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Vegetation cover and occurrence of salamanders in the western Mediterranean

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Integrative Zoology 2022年第3期17卷 456-467页

作者： Daniel ESCORIZA axel HERNANDEZ GRECO Institute of Aquatic EcologyUniversity of GironaGironaSpain Department of Environmental Sciences Faculty of Sciences and TechnicsUniversity Pasquale Paoli of CorsicaCorteFrance

The Mediterranean region possesses a rich diversity of salamanders,which also exhibit a high degree of ecological diversification.It is assumed that the presence of salamanders is dependent on the level of vegetation cover in terrestrial habitats,but the strength of this association is likely to vary among species.In this study,we investigated the patterns of habitat utilization for Mediterranean salamanders based on 589 records of 33 species.We tested the hypothesis that the association between salamander presence and vegetation density varies among genera or reproductive modes(i.***.terrestrial vs aquatic).The results show that vegetation cover has similar influences on terrestrial and aquatic groups but important differences are identified for lotic and lentic aquatic species.Our findings also indicate that the aquatic lotic,terrestrial,and small-body species deviate significantly from that expected from the background range of variation.

关键词： amphibian conservation habitat remote sensing salamander

利用第一性原理模拟研究Li和LiO_(2)的溶剂化结构和动力学及其在非水有机电解质溶剂中的转化

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Chinese Journal of Catalysis 2022年第11期43卷 2850-2857页

作者： Behnaz Rahmani Didar axel Groß 乌尔姆大学理论化学研究所德国乌尔姆乌尔姆赫尔姆霍兹研究所电化学储能德国乌尔姆

利用密度泛函理论计算和从头算分子动力学(AIMD)模拟研究了三种有机电解质中Li^(+)和LiO_(2)在O_(2)还原时的溶剂化、扩散和转化.这些过程对锂空气电池的性能至关重要.除详细研究溶剂化壳层结构外,还利用AIMD模拟推导了扩散率,并与Blue-... 详细信息

利用密度泛函理论计算和从头算分子动力学(AIMD)模拟研究了三种有机电解质中Li^(+)和LiO_(2)在O_(2)还原时的溶剂化、扩散和转化.这些过程对锂空气电池的性能至关重要.除详细研究溶剂化壳层结构外,还利用AIMD模拟推导了扩散率,并与Blue-Moon系综方法一起探索Li^(+)和O_(2)-形成LiO_(2)以及2LiO_(2)歧化为Li_(2)O_(2)+O_(2).通过对比模拟结果和气相计算结果,研究电解质对这些反应的影响,结果表明,对于参与这些反应的离子物种,电解质的影响更为显著.

关键词： Li-空气电池氧化锂氧还原密度泛函理论从头算分子动力学溶剂化扩散歧化

Active Nematodynamics on Curved Surfaces–The Influence of Geometric Forces on Motion Patterns of Topological Defects

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Communications in Computational Physics 2022年第3期31卷 947-965页

作者： Michael Nestler axel Voigt Institut fur wissenschaftliches Rechnen TU Dresden01062 DresdenGermany Center for Systems Biology Dresden(CSBD) Pfotenhauerstraße 10801307 DresdenGermany Cluster of Excellence Physics of Life(PoL) 01062 DresdenGermany

We derive and numerically solve a surface active nematodynamics model.We validate the numerical approach on a sphere and analyse the influence of hydro-dynamics on the oscillatory motion of topological defects.For ellipsoidal surfaces the influence of geometric forces on these motion patterns is addressed by taking into ac-count the effects of intrinsic as well as extrinsic curvature contributions.The numerical experiments demonstrate the stronger coupling with geometric properties if extrinsic curvature contributions are present and provide a possibility to tuneflow and defect motion by surface properties.

关键词： Topological active matter defect dynamics hydrodynamic coupling surfacefinite elements

Piecewise quadratic growth during the 2019 novel coronavirus epidemic

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Infectious Disease Modelling 2020年第1期5卷 681-690页

作者： axel Brandenburg Nordita KTH Royal Institute of Technology and Stockholm UniversitySE-10691 StockholmSweden

The temporal growth in the number of deaths in the COVID-19 epidemic is subexponential.Here we show that a piecewise quadratic law provides an excellent fit during the thirty days after the first three fatalities on January 20 and later since the end of March 2020.There is also a brief intermediate period of exponential growth.During the second quadratic growth phase,the characteristic time of the growth is about eight times shorter than in the beginning,which can be understood as the occurrence of separate hotspots.Quadratic behavior can be motivated by peripheral growth when further spreading occurs only on the outskirts of an infected region.We also study numerical solutions of a simple epidemic model,where the spatial extend of the system is taken into account.To model the delayed onset outside China together with the early one in China within a single model with minimal assumptions,we adopt an initial condition of several hotspots,of which one reaches saturation much earlier than the others.At each site,quadratic growth commences when the local number of infections has reached a certain saturation level.The total number of deaths does then indeed follow a piecewise quadratic behavior.

