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71.
E. I. Rau S. A. Ditsman S. V. Zaitsev N. V. Lermontov A. E. Luk’yanov S. Yu. Kupreenko 《Bulletin of the Russian Academy of Sciences: Physics》2013,77(8):951-958
Semiempirical relations for the following basic parameters of backscattered electrons in a scanning electron microscope are derived: reflection coefficient; average and most probable energies; energy spectra; and energy of backscattered electrons, depending on the angle of exit. The energy dependence is shown to have a maximum in the angular region of backscattered electrons Θ = 65°–75°. 相似文献
72.
R. Kalinowski L.T. Baczewski J. Raułuszkiewicz D. Givord A. Liénard C. Meyer 《Czechoslovak Journal of Physics》1997,47(4):415-419
Cr/Tb/Cr thin films have been obtained by pulsed laser deposition (PLD) on sapphire
substrates. The crystal structure of the films was characterised in-situ by means of reflection high energy electron diffraction (RHEED) and Auger spectroscopy (AS) and ex-situ by X-ray grazing incidence diffraction (GID) and scanning tunnelling microscopy (STM). The deposition of chromium on the Tb(0001) layers at 300 °C was found to lead to the formation of three Cr(110) crystalline domains. Chromium deposited on Tb(0001) initially (first 50 Å) at room temperature and then at 300 °C grew epitaxially in the [111] direction and formed two Cr(111) crystalline domains shifted by 30°. Due to the lower density of the atoms in Cr(111) plane, compared to the Cr(110) and Cr(001) ones, this orientation is interesting for magnetic studies. 相似文献
73.
Miroslav S. Leskiv Julietta V. Rau Daniela Ferro Felix M. Spiridonov 《Journal of fluorine chemistry》2008,129(6):529-534
The thermal decomposition of cobalt trifluoride was studied by High Temperature Mass Spectrometry (HTMS). It was ascertained that the rate of atomic fluorine evolution in the gas phase might be increased by adding small amounts of Ni(s) or CoF2(s) to cobalt trifluoride. Scanning Electron Microscopy combined with Energy Dispersive X-ray spectroscopy (SEM/EDX) was used to determine the morphology and composition of the solid product surface layer formed under different rates of CoF3(s) thermolysis. 相似文献
74.
Gottschaldt M Koth D Müller D Klette I Rau S Görls H Schäfer B Baum RP Yano S 《Chemistry (Weinheim an der Bergstrasse, Germany)》2007,13(36):10273-10280
Novel ligands have been obtained from the reaction of 4,4'-dibromomethyl-2,2'-bipyridine with 2,3,4,6-tetra-O-acetyl-beta-D-glucopyranosylthiol, 2,3,4,6-tetra-O-acetyl-beta-D-galactopyranosylthiol or 2,3,4,6-tetra-O-acetyl-alpha-D-thioacetylmannopyranoside in which the sugar residues are thioglycosidically linked to the bipyridine in the 4,4'-position. Cleavage of the acetyl groups affords hydrophilic symmetric ligands with free hydroxyl groups. Reaction of the new glycoconjugated ligands (L) with [Re(CO)(5)Cl] yields fluorescent complexes of general formula [Re(L)(CO)(3)Cl], which were characterised by mass spectrometry, elemental analysis and (1)H and (13)C NMR, IR, UV/Vis and fluorescence spectroscopy. These complexes exhibit excellent solubility and stability in organic solvents or water, depending on the residues of the sugar. One complex, namely tricarbonyl-4,4'-bis[(2,3,4,6-tetra-O-acetyl-beta-D-glycopyranosyl)thiomethyl]-2,2'-bipyridinerheniumtricarbonylo chloride, has been characterised by X-ray crystallography. A non-symmetric structure of the complexes could be assigned. Radiolabelling of the unprotected ligands with [(99m)Tc(H(2)O)(3)(CO)(3)](+) affords the corresponding water-soluble technetium complexes (in quantitative yields), which were characterised by their HPLC radiation traces. The formed complexes are stable for several hours in the presence of histidine but show partial ligand-exchange after one day. 相似文献
75.
Anthraquinone and viologen moieties were combined to dyadic molecules with two redox centers. These dyades and their constituents were used as acceptors in photo‐induced electron‐transfer reactions. The experiments show that a caveat is necessary if one tries to derive the properties and the reactions of the dyades from those of their constituents: the spectral properties appear to be independent superpositions of those of the constituents. However, the redox potentials of the two redox centres in the dyades deviate from that of their constituents, the methylene bridge can not suppress a considerable interaction between the two redox centres. This is especially true when the redox potentials of the constituents are close to one another. From the quenching experiments, it can be concluded that electrolyte cations like Na+ are engaged in the transition states of the electron‐transfer reactions. In this way, they can control the fate of the transferred electron. 相似文献
76.
77.
78.
Jochen Rau 《Annals of Physics》2009,324(12):2622-2637
Quantum theory shares with classical probability theory many important properties. I show that this common core regards at least the following six areas, and I provide details on each of these: the logic of propositions, symmetry, probabilities, composition of systems, state preparation and reductionism. The essential distinction between classical and quantum theory, on the other hand, is shown to be joint decidability versus smoothness; for the latter in particular I supply ample explanation and motivation. Finally, I argue that beyond quantum theory there are no other generalisations of classical probability theory that are relevant to physics. 相似文献
79.
Rau María S. Gennero de Chialvo María Rosa Chialvo Abel C. 《Journal of Solid State Electrochemistry》2012,16(5):1893-1900
The carbon monoxide oxidation reaction (COOR) was studied on steady-state conditions by chronoamperometry on polycrystalline
smooth platinum and ruthenium rotating disc electrodes in CO-saturated acid solution. The chronoamperometric response did
not show current oscillations and therefore the current density (j) vs. overpotential (η) curves on steady state could be obtained. In order to interpret these results, kinetic expressions were derived starting
from the mechanism proposed by S. Gilman, which considers two adsorbed reaction intermediates, carbon monoxide (COad) and hydroxyl (OHad). Analytical expressions as a function of overpotential for the current density, the surface coverage of the adsorbed species
(θ
CO and θ
OH) and the CO and CO2 pressures at the electrode surface on steady state were obtained. This set of equations was used for the correlation of the
experimental polarization curves and the evaluation of the corresponding kinetic parameters. From these values, the dependences
of the surface coverage of the adsorbed intermediates on overpotential were simulated, as well as those of the partial pressure
of CO and CO2. Thus, it was demonstrated that the Gilman’s mechanism accurately describes the experimental results on steady state of the
COOR on these metals. 相似文献
80.
Jochen Rau 《Physics letters. A》2012,376(4):370-373
In quantum state tomography, one potential source of error is uncontrolled contact of the system with a heat bath whose detailed properties are not known, and whose impact on the system moreover varies between different runs of the experiment. Precisely these variations provide a handle for reconstructing the system?s effective relaxation dynamics. I propose a pertinent estimation scheme which is based on a steepest-descent ansatz and maximum likelihood. After reconstructing the relaxation dynamics, the original quantum state of the system can be constrained to a curve in state space. 相似文献