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Belowground Tritrophic Food Chain Modulates soil Respiration in Grasslands

Pedosphere 2018年第1期28卷 114-123页

作者： andrey s.ZAITsEV Klaus BIRKHOFER Klemens EKsCHMITT Volkmar WOLTERs Institute of Animal Ecology Justus-Liebig-University of Giessen Department of Ecology Brandenburg University of Technology Cottbus-Senftenberg

Edaphic biota significantly affects several essential ecological functions such as C-storage, nutrient turnover, and ***, it is not completely understood how belowground animal contribution to these functions changes in grasslands subject to different land use types. A microcosm experiment was carried out to test the effect of a tritrophic food chain on CO_2 release from grassland soils. soil was collected from three differently managed grassland systems(meadow, pasture, and mown pasture) located in three distinct German regions that cover a north-south gradient of approximately 500 km. The tritrophic food chain comprised natural edaphic microflora, nematodes, and predatory gamasid mites. The experimental design involved a full factorial combination of the presence and absence of nematodes and gamasid mites. Nematodes significantly increased the CO_2 emissions in most treatments,but the extent of this effect varied with land use type. The fact that grazing by nematodes stimulated the metabolic activity of the edaphic microflora over a wide range of grassland soils highlighted the critical impact of the microfauna on ecosystem services associated with soil organic matter dynamics. Gamasids slightly amplified the effect of nematodes on microbial metabolic activity,but only in the pastures. This effect was most probably due to the control of nematode abundance. The fact that gamasid addition also augmented the impact of environmental conditions on nematode-induced modulation of soil respiration highlighted the need for including land use differences while evaluating soil fauna contribution to soil processes. To conclude, the differential response of the investigated tritrophic food chain to different grassland management systems suggests that adverse effects of land use intensification on important soil processes such as atmospheric C-release could potentially be reduced by using management methods that preserve essential features of the belowground fo

关键词： CO_2 emission land use microcosm nematodes predatory mites soil fauna soil food webs

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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

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Early Jurassic Climate Warming in Eastern siberia: First Macrofloristic Evidence from Irkutsk Basin, Russia

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Acta Geologica sinica(English Edition) 2024年第4期98卷 1035-1050页

作者： andrey FROLOV Irina MAsHCHUK Institute of the Earth's Crust Siberian Branch of the Russian Academy of SciencesIrkutsk664033Russia

Numerous new records of Ferganiella, Podozamites, and schidolepium, including a new species, Ferganiella ivantsovii sp. nov., are described from the Early Jurassic(Toarcian) Middle subformation of the Prisayan Formation from the Euro-sinian paleofloristic region in the Irkutsk Basin, Eastern siberia, Russia. An analysis of the paleogeographic distribution of Ferganiella and Podozamites shows that both genera were the most diverse and numerous in the East Asian province of the Euro-sinian region and in the Northern Chinese province of the siberian region during the Early and Middle Jurassic. These phytochoria were located in the subtropical and temperate subtropical climate zones, which allows us to consider Ferganiella and Podozamites as thermophilic plants, which are important indicators of the Early Toarcian climatic optimum. Their abundance in the Irkutsk Basin thus may indicate Early Toarcian warming;further abundant schidolepium cones, which produced Araucariacites pollen, typical for Euro-sinian flora complement the scenario. Thus, the new finds are the first macrofloristic indicators of the Toarcian climatic optimum in the Irkutsk Basin.

