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651.
公众聚集场所火灾疏散性能化分析方法研究 总被引:1,自引:1,他引:0
张云明 《中国安全生产科学技术》2011,7(10):70-74
针对公众聚集场所人员密集的特点和现行规范适用上的局限性问题,本文就公众聚集场所火灾条件下的人员疏散性能化分析方法进行研究,构建了以安全疏散为主线的性能化分析技术体系,确定了保障人员生命安全的总体目标和人员安全疏散的性能指标可接受阈值。通过火灾场景设计和烟气蔓延模型的运用,归纳总结可用疏散时间的计算模型;通过分析现有疏散需要时间计算模型的不足,提出利用当量疏散速度解决疏散模型中火灾对疏散过程影响的问题。研究结果对建筑火灾疏散安全性分析具有重要的指导意义,为我国的安全疏散性能化分析方法体系的建立和应用提供参考。 相似文献
652.
基于集对分析法的建筑物火灾危险性评价 总被引:1,自引:1,他引:0
建筑物是一个集人员与财产于一体的系统,一旦发生火灾,后果不堪设想。介绍了集对分析的基本理论,并将其引入建筑物火灾危险性评价中。在不考虑系统指标权重与考虑系统指标权重条件下,讨论了建筑物火灾危险性评价步骤。同时,将建筑物火灾危险性的评价结果与集对势相结合来判断建筑物火灾危险性态势。结果表明,某建筑物在不考虑指标权重与考虑指标权重两种条件下均处于“一般安全”等级,但后者的安全等级程度更低,两种情况的态势均属于微同势,也说明了该建筑物需要进一步采取安全措施,加强安全管理,提高其安全程度,从而避免火灾事故的发生。 相似文献
653.
高层建筑火灾时,正压防烟带入的大量新鲜空气被送入着火层并稀释了烟气,降低了机械排烟效率.提出设置高层建筑条形走廊-前室缓冲区的设想,采用双方程κ-ε模型,对设置缓冲区后排烟效果的影响进行了模拟和分析.结果表明:建有前室缓冲区后,前室内烟气的平均质量分数远小于4.6%,前室在较长时间内处于安全状态.从走廊扩散至竖井的烟气分别经过走廊、前室两次降温,温度下降明显,在竖井中容易形成滞止状态,使其向上方其他楼层扩散的趋势降低,对整栋楼内人员疏散而言更为有利. 相似文献
654.
对长沙市冬季某商场建筑室内餐饮区、化妆品区、鞋包区、服饰区和室外同步进行了细颗粒物(PM2.5)质量浓度的实测.分析了室内不同功能区、室外PM2.5质量浓度随时间的变化特征,并分析了温度、相对湿度、风速、大气压力对PM2.5质量浓度的影响.结果表明:室外PM2.5质量浓度高于室内;室内餐饮区PM2.5质量浓度最高,其次是化妆品区和服装区,鞋包区最低;室内人为活动和室外污染共同影响着室内颗粒物质量浓度;风速与PM2.5质量浓度相关性较弱,温度、相对湿度、大气压力与PM2.5质量浓度具有较强的相关性. 相似文献
655.
本文以某学院6号楼为例,研究标识设置对教学楼通道疏散能力影响,测定了不同标识设置情况楼道人流时程,结果表明:自然状态人流速峰值66.8人/min,持时2.823min,拥堵明显;立体标识使人流速峰值提升3%,使峰值持时缩短51.65%,墙面平铺张贴标识使人流速峰值提升1%,使持时缩短44.07%,立体标识优于墙面平铺张贴标识;早期疏导标识使人流速峰值提升6%,使持时缩短60.93%,使峰值出现时刻比自然状态提前约31%,疏散效果明显。同时本文分析了现有标识设置的问题和弊端。 相似文献
656.
