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141.
In most studies using informant reports of personality, the informants are recruited by the targets. Such informants may tend to like the targets and thus portray them in specific ways (e.g., too positively). Study 1 (N = 403) demonstrated the necessity to distinguish between “liking” and “knowing” in studying the relationships between informants and targets. Informants who liked their targets better described them more positively (i.e., as being more extraverted, agreeable, open, conscientious, and less neurotic). The association between personality ratings and liking was moderated by item evaluativeness. Liked targets were also described as being more similar to each other (range restriction), which would lower correlations of informant ratings of personality with external variables. Study 2 (N = 90) used a within-subjects design to disentangle actual personality differences between targets (substance) from the informants’ specific views on the targets (style). Ninety informants were asked to nominate targets they did not like. These targets then nominated informants of their own choice. Target-nominated informants liked the targets very much and described the targets’ personalities very positively and in ways that were highly redundant with the average target’s self-rating. There was evidence that lower liking may be associated with better accuracy. Higher subjective levels of knowing were not associated with better interrater agreement but with a greater willingness to describe targets negatively. Implications for the field of recruiting are discussed. Where possible, the choice of informants and referees should be made independent of the targets’ preferences. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
142.
Characterization of the intrinsic physical and mechanical properties of precursor-derived ceramics (PDC) is hitherto hindered by the unavailability of suitable specimens with the representative material structure, homogeneity and of sufficient dimensions amenable to the characterization method. The experimental response is often significantly modified by the included porosity and possible pseudo-microstructures, introduced through the sample fabrication. This paper describes the fabrication of fully dense homogeneous precursor-derived Si–C–N ceramic specimens with material structures covering amorphous to nano-crystalline state using a casting technique, from a liquid polysilazane precursor. The three critical problems involved in the dense PDC processing, viz., (i) bubble formation, (ii) gas evolution induced bloating and cracking and (iii) transformation induced cracking are addressed through controlled cross-linking and thermolysis techniques. Structural characterization of the specimens is carried out using FT-IR, Raman, XRD and HRTEM. The changes in the material structure in the amorphous and phase segregated state are correlated to the material properties, through preliminary physical and mechanical characterization. 相似文献
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J Fritz D Anselmetti J Jarchow X Fernàndez-Busquets 《Canadian Metallurgical Quarterly》1997,119(2):165-171
An ovary implanted into the spleen of an ovariectomized rat develops into a luteinized tumor, growing in response to gonadotrophins. Previously, it was shown that in vivo Buserelin, a gonadotrophin-releasing hormone (GnRH) analog, inhibited tumor growth. To determine if GnRH had a direct effect on tumor cells, the presence of GnRH receptors as well as the endocrine effects of buserelin were studied on tumoral tissue. GnRH receptors were present in luteoma in similar concentrations and dissociation constant (Kd) to control estrous ovaries. In vivo treatment with buserelin did not modify luteoma GnRH receptors. In organ incubations, luteoma secreted significantly higher estradiol and lower progesterone than estrous ovaries; addition of buserelin did not modify steroid secretion. The same difference in basal steroid secretion between luteoma cells and luteal cells superovulated prepubertal ovaries was observed in cell cultures. Although luteinizing-hormone (LH)-stimulated progesterone in both kinds of cells, buserelin significantly inhibited LH-stimulated progesterone only in luteoma cells. These results describe clear differences in basal steroid secretion between tumoral and normal tissue. Furthermore, they show that luteoma possess GnRH receptors similar to those in normal ovarian tissue, and that GnRH analogs have endocrine effects on these cells. Therefore, a direct effect of buserelin on luteoma cells can be postulated. 相似文献
146.
Fritz Klocke Vladimir Bäcker Hagen Wegner Björn Feldhaus Hans-Uwe Baron Roland Hessert 《Production Engineering》2009,3(4-5):391-399
Highly stressed components of modern aircraft engines, like fan and compressor blades, have to satisfy stringent requirements regarding durability and reliability. The induction of compressive residual stresses and strain hardening in the surface layer of these components has proven as a very promising method to significantly increase their fatigue resistance. The required surface layer properties can be achieved by the roller burnishing process, which is characterised by high and deeply reaching compressive residual stresses, high strain hardening and excellent surface quality. In order to achieve a defined state of the surface layer, the determination of optimal process parameters for a given task still requires an elaborate experimental set-up and subsequent time-consuming and cost-extensive measurements. The development of well funded process knowledge about the correlation of the process parameters, the processed geometry and the surface layer state is the subject of this article. 相似文献
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JD Fritz I Danko SL Roberds KP Campbell JS Latendresse JA Wolff 《Canadian Metallurgical Quarterly》1995,37(6):693-700
The expression of full-length dystrophin and various dystrophin deletion mutants was monitored in mdx mouse muscle after intramuscular injection of dystrophin-encoding plasmid DNAs. Recombinant dystrophin proteins, including those lacking either the amino terminus, carboxyl terminus, or most of the central rod domain, showed localization to the plasma membrane. This suggests that there are multiple attachment sites for dystrophin to the plasma membrane. Only those constructs containing the carboxyl terminus were able to stabilize dystrophin-associated proteins (DAP) at the membrane, consistent with other studies that suggest that this domain is critical to DAP binding. Colocalization with DAP was not necessary for membrane localization of the various dystrophin molecules. However, stabilization and co-localization of the DAP did seem to be a prerequisite for expression and/or stabilization of mutant dystrophins beyond 1 wk and these same criteria seemed important for mitigating the histopathological consequences of dystrophin deficiency. 相似文献
150.
Simulation models are a practical tool for reengineering and redesigning processes and workflows, because they infuse management discussions with the quantitative data needed for sound decision making. The Government Printing Office's use of a discrete-event simulation model helps illustrate the tool's potential to increase revenue, improve customer service, and optimize resource utilization in the area of telephone ordering. 相似文献