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类雇员——法制史、法教义学及法政治学上的思考

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法治现代化研究 2024年第1期8卷 179-191页

作者： [德]沃尔夫冈·赫罗马德卡李比特(译) 不详南京师范大学法学院中国法治现代化研究院

在发表《雇员概念及劳动法》(NZA 1997,569)这一基础理论性文章后,笔者又撰文对类雇员制度进行进一步探讨。从“类雇员”法律历史渊源到法教义学基础的长期发展最终形成该术语的定义。最后,笔者以相关法政治学上的思考作为结尾为本文画... 详细信息

在发表《雇员概念及劳动法》(NZA 1997,569)这一基础理论性文章后,笔者又撰文对类雇员制度进行进一步探讨。从“类雇员”法律历史渊源到法教义学基础的长期发展最终形成该术语的定义。最后,笔者以相关法政治学上的思考作为结尾为本文画上句号。

关键词：法教义学法制史法政治学理论性文章类雇员劳动法历史渊源

New approaches for brazing temperature sensitive materials

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China Welding 2014年第3期23卷 21-25页

作者： wolfgang TiUmann Chunlai Liu Lukas Wojarski Institute of Materials Engineering Technical University of Dortmund

PVD deposited copper interlayers as filler materials were used in order to manufacture TLP brazed magnesium joints. The microstructure and interface characteristics of the overlap joints were investigated by optical microscopy, scanning electron microscope with energy dispersive spectrometer and tensile testing. Sound brazed joints could be achieved. The dwell time is the main factor to control the thickness of the reaction layer. It was shown that the deposited copper filler metal clearly reacted with the magnesium substrate , resulting in the formation of a magnesium solid solution （Mg） with different amount of copper, aluminum and zinc as well as Mg2Cu phases. With the progressing diffusion, the formation of intermetaUic compounds was suppressed and the hardness distribution in the brazing seam homogenized. The joints fractured at the interface, and the maximum average tensile shear strength of overlap joints reached 85 MPa.

关键词： brazing TLP diffusion magnesium

CONVEXITY AND BERNSTEIN POLYNOMIALS ON k-SIMPLOIDS

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Acta Mathematicae Applicatae Sinica 1990年第1期6卷 50-66页

作者： wolfgang DAHMEN CHARLES A.MICCHELLI Institut fur Mathematik Ⅲ Freie Universitat Berlin Arnimallee 2-61000 Berlin(West)33GermanyIBM T.J.Watson Research CenterP.O.Box 218Yorktown HeightsN.Y.10598U.S.A.

This paper is concerned with Bernstein polynomials on k-simploids by which we mean a crossproduct of k lower dimensional simplices. Specifically, we show that if the Bernstein polynomials ofa given function f on a k-simploid form a decreasing sequence then f+l, where l is any correspondingtensor product of affine functions. achieves its maximum on the boundary of the k-simploid. Thisextends recent results in [1] for bivariate Bernstein polynomials on triangles. Unlike the approachused in [1] our approach is based on semigroup techniques and the maximum principle for secondorder elliptic operators. Furthermore, we derive analogous results for cube spline surfaces.

关键词： Tensor Product Recent Result Maximum Principle Cross Product Analogous Result

Holocene Climate Evolution of the Ugii Nuur Basin, Mongolia

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Advances in Atmospheric Sciences 2008年第6期25卷 986-998页

作者： wolfgang SCHWANGHART Brigitta SCHTT Michael WALTHER Department of Environmental Sciences University of Basel Institute of Geographical Sciences Freie Universitt Berlin Mongolian Landscape Research Centre National University of Mongolia

In order to evaluate the Holocene palaeoenvironmental evolution of the Ugii Nuur basin, central Mongolia, investigations on chemical and mineralogical properties of lacustrine sediments were carried out on a 630 cm sediment core from lake Ugii Nuur. The interpretation of the record is based on a principal component analysis （PCA） of the elemental composition of the samples. The results show that lacustrine deposition started at 10.6 kyr BP. Low lake level conditions were identified during the Early Holocene （10.6-7.9 kyr BP）. The Mid Holocene （7.9-4.2 kyr BP） was characterized by generally higher lake levels and thus higher moisture supply, but it experienced strong climatic fluctuations. Arid conditions prevailed from 4.2-2.8 kyr BP and were followed by a stable, more humid phase until today.

