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81.
82.
The rates of desorption of carbon dioxide from supersaturated water solutions into pure carbon dioxide or nitrogen gas stream were measured at 15,25, and 35°C in a baffled agitated vessel with a flat gas-liquid interface operated in a continuous manner. The volumetric liquid-phase mass transfer coefficients for the bubbles generated in the agitated liquid and the enhancement factors of the volumetric liquid-phase mass transfer coefficient for the free liquid surface due to the bubbling were calculated from the measured desorption rates and correlated as functions of the relative supersaturation of the solution and the liquid-phase Reynolds number. 相似文献
83.
Haruo Yoshimura Yoshihisa Endo Shigeru Hashimoto 《Journal of the American Oil Chemists' Society》1991,68(8):623-628
Terminal olefins can be converted into the corresponding sulfonates by sulfonation with SO3 followed by hydrolysis, the products are used as detergent ingredients. Although internal olefins were also expected to be
good feed stocks, it was difficult to convert them into the corresponding sulfonates with as good of a yield as that of terminal
olefins under the same synthesis conditions.
Our studies have been carried out in order to clarify the reason for poorer conversion of the internal olefins. It was found
by a nuclear magnetic resonance spectroscopic study that the major components of the sulfonated intermediate of internal olefins
wereβ-sultones, the amounts of which were usually very small in sulfonated terminal olefins. A portion of theseβ-sultones was desulfonated, depending on temperature, to the original olefins and the corresponding sulfate salts during alkaline
hydrolysis. The prevention of desulfonation of theβ-sultones in the hydrolysis process was one of the most important aspects for the production of internal olefin sulfonates.
Finally, by keeping the hydrolysis temperature below 35°C, the conversion of internal olefins into sulfonates was achieved
with the same yield as that of conventional terminal olefins. 相似文献
84.
Generally, plastics and plastic films are low in moisture absorption and high in electric insulation. They are inherently easy to be charged with static and can cause a variety of static troubles. We developed a functional packaging material to solve these static problems, by using potassium ionomer. We reported good antistatic performance (e.g. short static decay time, and excellent ash test) of potassium ionomer films in a previous paper. However, a mechanism underlying the antistatic property of potassium ionomer has not yet been fully elucidated. In this study, we measured the space charge distributions of potassium ionomer using the pulsed electro‐acoustic method. As a result of the space charge measurements, we found characteristic charge distribution of potassium ionomer film. On the basis of the existence of this characteristic charge distribution, we speculate that the space electric charge distribution of a potassium ionomer film under a direct current electric field shows apparent electric charge movement. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
85.
Yoshiharu Teragishi Toshio Takada Takamasa Nakajima Ryosuke Nogami 《Packaging Technology and Science》1993,6(4):221-233
A computer-controlled compression testing machine is used to compile a database of the static cushioning properties of package cushioning materials. Through research into automated data input procedures, so far not developed, a direct transfer program (ZABCON) has been devised, which allows direct access to the disk in which compression test data are stored. Elimination of manual data input has led to simplified and easy construction of a database, and the applied laboratory tests, such as that for determining the relationship between static cushioning properties and compression rate, can be performed quite readily. Also in this report, the application of the static cushioning characteristics of foamed polystyrene in the cushioning package design of dummy goods and the evaluation of its reliability by drop testing are discussed. 相似文献
86.
Shigeki Shibayama Takeo Kakuta Nobuyoshi Miyazaki Haruo Yokota Kunio Murakami 《New Generation Computing》1984,2(2):131-155
This paper describes the basic concepts, design and implementation decisions, standpoints and significance of the database machine Delta in the scope of Japan’s Fifth Generation Computer Project. Delta is planned to be operational in 1985 for researchers’ use as a backend database machine for logic programming software development. Delta is basically a relational database machine system. It combines hardware facilities for efficient relational database operations, which are typically represented by relational algebra, and software which deals with hardware control and actual database management requirements. Notable features include attribute-based internal schema in accordance with the characteristics found in the relation access from logic programming environment. This is also useful for the hardware relational algebra manipulation algorithm based on merge-sorting of attributes by hardware and a large capacity Semiconductor Disk for fast access to databases. Various implementation decisions of database management requirements are made in this novel system configuration, which will be meaningful to give an example for constructing a hardware and software combination of a relational database machine. Delta is in the stage between detailed design and implementation. 相似文献
87.
Takeki Nogami Yoshihide Yokoi Hideo Ichiba Yoshihiro Atsumi 《Electrical Engineering in Japan》1995,115(1):93-103
This paper describes a method available for early detection of abnormality in an oil-filled transformer. In this method, four gas sensors having different characteristics and neural network are used to identify gas species (H2, CH4, C2H4, C2H2 and mixture of two species). To improve the selectivity of gas sensors, the time response patterns induced by changing sensor temperature and the stationary sensor output are identified by neural network. Furthermore, the mixture ratio of gases is derived by using the stationary sensor output in response to the changing sensor temperature. Gas species are well discriminated, and the mixture ratio derived from the sensor output agrees well with the measurement by gas chromatography. Therefore, it is confirmed that our method is applicable to the transformer diagnostic technology. 相似文献
88.
Raman Spectroscopic Studies on the Formation Mechanism of Hydrous-Zirconia Fine Particles 总被引:1,自引:0,他引:1
Koji Matsui Hajime Suzuki Michiharu Ohgai Haruo Arashi 《Journal of the American Ceramic Society》1995,78(1):146-152
The Raman spectra of hydrous-zirconia fine particles produced by the hydrolysis of various ZrOCl2 solutions were investigated. The Raman spectra of hydrous zirconia synthesized at HCl concentrations below 1 mol/L were similar to those of monoclinic, crystalline ZrO2 ; those of hydrous zirconia synthesized at HCl concentrations greater than 1 mol/L showed a crystal structure change. The line width of the Raman bands increased with increasing H+ ion concentration. Analyzing the relationship between Raman band width and particle size revealed that the primary particle size of hydrous zirconia was controlled by the H+ and Cl− ions, because these ions interfered with the polymerization in a hydrolysis reaction. Based on the experimental results, the formation mechanism for primary particles of hydrous zirconia was determined. 相似文献
89.
90.