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Journal of Integrative Plant Biology 2009年第5期51卷 433-436页

作者： Hans Schnyder monika Kavanova C.Jerry Nelson lehrstuhl für grünlandlehre Technische Universitt München85350 Freising-WeihenstephanGermany Department of Cell & Developmental Biology John Innes Centre Division of Plant Sciences University of Missouri

Hu and Schmidhalter （2008） conducted a study with wheat seedlings growing in saline and non-stressed （control） conditions with the aim of identifying and quantifying the cellular basis for the reduction in leaf growth. We applaud their goals as salinity is an important issue for plant ecology and food production; however, we have concerns about the methodology used and the subsequent conclusJons that are drawn.

关键词： Kinematic Analysis of Leaf growth in grasses cell length

finite cell method compared to h-version finite element method for elasto-plastic problems

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Applied mathematics and mechanics(English Edition) 2014年第10期35卷 1239-1248页

作者： A.ABEDIAN J.PArVIZIAN A.DStEr E.rANK Department of mechanical Engineering Daneshpajoohan Higher Education Institute Department of mechanical Engineering Isfahan University of Technology Numerische Strukturanalyse mit Anwendungen in der Schiffstechnik (m-10) Technische Universitt Hamburg-Harburg lehrstuhl fr Computation in Engineering Fakultt fr Bauingenieur-und Vermessungswesen Technische Universitt Mnchen

the finite cell method （fCm） combines the high-order finite element method （fEm） with the fictitious domain approach for the purpose of simple meshing. In the present study, the fCm is used to the Prandtl-reuss flow theory of plasticity, and the results are compared with the h-version finite element method （h-fEm）. the numerical results show that the fCm is more efficient compared to the h-fEm for elasto-plastic problems, although the mesh does not conform to the boundary. It is also demonstrated that the fCm performs well for elasto-plastic loading and unloading.

关键词： finite cell method (fCm) h-version finite element method (h-fEm),Prandtl-reuss quadtree octree

tHE EXAmINAtION Of tUrBULENCE mODELING WItH LES DAtABASE

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Applied mathematics and mechanics(English Edition) 1994年第11期15卷 1047-1053页

作者：苏铭德 1. Qinghua university Beijing 2. lehrstuhl für fluidsmechanik technische universit?t münchen Germany

In this paper the database obtained from LES is used to examine the algebraicturbulence model in Demuren and rodi’s work. the results show that the prediction ofnormal reynolas stresses and turbulence energy by means of turbulence modeling isbetter than that of shear reynolde stresses. the comparison shows the LES methodcan be used to examine turbulence modelling.

关键词： turbulence LES (large eddy simulation) turbulence model

Climate and anthropogenic drivers of changes in abundance of C4 annuals and perennials in grasslands on the mongolian Plateau

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grassland research 2022年第2期1卷 131-141页

作者： Hao Yang Karl Auerswald Xiaoying Gong Hans Schnyder Yongfei Bai lehrstuhl für grünlandlehre Technische Universität MünchenFreisingGermany School of Geographical Sciences Fujian Normal UniversityFuzhouChina State Key Laboratory of Vegetation and Environmental Change Institute of BotanyThe Chinese Academy of SciencesBeijingChina College of resources and Environment University of Chinese Academy of SciencesBeijingChina

Background:C4 plants have increased substantially during the past several decades in the grasslands of the mongolian Plateau due to regional ***,we explore how the patterns of abundances of C4 annuals and C4 perennials change over space and ***:A total of 280 sites with C4 plants were surveyed in four types of grasslands in 9 *** relative biomasses of C4 plants(PC4),C4 annuals(PA4),and C4 perennials(PP4)were *** equation modeling was used to analyze the drivers of changes in PA4 and ***:At the regional scale,PA4 on average was 11%(±19%,SD)and PP4 was 13%(±19%,SD).Spatially,C4 annuals dominated the C4 communities within an east–west belt region along 44°N and tended to spread toward northern latitudes(about 0.5°)and higher altitudes in the east mountainous *** abundance of C4 annuals decreased,while that of C4 perennials *** patterns of C4 annuals and C4 perennials were mainly controlled by temperature,growing season precipitation,and dynamics between the two life ***:C4 annuals exhibited competitive advantages in normal and wet years,while C4 perennials had competitive advantages in dry *** as a main human disturbance increased C4 annuals,but had no significant effect on C4 perennials.

