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International Journal of Astronomy and Astrophysics 2014年第1期4卷 39-53页

作者： Dimitrie Olenici Alexander F. Pugach Ilie Cosovanu Cezar Lesanu Jean-Bernard Deloly Danil vorobyov Alexander Delets Stefan-Bogdan Olenici-Craciunescu Association AIRAMA Paris France Astronomical Obse.vatory Stefan cel Mare University of Suceava Suceava Romania leibniz-institut fur analytische wisenschaften-isas-e.v Dortmund Germany Main Astronomical Obse.vatory of National Academy of Sciences Kiev Ukraine Tomsa voda Technological Highschool Solca Romania

Several simultaneous obse.vations are presented of Syzygy effects during two solar eclipses, performed with torsinds and Foucault pendulums. The experiments/measurements were of a simple nature, conducted in several of places in Romania and Ukraine. It is shown that during Syzygy effects both the torsind and the Foucault pendulum exhibit specific reactions: the torsind’s disk is rotated, whereas the direction of the swing plane, the period, the eccentricity and the chirality of the ellipse of oscillation of the Foucault pendulum are all altered. We term all these perturbations “Syzygy effects” and found that they take place even when the devices are in locations where the eclipse is not visible and even when they are underground. An unusual time shifts?between the responses of the devices and the maximum phase of the eclipse is detected. The importance of simultaneous simple obse.vations of astronomical phenomena using these two devices of fundamentally different types is emphasized.

关键词： Paraconical Pendulum Antieclipse effect Torsind

Promotional nature of Sn on Pt/CeO_(2)for the oxidative dehydrogenation of propane with carbon dioxide

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Nano Research 2023年第5期16卷 6237-6250页

作者： Guo-Qing Yang Xing Ren vita A.Kondratenko Heng-Bo Zhang evgenii v.Kondratenko Zhong-Wen Liu Key Laboratory of Syngas Conversion of Shaanxi Province School of Chemistry&Chemical EngineeringShaanxi Normal UniversityXi’an 710119China leibniz-institut für Katalyse e.v Albert-Einstein-Strasse 29 aRostock 18059Germany

The oxidative dehydrogenation of propane with CO_(2)(CO_(2)-ODP)is a promising technology for the efficient production of propene in tandem with CO_(2)reduction to ***,the rational design of high-performance catalysts for this green process is still challenged by limited understanding of the nature of active sites and the reaction *** this work,the effects of SnO_(2) promoter on Pt/CeO_(2)activity and propene selectivity in CO_(2)-ODP are elucidated through varying the Sn/Pt molar *** the ratio increases,propane conversion gradually decreases,while the propene selectivity *** dependences are explained by increasing the electron density of Pt through the *** strength of this effect is determined by the Sn/Pt *** to the electronic changes of Pt,CO_(2)-ODP becomes more favorable than the undesired CO_(2)reforming of ***-modified Pt–O–Ce bonds are reasonably revealed as the active sites for CO_(2)-ODP occurring through a redox mechanism involving the activation of CO_(2)over oxygen vacancies at Sn-modified Pt and CeO_(2)*** atomic-scale understandings are important guidelines for purposeful development of high-performance Pt-based catalysts for CO_(2)-ODP.

关键词： oxidative dehydrogenation carbon dioxide supported PtSn ceria

Analysis of Mechanical Properties of Injection Molded Short Glass Fibre (SGF)/Calcite/ABS Composites

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Journal of Materials Science & Technology 1997年第5期13卷 389-396页

作者： Fu, S.Y. Lauke, B. institute for Polymer Research Dresden e.v 01069 Dresden Hohe Str.6 Germany

Acrylonitrile-butadiene-Styrene (ABS), with and without calcium carbonate (calcite) particles,was used as the matrix for reinforcement with as-rece.ved short-glass fibres (were originallytreated by the manufacturer) and sized short-glass fibres with two amino-silane coupling *** calcite particle content is 0, 11.7 and 23.5 vol. pct for the matrices. The glass fiber contentis 0, 10 and 15 vol. pct. The matrix materials and corresponding composites were compoundedusing a twin screw extruder and dumbbell-shaped tensile bars were prepared with an injectionmolding process. The tensile and flexural properties as well as the unnotched and notchedCharpy impact energies of short glass fibre/calcite/ABS composites were studied in this *** effects of fibres, fibre surface treatments and particles on these mechanical properties ofthe composites were discussed in detail. An importarit information was obtained, which is thatthe tensile and flexural strengths of hybrid SGF/calcite/ABS composites are the same as thoseof corresponding fibre composites when the ratio of the interfacial adhesion strength betweenparticles and matrix to that between fibres and matrix is higher than certain value. otherwise theformer are lower than the latter.