关键词： lake sediments palaeoclimate Central Asia Mongolia Holocene

The chromosome as a dynamic structure of the cell nucleus

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Cell Research 1993年第1期3卷 1-9页

作者： wolfgang Hennig Deparment of Molecular and Developmental Genetics University of Nijmegen Faculty of Science Toernooiveld The Netherlands Maχ-PlanckGuest Laboratory Shanghai Institute of Cell Biology Academia Sinica Shanghai China

Our view of eukaryotic chromosomes is still very much dictated by the classic ideas of geneticists and cytologists considering the chromosome just as a vehicle for genes. This one-sided view of chromosomes may have been strongly influenced by the many cytological observations made on polytene chromosomes. They, in particular, revealed that the activation of genes for transcription is accompanied by local decondensation of the chromosome as it becomes evident in the formation of puffs in polytene chromosomes. The studies of chromosomes have for many years been focused on the relationship between genes and bands or interbands as they are seen in polytene chromosomes (or in the supposed equivalents, the chromomeres, of meiotic prophase chromosomes). This has yielded much fruitful informations such as the first direct evidence for the relationship between differential gene activity and cellular differentiation by the demonstration by Clever that steroid hormones directly regulate gene activity at the chromosomal level.

关键词： Cell The chromosome as a dynamic structure of the cell nucleus cell

Multi-cell Monte Carlo method for phase prediction

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npj Computational Materials 2019年第1期5卷 83-87页

作者： Changning Niu You Rao wolfgang Windl Maryam Ghazisaeidi Department of Materials Science and Engineering The Ohio State UniversityColumbusOH 43210USA Department of Physics The Ohio State UniversityColumbusOH 43210USA QuesTek Innovations LLC EvanstonIL 60201USA

We propose a Multi-Cell Monte Carlo algorithm,or(MC)2,for predicting stable phases in chemically complex crystalline *** algorithm takes advantage of multiple cells to represent possible phases,while eliminating the size and concentration restrictions in the previous *** atomic transfer among cells is achieved via the application of the lever rule,where an assigned molar ratio virtually controls the percentage of each cell in the overall simulation,making(MC)2 the first successful algorithm for simulating phase coexistence in crystalline *** the application of this method,all energies are directly computed via density functional theory *** test the method by successful prediction of the stable phases of known binary *** then apply the method to a quaternary high-entropy *** method is particularly powerful in predicting stable phases of multicomponent systems,for which phase diagrams do not exist.

关键词： prediction phase method

Improvement of center segregation in high-carbon steel billets using soft reduction

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Journal of University of Science and Technology Beijing 2006年第6期13卷 490-496页

作者： Wenjun Wang Xionggang Hu Linxin Ning Raimund Bülte wolfgang Bleck Institute of Ferrous Metallurgy RWTH Aachen University Intzestrasse 1 52072 Aachen Germany Shougang Group Research Institute Beijing 100041 China

Center segregation is the main reason for cup fracture of high-carbon wire rod during drawing. Therefore, to continuously produce cast billets with very low center segregation is an important objective. The soft reduction technology is considered to be an effective method to minimize center segregation. To elucidate the effect of soft reduction on the internal quality of high-carbon steel billets, soft reduction was applied with different solid fractions in the core area of billets in a laboratory casting machine. A coupled temperature/displacement finite element model was developed to calculate the solid fraction using the commercial software ABAQUS. Center segregation, center porosity, homogeneity of elements, and equiaxed crystal zone were obviously improved by applying soft reduction, especially when the solid fraction was less than 1.0. The optimal results were obtained when the solid fraction was approximately 0.9.

