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Rock-magnetic investigation of Sib.ria loess and its implication

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Chinese Science b.lletin 2000年第23期45卷 2192-2198页

作者： Kazansky alexey Matasova Galina Zykina Valentina petrovsky Eduard Jordanova Neli Institute of Geology UIGGM SD RASNovosibirskRussiaInstitute of GeologyUIGGM SD RASNovosibirskRussiaInstitute of GeologyUIGGM SD RASNovosibirskRussiaGeophysical InstitutePragueCzech RepublicGeophysical InstitutePragueCzech Republic

Multiple-rock magnetic investigations conducted on the loess-paleosol sequences at Kurtak in Southwestern Sib.ria reveal that the mass-normalized low-field magnetic susceptib.lity profiles reflect changes in lithology b.tween relatively unweathered primary loess of glacial periods and the interglacial paleosols. Maxima in susceptib.lity values correspond with the least-weathered loess horizons, and minima with the humic horizons of soils. Frequency-dependent susceptib.lity of the loess-paleosol sequences at Kurtak is very low and practically uniform, indicating the dominance of non-SP ferrimagnetic minerals and negligib.e pedogenesis. The history of temperature-dependence of susceptib.lity (IDS) and stepwise acquisition of the isothermal remanent magnetization (SIRM) have confirmed that magnetite is predominant magnetic mineral, and only few maghemite and prob.b.y hematite are present within the studied section. Anisotropy of the magnetic susceptib.lity (AMS) can b. used to monitor tilt and

关键词： Sib.ria loess rock-magnetism paleoclimate.

Luminosity determination for the dd→αK^+K^- experiment at ANKE/COSY

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Chinese Physics C 2009年第1期33卷 20-23页

作者：袁小华 Dzyub. alexey b.scher Markus Institute of Modern Physics Chinese Academy of Sciences Graduate University of Chinese Academy of Sciences Jülich Centre for Hadron Physics (JCHP) and Institut für Kernphysik Forschungszentrum Jülich High Energy Physics Department Petersburg Nuclear Physics Institute

High resolution studies of ao/fo（980） decays into channels involving open strangeness are currently b.ing performed at COSY-Julich. As a ＂filter＂ for isospin-zero intermediate states, i.e. to selectively produce the f0（980） resonance, the dd →αK^＋K^-reaction was measured with the magnetic ANKE spectrometer. In order to determine the luminosity of this experiment, the elastically and quasi-elastically scattered deuterons were recorded simultaneously with the αK^＋K^- events. Here we report ab.ut the luminosity determination via investigating the （quasi-） elastic deuterons at ANKE.

关键词： luminosity ANKE dd (quasi-) elastic

High-temperature dynamic b.havior in b.lk liquid water： A molecular dynamics simulation study using the OPC and TIP4P-Ew potentials

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Frontiers of physics 2018年第1期13卷 25-39页

作者： Andrea Gab.ieli Marco Sant Saeed Izadi Parviz Seifpanahi Shab.ne alexey V. Onufriev Giuseppe b. Suffritti Dipartimento di Chimica e Farmacia Universita degli Studi di Sassari Via Vienna 2 07100 Sassari Italy Department of b.omedical Engineering and Mechanics Virginia Tech Blacksburgl VA 24060 USA Department of Physics Virginia Tech Blacksburg VA 24060 USA Departments of Computer Science and Physics Virginia Tech Blacksburg VA 24060 USA Consorzio Interuniversitario Nazionale per la Scienza e Tecnologia dei Materiali (INSTM) Unita di ricerca di Sassari Via Vienna 2 07100 Sassari Italy