关键词： C4 annuals and perennials C4 plants grazing growing season precipitation mongolian Plateau temperature

mEASUrEmENt Of ADHESION fOrCES IN AIr WItH tHE VIBrAtION mEtHOD

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China Particuology 2005年第1期3卷 3-9页

作者： Siegfried ripperger Konrad Hein lehrstuhl für mechanische Verfahrenstechnik Technische Universit(a|¨)t Kaiserslautern67653 Kaiserslautern Germany lehrstuhl für mechanische Verfahrenstechnik Technische Universit(a|¨)t Dresden 01062 Dresden Germany

the vibration method represents a practical method for the measurement of adhesion forces and adhesion force distributions. this method causes sinusoidally alternating stresses and yields detachment and contact forces between particles and substrate of the same order of magnitude. Alternating contact forces of the vibration method can cause an adhesion force intensification through flattening of asperities. the measuring principle of the vibration method and the analysis of experimental results are described in the article. Normal adhesion forces (pull-off forces) are measured using the vibration method and the colloidal probe technique. the results of both methods show good agreement for small particle sizes. the influence of the detachment force direction is shown by comparing tangential and normal adhesion forces measured using particle reentrainment in a turbulent air flow and the vibration method, respectively. the surface roughness of the substrate and the relative humidity are shown to significantly influence the measured adhesion forces. for the calculation of the adhesion forces, an approach by rabinovich was combined with approximations of plastic micro asperity flattening. the rabinovich approach accounts for roughness effects on the van der Waals force by incorporating the rms roughness of the interacting surfaces, rms-values of the particles and substrates were measured with atomic force microscopy at different scanning areas.

关键词： adhesion force vibration method roughness

Hop-induced formation of ethyl esters in dry-hopped beer

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food Production, Processing and Nutrition 2020年第1期2卷 179-185页

作者： Sabrina Brendel thomas Hofmann michael granvogl lehrstuhl für Lebensmittelchemie und molekulare Sensorik Technische Universität MünchenWissenschaftszentrum Weihenstephan für ErnährungLandnutzung und UmweltLise-Meitner-Straße 3485354 FreisingGermany Institut für Lebensmittelchemie Fg.Lebensmittelchemie und Analytische Chemie(170a)Universität HohenheimFakultät für NaturwissenschaftenGarbenstraße 2870599 StuttgartGermany

fruity smelling esters play an important role for the aroma of hops and beer and they have been characterized as key aroma compounds in different hop *** on the transfer of hop-derived compounds into beer during dry-hopping showed calculated transfer rates of different ethyl esters far above 100%,leading to the assumption that these esters must be newly *** investigate this formation,dry-hopping was imitated in water to eliminate the influence of the beer matrix on the formation of these ***,the formation of ethyl esters of 2-methylbutanoic acid,3-methylbutanoic acid,and methylpropanoic acid,induced by the addition of hops,was *** approaches inhibiting enzyme activities and experiments with different hop extracts might lead to the assumption that enzymes are involved in the formation of these esters,beside possible transesterification.

