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Journal of Computational Mathematics 2009年第2期27卷 360-387页

作者： Reinhold Schneider Thorsten Rohwedder alexey Neelov Johannes Blauert Institute for Mathematics Technical University BerlinStraβe des 17.Juni 13510623 BerlinGermany Institute of Physics University of BaselKlingelbergstrasse 824056 BaselSwitzerland Institute for Mathematics Technical University BerlinStraβe des 17. Juni 13510623 BerlinGermany

In this article, we analyse three related preconditioned steepest descent algorithms, which are partially popular in Hartree-Fock and kohn-Sham theory as well as invariant subspace computations, from the viewpoint of minimization of the corresponding functionals, constrained by orthogonality conditions. We exploit the geometry of the admissible manifold, i.e., the invariance with respect to unitary transformations, to reformulate the problem on the Grassmann manifold as the admissible set. We then prove asymptotical linear convergence of the algorithms under the condition that the Hessian of the corresponding Lagrangian is elliptic on the tangent space of the Grassmann manifold at the minimizer.

关键词： Eigenvalue computation Grassmann manifolds Optimization Orthogonalityconstraints Hartree-Fock theory Density functional theory PINVIT

Accurate and efficient band-gap predictions for metal halide perovskites at finite temperature

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npj Computational Materials 2022年第1期8卷 2267-2279页

作者： Haiyuan Wang alexey Tal Thomas Bischoff Patrick Gono Alfredo Pasquarello Chaire de Simulationàl’Echelle Atomique(CSEA) Ecole Polytechnique Fédérale de Lausanne(EPFL)LausanneCH-1015Switzerland

We develop a computationally efficient scheme to accurately determine finite-temperature band gaps for metal halide perovskites belonging to the class ABX_(3)(A=Rb,Cs;B=Ge,Sn,Pb;and X=F,Cl,Br,I).First,an initial estimate of the band gap is provided for the ideal crystalline structure through the use of a range-separated hybrid functional,in which the parameters are determined non-empirically from the electron density and the high-frequency dielectric ***,we consider two kinds of band-gap corrections to account for spin-orbit coupling and thermal vibrations including zero-point *** particular,the latter effect is accounted for through the special displacement method,which consists in using a single distorted configuration obtained from the vibrational frequencies and eigenmodes,thereby avoiding lengthy molecular *** sequential consideration of both corrections systematically improves the band gaps,reaching a mean absolute error of 0.17 eV with respect to experimental *** computational efficiency of our scheme stems from the fact that only a single calculation at the hybrid-functional level is required and that it is sufficient to evaluate the corrections at the semilocal level of *** scheme is thus convenient for the screening of large databases of metal halide perovskites,including large-size systems.

关键词： theory. perovskite halide

Synaptic mechanisms of cadmium neurotoxicity

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Neural Regeneration Research 2021年第9期16卷 1762-1763页

作者： Andrei N.Tsentsevitsky alexey M.Petrov Laboratory of Biophysics of Synaptic Processes Kazan Institute of Biochemistry and BiophysicsFederal Research Center“Kazan Scientific Center of RAS”2/31 Lobachevsky StreetBox 30Kazan420111Russia University 49 Butlerova StreetKazan420012Russia

Cadmium(Cd) is a toxic heavy metal ubiquitously distributed in the environment(water, air, food, smoke) with extreme ability to accumulate in the human body due to its delayed clearance(half-life time 15–30 years).

关键词： cadmium extreme accumulate

Uncertainty of Climate Response to Natural and Anthropogenic Forcings Due to Different Land Use Scenarios

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Advances in Atmospheric Sciences 2011年第5期28卷 1215-1232页

作者： alexey V.ELISEEV Igor I.MOkHOV A. M. Obukhov Institute of Atmospheric Physics Russian Academy of Sciences3 Pyzhevsky 119017 Moscow Russia

