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971.
This study aims to extend the understanding of the window-opening control by occupants in private and two-person offices in summer. A field study was carried out from 13 June to 15 September 2006 in offices with and without night ventilation, located in Cambridge, UK. The monitoring data give evidence that there is a statistically significant relationship between window-opening behaviour patterns and indoor stimulus (i.e., indoor air temperature) in summer. The activity of window control in offices both with and without night ventilation was mostly constrained to the start of period of occupation. Once a window state had been set up on the arrival it mainly stayed the same until departure. The percentages of total window change events in offices without night ventilation during the intermittent period from open to closed and closed to open were 3% and 2%, respectively. A window in an office that featured a night cooling strategy was always open upon the departure whenever the room temperature was over 23.6 °C. Finally, the stochastic models to predict window-opening behaviour patterns as a function of indoor temperature, time of day and the previous window state were developed. 相似文献
972.
Olivier Vauquelin 《Tunnelling and Underground Space Technology incorporating Trenchless Technology Research》2008,23(2):171-178
When a fire occurs in a long tunnel, smoke control is crucial for obvious reasons of safety. Ventilation and extraction systems have to be designed with accuracy in order to control the longitudinal motion of the fire-induced smoke and to extract it efficiently in a zone close to the fire source. This paper presents experimental investigations carried out on a small scale tunnel model (scale reduction is 1:20) to study the fire-induced smoke control by longitudinal and transverse ventilation systems. The experimental model is non-thermal and a buoyant release (a mixing of air and helium) is used to represent the fire smoke plume. The main objective of this model is to represent, as well as make possible, the duality between inertial forces (due to ventilation) and buoyant forces. Radiation and heat losses at the walls are not taken into account in this model. At first, the principle of the simulation is widely described. Then, some results are presented for both longitudinal and transverse smoke control by a mechanical ventilation. Finally, perspectives for future investigations are proposed. 相似文献
973.
针对目前国内地铁站台、隧道设置的通风和排烟设施的情况,分析了地铁站台、隧道的通风和排烟存在的问题,并提出了整改措施,指出科学设置防排烟设施以及事故状态下合理进行防排烟处置,对于减少人员伤亡和财产损失具有重要意义。 相似文献
974.
高瓦斯隧道施工通风设计 总被引:1,自引:0,他引:1
通过云顶高瓦斯隧道施工通风,详细介绍了瓦斯隧道通风方案、通风计算、风机的选型,以完善高瓦斯隧道的通风设计,保证高瓦斯隧道的施工安全,对类似瓦斯隧道施工通风具有借鉴作用。 相似文献
975.
结合工程概况,从通风排烟的设计原则、通风排烟的布置形式、通风机的造型等方面介绍了长大隧道独头通风排烟设计和管理应注意的问题,并对工作面的风量及通风机全压进行了具体计算,从而保证了长大隧道施工人员的身心健康。 相似文献
976.
Ian S. Lowndes Amanda J. Crossley Zhi-Yuan Yang 《Tunnelling and Underground Space Technology incorporating Trenchless Technology Research》2004,19(2):139
The extraction of minerals and coal at greater depth, employing higher-powered machinery to increase production levels has imposed an increased burden on ventilation systems to maintain an acceptable working environment. A deterioration in the climate experienced within these workings may also adversely affect the health and safety of the workforce. In the UK, mineral extraction is now being practiced at depths of over 1000 m. In addition, the adoption of continuous miner and tunnel bolting support methods has permitted improved development rates to be achieved at the cost of increased emissions of dust, gas and heat and humidity. There is a recognized need to improve the efficiency in the design and operation of auxiliary ventilation systems to maintain an adequate underground environment and climate. Any improvement achieved in the quality, quantity and control of the delivered ventilation will assist in the provision of improved gas and dust dilution and climatic control. Due to the constraints imposed by the mining method, there may be an economic or practical limit to the climatic improvement that may be obtained by the sole use of ventilation air. Where this limit is identified, there may be the need to consider the selective application of air-cooling systems. The paper details the construction of a computer based climatic prediction tool developed at the University of Nottingham. This work builds upon earlier research (Ross et al., 1997, Proceedings of 6th International Mine Ventilation Congress, SME, Littleton, CO, pp. 283–288) that developed a prototype model for short tunnel developments. The current model predicts the psychrometric and thermodynamic conditions within long rapid development single entry tunnel drivages. The model takes into account the mass and heat transfer between the strata, water, machinery and the ventilation air. The results produced by the model have been correlated against ventilation, climatic and operational data, obtained from a number of rapid tunnel developments within UK deep coalmines. The paper details the results of a series of correlation and validation studies conducted against the ventilation and climate survey data measured within 105s district Tail Gate tunnel development at Maltby Colliery, UK. The paper concludes by presenting the results of a case study that illustrate the application of the validated model to the design and operation of an integrated mine ventilation and cooling system. The case study illustrates the effect that an increased depth and hence increased virgin strata temperature has on the climate experienced within rapid tunnel developments. Further investigations were performed to identify the optimum cooling strategy that should be adopted to maintain a satisfactory climate at the head of the drivage. 相似文献
977.
柴油发电机房的设计及安装应注意的几点问题 总被引:2,自引:0,他引:2
本文通过分析柴油发电机房环境温度对柴油机出力产生的影响以及机房在设计、安装过程中存在问题的探讨,阐明机房选址、机房通风排气对柴油发电机效率的重要性。 相似文献
978.
多病床非典病房的气流分布研究 总被引:2,自引:0,他引:2
到2003年8月7日止,在全球34个国家和地区相继出现了严重急性呼吸系统综合症(SARS或者非典),其中,共报告有8422例疑似案例,916例死亡案例。2002年11月到2003年6月间的非典流行中,医院医护人员受感染情况最为严重,世界范围内20%的感染群体为医护人员,香港地区22%的确诊案例为医护人员。因此,为减少交叉感染,加强有关工程控制,特别是在非典病房里进行通风设计是非常必要的。本文总结了非典病房气流分布的最新研究。这项研究由非典特工队于2003年4~7月间完成。非典特工队是由香港工程师协会组织,来自7个专家协会的工程师组成的研究小组。在对香港治疗非典医院的现有空调系统进行了解后,非典特工队首先运用计算流体力学模拟确定了在6个床位的病房里减少交叉感染和改善污染物稀释的通风设计;接着,对新设计在香港大学屋宇设备实验室里的全尺寸非典病房里进行了测试。测试表明,新设计方案在这个接近现实的全尺寸非典病房里运行良好。采用床头回风口回风设计可有效地对病人产生的含病毒颗粒进行局部捕获。根据这项研究,作者提出了原则性的设计建议。2003年里,香港政府和医院管理局医院采纳了非典特工队提出的设计基本原理建造了1200多个床位的可用于非典治疗的新病房。另外,气流分布是复杂的紊流过程,送风格栅结构如导流器或散流器的微小改动以及送风参数如风速、温度和风向的微小变化都会引起气流的改变。适当的设计对于减少病人间、病人与医护人员之间的交叉感染以及有效稀释和排除含病菌颗粒都是至关重要的。 相似文献
979.
单巷长距离掘进通风工艺研究 总被引:1,自引:0,他引:1
以康家滩煤矿首个单巷掘进工作面为依托,在考虑一般通风网络影响因素的基础上,探讨了在单巷长距离掘进工程中面临的通风问题,并首次将信号控制系统引进到单个掘进工作面,实现了工作面安全管理自动化,研究结果为康家滩矿88301工作面的顺利接续和安全生产奠定了坚实的基础,亦可供隧道及其他井项工程借鉴。 相似文献
980.