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991.
[Correction Notice: An erratum for this article was reported in Vol 14(4) of Psychological Methods (see record 2009-22665-007). In this article, the authors wrote, To our knowledge, the multisample framework is the only available option within these [latent variable] programs that allows for the moderation of all types of parameters, and this approach requires a single categorical moderator variable to define the samples.” Bengt Muthén has clarified for the authors that some programs, including Mplus and Mx, can allow for continuous moderation through the implementation of nonlinear constraints involving observed variables, further enlarging the class of MNLFA models that can be fit with these programs.] When conducting an integrative analysis of data obtained from multiple independent studies, a fundamental problem is to establish commensurate measures for the constructs of interest. Fortunately, procedures for evaluating and establishing measurement equivalence across samples are well developed for the linear factor model and commonly used item response theory models. A newly proposed moderated nonlinear factor analysis model generalizes these models and procedures, allowing for items of different scale types (continuous or discrete) and differential item functioning across levels of categorical and/or continuous variables. The potential of this new model to resolve the problem of measurement in integrative data analysis is shown via an empirical example examining changes in alcohol involvement from ages 10 to 22 years across 2 longitudinal studies. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
992.
Although several studies have examined the neural basis for age-related changes in objective memory performance, less is known about how the process of memory monitoring changes with aging. The authors used functional magnetic resonance imaging to examine retrospective confidence in memory performance in aging. During low confidence, both younger and older adults showed behavioral evidence that they were guessing during recognition and that they were aware they were guessing when making confidence judgments. Similarly, both younger and older adults showed increased neural activity during low- compared to high-confidence responses in the lateral prefrontal cortex, anterior cingulate cortex, and left intraparietal sulcus. In contrast, older adults showed more high-confidence errors than younger adults. Younger adults showed greater activity for high compared to low confidence in medial temporal lobe structures, but older adults did not show this pattern. Taken together, these findings may suggest that impairments in the confidence–accuracy relationship for memory in older adults, which are often driven by high-confidence errors, may be primarily related to altered neural signals associated with greater activity for high-confidence responses. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
993.
We considered the role of community-based public mental health services in providing care to older persons with Alzheimer's disease and other forms of dementia, and examined service outcomes within California's county-based public mental health system over a 3-year period. Treated prevalence rates, repeat service use rates, and service mix patterns were regressed onto individual, market, and contextual variables across 25 counties over 12 observation periods. The number of older adults with dementia who used community mental health services increased slightly over the observation periods, and service use was associated with age and Medicaid status. Service outcomes also were affected by complementary mental health and aging service systems within each county, as well as the poverty rate and location of the county. Future research is needed to clarify how administrative policies and service management practices contribute to increasing community mental health service use by persons with dementia. In the meantime, these findings can help program administrators and service providers understand the role of community-based mental health services in providing care to persons with dementia. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
994.
More than 3,000 individuals from 7 U.S. cities reported on their memories of learning of the terrorist attacks of September 11, as well as details about the attack, 1 week, 11 months, and/or 35 months after the assault. Some studies of flashbulb memories examining long-term retention show slowing in the rate of forgetting after a year, whereas others demonstrate accelerated forgetting. This article indicates that (a) the rate of forgetting for flashbulb memories and event memory (memory for details about the event itself) slows after a year, (b) the strong emotional reactions elicited by flashbulb events are remembered poorly, worse than nonemotional features such as where and from whom one learned of the attack, and (c) the content of flashbulb and event memories stabilizes after a year. The results are discussed in terms of community memory practices. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
995.
Learning to recognize the contrasts of a language-specific phonemic repertoire can be viewed as forming categories in a multidimensional psychophysical space. Research on the learning of distributionally defined visual categories has shown that categories defined over 1 dimension are easy to learn and that learning multidimensional categories is more difficult but tractable under specific task conditions. In 2 experiments, adult participants learned either a unidimensional or a multidimensional category distinction with or without supervision (feedback) during learning. The unidimensional distinctions were readily learned and supervision proved beneficial, especially in maintaining category learning beyond the learning phase. Learning the multidimensional category distinction proved to be much more difficult and supervision was not nearly as beneficial as with unidimensionally defined categories. Maintaining a learned multidimensional category distinction was only possible when the distributional information that identified the categories remained present throughout the testing phase. We conclude that listeners are sensitive to both trial-by-trial feedback and the distributional information in the stimuli. Even given limited exposure, listeners learned to use 2 relevant dimensions, albeit with considerable difficulty. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
996.
The paper summaries portions of work of the Structural Aging Program, sponsored by the Nuclear Regulatory Commission (NRC). The paper addresses the assessment and repair of concrete structures in nuclear power plants. It presents the results of a survey of the the nuclear power plants in the United States to identify susceptible concrete components, rates of occurrence of deterioration, and to determine the durability of repairs. The paper describes deterioration mechanisms and discusses their effect. Repair techniques are described. Evaluation techniques and nondestructive test techniques are also discussed.  相似文献   
997.
998.
A total of 149 elderly men and women with pruritic skin problems were selected for study at the dermatological clinic in the Department of Medicine, Rajavithi General Hospital, Bangkok, Thailand, from 26 November 1996 to 10 January 1997. There were 62 men (41.6%) and 87 women (58.4%). The average age was seventy years. Among these elderly patients, pruritic skin disease was the most common problem, found in about 41%. Xerosis (senile pruritus) was the most common problem at 38.9%. Other pruritic skin diseases found were inflammatory eczema (22.8%), lichen simplex chronicus (12.1%), skin infections (11.4%), psoriasis vulgaris (6.7%), urticaria (4.7%), drug rash (2%), insect bite (0.7%), and anogenital pruritus (0.7%). Xerosis usually occurred with increased bathing frequency and use of strong soaps and detergents. The causes of inflammatory eczema were seborrheic dermatitis, allergic contact dermatitis, dyshidrosis, and stasis dermatitis. Statistical analysis of xerosis and inflammatory eczema by gender showed no difference, but there was more inflammatory eczema among females.  相似文献   
999.
1000.
The objective of this study was to empirically disentangle role perceptions related to organizational citizenship behavior (OCB) that have been confounded in past research, investigate their unique relationships with both an affiliative (helping) and a challenging (taking charge) form of OCB, and determine their relative importance in explaining these 2 forms of OCB. The authors also examined whether role discretion and role breadth independently moderate the procedural justice-to-OCB relationship. The authors surveyed 225 engineers in India and their direct supervisors. The results showed that 3 of the 4 facets of OCB role perception explain unique variance in either helping or taking charge, and that role breadth moderates the relationships between procedural justice and both helping and taking charge. The authors discuss implications of these findings for OCB theory and research, as well as for managerial practice. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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