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Expansion of Juniperus sibirica *** a response to climate change and associated effect on mountain tundra vegetation in the Northern Urals

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Journal of Mountain Science 2020年第10期17卷 2339-2353页

作者： andrey a.grigoriev Yulia V.SHALAUMOVA Olga V.EROKHINA Svetlana Yu.SOKOVNINA Elizaveta I.VATOLINA Martin WILMKING Institute of Plant and Animal Ecology UB RAS Laboratory of Geoinformation TechnologyEkaterinburgRussia Institute of Industrial Ecology UB RAS Laboratory of Mathematical Modeling in Ecology and MedicineEkaterinburgRussia Institute of Plant and Animal Ecology UB RAS Laboratory of Vegetation and Mycobiota BiodiversityEkaterinburgRussia Institute of Plant and Animal Ecology UB RAS Laboratory of Dynamics of Arctic EcosystemsLabytnangiRussia Department of Forest Taxation and Forest Management Institute of Forest and Nature ManagementUral state Forest Engineering UniversityEkaterinburgRussia Institute for Botany and Landscape Ecology Greifswald UniversityGreifswaldGermany

Shrub expansion into arctic and alpine tundra is one of the prominent vegetation changes currently *** studied the expansion of shrub vegetation into high elevation tundra in the Kvarkush Range of the Northern Ural mountains,*** structure analysis of the dominant shrub Juniperus sibirica *** to support ongoing upslope advance of shrubs,a process particularly active in the second half of the 20 th *** found a close connection between the expansion of shrub vegetation and the general change in climatic conditions of the cold season(months with mean airtemperature below 0°Сfrom November to March).In general,the greatest influence on the distribution of *** is exerted by the climate conditions of the beginning(November-January)and the end(March)of the cold *** increasing elevation,the correlation coefficients between the establishment of *** shrubs and the precipitation of the beginning of the cold season increased,and reached maximum values at the top elevation level of the study ***,the upwards shift of *** into typical mountain tundra does not lead to changes in the ecological structure of vegetation at this stage,but simply a decrease in the area of mountain tundra.

关键词： Juniperus sibirica Expansion Tundra Vegetation Plant communities Climate changes Northern Ural mountains

Climate change evidence in tree growth and stand productivity at the upper treeline ecotone in the Polar Ural Mountains

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Forest Ecosystems 2020年第1期7卷 76-91页

作者： Nadezhda M.Devi Vladimir V.Kukarskih Аrina A.Galimova Valeriy S.Mazepa andrey a.grigoriev Institute of Plant and Animal Ecology Ural BranchRussian Academy of Sciences8 Marta202/3Ekaterinburg 620144Russia

Background:Recent warming is affecting species composition and species areal distribution of many ***,although most treeline studies have estimated the rates of forest expansion into tundra,still little is known about the long-term dynamic of stand productivity at the forest-tundra ***,we make use of tree-ring data from 350 larch(Larix sibirica Ledeb.)and spruce(Picea obovata Ledeb.)sampled along the singular altitudinal treeline ecotone at the Polar Urals to assess the dynamic of stand establishment and productivity,and link the results with meteorological observations to identify the main environmental ***:The analysis of stand instalment indicated that more than 90%of the living trees appeared after *** this period,the stand became denser and moved 50m upward,while in recent decades the trees of both species grew *** maximum afforestation occurred in the last decades of the twentieth century,and the large number of encountered saplings indicates that the forest is still *** upward shift coincided with a slight increase of May-August and nearly doubling of September-April precipitation while the increase in growth matched with an early growth season warming(June+0.27°C per decade since 1901).This increase in radial growth combined with the stand densification led to a 6-90 times increase of biomass since ***:Tree-ring based twentieth century reconstruction at the treeline ecotone shows an ongoing forest densification and expansion accompanied by an increased *** changes are driven by climate change mechanism,whereby the leading factors are the significant increase in May-June temperatures and precipitation during the dormant *** of phytomass accumulation mechanisms within treeline ecotone is valuable for improving our understanding of carbon dynamics and the overall climate balance in current treeline ecosystems and for predicting how these will be altered by global ch

关键词： Polar Urals Treeline Productivity Climate change Radial growth Recruitment Larch Spruce