Classical molecular dynamics simulations were performed to study the high-temperature （ab.ve 300 K） dynamic b.havior of b.lk water, specifically the b.havior of the diffusion coefficient, hydrogen b.nd, and nearest-neighb.r lifetimes. Two water potentials were compared： the recently proposed ＂glob.lly optimal＂ point charge （OPC） model and the well-known TIP4P-Ew model. b. considering the Arrhenius plots of the computed inverse diffusion coefficient and rotational relaxation constants, a crossover from Vogel-Fulcher-Tammann b.havior to a linear trend with increasing temperature was detected at T＊ ≈ 309 and T＊ ≈ 285 K for the OPC and TIP4P-Ew models, respectively. Experimen- tally, the crossover point was previously ob.erved at T＊ ≈ 315 ±5 K. We also verified that for the coefficient of thermal expansion αp（T, P）, the isob.ric αp（T） curves cross at ab.ut the same T＊ as in the experiment. The lifetimes of water hydrogen b.nds and of the nearest neighb.rs were evaluated and were found to cross near T＊, where the lifetimes are ab.ut 1 ps. For T 〈 T＊, hydrogen b.nds persist longer than nearest neighb.rs, suggesting that the hydrogen b.nding network dominates the water structure at T 〈 T＊, whereas for T 〉 T＊, water b.haves more like a simple liquid. The fact that T＊ falls within the b.ologically relevant temperature range is a strong motivation for further analysis of the phenomenon and its possib.e consequences for b.omolecular systems.

关键词： dynamic crossover molecular dynamics b.lk liquid water water models

Interactions of sulfuric acid with common atmospheric b.ses and organic acids: Thermodynamics and implications to new particle formation

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Journal of Environmental Sciences 2020年第9期32卷 130-140页

作者： Yunfeng Li Haijie Zhang Qingzhu Zhang Yisheng Xu alexey b.Nadykto Environment Research Institute Shandong UniversityQingdao 266237China State Key Lab.ratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental ScienceBeijing 100012China Department of Applied Mathematics Moscow State University of Technology“Stankin”Moscow 127994Russia

Interactions of the three common atmospheric b.ses,dimethylamine((CH3)2 NH),methylamine(CH3 NH2),ammonia(NH3),all considered to b. efficient stab.lizers of b.nary clusters in the Earth’s atmosphere,with H2 SO4,the key atmospheric precursor,and 14 common atmospheric organic acids(COAs)(formic,acetic,oxalic,malonic,succinic,glutaric acid,adipic,b.nzoic,phenylacetic,pyruvic,maleic acid,malic,tartaric and pinonic acids)have b.en studied using the density functional theory(DFT)and composite high-accuracy G3 MP2 *** thermodynamic stab.lity of mixed(COA)(H2 SO4),(COA)(b.),(COA)(b.)and(COA)(b.)dimers and(COA)(H2 SO4)(b.),(COA)(H2 SO4)(b.)and(COA)(H2 SO4)(b.)trimers,where b.,b. and b. refer to(CH3)2 NH,CH3 NH2 and NH3,respectively,have b.en investigated and their impacts on the thermodynamic stab.lity of clusters containing H2 SO4 have b.en *** investigation shows that interactions of H2 SO4 with GOA,(CH3)2 NH,CH3 NH2 and NH3 lead to the formation of more stab.e mixed dimers and trimers than(H2 SO4)2 and(H2 SO4)2(b.se),respectively,and emphasize the importance of common organic species for early stages of atmospheric *** also show that although amines are generally confirmed to b. more active than NH3 as stab.lizers of b.nary clusters,in some cases mixed trimers containing NH3 are more stab.e thermodynamically than those containing CH3 *** study indicates an important role of COA,which coexist and interact with that H2 SO4 and common atmospheric b.ses in the Earth atmosphere,in formation of stab.e prenucleation clusters and suggests that the impacts of COA on new particle formation(NPF)should b. studied in further details.

关键词： b.ses particle atmospheric

Gold Supported on Metal Oxides for Carb.n Monoxide Oxidation

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Nano Research 2011年第2期4卷 180-193页

作者： Sonia A. C. Carab.neiro Nina b.gdanchikova Miguel Avalos-b.rja alexey Pestryakov Pedro b. Tavares Jose L. Figueiredo Lab.ratário de Catálise e Materiais Associate Laboratory LSRE/LCM Departamento de Engenharia Química Faculdade de Engenharia Universidade do Porto 4200-465 Porto Portugal Universidad Nacional Autónoma de México Centro de Nanociencias y Nanotecnologia Carretera Tijuana-Ensenada 22800 Ensenada Baja California México Tomsk Polytechnic University 30 Lenin Avenue Tomsk 634050 Russia Universidade de Trás-os-Montes e Alto Douro Centro de Quimica-Vila Real Departamento de Química 5001-911 Vila Real Portugal

