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Temperature regime of mountain permafrost in the Russian Altai Mountains

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Journal of Mountain Science 2022年第1期19卷 33-45页

作者： Robert SYSOLYATIN sergei SERIKOV Mikhail ZHELEZNYAK Mark SHATZ Yana TIKHONRAVOVA Melnikov Permafrost Institute Yakutsk 677010Russia

This study presents the long-term temperature monitoring in the Russian Altai Mountains. In contrast to the Mongolian and Chinese parts, the modern temperature regime of the Russian Altai remains unclear. The complexity of a comprehensive understanding of permafrost conditions in the Russian Altai is related to the high dissection of the terrain, the paucity of the latest observational data, and the sparse population of permafrost areas. The general objective of this study is to determine the temperature regime on the surface,in the active layer, and in the zero annual amplitude(ZAA) layer, based on the known patterns of permafrost distribution in the region. Using automatic measuring equipment(loggers), we obtained information on the temperature of frozen and thawed ground within the altitudes from 1484 to 2879 m a. s. l. during the period from 2014 to *** array of 15 loggers determined the temperature regime of bare and vegetated areas within watersheds,slopes, and valleys. N-factor parameters and surface temperature are similar to those in the Mongolian Altai, but the mean annual ground temperature at the depth of 1 m has a wide range of fluctuations(more than 32℃) based on research results, and we allocated it into three groups based on altitudinal zonality. Snow cover has a strong influence on the temperature regime, but the determination of the fine-scale variability requires additional *** temperature regime during the observation period remained stable, but continued monitoring allows a more detailed assessment of the response to climatic changes.

关键词： Ground temperature Mountain permafrost Temperature monitoring Altai Mountain Climate change

Effect of salinity on seed germination, growth and ion content in dimorphic seeds of Salicornia europaea L. （Chenopodiaceae）

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Plant Diversity 2016年第4期38卷 183-189页

作者： Nikolai Orlovsky Ulbasyn Japakova Huifan Zhang sergei Volis The J. Blaustein Institutes for Desert Research Ben-Gurion University of the Negev POB 84990 Israel Scientific Center of Plant Production "Botanika" of Uzbek Academy of Sciences 2 F. Khodjaev Str.. 700143 Tashkent Uzbekistan Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204 China

The halophyte Salicornia europaea L. is a widely distributed salt-tolerant plant species that produces numerous dimorphic seeds. We studied germination and recovery in dimorphic seeds of Central Asian S. europaea under various salinity conditions. We also tested the effects of various salts on Na＋ and K＋ accumulation during plant development from germination to anthesis under greenhouse conditions. We found good germination （close to control） of large seeds under NaCl between 0.5 and 2%, Na2SO4 and 2NaCl ＋ KCl ＋ CaCl between 0.5 and 3%, and 2Na2SO4 ＋ K2SO4 -- MgSO4 between 0.5 and 5%. For the small seeds, we found stimulating effects of chloride salts （both pure and mixed） under 0.5-1% concentrations, and sulfate salts under 0.5-3%. Both types of seeds showed high germination recovery potential. Salt tolerance limits of the two seed types during germination and at the later stages of development were very similar （4-5%）. During plant growth the optimal concentrations of mixed chloride and sulfate salts ranged from 0.5 to 2%. The mechanisms of salt tolerance in the two seed types of S. europaea appear to differ, but complement each other, improving overall adaptation of this species to high salinity.

关键词： Dimorphic seeds Germination Salinity Recovery Ion content

Crystal-field levels of Nd3+ in a new langasite compound Nd3CrGe3Be2O14

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Journal of Rare Earths 2019年第11期37卷 1250-1254页

作者： sergei A.Klimin Boris V.Mill Marina N.Popova Institute of Spectroscopy Russian Academy of SciencesTroitskMoscow 108840Russia Faculty of Physics M.V.Lomonosov Moscow State UniversityMoscow 119991Russia

We report on the crystal-field(CF)levels of Nd^3+in Nd3CrGe3Be2O14,a representative of recently synthesized Be-containing *** are the first in the family to contain two magnetic subsystems,1 D chromium and Kagome-like rare-earth ***-resolution broad-band temperature-dependent spectra allow us to find all five CF Kramers doublets of the ground 4I9/2 CF multiplet and 38 levels of the excited 4I11/2,13/2,15/2,4F3/2,4F5/2+2H9/2,4F7/2+4S3/2 and 4F9/2 CF *** data form a basis for a future exploration of this interesting two-sublattice magnet with frustrated *** transitions between Kramers doublets of Nd^3+indicate magnetic activity of 1D-chromium chains at T<20 K.

