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81.
There is a long history of attempts to explain why music is perceived as expressing emotion. The relationship between pitches serves as an important cue for conveying emotion in music. The musical interval referred to as the minor third is generally thought to convey sadness. We reveal that the minor third also occurs in the pitch contour of speech conveying sadness. Bisyllabic speech samples conveying four emotions were recorded by 9 actresses. Acoustic analyses revealed that the relationship between the 2 salient pitches of the sad speech samples tended to approximate a minor third. Participants rated the speech samples for perceived emotion, and the use of numerous acoustic parameters as cues for emotional identification was modeled using regression analysis. The minor third was the most reliable cue for identifying sadness. Additional participants rated musical intervals for emotion, and their ratings verified the historical association between the musical minor third and sadness. These findings support the theory that human vocal expressions and music share an acoustic code for communicating sadness. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
82.
Electrochemical superabrasive machining of a nickel-based aeroengine alloy using mounted grinding points 总被引:3,自引:0,他引:3
Brief design and manufacture considerations are detailed for a hybrid electrochemical grinding unit adapted from a vertical machining centre using a 40,000 rpm spindle and 500 A DC generator. Subsequently, experimental work is presented on the influence of tool bond systems, superabrasive grit type and electrical parameters when simultaneous ECM/grinding Udimet 720 using 10-15 mm diameter plain points. Single layer electroplated CBN tools produced G-ratios and maximum normal cutting forces of ∼451 and ∼45 N, respectively, compared to ∼128 and 557 N for equivalent diamond wheels. Data on workpiece roughness and overcut are also presented as are initial results for a fir tree shaped tool. 相似文献
83.
Although most research on the control of automatic prejudice has focused on the efficacy of deliberate attempts to suppress or correct for stereotyping, the reported experiments tested the hypothesis that automatic racial prejudice is subject to common social influence. In experiments involving actual interethnic contact, both tacit and expressed social influence reduced the expression of automatic prejudice, as assessed by two different measures of automatic attitudes. Moreover, the automatic social tuning effect depended on participant ethnicity. European Americans (but not Asian Americans) exhibited less automatic prejudice in the presence of a Black experimenter than a White experimenter (Experiments 2 and 4), although both groups exhibited reduced automatic prejudice when instructed to avoid prejudice (Experiment 3). Results are consistent with shared reality theory, which postulates that social regulation is central to social cognition. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
84.
Welter R. Sessa W.B. Maeda M.W. Wagner R.E. Curtis L. Young J. Lee T.P. Nanduri K. Kodera H. Koga Y. Barry J.R. 《Lightwave Technology, Journal of》1989,7(10):1438-1444
An experimental 155.52 Mb/s coherent broadcast network with 16 channels using a conventional distributed feedback (DFB) laser operating at 1540 nm is described. It includes absolute laser frequency stabilization, a fiber span of 74.4 km, and a balanced polarization-diversity single-filter frequency-shift keying (FSK) heterodyne receiver. At a channel spacing of 8.5 GHz a power penalty of 0.3 dB is incurred due to adjacent channel crosstalk 相似文献
85.
Young W. Jeon Christine W. Curtis Blair A. Coker 《Petroleum Science and Technology》1997,15(9):873-905
The adsorption behavior of two asphalts and their size exclusion chromatography (SEC) fractions from toluene solution onto aggregate was investigated. The effect of the differences in chemistry and molecular size of the asphalt samples on their adsorption behavior on silica, granite and greywacke was determined. The adsorption of asphalts and SEC fractions on SI-1000 silica was well-represented by the Toth model, while the Radke-Prausnitz model better described their adsorption behavior on both granite and greywacke. Combining the adsorption models with the Gibbs adsorption equation of state gave the spreading pressure of each adsorbate species adsorbed on the aggregate surfaces. The spreading pressure predicted the competitive adsorptive edge of the asphalt fractions. The SEC I fractions, containing molecules of larger molecular size and higher heteroatom contents, showed higher spreading pressures than the SEC II fractions, which contained molecules of smaller molecular size and fewer heteroatoms. The asphalts yielded intermediate spreading pressures for SI-1000 silica and granite, but they gave the highest spreading pressure values for greywacke. 相似文献
86.
