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Influence of frost weathering on the recession of surfaces of technogenic landforms in Yakutia

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作者： Ashanie Gunathillake andrey V.Savkin School of Electrical Engineering and Telecommunication University of New South Wales Data61|CSIRO EveleighNSW 2015

ISBN: (纸本)9781538629185

Source seeking in emergency environment is a vital issue,which has attracted the attention of researchers *** this paper,we consider a robot traveling with a constant speed and guided by sensor *** control law does not depend on any gradient dependent *** robot is navigated using an angular velocity limited by a maximum and minimum *** robot location is calculated using the sensor neighborhood topology coordinates,which is an alternative to the physical coordinate *** topology coordinate system,actual physical distances are ***,the proposed control law does not incorporate any distance ***,the performance of the proposed method is evaluated using computer simulation and presented in this paper.

关键词： Gradient Climbing Navigation Source Seeking Topology Maps

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Research in Cold and Arid Regions 2019年第4期11卷 257-266页

作者： andrey E.Melnikov Nikolay N.Grib Melnikov Permafrost Institute of the Siberian Branch of the Russian Academy of Sciences Yakutsk 677010Russia Technical Institute(branch)of M.K.Ammosov North-eastern Federal University Neryungri 678960Russia

The article assesses the influence of permafrost weathering on the rate of destruction of technogenic land forms,as exhibit ed on as illustrated by the railway embankment of the Amur Yakut mainline in the Sakha Republic(Yakutia).Studies were carried out on a railway section more than 375 km *** subsidence rate of the embankment slopes and structur al excavations was determined using laboratory methods that simulate various mechanisms of temperature(with a transi tion through 0℃)impact on *** the first time,a quantitative assessment of the influence of cryogenic weathering on the stability of the railway in the region belonging to the northern building climatic zone is *** the territory un der consideration,embankment rocks were experimentally determined to undergo more than 100 freezing and thawing cy cles during a *** the existing climatic conditions,cryogenic weathering actively affects the embankment of the railway to a depth of 30 *** of the embankment deformations detected during field observations are due to defects in the integrity of this particular *** size of the disintegrating layer of particular types of rock comprising the rail way embankment has been established as reaching 10 cm per *** 5 years following the formation of embankments comprising the upper structure of the railroad tracks,the physical and mechanical properties of rocks,which initially had a tensile strength for uniaxial compression in the range of 40 70 MPa,were reduced by more than 50%.According to the authors,the establishment of regional cryohypergenesis features is universal in nature and can be applied to solving a wide range of tasks related to the assessment and prediction of the degree of cryogenic transformation of rocks having different structural properties.

关键词： cryogenic weathering embankment railway subsidence rate Republic of Sakha Yakutia

Methodology-driven efficient synthesis of cytotoxic(±)-piperarborenine B

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Green Synthesis and Catalysis 2022年第4期3卷 339-348页

作者： Chunngai Hui andrey P.Antonchick Max Planck Institute of Molecular Physiology Department of Chemical BiologyDortmund 44227Germany Technical University Dortmund Faculty of Chemistry and Chemical BiologyDortmund 44221Germany Nottingham Trent University School of Science and TechnologyDepartment of Chemistry and ForensicsNottingham NG118NSUnited Kingdom

The evolution of synthetic design toward the efficient synthesis of cyclobutane natural product(±)-piperarborenine B is *** the advantages of good functional group compatibility of contractive synthesis of cyclobutanes from pyrrolidines,stereoselective synthesis of unsymmetric highly functionalized cyclobutanes core of(±)-piperarborenine B was realized in one ***,an unprecedented carboxylic acid assisted-diastereoselective Kracho decarboxylation/transmethylation features a new strategy for a non-symmetrical cyclobutane *** synthesis of(±)-piperarborenine B illustrates the advancement of methodology resulting in the improvement in synthetic efficiency.