等离子体技术制备具有亚微米颗粒结构的球化W-Cu伪合金微粉

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Transactions of Nonferrous Metals Society of China 2024年第2期34卷 592-603页

作者： A.V.SAMOKHIN N.V.ALEKSEEV A.A.DOROFEEV A.A.FADEEV M.A.SINAYSKIY I.D.ZAVERTIAEV Y.V.grigoriev Institute of Metallurgy and Materials Science Russian Academy of SciencesMoscow 119334Leninsky prospect 49Russian Federal Scientific Research Center“Crystallography and Photonics” Russian Academy of SciencesMoscow 119334Leninsky prospect 59Russian

采用复杂多级方法研究并证实制备具有亚微米/纳米级内部结构的球形W-Cu复合微粉的可能性。首先,采用等离子体化学合成法制备具有核壳结构的W-Cu纳米粉末(W核及Cu壳)。然后,将W-Cu纳米粉末与蔗糖的水悬浮液进行喷雾干燥,形成25~63μm的微... 详细信息

采用复杂多级方法研究并证实制备具有亚微米/纳米级内部结构的球形W-Cu复合微粉的可能性。首先,采用等离子体化学合成法制备具有核壳结构的W-Cu纳米粉末(W核及Cu壳)。然后,将W-Cu纳米粉末与蔗糖的水悬浮液进行喷雾干燥,形成25~63μm的微粒,收率为50%。最后,用热等离子体射流处理由纳米粉末组成的微粒,形成致密的球形W-Cu颗粒。成品粉末的球化度为90%~95%,体积密度为8.1 g/cm^(3),流动性约为12 s/50 g,杂质中O、C和H的含量(质量分数)分别为0.7%、0.02%~0.2%和0.03%~0.05%。

关键词： W-Cu复合材料等离子体化学合成造粒等离子体球化纳米颗粒微粒微粉

Elucidating elusive quaternary selenide EuCeCuSe3:Synthesis,crystal structure,properties and theoretical studies

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Journal of Rare Earths 2024年第1期42卷 163-171,I0006页

作者： Maxim V.grigoriev Anna V.Ruseikina Maxim S.Molokeev Vladimir A.Chernyshev Aleksandr S.Aleksandrovsky Alexander S.Krylov Svetlana N.Krylova Nikolai P.Shestakov Dmitriy A.Velikanov Alexander A.Garmonov Alexey V.Matigorov Evgeny A.Ostapchuk Thomas Schleid Damir A.Safin Laboratory of Theory and Optimization of Chemical and Technological Processes University of TyumenVolodarskogo Str.6625003TyumenRussian Federation Kirensky Institute of Physics Federal Research Center KSC SB RASAkademgorodok 50 Bld.38660036KrasnoyarskRussian Federation Department of Physics Far Eastern State Transport UniversitySerysheva Str.47680021KrasnoyarskRussian Federation Institute of Natural Sciences and Mathematics Ural Federal University Named After the First President of Russia B.N.YeltsinMira Str.19620002EkaterinburgRussian Federation Department of Photonics and Laser Technology Siberian Federal UniversitySvobodnii Ave.79660079KrasnoyarskRussian Federation Institute of Physics and Technology University of TyumenVolodarskogo Str.6625003 TyumenRussian Federation Institute for Inorganic Chemistry University of StuttgartPfaffenwaldring 55D-70569StuttgartGermany Scientific and Educational and Innovation Center for Chemical and Pharmaceutical Technologies Ural Federal University named after the First President of Russia B.N.YeltsinMira Str.19620002 EkaterinburgRussian Federation University of Tyumen Volodarskogo Str.6625003TyumenRussian Federation