关键词： Langasite Two magnetic subsystems High-resolution spectroscopy Crystal-field levels Magnetic correlations Rare earths

Off-the-shelf deep learning is not enough,and requires parsimony,Bayesianity,and causality

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npj Computational Materials 2021年第1期7卷 133-138页

作者： Rama K.Vasudevan Maxim Ziatdinov Lukas Vlcek sergei.V.Kalinin Center for Nanophase Materials Sciences Oak RidgeTN 37831USA Computational Sciences and Engineering Division Oak RidgeTN 37831USA Materials Science and Technology Division Oak Ridge National LaboratoryOak RidgeTN 37831USA Present address:Bayer St.LouisMO 63141USA

Deep neural networks(‘deep learning’)have emerged as a technology of choice to tackle problems in speech recognition,computer vision,finance,***,adoption of deep learning in physical domains brings substantial challenges stemming from the correlative nature of deep learning methods compared to the causal,hypothesis driven nature of modern *** argue that the broad adoption of Bayesian methods incorporating prior knowledge,development of solutions with incorporated physical constraints and parsimonious structural descriptors and generative models,and ultimately adoption of causal models,offers a path forward for fundamental and applied research.

关键词： learning enough finance

Effect of a weak magnetic field on ductile-brittle transition in micro-cutting of single-crystal calcium fluoride

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Journal of Materials Science & Technology 2022年第17期112卷 96-113页

作者： Yunfa Guo Yan Jin Lee Yu Zhang Anastassia Sorkin sergei Manzhos Hao Wang Department of Mechanical Engineering National University of Singapore9 Engineering Drive 1Singapore 117575Singapore School of Materials and Chemical Technology Tokyo Institute of TechnologyOokayama 2-12-1Meguro-kuTokyo 152-8552Japan

Magneto-plasticity occurs when a weak magnetic field alters material plasticity and offers a viable solution to enhance ductile-mode cutting of brittle *** study demonstrates the susceptibility of non-magnetic single-crystal calcium fluoride(CaF_(2))to the magneto-plastic *** influence of magneto-plasticity on CaF_(2) was confirmed in micro-deformation tests under a weak magnetic field of 20 *** surface pile-up effect was weakened by 10-15 nm along with an enlarged plastic zone and suppressed crack propagation under the influence of the magnetic ***-cutting tests along different crystal orientations on the(111)plane of CaF_(2) revealed an increase in the ductile-brittle transition of the machined surface with the aid of magneto-plasticity where the largest increase in ductile-brittle transition occurred along the[112]orientation from 512 nm to a range of 664-806 ***,the subsurface damage layer was concurrently thinner under magnetic *** anisotropic influence of the magnetic field relative to the single-crystal orientation and the cutting direction was also *** analytical model was derived to determine an orientation factor M that successfully describes the anisotropy while considering the single-crystal dislocation behaviour,material fracture toughness,and the orientation of the magnetic *** suggested theoretical mechanism of magneto-plasticity via formation of non-singlet electronic states in defected configurations was confirmed with density functional theory *** successful findings on the influence of a weak magnetic field on plasticity present an opportunity for the adoption of magnetic-assisted micro-cutting of non-magnetic materials.

关键词： Magneto-plasticity Weak magnetic field Brittle material Ductile-brittle transition Micro-cutting

A bridge for accelerating materials by design

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npj Computational Materials 2015年第1期1卷 56-66页

作者： Bobby G Sumpter Rama K Vasudevan Thomas Potok sergei V Kalinin Center for Nanophase Materials Sciences Oak Ridge National LaboratoryOak RidgeTNUSA Computer Science and Mathematics Division Oak Ridge National LaboratoryOak RidgeTNUSA Institute for Functional Imaging of Materials Oak Ridge National LaboratoryOak RidgeTNUSA Computer Science and Engineering Division Oak Ridge National LaboratoryOak RidgeTNUSA

Recent technical advances in the area of nanoscale imaging,spectroscopy and scattering/diffraction have led to unprecedented capabilities for investigating materials structural,dynamical and functional *** addition,recent advances in computational algorithms and computer capacities that are orders of magnitude larger/faster have enabled large-scale simulations of materials properties starting with nothing but the identity of the atomic species and the basic principles of quantum and statistical mechanics and *** with these advances,an explosion of high-resolution data has *** confluence of capabilities and rise of big data offer grand opportunities for advancing materials sciences but also introduce several *** this perspective,we identify challenges impeding progress towards advancing materials by design(e.g.,the design/discovery of materials with improved properties/performance),possible solutions and provide examples of scientific issues that can be addressed using a tightly integrated approach where theory and experiments are linked through big-deep data.

关键词： bridge starting materials

Siberian silkmoth outbreaks surpassed geoclimatic barrier in Siberian Mountains

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Journal of Mountain Science 2020年第8期17卷 1891-1900页

作者： KHARUK Viacheslav I. IM sergei T. SOLDATOV Vladimir V. Sukachev Institute of Forest Federal Scientific CenterRussian Academy of ScienceSiberian BranchAcademgorodok 50/28Krasnoyarsk660036 Russia Siberian Federal University Svobodny str.79Krasnoyarsk660041 Russia Reshetnev Siberian State University of Science and Technology Krasnoyarsky rabochy str.31Krasnoyarsk660014 Russia Russian Center of Forest Protection Academgorodok 50A/2Krasnoyarsk660036 Russia