The *** Institute of Atmospheric Physics,Russian Academy of Sciences （IAP RAS） climate model （CM） of intermediate complexity is extended by a spatially explicit terrestrial carbon cycle *** experiments with the IAP RAS CM are performed forced by the reconstructions of anthropogenic and natural forcings for the 16th to the 20th centuries and by combined SRES （Special Report on Emission Scenarios） A2-LUH （Land Use Harmonization） anthropogenic scenarios for the 21st ***,the impact of uncertainty in land-use scenarios on results of simulations with a coupled climate-carbon cycle model is *** simulations of the model realistically reproduced historical changes in carbon cycle *** the IAP RAS CM,climate warming reproduced in the 20th and 21st centuries enhanced terrestrial net primary production but terrestrial carbon uptake was suppressed due to an overcompensating increase in soil *** year 2100,the simulations the model forced by different land use scenarios diverged markedly,by about 70 Pg （C） in terms of biomass and soil carbon stock but they differed only by about 10 ppmv in terms of atmospheric carbon dioxide content.

关键词： terrestrial carbon cycle climate model anthropogenic scenarios uncertainty in projections

Modified Biot Elastic Coefficients in Poroelastic Solid

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Journal of Earth Science 2024年第4期35卷 1397-1401页

作者： Chun Yang Yun Wang alexey Stovas Liheng Wang School of Geophysics and Information Technology China University of GeosciencesBeijing100083China Department of Geoscience and Petroleum Norwegian University of Science and TechnologyTrondheim 7031Norway key Laboratory of Shale Gas and Geoengineering Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China

0 INTRODUCTION Sedimentary rocks predominantly consist of porous solids saturated with fluids,the kinematic and dynamic characteristics of which are described through poroelasticity theory(Biot,1956a,b,1941).The wave propagation in fluid-saturated po-rous rocks obtains extensive attention owing to its relevance in diverse fields,such as ocean acoustics,exploration geophysics,and soil dynamics(Yang et al.,2023a;Xie et al.,2022).

关键词： saturated Elastic a,b

The anti-inflammatory astrocyte revealed:the role of the microbiome in shaping brain defences

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Signal Transduction and Targeted Therapy 2021年第5期6卷 1404-1405页

作者： Alexei Verkhratsky Peter Illes Yong Tang alexey Semyanov Faculty of Biology Medicine and HealthThe University of ManchesterManchesterUK Achucarro Center for Neuroscience IKERBASQUEBasque Foundation for Science48011 BilbaoSpain&Department of NeurosciencesUniversity of the Basque Country UPV/EHU and CIBERNEDLeioaSpain Sechenov First Moscow State Medical University MoscowRussia School of Acupuncture and Tuina and International Collaborative Centre on Big Science Plan for Purinergic Signalling Chengdu University of Traditional Chinese MedicineChengduChina Rudolf Boehm Institute for Pharmacology and Toxicology University of LeipzigLeipzigGermany Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry Russian Academy of SciencesMoscow117997Russia Faculty of Biology Moscow State UniversityMoscowRussia

The paper,published recently in Nature by the group of Francisco Quintana,1 describes the anti-inflammatory astrocytes,activity of which is tuned by the microbiotome and meningeal natural killer(Nk)*** are a sub-type of neuroglia responsible for homoeostasis and defence of the nervous *** reactions of neuroglial cells in various neurological disorders have been identified and characterised in the end of the 19th century;in particular hypertrophy of astrocytes was recognised as a frequent morbid change accompanying diseases of the central nervous system(CNS).

关键词： inflammatory stasis killer

Upper Mantle Density Heterogeneity in the European-Anatolian Tethys Belt

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Acta Geologica Sinica(English Edition) 2021年第S1期95卷 9-10页

作者： alexey SHULGIN Irina M.ARTEMIEVA CEED University of OsloNorway School of Earth Sciences China University of GeosciencesWuhanChina Marine Geodynamics GEOMAR Helmholtz Center for Ocean ResearchKielGermany Department of Geophysics Stanford UniversityCAUSA

We present a new model for the density structure of the lithosphere mantle(LM)in the region that extends from the Atlantic coast of Eurasia to the Ural mountains and from northern Africa and Arabia to the Arctic shelf... 详细信息