We report on the novel heterometallic quaternary selenide EuCeCuSe3,the fabrication of which has been a challenge until this *** structure of the reported selenide was elucidated from the powder X-ray diffraction data,which revealed the formation of EuCeCuSe3with excellent yield(96.7%)accompanied with a minor fraction of CeSe2(3.3%),and was best solved in orthorhombic space group Pnma with the BaLaCuS3structural ***,the crystal structure of the title compound completes the row of the heterometallic quaternary selenides EuRECuSe3(RE=La,Pr,Nd,Sm,Eu,Gd,Tb,Dy,Ho,Er,Tm,Yb,Lu,Y),of which the cerium-based derivative exclusively belongs to the BaLaCuS3structural *** distortion of the CuSe4polyhedron was compared for the whole series of EuRECuSe3compounds using theτ4-descriptor for four coordinated ions,which revealed the highest degree of distortion for the Ce3+-containing selenide,followed by the La3+-based ***,the crystallographic and geometrical parameters of the reported selenide were discussed in comparison to the Ce3+-based sulfides SrCeCuS3and *** initio calculations of the crystal structure,a phonon spectrum and elastic constants for the crystal of EuCeCuSe3were also *** types and wavenumbers of fundame ntal modes were determined and the involvement of ions participating in the phonon modes was *** experimental IR spectrum of the reported selenide was interpreted and found to be in agreement with the calculated *** experimental direct band gap of EuCeCuSe3was measured to be 1.36 eV that is consistent with the concept of its origin due to interband transitions between orbitals emerging mainly from 4f(valence band)and 5d(conduction band)levels of the Eu2+*** dependence of the Young’s modulus on the direction demonstrates the anisotropy of the elastic properties,while the Vickers hardness for EuCeCuSe3was calculated to be 5.2 ***,the title compound is paramagnetic above 4 K.

关键词： Quaternary selenide Synthesis Crystal structure Ab initio calculations Magnetic measurements Spectroscopy

Acoustic emission characterization of sliding wear under condition of direct and inverse transformations in lowtemperature degradation aged Y-TZP and Y-TZP-Al_2O_3

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Friction 2018年第3期6卷 323-340页

作者： Nikolai L SAVCHENKO andrey V FILIPPOV Sergei Yu TARASOV andrey I DMITRIEV Evgeny V SHILKO Aleksandr S grigoriev Institute of Strength Physics and Materials Science SB RAS National Research Tomsk Polytechnic University National Research Tomsk State University

In this research, results of the investigation of the sliding friction and wear of yttria-stabilized tetragonal zirconia polycrystalline(Y-TZP) and Y-TZP-Al_2O_3 samples preliminarily subjected to low-temperature degradation are reported. The investigation was carried out using a pin-on-disk tribometer with simultaneous recording of acoustic emission(AE) and vibration acceleration. The sliding wear process was found to be determined by dynamic direct and inverse Y-TZP transformations detected by monoclinic and tetragonal X-ray diffraction peak ratios. The AE signals generated under direct and inverse transformations can be used to characterize wear and friction mechanisms as well as direct and inversed sliding-induced phase transformations. The AE signal energy grows with the friction coefficient and the inverse transformation degree. Reduction of the AE signal energy indicates establishing the mild wear stage caused by effective stress-induced direct martensitic transformation. The AE signal median frequency increases in the case of lower friction. Numerical studies of wear subsurface fracture under conditions of stress-induced martensitic transformation were used to elucidate the role played by the phase transformation in Y-TZP and Y-TZP-Al_2O_3. Martensitic transformation in Y-TZP was described with use of the non-associated dilatant plasticity model. Simulation results particularly show that increase in the value of dilatancy coefficient from 0 to 0.2 is accompanied by 25%-30% reduce in characteristic length and penetration depth of sliding-induced subsurface cracks. As shown the AE may be an effective tool for in-situ monitoring the subsurface wear of materials experiencing both direct and inverse transformations.

关键词： zirconia transformation toughening low-temperature degradation friction acoustic emission numerical modeling movable cellular automata method

Prediction and Optimization of System Quality and Risks on the Base of Modelling Processes

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American Journal of Operations Research 2013年第1期3卷 217-244页

作者： andrey Kostogryzov Leonid grigoriev George Nistratov andrey Nistratov Vladimir Krylov Gubkin Russian State University of Oil and Gas Moscow Russia Institute of Informatic Problems of the Russian Academy of Sciences Moscow Russia Research Institute of Applied Mathematics and Certification Moscow Russia Scientific&Technical Center “NAOPRO” Moscow Russia

The paper is concerned with the development and application of the original probability models and supporting them software tools to predict and optimize quality and risks for complex systems. The examples demonstrate possibilities to use modeling results from different application spheres and to go in making decision “from a pragmatical filtration of information to generation of the proved ideas and effective decisions”.

