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901.
Effective use of materials is one possible component of a sustainable manufacturing strategy. There are many such strategies proposed in the literature and used in practice, with confusion over what they are, what the differences among them may be and how they can be used by practitioners in design and manufacture to improve the sustainability of their product and processes. This paper reviews the literature on sustainable manufacturing strategies that deliver improved material performance. Four primary strategies were found: waste minimisation; material efficiency; resource efficiency; and eco‐efficiency. The literature was analysed to determine the key characteristics of these sustainable manufacturing strategies and 17 characteristics were found. The four strategies were then compared and contrasted against all the characteristics. While current literature often uses these strategy titles in a confusing, occasionally inter‐changeable manner, this study attempts to create clear separation between them. Definition, scope and practicality of measurement are shown to be key characteristics that impact upon the ability of manufacturing companies to make effective use of the proposed strategy. It is observed that the most actionable strategies may not include all of the dimensions of interest to a manufacturer wishing to become more sustainable, creating a dilemma between ease of implementation and breadth of impact.  相似文献   
902.
ABSTRACT

This paper quantifies construction and demolition waste (C&DW) generation rate in Indian cities using bottom-up material flow analysis approach. A dynamic model was applied to different classes of cities in India to investigate how C&DW generation rate varies across different classes of cities. The data on construction and demolition activities in different classes of cities were estimated from information reported in secondary literature. The results show that urban areas in India generated over 150 million tonnes of C&DW in 2016, and almost 50% of waste was generated in small to medium towns. The paper concludes with discussion on opportunities for recycling of C&DW and closing the material loops in Indian cities.  相似文献   
903.
为探明当前浙江省汽摩配行业挥发性有机物的整体排放与治理情况,以2015年浙江省范围内的70家汽摩配企业的VOCs调查数据为基础,展开了前期研究工作.通过分析全部70家汽摩配企业的调查数据,了解了行业的VOCs污染治理现状;通过深入研究筛选出的56家典型企业的调查数据,探究了行业的VOCs污染基本特征、以及初步计算了其VOCs排放系数.结果表明,虽然省内约三分之二的企业配有废气收集处理设施,但多数设施在运行维护方面存在着一定的问题;行业内使用的原辅材料以溶剂型为主,废气中VOCs的主要污染因子为二甲苯、乙酸丁酯、环己酮、乙酸乙酯、甲苯等物质;全省汽摩配行业的VOCs排放系数均值为4.14 kg·(万元)~(-1),其中汽配企业为2.94 kg·(万元)~(-1),摩配及通用型配件企业为7.15kg·(万元)~(-1).  相似文献   
904.
受限空间内细水雾与火相互作用的实验研究   总被引:18,自引:6,他引:18  
细水雾灭火系统作为卤代烷系列灭火剂的替代产品之一,以其高效无毒、经济实用的优点,近年来在国际上研究得非常活跃。本文在受限空间内利用先进的材料热释放速率测量仪研究了细水雾与火的相互作用过程,并得到了以下结论:细水雾通过汽化吸热冷却燃料及氧化剂、体积膨胀隔氧以及吸收热辐射降低对燃料的热回馈等效应与火相互作用,达到控制和扑灭火灾的目的,在受限空间内汽化隔氧效应起着重要作用。  相似文献   
905.
以溶剂热法制备Fe_3O_4磁性粒子,通过改良的St?ber法在其上包覆Si O_2,并用3-氨丙基三乙氧基硅烷对表面进行氨基修饰,制得Si O_2-NH_2/Fe_3O_4磁性复合材料,并将其用于制药废水二级出水的吸附处理(吸附剂投加量1 g/L、吸附时间120 min)。表征结果显示:Si O_2-NH_2/Fe_3O_4为粒径(510.0±3.6)nm的球形粒子。实验结果表明:在废水p H为5时,Si O_2-NH_2/Fe_3O_4对TOC、蛋白质、腐殖酸的吸附效果最佳,三者的去除率分别达44.14%,35.58%,33.07%,与Fe_3O_4相比分别提高了25.27,21.76,21.05百分点;废水p H为6时,Si O_2-NH_2/Fe_3O_4对多糖和色度的去除效果最佳,二者的去除率分别达26.03%和62.94%,与Fe_3O_4的最高去除率(p H=5时)相比分别提高了17.84百分点和22.45百分点;Si O_2-NH_2/Fe_3O_4重复使用4次,TOC和色度去除率均达初次使用时的87%以上。  相似文献   
906.
