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11.
Forster Jean L.; Jeffery Robert W.; Schmid Thomas L.; Kramer F. Matthew 《Canadian Metallurgical Quarterly》1988,7(6):515
Evaluated the feasibility and effectiveness of a program for weight gain prevention (WGP) in normal adults. 219 Ss were randomized to either WGP treatment or no treatment for 12 mo. The treatment group received monthly newsletters relating to weight management, participated in a financial incentive system, and were offered an optional 4-session education course in the 6th mo of the program. Results demonstrate high interest in WGP among Ss who were not objectively overweight. Participation, as measured by return of postcards sent with each newsletter, was approximately 75%. Results after 1 yr show a net weight loss of 1.8 lb in the group receiving the program compared with controls. 82% of participants maintained or lost weight, compared with 56% of controls. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
12.
Joseph L. Keddie Laura J. Norton Edward J. Kramer Emmanuel P. Giannelis 《Journal of the American Ceramic Society》1993,76(10):2534-2538
Neutron reflectometry (NR) was used to directly measure the interface width between a titanium dioxide and a silicon dioxide film deposited by sol-gel processing. In a bilayer heated to 450°C, NR measurements showed that the interface width is 0.8 nm. This width is the same as the roughness of a sol-gel silicon dioxide surface after the same heat treatment, suggesting no interdiffusion or mixing at the bilayer interface. 相似文献
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BACKGROUND AND PURPOSE: Norway has the highest reported incidence of hip fractures in western Europe. Little is known about the epidemiology of falls in Norway where the winter season is long and dark. The objective of this work was to study reported falls and their consequences among elderly Norwegians living at home. METHODS: A cross-sectional design was used for the study. Interviews were performed in the homes of 431 subjects, aged 67-97 years, living at home. Information on falling was gathered through six questions: whether the subject had fallen during the last six months, and if so, how many falls they had, where the last fall occurred, its perceived reason, the activity the subject had been engaged in when the fall occurred, and the resulting injury. RESULTS: In all, 24.1% of subjects reported falling during the last six months, and 9.5% had suffered more than one fall. Falls were most frequently linked to external events (63.1%). Outdoor falls were more frequent (59.0%; 95% CI = 51.2-82.0) than indoor falls. Older subjects were associated with more frequent indoor falls (p < 0.05), but gender was not significant. Fifty-one per cent of subjects had fallen while walking and 53% had suffered an injury from the last fall. In 13.4% of the women and 16.2% of the men, the last fall had resulted in a fracture. CONCLUSIONS: Compared to the results of other studies from industrialized Western countries, a similar crude fall rate, similar frequency and similar type of injury were found. However, in contrast to other studies, no gender difference was observed with regard to falling, place of falling and fracture rate. 相似文献
16.
Attentional control within 3-D space 总被引:1,自引:0,他引:1
Four experiments investigated whether directing attention to a particular plane in depth enables observers to filter out information from another depth plane. Observers viewed stereoscopic displays and searched for a red line segment among green line segments. The results showed that directing attention to a particular depth plane cannot prevent attentional capture from another depth plane when the colors of the target and distractor are identical. However, it can prevent attentional capture by a singleton from another depth plane when the colors of the target and distractor are different. These results indicate that only when both color and depth information are selective in guiding attention to the target singleton can attentional capture by irrelevant singletons be prevented. The results also suggest that retinal disparity does not have the same special status as location information in two dimensions and should be considered as just another feature along which selection may occur. 相似文献
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Dilute 3-component 1-phase solutions in methylene chloride of poly(styrene-acrylonitrile) PSAN and polycarbonate PC are used to cast phase separated thin films. Films of pure PSAN, pure PC and five intermediate compositions are examined. The films are bonded to copper grids and strained at a constant rate of 4.1 × 10–6sec–1. The median tensile strain
v for void formation is determined using an optical microscope and the regions surrounding the voids are examined by TEM. At room temperature and slow strain rates both PSAN and PC plastically deform by shear yielding. For pure PSAN
v was found to be 0.13 whereas for PC
v exceeds 0.23. The addition of the more ductile polymer PC to PSAN at weight fractionsx forx 0.4 decreases
v. In this case voids form in crazes at the boundaries between the PC-rich inclusion and the PSAN-rich matrix. When the PC content is increased tox = 0.8,
v approaches 0.23. The effect of physical ageing (annealing belowT
g the glass transition temperature) on the mode of plastic deformation was also examined over the same compositional range. Physical ageing was found to suppress shear deformation and favour crazing in PSAN and PSAN-rich phases. Because crazes are more susceptible to breakdown than DZ's (shear deformation zones), physical ageing results in a marked decrease in
v. The breakdown statistics of these phase separated partially compatible blends was found to follow a Weibull distribution in strain from which two parameters may be extracted: the Weibull modulus and
w the Weibull scale parameter. is a measure of the breadth of distribution of void initiation and
w is a measure of the median strain to void formation in the films. The behaviour of
w was found to approximately mirror
v. The Weibull modulus appears to be primarily controlled by the matrix phase. 相似文献
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The role of carbon produced from the decomposition of CO-CO2 gas mixtures traditionally is ignored during oxidation experiments, and only the oxygen potential established by the gas mixture is generally considered. Accordingly, to overcome this problem, a model which takes into account both carbon and oxygen dissolution into a p-type scale has been developed and tested. Two distinct cases of the model were tested at 1002°C. In the first case, variable CO/CO2 ratios were used to determine the parabolic kinetics. Thus, both variable oxygen and carbon potentials were studied. In the p-type region of MnO, the developed model appeared to hold quite well. In the second case, constant CO-CO2 ratios diluted with helium were utilized to maintain a constant oxygen potential with a variable carbon activity. The developed model appeared to hold again for the p-type region of MnO. Metallographically it was noted that the MnO scale developed exhibited an outer compact region and an inner layer that was somewhat porous. 相似文献
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