关键词： Hops Dry-hopping Beer Ethyl esters Aroma formation radicals Enzymes

Disposition and metabolism of 1 -Nitropropane in rats and Chimpanzees

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Biomedical and Environmental Sciences 1989年第3期2卷 249-264页

作者： mArgrEt HAAS-JOBELIUS frIEDHELm KOrtE f.COULStON Gesellschaft Gesellschaft technische universit t münchen Institut für Chemie lehrstuhl für kologische Chemie Am L wentor D-8050 freisingWeihenstephan federal republic of Germany and White Sands research Center 2512 Christina Place Alamogordo New mexico 88310 für Strahlen-und Umweltforschung mbH münchen Institut für kologische Chemie Ingolst dter Landstrasse 1 D-8042 Neuherberg federal republic of Germany

the metabolic fate of 1 -nitropropane (1-NP) has not been previously reported. In this study male rats and chimpanzees were given single doses of 40 mg/kg ip and 5 mg/kg iv 1-[1-^(14)C]NP, respectively. the quantitative extent of urinary and fecal elimination was similar in both species. the rats excreted 16.5% ofthedosein urine and 1.7% in feces. for chimpanzees the respective values were 14.8 and 1.2%. Experiments with rats demonstrated that the major route of elimination was by exhalation. With a total elimination via the lungs of 72.6%, rats expired 10.3% of the dose as unchanged 1-NP. five polar metabolites were isolated from the urine of chimpanzees. the two major metabolites were identified as 3-hydroxypropionic acid and 7V-methyl-N-2-(methylsulfinyl)ethylpropionic acid amide (NmPA). Both substances were also excreted in rat urine. the two identified metabolites indicate that 1-NP was degraded to propionic acid, part of which was modified to 3-hydroxypropionic acid or NmPA. A hypothetical pathway for the biochemical generation of NmPA is suggested.(c)1989 Academic Press, Inc.

关键词： ppm Nitropropane in rats and Chimpanzees Disposition and metabolism of 1

Efficient and stable ruddlesden-Popper layered tin-based perovskite solar cells enabled by ionic liquid-bulky spacers

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Science China Chemistry 2021年第9期64卷 1577-1585页

作者： Jian Qiu Yuexin Lin Xueqin ran Qi Wei Xingyu Gao Yingdong Xia Peter müller-Buschbaum Yonghua Chen Key Laboratory of flexible Electronics(KLOfE)&Institution of Advanced materials(IAm) Nanjing Tech University(NanjingTech)Nanjing211816China frontiers Science Center for flexible Electronics Xi’an Institute of Flexible Electronics(IFE)and Xi’an Institute of Biomedical Materials&EngineeringNorthwestern Polytechnical UniversityXi’an710072China Shanghai Synchrotron radiation facility Shanghai Institute of Applied PhysicsChinese Academy of SciencesShanghai201204China lehrstuhl für funktionelle materialien Physik DepartmentTechnische Universität München85748GarchingGermany Heinz maier-Leibnitz Zentrum(mLZ) Technische Universität München85748GarchingGermany

the crucial component,bulky spacers,in two-dimensional ruddlesden-Popper(2 DrP)layered tin(Sn)perovskites are highly limited by halide ammonium salts,leading to the insufficient control of complex crystallization process due to the limited interaction between bulky spacers and 2 DrP perovskite ***,we report an ionic liquid-bulky spacer,butylammounium acetate(BAAc O),for constructing efficient and stable 2 DrP Sn-based perovskite solar cells(PSCs).In contrast to the traditional halide ammonium bulky spacer,butylammounium iodide(BAI),the Ac O^(-)-functional group in BAAc O has a strong interaction with formamidine ions(fA^(+))and Sn2+.the inter-component interaction allows the formation of controllable intermediates for the favorable growth of smooth,dense,and highly oriented perovskite films.A PSC with power conversion efficiency of 10.36%(7.16%for BAI)is achieved,which is the highest report,along with improved stability with~90%retained after~600 h storage in N_(2) atmosphere without any encapsulation.