关键词： COVID-19 Coronavirus Epidemic SIR model Reactionediffusion equation

Buffered microclimate determines the presence of Salamandra corsica

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Journal of Forestry Research 2021年第3期32卷 1089-1093页

作者： Daniel Escoriza axel Hernandez GRECO Institute of Aquatic EcologyUniversity of Girona17071 GironaSpain Department of Environmental Sciences University Pasquale Paoli20250 CorteFrance

Numerous amphibian species occupy microhabitats with buffered thermal and moisture conditions,typically under forest canopies.Here,we assessed whether the insular endemic Salamandra corsica also uses this type of habitat,which could have important implications for its conservation.We used data loggers to record the air temperature and air humidity at 4 h intervals over a period of 2 years,at 13 stations with a confirmed presence of S.corsica.These data were compared with those recorded at Corsican weather stations and those generated by a climate model(WorldClim 2).The weather station data showed significant deviations from the probe data,by an average of-1.26℃(minimum temperature),+2.61℃(maximum temperature),and-0.04%(relative humidity).Similarly,the WorldClim 2 data showed significant deviations from the probe data,by an average of-2.49°C(minimum temperature)and+1.69℃(maximum temperature).These discrepancies refl ect the use of densely vegetated and topographically complex habitats by S.corsica,which reduce temperature fluctuations.Overall,our results highlight the importance of natural vegetal cover in the conservation of populations of this endemic salamander.

关键词： Fire salamander Island endemic Microclimate Probe Threatened species

杂化化合物(C_(7)H_(11)N_(2))_(2)[CdCl_(4)]·0.5H_(2)O的晶体结构、光谱表征和光学性质

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无机化学学报 2022年第9期38卷 1834-1842页

作者： Fatma Garci axel Klein Hammouda Chebbi Mohamed Faouzi Zid University of Tunis El Manar Faculty of Sciences of TunisLaboratory of MaterialsCrystal Chemistry and Applied ThermodynamicsTunisTunisia University of Cologne Faculty of Mathematics and Natural SciencesDepartment of ChemistryInstitute for Inorganic ChemistryCologneGermany University of Tunis Preparatory Institute for Engineering Studies of TunisTunisTunisia

开发了标题化合物(C_(7)H_(11)N_(2))_(2)[CdCl_(4)]·0.5H_(2)O(C_(7)H_(11)N_(2)=4-(二甲基氨基)吡啶鎓)的制备程序,并得到良好的收率和纯度。Cd离子在略微扭曲的四面体环境中与4个氯离子配位。晶体排列显示出层状结构,有机层和无机... 详细信息

开发了标题化合物(C_(7)H_(11)N_(2))_(2)[CdCl_(4)]·0.5H_(2)O(C_(7)H_(11)N_(2)=4-(二甲基氨基)吡啶鎓)的制备程序,并得到良好的收率和纯度。Cd离子在略微扭曲的四面体环境中与4个氯离子配位。晶体排列显示出层状结构,有机层和无机层交替排列,平行于(001)平面,位于x=n+1/2(n∈Z)。在晶体中,有机层和无机层通过C—H…Cl、C—H…O、N—H…Cl和N—H…O氢键相互作用连接。Hirshfeld表面分析和结构的指纹图表明分子堆积受氢键和π堆积的控制。UV-Vis漫反射光谱使我们能够用Tauc外推法确定具有半导体特性的3.596 eV的直接带隙。观察到的在562 nm处具有最大值的光致发光带归属于4-(二甲基氨基)吡啶鎓阳离子中的激发π-π*态。

关键词：氯镉(Ⅱ)配离子 4-二甲氨基吡啶鎓晶体结构 Hirshfeld表面分析光致发光

The future of underground spatial planning and the resulting potential risks from the point of view of mining subsidence engineering

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International Journal of Mining Science and Technology 2020年第1期30卷 93-98页

