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Tree clusters migration into alpine tundra,Siberia

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Journal of Mountain Science 2022年第12期19卷 3426-3440页

作者： KHARUK Viacheslav I. petrov II'ya A. IM Sergei T. GOlYUKOV Alexey S. DVINSKAYA Maria l. SHUSHPANOV Alexander S. Sukacheu Institute of Forest Federal Scientific CenterRussian Academy of ScienceSiberian BranchAcademgorodok 50/28Krasnoyarsk 660036Russia Siberian Federal University Svobodny str.79Krasnoyarsk 660041Russia Reshetneu Siberian State University of Science and Technology Krasnoyarsky rabochy str.31Krasnoyarsk 66014Russia Tomsk State University Leninastr.36Tomsk 634050Russia

We hypothesize that in mountain windy habitat trees formed clusters(hedges)as adaptive structures for seedlings’rooting,survival,and tress’upslope migration.We studied hedges formed by Siberian pine(Pinus sibirica du Tour)and larch(larix sibirica ledeb.)within the treeline ecotone in southern Siberian Mountains,investigated hedges formation,evolution,habitat amelioration,and analyzed tree’s growth index(GI)dependence on the eco-climate variables(air temperature,precipitation,soil moisture,wind speed)and relief features(elevation,aspect,slope steepness,and terrain curvature).We conducted a ground survey,measured biometrical parameters of trees and hedges,determined species composition and tree physiognomy,soil types and nutrient contents,and sampled wood cores and applied dendrochronology for trees’GI analysis.With high-resolution satellite scenes for hedge detection and upslope migration,we found that winter winds and soil moisture are the main constraints of trees’settlement and growth.Hedge formation always links with wind-sheltered microtopography features(boulders,local depressions or felled trees).Once the first tree is established,a positive feedback is aroused that facilitates seedling rooting and in-hedge habitat amelioration.Trees form a streamlined dense“common crown”that mitigates adverse winter wind influence.Hedges always orient along the prevailing winds,and trees’uphill migration occurs by seedlings establishment within the leeward hedge side.Hedge growth facilitates soil formation and fertilization.The concentration of nutrients(K,P,N and S)within hedges exceeds the background by 1.5-5.5 times.Hedge extension leads to increased snow accumulation that mitigates the influence of desiccation and snow abrasion and mitigates seasonal water stress.In the extremely harsh windy habitat,inhedge trees present in mat,prostrate or krummholz forms.With warming,tree stems and even twigs turn upright.Notably that GI dependence on the wind speed is insignificant until prostrated trees get turning upright.Since th

关键词： Treeline Timberline Hedges Tree migration Siberian pine larch Tree growth Siberian mountain forests Wind stress Moisture stress

larch growth across thermal and moisture gradients in the Siberian Mountains

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Journal of Mountain Science 2023年第1期20卷 101-114页

作者： KHARUK Viacheslav I. petrov Il'ya A. GOlYUKOV Alexey S. DVINSKAYA Maria l. IM Sergei T. SHUSHPANOV Alexander S. Sukachev Institute of Forest Federal Scientific CenterRussian Academy of ScienceSiberian BranchAcademgorodok 50/28Krasnoyarsk660036Russia Siberian Federal University Svobodny str.79Krasnoyarsk660041Russia Reshetnev Siberian State University of Science and Technology Krasnoyarsky rabochy str.31Krasnoyarsk660014Russia Tomsk State University Lenina str.36Tomsk634050Russia

