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11.
UML在流程工业优化调度工艺描述系统中的应用   总被引:1,自引:0,他引:1  
结合建模工具Rational Rosc说明如何在系统开发过程中运用UML建模。通过流程工业优化调度工艺描述系统的实际建模,对UML建模应用作了进一步说明。  相似文献   
12.
线性最优调节器二阶工程设计法及应用   总被引:1,自引:0,他引:1       下载免费PDF全文
本文利用文[1]结论,给出一种实用线性最优调节器二阶工程设计法.该设计法建立了古典控制意义上的系统性能指标与二次型性能指标的关系.并给出解析其式,提出二阶最优参数域的概念.通过轧机综合最优控制系统的设计和实验,验证了该方法在工程设计中的可行性.  相似文献   
13.

Definition of the problem

“Medical necessity” (MedN) is the central regulatory concept for decisions about which services are covered by German statutory health insurance. Despite its seeming objectivity and dependence on physicians’ expert judgment, the concept is by no means clearly defined.

Arguments

In this first of five planned papers on the conceptual analysis of MedN from the perspectives of philosophy and ethics of medicine, law, and (social) medicine, the focus lies on systemizing ongoing controversies.

Conclusion

Our goal is to come up with a so far missing foundation for detailed debates. We aim to clarify MedN’s conceptual structure, function, contextuality, and ambiguities as well as the fundamental limits of conceptual investigations for the normative questions at issue of regulating medical services.
  相似文献   
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This paper presents the results of a survey of the livelihoods of people living in the eastern part of the subtropical plains of Nepal, known as the terai. Both qualitative and quantitative approaches were used in the survey and further data were obtained through focus group discussions, in-depth interviews with key informants and participant observations. Changes were recorded both in the perception of agricultural and residential land for a secure living and the meaning given to food security. The principal drivers causing these changes were voluntary out-migration for remunerative employment, urbanization and the reluctance of members of the younger generation to farm, which they regard as a “dirty job”. In consequence, people’s livelihood practices and access to food are gradually shifting from an agriculture-based economy to an economy that is based on other sources of income, including remittances from out-migrants. This development threatens not only the role of agriculture in rural livelihoods but also the food security of the country.  相似文献   
16.
Argon belongs to the group of noble gases, which are regarded as chemically inert. Astonishingly some of these gases exert biological properties and during the last decades more and more reports demonstrated neuroprotective and organoprotective effects. Recent studies predominately use in vivo or in vitro models for ischemic pathologies to investigate the effect of argon treatment. Promising data has been published concerning pathologies like cerebral ischemia, traumatic brain injury and hypoxic ischemic encephalopathy. However, models applied and administration of the therapeutic gas vary. Here we provide a systematic review to summarize the available data on argon’s neuro- and organoprotective effects and discuss its possible mechanism of action. We aim to provide a summary to allow further studies with a more homogeneous setting to investigate possible clinical applications of argon.  相似文献   
17.
The Al-rich part of the Fe-Al phase diagram between 50 and 80 at.% Al including the complex intermetallic phases Fe5Al8 (ε), FeAl2, Fe2Al5, and Fe4Al13 was re-investigated in detail. A series of 19 alloys was produced and heat-treated at temperatures in the range from 600 to 1100 °C for up to 5000 h. The obtained data were further complemented by results from a number of diffusion couples, which helped to determine the homogeneity ranges of the phases FeAl2, Fe2Al5, and Fe4Al13. All microstructures were inspected by scanning electron microscopy (SEM), and chemical compositions of the equilibrium phases as well as of the alloys were obtained by electron probe microanalysis (EPMA). Crystal structures and the variation of the lattice parameters were studied by x-ray diffraction (XRD) and differential thermal analysis (DTA) was applied to measure all types of transition temperatures. From these results, a revised version of the Al-rich part of the phase diagram was constructed.  相似文献   
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Drug‐resistant Pseudomonas aeruginosa (PA) strains are on the rise, making treatment with current antibiotics ineffective. Hence, circumventing resistance or restoring the activity of antibiotics by novel approaches is of high demand. Targeting the Pseudomonas quinolone signal quorum sensing (PQS‐QS) system is an intriguing strategy to abolish PA pathogenicity without affecting the viability of the pathogen. Herein we report the structure–activity relationships of 2‐sulfonylpyrimidines, which were previously identified as dual‐target inhibitors of the PQS receptor PqsR and the PQS synthase PqsD. The SAR elucidation was guided by a combined approach using ligand efficiency and ligand lipophilicity efficiency to select the most promising compounds. In addition, the most effective inhibitors were rationally modified by the guidance of QSAR using Hansch analyses. Finally, these inhibitors showed the capacity to decrease biofilm mass and extracellular DNA, which are important determinants for antibiotic resistance.  相似文献   
20.
The spray-drying behaviour of 16 water-miscible organic solvents on a bench-scale machine (Büchi B290 with inert loop) was determined under mild-to-moderate process conditions, namely inlet gas temperature of 130?°C and liquid feed flow rate of ≤3?mL/min. The solvents with boiling points below the inlet gas temperature could be fully dried (Group 1 solvents). The two exceptions were DMSO and DMF which despite their higher boiling points could be fully dried. The remaining solvents with boiling points above the inlet gas temperature were not fully dried during passage through the spray-dryer (Group 2 solvents). Trypsin and lysozyme when spray-dried from Group 1 solvent binary mixtures with water showed similar inactivation and residual water content, independent of solvent. The level of residual solvent was, however, strongly dependent on solvent. Trehalose (20%) and mannitol (10%) could be spray-dried from DMSO/water binary mixtures, but the amorphous disaccharide required higher inlet gas temperature. Trehalose/trypsin and mannitol/trypsin formulations showed differing degrees of protection against enzyme inactivation when spray-dried from Group 1 solvent binary mixtures with water. In all solvents the mannitol protected as well, if not better, than the trehalose. This study identifies some suitable organic solvents for spray-drying protein formulations, but also shows the difficulties of remaining organic solvent under the moderate inlet gas temperature used.  相似文献   
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