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Effects of site preparation methods on soil physical properties and outplanting success of coniferous seedlings in boreal forests

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Journal of Forestry Research 2024年第2期35卷 70-80页

作者： aleksey S.Ilintsev.Elena N.Nakv.sina Alexander P.Bogdanov Northern Research Institute of Forestry 13 Nikitova Str.Arkhangelsk 163062Russian Federation Department of Silv.culture and Forest Management Northern(Arctic)Federal University Named After M.V.LomonosovSevernoy Dviny Emb.17Arkhangelsk 163002Russian Federation

This study assessed the effect of patch scarification and mounding on the physical properties of the root layer and the success of tree planting in v.rious types of *** study was conducted on 12 forest sites in taiga forests of the European part of Russia.A total of 54 plots were set up to assess seedling surv.v.l;root collar diameter,height,and heigh increment were measured for 240 seedlings to assess *** the rooting layer,240 soil samples were taken to determine physical *** study showed that soil treatment methods had no effect on bulk density and total porosity in Cladina ***,reduced soil moisture was noted,particularly in mounds,resulting in increased *** Myrtillus sites,there were increased bulk density,reduced soil moisture,and total porosity in the *** treatment in Polytrichum sites resulted in reduced soil moisture and increased aeration *** the Myrtillus and Polytrichum sites,patch scarification had no effects on physical *** Polytrichum sites,surv.v.l rates,heights,and heigh increments of bareroot Norway spruce seedlings in mounds were higher than in patches;howev.r,the same did not apply to *** Cladina and Myrtillus sites,there was no difference in growth for bareroot and containerised seedlings with different soil *** conditions and soil types should be considered when applying different soil treatment methods to ensure high surv.v.l rates and successful seedling growth.

关键词： Boreal forests Mechanical site preparation Patch scarification Mounding Soil properties Containerised seedlings Bareroot seedlings

Porous Shish-Kebab Structure Prepared from Oriented UHMWPE Films by Processing in Supercritical CO_(2)

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Chinese Journal of Polymer Science 2024年第1期42卷 97-104,I0009页

作者： Sergey A.Lermontov.aleksey v.Maksimkin Nataliya A.Sipyagina Tarek Dayyoub Alena N.Malkov. Ev.eniy A.Kolesnikov.Elena A.Straumal Inna O.Gozhikov. Saidkhodzha G.Nematulloev.Dmitry v.Telyshev Institute of Physiologically Activ. Compounds of the Russian Academy of Sciences Chernogolovka 142432Russia Institute for Bionic Technologies and Engineering I.M.Sechenov First Moscow State Medical University(Sechenov University)Moscow 19991Russia National Univ.rsity of Science and Technology"MISIS"Moscow 119049 Russia Institute of Biomedical Systems National Research University of Electronic TechnologyZelenogradMoscow 124498Russia

For the first time, a highly crystalline porous shish-kebab structure with a high degree of crystallinity was obtained by using a combination of two methods for the formation of porous polymeric materials. A treatment procedure using supercritical carbon dioxide(sc CO_(2))was carried out for oriented ultrahigh molecular weight polyethylene(UHMWPE) films, which prov.ded special conditions for the crystallization of dissolv.d UHMWPE macromolecules on the surface of oriented UHMWPE crystals. The prepared porous materials were inv.stigated by scanning electron microscopy(SEM) and differential scanning calorimetry(DSC). The particularity of the obtained porous shish-kebab is the absence of the amorphous phase between lamellar crystals(kebabs). The obtained pores had an ov.l shape, and they were oriented in the orientation direction of the UHMWPE macromolecules. The pore size ranged from 0.05 μm to 4 μm. Controlling the conditions for the crystallization of the UHMWPE macromolecules using supercritical CO_(2) giv.s the possibility to control the size of both lamellar disks and pores formed.

关键词： UHMWPE Supercritical CO_(2) Porous shish-kebab structure

Exploring v.n der Waals materials with high anisotropy:geometrical and optical approaches

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Light(Science & Applications) 2024年第4期13卷 645-653页

作者： Aleksandr S.Slav.ch Georgy A.Ermolaev.Mikhail K.Tatmyshev.kiy Adilet N.Toksumakov.Olga G.Matv.ev. Dmitriy v.Grudinin Kirill v.v.ronin Arslan Mazitov.Konstantin v.Krav.sov.Alexander v.Syuy Dmitry M.Tsymbarenko Mikhail S.Mironov.Sergey M.Nov.kov.Iv.n Kruglov.Dav.t A.Ghazaryan Andrey A.v.shnev.y aleksey v.Arsenin v.lentyn S.v.lkov.Kostya S.Nov.selov Moscow Center for Adv.nced Studies Kulakova str.20Moscow 123592Russia. Emerging Technologies Research Center XPANCEOInternet CityEmmay TowerDubaiUnited Arab Emirates. Donostia International Physics Center(DIPC) Donostia/San-Sebastián 20018Spain. Institute of Materials Ecole Polytechnique Federale de Lausanne1015 LausanneSwitzerland. Department of Chemistry Lomonosov Moscow State UniversityMoscow 119991Russia. Laboratory of Adv.nced Functional Materials Yerevan State UniversityYerevan 0025Armenia. National Graphene Institute(NGI) University of ManchesterManchester M139PLUK. Department of Materials Science and Engineering National University of SingaporeSingapore 03-09 EASingapore. Institute for Functional Intelligent Materials National University of Singapore117544 SingaporeSingapore

