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101.
J A Brandon J Richards 《Proceedings of the Institution of Mechanical Engineers. Part H, Journal of engineering in medicine》1989,203(4):203-205
Time-domain tests for monitoring fracture healing, undertaken by the authors and workers elsewhere, show a repeatable characteristic signal behaviour which is difficult to explain using the linear models prevailing in biomechanics. The paper proposes a simple non-linear model which, it is believed, will reproduce the observed signal behaviour and is consistent with the biphasic stiffness model previously identified in static mechanical testing for monitoring of fracture healing. This, in turn, correlates with the two stages of callus formation in the accepted biological model. 相似文献
102.
The authors, Nigel Isaacs, Michael Donn and Dr George Baird of the School of Architecture, Victoria University of Wellington, present a succinct account of the practical difficulties they encountered when implementing recommendations from energy audits in a defined number of New Zealand schools. It is concluded that these difficulties relate more to funding and personnel than the engineering of the energy savings in themselves. 相似文献
103.
Roderich Gro? Alasdair I Houston Edmund J Collins John M McNamara Fran?ois-Xavier Dechaume-Moncharmont Nigel R Franks 《Journal of the Royal Society Interface》2008,5(27):1193-1202
We consider an agent that must choose repeatedly among several actions. Each action has a certain probability of giving the agent an energy reward, and costs may be associated with switching between actions. The agent does not know which action has the highest reward probability, and the probabilities change randomly over time. We study two learning rules that have been widely used to model decision-making processes in animals—one deterministic and the other stochastic. In particular, we examine the influence of the rules'' ‘learning rate’ on the agent''s energy gain. We compare the performance of each rule with the best performance attainable when the agent has either full knowledge or no knowledge of the environment. Over relatively short periods of time, both rules are successful in enabling agents to exploit their environment. Moreover, under a range of effective learning rates, both rules are equivalent, and can be expressed by a third rule that requires the agent to select the action for which the current run of unsuccessful trials is shortest. However, the performance of both rules is relatively poor over longer periods of time, and under most circumstances no better than the performance an agent could achieve without knowledge of the environment. We propose a simple extension to the original rules that enables agents to learn about and effectively exploit a changing environment for an unlimited period of time. 相似文献
104.
Christian Rößle Nigel Brunton Thomas R. Gormley Francis Butler 《International Journal of Food Science & Technology》2011,46(3):626-634
The effect of vacuum impregnation (VI) of fresh‐cut apple wedges with honey, in presence and absence of a browning inhibitor on physicochemical, sensory and antioxidant properties over 7 days of storage at 2–4 °C was studied. Infusion of wedges with honey resulted in very little weight change indicating loss of internal water and ingress of honey carbohydrates into the wedges, hence the correlation coefficients with soluble solids content (r = ?0.91) and dry matter (r = ?0.77). Water infused samples showed the highest water uptake resulting in an increase in weight of 30%. Browning (P < 0.001) and firmness (P < 0.001) of apple wedges were the quality parameters most affected by VI. Samples dipped in browning inhibitor prior AS1 showed slightly better performance than undipped wedges with regard to browning and firmness. Total phenol content and antioxidant activity were significantly (P < 0.001) lower for honey infused apple wedges. 相似文献
105.
Redding Richard E.; Herbert James D.; Forman Evan M.; Gaudiano Brandon A. 《Canadian Metallurgical Quarterly》2008,39(5):537
Self-help books for psychological disorders have become increasingly popular, yet there is surprisingly little research on their scientific status or overall utility. The authors identified 50 top-selling self-help books for anxiety, depressive, and trauma-related disorders. Using a scale derived from the literature on bibliotherapy, expert psychologists rated each book on overall usefulness, grounding in psychological science, the extent to which it offers reasonable expectations, the extent to which it offers specific guidance for implementing the self-help techniques and for monitoring treatment progress, and whether it offers potentially harmful advice. The results revealed strong intercorrelations among the scales, such that books scoring high along one dimension tended to score high along others. There was wide variability in the overall quality of the books, but several factors emerged as predictors of book quality. The most highly rated books tended to be those having a cognitive behavioral perspective, those written by mental health professionals, those written by authors holding a doctoral degree, and those focusing on specific problems. Implications of the findings, including specific recommendations for authors and consumers of self-help books, are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
106.
Turner Nigel A.; Gaskin Duncan J. H.; Yagnik Asutosh T.; Littlechild Jennifer A.; Vulfson Evgeny N. 《Protein engineering, design & selection : PEDS》2001,14(4):269-278
Enantioselectivity of enzyme catalysis is often rationalizedvia active site models. These models are constructed on thebasis of comparing the enantiomeric excess of product observedin a series of reactions which are conducted with a range ofhomologous substrates, typically carrying various side chainsubstitutions. Surprisingly the practical application of thesesimple but informative `pocket size' models has been rarelytested in genetic engineering experiments. In this paper wereport the construction, purification and enantioselectivityof two recombinant Rhizomucor miehei lipases which were designedto check the validity of such a model in reactions of ring openingof oxazolin-5(4H)-ones. 相似文献
107.
108.
In this editorial, the new editor of Psychology of Addictive Behaviors discusses the journal's history, role, scope of content, review criteria, and goals. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
109.
110.
Two systems for measuring flour water absorption (WA), the farinograph (FAR) and the Wheat Research Institute, 125 g mechanical dough development (MDD) standard bake test system, were compared using a representative sample of 20 commercial flours. A highly significant correlation (r = 0.93) was found which yielded the predictive equation: WAMDD = 0.66 × WAFAR + 181 The 95% prediction limits for 125 g MDD water absorptions from this equation were ± 15 g kg?1. This degree of accuracy was largely due to excellent farinograph reproducibility. Other farinograph parameters (development time, stability and breakdown) were highly correlated with the work input required for 125 g mechanical dough development, but only development time was significantly correlated with the volume of loaves baked on the 125 g standard bake system. This lack of prediction of baking quality for the farinograph could partly be because it simulates bulk fermentation mixing, rather than the more intensive mixing of the mechanical dough development process used for the loaves in this experiment. However, the loaf volume range was diminished since sample preparation involved bulking flours by water absorption. 相似文献