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核孔膜测定溶液浓度的原理、实验及应用前景

原子能科学技术 1992年第4期26卷 54-60页

作者：郭士伦王玉兰郝秀红樊中钧朱天成 H.A.Khan G.Hussain r.Brandt P.Vater 中国原子能科学研究院北京102413 PINSTECH.Islamabad Pakistan kernchemie universitat marburg f.r.germany

用实验证明,核孔膜可以用来测定溶液浓度,即测定溶液中溶质的含量。这一发展,为核孔膜在工业上广泛应用开辟了新的领域。本文对用核孔膜测定溶液浓度的原理、方法、精确度、适用范围和应用前景进行阐述。

关键词：核孔膜溶液浓度浓度测量

Enantioselective and Enantioconvergent Iron-Catalyzed C(sp^(3))-H Aminations to Chiral 2-Imidazolidinones

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Chinese Journal of Chemistry 2023年第17期41卷 2065-2070页

作者： Tianjiao Cui Chen-Xi Ye Jordan Thelemann Daniel Jenisch Eric Meggers fachbereich Chemie Philipps-Universitat MarburgHans-Meerwein-Strasse 435043MarburgGermany

Comprehensive Summary Enantioselective or enantioconvergent iron-catalyzed ring-closing C(sp^(3))-H aminations of N-aroyloxyurea through intermediate iron nitrene species provide chiral 2-imidazolidinones in up to 99%yield and with up to 95%ee(40 examples).This is a rare example in which sustainable iron catalysis is combined with C(sp^(3))-H amination and asymmetric catalysis.

关键词： Iron Asymmetric catalysis C-H activation Amination Nitrenes Heterocycles

Validation of Pore-Scale Simulations of Hydrodynamic Dispersion in random Sphere Packings

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Communications in Computational Physics 2013年第3期13卷 801-822页

作者： Siarhei Khirevich Alexandra Holtzel Ulrich Tallarek Department of Chemistry Philipps-Universitat MarburgHans-Meerwein-Strasse35032 MarburgGermany

We employ the lattice Boltzmann method and random walk particle tracking to simulate the time evolution of hydrodynamic dispersion in bulk,random,monodisperse,hard-sphere packings with bed porosities(interparticle void volume fractions)between the random-close and the random-loose packing *** JodreyTory and Monte Carlo-based algorithms and a systematic variation of the packing protocols we generate a portfolio of packings,whose microstructures differ in their degree of heterogeneity(DoH).Because the DoH quantifies the heterogeneity of the void space distribution in a packing,the asymptotic longitudinal dispersion coefficient calculated for the packings increases with the packings’*** investigate the influence of packing length(up to 150 d_(p),where d_(p) is the sphere diameter)and grid resolution(up to 90 nodes per d_(p))on the simulated hydrodynamic dispersion coefficient,and demonstrate that the chosen packing dimensions of 10 d_(p)×10 d_(p)×70 d_(p) and the employed grid resolution of 60 nodes per d_(p) are sufficient to observe asymptotic behavior of the dispersion coefficient and to minimize finite size *** values of the dispersion coefficients calculated for the generated packings are compared with simulated as well as experimental data from the literature and yield good to excellent agreement.

关键词： Packing microstructure degree of heterogeneity packing algorithm hydrodynamic dispersion random sphere packings

Poleward increase in feeding efficiency of leafminer Stigmella lapponica(Lepidoptera:Nepticulidae)in a latitudinal gradient crossing a boreal forest zone

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Insect Science 2023年第3期30卷 857-866页

作者： Mikhail V.Kozlov Vitali Zverev Tobias M.Sandner Erik J.van Nieukerken Elena L.Zvereva Department of Biology University of TurkuTurkuFinland Department of Biology Philipps-Universitat MarburgMarburgGermany Naturalis Biodiversity Center Leidenthe Netherlands

