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101.
Effects of long-term vocabulary instruction on lexical access and reading comprehension. 总被引:2,自引:0,他引:2
Beck Isabel L.; Perfetti Charles A.; McKeown Margaret G. 《Canadian Metallurgical Quarterly》1982,74(4):506
To examine the relationship between knowledge of word meanings and semantic processes, 27 4th-grade children were taught 104 words over a 5-mo period. Following instruction, Ss performed tasks designed to require semantic processes ranging from single word semantic decisions to simple sentence verification and memory for connected text. On all these tasks, instructed Ss performed at a significantly higher level than controls matched on pre-instruction vocabulary knowledge and comprehension. Thus, instructed Ss gave evidence both of learning word meanings taught by the program and of being able to process instructed words more efficiently in tasks more reflective of comprehension. Implications for vocabulary instruction and the role of individual word meanings in comprehension are discussed. (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
102.
Naditch Murray P.; Gargan Margaret A.; Michael Laurie B. 《Canadian Metallurgical Quarterly》1975,84(1):1
Reformulated a number of clinical observations about depression to test them empirically, using multiple regression equations. Ss were 547 men in Army basic training. Psychological measures included the Depression subscale of the Cornell Medical Index, Rotter's Internal-External Control Scale, the Institute for Personality and Ability Testing Anxiety Scale, N. Hahn's denial measure, and the Cantril Self-Anchoring Striving Scale. Depression was negatively correlated with denial and positively correlated with anxiety, locus of control, and the discrepancy between aspirations and achievements (discontent). Locus of control was positively correlated with discontent and anxiety and negatively correlated with denial. There were interaction effects between locus of control and discontent, between locus of control and anxiety, and between anxiety and denial when these terms were regressed on depression. (34 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
103.
Clarkin John F.; Widiger Thomas A.; Frances Allen; Hurt Stephen W.; Gilmore Margaret 《Canadian Metallurgical Quarterly》1983,92(3):263
Based on interview data from 76 18–45 yr old outpatients, the implications of a prototypic rather than a classical model of personality-disorder classification were demonstrated for DSM-III Axis II Borderline Personality Disorder (BPD). Heterogeneity of membership is described, and conditional probabilities are used to demonstrate the relative efficiency of single diagnostic criteria and combinations of criteria and the degree of overlap among BPD and other personality disorders. The conditional probability approach can be used to determine empirically the covariation of symptoms and to link the study of prototypicality to the individual patient rather than to the group. (17 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
104.
A steam-volatile extract, possessing a strong mushroom-like odour, has been isolated from Agaricus bisporus, the cultivated white mushroom of the mushroom grower. The major volatile components present, viz., 3-methylbutanal, 3-octanone, oct-1-en-3-one, 3-octanol, oct-1-en-3-ol, furfural, benzaldehyde, phenylacetaldehyde and benzyl alcohol, were identified by combined gas chromatography-mass spectrometry, and several other components were either positively or tentatively identified. The properties of the mushroom-like odour of oct-1-en-3-one and of the corresponding alcohol in dilute aqueous solution were examined. 相似文献
105.
106.
Bartlet E Blight MM Pickett JA Smart LE Turner G Woodcock CM 《Journal of chemical ecology》2004,30(5):913-925
The pollen beetle, Meligethes aeneus, which is an important pest of oilseed rape, Brassica napus, and turnip rape, B. rapa var. campestris, does not oviposit in all species of the Brassicaceae. The relationship between M. aeneus and candytuft, Iberis amara (Brassicacae), was investigated as part of chemical ecological studies into the development of control methods employing non-host-derived repellents. In choice and nonchoice feeding tests, M. aeneus completely rejected I. amara. However, in a field experiment using traps baited with flowering racemes of I. amara and B. napus, M. aeneus was attracted to both species. Gas chromatographic (GC) and GC-electroantennogram (GC-EAG) analyses indicated that the profiles of the floral volatiles of the two species are different. At least 12 compounds among the I. amara floral volatiles were detected by the M. aeneus antenna, and, of these, hexanoic acid, (E)-4,8-dimethyl-1,3,7-nonatriene and alpha-cedrene were not found among B. napus flower volatiles. Since M. aeneus is stimulated by floral volatiles to approach I. amara, but rejects it near, or at, the plant surface, I. amara does not produce repellents that could be used to manipulate M. aeneus. However, it may contain feeding deterrent(s) that could be used in "push-pull" control techniques or in the development of resistant brassicaceous crops. 相似文献
107.
Poly(vinylalcohol) (PVA)-stabilized silver nanoparticles were prepared by a seeding method. Nanoparticles of varying morphology were obtained by controlled variation of the reaction conditions, and this method allowed the tailoring of the position of the surface plasmon resonance. The samples show two bands in the visible absorption spectrum: one in the 410-440-nm region and a second peak between 500 and 600 nm. This tunable surface plasmon resonance serves to increase the third-order optical nonlinearity (chi 3) of the nanoparticles (measured at 532 nm) by a factor of 16. 相似文献
108.
Administered relational size problems in the context of ordinal series to 72 4-5 yr olds. Solution was facilitated when Ss were directed to locate a terminal member (the smallest) of the series. In contrast, Ss who were instructed to locate a nonterminal member without prior designation of a terminal member were unable to achieve solution of the problem. Age- and sex-related differences in performance were observed as well as differences associated with stimulus arrangements and stimulus sizes. The outcomes are discussed in terms of composite task demands. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
109.
The relationship between government actions and innovation in environmental control technology is important for the design of cost-effective policies to achieve environmental goals. This paper examines such relationships for the case of sulfur dioxide control technology for U.S. coal-fired power plants. The study employs several complementary research methods, including analyses of key government actions, technology patenting activity, technology performance and cost trends, knowledge transfer activities, and expert elicitations. Our results indicate that government regulation appears to be a greater stimulus to inventive activity than government-sponsored research support alone, and that the anticipation of regulation also spurs inventive activity. Regulatory stringency focuses this activity along particular technical pathways and is a key factor in creating markets for environmental technologies. We also find that with greater technology adoption, both new and existing systems experience notable efficiency improvements and capital cost reductions. The important role of government in fostering knowledge transfer via technical conferences and other measures is also seen as an important factor in promoting environmental technology innovation. 相似文献
110.