关键词： Upper mountains mantle

Silica-based nanoarchitecture for an optimal combination of photothermal and chemodynamic therapy functions of Cu2–xS cores with red emitting carbon dots

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Frontiers of Chemical Science and Engineering 2023年第12期17卷 2144-2155页

作者： alexey Stepanov Svetlana Fedorenko kirill kholin Irek Nizameev alexey Dovzhenko Rustem Zairov Tatiana Gerasimova Alexandra Voloshina Anna Lyubina Guzel Sibgatullina Dmitry Samigullin Asiya Mustafina Arbuzov Institute of Organic and Physical Chemistry FRC Kazan Scientific Center of RASKazan 420088Russia Department of Physics Kazan National Research Technological UniversityKazan 420015Russia Department of Nanotechnology in Electronics Kazan National Research Technical University named after A.N.Tupolev-KAIKazan 420111Russia kazan(Volga region)Federal University Kazan 420008Russia kazan Institute of Biochemistry and Biophysics FRC Kazan Scientific Center of RASKazan 420111Russia

This study introduces multifunctional silica nanoparticles that exhibit both high photothermal and chemodynamic therapeutic activities,in addition to *** activity of the silica nanoparticles is derived from their plasmonic properties,which are a result of infusing the silica nanoparticles with multiple Cu2-xS *** infusion process is facilitated by a recoating of the silica nanoparticles with a cationic *** key factors that enable the internal incorporation of the Cu2-xS cores and the external deposition of red-emitting carbon dots are *** Cu2-xS cores within the silica nanoparticles exhibit both self-boosting generation of reactive oxygen species and high photothermal conversion efficacy,which are essential for photothermal and chemodynamic *** silica nanoparticles’small size(no more than 70 nm)and high colloidal stability are prerequisites for their cell *** internalization of the red-emitting silica nanoparticles within cells is visualized using fluorescence microscopy *** chemodynamic activity of the silica nanoparticles is associated with their dark cytotoxicity,and the mechanisms of cell death are evaluated using an apoptotic *** photothermal activity of the silica nanoparticles is demonstrated by significant cell death under near-infrared(1064 nm)irradiation.

关键词： copper sulfide nanoparticles chemodynamic therapy photothermal therapy carbon dots silica nanoparticles

A Global Perspective on Crustal Structure and Evolution based on A New Crustal Classification

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Acta Geologica Sinica(English Edition) 2021年第S1期95卷 48-50页

作者： Irina M.ARTEMIEVA alexey SHULGIN School of Earth Sciences China University of GeosciencesWuhan 430074China Marine Geodynamics GEOMAR Helmholtz Center for Ocean ResearchKielGermany Department of Geophysics Stanford UniversityCAUSA CEED University of OsloNorway

knowledge of the crustal structure is the key for understanding physical and chemical conditions of its formation and later modification by geodynamic *** has long been recognized that crustal structure is controlled by tectonic settings,and that the crustal thickness is one of the most important parameters that reflects the geodynamic origin of the crust.A long tectonic life of continental crust leads to its significant reworking by plate tectonics processes and crust-mantle interaction,which include mechanical extension.

关键词： crustal delamination granitization basin subsidence orogenic processes continental rifting hotspots continental shelves failed oceans oceanic crust

The ecosystem of Lake kenon:past and present(Transbaikal 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.TSYBEkMITOVA Evgenia P.GORLACHEVA Balzhit B.BAZAROVA 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 by a combination of natural and anthropogenic factors. We have estimated the effects of a complex of factors on the condition of the abiotic environment and on specific biological components in the lake ecosystem. Change in biogenic load has caused an increase in the role of phytoplankton in the general balance of organic matter during the high-water period. Charophytes are the main dominants of bottom vegetation. Anthropogenic load has caused a decrease in both 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-hydrocarbonate-chloride calcium-sodic-magnesium in character. S（Y44 content is twice as much as the maximum permissible 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 combined heat and power plant operation.

关键词： water reservoir-cooler of combined heat and power plant (CHP) hydrochemistry ichthyofauna biodiversity the chemical elements