Climate-driven changes in the thermal and moisture regimes may variously influence different tree species growth and ranges.We hypothesize that drought resistant Siberian larch(larix sibirica ledeb.)and precipitation-sensitive Siberian pine(Pinus sibirica Du Tour)responded differently to climate change along the elevational thermal and precipitation gradients.We studied the influence of air temperature,precipitation,soil moisture,and atmospheric drought(indicated by the drought index SPEI)on larch and pine growth along the southward megaslope of the West Sayan Ridge.We found that since 2000 climate change resulted in increasing larch and pine radial growth index(GI)(c.1.5–3times)within treeline(2000–2300 m)and timberline(1900–2000 m)ecotones,i.***.within high precipitation zones.Within the forest-steppe ecotone(1100–1200 m)in which l.sibirica is the only species,larch GI stagnated or even decreased.The total forested area increased since 2000 up to+50%in the high elevations,whereas in the low elevations(ligible.Within treeline and timberline,trees’GI was stimulated by summer temperature.Meanwhile,temperature increase in early spring reduces GI due to living tissue activation followed by tissue damage by desiccation.Within forest-steppe,larch radial growth was mostly dependent on soil moisture.Warming shifted dependence on moisture to the early dates of the growing period.Acute droughts decreased GI within forest-steppe as well as within treeline,whereas the drought influence on both species within highlands was insignificant.Within forest-steppe seedlings establishment was poor,whereas it was successful within treeline and timberline.Current climate change leads to stagnation or even decrease in larix sibirica growth in the southern lowland habitat.In combination with poor seedlings establishment,reduced growth threatens the transformation of open lowland forests into forest-steppe and steppe communities.Meanwhile,in the highlands warming facilitated the growth of Siberian larch and pin

关键词： larch Siberian pine Climate influence on tree radial growth Mountain forests Treeline Timberline Foreststeppe Drought stress Moisture stress

Reaction Mechanism and Deactivation Modes of Heterogeneous Catalytic Systems

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催化学报 2011年第3期32卷 387-404页

作者： K.KUMBIlIEVA l.petrov Y.AlHAMED A.AlZAHRANI InstituteofCatalysis BulgarianAcademyofSciencesSolTaBulgaria SABICChairofCatalysis KingAbdulazizUniversityJeddahSaudiArabia

解决催化剂释放的问题在过程设计是必要的。做这，有催化剂释放的过程的动力学的各种各样的方面，和他们的不同机制，被讨论。催化剂释放不能经常被避免，但是它的机制上的更多的知识能帮助发现运动工具减少它的有害后果。当释放被焦炭... 详细信息

解决催化剂释放的问题在过程设计是必要的。做这，有催化剂释放的过程的动力学的各种各样的方面，和他们的不同机制，被讨论。催化剂释放不能经常被避免，但是它的机制上的更多的知识能帮助发现运动工具减少它的有害后果。当释放被焦炭引起时，焦炭先锋的产生是在释放动力学的决定的步。释放的不同类型被区分导致这个过程的不同进化。不一致的 coking 的现象能被连接到催化剂表面不一致。为有活跃地点的超过一种类型的催化剂的班，解释在释放模式为观察趋势被建议。为用工业尺寸的催化剂粒子的催化过程， intraparticle 散开抵抗的影响是重要的。分析证明为很多个过程，反应率的减少由于释放是在散开控制下面的更少。为某些反应机制，在那里存在在散开控制下面的进程的率在运动控制政体超过率的操作条件。一个重要问题是在催化剂释放期间的选择的变化。选择也可以减少或增加，并且在释放期间取决于反应机制。当没有散开抵抗时，变化更大。为乙烯氧化物生产的过程的在催化剂活动和选择的催化剂和它的影响的故意的毒害被讨论。

关键词：化学动力学催化高压化学燃烧

How to stabilize standard perovskite solar cells to withstand operating conditions under an ambient environment for more than 1000 hours using simple and universal encapsulation

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Journal of Energy Chemistry 2023年第3期78卷 246-252,I0008页

作者： Nikolai A.Belich Andrey A.petrov Pavel A.Ivlev Natalia N.Udalova Alla A.Pustovalova Eugene A.Goodilin Alexey B.Tarasov laboratory of New Materials for Solar Energetics Faculty of Materials ScienceLomonosov Moscow State University119991 MoscowRussia Department of Chemistry Lomonosov Moscow State University119991 MoscowRussia

We introduce a simple and universal scalable encapsulation strategy for perovskite solar cells based on thermal vacuum evaporation of MgF2or MoO3-xcapping layer followed by sealing the device with glass and UV-curable polymer.The proposed encapsulation method is beneficial to most of the other known encapsulation approaches being fully harmless to perovskite and transporting layers and processible at room temperature.Vacuum deposition of the capping layer promotes efficient removal of water,oxygen and organic solvent residuals from the device prior to sealing and could be easily performed using standard equipment for metal electrode deposition.The proposed strategy is transferrable to any lab-scale perovskite solar cell prototypes regardless of their geometry and architecture and results in excellent stability of the devices in ambient air and long operating conditions.Upon the 1000 hours stability test at ambient air(30%-60% RH),the cells preserved 92.9% of their initial efficiency on average under 1 Sun illumination at constant maximum power point tracking(MPPT,ISOS-l-1) and over 96% under sto rage in the dark(ISOS-D-1),thus evidencing for the high effectiveness of the proposed encapsulation approach.

