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101.
The Trail Making Test [TMT, R. M. Reitan, (see record 1960-00397-001), 1992] is extensively used in research in neuropsychology and in aging, in part because it has been postulated to reflect executive processes, such as planning and switching. However, neurocognitive and individual-difference based analyses of this test are complicated because of different spatial arrangements of targets, the use of letters only in Version B, and potential order effects when Version A is administered prior to Version B. The present article examines a variant of a TMT (called the Connections Test) that attempts to remedy these deficiencies. A structural equation model suggested that there were no direct effects of age on either the nonalternating or alternating versions of the Connections Test (analogous to TMT Versions A and B, respectively); rather, all age-related effects were mediated through effects on perceptual speed. Moreover, although the nonalternating and alternating versions were strongly related to one another, only the latter had significant independent relations with measures of higher order cognition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
102.
Women's World Cup is one of the most significant events for girls and women in sports this century. The importance of mental skills for athletic success is certainly not new. Coaches and participants in every sport extol the importance of the four pillars of sport essential to competitive excellence—technical (requisite skills of a sport), tactical (strategies used), physiological (physical requirements), and psychological (mental skills). Most, however, focus almost exclusively on the first three dimensions. At its core, sport psychology addresses the psychological factors that influence performance in sport and the effects of that participation on the individual. Psychological skills mirror physical training parameters, As psychological skills are developed and refined with consistent, qualified, and systematic training, the benefits accruing from such training increase over the years. Although a majority of the members of the 1999 women's soccer team have been in psychological skills training for 4 or more years, several are early in their skills training development. Psychological skills training includes relaxation techniques, imagery, concentration and distraction control strategies, prepractice and precompetition preparation, positive self-talk and performance cues, goal setting, and team building. No counseling occurs from a clinical standpoint. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Emerging adulthood (ages 18–25) is a critical period for neurobiological development and the maturation of the hypothalamic–pituitary–adrenal axis. Recent findings also suggest that a natural perturbation of the gut microbiota (GM), combined with other factors, may create a unique vulnerability during this period of life. The GM of emerging adults is thought to be simpler, less diverse, and more unstable than either younger or older people. We postulate that this plasticity in the GM suggests a role in the rising mental health issues seen in westernized societies today via the gut–brain–microbiota axis. Studies have paid particular attention to the diversity of the microbiota, the specific function and abundance of bacteria, and the production of metabolites. In this narrative review, we focus specifically on diet, physical activity/exercise, substance use, and sleep in the context of the emerging adult. We propose that this is a crucial period for establishing a stable and more resilient microbiome for optimal health into adulthood. Recommendations will be made about future research into possible behavioral adjustments that may be beneficial to endorse during this critical period to reduce the probability of a “dysbiotic” GM and the emergence and severity of mental health concerns.  相似文献   
105.
ABSTRACT

Ion-specific media (ISM) have played an integral role in the clean-up and remediation efforts at the Fukushima Dai-ichi disaster site, through the processing of contaminated wastewaters. The use of these materials generates a secondary nuclear waste stream, presenting its own series of engineering problems arising from stringent handling and long-term storage requirements. A reactive spark plasma sintering (SPS) method was investigated for conditioning of the spent cesium exchanged zeolite, chabazite. A natural form of the zeolite was used as an analogue to the engineered ISM used at the Fukushima NPP site. Simulant wasteforms were sintered using different temperature and pressure parameters followed by analysis of phase assemblage, density, and durability (using the product consistency test (PCT)). The results indicated that zeolite structure had collapsed completely, with the exchanged cesium partitioned primarily into a durable feldspar to assure stability of the sintered material for passively safe storage or geological disposal.  相似文献   
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A number of theorists have argued that the productive naming explosion results from advances in abilities that underlie language learning (e.g., the realization that words are symbols, changes in conceptual structure, or the onset of word learning constraints). If any of these accounts are accurate, there should be parallel developments in comprehension. To explore this issue, 4 studies assessed whether pre- and postnaming explosion children differ in their ability to learn a new word after limited exposure. 13- and 18-mo-olds heard a new object label just 9 times in a 5-min training session and then their comprehension was assessed in a multiple-choice procedure. Under favorable testing conditions, both 18- and 13-mo-olds showed comprehension of the new word, even after a 24-hr delay. These results suggest that well before the productive naming explosion, children can learn a new object label quickly. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
109.
Nonfamous names presented once in an experiment are mistakenly judged as famous 24 hr later. On an immediate test, no such false fame occurs. This phenomenon parallels the sleeper effect found in studies of persuasion. People may escape the unconscious effects of misleading information by recollecting its source, raising the criterion level of familiarity required for judgments of fame, or by changing from familiarity to a more analytic basis for judgment. These strategies place constraints on the likelihood of sleeper effects. We discuss these results as the unconscious use of the past as a tool vs its conscious use as an object of reflection. Conscious recollection of the source of information does not always occur spontaneously when information is used as a tool in judgment. Rather, conscious recollection is a separate act. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
110.
This report addresses the early detection of small steam generator tube leaks in pressurized water reactors. It discusses the third, and final, year's work on an NRC-funded project examining diagnostic instrumentation in water reactors. The first two years were broad in coverage, concentrating on anticipatory measurements for detection of potential problems in both pressurized- and boiling-water reactors, with recommendations for areas of further study. One of these areas, the early detection of small steam tube leaks in pressurized water reactors (PWRs), formed the basis of study for the last year of the project.Four tasks are addressed in this study of the detection of steam tube leaks.
1. (1) Determination of which physical parameters indicate the onset of steam generator tube leaks.
2. (2) Establishing performance goals for diagnostic instruments which could be used for early detection of steam generator tube leaks.
3. (3) Defining the diagnostic instrumentation and their location which satisfy Items 1 and 2 above.
4. (4) Assessing the need for diagnostic data processing and display.
Parameters are identified, performance goals established, and sensor types and locations are specified in the report, with emphasis on the use of existing instrumentation with a minimum of retrofitting. A simple algorithm is developed which yields the leak rate as a function of known or measurable quantities. The conclusion is that leak rates of less than one-tenth gram per second should be detectable with existing instrumentation.  相似文献   
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