The emergence of v.n der Waals(v.W)materials resulted in the discov.ry of their high optical,mechanical,and electronic anisotropic properties,immediately enabling countless nov.l phenomena and *** success inspired an intensiv. search for the highest possible anisotropic properties among v.W ***,the identification of the most promising among the huge family of v.W materials is a challenging quest requiring innov.tiv. ***,we suggest an easy-to-use method for such a surv.y based on the crystallographic geometrical perspectiv. of v.W materials followed by their optical *** our approach,we found As2S3 as a highly anisotropic v.W *** demonstrates high in-plane optical anisotropy that is~20%larger than for rutile and ov.r two times as large as calcite,high refractiv. index,and transparency in the v.sible range,ov.rcoming the century-long record set by *** these benefits,As2S3 opens a pathway towards nextgeneration nanophotonics as demonstrated by an ultrathin true zero-order quarter-wav. plate that combines classical and the Fabry–Pérot optical phase ***,our approach prov.des an effectiv. and easy-to-use method to find v.W materials with the utmost anisotropic properties.

关键词： anisotropy anisotropic high

Synthesis of Al2O3-SiO2-MgO ceramics with hierarchical porous structure

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Journal of Adv.nced Ceramics 2017年第1期6卷 92-页

作者： Elena F.KRIv.SHAPKINA Pav.l v.KRIv.SHAPKIN aleksey A.v.DYAGIN Institute of Chemistry of Komi SC UB RAS Syktyvkar 167982 Russia ITMO University St.Petersburg 197101 Russia Boreskov.Institute of Catalysis SB RAS Novosibirsk 630090 Russia National Research Tomsk Polytechnic University Tomsk 634050 Russia

A series of asymmetric cordierite ceramics with hierarchical porous structure were prepared and *** macroporous support was obtained from natural raw materials (bauxite,silica sand,kaolinite,talc,and alumina) v.a ceramic *** prepared ceramic discs were characterized by a narrow pore size *** av.rage pore size was about 9.5 μm,and the open porosity was estimated to be 30％.Coating the discs with micro/mesoporous cordierite layer was performed using the sol-gel ***-component sols were obtained from organic or inorganic *** gels were calcined at 1200 ℃ to form the cordierite *** nature of precursor was found to affect the pore v.lume *** pore v.lume distribution was observ.d when organic precursors were *** key factor to control the parameters of final material was the drying *** drying of the gels has allowed us to increase the surface area in two orders of magnitude comparing with conv.ntional drying procedure.

关键词： sol-gel method aerogels cordierite Al2O3-SiO2-MgO hierarchical porous structure

Enigmatic Glass-Like Carbon from the Alpine Foreland, Southeast Germany: A Natural Carbonization Process

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Acta Geologica Sinica(English Edition) 2018年第6期92卷 2179-2200页

作者： Tatyana G. SHUMILOv. Sergey I. ISAENKO v.sily v. ULYASHEv.Boris A. MAKEEv.Michael A. RAPPENGLüCK aleksey A. v.LIGZHANIN Kord ERNSTSON Institute of Geology of Komi Scientific Center of Ural Branch of Russian Academy of Sciences Pervomayskaya st.54Syktyvkar167982Russia Hawaii Institute of Geophysics and Planetology University of Hawaii at Manoa1680 East-West RoadHonoluluHI96822USA Institute for Interdisciplinary Studies GilchingGermany National Research Center 《Kurchatov.Institute》 Akademika Kurchatova pl.1Moscow123182Russia Faculty of Philosophy I University of WürzburgGermany

Unusual carbonaceous matter, termed here chiemite, composed of more than 90% C from the Alpine Foreland at Lake Chiemsee in Bav.ria, southeastern Germany has been inv.stigated using optical and atomic force microscopy, X-ray fluorescence spectroscopy, scanning and transmission electron microscopy, high-resolution Raman spectroscopy, X-ray diffraction and differential thermal analysis, as well as by δ13 C and 14 C radiocarbon isotopic data analysis. In the pumice-like fragments, poorly ordered carbon matter co-exists with high-ordering monocrystalline α-carbyne, and contains submicrometersized inclusions of complex composition. Diamond and carbyne add to the peculiar mix of matter. The required v.ry high temperatures and pressures for carbyne formation point to a shock ev.nt probably from the recently proposed Holocene Chiemgau meteorite impact. The carbon material is suggested to hav. largely formed from heav.ly shocked coal, v.getation like wood, and peat from the impact target area. The carbonization/coalification high PT process may be attributed to a strong shock that instantaneously caused the complete ev.poration and loss of v.latile matter and water, which nev.rtheless preserv.d the original cellular structure seen fossilized in many fragments. Relativ.ly fresh wood encapsulated in the purported strongly shocked matter point to quenched carbon melt components possibly important for the discussion of surv.v.l of organic matter in meteorite impacts, implying an astrobiological relationship.

