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Immediate and legacy effects of snow exclusion on soil fungal diversity and community composition

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Forest Ecosystems 2021年第2期8卷 292-302页

作者： Li zhang Yuzhi Ren Kaijun Yang Zhijie Li Bo Tan Yang Liu Han Li Chengming You Sining Liu Lixia Wang Rui Yin Jian zhang Zhenfeng Xu Forestry Ecological Engineering in the Upper Reaches of the Yangtze River Key Laboratory of Sichuan Province&National Forestry and Grassland Administration Key Laboratory of Forest Resources Conservation and Ecological Safety on the Upper Reaches of the Yangtze River&Rainy Area of West China Plantation Ecosystem Permanent Scientific Research Base Institute of Ecology&ForestrySichuan Agricultural UniversityChengdu 611130China Global Ecology Unit CREAF-CSIC-UAB CSIC08193 BarcelonaCataloniaSpain Forschungszentrum Jülich GmbH Agrosphere(IBG-3)JülichGermany Helmholtz-Centre for Environmental Research-UFZ Department of Community EcologyTheodor-Lieser-Strasse 406110 Halle(Saale)Germany

Background:Soil fungi play crucial roles in ecosystem ***,how snow cover change associated with winter warming affects soil fungal communities remains unclear in the Tibetan ***:We conducted a snow manipulation experiment to explore immediate and legacy effects of snow exclusion on soil fungal community diversity and composition in a spruce forest on the eastern Tibetan *** fungal communities were performed by the high throughput sequencing of ***:Ascomycota and Basidiomycota were the two dominant fungal phyla and Archaeorhizomyces,Aspergillus and Amanita were the three most common genera across seasons and snow *** exclusion did not affect the diversity and structure of soil fungal community in both snow-covered and snow-free ***,the relative abundance of some fungal communities was different among *** fungal groups were correlated with environmental factors(i.e.,temperature and moisture)and soil biochemical variables(i.e.,ammonium and enzyme).Conclusions:These results suggest that the season-driven variations had stronger impacts on soil fungal community than short-term snow cover *** findings may have important implications for soil microbial processes in Tibetan forests experiencing significant decreases in snowfall.

关键词： Winter climate change Snow cover Fungi Community diversity Community composition Illumina sequencing

Atomic-scale investigation of spinel Li Fe5O8 thin films on SrTiO3(001) substrates

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Journal of Materials Science & Technology 2020年第5期40卷 31-38页

作者： Kun Liu Ruyi zhang Lu Lu Shaobo Mi Ming Liu Hong Wang Shengqiang Wu Chunlin Jia State Key Laboratory for Mechanical Behavior of Materials&School of Microelectronics Xi’an Jiaotong UniversityXi’an 710049China Department of Materials Science and Engineering Southern University of Science and TechnologyShenzhen 518055China Ernst Ruska Center for Microscopy and Spectroscopy with Electrons Forschungszentrum Jülich52425 JülichGermany

Microstructural properties of spinel Li Fe5O8(LFO)films grown on(001)-oriented Sr TiO3(STO)substrates have been investigated at the atomic-scale by advanced electron microscopy *** types of orientation relationship(OR)between the LFO films and the STO substrates have been determined,cube-on-cube and(111)[ī10]LFO//(111)[1ī0]*** boundaries(APBs)and three types of twin boundaries(TBs)form within the LFO films,and the propagation of TBs and APBs results in their complex *** most cases,interactions between TBs and APBs change the type of TBs and terminate the propagation of APBs since the APBs introduce a displacement vector of(a/4)110 into the *** addition,the interactions between two coherent TBs are observed to generate the incoherent *** epitaxial strain of the LFO/STO(001)heterosystem can be released by the formation of TBs and APBs in the films and misfit dislocations at the *** that the magnetic coupling across the APBs and TBs can lead to novel physical properties,the appearance of APBs and TBs with a high density in the LFO films would affect the magnetic properties of the films.