An experimental and theoretical study of multiple-beam interference effects at oblique endface airgap joints, with endfaces oriented parallel to each other, is discussed. It was found that although excellent return loss performance can be obtained by using such joints, large variations in the transmitted power can result in small changes in endface separation. Compared to the case of nonoblique endfaces, endface separation between the successive fringes in oblique endfaces increases by a factor which depends on the oblique angle and the refractive index of the gap material 相似文献
87.
The use of multiple predictor smoothing methods in sampling-based sensitivity analyses of complex models is investigated. Specifically, sensitivity analysis procedures based on smoothing methods employing the stepwise application of the following nonparametric regression techniques are described in the first part of this presentation: (i) locally weighted regression (LOESS), (ii) additive models, (iii) projection pursuit regression, and (iv) recursive partitioning regression. In this, the second and concluding part of the presentation, the indicated procedures are illustrated with both simple test problems and results from a performance assessment for a radioactive waste disposal facility (i.e., the Waste Isolation Pilot Plant). As shown by the example illustrations, the use of smoothing procedures based on nonparametric regression techniques can yield more informative sensitivity analysis results than can be obtained with more traditional sensitivity analysis procedures based on linear regression, rank regression or quadratic regression when nonlinear relationships between model inputs and model predictions are present. 相似文献
88.
A study was made of the mechanical properties and impact performance of carbon fibre/PEEK (0,90), () and () laminates and comparisons were made with similar carbon fibre/epoxy laminatesFibre dominated properties such as plain tensile strength were similar to those of epoxy laminates with similar fibres and volume fractions. Because of the increased toughness of PEEK there was less extensive matrix cracking, even though there was fibre debonding, and this gave increased transverse and shear cracking strains, increased shear strengths but decreased notched tensile strengths. The lower modulus and yield stress of PEEK caused lower compressive strengths, but PEEK absorbed little moisture and at 120°C moisture had little effect on mechanical properties.Dropweight impact produced less extensive damage in carbon fibre/PEEK laminates. Residual tensile strengths were similar but, because of the less extensive damage and greater delamination fracture energy, the residual compressive strengths were significantly greater with a PEEK matrix.Microscopic examination showed less matrix cracking and more fibre buckling in the carbon fibre/PEEK and this is discussed in relation to mechanical properties. 相似文献
89.
The effect of surface modification of aluminum powder on its flowability, combustion and reactivity 总被引:1,自引:0,他引:1
Surface modification of aluminum powders for the purpose of flow improvement was performed and several samples were prepared. Correlations between the flowability and reactivity for these powders as well as for the initial untreated aluminum powder were established. The powders were characterized using Scanning Electron Microscope (SEM), particle size distribution, angle of repose flowability test, Constant Volume Explosion (CVE) combustion test, and Thermo-Gravimetric Analysis (TGA). The surface modification of micron-sized aluminum powders was done by: (1) dry coating nano-particles of silica, titania and carbon black onto the surface of spherical aluminum powders and (2) chemically and physically altering the surface properties of the same powders with methyltrichlorosilane. All surface modifications improved flowability of the powders. CVE measurements indicate that powders with an improved flowability exhibit improved combustion characteristics if the powder treatment does not add an inert component to aluminum. The TGA results do not show significant differences in the reactivity of various powders. Based on combined flowability and CVE characteristics, the silane modified material gave the best results followed by the powders dry coated with carbon, titania and silica, respectively. 相似文献
90.
Danler RJ Boyle EA Kastner CL Thippareddi H Fung DY Phebus RK 《Journal of food protection》2003,66(3):501-503
Cooked, chilled beef and cooked, chilled pork were inoculated with three strains of Clostridium perfringens (NCTC 8238 [Hobbs serotype 2], NCTC 8239 [Hobbs serotype 3], and NCTC 10240). Inoculated products were heated to 75 degrees C, held for 10 min in a circulating water bath to heat activate the spores, and then chilled by circulating chilled brine through the water bath. Samples were chilled from 54.4 to 26.6 degrees C in 2 h and from 26.6 to 4.4 degrees C in 5 h. Differences in initial C. perfringens log counts and log counts after chilling were determined and compared with the U.S. Department of Agriculture (USDA) stabilization guidelines requiring that the chilling process allow no more than 1 log total growth of C. perfringens in the finished product. This chilling method resulted in average C. perfringens increases of 0.52 and 0.68 log units in cooked beef and cooked pork, respectively. These log increases were well within the maximum 1-log increase permitted by the USDA, thus meeting the USDA compliance guidelines for the cooling of heat-treated meat and poultry products. 相似文献