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81.
82.
Gerzabek MH Barceló D Bellin A Rijnaarts HH Slob A Darmendrail D Fowler HJ Négrel P Frank E Grathwohl P Kuntz D Barth JA 《Journal of environmental management》2007,84(2):237-243
The integrated project "AquaTerra" with the full title "integrated modeling of the river-sediment-soil-groundwater system; advanced tools for the management of catchment areas and river basins in the context of global change" is among the first environmental projects within the sixth Framework Program of the European Union. Commencing in June 2004, it brought together a multidisciplinary team of 45 partner organizations from 12 EU countries, Romania, Switzerland, Serbia and Montenegro. AquaTerra is an ambitious project with the primary objective of laying the foundations for a better understanding of the behavior of environmental pollutants and their fluxes in the soil-sediment-water system with respect to climate and land use changes. The project performs research as well as modeling on river-sediment-soil-groundwater systems through quantification of deposition, sorption and turnover rates and the development of numerical models to reveal fluxes and trends in soil and sediment functioning. Scales ranging from the laboratory to river basins are addressed with the potential to provide improved river basin management, enhanced soil and groundwater monitoring as well as the early identification and forecasting of impacts on water quantity and quality. Study areas are the catchments of the Ebro, Meuse, Elbe and Danube Rivers and the Brévilles Spring. Here we outline the general structure of the project and the activities conducted within eleven existing sub-projects of AquaTerra. 相似文献
83.
基于哈萨克斯坦阿拉木图站和新疆乌鲁木齐站、伊宁站的1967-2009年1月份的降水资料,利用一元线性回归法、Mann-Kendall突变检验和Morlet小波分析的方法,分析了该区域降水的变化特征,结果表明:阿拉木图和伊宁1月份降水变化不明显,呈微弱的下降趋势;乌鲁木齐降水呈显著增加趋势。阿拉木图降水年代际变化不明显,乌鲁木齐于20世纪80年代以前降水偏少,此后降水逐渐增多,伊宁和乌鲁木齐年代际变化相似。阿拉木图1月份降水没有发生突变,在1980年以前存在6—7年的短周期变化,此后存在10—15年的长周期变化。伊宁1月份降水没有发生突变,1980年以前存在6年的短周期变化,此后存在8年和11年的周期变化,变化周期不稳定。乌鲁木齐于1978、1981发生了突变,存在6年左右和12年周期变化。 相似文献
84.
Ahmed M. Reda Ahmed Hamza H. Ali Ibrahim S. Taha Mahmoud G. Morsy 《International Journal of Green Energy》2017,14(1):75-85
In this study, an experimental investigation on the performance of a small-scale residential-size solar-driven adsorption (silica gel-water) cooling system that was constructed at Assiut University campus, Egypt is carried out. As Assiut area is considered as hot, arid climate, field tests for performance assessment of the system operation during the summer season are performed under different environmental operating conditions. The system consists of an evacuated tube with a reflective concentration parabolic surface solar-collector field with a total area of 36 m2, a silica gel-water adsorption chiller of 8 kW nominal cooling capacity, and hot and cold water thermal storage tanks of 1.8 and 1.2 m3 in volume, respectively. The results of summer season field test show that under daily solar insolation varying from 21 to 27 MJ/m2, the solar collectors employed in the system had high and almost constant thermal efficiency. The daily solar-collector efficiency during the period of system operation ranged from about 50% to 78%. The adsorption chiller performance shows that the chiller average daily coefficient of performance (COP) was 0.41 with the average cooling capacity of 4.4 kW when the cooling-water and chilled-water temperatures were about 31°C and 19°C, respectively. As the chiller cooling water is cooled by the cooling tower in the hot arid area, the cooling water is at a higher temperature than the design point of the chiller. Therefore, an experiment was carried out using the city water for cooling. The results show that an enhancement in the chiller COP by 40% and the chilling power by 17% has been achieved when the city water was 27.7°C. 相似文献
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86.
为了探究受损挡土墙结构的稳定性预警方法,首先分析挡墙-土体系统受力状态和土压力与挡墙稳定性及土体基床系数之间的关系;其次基于小波包频带能量谱分析,提出损伤预警指标——能量比变异系数(ERVC);然后分析ERVC、土压力及挡墙稳定性三者间的内在联系,提出一种用于损伤状态下的挡墙结构稳定性预警方法,即通过ERVC预警挡墙的稳定状态;最后以某桩板式挡墙为例,建立墙-土系统简化力学模型及其有限元模型,并修正有限元模型参数,得到墙-土系统基准有限元模型,以验证该预警方法的有效性。结果表明:随ERVC增大,挡墙稳定性逐渐降低;当ERVC达到界限值时,挡墙进入临界稳定状态。 相似文献
87.
为研究城市近地面臭氧浓度变化特征及臭氧浓度高值与气象因素的关系,于2015年夏季对济南城区近地面臭氧进行了观测与分析。结果表明:夏季大气中臭氧小时平均浓度为0.161 mg/m~3。臭氧具有明显的日变化特征,且晴天时臭氧浓度要比多云天气和阴雨时的浓度更高。高浓度臭氧的产生是多个气象因子共同作用的结果。一般晴天少云,气温较高,相对湿度较低,风速较小时,容易产生高浓度臭氧污染。 相似文献
88.
农村污染防治工作已迫在眉睫 总被引:1,自引:0,他引:1
针对目前农村经济发展过程中出现的主要环境问题,结合农村的实际情况,提出了解决农村环境污染问题的几项措施。并着重分析了规模化畜禽养殖业中的环境污染问题,提出了综合防治对策。 相似文献
89.
飞机的雷击附着点是飞机防雷设计研究的基础,是飞机设计中的重要过程。本文以伊尔-76飞机模型为例,依据SAE-ARP5416和国内相关标准规定的雷击附着点试验方法,采用基于传输线矩阵法的数值仿真技术对飞机的雷击附着特性展开研究,分析了机载雷达天线对飞机雷击附着点的影响,为机载雷达天线的雷电防护设计提供了理论基础。 相似文献
90.
Alternative livelihoods programmes (ALPs) are extensively executed in mining communities, often as models of development dialogue on artisanal and small‐scale mining (ASM). This paper assesses whether Prestea's ALP aligns with the development dialogue on artisanal mining. The conceptual design of ALP in Ghana's Prestea is based on the notions of substitution, homogenous community, and impact scalability. This paper argues that the Prestea ALP is not aligned with the development dialogue on artisanal mining, and therefore it is difficult to understand the role and function of environmentally‐damaging behaviours within livelihood strategies. The paper contends that it would be appropriate to concentrate on improving the existing artisanal miners’ operation of those most susceptible to resource access restrictions. Further, it may be more prudent to utilize livelihood‐centered interventions that create strong connections with sustainable development as a way of creating regular community engagements. Additionally, this paper argues that the term for the intervention programme on artisanal mining should be replaced with the broader term ‘livelihood‐centered intervention’. The replacement of the term ‘ALP’ avoids the tacit belief that ALP can adequately replace artisanal mining operations. Livelihood‐centered intervention should not necessarily utilize alternative livelihoods as direct behavioural change instruments. 相似文献