关键词： paleobotany Ferganiella Podozamites schidolepium Toarcian climatic optimum paleobiogeography siberian paleofloristic region Irkutsk

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Monocotyledon-like Leaves from the Middle Jurassic of East siberia(Russia)

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Acta Geologica sinica(English Edition) 2022年第6期96卷 1884-1896页

作者： andrey FROLOV Ilya ENUsHCHENKO Institute of the Earth’s Crust Siberian Branch of the Russian Academy of SciencesIrkutsk 664033Russia Limnological Institute Siberian Branch of the Russian Academy of SciencesIrkutsk 664033Russia

Leaf fragments of Herbifolia antiqua *** et Enushchenko *** *** the Middle Jurassic(Aalenian)of the Irkutsk Coal Basin(Eastern siberia,Russia)are *** following features are characteristic of *** *** ***.:the presence of leaf sheaths,linear smooth-edged leaves with parallel venation,anastomoses between the veins,anomocytic stomata,rhomb-shaped ordinary epidermal *** a combination of characters is widespread in modern monocotyledonous plants and is absent in fossil and modern cryptogam and *** to the lack of evidence of an enclosed ovule in *** *** ***.,we attribute it to a typological angiosperm,based on its unique leaf structure characteristic of *** leaf epidermal structure of Herbifolia *** most similar to those of modern Asparagales and Liliales.

关键词： monocotyledons leaf epidermis new taxa Jurassic angiosperm Irkutsk Coal Basin

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Two New species of Eretmophyllum(Ginkgoales)from the Jurassic of Eastern siberia

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Acta Geologica sinica(English Edition) 2023年第4期97卷 1014-1025页

作者： andrey FROLOV Irina MAsHCHUK Institute of the Earth's Crust Siberian Branch of the Russian Academy of SciencesIrkutsk 664033Russia

Two new species of Eretmophyllum Thomas are described from the lower(Toarcian)and upper(Aalenian)Prisayan Formation of the Irkutsk Basin,Eastern siberia,Russia based on distinct morphological and cuticular features of the leaves that distinguish them from other species of the *** polypapillosum *** characterized by the presence of 2-3 papillae on the lower and upper epidermis of ordinary ***,the leaf burials of *** *** that it preferred mesophilic forests developed on river terraces and/or low *** yershowskiensis *** represented exclusively by leaf cuticles extracted by coal maceration,and it probably inhabited the low banks of peat *** presence of the genus Eretmophyllum in the Early Jurassic of France and Eastern siberia shows that it was already widespread in the territory of Eurasia,distributed from Western Europe to Eastern *** indicates the possible existence of Eretmophyllum species elsewhere in the Early Jurassic such as Central Asia and Northwest China.

关键词： paleobotany ginkgoalean taxonomy paleophytogeography paleoecology leaf cuticles Irkutsk Coal Basin

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Photon-pair generation in a quadratically nonlinear parity-time symmetric coupler

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Photonics Research 2018年第4期6卷 I0006-I0009页

作者： DIANA A.ANTONOsYAN ALEXANDER s.sOLNTsEV andrey A.sUKHORUKOV Nonlinear Physics Centre Research School of Physics and Engineering Australian National University school of Mathematical and Physical sciences University of Technology Sydney

Integrated nonlinear waveguide structures enable generation of quantum entangled photons. We describe theoretically the effects of spatially inhomogeneous loss on the creation of photon pairs through spontaneous parametric down-conversion in quadratically nonlinear directional couplers, where photons experience effective parity-time(PT) symmetric potential due to the presence of optical loss in one of the waveguides. We show that for losses below the PT-breaking threshold, the quantum photon states can be flexibly tuned similarly to conservative couplers, whereas for stronger losses, the correlations between two waveguide modes are suppressed. We also formulate a quantum-classical correspondence with sum-frequency generation for fast evaluation of device *** results can be applied for the design of quantum plasmonic circuits.

关键词：非线性波导结构量子光子通讯技术

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Impacts of late Quaternary environmental change on the long-tailed ground squirrel(Urocitellus undulatus)in Mongolia

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Zoological Research 2018年第5期39卷 364-372页

作者： Bryan s.McLean Batsaikhan Nyamsuren andrey Tchabovsky Joseph A.Cook University of Florida Florida Museum of Natural History Department of Biology School of Arts and Sciences National University of Mongolia Laboratory of Population Ecology A.N. Severtsov Institute of Ecology and Evolution University of New Mexico Department of Biology and Museum of Southwestern Biology