关键词： lead-free ruddlesden-Popper phase Sn-based perovskite solar cells ionic liquid-bulky spacer crystallization kinetic control

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Soil phosphorus bioavailability assessed by XANES and Hedley sequential fractionation technique in a glacier foreland chronosequence in Gongga mountain, Southwestern China

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Science China Earth Sciences 2014年第9期57卷 1860-1868页

作者： WU YanHong Jrg PrIEtZEL ZHOU Jun BING HaiJian LUO Ji YU Dong SUN ShouQin LIANG JianHong SUN HongYang Key Laboratory of mountain Surface Processes and Ecological regulation Institute of Mountain Hazards and EnvironmentChinese Academy of Sciences technische universitt münchen Lehrstuhl für BodenkundeD-85354 Freising Germany university of Chinese Academy of Sciences

the primary productivity of terrestrial ecosystems is influenced by soil phosphorus bioavailability, which depends largely on chemical fractions of phosphorus. the sequential fractionation technique developed by Hedley et al. or its subsequent modification is a well-known method to determine soil phosphorus forms. Hedley sequential fractionation technique separates the phosphorus into fractions based on their different chemical solubilities in extractants with certain chemical properties. recently, synchrotron-based X-ray absorption near edge structure(XANES) spectroscopy has been employed to measure soil phosphorus species directly and non-invasively. the XANES method provides information concerning local structure and chemical information of target elements at a molecular level. thus, it can distinguish phosphorus fractions bound by metal oxides or hydroxides(such as fe, Al, and Ca). In this present work, the phosphorus speciation of topsoil along a glacial foreland chronosequence in Gongga mountain is determined using these two methods. the changes in soil phosphorus bioavailability along the 120-year-old chronosequence are assessed based on comparisons of the results obtained by these two methods. the results indicate that Hedley sequential fractionation technique shows a greater ability to determine soil bioavailable phosphorus(resin-P and NaCHO3-P), while XANES is effective in distinguishing phosphorus bound by metal compounds. In the chronosequence, Ca- and Al-bound phosphorus were derived mainly from primary minerals, whose phosphorus contents decreased within 120 years of moraine weathering and soil development. the content of soil bioavailable phosphorus increased rapidly after 30 years since deglaciation. the increasing phosphorus bioavailability promoted the colonizing and primary succession vegetation.

关键词： soil phosphorus forms Hedley sequential fractionation technique XANES Hailuogou

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Emission from quantum-dot high-β microcavities: transition from spontaneous emission to lasing and the effects of superradiant emitter coupling

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Light(Science & Applications) 2017年第1期6卷 638-645页

作者： Sören Kreinberg Weng W Chow Janik Wolters Christian Schneider Christopher Gies frank Jahnke Sven Höfling martin Kamp Stephan reitzenstein 无 Institut für festkörperphysik Technische Universität BerlinBerlin 10623Germany Sandia National Laboratories AlbuquerqueNM 87185-1086USA lehrstuhl für technische Physik Universität WürzburgWürzburg 97074Germany School of Physics and Astronomy University of St AndrewsSt Andrews KY169SSUK Institute for theoretical Physics University of BremenBremen 28334Germany

measured and calculated results are presented for the emission properties of a new class of emitters operating in the cavity quantum electrodynamics *** structures are based on high-finesse GaAs/AlAs micropillar cavities,each with an active medium consisting of a layer of InGaAs quantum dots(QDs)and the distinguishing feature of having a substantial fraction of spontaneous emission channeled into one cavity mode(highβ-factor).this paper demonstrates that the usual criterion for lasing with a conventional(lowβ-factor)cavity,that is,a sharp non-linearity in the input–output curve accompanied by noticeable linewidth narrowing,has to be reinforced by the equal-time second-order photon autocorrelation function to confirm *** paper also shows that the equal-time second-order photon autocorrelation function is useful for recognizing superradiance,a manifestation of the correlations possible in high-βmicrocavities operating with *** terms of consolidating the collected data and identifying the physics underlying laser action,both theory and experiment suggest a sole dependence on intracavity photon *** for this assertion comes from all our measured and calculated data on emission coherence and fluctuation,for devices ranging from light-emitting diodes(LEDs)and cavity-enhanced LEDs to lasers,lying on the same two curves:one for linewidth narrowing versus intracavity photon number and the other for g(2)(0)versus intracavity photon number.

关键词： coherence laser physics microlasers nanolasers optoelectronics photon statistics quantum dots quantum optics