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71.
Curtis L Cooper Navneet K Ahluwalia Susan M Efler Jörg Vollmer Arthur M Krieg Heather L Davis 《Journal of immune based therapies and vaccines》2008,6(1):3
Background
Chronic hepatitis C virus (HCV) infection results from weak or absent T cell responses. Pegylated-interferon-alpha (IFN-α) and ribavirin, the standard of care for chronic HCV, have numerous immune effects but are not potent T cell activators. A potent immune activator such as TLR9 agonist CpG oligodeoxynucleotide (CpG) may complement current treatment approaches. 相似文献72.
Aloys Krieg 《Linear and Multilinear Algebra》1987,21(4):325-344
There exists a diagonal form with certain divisibility conditions for matrices over the Hurwitz order of integral quaternions under unimodular equivalence. The diagonal entries are uniquely determined up to similarity. Given two such diagonal forms, where the diagonal entries are similar by pairs, the matrices prove to be ummodularly equivalent, whenever the rank of the matrices is creater than one. 相似文献
73.
74.
R. Krieg 《Applied Mathematical Modelling》1978,2(2):81-89
Some important problems in coupled fluid-structural dynamics which occur in safety investigations of liquid metal fast breeder reactors (LMFBR), light water reactors and nuclear reprocessing plants are discussed and a classification of solution methods is introduced. A distinction is made between the step by step solution procedure, where available computer codes in fluid and structural dynamics are coupled, and advanced simultaneous solution methods, where the coupling is carried out at the level of the fundamental equations. Results presented include the transient deformation of a two-row pin bundle surrounded by an infinite fluid field, vapour explosions in a fluid container and containment distortions due to bubble collapse in the pressure suppression system of a boiling water reactor. A recently developed simultaneous solution method is presented in detail. Here the fluid dynamics (inviscid, incompressible fluid) is described by a singularity method which reduces the three-dimensional fluid dynamics problem to a two-dimensional formulation. In this way the three-dimensional fluid dynamics as well as the structural (shell) dynamics can be described essentially by common unknowns at the fluid-structural interface. The resulting equations for the coupled fluid-structural dynamics are analogous to the equations of motion of the structural dynamics alone. 相似文献
75.
Dr. Katharina Bleher Prof. Dr. Peter Comba Dr. Dieter Faltermeier Dr. Ashutosh Gupta Dr. Marion Kerscher Dr. Saskia Krieg Dr. Bodo Martin Dr. Gunasekaran Velmurugan Shuyi Yang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(4):e202103452
Oxidation of the iron(II) precursor [(L1)FeIICl2], where L1 is a tetradentate bispidine, with soluble iodosylbenzene (sPhIO) leads to the extremely reactive ferryl oxidant [(L1)(Cl)FeIV=O]+ with a cis disposition of the chlorido and oxido coligands, as observed in non-heme halogenase enzymes. Experimental data indicate that, with cyclohexane as substrate, there is selective formation of chlorocyclohexane, the halogenation being initiated by C−H abstraction and the result of a rebound of the ensuing radical to an iron-bound Cl−. The time-resolved formation of the halogenation product indicates that this primarily results from sPhIO oxidation of an initially formed oxido-bridged diiron(III) resting state. The high yield of up to >70 % (stoichiometric reaction) as well as the differing reactivities of free Fe2+ and Fe3+ in comparison with [(L1)FeIICl2] indicate a high complex stability of the bispidine-iron complexes. DFT analysis shows that, due to a large driving force and small triplet-quintet gap, [(L1)(Cl)FeIV=O]+ is the most reactive small-molecule halogenase model, that the FeIII/radical rebound intermediate has a relatively long lifetime (as supported by experimentally observed cage escape), and that this intermediate has, as observed experimentally, a lower energy barrier to the halogenation than the hydroxylation product; this is shown to primarily be due to steric effects. 相似文献
76.