关键词： ABS Calcite/ABS Composites SGF Analysis of Mechanical Properties of Injection Molded Short Glass Fibre

Proteome Analyses of Hepatocellular Carcinoma

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Journal of Clinical and Translational Hepatology 2014年第1期2卷 23-30页

作者： Dominik A.Megger Wael Naboulsi Helmut e.Meyer Barbara Sitek Medizinisches Proteom-Center Ruhr-Universit(a)t Bochum Bochum Germany Medizinisches Proteom-Center Ruhr-Universit(a)t Bochum Bochum Germany leibniz-institut für analytische Wissenschaften isas-e.v. Dortmund Germany

Proteomics has evolved into a powerful and widely used bioanalytical technique in the study of cancer,especially hepatocellular carcinoma (HCC).In this review,we provide an up to date ove.view of feasible proteome-analytical techniques for clinical *** addition,we present a broad summaryof proteornic studies of HCC utilizing various technical approaches for the analysis of samples derived from diverse sources like HCC cell lines,animal models,human tissue and body fluids.

关键词： Proteomics Quantitative analysis Hepatocellular carcinoma Biomarker Cell lines Animal models Tissue samples

effect of excess Y_2O_3 addition on the physical properties of melt processed YBCO bulks

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Science China(Physics,Mechanics & Astronomy) 2004年第1期47卷 17-23页

作者： YANG Wanmin1,2,3, ZHOU Lian2, FeNG Yong2, ZHANG Pingxiang2, WU Minzhi3 & W. GAWALeK3 1. Department of Physics, Shaanxi Normal University, Xi抋n 710062, China 2. Northwest institute for Nonferrous Metal Research. Xi抋n 710016, China 3. institute fur Physikalische Hochtechnologie e.v(IPHT), Jena, Germany Correspondence should be addressed to Yang Wanmin (email: wm-yang@***) Rece.ved June 27, 2003 Department of Physics Shaanxi Normal University Xi’an China Northwest institute for Nonferrous Metal Research Xi’an China institute fur Physikalische Hochtechnologie e.v (IPHT) Jena Germany

The YBCO superconductors with Y2O3 addition were prepared by a modified melt textured process and the effects of excess Y2O3 addition on the physical properties of melt textured YBCO have been investigated. It is found that the melt temperature of YBCO samples decreases drastically with the increasing Y2O3, and the maximum levitation forces are drastically different for samples with different Y2O3 addition. It is also found that the optimal Y2O3 addition to YBCO is about 10wt%. Considering the microstructure and the starting composition, the results are well discussed and interpreted.

关键词： YBCO superconductor, melt growth, Y2O3 addition, levitation force.

Boosting propane dehydrogenation by gallium hydride species formed in situ

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Science China Chemistry 2024年第6期67卷 1753-1755页

作者： evgenii v.Kondratenko leibniz-institut für Katalyse e.v. Albert-Einstein-Str.29aRostock18059Germany

An inspiring paper recently published in Nature Chemistry[1]by the group of *** Gong at Tianjin University is the motivation for this highlight *** reported results show that the understanding of reaction-induced restructuring of heterogeneous catalysts is of great importance for their targeted development because usually unstable compounds can be formed and stabilized under reaction conditions.

