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51.
聚乙烯醇膜的阻醇及导电性能(Ⅱ)戊二醛交联聚乙烯醇膜 总被引:3,自引:0,他引:3
为提高直接甲醇燃料电池(DMFC)用膜的阻醇性能,采用在渗透蒸发领域广泛使用且具有良好分离效果的聚乙烯醇(PVA)为主要材料,制备了戊二醛(GA)交联PVA膜,考察了此类膜的阻醇及质子导电能力。PVA(GA)膜的阻醇效果较目前在DMFC中广泛使用的Nation膜有显著提高,但其自身不具有质子导电能力,需外加电解质溶液以提高其电导率。 相似文献
52.
The effects of washing with hydrogen peroxide (H2O2) and sodium hypochlorite (NaOCl) solutions on the gel-forming ability and physicochemical properties of surimi produced from bigeye snapper (Priacanthus tayenus), stored in ice for up to 14 days, were investigated. Generally, pH and the trichloroacetic acid (TCA)-soluble peptide content of washed mince varied, depending on the type of oxidizing agent and storage time of the fish. With increasing time of storage, the pHs of water- and H2O2-washed mince were lower than that of NaOCl-washed mince (P < 0.05). However, no differences in the TCA-soluble peptide contents of the resulting mince washed with any media were observed (P > 0.05). Washing with 20 ppm NaOCl resulted in the highest increase in both the breaking force and the deformation of mince from fish stored in ice for all the times studied (P < 0.05). Natural actomyosin (NAM) extracted from NaOCl-washed mince had higher surface hydrophobicity and disulfide bond (SS) content than that of water-washed mince (P < 0.05). With no effect on Ca2+-, Mg2+-, or Mg2+–Ca2+-ATPase activities, NaOCl washing resulted in an increase in Mg2+–EGTA-ATPase activity of NAM (P < 0.05). The results suggested that washing mince with the appropriate type and concentration of oxidizing agent can improve the gelling ability of surimi, particularly from low quality fish. 相似文献
53.
54.
Judge Timothy A.; Jackson Christine L.; Shaw John C.; Scott Brent A.; Rich Bruce L. 《Canadian Metallurgical Quarterly》2007,92(1):107
The present study estimated the unique contribution of self-efficacy to work-related performance controlling for personality (the Big 5 traits), intelligence or general mental ability, and job or task experience. Results, based on a meta-analysis of the relevant literatures, revealed that overall, across all studies and moderator conditions, the contribution of self-efficacy relative to purportedly more distal variables is relatively small. Within moderator categories, there were several cases in which self-efficacy made unique contributions to work-related performance. For example, self-efficacy predicted performance in jobs or tasks of low complexity but not those of medium or high complexity, and self-efficacy predicted performance for task but not job performance. Overall, results suggest that the predictive validity of self-efficacy is attenuated in the presence of individual differences, though this attenuation does depend on the context. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
55.
In this paper, genetic algorithm is used to help improve the tolerance of feedforward neural networks against an open fault. The proposed method does not explicitly add any redundancy to the network, nor does it modify the training algorithm. Experiments show that it may profit the fault tolerance as well as the generalisation ability of neural networks. 相似文献
56.
Ten areas of health knowledge were investigated in 2 studies, 1 of college students (N=169) and 1 of adults from the community (ages 19-70; N=176). Measures assessed knowledge of aging, orthopedic/ dermatological concerns, common illnesses, childhood/early life, serious illnesses, mental health, nutrition, reproduction, safety, and treatment of illness/disease. Significant gender differences favoring women were found for most areas of health knowledge, especially reproduction and early life. Results showed that cognitive ability accounted for the most variance in health knowledge with nonability (personality and interest traits) and demographic variables accounting for smaller but significant amounts of variance across most knowledge domains. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
57.
This article reviews the theory of successful intelligence and attempts to construct-validate the theory of successful intelligence. It describes 4 distinct converging operations that have been used in these attempts. Two sets involve internal validation of the structure of the theory and 2 sets external validation of the theory with outside criteria. The internal validation operations involve information-processing (componential) analyses and both exploratory and confirmatory factor analyses. The external validation operations involve correlational analysis and analyses of instructional interventions based on the theory. The results are generally supportive of the theory and suggest that conventional conceptions of intelligence may be too narrow. The theory is of use in consulting because it broadens the scope of skills one looks for in seeking "intelligent" people for hiring, retention, and promotion and in assessing a person's ability to do his or her current job. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
58.
Yoshizaki Kazuhito; Weissman Daniel H.; Banich Marie T. 《Canadian Metallurgical Quarterly》2007,21(3):326
In the present study, we investigated whether a hemispheric division of labor is most advantageous to performance when lateralized inputs place unequal resource demands on the left and right cerebral hemispheres. In each trial, participants decided whether 2 rotated letters, presented either in the same visual field (within-field trials) or in opposite visual fields (across-field trials), were both of normal orientation, or whether one was normal and the other was mirror-reversed. To discriminate a letter's orientation, one must rotate the letter to the upright position. Therefore, we manipulated whether the two letters imposed similar or dissimilar demands on cognitive resources by varying the number of degrees that each letter needed to be rotated to reach the upright position. As predicted, in 2 experiments we found that the across-field advantage increased as the number of degrees each letter needed to be rotated became more dissimilar. These findings support a current model of hemispheric interactions, which posits that an unequal hemispheric distribution of cognitive load allows the cerebral hemispheres to take the lead for different aspects of cognitive processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
59.
蒸汽热采条件下支撑剂性能评价试验研究 总被引:2,自引:2,他引:0
在蒸汽热采条件下,支撑剂处于比较苛刻的应力、温度、化学环境中,支撑裂缝的导流能力除了与通常酸性环境中的闭合压力、支撑剂破碎率等因素有关外,还与蒸汽冷凝水和回采液碱蚀、高温所造成的物理化学变化有关.通过静、动态试验,研究和分析了在蒸汽热采条件下影响支撑剂性能的各种因素,同时给出了蒸汽热采稠油井水力压裂、压裂防砂支撑剂优选的基本原则. 相似文献
60.
Children between 7 and 8 years old took pan in a staged event at school and 1 week later were assessed using a short form of the Wechsler Intelligence scale for children (third edition) and measures of metamemory, narrative ability, and socioeconomic status. Two weeks following the event, children either received narrative elaboration training (NET; K.J. Saywitz & L. Snyder, 1996) and were prompted with the four NET cue cards at interview; received verbal prompts corresponding to the cue card categories, but without prior training; or were presented with the cards at interview without prior training. Children given verbal labels as prompts recalled as much information as children who received NET training and cue cards. Measures of intelligence were predictive of amount recalled for cards-only children but not for the other 2 groups, indicating that differences in recall between low- and high-IQ groups were attenuated when recall was supported by NET training or verbal prompting. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献