关键词： steel 100Cr6 centre segregation soft reduction finite element model internal cracks

Mechanically induced phase transformation of zinc sulfide

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Particuology 2015年第1期13卷 1-10页

作者： Cornelia Damm Patrick Armstrong Christian Roβkopf Stefan Romeis wolfgang Peukert University Erlangen-Nuremberg Institute of Particle Technology

Molecular dynamics （MD） simulations of the consecutive compression-decompression cycles ot hexagonal zinc sulfide （wurtzite） nanoparticles predict an irreversible phase transformation to the cubic *** phase transformation commences at the contact area between the particle and the inden- ter and proceeds with the number of compression cycles. Dislocations are visible for a particle size above 5nm. Results from wet grinding and dry powder compression experiments on a commercial wurtzite pigment agree qualitatively with MD simulation predictions. X-ray diffraction patterns reveal that the amount of cubic polymorph in the compressed samples increases with pressure applied to the powder. In comparison with powder compression, wet milling leads to a more pronounced phase transformation. This occurs because the particles are exposed to a large number of stress events by collision with the grinding media, which leads to the formation of defects and new surface crystallites by particle fracture. According to the MD simulations, phase transformation is expected to occur preferentially in surface crystallites because they experience the highest mechanical load. Because of the phase transformation, the wet ground and compressed samples exhibit a lower photo- luminescence intensity than the feed material. In comparison with powder compression, milling reduces the photoluminescence intensity more substantially. This occurs because a higher defect concentration is formed. The defects contribute to the phase transformation and photoluminescence quenching.

关键词： Polymorph transformationZinc sulfide Molecular dynamics simulation Wet milling Powder compression

Invasion of Prosopis juliflora and its effects on soil physicochemical properties in Afar region,Northeast Ethiopia

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International Soil and Water Conservation Research 2021年第4期9卷 631-638页

作者： Wakshum Shiferaw Sebsebe Demissew Tamrat Bekele Ermias Aynekulu wolfgang Pitroff Arba Minch University College of Agricultural SciencesNatural Resources ManagementP.O.Box 21Arba MinchEthiopia Addis Ababa University College of Natural SciencesPlant Biology and Biodiversity ManagementP.O.Box 3434Addis AbabaEthiopia The World Agroforestry Centre(ICRAF) UN AvenueP.O.Box 30677NairobiKenya College of Agriculture Food and Natural ResourcesUniversity of MissouriColumbiaUSA

Woody species within pastures and savannas are often associated with‘resource islands’characterized by higher fertility under canopies *** aims of this study were to evaluate(1)the effects of Prosopis juliflora on some soil physicochemical properties and(2)the impacts of Prosopis invasion on soil *** soil physicochemical analysis,a total of 104 soil samples from Teru and Yalo Districts were *** soil samples were collected from soil depths of 0-15 cm and 15-30 cm in Prosopis invaded and non-invaded open grazing *** of Prosopis had significantly affected soil pH,exchangeable Na^(+),water soluble Ca^(2+)+Mg^(2+),water soluble Na^(+),and exchangeable sodium percentage in Teru and Yalo Districts(p<0.05).The invasion of Prosopis significantly increased soil pH(1.5%),but decreased exchangeable Na^(+)(24.2%),exchangeable sodium percentage(21.6%),and water soluble Ca^(2+)+Mg^(2+)(39.9%)than non-invaded *** content of Prosopis invaded lands was higher by 19%than non-invaded ***,sand content of soil was higher under non-invaded lands by 5.6%than Prosopis invaded *** results indicated that invasion of Prosopis had positive effects on physicochemical properties and thus conducive for cereal crops and forages.

关键词： Phrase(s):invasion Open grazing lands Prosopis Rangelands reclamation Soil properties