikolaev Institute of Inorganic Chemistry SB RAS Lavrentieva ave.3Novosibirsk 630090Russian Federation Novosibirsk State University Pirogova Str.2Novosibirsk 630090Russian Federation

In the present work we studied the induction periods of hydrate formation of natural gas in pure water, aqueous solutions of surfactants, and in the presence of surfactant together with aluminum oxide nanopowder, the activity of which as hydrate formation inducer was studied previously. Sodium dodecyl sulfate（SDS） or neonol AF-9-12 were used as the surfactants. It was demonstrated that the addition of either surfactants or aluminum oxide powder under our experimental conditions causes a decrease in the induction period of hydrate formation from;05 min for pure water to 30–35 min for water with additives. In the case of the simultaneous presence of surfactants and aluminum oxide powder in the system, induction period decreased to;0 min. So, the synergistic effect of the combination of surfactant and oxide powder on gas hydrate nucleation was demonstrated. Possible reasons of this effect have been discussed.

关键词： Gas hydrate Hydrate formation Nucleation Induction period Surfactant Nanopowder

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Geochemical reasons for high vulnerability of northern taiga ecosystems on hard gypsum outcrops

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Chinese Journal Of Geochemistry 2006年第B8期25卷 170-170页

作者： tatyana yu. Tuyu.ina Institute of Geography Russian Science Academy Moscow Russia

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Influence of chlorpyrifos oxon on the development and progression of Alzheimer’s disease in amyloid precursor protein transgenic mice

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Neuroimmunology and Neuroinflammation 2015年第1期2卷 31-42页

作者： Jin yu.Hong Zhu Aruna Bhat Hanaa El-Sayed tatyana Gudz Sebastiano Gattoni-Celli Mark S.Kindy Departments of Regenerative Medicine and Cell Biology and Neurosciences Medical University of South CarolinaCharlestonSC 29425USA Research Service Ralph H.Johnson Veterans Affairs Medical CenterCharlestonSC 29425USA Department of Radiation Oncology Medical University of South CarolinaCharlestonSC 29425USA Department of Bioengineering Clemson UniversityClemsonSC 29634USA

Aim:Alzheimer’s disease(AD)is a devastating neurological disorder and the most common form of *** date,the cause of AD eludes us,but a number of hypotheses have been put forward to try and understand the mechanisms involved.A series of studies have indicated that environmental factors,such as pesticides,heavy metals,and others can contribute to the development and progression of *** on these data,we determined the impact of pesticides(chlorpyrifos oxon[CPO])on AD‑like pathogenesis in amyloid precursor protein(APP)transgenic ***:APP mice were treated at various times with low‑dose CPO(1 mg/kg/day),in utero(3‑week of gestation),during lactation(3‑week),or as young adults(continuous dosing).Results:Exposure to CPO at all times enhanced neuro‑inflammation and exacerbated oxidative stress in the brain prior to amyloid ***‑treated APP mice showed a decrease in memory and learning compared with untreated APP mice;furthermore,analyses of brain tissue sections and extracts showed an increase in Aβ levels and C‑terminal fragment‑βlevels,a decrease in soluble APPα(sAPPα)levels,and an increase in plaque *** addition,CPO‑treated APP transgenic mice showed a significant decrease in neurotrophic factor levels(nerve growth factor,brain‑derived neurotrophic factor,and neurotrophin‑3)compared to vehicle‑treated APP transgenic *** with galantamine attenuated the effects of CPO by reducing amyloidβlevels and amyloid ***:CPO accelerated and exacerbated the disease development and progression in the APP mice suggesting that pesticides may play a significant role in the pathogenesis of AD.

关键词： Amyloid beta Alzheimer’s disease amyloid cognition inflammation toxin

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Comparison of Debris Flow Characteristics Obtained by Using Video Materials and Modeling

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Open Journal of Geology 2019年第2期9卷 75-88页

作者： Viktoriia Antonovna Kurovskaia Dariia Pavlovna Sokolova Andrey Alekseevich Ostashov tatyana Alexandrovna Vinogradova Saint-Petersburg State University Saint-Petersburg Russia

Velocity of debris flow is one of the most important characteristics for the protective construction design. Since debris flows are rare events, and observations are conducted only on stations in Russia, Ukraine, Italy, Switzerland, USA, China, Japan and New Zealand, the velocity is calculated rather than measured. Nowadays, a large number of videos with passing debris flows have appeared on the Internet. Scientists can use such video materials to obtain qualitative and quantitative characteristics of the debris flow. Therefore, the aim of our research is an attempt to measure the debris flow velocity using video materials and compare the obtained results with the calculated values using various methods. The debris flow that came down in Firgen, Austria on August 4, 2012 was chosen as the object of our study. The video was carried out from several angles, so it was possible to select a section of the channel, through which we could measure the debris flows waves velocity. In addition, we calculated the velocities of waves by formulas adopted in the regulatory documents and compared with the measured by video values. During the video analysis, debris flow velocities at different sites were observed: minimum—7.2 m/s and maximum—10 m/s. The calculated values varied from 4.5 m/s to 11.4 m/s. Moreover, we applied model of the transport-shear process of debris flow formation developed by yu. B. Vinogradov. When we were comparing the obtained debris flow discharges with results from Austrian colleagues, we found out that the values were similar to each other. However, internal scatter in the model changed from 151 to 190 m3/s, while in the report of Austrian colleagues the discharges were from 80 to 250 m3/s.

关键词： Debris Flow Velocity of Debris Flow Video Material of Debris Flow Empirical Formulas Modeling

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