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81.
Lahey Benjamin B.; Loeber Rolf; Burke Jeffrey D.; Applegate Brooks 《Canadian Metallurgical Quarterly》2005,73(3):389
It is essential to identify childhood predictors of adult antisocial personality disorder (APD) to target early prevention. It has variously been hypothesized that APD is predicted by childhood conduct disorder (CD), attention-deficit/hyperactivity disorder (ADHD), or both disorders. To test these competing hypotheses, the authors used data from a single childhood diagnostic assessment of 163 clinic-referred boys to predict future APD during early adulthood. Childhood Diagnostic and Statistical Manual of Mental Disorders (3rd ed., rev.; American Psychiatric Association, 1987) CD, but not ADHD, significantly predicted the boys' subsequent APD. An interaction between socioeconomic status (SES) and CD indicated that CD predicted APD only in lower SES families, however. Among children who met criteria for CD, their number of covert but not overt CD symptoms improved prediction of future APD, controlling for SES. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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In recent years the processing speed of computers has increased dramatically. This in turn has allowed search algorithms to execute more iterations in a given amount of real-time. Does this necessarily always lead to an improvement in the quality of final solutions? This paper is devoted to the investigation of that question. We present two variants of local search where the search time can be set as an input parameter. These two approaches are: a time-predefined variant of simulated annealing and an adaptation of the “great deluge” method. We present a comprehensive series of experiments which show that these approaches significantly outperform the previous best results (in terms of solution quality) on a range of benchmark exam timetabling problems. Of course, there is a price to pay for such better results: increased execution time. We discuss the impact of this trade-off between quality and execution time. In particular we discuss issues involving the proper estimation of the algorithm's execution time and the assessment of its importance. 相似文献
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S. Meier N.V. Priest C.R. Burke J.K. Kay S. McDougall M.D. Mitchell C.G. Walker A. Heiser J.J. Loor J.R. Roche 《Journal of dairy science》2014
Previous research results have indicated an increase in pregnancy rate in pasture-grazed cows treated with a nonsteroidal antiinflammatory drug (NSAID) 3 to 4 wk postcalving, when a high proportion of nucleated cells from within the uterus were polymorphonucleated; however, no effect on milk production was detected. It was hypothesized that this lack of effect on milk production was because the administration of the NSAID was too late after calving. The aims of the current study were to evaluate the timing of administering a propionic acid-derived NSAID (i.e., carprofen) on milk production, metabolic status, uterine health, and reproductive performance. Six-hundred and thirty-nine cows (134 primiparous and 505 multiparous) calving between July 4 and September 5, 2012, in 2 herds (herd 1: n = 228; herd 2: n = 411) were enrolled. Using a randomized block design, cows were allocated to 1 of 3 treatment groups as they calved: (1) no treatment (control; n = 221), (2) NSAID administered on d 1, 3, and 5 postcalving (early; n = 214), and (3) NSAID administered on d 19, 21, and 23 postcalving (late; n = 204). Milk production and composition, and body condition were determined weekly. Blood was sampled at 4 time points (1 precalving and 3 postcalving) to determine the effects of treatment on indicators of metabolic health and energy status. Uterine health was determined by measuring the proportion of nucleated cells that were polymorphonucleated following cytobrush sampling of the uterus between d 13 to 24 and d 30 to 49 postcalving. Irrespective of timing of application, NSAID did not affect milk production, body weight, or body condition during early lactation. Treatment with an NSAID 19 to 23 d postcalving increased the proportion of cows submitted for breeding during the first 3 wk of the seasonal breeding program (control: 85%, early: 83%, and late: 92%), but did not affect conception or pregnancy rates. No detectable effect of treatment on uterine health or circulating metabolites and minerals existed, although cows in the early NSAID treatment group had marginally lower serum β-hydroxybutyrate concentrations (0.1 mmol/L) than the other groups between 2 and 26 d in milk. In conclusion, administration of this particular NSAID at either 1 or 3 wk after calving did not improve milk production, indicators of health, or reproductive performance. 相似文献
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The assumption with the biggest impact on the design of geosynthetic-reinforced soils above voids is the presence and degree of soil arching, which affects the predicted applied stress on the geosynthetic. A series of centrifuge tests were conducted to investigate the soil arching in geosynthetic-reinforced soils with measurements of the soil stresses and observation of soil and geosynthetic deformation used to infer the arching behaviour. Detailed analysis of the results showed that arching significantly reduces the stress at the base of the soil when a void forms; this mechanism is due to stress redistributions and not the formation of a physical arch as suggested in some models. A new method to reliably predict this reduction is proposed by calculating the coefficient of lateral stress on vertical failure planes based on the observations of a continuous convex arc of major principal strains above the void, and the assumption that this is indicative of the stress behaviour. 相似文献
89.
A. R. Boyd C. O’Kane P. O’Hare G. A. Burke B. J. Meenan 《Journal of materials science. Materials in medicine》2013,24(12):2845-2861
The nature of the initial interaction between calcium phosphate (Ca–P) thin films and osteoblasts can be influenced by a number of different properties including the phase, crystallinity, stoichiometry and composition of the surface. There is still a strong interest in developing and studying Ca–P surfaces that have the ability to accurately control the osteoblast response. Radio frequency (RF) magnetron sputtering is a technique that allows for accurate control of the properties of deposited Ca–P coatings and has been studied extensively because of this fact. In this work, Ca–P coatings were co-deposited using RF magnetron sputtering in order to study the effect of changing the target stoichiometry on the initial in vitro behavior of MG63 osteoblast-like cells. The samples produced were analysed both as-deposited and after thermal annealing to 500 °C. After annealing XPS analyses of the samples co-deposited using tricalcium phosphate (TCP) materials gave a Ca/P ratio of 1.71 ± 0.01, as compared to those co-deposited from hydroxyapatite (HA) materials, with a Ca/P of 1.82 ± 0.06. In addition to this, the curve fitted XPS data indicated the presence of low levels of carbonate in the coatings. Despite this the XRD results for all of the annealed coatings were shown to be characteristic of pure HA with a preferred 002 orientation. The atomic force microscopy results also highlighted that both types of coatings had surface features of a similar size (200–220 nm). Both surfaces exhibited a degree of surface degradation, even after 1 h of cell culture. However, the TCP derived surfaces showed an enhanced osteoblastic cell response in terms of cell adhesion and cell proliferation in the earlier stages of cell culture than the surfaces deposited from HA. An improvement in the initial cell attachment and a potential for increased cell proliferation rates is viewed as a highly advantageous result in relation to controlling the osteoblast response on these surfaces. 相似文献
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