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排序方式: 共有985条查询结果,搜索用时 15 毫秒
1.
云浮电厂125 MW发电机组的闭式循环冷却水系统主要由冷却水塔、循环水泵和凝汽器等设备组成。经过多年生产运行,机组真空偏低。针对问题原因进行分析,介绍了通过对循环冷却水系统的改造来解决这一问题。 相似文献
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砌体结构房屋抗震加固评述 总被引:2,自引:0,他引:2
福建省地处台湾海峡西岸,位于东南沿海地震带上。省内有大量早期建造的砌体结构房屋抗震设防不足,进行抗震加固十分必要。本文评述了砌体房屋抗震加固措施及其新进展,并建议基于投资-效益准则选择抗震加固措施,以满足功能、安全及经济方面等要求。 相似文献
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Magdalena Baborska-Narożny Fionn Stevenson Magdalena Grudzińska 《Building Research & Information》2017,45(1-2):40-59
ABSTRACTThe overheating risk in flats (apartments) retrofitted to energy-efficient standards has been identified by previous studies as one that is particularly high. With climate change and rising mean temperatures this is a growing concern. There is a need to understand the kinds of practices, learning and interventions adopted by the occupants of individual homes to try to reduce overheating, as this area is poorly understood and under-researched. This case study focuses on the impact of different home-use practices in relation to the severity of overheating in 18 flats in one tower block in northern England. Internal temperatures monitored in comparable flats show that the percentage of time spent above the expected category II threshold of thermal comfort according to BS EN 15251 can differ by over 70%. Extensive monitoring, covering a full year, including two summer periods, has identified emergent changes in heatwave practices linked with increased home-use skills and understanding among the research participants. Close analysis of design intentions versus reality has identified key physical barriers and social learning opportunities for appropriate adaptation in relation to heatwaves. Recommendations for designers and policy-makers are highlighted in relation to these factors. 相似文献
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Jennifer M. Logue Iain S. Walker Brett C. Singer 《Journal of Building Performance Simulation》2016,9(1):1-16
Changing the air exchange rate of a home affects the annual thermal conditioning energy. Large-scale changes to air exchange rates of the housing stock can significantly alter the residential sector's energy consumption. However, the complexity of existing residential energy models is a barrier to the accurate quantification of the impact of policy changes on a state or national level. The Incremental Ventilation Energy (IVE) model introduced here combines the output of simple air exchange models with a limited set of housing characteristics to estimate the associated change in energy demand of homes. The IVE model was designed specifically to enable modellers to use existing databases of housing characteristics to determine the impact of ventilation policy change on a population scale. The IVE model estimates of energy change when applied to US homes with limited parameterization are shown to be comparable to the estimates of a well-validated, complex residential energy model. 相似文献
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为了分析1000 MW机组空预器防堵灰改造项目的技术经济性,以某厂1000 MW机组为对象,比较了三种空预器防堵灰技术的优缺点,为了彻底解决堵灰问题选择了风量分切防堵灰技术,风量分切技术是首次在东方锅炉1000 MW机组上应用,此改造项目投资640万元,每年可节约成本437万元,通过静态投资回收期法分析,约1.5年就可以收回投资,项目可行。 相似文献
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为研究扇形铅黏弹性阻尼器与加固框架结构之间的匹配关系及其对加固框架抗震性能的影响规律,用ABAQUS软件建立了对比空框架和加固框架的精细化有限元模型,结合试验试件骨架曲线及破坏形态验证了其合理性。提出扇形铅黏弹性阻尼器加固框架的综合设计原则,设定阻尼器扇形有效半径与框架柱净高之比为设计尺寸比,在此基础上,对不同设计尺寸比的加固框架进行对比分析。分析结果表明,合理设置的扇形铅黏弹性阻尼器可以显著提高加固框架的抗震性能,保护梁柱节点核心区;当设计尺寸比取值超过0.24时,会导致加固试件较早达到峰值荷载,但其后承载力又急剧衰减;建议扇形铅黏弹性阻尼器加固框架的设计尺寸比宜控制在0.1~0.2之间,实际设计中应依据不同加固需求选取相应的设计尺寸比。 相似文献
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Gary Pivo 《Building Research & Information》2014,42(5):551-573
The energy efficiency of US multifamily rental housing is compared with other housing types. A real and growing energy efficiency gap is documented, particularly for lower income households. Findings are based on data from the 2005 and 2009 US Residential Energy Consumption Survey (RECS). Individual energy efficiency features related to HVAC (heating, ventilation and cooling) systems, appliances, and the building envelope are analysed along with weighted and unweighted total energy efficiency indices. Multifamily units occupied by low income renters had 4.1 fewer energy efficiency features in 2005 and 4.7 fewer in 2009 compared with other households. If the number of efficiency features was on par with other housing, the savings could be in the range of US$200–400 per year for most lower-income renters in multifamily buildings. There is an astonishing lack of information on how efficiency retrofits would affect property (real estate) metrics such as cash flow and value. Available evidence suggests that millions of US properties could be good retrofit investment opportunities. Better efficiency would allow renters to increase spending on food, healthcare and other essentials. This is not only an economic issue: it has implications for household health, social equity and environmental problems tied to energy consumption. 相似文献