关键词： Cyclobutane Molecular editing Ring contraction Stereoselective synthesis Protecting group free

Spark Plasma Sintering of Boron Carbide Using Ti_(3)SiC_(2) as a Sintering Additive

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Journal of Wuhan University of Technology(Materials Science) 2024年第3期39卷 645-650页

作者： Hülya Biçer Mustafa Tuncer Hasan Göçmez Iurii Bogomol Valerii Kolesnichenko andrey Ragulya Kutahya Dumlupinar University School of EngineeringDepartment of Metallurgical and Materials EngineeringKütahya 43100Tur-key Boron Based Advanced Ceramics Application and Research Center Kütahya Dumlupınar UniversityKütahya 43100Turkey Advanced Technologies Center(İLTEM) Kütahya Dumlupınar UniversityKütahya 43000Turkey Department of High-Temperature Ma-terials and Powder Metallurgy National Technical University of Ukraine“Igor Sikorsky Kyiv Polytechnic Institute”Kyiv 03056Ukraine Frantsevich Institute for Problems of Materials Science National Academy of Sciences of UkraineKyiv 03056Ukraine

Boron carbide has unique properties for wide application possibilities;however,poor sinterability limits its *** approach to overcome this limitation is the addition of secondary phases into boron *** carbide based composite ceramics are produced by the direct addition of secondary phases into the structure or via reactive sintering using a sintering *** present study investigated the effect of Ti_(3)SiC_(2) addition to boron carbide by reactive spark plasma sintering in the range of 1700-1900℃.Ti_(3)SiC_(2) phase decomposed at high temperatures and reacted with B4C to form secondary phases of TiB2 and *** results demonstrated that the increase of Ti_(3)SiC_(2) addition(up to 15 vol%)effectively promoted the densification of B4C and yielded higher ***,as the amount of Ti_(3)SiC_(2) increased further,the formation of microstructural inhomogeneity and agglomeration of secondary phases caused a decrease in hardness.

关键词： reactive sintering SPS boron carbide MAX phase

Efficient passivation of DY center in CH_(3)NH_(3)PbBr_(3) by chlorine:Quantum molecular dynamics

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Nano Research 2022年第3期15卷 2112-2122页

作者： Ran Shi Wei-Hai Fang andrey S.Vasenko Run Long Oleg V.Prezhdo College of Chemistry Key Laboratory of Theoretical&Computational Photochemistry of Ministry of EducationBeijing Normal UniversityBeijing 100875China National Research University Higher School of Economics(HSE)University 101000 MoscowRussia Donostia International Physics Center(DIPC) Paseo Manuel de Lardizabal 4San Sebastián/Donostia20018 Basque CountrySpain Department of Chemistry University of Southern CaliforniaLos AngelesCA 90089USA

MAPbBr_(3)(MA=CH_(3)NH_(3)^(+))doping with bismuth increases electric conductivity,charge carrier density and photostability,reduces toxicity,and expands light ***,Bi doping shortens excited-state lifetimes due to formation of DY−charge recombination *** nonadiabatic molecular dynamics and time-domain density functional theory,we demonstrate that the DY−center forms a deep,highly localized hole trap,which accelerates nonradiative relaxation ten-fold and is responsible for 90%of carrier *** trapping occurs by coupling between the valence band and the trap state,facilitated by the Br atoms surrounding the Bi *** of the DY−center with chlorines heals the local geometry distortion,eliminates the trap state,and makes the carrier lifetimes longer than even in pristine MAPbBr_(3).The decreased charge recombination arises from reduced nonadiabatic coupling and shortened coherence time,due to diminished electron–hole overlap around the passivated *** study demonstrates accelerated nonradiative recombination in Bi-doped MAPbBr_(3),suggests a strategy for defect passivation and reduction of nonradiative energy losses,and provides atomistic insights into unusual defect properties of metal halide perovskites needed for rational design of high-performance perovskite solar cells and optoelectronic devices.

关键词： Hybrid organic-inorganic perovskite DY−center and Cl passivation charge trapping and recombination nonadiabatic molecular dynamics time-domain density functional theory.

Nucleation of methane hydrate and ice in emulsions of water in crude oils and decane under non-isothermal conditions

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Chinese Journal of Chemical Engineering 2019年第3期27卷 668-676页

作者： andrey S. Stoporev Lidiya I. Svarovskaya Larisa A. Strelets Lubov’ K. Altunina Galina V. Villevald Tamara D. Karpova Tatyana V. Rodionova andrey Yu. Manakov Nikolaev Institute of Inorganic Chemistry SB RAS Novosibirsk State University Institute of Petroleum Chemistry

Achievable supercooling for the formation of methane hydrate from water emulsions was studied in seven different crude oils and in decane. The experiments were performed under constant rate cooling from + 20 to-15 °C and a pressure of methane of 12 MPa. It was demonstrated that the shapes and positions of the resulting survival curves depend on the density, viscosity and dispersive power of oil samples used in the experiments, as well as on the degree of oil oxidation. In addition, results of the experiments on ice freezing under the same emulsions are presented. The results obtained in the work allowed us to discuss the possibility and features of primary and secondary nucleation of the hydrate and ice in the systems under consideration.