关键词： Lithium ferrite Twin boundaries Antiphase boundaries Interactions Electron microscopy

A review of gas-phase chemical mechanisms commonly used in atmospheric chemistry modelling

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Journal of Environmental Sciences 2023年第1期123卷 522-534页

作者： Yanhui Liu Jiayin Li Yufang Ma Ming Zhou Zhaofeng Tan Limin Zeng Keding Lu Yuanhang zhang State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Science and EngineeringPeking UniversityBeijing 100871China Institute of Energy and Climate Research IEK-8:TroposphereForschungszentrum Jülich GmbHJülich 52428Germany

The atmospheric chemical mechanism is an essential component of airshed models used for investigating the chemical behaviors and impacts of *** the first tropospheric chemical mechanism was proposed in the 1960s,various mechanisms including Master Chemical Mechanism(MCM),Carbon Bond Mechanism(CBM),Statewide Air Pollution Research Center(SAPRC)and Regional Atmospheric Chemistry Mechanism(RACM)have been developed for different research *** work summarizes the development and applications of these mechanisms,introduces their compositions and lumping methods,and compares the ways the mechanisms treat radicals with box model *** can reproduce urban pollution events with relatively low cost compared to SAPRC and RACM,whereas the chemical behaviors of radicals and the photochemical production of ozone are described in detail in *** photolysis rates of some oxygenated compounds are low in SAPRC07,which may result in underestimation of radical *** an explicit chemical mechanism,MCM describes the chemical processes of primary pollutants and their oxidation products in *** can be used to investigate certain chemical processes;however,due to its large size,it is rarely used in regional model simulations.A box model case study showed that the chemical behavior of OH and HO_(2)radicals and the production of ozone were well described by all *** and SAPRC underestimated the radical levels for different chemical treatments,leading to low ozone production values in both *** and RACM are widely used in box model studies,while CBM and SAPRC are often selected in regional simulations.

关键词： Atmospheric chemistry Gas-phase chemical mechanism Ozone Box model

Substituent Effects of Pyridyl-methylene Cyclopentadienyl Rare-earth Metal Complexes on Styrene Polymerization

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Chinese Journal of Polymer Science 2019年第6期37卷 570-577页

作者： Zhen zhang Zhong-Yi Cai Yu-Peng Pan Yan-Li Dou Shi-Hui Li Dong-Mei Cui Key Laboratory of Automobile Materials of Ministry of Education Department of Materials Science and Engineering Jilin University State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences

Salt metathesis reactions between pyridyl-methylene-cyclopentadienyl lithium salt and LnCl_3 followed by the addition of two equivalents of lich_2SiMe_3 afforded a series of constrained-geometry-configuration rare-earth metal bis(alkyl) complexes(Cp′CH_2-Py)Ln(CH_2SiMe_3)_2(THF)_n(Py = C_5H_4N, Cp′ = C_5H_4(Cp), Ln = Sc, n = 0(1); Cp′ = C_9H_6(Ind), Ln = Sc, n = 0(2); Cp′ = 3-Me_3Si-C_9H_5(3-Me_3Si-Ind), Ln = Sc, n = 0(3a), Ln = Lu(3b), Y(3c), n = 1; Cp′ = 2,7-(~tBu)_2C_(13)H_8(2,7-(~tBu)_2-Flu), Ln = Sc(4 a), n = 0, Ln = Lu(4b),Y(4c), n = 1) in moderate to good yields, which were characterized by NMR spectroscopy and single-crystal X-ray diffraction(for complex 3a). In the presence of [Ph_3C][B(C_6F_5)_4] and Al^iBu_3, these complexes displayed different performances towards styrene polymerization. Rare-earth metal bis(alkyl) precursors bearing Cp, Ind, and 3-Me_3Si-Ind segments exhibited very low catalytic activity to afford syndiotactic polystyrene. All electron-donating t Bu substituted complexes 4 a, 4 b, and 4 c showed very high activity and perfect syndiotactivity(rrrr > 99%), producing high molecular weight polystyrene(up to 54.1 × 10~4) with relatively narrow molecular distribution(PDI = 1.28-2.49).

关键词： Polystyrene Syndiotactic Rare-earth metal Constrained-geometry configuration

Numerical estimate of multi-species ion sound speed of Langmuir probe interpretations in the edge plasmas of Wendelstein 7-X

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Plasma Science and Technology 2020年第8期22卷 63-70页

作者： J COSFELD P DREWS B BLACKWELL M JAKUBOWSKI H NIEMANN D zhang Y FENG the Wendelstein-X Team Forschungszentrum Jülich GmbH Institut für Energie-und Klimaforschung-PlasmaphysikPartner of the Trilateral Euregio Cluster(TEC)52425 JülichGermany JARA-HPC Jülich Supercomputing CentreForschungszentrum Jülich GmbH52425 JülichGermany Australian National University Acton ACT2601 CanberraAustralia Max-Plank-Insitut für Plasmaphysik 17491 Greifswald/85748 GarchingGermany

The recently modified EMC3-EIRENE code package has been widely applied as an edge-plasma analysis tool and resulted in successful validation against various measured trends seen in stellarator and tokamak plasma *** has been shown that the code package applied for Wendelstein 7-X(W7-X)discharges in the interpretive mode can assess the impact of impurity effects on the electron density,measured by a set of Langmuir *** particular the spatial quantification of impurities and effects from the effective charge state Zeff and effective mass meff,which are non-trivial to record by diagnostics,were *** results showed that earlier assumptions of the effective charge-state distribution and effective mass for reported Langmuir probe measurements must be ***,reprocessing these measurements with code-interpreted spatial profiles of the effective charge state and effective mass led to an overall improved physical consistency.