关键词： Perovskite solar cells Halide perovskites Encapsulation High stability ISOS-l-1

具有不同活性中心的固体催化剂的失活模式(英文)

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催化学报 2011年第1期32卷 51-59页

作者： K.KUMBIlIEVA l.petrov Institute of Catalysis Bulgarian Academy of Sciences SABIC Chair in Catalysis King Abdulaziz University

An approach is suggested to distinguish different types of active sites responsible for different reactions on bifunctional catalysts.The model assumes a non-uniform vulnerability of active sites that depends on their location.Problems on the relationship between the dispersion of the active phase and selectivity are discussed.The effect of coke formation on the activity change of different sites is analyzed.

关键词：稳固的催化剂释放模式 bifunctional 催化剂活跃地点

Tree wave migration across an elevation gradient in the Altai Mountains,Siberia

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Journal of Mountain Science 2017年第3期14卷 442-452页

作者： Viacheslav I.KHARUK Sergei T.IM Maria l.DVINSKAYA Kenneth J.RANSON Il'ya A.petrov Sukachev Institute of Forest SB RAS KrasnoyarskRussia Siberian Federal University KrasnoyarskRussia M.F.Reshetnev Siberian State Aerospace University KrasnoyarskRussia NASA's Goddard Space Flight Center GreenbeltMarylandUSA

The phenomenon of tree waves(hedges and ribbons) formation within the alpine ecotone in Altai Mountains and its response to observed air temperature increase was considered. At the upper limit of tree growth Siberian pine(Pinus sibirica) forms hedges on windward slopes and ribbons on the leeward ones. Hedges were formed by prevailing winds and oriented along winds direction. Ribbons were formed by snow blowing and accumulating on the leeward slope and perpendicular to the prevailing winds, as well as to the elevation gradient. Hedges were always linked with microtopography features, whereas ribbons were not. Trees are migrating upward by waves and new ribbons and hedges are forming at or near tree line, whereas at lower elevations ribbons and hedges are being transformed into closed forests. Time series of high-resolution satellite scenes(from 1968 to 2010) indicated an upslope shift in the position ribbons averaged 155±26 m(or 3.7 m yr^(-1)) and crown closure increased(about 35%–90%). The hedges advance was limited by poor regeneration establishment and was negligible. Regeneration within the ribbon zone was approximately 2.5 times(5060 vs 2120 ha^(-1)) higherthen within the hedges zone. During the last four decades, Siberian pine in both hedges and ribbons strongly increased its growth increment, and recent tree growth rate for 50 year-old trees was about twice higher than those recorded for similarly-aged trees at the beginning of the 20^(th) century. Hedges and ribbons are phenomena that are widespread within the southern and northern Siberian Mountains.

关键词：带子森林篱笆西伯利亚的森林高山的 treeline 树波浪西伯利亚的松阿尔泰山山

NSVS 2569022:a peculiar binary among W UMa stars with extremely small mass ratios

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Research in Astronomy and Astrophysics 2018年第10期18卷 123-130页

作者： Diana P.Kjurkchieva Velimir A.Popov Nikola I.petrov Department of Physics and Astronomy Shumen University Institute of Astronomy and NAO Bulgarian Academy of Sciences

Photometric observations of the W UMa binary NSVS 2569022 are presented. The light curve solution reveals that both components are of F spectral type （temperatures T1 = T2 = 6100 K）. NSVS 2569022 undergoes a total eclipse of W subtype and the mass ratio is well-determined. Its extremely small value of only 0.077 implies that the target will probably experience instability and a possible merger. This value ranks NSVS 2569022 in sixth place among binaries with the smallest mass ratio. Based on an empirical relation of ＂period - total mass＂ for low mass-ratio binaries, we estimate the global parameters of NSVS 2569022： masses M1 = 1.17 M⊙ and M2 = 0.09 M⊙; radii R1 = 1.19 R⊙ and R2 = 0.38 R⊙; luminosities l1 = 1.73 l⊙ and l2 = 0.17l⊙. An analysis of the characteristics of binaries with extremely low-mass ratios is made. NSVS 2569022 turns out to be a peculiar binary among W UMa stars with extremely small mass ratios due to its unexpectedly small fill-out factor of only 0.014 （slightly overcontact configuration）.