关键词： Methane hydrate Crude oil Oil dispersive system Nucleation

Carbon–Iron Microfibrous Material Produced by Thermal Treatment of Self-rolled Poly(4-vinyl pyridine) Films Loaded by Fe_2O_3 Particles

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Journal of Materials Science & Technology 2015年第9期31卷 881-887页

作者： Camelia Matei Ghimbeu Aleksandr I.Egunov andrey S.Ryzhikov Valeriy A.Luchnikov Institut de Science des Matériaux de Mulhouse

Ensembles of freeze-dried self-rolled polymer micro-scrolls are explored as template media for produc- ing carbon-iron based composites with fibrous morphology. Polymer fibres impregnated with furfuryl alcohol and loaded with Fe2O3 particles, were thermally treated under inert atmosphere at 700 ℃ and subsequently analysed by scanning and transmission electron microscopy, X-ray diffraction, thermogravimetric analysis, and nitrogen adsorption. The resulting material has a micro-fibrous mor- phology and is basically composed of metallic Fe^0 and FeO particles, i.e., more than 98 wt% of the carbon/ iron-based composite mass. These particles are held together by amorphous porous carbon foam obtained by in-situ carbonization of the polymer/Fe2O3 composite with evacuation of carbon from the system via COx gases released by carbo-reduction of Fe2O3. The material has significant activity in the reaction of catalytic decomposition of hydrogen peroxide in water solutions.

关键词： Composite materialsPorous carbonPolymersIron particles

Information-based reduced reference image quality assessment incorporating non-tensor product wavelet filter banks

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Chinese Science Bulletin 2014年第16期59卷 1917-1924页

作者： Yong Ding Yuan Zhang Xiaolang Yan andrey S.Krylov Institute of VLSI Design Zhejiang University Laboratory of Mathematical Methods of Image Processing Lomonosov Moscow State UniversityMoscowRussia

To achieve the better performance of image quality assessment,this paper develops an informationbased ***,visual maps that contain visual information are extracted by non-tensor product wavelet filter banks at different ***,to model visual difference(VD)caused by image degradations,the variation of information entropy between distorted and reference images is *** the final visual quality is calculated with the VDs at each *** experiments,evaluation results show that it performs very well in terms of high accuracy of image quality measurement as well as low data rate.

关键词：图像质量评价非张量积小波视觉信息滤波器组基础数据传输速率退化模型视觉质量

Evolution of metabolic scaling among the tetrapod:effect of phylogeny,the geologic time of class formation,and uniformity of species within a class

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Integrative Zoology 2022年第5期17卷 904-917页

作者： Valery M.GAVRILOV Tatiana B.GOLUBEVA andrey V.BUSHUEV Department of Vertebrate Zoology M.V.Lomonosov Moscow State UniversityMoscowRussia Zvenigorod Biological Station M.V.Lomonosov Moscow State UniversityMoscowRussia

The metabolic scaling in the animal has been discussed for over 90 years,but no consensus has been *** analysis of 2126 species of vertebrates reveals a signiﬁcant allometric exponent *** show that classes of terrestrial vertebrates exhibit the evolution of metabolic *** the allometric coefﬁcient“a”and the allometric exponent“b”change naturally,but differently depending on the geological time of group *** allometric coefﬁcient“a”shows the measure of the evolutionary development of systems that forms resting metabolism in *** classes,such as birds and mammals,have a metabolic rate that is in an order of magnitude higher than that in ectothermic classes,including amphibians and *** the terrestrial vertebrate phylogeny,weﬁnd that the metabolic scaling is characterized by 3 main allometric exponent values:b=3/4(mammals),b>3/4(ectotherms,such as amphibians and reptiles),and b<3/4(birds).The hetero-geneity of the allometric exponent is a natural phenomenon associated with the general evolution of *** scaling factor decreases depending on both the external design and the size(birds vs mammals)of the *** metabolic rate and uniformity of species within a class increase as the geological start date of for-mation of the class approaches the present *** higher the mass-speciﬁc standard metabolic rate in the class,the slower metabolic rate grows with increasing body size in this *** results lay the groundwork for further exploration of the evolutionary and ecological aspects of the development of metabolic scaling in animals.

关键词： geological time metabolic rate scaling