Mahmud Abu-Odeh Dr. Katharina Bleher Neethinathan Johnee Britto Prof. Dr. Peter Comba Dr. Michael Gast Prof. Madhavan Jaccob Dr. Marion Kerscher Dr. Saskia Krieg Marius Kurth 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(44):11377-11390
The nonheme iron(IV)-oxido complex trans-N3-[(L1)FeIV=O(Cl)]+, where L1 is a derivative of the tetradentate bispidine 2,4-di(pyridine-2-yl)-3,7-diazabicyclo[3.3.1]nonane-1-one, is known to have an S=1 electronic ground state and to be an extremely reactive oxidant for oxygen atom transfer (OAT) and hydrogen atom abstraction (HAA) processes. Here we show that, in spite of this ferryl oxidant having the “wrong” spin ground state, it is the most reactive nonheme iron model system known so far and of a similar order of reactivity as nonheme iron enzymes (C−H abstraction of cyclohexane, −90 °C (propionitrile), t1/2=3.5 sec). Discussed are spectroscopic and kinetic data, supported by a DFT-based theoretical analysis, which indicate that substrate oxidation is significantly faster than self-decay processes due to an intramolecular demethylation pathway and formation of an oxido-bridged diiron(III) intermediate. It is also shown that the iron(III)-chlorido-hydroxido/cyclohexyl radical intermediate, resulting from C−H abstraction, selectively produces chlorocyclohexane in a rebound process. However, the life-time of the intermediate is so long that other reaction channels (known as cage escape) become important, and much of the C−H abstraction therefore is unproductive. In bulk reactions at ambient temperature and at longer time scales, there is formation of significant amounts of oxidation product – selectively of chlorocyclohexane – and it is shown that this originates from oxidation of the oxido-bridged diiron(III) resting state. 相似文献
77.
Dr. Matthias Krieg Florian Reicherter Dr. Peter Haiss Dr. Markus Ströbele Dr. Klaus Eichele Michael‐John Treanor Prof. Dr. Renald Schaub Prof. Dr. Holger F. Bettinger 《Angewandte Chemie (International ed. in English)》2015,54(28):8284-8286
The synthesis of a hexa‐peri‐hexabenzocoronene (HBC) with a central borazine core is described. The solid‐state structure of this BN‐doped HBC (BN‐HBC) is isotypic with that of the parent HBC. Scanning tunneling microscopy shows that BN‐HBC lies flat on Au(111) in a two‐dimensional pattern. 相似文献
78.
Wolfgang Jeitschko Aloys J. Foecker Dirk Paschke Martin V. Dewalsky Ch. B. H. Evers Bernd Künnen Arne Lang Gunter Kotzyba Ute Ch. Rodewald Manfred H. Mller 《无机化学与普通化学杂志》2000,626(5):1112-1120
The new cubic compound Fe0.5Ni0.5P3 (a = 775.29(5) pm) as well as the known compounds CoP3 and NiP3 were synthesized from the elemental components using tin as a flux. Their skutterudite (CoAs3) type structures were refined from single‐crystal X‐ray data. The new compound GdFe4P12 was prepared by reaction of an alloy Gd1/3Fe2/3 with phosphorus in a tin flux. Its cubic “filled” skutterudite (LaFe4P12 type) structure was refined from single‐crystal X‐ray data: a = 779.49(4) pm, R = 0.019 for 304 structure factors and 11 variable parameters. SmFe4P12 shows Van Vleck paramagnetism while GdFe4P12 is a soft ferromagnet with a Curie temperature of TC = 22(5) K. Both are metallic conductors. The new isotypic polyarsenide NdFe4As12 (a = 830.9(1) pm) was obtained by reacting NdAs2 with iron and arsenic in the presence of a NaCl/KCl flux. The new isotypic polyantimonide Eu0.54(1)Co4Sb12 (a = 909.41(8) pm) was prepared by reaction of EuSb2 with cobalt and antimony. Its structure was refined from single‐crystal X‐ray data to a residual of 0.024 (137 F values, 12 variables). A comparison of the Fe–P and P–P bond lengths in the compounds AFe4P12, where the A atoms (A = Ce, Eu, Gd, Th) have differing valencies, suggests that the Fermi level cuts through Fe–P bonding and P–P antibonding bands. 相似文献
79.
80.
Szabolcs Borsányi Ydalia Delgado Stephan Dürr Zoltán Fodor Sándor D. Katz Stefan Krieg Thomas Lippert Dániel Nógrádi Kálmán K. Szabó 《Physics letters. [Part B]》2012
We study QCD thermodynamics using two flavors of dynamical overlap fermions with quark masses corresponding to a pion mass of 350 MeV. We determine several observables on Nt=6 and 8 lattices. All our runs are performed with fixed global topology. Our results are compared with staggered ones and a nice agreement is found. 相似文献