关键词： Wendelstein 7-X plasma-wall interaction numerical-diagnostics EMC3-EIRENE

In situ characterization of vacancy ordering in Ge-Sb-Te phase-change memory alloys

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Fundamental Research 2024年第5期4卷 1235-1242页

作者： Ting-Ting Jiang Xu-Dong Wang Jiang-Jing Wang Han-Yi zhang Lu Lu Chunlin Jia Matthias Wuttig Riccardo Mazzarello Wei zhang En Ma Center for Alloy Innovation and Design(CAID) State Key Laboratory for Mechanical Behavior of MaterialsXi'an Jiaotong UniversityXi'an 710049China Institute of Physics IA RWTH Aachen UniversityAachen 52074Germany The School of Microelectronics State Key Laboratory for Mechanical Behavior of MaterialsXi'an JiaotongUniversityXi'an 710049China JARA-FIT and JARA-HPC RWTH Aachen UniversityAachen 52056Germany Peter Grünberg Institute(PGI 10) Forschungszentrum Jülich GmbHJülich 52425Germany Department of Physics Sapienza University of RomeRome 00185Italy

Tailoring the degree of structural disorder in Ge-Sb-Te alloys is important for the development of non-volatile phase-change memory and neuro-inspired *** crystallization from the amorphous phase,these alloys form a cubic rocksalt-like structure with a high content of intrinsic *** thermal annealing results in a gradual structural transition towards a layered structure and an insulator-to-metal *** this work,we elucidate the atomic-level details of the structural transition in crystalline GeSb_(2)Te_(4) by in situ high-resolution transmission electron microscopy experiments and ab initio density functional theory calculations,providing a comprehensive real-time and real-space view of the vacancy ordering *** also discuss the impact of vacancy ordering on altering the electronic and optical properties of GeSb_(2)Te_(4),which is relevant to multilevel storage *** phase evolution paths in Ge-Sb-Te alloys and Sb_(2)Te_(3)are illustrated using a summary diagram,which serves as a guide for designing phase-change memory devices.

关键词： Phase-change materials Vacancy ordering Structural transition Metavalent bondingin situ TEM

Complex hexagonal close-packed dendritic growth during alloy solidification by graphics processing unit-accelerated three-dimensional phase-field simulations:demo for Mg–Gd alloy

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Rare Metals 2023年第10期42卷 3468-3484页

作者： Sheng-Lan Yang Jing Zhong Kai Wang Xun Kang Jian-Bao Gao Jiong Wang Qian Li Li-Jun zhang State Key Lab of Powder Metallurgy Central South UniversityChangsha410083China Institute for Energy and Climate Research IEK-2Forschungszentrum Jülich52425JülichGermany International Center for Materials Nanoarchitechonics(WPI-MANA) National Institute for Materials Science(NIMS)Ibaraki305-0044Japan Graduate School of Chemical Science and Engineering Hokkaido UniversitySapporo060-0808Japan National Engineering Research Center for Magnesium Alloys Chongqing UniversityChongqing400044China

In this study,insights into the effect of interfacial anisotropy on a complex hexagonal close-packed(hcp) dendritic growth during alloy solidification were gained by graphics processing unit(GPU)-accelerated three-dimensional(3D) phase-field simulations,as demonstrated for a Mg-Gd *** anisotropic phasefield model with finite interface dissipation was developed by incorporating the contribution of the anisotropy of interfacial energy into the total free energy *** modified spherical harmonic anisotropy function was then chosen for the hcp *** GPU parallel computing algorithm was implemented in the present phase-field model,and a corresponding code was developed in the compute unified device architecture parallel computing *** tests indicated that the calculation efficiency of a single TESLA V100 GPU could be~80times that of open multi-processing(OpenMP) with eight central processing unit *** coupling the phase-field model with reliable thermodynamic and interfacial energy descriptions,the 3D phase-field simulation of α-Mg dendritic growth in the Mg-6Gd(in wt%) alloy during solidification was *** two-dimensional dendrite morphologies were revealed by cutting the simulated 3D dendrite along different crystallographic *** sixfold equiaxed and butterflied microstructures observed in experiments were well reproduced.