关键词： astrobiology diamond carbyne coalification carbonization meteorite impact chiemite

Impact of Geomagnetically Induced Currents Secondary Ev.nt on the High-v.ltage Synchronous Motors

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Engineering（科研） 2013年第10期5卷 21-26页

作者： v.ra v. v.khnina aleksey A. Kuv.hinov Institute of Power Engineering and Electrical Engineering Togliatti State University Togliatti Russia

It is justified that during geomagnetic storms the high v.ltage synchronous engines are being impacted by high current harmonics of ev.n sequences powered by power transformer due to geo-induced high v.ltage currents flowed through the windings. Equiv.lent circuits of step down substation and Hv.synchronous motors are made for making it possible to consider a saturation of power transformer magnetic system and higher current harmonics av.ilability in stator windings. Analytic expressions for higher current harmonics and extra capacity losses calculation in stator windings are receiv.d, as well as the calculation of induction torques allowing to denote a rate of geomagnetic processes impact on synchronous engine operation at v.rious step down substation parameters.

关键词： Geomagnetically Induced Current Step Down Substation Power Transformer Synchronous Motor High Order Harmonics

Neochaetosphaerella thaxteriospora *** *** Tympanopsis texensis ***.(Coronophorales,Ascomycota)from Texas,USA

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Fungal Div.rsity 2012年第1期52卷 191-196页

作者： Larissa N.v.silyev. aleksey v.Chernyshev.Stev.n L.Stephenson Institute of Biology and Soil Sciences Far East Branch of the Russian Academy of SciencesVladivostokRussia A.v.Zhirmunsky Institute of Marine Biology Far East Branch of the Russian Academy of SciencesVladivostokRussia Department of Biological Sciences University of ArkansasFayettevilleAR 72701USA

Ascomata of three species of coronophoraceous fungi collected from the Big Thicket National Preserv. and an area immediately adjacent to the preserv. were examined with a scanning electron microscope to rev.al the distinctiv. features of the ascomatal *** on the results of the examination,two new species(Neochaetosphaerella thaxteriospora and Tympanopsis texensis)are herein described and *** a description and an illustration of Scortechinia acanthostroma are also prov.ded.

关键词： Coronophoraceous fungi Neochaetosphaerella Scortechinia Tympanosis

Electro–optic response in thin smectic C* film with chev.on structures

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Chinese Physics B 2016年第12期25卷 337-343页

作者： aleksey A Kudreyko Nail G Migranov.Dana N Migranov. Ufa State Petroleum Technological Univ.rsity Department of Physics Bashkir State Pedagogical Univ.rsity Department of General and Theoretical Physics

The effects in electrostatic models of chev.on surface-stabilized ferroelectric liquid crystals are inv.stigated through numerical modeling. To study smectic C＊ director distribution within the cell, we consider two nonlinear approaches： the chev.on interface does not interplay with the electric field; the electric field interplays with the chev.on interface. The obtained results of the director field distribution are compared with the earlier linearized studies. We find that whether or not the electric field interplays with the chev.on interface, the electro-optic response requires a generalized approach for its description. The threshold electric field, which is necessary for switching between two stable director states in the chev.on cell is ev.luated. This study suggests that, in many cases of practical interest, electro-optic response to the electric field and the threshold electric field can be precisely estimated. We argue that, beside being numerically efficient, our approach prov.des a conv.nient and a nov.l standpoint for looking at the electro-optic response problem.

关键词： surface-stabilized ferroelectric liquid crystal chev.on structure thin films bistability Euler'sequation

Considering temperature dependence of thermo-physical properties of sandy soils in two scenarios of oil pollution

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Research in Cold and Arid Regions 2014年第4期6卷 302-308页

作者： aleksey v.Malyshev.Anatoly M.Timofeev Institute of Physical-Technical Problems of the North. v.P. Larionov Siberian Branch of the Russian Academy of Sciences

We analyzed the heat conductiv.ty and v.lumetric heat capacity of sandy soil contaminated in two scenarios of oil pollution, and also determined the temperature dependencies of these changed thermophysical properties. In the first pollution scenario, the oil product was introduced into wet riv.r sand, and in the second case, dry sand was contaminated by the oil product and was then moistened with water. By considering these two scenarios as multicomponent dispersion systems with v.rying degrees of contamination and humidity, and by using a polystructural granular model with pore spaces and closed inclusions, we calculated that the heat conductiv.ty of the sandy soil increased under the first pollution scenario and decreased under the second, but the change in the v.lumetric heat capacity of the sandy soil was proportional only to the amount of oil pollution, not the manner in which it was introduced. We also determined the temperature dependencies of these two thermophysical properties of sandy soil when polluted by oil, of which information will be useful for future containment and remediation of oil-contaminated soil.

关键词： sandy soil heat conductiv.ty heat capacity heat resistance pollution oil product unfrozen water v.lumeconcentration coordination number