关键词： conditions hydride stabilized

Probabilistic Analysis and Design of HCP Nanowires:An efficient Surrogate Based Molecular Dynamics Simulation Approach

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Journal of Materials Science & Technology 2016年第12期32卷 1345-1351页

作者： T.Mukhopadhyay A.Mahata S.Dey S.Adhikari College of engineering Swansea UniversitySwanseaUnited Kingdom Department of Materials Science and engineering Missouri University of Science and TechnologyRollaMOUSA Indian institute of Science BangaloreIndia leibniz-institut fur Polymerforschung Dresden e.v. DresdenGermany

We investigate the dependency of strain rate,temperature and size on yield strength of hexagonal close packed（HCP） nanowires based on large-scale molecular dynamics（MD） simulation.A variance-based analysis has been proposed to quantify relative sensitivity of the three controlling factors on the yield strength of the *** of the major drawbacks of conventional MD simulation based studies is that the simulations are computationally very intensive and economically *** scale molecular dynamics simulation needs supercomputing access and the larger the number of atoms,the longer it takes time and computational *** this reason it becomes practically impossible to perform a robust and comprehensive analysis that requires multiple simulations such as sensitivity analysis,uncertainty quantification and *** propose a novel surrogate based molecular dynamics（SBMD）simulation approach that enables us to carry out thousands of virtual simulations for different combinations of the controlling factors in a computationally efficient way by performing only few MD *** the SBMD simulation approach an efficient optimum design scheme has been developed to predict optimized size of the nanowire to maximize the yield *** the effect of inevitable uncertainty associated with the controlling factors has been quantified using Monte Carlo *** we have confined our analyses in this article for Magnesium nanowires only,the proposed approach can be extended to other materials for computationally intensive nano-scale investigation involving multiple factors of influence.

关键词： hcp-nanowire Yield strength Surrogate Monte Carlo simulation Uncertainty in nanoscale Sensitivity

Almost nonnegative curvature operator and cohomology rings

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Frontiers of Mathematics in China 2016年第5期11卷 1259-1274页

作者： Martin HeRRMANN Fakultat fur Mathematik Karlsruher Institut fur Technologie Kaiserstraβe 89-93 76133 Karlsruhe Germany

We give a survey of results on the construction of and obstructions to metrics of almost nonnegative curvature operator on closed manifolds and results on the cohomology rings of closed, simply-connected manifolds with a lower curvature and upper diameter bound. The latter is motivated by a question of Grove whether these condition imply finiteness of rational homotopy types. This question has answers by F. Fang-X. Rong, B. Totaro and recently A. Dessai and the present author.

关键词： Nonnegative curvature homogeneous spaces curvature operator almost nonnegative curvature

Palladium-catalyzed carbonylation of activated alkyl halides via radical intermediates

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Industrial Chemistry & Materials

Industrial Chemistry & Materials 2024年第2期2卷 276-283页

作者： Zhi-Peng Bao Xiao-Feng Wu Dalian National Laboratory for Clean energy Dalian Institute of Chemical PhysicsChinese Academy of Sciences116023 DalianLiaoningChina leibniz-institut für Katalyse e.v Albert-Einstein-Straße 29a18059 RostockGermany

Palladium-catalyzed carbonylation is an efficient approach to prepare carbonyl-containing compounds with high atomic economy in synthetic organic ***,in comparison with aryl halides,carbonylation of alkyl halides is relatively challenging due to the decreased stability of the palladium *** of activated alkyl halides is even more difficult,as nucleophilic substitution reactions with nucleophiles occur more easily with *** this article,we summarize and discuss recent achievements in palladium-catalyzed carbonylative reactions of activated alkyl *** transformations proceed through radical intermediates which are generated in various *** a relatively high pressure of carbon monoxide,the corresponding aliphatic carboxylic acid derivates were effectively prepared with various nucleophiles as the reaction *** alcohols,amines and organoboron reagents,four-component reactions in combination with alkenes or alkynes were also ***-by-case reaction mechanisms are discussed as well and a personal outlook has also been provided.

关键词： Carbonyl group Palladium catalysis Carbonylation Activated alkyl halides Radical intermediates

On the estimation of Solutions for Some Linear Systems of Differential equations

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Acta Mathematica Sinica,english Series 1998年第1期14卷 41-46页

作者： L. R. Awad e. M. el-Kholy Sh. el-Bendary Universitat Hamburg institut fur Angewandte Mathematik Bundesstraβe 55 20146 Hamburg Germany

In this paper we estimate the solutions of homogeneous linear system of differential equations with unbounded coefficients on the real line R. We also give a necessary and sufficient condition in order that the linear... 详细信息

关键词： Homogeneous linear Unbounded coefficient