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61.
We evaluated the data of the National Collegiate Athletic Association Injury Surveillance System on collegiate wrestling with a focus on musculoskeletal injuries. Over 800,000 athlete-exposures during an 11-year period compose these data. Findings particular to wrestling and a comparison with other collegiate sports are included. Collegiate wrestling had a relatively high rate of injury at 9.6 injuries per 1000 athlete-exposures. It was second to spring football in total injury rate. Most injuries in this study were not serious, with 6.3% resulting in surgery and 37.6% resulting in a week or more off from wrestling. There was only one catastrophic, nonfatal injury. The knee, shoulder, and ankle were the most commonly injured regions, and injuries to them were often the more serious. Sprains, strains, and contusions were the most common injury types. Takedowns and sparring were the most common activities at the time of injury. Mechanism of injury was evaluated; rotation about a planted foot and contact with environmental objects were identified as areas needing further attention. Illegal action accounted for only 4.6% of injuries in competition. Competition had a significantly higher injury rate than practice, but the injury profiles of these two areas showed both to be equally important. The preseason and regular season had higher injury rates than the postseason, but, again, the injury profiles of these periods were similar. Injury percentages were similar among the 10 weight classes.  相似文献   
62.
Immobilization bone loss, whether due to whole body immobilization or local causes, is associated with an initial rapid phase of trabecular bone loss, but the long-term effects of immobilization on cortical bone are not well described. We have studied metacarpal morphometry in 16 men who had undergone partial or complete traumatic digital amputations 4-71 years earlier. Noninvolved metacarpals from the affected and unaffected hands were used as controls. Cortical bone width was significantly reduced in the metacarpals proximal to the amputated digits (P = 0.001). In the 7 subjects who suffered amputation before the age of 19, the cortical bone deficit was primarily due to a reduction in the total width of the medullary shaft (P = 0.007), whereas medullary width was not changed. In these subjects the metacarpal was also significantly reduced in length, by a mean 2.9 mm (P = 0.35). In the 9 subjects who had their amputation after the age of 19, both a reduction in total width and an increase in medullary width (P = 0.017) accounted for the cortical bone deficit. The deficit in total width was related to the time since amputation (P = 0.008) and could be accounted for by loss of the normal age-related increase in total width (0.01 mm/year). We conclude that in this model of immobilization osteoporosis, the metacarpal proximal to the amputated digit demonstrates cortical osteopenia.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
63.
The location of origins of DNA replication within the Saccharomyces cerevisiae genome is primarily determined by the origin recognition complex (ORC) interacting with specific DNA sequences. The analogous situation in vertebrate cells is far less clear, although ORC subunits have been identified in several vertebrate organisms including Xenopus laevis. Monoclonal antibodies were raised against Xenopus Orc1p and used for single-step immunoaffinity purification of the entire ORC from an egg extract. Six polypeptides ( approximately 110, 68, 64, 48, 43, and 27 kDa) copurified with Xenopus Orc1p. Protein sequencing also showed the 64-kDa protein to be the previously identified Xenopus Orc2p. Microsequencing of the 43- and 48-kDa proteins that copurified with Orc1p and Orc2p led to their identification as the Orc4p and Orc5p subunits, respectively. Peptide sequences from the 43-kDa protein also allowed the isolation of cDNAs encoding the Xenopus, mouse, and human ORC4 subunits. Human ORC5 was also cloned; its sequence displayed extensive homology to both Drosophila and yeast ORC5. Surprisingly, comparison of the amino acid sequences of Orc1p, Orc4p, and Orc5p suggests that they are structurally related to each other and to the replication initiation protein, Cdc6p. Finally, we present the sequence of the putative Xenopus and human Orc3p.  相似文献   
64.
65.
The partial-correlation approach to investigating negative affectivity (NA) is discussed, and 2 alternative latent-variable techniques are presented. The results of these 3 analytic techniques were compared using a data set consisting of NA, job satisfaction, affective commitment, role stressors, leader-member exchange, and job complexity. The findings using the partial-correlation technique supported a biasing effect of NA on relationships between the substantive variables. Alternatively, although 2 latent-variable approaches provided evidence consistent with the measurement contamination and substantive influences of NA, relationships between the predictors and outcomes were not biased by NA. Both the measurement and substantive relationships effects of NA found in this study and implications for future research on self-reports are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
66.
This paper fully develops a previous approach by George et al. (1993) to modeling uncertainty in class hierarchies. The model utilizes fuzzy logic to generalize equality to similarity which permitted impreciseness in data to be represented by uncertainty in classification. In this paper, the data model is formally defined and a nonredundancy preserving primitive operator, the merge, is described. It is proven that nonredundancy is always preserved in the model. An object algebra is proposed, and transformations that preserve query equality are discussed  相似文献   
67.
Deodorization is the final processing step in the production of edible oil products. Chemical/physical aspects of deodorization and mechanical design of deodorizers are explained, including chemical analysis of feedstock, finished product and by-products. This includes normal operating standards and means of correcting off specification operation. Operating procedures, labor requirements and maintenance are reviewed. Finished oil handling includes use of antioxidants, inert gas addition, pipelines and storage facilities. Emphasis is on the practical operations of deodorization and finished soybean oil handling.  相似文献   
68.
In the forest zone of Cameroon, small-scale family farmers practicing traditional slash and burn practices achieve a clear field by piled burning of the branches and trunks of cleared vegetation. Plant growth inhibition on ash patches, and the risk of nutrient loss from these areas, was evaluated on field plots on which 0.5 t m–2 or 1.0 t m–2 of wood was piled and burnt, and in laboratory studies. The ash produced by burning was strongly alkaline, and laboratory bio-assessment studies showed that the saline, high pH conditions produced in ash patches prevented germination and plant growth for up to two wet seasons, as is observed in the field. Field and laboratory studies demonstrated rapid release (1 wet season) of K and S from the ash and the loss of a substantial portion of these nutrients from the soil profile by leaching. In contrast, leaching carries Mg from the ash gradually (3 to 4 wet seasons), while Ca, Cu, Zn and P are leached slowly. The nutrients contained in ash patches are considered at risk of loss both through leaching (K and S) and by erosion of ash (Ca, Mg, Cu, Zn and P). Farmers should be encouraged to spread ash patches prior to cultivation in order to exploit the nutrient content of ash and to lessen the risk of nutrient loss.  相似文献   
69.
70.
A stochastic version of the standard nonlinear programming problem is considered. A functionf(x)is observed in the presence of noise, and we seek to minimizef(x)forx in C = {x:q^{i}(x) leq 0}, whereq^{i}(x)are constraints. Numerous practical examples exist. Algorithms are discussed for selecting a sequence Xnwhich converges wp 1 to a point where a necessary condition for optimality holds. The algorithms use, of course, noise-corrupted observations on thef(x). Numerical results are presented. They indicate that the approach is quite versatile, and can be a useful tool for systematic Monte-Carlo optimization of constrained systems, a much-neglected area. However, many practical problems remain to be resolved, e.g., investigation of efficient one-dimensional search methods and of the tradeoffs between the effort spent per search cycle and the number of search cycles.  相似文献   
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