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981.
The structure of three cross-linked polymers containing naphthalenic rings in their backbone structure was investigated by dynamic swelling and thermal analytic techniques. It was determined that the pyridine and n-proplyamine transport in microparticles (40 μm) of these polymers was non-Fickian, often approaching case II transport and sometimes even supercase II transport. The thermal analysis showed relatively stable structures up to about 350°C. 相似文献
982.
983.
Rheumatoid arthritis (RA) patients have been identified as a medical population at risk for psychological disorder, largely because of the pain and functional disability that are the hallmarks of the disease. This study examined the degree to which self-reported functional disability and coping efforts contribute to psychological adjustment among adult RA patients over a 6-month period. Adaptive outcomes included maintaining a sense of worth, mastery, and positive affect despite the illness. Hierarchical multiple regression analyses indicated that increases in disability were related to decreased acceptance of illness and increased negative affect. Coping efforts were related to increases in positive affect. The findings provide modest support for the role individual coping efforts play in shaping illness-related outcomes. Although disability is not easily reversed, knowledge about coping strategies that moderate its psychological impact may provide a useful basis for designing psychological interventions to promote adjustment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
984.
ME Blanchette RS Nanda GF Currier J Ghosh SK Nanda 《Canadian Metallurgical Quarterly》1996,109(2):116-131
The longitudinal growth and development of the soft tissue drape for boys and girls with long and short vertical patterns was examined from age 7 to 17 years. The sample was taken from the Denver Growth Study and consisted of 32 subjects who were selected on the basis of their percentage of lower anterior vertical face height. All subjects were of northern European ancestry, and none had undergone orthodontic treatment. The sexual dimorphism was evident as anticipated for several soft tissue measurements. The boys showed continued growth through age 16 years in contrast to the girls who attained the adult size of the soft tissue integument around 14 years. A significant difference between vertical facial patterns was reported for all soft tissue variables with the exception of the soft tissue thickness at A point and the upper lip height. The boys and girls with long vertical patterns exhibited a thicker and longer soft tissue drape for the most variables when compared with those with short facial patterns. These soft tissue differences are believed to be compensatory mechanisms in long-face subjects, which may attempt to mask the vertical dysplasia, thereby producing a more normal facial profile. Individual growth assessments revealed that the perioral soft tissues follow a pattern similar to that of the mean group patterns. The subjects with long vertical facial patterns experienced their pubertal growth spurt earlier than the short-face subjects. This may have clinical implications in the timing of orthodontic intervention and treatment. 相似文献
985.
Cole Pamela M.; Zahn-Waxler Carolyn; Fox Nathan A.; Usher Barbara A.; Welsh Jean D. 《Canadian Metallurgical Quarterly》1996,105(4):518
Emotion regulation (ER) was assessed during a negative mood induction in 79 preschoolers who varied in degree of behavior problems. Facial expressivity during the induction was used to identify 3 ER groups: inexpressive, modulated expressive, and highly expressive. Group differences in ER were significantly related to heart rate and skin conductance. Inexpressive preschoolers had the highest heart rate, lowest vagal tone, and smallest autonomic nervous system (ANS) change during the induction. Highly expressive preschoolers had the slowest heart rate, highest vagal tone, and largest ANS change. The inexpressive and highly expressive groups had more externalizing symptoms than the modulated group at preschool age and at follow-up at the end of 1st grade. Inexpressive preschoolers appeared to have more depressed and anxious symptoms at follow-up. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
986.
Psychologists working with young gay men and lesbians may experience public and agency resistance based primarily on the confusion of moral and rational thinking and on homophobia. To work effectively with young lesbians and gay men, psychologists need to be relatively free of homophobia and knowledgeable about gay male and lesbian life-styles. Provision of developmental process information to the client is very useful. Internal and external homophobia, a lack of healthful role models, coming out to oneself and others, and AIDS (acquired immune deficiency syndrome) are among the most critical problems faced by young gay men and lesbians. Although a discussion of intervention techniques is beyond the scope of this article, bibliotherapy is briefly described as one effective intervention in that it provides necessary information to the client and it serves as a springboard for therapy. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
987.
Proposes a motivational analysis to help account for individual (e.g., sex) differences in different academic areas (e.g., mathematical vs verbal areas). It is proposed that certain academic areas (e.g., mathematics) are more likely than others (e.g., verbal) to pose difficulties at the start of new units and that the necessity of surmounting difficulties favors certain achievement orientations. To test the hypothesis that children's academic orientations interact with the acquisition demands of academic material to determine performance, 57 male and 37 female 5th graders, who were classified as helpless or mastery oriented on the basis of their attributions, were assigned to 1 of 2 learning conditions. One condition involved programmed confusion during learning, while the other was a no-confusion condition. When the learning task contained somewhat confusing material in the initial sections (even though it was irrelevant to what was to be learned), Ss with a mastery oriented attributional style significantly outperformed those with a helpless style. However, when the identical task was presented without the confusing material, both groups learned with equal facility. Results support the notion that achievement differences can result from the fit between children's achievement orientations and the demands of particular skill areas. (44 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
988.
989.
The sensorimotor problems faced by animals and by robots have much in common, yet identifying this similarity has so far led to very few successful attempts to implement specific biological neural control structures on robots. One major limitation is that understanding of the biological mechanisms is insufficient for straightforward installation. However, using robots as a method of physically modeling animal systems can potentially contribute to our understanding of these mechanisms. This approach is employed in an investigation of phonotaxis (sound-seeking) in crickets. The process of building a robot forms the basis of a critical evaluation of the neuroethological evidence about the cricket, and generates an alternative hypothesis to explain this evidence. The explanatory power of this hypothesis is explored by testing and analyzing the behaviour of the robot that embodies it. The robot behaved like the cricket, competently and robustly finding its way to a specific sound source under a variety of conditions. It is argued that the methodology is more appropriate than symbolic simulation for the kinds of problems raised in the investigation of sensorimotor behaviour in animals and robots. 相似文献
990.