Material selection in manufacturing may be characterized as a series of trade-offs between characteristics, properties, environmental impacts, sustainability, availability, and economics. Societal concerns about the environmental impacts of construction practices and materials have been expressed through an increase in the demand, production and use of “green” building products. This, combined with a desire to integrate more bioproducts and natural and renewable resources into the construction industry, has extended to the production and promotion of insulation made from sheep's wool.Although substantial literature exists on the insulation properties and other benefits of wool, less is known about the economics and manufacturing processes of sheep's wool insulation at varying scales of production. This paper contributes to this field of enquiry through presentation of the preliminary results of a wool insulation manufacturing pilot project, in which the scale and economics of the production of sheep's wool insulation were considered. Processing techniques, the impact of sheep breed, yield, energy use, and manufacturing costs were also examined. The results of the pilot project indicate that, while sheep's wool insulation produced at a smaller, or artisanal scale shows some potential, scale of operation and volume of production need to be carefully considered in order to ensure long-term sustainability of the operation. Using the least expensive sheep's wool available for the manufacture of wool batt insulation (and thereby reducing production costs) did not, in this pilot study, have a negative impact on productivity or product performance. Diversion of this waste stream of currently less marketable, and consequently less valuable wool, into the production of a green building material may offer small but significant benefit to sheep producers and the broader agricultural community, as well as consumers. 相似文献
657.
秸秆收贮利用体系建设的困境与政策建议 总被引:2,自引:0,他引:2
我国拥有丰富的秸秆资源,但秸秆资源的利用效率很低,主要原因是秸秆收贮利用体系建设严重滞后。加强秸秆收贮利用体系建设,应强化政府对秸秆收贮利用体系建设的规范和引导,整合秸秆收贮利用各环节的相关资源,并拓宽秸秆利用企业的融资渠道。 相似文献
658.
《International Journal of Green Energy》2013,10(1):65-77
Abstract Heating and air-conditioning systems have very low exergetic efficiency as they dissipate primary energy resources at low temperatures usually between 90 and 60°C. This compounds the problem that buildings spend approximately 30% of all the energy consumed in the U.S. for heating and air-conditioning. The overall result is a large entropy production and long-term environmental degradation that can be resolved only by substituting primary energy resources by low-temperature, waste, or alternative energy resources, usually available below 50°C. For such a replacement to be feasible the environmental cost of exergy production must be factored into calculations and compatible HVAC systems must be developed without any need for temperature peaking or equipment oversizing. This article addresses environmental and often-conflicting problems associated with exergy production by HVAC systems and presents an analytical optimization and control algorithm. Results indicate that when a careful design optimization is accompanied by a dynamic control of the split between radiant and convective means of satisfying thermal HVAC loads, exergy efficient sustainable buildings may be cost effective and environmentally benign. 相似文献
659.
针对传统疏散方式很难在短时间内有效地将人员疏散至室外安全区的难题,研究分析了超高层建筑中人员疏散策略以及电梯作为辅助人员疏散方式的可行性。首先,对人员疏散速度进行了研究,对电梯运行特性进行了分析;然后,利用数值模拟的方法,对影响电梯辅助疏散的参数进行研究,以对超高层建筑人员疏散以及疏散电梯的设计提供理论参考。结果表明,电梯与疏散楼梯相结合的疏散方式能够快速地完成高层建筑内部人员疏散。该组合疏散方式中决定总疏散时间的主要因素是疏散人数、电梯运行速度、电梯容纳人数、电梯疏散人员比例。当电梯疏散人数占总体疏散人数的40%时,疏散总时间最短。 相似文献
660.
Besides energy conservation, theexploration of renewable energy sources, inparticular biomass and solar energy, arecentral aspects of the Austrian energypolicy, regarded as an optimal option forachieving CO2-emission reductionobjectives.The market penetration of RenewableEnergy Technologies in the last twentyyears was supported by the AustrianEnergy Research Programme. The result ofsuccessful developments of biomass heating,solar thermal, solar electrical and windenergy technologies is the key for themarket development of these renewableenergy technologies.With the market penetration of renewableenergy technologies new business areas wereestablished and employment created.Today, some renewable energy technologiesin Austria have reached economiccompetitiveness. Some technologies notreached commercialisation, and need moredevelopment to improve efficiency,reliability and cost to become commercial.This would include material and systemdevelopment, pilot plants or fieldexperiments to clarify technical problems,and demonstration plants to illustrateperformance capabilities and to clarifyproblems for commercialisation. 相似文献