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141.
Pretreatment of water samples using UV irradiation-peroxodisulfate for the determination of total mercury 总被引:1,自引:0,他引:1
Potassium peroxodisulfate (14 g l−1, 25 ml) has been observed to readily oxidize water under UV irradiation (30 W mercury arc tube), even at room temperature. The reaction is complete in 20 min, producing oxygen in stoichiometric amounts. The reaction was applied to pretreatment for the determination of total mercury by cold vapor atomic absorption spectrometry (AAS).The response of mercury(II) chloride by the UV irradiation method was higher than that by the standard permanganate method (95 °C, 2 h). The conversion efficiency of mercury by the UV irradiation method, the standard method and by non-treatment was found to be 100, 93.6 and 85.0%, respectively. The study is also applied to methylmercury, ethylmercury and phenylmercury chlorides. 相似文献
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Tadao Seguchi Takeshi Suwa Naoyuki Tamura Masaaki Takehisa 《Journal of Polymer Science.Polymer Physics》1974,12(12):2567-2576
The original morphology of polytetrafluoroethylene prepared by radiation-induced emulsion polymerization was studied by electron microscopy. The morphology depends on molecular weight, which in turn depends on polymerization conditions, especially the emulsifier concentration. The molecular weight decreases with increasing emulsifier concentration. The morphology changes with molecular weight roughly as follows: fibrils below 105, rods between 105 and 5 × 105, and granular particle above 106. The crystallinity is high for all morphologies. 相似文献
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The longitudinal relaxation time in the J = 2 ~ 1 rotational transition of OCS was measured by the method of two successive adiabatic rapid passages. The change in population of the J = 1 level due to the passage was observed as a change in absorption of the J = 1 ~ 0 transition. 相似文献
146.
Tadao Seguchi Naoyuki Tamura 《Journal of polymer science. Part A, Polymer chemistry》1974,12(8):1671-1682
The behavior of trapped radicals in polyethylene which is irradiated in air at room temperature, under grafting of methylmechacrylate or butadiene has been studied by electron spin resonance. Part of the alkyl radicals are converted to allyl radicals by reaction with double bonds and the others disappear by recombination under vacuum. The active species of grafting are alkyl radicals when the vapor pressure of monomers is relatively high, while at low pressure allyl radicals also play a role as well as alkyl radicals. In the grafting at 20°C, the grafting yields depend mainly on the decay rate of alkyl radicals which come out of the crystalline regions of polyethylene. The decay rate of alkyl radicals and the rate of grafting at the initial stage increase with decreasing crystallite size of polyethylene. 相似文献
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149.
We study the relation between the Kochen-Specker theorem (the KS theorem) and quantum computing. The KS theorem rules out a realistic theory of the KS type. We consider the realistic theory of the KS type that the results of measurements are either +1 or ?1. We discuss an inconsistency between the realistic theory of the KS type and the controllability of quantum computing. We have to give up the controllability if we accept the realistic theory of the KS type. We discuss an inconsistency between the realistic theory of the KS type and the observability of quantum computing. We discuss the inconsistency by using the double-slit experiment as the most basic experiment in quantum mechanics. This experiment can be for an easy detector to a Pauli observable. We cannot accept the realistic theory of the KS type to simulate the double-slit experiment in a significant specific case. The realistic theory of the KS type can not depicture quantum detector. In short, we have to give up both the observability and the controllability if we accept the realistic theory of the KS type. Therefore, the KS theorem is a precondition for quantum computing, i.e., the realistic theory of the KS type should be ruled out. 相似文献
150.
The reactions of benzonitrile in supercritical methanol, ethanol, and 2-propanol were investigated under non-catalytic conditions. In supercritical methanol, benzonitrile was converted to methyl benzoate in high yield. The esterification reaction also occurred in supercritical ethanol to afford ethyl benzoate in moderate yield. The esterification could occur via a route analogous to the Pinner reaction. On the other hand, benzonitrile in supercritical 2-propanol yielded no ester. Benzyl alcohol was the major product in supercritical 2-propanol. We investigated the reaction of the CN bond in supercritical 2-propanol. In supercritical 2-propanol, N-benzylideneaniline was transferred to the reduction product (N-benzylaniline) and hydrolysis products (benzyl alcohol and aniline). The hydrolysis reaction was restricted when the reaction was carried out in supercritical 2-propanol with a low water content. This indicates that the water in the 2-propanol acts as a reagent for the hydrolysis of the CN bond. These results suggested the following reaction process: C6H5CN→C6H5CHNH→C6H5CHO→C6H5CH2OH. 相似文献