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The evolution of a homogeneous multicomponent cosmological model with interacting spinor, vector, and scalar fields in the
presence of dark energy described by the ideal liquid with the corresponding state equation is considered. The source of the
vector and spinor fields is the kinetic energy of the inflation (scalar) field that is modeled by introduction of Lagrangians
for the spinor and vector fields interacting with the scalar field through the squared gradient. A system of the dynamic Einstein–Proca–Klein–Fock
and ideal liquid equations in the presence of interaction of the cosmological model components is solved. The role of individual
components in the process of model evolution is elucidated. 相似文献
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V. A. Pal’chikov S. Yu. Mykolenko A. N. Pugach F. I. Zubkov 《Russian Journal of Organic Chemistry》2017,53(5):656-662
Composition of aminolysis products of phenyl glycidyl ether with benzylamine in various conditions was studied. The ratio of 1-(benzylamino)-3-phenoxypropan-2-ol and 1,1'-(benzylazanediyl)bis(3-phenoxypropan-2-ol) does not considerably depend on the nature of the solvent and is basically determined by ratio of initial reagents. 2,6-Bis(phenoxymethyl)morpholine was obtained by dehydration of aminodiol in conditions of Mitsunobu reaction with subsequent reductive debenzylation. 相似文献
6.
L.A. Fil’shtinskii Yu.D. Kovalev E.S. Ventsel 《International Journal of Solids and Structures》2010,47(11-12):1490-1495
In this paper, a symmetric boundary value problem of the stress analysis for an equilibrium of layer with end-supports covered by diaphragms and weakened by several loaded stress raisers is investigated. The given boundary value problem is reduced to an infinite system of singular integral equations of the second kind. The expressions for stress components in an elastic layer weakened by stress raisers are presented. Based on the developed analytical procedure, extensive numerical investigations have been conducted. The results of these investigations are illustrated graphically exposing some novel qualitative and quantitative knowledge about stress concentration in the layer depending on some geometric parameters of stress raisers and Poisson’s ratio of a layer material. 相似文献
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V. A. Pal’chikov I. S. Zarovnaya P. G. Dul’nev 《Russian Journal of Organic Chemistry》2018,54(7):1061-1070
While developing methods of synthesis of sulfolanes fused through the C3–C4 bond to oxazolidin-2- one and morpholin-2-one fragments, the reactivity of cis- and trans-isomeric amino alcohols of the sulfolane series toward a number of cyclizing agents was studied. The cis isomers reacted with dimethyl acetylenedicarboxylate and triphosgene to afford the corresponding morpholin-2-ones and oxazolidin-2-ones, whereas the trans isomers gave rise to open-chain aminofumarates and urea derivatives, respectively. The reactions of both cis- and trans-amino alcohols with oxalic acid derivatives (diethyl oxalate, oxalyl chloride) led to the formation of exclusively acyclic mono- and/or diamides. 相似文献
8.
Yu. A. Kucheryaev V. G. Pal’chikov Yu. A. Pchelin Yu. L. Sokolov V. P. Yakovlev 《JETP Letters》2005,81(12):644-646
The interference of the 2P state of the hydrogen atom due to unknown long-range interaction with the metal surface (Sokolov effect) has been studied by an atomic interferometer. In contrast to previous experiments, where an atomic beam passed through slits in metal plates, a beam in the presented experiments passes at a given distance from the edges of the plates. It has been found that the interference is clearly observed if two plates are located on the same side of the beam. However, this interference disappears if one plate is displaced to the opposite side. This result cannot be explained in the framework of the available hypotheses on the nature of the effect under investigation. 相似文献
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The review analyzes methods for the synthesis of amino alcohols containing cage-like norbornene, norbornane, and adamantane fragments. Such reactions of amino alcohols as selective functionalization of hydroxy and amino groups, as well as heterocyclizations with formation of nitrogen- and oxygen-containing heterocycles, are considered. Biological activity of cage-like amino alcohols and their derivatives and their use as ligands in catalytic asymmetric syntheses are discussed. 相似文献
10.
Gabelica V Vreuls C Filée P Duval V Joris B Pauw ED 《Rapid communications in mass spectrometry : RCM》2002,16(18):1723-1728
The noncovalent complexes between the BlaI protein dimer (wild-type and GM2 mutant) and its double-stranded DNA operator were studied by nanospray mass spectrometry and tandem mass spectrometry (MS/MS). Reproducibility problems in the nanospray single-stage mass spectra are emphasized. The relative intensities depend greatly on the shape of the capillary tip and on the capillary-cone distance. This results in difficulties in assessing the relative stabilities of the complexes simply from MS(1) spectra of protein-DNA mixtures. Competition experiments using MS/MS are a better approach to determine relative binding affinities. A competition between histidine-tagged BlaIWT (BlaIWTHis) and the GM2 mutant revealed that the two proteins have similar affinities for the DNA operator, and that they co-dimerize to form heterocomplexes. The low sample consumption of nanospray allows MS/MS spectra to be recorded at different collision energies for different charge states with 1 microL of sample. The MS/MS experiments on the dimers reveal that the GM2 dimer is more kinetically stable in the gas phase than the wild-type dimer. The MS/MS experiments on the complexes shows that the two proteins require the same collision energy to dissociate from the complex. This indicates that the rate-limiting step in the monomer loss from the protein-DNA complex arises from the breaking of the protein-DNA interface rather than the protein-protein interface. The dissociation of the protein-DNA complex proceeds by the loss of a highly charged monomer (carrying about two-thirds of the total charge and one-third of the total mass). MS/MS experiments on a heterocomplex also show that the two proteins BlaIWTHis and BlaIGM2 have slightly different charge distributions in the fragments. This emphasizes the need for better understanding the dissociation mechanisms of biomolecular complexes. 相似文献