Zinc is one of the most widely applied nonferrous metals in China. Study on the applications and recurrent situation of zinc resources is of great strategic importance for the sustainable development of China's economy. In this paper, a dynamic material flow analysis (MFA) method has been adopted to analyze quantificationally zinc resources in China, as well as to analyze and predict the quantity of zinc product scrap and their recycling situation. The weighted average method was applied to calculate average lifetimes of six major zinc products in China. The average lifetimes of battery, zinc oxide, zinc die-casting alloys, zinc material products, galvanized zinc and brass are 0.17, 5.3, 11.1, 12, 21 and 30 years, respectively. Assuming the lifetime of zinc product group obeys the Weibull distribution and the consumption of zinc products varies linearly with time, the future consumption and scrap generation of zinc products will increase continuously. It is expected that they would increase from 49% to 76% during 2004–2020, respectively. Assuming the recycling rate remains unchanged with time, the zinc old scrap index, both the theoretical and actual values, would continue increasing in China. The values are expected to reach 0.402 and 0.076 by 2020, respectively. Therefore, the regeneration resource of depreciated zinc is actually insufficient in China. According to the scenario analysis, the actual value of old scrap indexes is positively correlated with the recycling rate of zinc products. Because galvanized products are the largest consumption area of zinc products in China, the influence of their recycling rate on old scrap index is obviously larger than other zinc products. Through the analysis, this paper suggests that the increase of the recycling rate of zinc products could not only improve to a certain degree China's relative shortage of zinc resources, but greatly relive the supply pressure of zinc in the world.  相似文献   
907.
袋式除尘行业里,所用滤料本身的性质有重要的意义,而衡量滤料性质的指标中最重要的一点就是其机械性能的稳定性。在产品大批量投产与使用之前,都要对这项指标进行测定。文章以PPS滤料为例,研究了在测定滤料机械性能时,样品选取尺寸的大小对其断裂强力和断裂伸长率两项机械性能测试数值的影响。  相似文献   
908.
This paper aims to contribute to the ongoing debate on the use of resource accounting tools in regional policy-making. The Northern Limits project applied material flow analysis (MFA) and ecological footprinting (EF) to regional policy-making in Northern Ireland over a number of years. The early phase of the research informed the regions first sustainable development strategy which was published in 2006 with key targets relating to the EF and improving the resource efficiency of the economy. Phase II identified the next steps required to address data availability and quality and the use of MFA and EF in providing a measurement and monitoring framework for the strategy and the development of the strategy implementation plan. The use of MFA and EF in sustainable regional policy-making and the monitoring of its implementation is an ongoing process which has raised a number of research issues which can inform the ongoing application and development of these and other resource accounting tools to within Northern Ireland, provide insights for their use in other regions, and help set out the priorities for research to support this important policy area.  相似文献   
909.
Residue materials generated in the metallurgical industry have gained an increasing importance, both from the points of view of energy and material supply. A joint process integration model for the integrated steel plant system is developed and used in this paper. It takes into account both residue materials and energy recirculation for the system. The potential for increased recirculation and the effect on the system from an environmental point of view is presented, and implementations and practical experiences are discussed. The model developed can serve as a benchmark for different steelmaking operations and constitute a basis for the continuous work involved in material, energy, environment or economic analyses for the steel production system.  相似文献   
910.
在调查研究的基础上 ,首先分析了皖东地区中药材资源的优势 ,建立了包括利用价值系数、利用现状系数、濒危系数、栽培系数、分布系数、蕴藏系数 6个评价指标的“中药材优先开发”指标体系 ,据此将皖东地区国家和省规定普查的 2 37种中药材确定为一级优先开发的有 6种、二级优先开发的有 79种、三级优先开发的有 96种、暂缓开发的有 5 6种。最后 ,以中药材资源的开发利用与保护为目的 ,将皖东地区划分为低山丘陵药材保护区、浅丘岗地药材开发区、沿湖河药材利用区以及沿淮洼地药材扩大区  相似文献   
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