Siberian silkmoth(SSM,Dendrolimus sibiricus Tschetv.)is the most important defoliator of Siberian pine(Pinus sibirica Du Tour)and fir(Abies sibirica Ledeb.)***-induced SSM outbreaks are one of the major driving factors of successions within the taiga *** is suggested that climate change impacted the SSM range and life *** analyzed the migration of alpine and northerly SSM outbreak boundaries in Siberia and the impact of the climate variables and topography on the outbreak *** used time-series scenes(multispectral data,and vegetation indexes EVI and NDII)in combination with field studies,climate variables,and GIS *** found that SSM outbreaks in the area of alpine boundary shifted about 370 m uphill since the mid of *** outbreak onset was promoted by increased dryness and active temperatures and decreased root zone moisture content in the spring-early summer *** terrain topography strongly affected SSM outbreak onset and ***,the outbreak was located at the middle elevations on the gentle concave southeastern slopes,which are the favorable insect habitats between *** the outbreak expanded uphill and downhill,to steeper slopes,and both concave and convex *** with elevation range expansion,SSM surpassed its northern historical outbreak boundary:the potential outbreaks’boundary moved about 300 km *** warming contributes to SSM migration into former outbreak free conifer stands located in highlands and at northern latitudes.

关键词： Insect outbreaks Remote sensing monitoring Insect ranges expansion Siberian silkmoth Forest health Conifer mortality

Alpine ecotone in the Siberian Mountains:vegetation response to warming

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Journal of Mountain Science 2021年第12期18卷 3099-3108页

作者： KHARUK Viacheslav I. IM sergei T. PETROV Il’ya A. Sukachev Institute of Forest Federal Scientific CenterRussian Academy of ScienceSiberian BranchAcademgorodok 50/28Krasnoyarsk 660036Russia Siberian Federal University Svobodny str.79Krasnoyarsk 660041Russia Reshetnev Siberian State University of Science and Technology Krasnoyarsky rabochy str.31Krasnoyarsk 660014Russia

Birch(Betula tortuosa)is one of the treeline forming species within the Siberian *** analysed the area dynamics of birch stands and the upslope climb of birch treeline based on the Landsat time series scenes and on-ground *** found that since the warming onset(1970th)birch area increased by 10%,birch stands and treeline boundary were moving upslope with a rate of 1.4 m/yr and 4.0 m/*** upslope shift correlated with air temperatures at the beginning(May-June)and the end(August-October)of the growth ***,no correlation was found between birch upslope migration and *** negatively influenced both birch area growth and birch upslope climb during spring,fall,and *** the windy habitats,birch,together with larch and Siberian pine,formed clusters(hedges)which mitigated the influence of adverse *** clusters are the adaptive pattern for trees’upslope climb within windward *** other adaptation to the harsh alpine ecotone habitat is non-leaf(bark)photosynthesis which supports tree ***,Betula tortuosa upslope climb depends on the wind impact and warming in spring and fall that extended growth *** ongoing warming and observed wind speed decrease on the background of sufficient precipitation,it is expected to further birch advance into alpine tundra in the Siberian Mountains.

关键词： Alpine biomes Treeline shift rate Treeline ecotone Siberian mountain forests Betula tortuosa Forest densification Tree clustering

Temperature monitoring from 2012 to 2019 in central part of Suntar-Khayat Ridge,Russia

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Journal of Mountain Science 2020年第10期17卷 2321-2338页

作者： Robert SYSOLYATIN sergei SERIKOV Mikhai Yana TIKHONRAVOVA Vladimir ZHIZHIN Maria ROJINA Melnikov Permafrost Institute Yakutsk 677010Russia

In recent decades,research of the Alps,Qinghai-Tibet Plateau,and Cordillera have made great progress in understanding the phenomenon of *** the most part,this has been made possible due to temperature ***,the permafrost parameters in an area of more than 2 million square km of the mountainous regions of northeast Asia,for the most part,remain a blank spot in the scientific *** to the lack and insufficiency of factual materials,in 2012 the *** Permafrost Institute began to take temperature measurements in the upper part of the permafrost in the central part of the VerkhoyanKolyma uplands,namely the Suntar-Khayat *** article describes the temperature characteristics of air,surface and rocks of the active layer in the range of heights from 850 to 1821 m,in various landscape and topographic *** the observation period from 2012 to 2019,we obtained information on temperatures in the soils of the active layer at depths of 1 m,3 m,4 m,and 5 m and also air and surface temperature *** availability of data on automated monitoring of rock temperatures in the active layer and the upper horizons of the layer of annual heat rotations made it possible to substantiate the most typical conditions of the temperature conditions of the permafrost zone of the characterized *** parameters of permafrost existence and development are in favorable *** is shown in the analysis of temperature data of air,surface and active *** temperatures in the active layer of annual heat rotations are most clearly represented at a depth of 1 ***,on the territory of the mountain regions of Eastern Siberia,there are no more such sites for monitoring the temperature regime of *** on the permafrost parameters in the region will allow us to begin the process of creating new models or checking existing forecasts and the distribution of the temperature *** will also make it possible to eval

关键词： Air temperature Ground temperature Climate change Mountain permafrost Active layer thickness