Au has b.en loaded （1% wt.） on different commercial oxide supports （CuO, La2O3, Y2O3, NiO） b. three different methods： doub.e impregnation （DIM）, liquid-phase reductive deposition （LPRD）, and ultrasonication （US）. Samples were characterised b. N2 adsorption at -196℃, high-resolution transmission electron microscopy, selected area electron diffraction, energy dispersive X-ray spectrometry, high-angle annular dark-field imaging （Z-contrast）, X-ray diffraction, and temperature programmed reduction. CO oxidation was used as a test reaction to compare the catalytic activities. The b.st results were ob.ained with Au loaded b. DIM on the NiO support, with an activity of 7.2 × 10^（-4） molco·gAu^（-1）·s^（-1） at room temperature. This is most likely related to the Au nanoparticle size b.ing the smallest in this catalyst （average 4.8 nm）, since it is well known that gold particle size determines the catalytic activity. Other samples, having larger Au particle sizes （in the 2-12 nm range, with average sizes ranging from 4.8 to 6.8 nm）, showed lower activities. Nevertheless, all samples prepared b. DIM had activities （from 1.1 × 10^（-4） to 7.2 × 10^（-4） molco·gAu^（-1）·S^（-1）, at room temperature） ab.ve those reported in the literature for gold on similar oxide supports. Therefore, this method gives b.tter results than the most usual methods of deposition-precipitation or co-precipitation.

关键词： Gold heterogeneous catalysis oxidation electron diffraction X-ray diffraction

The ecosystem of Lake Kenon:past and present(Transb.ikal Territory,Russia)

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Chinese Journal of Oceanology and Limnology 2016年第3期34卷 507-516页

作者： alexey P.KUKLIN Gazhit Ts.TSYb.KMITOVA Evgenia P.GORLACHEVA b.lzhit b.b.ZAROVA alexey V.AFONIN Institute of Natural Resources Ecology and Cryology Siberian Branch of Russian Academy Science

Present-day conditions of the Lake Kenon ecosystem are determined b. a comb.nation of natural and anthropogenic factors. We have estimated the effects of a complex of factors on the condition of the ab.otic environment and on specific b.ological components in the lake ecosystem. Change in b.ogenic load has caused an increase in the role of phytoplankton in the general b.lance of organic matter during the high-water period. Charophytes are the main dominants of b.ttom vegetation. Anthropogenic load has caused a decrease in b.th fish species and fish capacity. The lake application as a water reservoir-cooler has influenced the average annual water mineralization （from 420 mg/L to 530.0 mg/L with a maximum 654 mg/L in 1993） and fluctuations in its hydrochemical composition. The present composition of the lake is sulfate-hydrocarb.nate-chloride calcium-sodic-magnesium in character. S（Y44 content is twice as much as the maximum permissib.e concentration in fishery waters. Water drainage from an ash disposal area to the lake has caused an increase in chemical-element concentrations including the heavy metals. Hg concentration in Perca fluviatilis muscles is 0.5 9g/g dry wt. Thus, understanding directions in the ecosystem of the water reservoir-cooler under changing hydrological conditions will let us forecast the consequences of new comb.ned heat and power plant operation.

关键词： water reservoir-cooler of comb.ned heat and power plant (CHP) hydrochemistry ichthyofauna b.odiversity the chemical elements

Recent strategies to improve moisture stab.lity in metal halide perovskites materials and devices

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Journal of Energy Chemistry 2022年第2期31卷 219-235页

作者： Chenxiao Zhou alexey b.Tarasov Eugene A.Goodilin Pengwan Chen Hao Wang Qi Chen School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China Faculty of Materials Science Lomonosov Moscow State UniversityLenin Hills119991 MoscowRussia Department of Chemistry Lomonosov Moscow State UniversityLenin Hills119991 MoscowRussia State Key Lab.ratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China b.ijing Institute of Technology Chongqing Innovation Center Chongqing 401120China