关键词： Interfacial anisotropy Dendrite solidification Phase-field model Graphics processing unit(GPU) Mg–Gd

Enforced Freedom: Electric-Field-Induced Declustering of Ionic-Liquid Ions in the Electrical Double Layer

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Energy & Environmental Materials 2020年第3期3卷 414-420页

作者： Yufan zhang Ting Ye Ming Chen Zachary A.H.Goodwin Guang Feng Jun Huang Alexei A.Kornyshev IEK-13 Institute of Energy and Climate ResearchForschungszentrum Jülich GmbHJülich 52425Germany State Key Laboratory of Coal Combustion School of Energy and Power EngineeringHuazhong University of Science and Technology(HUST)Wuhan 430074China Department of Chemistry Imperial College LondonMolecular Sciences Research HubWhite City CampusLondon W120BZUK Department of Physics Imperial College LondonSouth Kensington CampusLondon SW72AZUK Thomas Young Centre for Theory and Simulation of Materials Imperial College LondonSouth Kensington CampusLondon SW72AZUK Hunan Provincial Key Laboratory of Chemical Power Sources College of Chemistry and Chemical EngineeringCentral South UniversityChangsha 410083China

Ions in the bulk of solvent-free ionic liquids bind into ion pairs and *** competition between the propensity of ions to stay in a bound state,and the reduction of the energy when unbinding in electric field,determines the portion of free ions in the electrical double *** present the simplest possible mean-field theory to study this effect."Cracking"of ion pairs into free ions in electric field is accompanied by the change of the dielectric response of the ionic *** predictions from the theory are verified and further explored by molecular dynamics simulations.A particular finding of the theory is that the differential capacitance vs potential curve displays a bell shape,despite the low concentration of free charge carriers,because the dielectric response reduces the threshold concentration for the bell-to camelshape *** presented theory does not take into account overscreening and oscillating charge distributions in the electrical double *** in spite of the simplicity of the model,its findings demonstrate a clear physical effect:a preference to be a charged monopole rather than a dipole(or higher order multipole)in strong electric field.

关键词： differential capacitance ion pairs ionic liquids unbinding

Experimental study on age and gender differences in microscopic movement characteristics of students

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Chinese Physics B 2021年第9期30卷 633-642页

作者： Jiayue Wang Maik Boltes Armin Seyfried Antoine Tordeux Jun zhang Wenguo Weng Public Order School People's Public Security University of ChinaBeijing 100038China Center for Capital Social Safety People's Public Security University of ChinaBeijing 100038China Public Security Behavioral Science Laboratory People's Public Security University of ChinaBeijing 100038China Institute for Advanced Simulation Forschungszentrum JülichJülich 52428Germany Faculty of Architecture and Civil Engineering University of WuppertalWuppertal 42119Germany School of Mechanical Engineering and Safety Engineering University of WuppertalWuppertal 42119Germany State Key Laboratory of Fire Science University of Science and Technology of ChinaHefei 230026China Institute of Public Safety Research Department of Engineering PhysicsTsinghua UniversityBeijing 100084China

Campus security has aroused many concerns from the whole *** is one of the most frequent and influential accidents in *** on pedestrian dynamics especially focusing on students are essential for campus security,which are helpful to improve facility design and emergency evacuation *** this paper,primary and middle school students were recruited to participate in the single-file *** microscopic movement characteristics,including walking speed,headway,gait characteristics(step length,step frequency and swaying amplitude)and their relations were *** and gender differences in the headway-speed diagram and space requirements were analyzed by statistical *** results indicated that the impacts of age and gender were *** were three stages for the influence of gender on the headway-speed diagram for both age *** impacts on students'space requirements were consistent for different age and gender *** the impacts of age and gender on free-flow speed were affected by each *** to the connection of walking speed and gait characteristics,the comparisons of gait characteristics between different ages and genders were performed to understand the corresponding differences in speed more *** results showed that differences in step length and swaying amplitude between males and females were significant for both age *** effect of gender on step frequency was significant for primary *** for middle school students,whether gender had significant impact on step frequency was not clear here because of the large ***,the influence of age on gait characteristics changed with gender.

关键词： campus security microscopic movement characteristics pedestrian dynamics single-file movement experiments