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排序方式: 共有1193条查询结果,搜索用时 15 毫秒
971.
Masatomo Minagawa Takehiro Saito Yoshiaki Fujikura Toshiei Watanabe Hiroshi Iwabuchi Fumio Yoshii Takashi Sasaki 《应用聚合物科学杂志》1997,63(12):1625-1633
The mechanism by which surface modification of two kinds of synthetic rubbers (ethylene-propylene and chloroprene) was brought about by ultraviolet (UV) irradiation and sputter ion etching treatments was studied from a physicochemical point of view. The most remarkable effect of this irradiation treatment was the rapid increase in adhesion properties and the simultaneous decrease in self-stickiness. This nonsticking effect was particularly important for the rapid production of articles from thin rubber sheets. The surface modification mechanism was studied by use of SEM, ESCA, FTIR, and related interfacial analytical procedures. It was shown that surface roughening with a quite thin layer of surface oxidation (∼0.5 μm in depth) is a key factor for the development of nonsticking properties. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 63: 1625–1633, 1997 相似文献
972.
The so-called Clausius-Clapeyron equation, that is, the static equation of state for “solid-liquid-porous media” systems without liquid flow through the pores, has been experimentally examined by measuring the pore liqiud pressure at the solid-liquid interface in order to verify the accuracy of our method of measuring unfrozen pore liquid pressure. Several series of experiments have been carried out using water-saturated Ohya-Tuff as a porous medium specimen cooled from the top down. In these experiments, the solid-liquid interface was always fixed at the top surface of the specimen. The experimental results imply that the measurement method should be useful in determining the relative value of the unfrozen pore water pressure. © 1998 Scripta Technica, Inc. Heat Trans Jpn Res, 26(2): 69–83, 1997 相似文献
973.
The transmission properties of water and sodium chloride water solutions with various salt concentrations were investigated. This paper concerns the measurement of the spectral transmittance and the calculation of the total transmittance for water and NaCl water solutions. The spectral transmittance of the NaCl water solutions over the infrared and nearby regions increased with increasing salt concentration for constant specimen thickness and air mass. The spectral transmittance was found to be useful for precisely calculating the thermal performance of a solar pond, and by using an effective absorption coefficient, a five-partition method dividing the wavelengths into five bands by which the total transmittance up to a water depth of 3 m could be calculated, was found to be important as a practical method of solar pond technology. © 1997 Scripta Technica, Inc. Heat Trans Jpn Res, 26(1): 1–15, 1997 相似文献
974.
Kohei Ohta Nei Kato Glenn Mansfield Yoshiaki Nemoto 《International Journal of Network Management》1996,6(2):108-118
Configuring a network management system involves the delicate art of balancing the requirements of the management system with the available network resources. 相似文献
975.
Effect of metal oxide additives on the catalytic performance of Ga2O3–Al2O3 prepared by the sol–gel method for the selective reduction of NO with propene in the presence of oxygen was studied. Of several
metal oxide additives, the addition of In2O3 enhanced drastically the activity of Ga2O3–Al2O3 for NO reduction by propene in the presence of H2O. In addition, the activity of In2O3‐doped Ga2O3–Al2O3 catalyst was extremely intensified by the presence of H2O below 350°C. The promotional effect of H2O was interpreted by the suppression of undesirable propene oxidation and the removal of carbonaceous materials deposited
on the catalyst surface. We also found that close interaction of In2O3 and Ga2O3 is necessary for the enhancement of activity by H2O. A lot of hydrocarbons except methane and oxygenated compounds served as good reducing agents, among which propene and 2‐propanol
were the most efficient ones. In2O3‐doped Ga2O3–Al2O3 catalyst was capable of reducing NO into N2 quite efficiently in the presence of H2O at a very high space velocity.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
976.
977.
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979.
ABSTRACT Laser flash photolysis is a useful technique for disruption of photolabile chemical bonds. The kinetics of the subsequent reformation of such bonds can then be monitored with a suitable detection system. This technique has proven useful for following the reassociation kinetics of hemeproteins with carbon monoxide. We describe the construction of this apparatus using readily available components, along with microcomputer based signal acquisition and digital filtering of data using a fast Fourier transform. The application of this apparatus to measurement of the association of cytochrome P450 with carbon monoxide is described. 相似文献
980.
The adsorption of organic polar compounds onto iron sulfide and onto iron oxide was investigated using a flow microcalorimeter. The effects of a combination of an iron sulfide surface and surfactants on wear were examined in air and argon atmospheres using a ball-on-dish friction machine. The polar interaction and reactivity between organic polar compounds and iron sulfide are important functions for wear reduction. This was shown from the results obtained in the measurement of the heat of adsorption, amount of adsorption, heat of desorption and iron content in the desorption solution. The adsorption of stearic acid on the steel ball sulfidized in H2S reduced wear significantly in the air atmosphere. Surfactants contribute considerably to wear reduction when used with sulfur EP additives which form an iron sulfide film. 相似文献