关键词： binaries eclipsing - binaries close - stars fundamental parameters - stars individual（NSVS 2569022）

Warming hiatus-and evergreen conifers in Altay-Sayan Region,Siberia

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Journal of Mountain Science 2018年第12期15卷 2579-2589页

作者： Viacheslav I.KHARUK Sergei T.IM Il'ya A.petrov Sukachev Institute of Forest Federal Scientific CenterRussian Academy of ScienceSiberian BranchAcademgorodok 50/28Krasnoyarsk660036Russia Siberian Federal University Suobodny str.79Krasnoyarsk 660041Russia Reshetnev Siberian State University of Science and Technology Krasnoyarsky rabochy str.31Krasnoyarsk 660014Russia

"Warming hiatus" occurred in the AltaySayan Mountain Region, Siberia in c. 1997–2014. We analyzed evergreen conifer(EGC) stands area(satellite data) and trees(Siberian pine, Pinus sibirica Du Tour, Siberian fir, Abies sibirica ledeb.) growth increment(dendrochronology data) response to climate variables before and during the hiatus. During the hiatus, EGC area increased in the highlands(>1000 m)(+30%), whereas at low and middle elevations(l.) the EGC area decreased(-7%). The EGC area increase was observed on the rain-ward northwest slopes mainly. In highlands, EGC area increase mainly correlated with summer air temperature, whereas at low and middle elevations EGC area decrease correlated with drought index SPEI and vapor pressure deficit(VPD). EGC mortality(fir and Siberian pine) in lowland was caused by the synergy of water stress(inciting factor) and barkbeetle attacks(contributing factor). Tree growth increment(GI) dynamics differs with respect to elevation. At high elevation(1700 m) GI permanently increased since warming onset, whereas at the middle(900 m) and low elevations(450 m) GI increased until c. 1983 yr. with followed depression. That GI "breakpoint" occurred about a decade before hiatus onset. In spite of growth depression, during hiatus GI was higher than that in pre-warming period. At high elevation, GI positively responded to elevated June temperatures and negatively to moisture increase(precipitation, root zone moisture content, VPD, and SPEI). At low elevation GI negatively responded to June temperatures and positively to moisture increase. For both, low and high elevation, these patterns persisted throughout the study period(1967–2014). On the contrary, at middle elevations GI dependence on climate variables switch after breakpoint year(1983). Before breakpoint, June air temperature(positive correlation) and moisture(negative correlations) controlled GI. Further temperature increase leads GI depression and switched correlation signs to opposite(from positive to negative with tempe

关键词： Growth increment Warming hiatus Warming impact Conifer decline Tree growth Tree mortality Conifer mortality Water stress

颗粒内传质参数作为工具用于催化剂颗粒的设计(英文)

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催化学报 2012年第7期33卷 1166-1175页

作者： l. petrov M. DAOUS Y. AlHAMED A. Al-ZAHRANI Kh. MAXIMOV SABIC Chair in Catalysis Chemical and Materials Engineering Department Faculty of Engineering King Abdulaziz University PO Box 80204 Jeddah 21589 Kingdom of Saudi Arabia Institute of Catalysis Bulgarian Academy of Sciences Sofia 1113 Bulgaria

A chromatographic method and a dynamic Wicke-Kallenbach method (DMWK) were used to determine the diffusion characteristics of two industrial copper containing catalysts. The first catalyst was used in nitrobenzene hydrogenation to aniline and the second was used in a low temperature water-gas shift reaction. Experimental results show that application of these two methods leads to similar results. Experimental data obtained allow for monitoring changes in the texture of the catalyst grains and intraparticle diffusivity of gaseous reagents at different states of the catalyst activity and use, which can be used as criteria for designing optimal industrial catalyst pellets.

关键词： effective diffusion coefficient tortuosity copper catalyst pellet design