作者： Carolina Brücker axel Preuβe Institute for Mine Surveying Mining Subsidence Engineering and Geophysics in MiningRWTH Aachen UniversityWüllnerstr.2Aachen 52062Germany

The topic of ground movements in Germany has been studied extensively in the past,especially in the field of active mines.The active hard coal mines in Germany were finally shut down in 2018 and lignite mining is expected to take place only until 2038.The so-called long-term liabilities of the mine operators in Germany include,among other things,the long-term guarantee of stability and thus the monitoring of ground motion.So far,the economic use of underground mining in Germany was mainly the supply of raw materials.In the future,the underground storage of compressed air,methane or hydrogen will play an important role in renewable energy supply and climate change.Therefore,the underground storage space will become more important and the spatial planning is essential to ensure availability of safe underground openings for the various options of environmentally friendly energy storage.However,this renewed usage of underground openings may also bring new and sometimes unknown challenges of geomechanical influence.The aftermath of hard coal and lignite mining will be an increasing challenge in mining subsidence engineering.On the other hand,new possibilities due to underground spatial planning may lead to subsidence and/or heaving of the upper surface.

关键词： Mining Surveying Underground spatial planning Mining engineering Renewable energies

Use of the area of main influence to fix a relevant boundary for mining damages in Germany

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International Journal of Mining Science and Technology 2018年第1期28卷 79-83页

作者： Denise Müller axel Preusse Faculty of Georesources and Materials Engineering Institute for Mine Surveying Mining Subsidence Engineering and Geophysics in Mining RWTH Aachen University

In 2010, the fracking discussion in Germany caused a number of changes in German law, which came into force in 2016.Especially the production of gas had to be regulated.With the legislation amendment, the Subsidence-Area Mining Regulation has been revised, too.The changes expand the compensation of mining damages, especially to the extraction with drilling from the surface and underground storage.Although the Subsidence-Area Mining Regulation has been revised, the area of main influence(subsidence of 10 cm)remains to determine a relevant boundary for mining damages.The determination and prediction of this boundary above caverns are presented in this paper.In addition, further elements of ground movements and their relevance to mine damages are analyzed.The usage of the area of main influence to fix a relevant boundary for mining damages does not correspond to the relevant elements of ground movements.A limit for differences in subsidence(tilt) or horizontal changes in length should be preferred to describe the relevance of mining damages on buildings.Furthermore, this paper outlines the meaning of using the area of main influence to fix a relevant boundary for mining damages.

关键词： Ground movements Area of main influence Boundary for mining damages Subsidence-area mining regulation Subsidence detection Modeling above caverns

电催化中的表面电荷效应第2部分:铂的过氧化氢反应

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Chinese Journal of Catalysis 2022年第11期43卷 2837-2849页

作者： Jun Huang Victor Climent axel Groß Juan M.Feliu 乌尔姆大学理论化学研究所德国乌尔姆阿利坎特大学电化学研究所西班牙阿利坎特乌尔姆亥姆霍兹电化学储能研究所德国乌尔姆

固体催化剂表面电荷会影响其电催化活性.目前,科研人员主要关注的是表面电荷如何影响局部反应区中电势和离子浓度.本文以Pt(111)上的H_(2)O_(2)氧化还原反应为模型,利用从头算分子动力学模拟研究了Pt(111)-水界面的特殊表面电荷效应.Pt(... 详细信息

固体催化剂表面电荷会影响其电催化活性.目前,科研人员主要关注的是表面电荷如何影响局部反应区中电势和离子浓度.本文以Pt(111)上的H_(2)O_(2)氧化还原反应为模型,利用从头算分子动力学模拟研究了Pt(111)-水界面的特殊表面电荷效应.Pt(111)上的负表面电荷排斥反应物(H_(2)O_(2))的O-O键,使其远离电极表面,从而导致O-O键断裂的活化能更高.进一步建立了双电层微观动力学模型,定量解释了Pt(111)上H_(2)O_(2)氧化还原反应的pH活性依赖,尤其是电极电位降低时H_(2)O_(2)还原活性的异常抑制.还探讨了该表面电荷效应在不同电解质阳离子、溶液pH值、催化剂晶面和模型参数等情况下的适用性,与其他侧重于表面电荷对固定反应面上局部反应条件的影响机理研究不同,本文给出了一个通过表面电荷调节反应面位置的实例.

关键词：电催化表面电荷效应过氧化氢反应 Pt(111) 分子动力学模拟