Impacts of Quaternary environmental changes on mammal faunas of central Asia remain poorly understood due to a lack of comprehensive phylogeographic sampling for most *** help address this knowledge gap,we conducted the most extensive molecular analysis to date of the long-tailed ground squirrel （Urocitellus undulatus Pallas 1778） in Mongolia,a country that comprises the southern core of this species＇ *** on material from recent collaborative field expeditions,we genotyped 128 individuals at two mitochondrial genes （cytochrome b and cytochrome oxidase Ⅰ;1797 bp total）.Phylogenetic inference supports the existence of two deeply divergent infraspecific lineages （corresponding to subspecies *** and ***）,a result in agreement with previous molecular investigations but discordant with patterns of range-wide craniometric and external phenotypic *** the widespread western eversmanni lineage,we recovered geographically-associated clades from the：（a） Khangai,（b） Mongolian Altai,and （c） Govi Altai mountain *** structure in *** is consistent with an isolation-by-distance model;however,genetic distances are significantly lower than among subspecies,and intra-clade relationships are largely *** latter patterns,as well as the relatively higher nucleotide polymorphism of populations from the Great Lakes Depression of northwestern Mongolia,suggest a history of range shifts into these lowland areas in response to Pleistocene glaciation and environmental change,followed by upslope movements and mitochondrial lineage sorting with Holocene *** study illuminates possible historical mechanisms responsible for *** genetic structure and contributes to a framework for ongoing exploration of mammalian response to past and present climate change in central Asia.

关键词： Central Asia Gobi Desert Great LakesDepression Mongolia Phylogeography

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Example-based dynamic façade design using the façade daylighting performance improvement(FDPI)indicator

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Building simulation 2023年第12期16卷 2261-2283页

作者： Luka Akimov andrey Bezborodov Vladimir Badenko Peter the Great saint-Petersburg Polytechnic University 29 Polytechnicheskaya st.St.Petersburg195251Russian Federation Politecnico di Milano 32 Piazza Leonardo da VinciMilano20133Italy

It remains challenging to conduct an efficient dynamic façade *** this article authors try to address this issue introducing the façade daylighting performance improvement(FDPI)indicator aimed to evaluate the performance of a dynamic(adaptive)façade from its daylighting performance point of *** illustrate the FDPI application the authors introduced the preliminary dynamic façade concept for an office building located in Tel Aviv(Hot-summer Mediterranean Climate Csa)with further shape modification based on the daylighting performance analysis compared to the three alternatives representative of different typologies of dynamic faç*** Bahr,One Ocean and The University of southern Denmark façade systems were simulated under the same weather and building conditions of the preliminary dynamic façade concept and were considered as a benchmark for the *** final dynamic façade concept elaborated by the authors in the preliminary comparative workflow showed noticeable daylight performance improvement with respect to the case studies comparative *** FDPI metric allowed to estimate a daylighting performance improvement of 43%of the final dynamic façade concept over the case study dynamic façade that showed the best performance in the daylighting simulations.

关键词： dynamic façade adaptive façade daylight performance performance evaluation façade daylighting performance Improvement

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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.

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On the nonlocal stabilization by starting control of the normal equation generated from the Helmholtz system

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science China Mathematics 2018年第11期61卷 2017-2032页

作者： andrey Fursikov Lyubov Osipova Department of Mechanics & Mathematics Moscow State University Mathematical Fluid Dynamics Laboratory Voronezh State University

We consider the problem of stabilization near zero of semilinear normal parabolic equations connected with the 3D Helmholtz system with periodic boundary conditions and arbitrary initial *** problem was previously studied in Fursikov and shatina(2018).As it was recently revealed,the control function suggested in that work contains a term impeding transferring the stabilization construction on the 3D Helmholtz *** main concern of this paper is to prove that this term is not necessary for the stabilization result,and therefore the control function can be changed by a proper way.

关键词： equations of normal type nonlocal stabilization starting control estimates of stabilized solutions

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