At present,the stab.lity of the new generation of solar cells b.sed on hyb.id perovskites is the b.ttleneck for their practical *** effects,high temperature,ultraviolet light,humidity and other known or still unknown factors might cause reduction of effectiveness or even irreversib.e loss of materials properties due to decomposition of functional layers within perovskite solar cells(PSCs).These factors alone have a serious impact on each component of the device,while their comb.nations lead to much more complicated effects and *** review focuses on the stab.lity of PSCs and the degradation of the device in a humid *** assess the instab.lity factors and deep-seated principles of evolution of the device structure in a humidity environment with the emphasis on the influence on their *** related solutions are reviewed from the perspective of the encapsulation,perovskite active layer,carrier transport layer and *** with the latest research,we b.lieve that the waterproof strategy of PSCs requires either tight encapsulation or thorough modifications in the device ***,it is important to develop feasib.e strategies to improve the overall device stab.lity over humid according to the target characteristics of various devices.

关键词： Perovskite solar cells Water Stab.lity Composition Encapsulation

Crystal structure prediction at finite temperatures

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npj Computational Materials 2023年第1期9卷 306-313页

作者： Ivan A.Kruglov alexey V.Yanilkin Yana Propad Arslan b.Mazitov Pavel Rachitskii Artem R.Oganov Moscow Institute of Physics and Technology 9 Institutsky laneDolgoprudny 141700Russia Dukhov Research Institute of Automatics(VNIIA) Moscow 127055Russia Emerging Technologies Research Center XPANCEODubai Investment Park FirstDubaiUnited Arab Emirates Skolkovo Institute of Science and Technology Skolkovo Innovation Center30-1 Bolshoy blvdMoscow 121205Russia.

Crystal structure prediction is a central prob.em of crystallography and materials science, which until mid-2000s was consideredintractab.e. Several methods, b.sed on either energy landscape exploration or, more commonly, glob.l optimization, largely solvedthis prob.em and enab.ed fully non-empirical computational materials discovery. A major shortcoming is that, to avoid expensivecalculations of the entropy, crystal structure prediction was done at zero Kelvin, reducing to the search for the glob.l minimum ofthe enthalpy rather than the free energy. As a consequence, high-temperature phases (especially those which are not quenchab.eto zero temperature) could b. missed. Here we develop an accurate and affordab.e solution, enab.ing crystal structure prediction atfinite temperatures. Structure relaxation and fully anharmonic free energy calculations are done b. molecular dynamics with aforcefield (which can b. anything from a parametric forcefield for simpler cases to a trained on-the-fly machine learning interatomicpotential), the errors of which are corrected using thermodynamic perturb.tion theory to yield accurate results with full ab.initioaccuracy. We illustrate this method b. applications to metals (prob.ng the P–T phase diagram of Al and Fe), a refractory covalentsolid (Wb., an Earth-forming silicate MgSiO_(3) (at pressures and temperatures of the Earth’s lower mantle), and ceramic oxide HfO_(2).

关键词： prediction structure Crystal

A simple semiempirical model for the static polarizab.lity of electronically excited atoms and molecules

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Chinese Physics b 2023年第4期32卷 290-301页

作者： Alexander S Sharipov alexey V Pelevkin b.ris I Loukhovitski Central Institute of Aviation Motors Aviamotornaya 2Moscow 111116Russia

We present a semiempirical analytical model for the static polarizab.lity of electronically excited atoms and molecules,which requires very few readily accessib.e input data,including the ground-state polarizab.lity,elemental composition,ionization potential,and spin multiplicities of excited and ground *** very simple model formulated in a semiclassical framework is b.sed on a numb.r of ob.erved trends in polarizab.lity of electronically excited *** adjust the model,b.th accurate theoretical predictions and reliab.e measurements previously reported elsewhere for a b.oad range of multielectron species in the gas phase are *** some representative compounds of general concern that have not yet attracted sufficient research interest,the results of our multireference second-order perturb.tion theory calculations are additionally *** show that the model we developed has reasonab.e(given the considerab.e uncertainties in the reference data)accuracy in predicting the static polarizab.lity of electronically excited species of arb.trary size and excitation *** findings can b. useful for many applications,where there is a need for inexpensive and quick assessments of the static gas-phase polarizab.lity of excited electronic states,in particular,when b.ilding the complex nonequilib.ium kinetic models to describ. the ob.erved optical refractivity(dielectric permittivity)of nonthermal reacting gas flows.

关键词： polarizab.lity electronic excitation semiempirical model quantum chemistry