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21.
Srinivas Ravindra Babu Behara Paul Kippax Ian Larson David A.V. Morton Peter Stewart 《Chemical engineering science》2011,(21):72
The purpose of this study was to understand the kinetics of emptying of micronised salbutamol sulphate (SS) and lactohale 300 (LH300) under varying air flow rates (30–180 L min−1) from three dry powder inhaler devices, Rotahaler® (RH), Monodose Inhaler® (MI) and Handihaler® (HH). Aerosol concentration vs. time profiles, determined through real-time laser diffraction particle sizing, demonstrated that the majority of the powder from RH was emitted within one second while a more prolonged aerosolisation was observed from MI and HH. Peak aerosol concentrations were achieved more rapidly from RH compared to MI for both SS and LH300. Calculated cumulative emitted mass (CCEM) vs. time profiles were obtained from the aerosol concentration vs. time profiles and the emitted mass and the rate of CCEM (kCCEM), estimated from a modelling approach, increased with increasing air flow rates. The kCCEMvs. air flow rate profiles of SS and LH300 were significantly different at high air flow rates. The kCCEM was highest from RH and lowest from MI. Differences in kCCEM between the devices were related to capsule aperture size while the differences between the materials were due to the powder bed structure. This approach provided an understanding of the rate at which powder mass emptied from dry powder inhaler devices and was proposed to be a powerful development tool for the future powder inhalers. 相似文献
22.
《Building Research & Information》2013,41(3):190-195
The Green Building Materials '96 (GBM '96) conference brought manufacturers of building materials and products into the process of defining what may be called ‘green building materials’. Forty-seven manufacturers and associations presented information on environmental and associated quality criteria of their products. In addition, materials analysis and certification, building design, implementation, information sources and marketing were discussed. Charles J. Kibert and Gisela Bosch report. 相似文献
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马正纲 《昆明理工大学学报(自然科学版)》1988,(1)
本文提出一种新型联轴器“尼龙绳缠绕式联轴器”的结构尺寸方案,共分L1~L10种,这种联轴器由于采用了尼龙绳这种挠性构件,和其它联轴器相比,除保持了它们的一些优点外,特别能在较大范围内补偿角度位移和径向位移,还能承受较大的冲击载荷;制造容易,装配、维护、更换方便,结构简单,适应性强;和同尺寸的弹性圈柱销联轴器相比其许用扭矩还大些,而零件则少了许多;经试用,效果良好,有很好的经济效益。 相似文献
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Youji Fukada 《Pattern recognition》1980,12(6):395-403
This paper describes two clustering procedures for region analysis of image data and discusses the security of these algorithms theoretically. First our algorithms find kernels of regions and then classify pixels into regions using these kernels. The first algorithm distinguishes the regions that have far more distances than the given distance and the second algorithm distinguishes C regions that are great distances from each other in the feature space. These parameters are criteria which decide whether regions are similar or dissimilar. Examples are presented in order to show how these algorithms work for real image data. 相似文献
26.
采取问卷调查方式,对江苏省内职业性放射性疾病诊断医师、放射工作人员、放射卫生监督人员开展问卷调查,评估5项常见职业性放射性疾病诊断标准在江苏省的实施情况。结果表明:(1)职业性放射性疾病诊断医师对标准的掌握率为61%~89.6%;参加培训率为59.7%~92.2%;标准应用率为62.3%~68.8%,其培训率和应用率显著高于放射卫生监督人员。(2)放射工作人员除《职业性放射性皮肤疾病诊断》的知晓率同放射卫生监督人员有明显差别外,其余标准知晓率两者无统计学差异。(3)放射卫生监督人员标准的培训率为3.2%~48.0%,显著低于职业性放射性疾病诊断医师和放射工作人员,差异有统计学意义。(4)放射工作人员对职业性放射性疾病认知情况的问题回答正确率为34.7%~89.7%,且医疗机构和非医疗机构无明显差别,放射工作人员对申请职业性放射性疾病提交材料的认知情况为73.6%~100%。(5)职业性放射性疾病诊断医师、放射工作人员、放射卫生监督人员对标准中部分条款的认可度尚可。 相似文献
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V. Buytaert B. Muys N. Devriendt L. Pelkmans J.G. Kretzschmar R. Samson 《Renewable & Sustainable Energy Reviews》2011,15(8):3918-3933
Biomass is expected to play an increasingly significant role in the ‘greening’ of energy supply. Nevertheless, concerns are rising about the sustainability of large-scale energy crop production. Impacts must be assessed carefully before deciding whether and how this industry should be developed, and what technologies, policies and investment strategies should be pursued. There is need for a comprehensive and reliable sustainability assessment tool to evaluate the environmental, social and economic performance of biomass energy production. This paper paves the way for such a tool by analysing and comparing the performance and applicability of a selection of existing tools that are potentially useful for sustainability assessment of bioenergy systems. The selected tools are: Criteria And Indicators (C&I), Life Cycle Assessment (LCA), Environmental Impact Assessment (EIA), Cost Benefit Analysis (CBA), Exergy Analysis (EA) and System Perturbation Analysis (SPA). To evaluate the tools, a framework was constructed that consists of four evaluation levels: sustainability issues, tool attributes, model structure, area of application. The tools were then evaluated using literature data and with the help of a Delphi panel of experts. Finally, a statistical analysis was performed on the resulting data matrix to detect significant differences between tools. It becomes clear that none of the selected tools is able to perform a comprehensive sustainability assessment of bioenergy systems. Every tool has its particular advantages and disadvantages, which means that trade-offs are inevitable and a balance must be found between scientific accuracy and pragmatic decision making. A good definition of the assessment objective is therefore crucial. It seems an interesting option to create a toolbox that combines procedural parts of C&I and EIA, supplemented with calculation algorithms of LCA and CBA for respectively environmental and economic sustainability indicators. Nevertheless, this would require a more comprehensive interdisciplinary approach to align the different tool characteristics and focuses. 相似文献
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