Damage to plant communities imposed by insect herbivores generally decreases from low to high *** decrease is routinely attributed to declines in herbivore abundance and/or diversity,whereas latitudinal changes in per capita food consumption remain virtually ***,we tested the hypothesis that the lifetime food consumption by a herbivore individual decreases from low to high latitudes due to a temperature-driven decrease in metabolic *** 2016 to 2019,we explored latitudinal changes in multiple characteristics of linear(gallery)mines made by larvae of the pygmy moth,Stigmella lapponica,in leaves of downy birch,Betula *** mined leaves were larger than intact leaves at the southern end of our latitudinal gradient(at 60°N)but smaller than intact leaves at its northern end(at 69°N),suggesting that female oviposition preference changes with *** latitudinal changes were observed in larval size,mine length or area,and in per capita food consumption,but the larval feeding efficiency(quantified as the ratio between larval size and mine size)increased with ***,*** larvae consumed less foliar biomass at higher latitudes than at lower latitudes to reach the same *** on space-for-time substitution,we suggest that climate warming will increase metabolic expenses of insect herbivores with uncertain consequences for plant-herbivore interactions.

关键词： Betula pubescens climate change food quality insect herbivory metabolic expenses oviposition preference

Artificial intelligence meets body sense: task-driven neural networks reveal computational principles of the proprioceptive pathway

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Signal Transduction and Targeted Therapy 2024年第8期9卷 3147-3149页

作者： Leonard E.van Dyck frank Bremmer Katharina Dobs Department of Psychology Justus Liebig University GiessenGiessenGermany Max Planck Institute for Human Cognitive and Brain Sciences LeipzigGermany Center for Mind Brain and BehaviorUniversities of MarburgGiessenand DarmstadtMarburgGermany Department of Neurophysics Philipps-Universitat MarburgMarburgGermany

In a recent study published in Cell,Marin Vargas and Bisi et al.1 present an innovative approach to unravel the computational principles underlying proprioceptive processing in non-human *** findings showcase the utility of task-driven modeling in advancing neuroscience and offer translational potential by providing seminal insights into the goals and mechanisms by which the brain encodes body position and movements.

关键词： networks neural principles

Homology of Powers of Ideals： Artin-rees Numbers of Syzygies and the Golod Property

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Algebra Colloquium 2016年第4期23卷 689-700页

作者： Jiirgen Herzog Volkmar Welker Siamak Yassemi fachbereich Mathematik Universitat Duisburg-Essen Campus Essen 45117 Essen Germany Philipps-universitat marburg Fachbereich Mathematik und Informatik 35032 Marburg Germany School of Mathematics Statistics and Computer Science College of Science University of Tehran Tehran Iran

Let ro be a Noetherian local ring and r a standard graded r0-algebra with maximal ideal ra and residue class field K = rim. for a graded ideal I in r we show that for k 〉〉 0：（1） the Artin-rees number of the syzygy modules of Ik as submodules of the free modules from a free resolution is constant, and thereby the Artin-rees number can be presented as a proper replacement of regularity in the local situation; and （2） r is a polynomial ring over the regular ro, the ring r/Ik is Golod, its Poincar4-Betti series is rational and the Betti numbers of the free resolution of K over r/I^k are polynomials in k of a specific degree. The first result is an extension of the work by Swanson on the regularity of I^k for k 〉〉 0 from the graded situation to the local situation. The polynomiality consequence of the second result is an analog of the work by Kodiyalam on the behaviour of Betti numbers of the minimal free resolution of r/Ik over r.

关键词： Artin-rees numbers syzygies Golod rings Betti numbers deviations

Towards an L^p Potential Theory for Sub-Markovian Semigroups:Kernels and Capacities

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Acta Mathematica Sinica,English Series 2006年第4期22卷 1227-1250页

作者： Niels JACOB renéL.SCHILLING Department of Mathematics University of Wales SwanseaSingleton ParkSwansea SA 2 8 PP.United Kinadom fB 12-Mathematik Philipps-Universitat MarburgD-35032 MarburgGermany

We study in fairly general measure spaces （X,μ） the （non-linear） potential theory of L^p sub-Markovian semigroups which are given by kernels having a density with respect to the underlying measure. In terms of mapping properties of the operators we provide sufficient conditions for the existence （and regularity） of such densities. We give various （dual） representations for several associated capacities and, in the corresponding abstract Bessel potential spaces, we study the role of the truncation property. Examples are discussed in the case of r^n where abstract Bessel potential spaces can be identified with concrete function spaces.

