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101.
The present paper aims at deriving a systematic expression of the second order reduced density matrixΩ 2 in the case of a condensed system of identical spinless bosons. The derivation lends itself to generalization leading to higher order reduced density matricesΩ n ,n>2, that are consistent with the hierarchical set of equations of motion for the differentΩ n . 相似文献
102.
Pyrolysis-gas chromatography-mass spectrometry has been applied to the study of N-acetyl-d-glucosamine, chitin and chitosans of varying degrees of deacetylation prepared from chitin. An examination of the pyrograms of samples of chitosan revealed that there is a direct correlation between the amine content and the ratio of the areas of the peaks derived from the glucosamine and N-acety-d-glucosamine moieties. 相似文献
103.
104.
105.
The completeness of precipitation of anions and basic radicals by the two group reagents, zinc acetate and cadmium nitrate, has been investigated. It has been shown that the two reagents precipitate many of the anions quantitatively and can thus be used for their gravimetric estimation. 相似文献
106.
N. Bhandari J. N. Goswami D. Lal D. Macdougall A. S. Tamhane 《Proceedings Mathematical Sciences》1972,76(1):27-50
An experimental technique has been developed for systematic measurements of fossil tracks along selected planes cut from grains and rocks. With controlled etching, the technique allows successive revelation of tracks in different minerals in the same section, a typical sequence being olivine, anorthite, clinopyroxene. It thus becomes possible to study precisely the cosmic ray track density variations over dimensions much greater than those of individual crystals. The technique also provides accurate information on the relative recording characteristics of different minerals present in a rock and cosmic ray tracks can be studied with a minimum interference of tracks due to spontaneous fission of uranium and transuranic elements. Continuous chains of sections, each section measuring approximately 1 cm., have been cut along several different planes in fifteen rocks from Mare Tranquillitatis, Oceanus Procellarum and Fra Mauro region. The cosmic ray track measurements from these sections have provided dramatic evidence for a number of processes affecting lunar rocks. The statistical, and non-uniform nature of erosion by micrometeorite bombardment can be seen in sections intersecting exposed surface which show regions of very steep track density gradients interspersed with eroded regions having lower track densities. The thick section technique permits determination of the energy spectrum of VH nuclei from track density gradients that extend over distances limited only by the dimensions of the rock, and, more important, in samples of identical orientation. The latter is particularly important in higher energy regions (deeper within the rock) where variations in crystal orientation cause track density differences of the same order as real changes in the gradient. Also in the near surface regions of rocks where low energy particles produce steep track density gradient, the thick section method has proved indispensable since it permits accurate depth determinations not possible in the spot sampling procedure. In this paper the technique of studying track profiles in thick sections is described. Although developed primarily for studying lunar samples, the thick section technique is also useful for similar studies in meteorites, particularly for gas-rich meteorites containing irradiated grains. In contrast to single grain studies, thick sections preserve the grain boundaries and permit accurate depth—density measurements. In addition thick section studies have revealed occasional large uniformly irradiated lithic fragments which would not have been possible to discover by spot sampling methods. 相似文献
107.
108.
A nuclear matter test has been conducted on a separable non-localN-N interaction proposed by Sirohi and Srivastava. The potential had been constructed by fitting the phase-shifts. The results
obtained compare with those obtained by Tabakin in each partial wave. The binding energy per particle and the symmetry energy
coefficient obtained are 19.4 MeV and 66.5 MeV respectively atk
F=1.65 fm−1, while the best estimated values for these quantities are 16 MeV and 30–35 MeV atk
F=1.5 fm−1. Single particle potential generated out of this NLSI has in general the same shape as the one obtained through Tabakin potential.
Finally as a test of non-locality the integrated photoabsorption cross-section parameterh has been calculated and the value of 1.03 agrees with other reported values. 相似文献
109.
Hornblende which occurs in igneous and metamorphic rocks is well suited for age determination by the fission track method. The tracks which are readily etched in hydrofluoric acid are annealed in 1 hr at 530° C. Extrapolation of the experimentally determined temperatures suggest that a temperature of 200° C for one m.y. will erase all the tracks present before the heating. Fission track ages of hornblende agree with the main orogenic metamorphic cycles. 相似文献
110.
Pramana - The absorption and fluorescence spectra of Ho3+:LaF3, in the wavelength region from 4000 Å to 7500 Å have been reinvestigated incorporating polarization features, for the first... 相似文献