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101.
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M. Taroni C. J. W. Breward P. D. Howell J. M. Oliver R. J. S. Young 《Journal of Engineering Mathematics》2012,73(1):93-119
We present a two-dimensional large-aspect-ratio model for the off-contact screen printing of a power-law fluid. We extend
the work of White et al. (J Eng Math 54:49–70, 2005) by explicitly including the fluid/air free surface that is present beneath the screen ahead of the squeegee. In the distinguished
parameter limit of greatest interest to industry, the process is quasi-steady on the time-scale of a print and can be analysed
in three separate regions using the method of matched asymptotic expansions. This allows us to predict where the fluid transfers
through the screen, the point at which it first makes contact with the substrate, and the amount of fluid deposited on the
substrate during a print stroke. Finally, we show that using a shear-thinning fluid will decrease the amount of fluid transferred
ahead of the squeegee, but increase the amount of fluid deposited on the substrate. 相似文献
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Histology is the gold standard for confirming thermally induced necrosis. Generally, however, no specimen is obtained from thermal ablation therapy for pathological examination. The aim of this study was to provide evidence for the relationship between temperatures reached and resulting tissue coagulation during laser ablation in a near-physiological ex vivo lung tumor model by combining viability staining and direct temperature measurement. 相似文献106.
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Srivastava Sanjay; Tamir Maya; McGonigal Kelly M.; John Oliver P.; Gross James J. 《Canadian Metallurgical Quarterly》2009,96(4):883
There is growing interest in understanding how emotion regulation affects adaptation. The present study examined expressive suppression (which involves inhibiting the overt expression of emotion) and how it affects a critical domain of adaptation, social functioning. This investigation focused on the transition to college, a time that presents a variety of emotional and social challenges. Analyses focused on 2 components of suppression: a stable component, representing individual differences expressed both before and after the transition, and a dynamic component, representing variance specific to the new college context. Both components of suppression predicted lower social support, less closeness to others, and lower social satisfaction. These findings were robustly corroborated across weekly experience reports, self-reports, and peer reports and are consistent with a theoretical framework that defines emotion regulation as a dynamic process shaped by both stable person factors and environmental demands. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Ross D. King Maria Liakata Chuan Lu Stephen G. Oliver Larisa N. Soldatova 《Journal of the Royal Society Interface》2011,8(63):1440-1448
The reuse of scientific knowledge obtained from one investigation in another investigation is basic to the advance of science. Scientific investigations should therefore be recorded in ways that promote the reuse of the knowledge they generate. The use of logical formalisms to describe scientific knowledge has potential advantages in facilitating such reuse. Here, we propose a formal framework for using logical formalisms to promote reuse. We demonstrate the utility of this framework by using it in a worked example from biology: demonstrating cycles of investigation formalization [F] and reuse [R] to generate new knowledge. We first used logic to formally describe a Robot scientist investigation into yeast (Saccharomyces cerevisiae) functional genomics [f1]. With Robot scientists, unlike human scientists, the production of comprehensive metadata about their investigations is a natural by-product of the way they work. We then demonstrated how this formalism enabled the reuse of the research in investigating yeast phenotypes [r1 = R(f1)]. This investigation found that the removal of non-essential enzymes generally resulted in enhanced growth. The phenotype investigation was then formally described using the same logical formalism as the functional genomics investigation [f2 = F(r1)]. We then demonstrated how this formalism enabled the reuse of the phenotype investigation to investigate yeast systems-biology modelling [r2 = R(f2)]. This investigation found that yeast flux-balance analysis models fail to predict the observed changes in growth. Finally, the systems biology investigation was formalized for reuse in future investigations [f3 = F(r2)]. These cycles of reuse are a model for the general reuse of scientific knowledge. 相似文献
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Measurement of Helium Leakage Rates through Closures of Dangerous Goods Packagings for the Assessment of Potentially Explosive Mixtures in Freight Containers 下载免费PDF全文
Eva Schlick‐Hasper Oliver Seidler Thomas Goedecke Matthias Kraume 《Packaging Technology and Science》2015,28(11):959-985
The objective was to find out whether an explosive atmosphere can be created in a freight container by gaseous leakage flow of vapour‐air‐mixture through leaks in the closures of dangerous goods packagings filled with hazardous liquids. Because of high temperatures during intercontinental carriage, there is a gauge pressure in the free vapour phase inside the packagings which can cause a gaseous leakage flow. Two different methods were applied: Helium limit leakage rates for 23 quantitatively important hazardous liquids concerning their lower explosion limit (LEL) were calculated for a worst case transport scenario (Method 1). Helium leakage rates of five closure types of dangerous goods packagings with volumes of approximately 6 l were measured using the pressure technique by accumulation (Method 2). All types of closures of steel packagings were uncritical. The maximum measured leakage was 33% of the limit leakage rate. The leakage rates of screw closures of plastic jerricans can exceed the LEL if there are production‐related patterns such as non‐concentricity of the closures and flashes on the neck. Especially for plastic packagings it is important to minimize gaseous leakage flow, because an explosive atmosphere can also be reached by permeation of the individual filling substance or by a combination of both effects. For the assessment of potentially explosive mixtures in freight containers, both mass transfer mechanisms have to be taken into account. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献