关键词： nonlinear potential theory (r,p)-capacity Bessel potential space gamma.transform sub-Markovian semigroup

Two Ways of High-Energy Heavy Ion Interactions: Spallation and Burst

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World Journal of Nuclear Science and Technology 2015年第2期5卷 73-87页

作者： reinhard Brandt Valery Ditlov Maria Haiduc Elena firu Alina Tania Neagu Eberhard Ganssauge reza Hashemi-Nezhad Wolfram Westmeier kernchemie FB Chemie Philipps-Universitat Marburg Marburg Germany Alikhanov Institute of Theoretical and Experimental Physics Moscow Russia Bucharest Institute of Space Sciences Bucharest Romania fachbereich Physik Philipps-Universitat Marburg Marburg Germany School of Physics University of Sydney Sydney Australia Dr. Westmeier GmbH Ebsdorfergrund Germany

A new approach to solving the observation of enhanced neutron production in high-energy heavy ion induced reactions in thick targets is presented. Two different reaction mechanisms in these interactions are considered: 1) Limited fragmentation of the projectile, called SPALLATION;2) Complete nuclear fragmentation of the projectile fragment into individual relativistic hadrons only, referred to as “BUrST”. The abundance of this second path increases with the charge and energy of the projectile and may be responsible for enhanced neutron production observed with radiochemical methods in 44 GeV 12C and 72 GeV 40Ar irradiations. Interactions of 72 GeV 22Ne in nuclear emulsions show that SPALLATION and BUrST have strongly different interaction signatures, and also that the rate of BUrSTS increases from (26 ± 3)% of all interactions in the 1st generation to (78 ± 6)% in the 2nd generation. further experimental signatures of BUrSTS will be described;however, no model based on physics concepts can be presented. This effect may have practical consequences for neutron safety considerations in the construction of advanced heavy ion accelerators.

关键词： Thick Target High Energy Projectile Unresolved Problems BUrST

Dependence of Gravity Induced Absorption Changes on the Earth’s Magnetic field as Measured during Parabolic flight Campaigns

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Journal of Modern Physics 2013年第11期4卷 1546-1553页

作者： Werner Schmidt fachbereich Biologie Philipps-Universitat MarburgMarburgGermany fachbereich Biologie Universitat KonstanzKonstanzGermany

Various spectroscopic experiments performed on the AIrBUS ZErO G—located in Bordeaux, france—in the years 2002 to 2012 exhibit minute optical reflection/absorption changes (GIACs) as a result of gravitational changes between 0 and 1.8 g in various biological species such as maize, oats, Arabidopsis and particularly Phycomyces sporangiophores. During a flight day, the AIrBUS ZErO G conducts 31 parabolas, each of which lasts about three minutes including a period of 22 s of weightlessness. So far, we participated in 11 parabolic flight campaigns including more than 1000 parabolas performing various kinds of experiments. During our campaigns, we observed an unexplainable variability of the measuring signals (GIACs). Using GPS-positioning systems and three dimensional magnetic field sensors, these finally were traced back to the changing earth’s magnetic field associated with the various flight directions. This is the first time that the interaction of gravity and the Earth’ magnetic field in the primary induction process in living system has been observed.

关键词： MDWS(Micro Dual Wavelength Spectrometer) GIAC(Gravity Induced Absorption Change) AIrBUS-300-ZErO-G Parabolic flight Micro-and Hypergravity Three Dimensional Earth’s Magnetic field Global Positioning System(GPS) Google Earth