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101.
102.
Assigned 96 male undergraduates to small groups based on their scores on a 40-item self-report survey derived from the Self-Disclosure Questionnaire. Half the groups received an explicit self-disclosure contract while the other half received no contract. Findings show that (a) the contract served to increase significantly both the frequency and depth of self-disclosure but did not affect the level of intimacy of topics discussed; and (b) the contract significantly enhanced the cohesiveness of the groups (i.e., attraction to the group) but had the opposite effect on members' mutual liking. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
103.
Neil B. Milestone David M. Bibby 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1981,31(1):732-736
Silicalite, a zeolite analogue, selectively adsorbs organic molecules from aqueous solution, the adsorption depending on the stereochemistry and organophilic nature. This provides a possible economic route for the separation of alcohols from dilute solutions. Ethanol has been concentrated from a 2% (w/v) solution to 35%, and butan-1-ol from 0.5 to 98% (w/v) by adsorption on silicalite and subsequent thermal desorption. 相似文献
104.
Contends that most content analysts of psychotherapy materials have failed to consider the possibility that the frequency of units coded to the categories of the content analysis system might be correlated with the total number of units produced. The existence of such relationships may confound interpretation of the association between content analysis variables and other external variables. When investigators have attempted to control for response productivity, they have usually divided the frequency of units in each category by the total number of units. This procedure does not control for response productivity and is often uninterpretable. The issues involved are discussed and demonstrated, and appropriate techniques of controlling for productivity are described. (43 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
105.
106.
Gillian M. Keith Kumaravinothan Sarma Neil McN. Alford Derek C. Sinclair 《Journal of Electroceramics》2004,13(1-3):305-309
Hexagonal BaTiO3 materials have been stabilised at room temperature according to the formula BaTi0.95M0.05 O3– where M = Mn, Fe, Co and Ni. Dense ceramics (> 96% of the theoretical X-ray density) were sintered at 1450C in flowing O2 gas from calcined powders prepared by the mixed oxide route at 1300C. All samples were single-phase and the bulk conductivity, b, measured by Impedance Spectroscopy and Q.f measured by microwave dielectric resonance methods showed a strong dependence on the type of dopant. b at 300C was 10–7, 10–5.5, 10–5.5 and 10–4 Scm–1 for M = Mn, Fe, Ni and Co, respectively and Q.f at 5 GHz was 7790, 6670, 2442 and 1291 GHz, for M = Mn, Fe, Ni and Co, respectively. The correlation between b and Q.f is attributed to the presence of oxygen vacancies and/or mixed valency of the dopant ions. 相似文献
107.
Spatial analysis of annual air pollution exposure and mortality 总被引:1,自引:0,他引:1
Scoggins A Kjellstrom T Fisher G Connor J Gimson N 《The Science of the total environment》2004,321(1-3):71-85
The aim of this study was to relate ambient air pollution levels to mortality in Auckland, New Zealand. We used urban airshed modelling and GIS-based techniques to quantify long-term exposure to ambient air pollution levels and associated mortality. After adjusting for age, sex, ethnicity, socio-economic status, and urban/rural domicile there was a 1.3% (95%CI: 1-1.5%) increase in non-external cause mortality, and 1.8% (95%CI: 1.5-2.1%) increase in circulatory and respiratory causes per 1 microg/m(3) increase in annual average NO(2). Based on these exposure-response relationships and applying an annual average threshold of 13 microg/m(3), the average annual (for 1996-1999) number of people estimated to die from non-external causes and circulatory and respiratory causes attributable to air pollution in Auckland is 268 (95% range: 227-310) (3.9% of total all cause deaths) and 203 (95% range: 169-237) (5.9% of total circulatory and respiratory deaths) per year, respectively. The number of attributable deaths found in this study are consistent with a previous New Zealand risk assessment using a different methodology, and is approximately twice the number of people dying from motor vehicle accidents in the region, which is on average (1996-1999) 103 per year. The GIS-based exposure maps identify high exposure areas for policy developers and planners in a simple and realistic manner. Taken together with overseas studies the study provides additional evidence that long-term exposure to poor air quality, even at levels below current standards, is a hazard to the public health. 相似文献
108.
Macías D Vial A Barchiesi D 《Journal of the Optical Society of America. A, Optics, image science, and vision》2004,21(8):1465-1471
We introduce an inversion procedure for the characterization of a nanostructure from near-field intensity data. The method proposed is based on heuristic arguments and makes use of evolution strategies for the solution of the inverse problem as a nonlinear constrained-optimization problem. By means of some examples we illustrate the performance of our inversion method. We also discuss its possibilities and potential applications. 相似文献
109.
The purpose of this study was to apply a series of mathematical models in order to investigate the nature of the kinetic response to heavy intensity exercise with children and identify a suitable model with which to estimate parameters of the response. Sixty two children (35 male, 27 female aged 10-15 years) completed four transitions from baseline pedalling to 40% of the difference between their previously determined anaerobic threshold and peak VO2 on an electronically braked cycle ergometer. Initially three models were fitted to the averaged response profiles following the end of phase 1. and their residuals compared; 1, a single exponential with a delay term; 2, an exponential and linear term with independent delays; and 3, a double exponential with independent delays. Up to 95% of the response profiles were better fitted by either model 2 or 3 (p < 0.05), and model 3 was a statistically better fit (p < 0.05) than model 2 in 77% of cases. Residual inspection confirmed the superior fit by model 3. A fourth model which consisted of a single exponential with a delay term was fitted within the phase 2 fitting window. Estimated parameters (A1 and tau1), using model 4 were not significantly different from model 3, and model 4 was identified as the model of choice due to the wide confidence intervals in tau2 and A2 using model 3. It was concluded that the nature of the response to heavy intensity exercise in children is similar to that previously reported with adults and that the response should be modelled accordingly. 相似文献
110.
For improved detection of diverse posttranslational modifications (PTMs), direct fragmentation of protein ions by top down mass spectrometry holds promise but has yet to be achieved on a large scale. Using lysate from Saccharomyces cerevisiae, 117 gene products were identified with 100% sequence coverage revealing 26 acetylations, 1 N-terminal dimethylation, 1 phosphorylation, 18 duplicate genes, and 44 proteolytic fragments. The platform for this study combined continuous-elution gel electrophoresis, reversed-phase liquid chromatography, automated nanospray coupled with a quadrupole-FT hybrid mass spectrometer, and a new search engine for querying a custom database. The proteins identified required no manual validation, ranged from 5 to 39 kDa, had codon biases from 0.93 to 0.083, and were primarily associated with glycolysis and protein synthesis. Illustrations of gene-specific identifications, PTM detection and subsequent PTM localization (using either electron capture dissociation or known PTM data stored in a database) show how larger scale proteome projects incorporating top down may proceed in the future using commercial Q-FT instruments. 相似文献