关键词： Analysis Model Quality Prediction Reliability Risk Safety Software Tools System Engineering

Influence of Small-Size Contaminations on Thin Film Structural Properties

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Chinese Physics Letters 2019年第3期36卷 82-85页

作者： F.V.grigoriev V.B.Sulimov Jinlong Zhang Xinbin Cheng Zhanshan Wang A.V.Tikhonravov Research Computing Center M.V.Lomonosov Moscow State University MOE Key Laboratory of Advanced Micro-Structured Materials Institute of Precision Optical Engineering School of Physics Science and EngineeringTongji University IFSA Collaborative Innovation Center Shanghai Jiao Tong University

An approach for studying the influence of nano-particles on the structural properties of deposited thin films is proposed. It is based on the molecular dynamic modeling of the deposition process in the presence of contaminating nano-particles. The nano-particle is assumed to be immobile and its interaction with film atoms is described by a spherically symmetric potential. The approach is applied to the investigation of properties of silicon dioxide films. Visualization tools are used to investigate the porosity associated with nano-particles. The structure of the film near the nano-particle is studied using the radial distribution function. It is found that fluctuations of film density near the nano-particles are essentially different in the cases of low-energy and high-energy deposition processes.

关键词： Influence Small-Size Properties

多年冻土区低层建筑地下室土基的解冻计算(英文)

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黑龙江大学工程学报 2014年第3期5卷 206-214页

作者： Terenty A.Kornilov Igor I.Rozhin Ekaterina A.Kononova Dmitry a.grigoriev Ayyna N.Danilova 东北联邦大学工程技术学院俄罗斯科学院西伯利亚分院石油和天然气研究所

对多年冻土区低层建筑地下室的解冻可通过数学建模的方法研究。该模型考虑了空气温度的变化、太阳总辐射、地表反照率以及一年中大气和地球表面之间的热传递系数的变化。建筑尺寸影响的研究,是基于基座面板的热阻和热条件土壤解冻动力... 详细信息

对多年冻土区低层建筑地下室的解冻可通过数学建模的方法研究。该模型考虑了空气温度的变化、太阳总辐射、地表反照率以及一年中大气和地球表面之间的热传递系数的变化。建筑尺寸影响的研究,是基于基座面板的热阻和热条件土壤解冻动力学计算实验进行的。比较评估的计算融化深度结果显示,现有的解冻深度的标准,大大低估了和不依赖于基座面板的热阻。此外,该标准不考虑初始土壤热状况和大气温度的年际变化。

关键词：地基低层建筑多年冻土和土壤条件计算实验

Positional Information Storage in Sequence Patterns

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Computational Molecular Bioscience 2013年第2期3卷 18-26页

作者： Alexey A. Shadrin Andrei grigoriev Dmitri V. Parkhomchuk Biology Department Center for Computational and Integrative Biology Rutgers University Camden USA Fachbereich Mathematik und Informatik Freie Universitat Berlin Berlin Germany Institut für Medizinische Genetik und Humangenetik der Charité—Universitatsmedizin Berlin Berlin Germany

We build a model of storage of well-defined positional information in probabilistic sequence patterns. Once a pattern is defined, it is possible to judge the effect of any mutation in it. We show that the frequency of beneficial mutations can be high in general and the same mutation can be either advantageous or deleterious depending on the pattern’s context. The model allows to treat positional information as a physical quantity, formulate its conservation law and to model its continuous evolution in a whole genome, with meaningful applications of basic physical principles such as optimal efficiency and channel capacity. A plausible example of optimal solution analytically describes phase transitions-like behavior. The model shows that, in principle, it is possible to store error-free information on sequences with arbitrary low conservation. The described theoretical framework allows one to approach from novel general perspectives such long-standing paradoxes as excessive junk DNA in large genomes or the corresponding G- and C-values paradoxes. We also expect it to have an effect on a number of fundamental concepts in population genetics including the neutral theory, cost-of-selection dilemma, error catastrophe and others.

关键词： Information Theory Sequence Pattern Genetic Information Conservation Typical Set