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101.
102.
介绍一种新型蒸汽喷射离子发生器,并将这种发生器作为预荷电器,在旋风除尘器上进行除尘增效改造应用的试验。结果表明粉尘的预荷电及静电凝并可以增加除尘效率。  相似文献   
103.
李晖  邹惠仙 《环境化学》1995,14(2):124-128
在25℃下,分别测定来自水各地的四种土壤和八种沉积物吸着水溶液中的1,2-二氯苯和四氯化碳的吸附等温线,所有的等温线呈线性,表明土壤和沉积物吸着水溶液中的非离子有机物的过程是分配机理,土壤或沉物的本身用有机碳标化的吸附系数(Koc)之间差异不大,而土壤的和沉积物之间的Koc则存在显著性差异,这是由于沉积物有机质成分的极性小于土壤有机质成分的极性造成的,沉积物质吸着上述两种有机物的Koc约是土壤的K  相似文献   
104.
综述从活动断裂的研究和进展出发,通过追溯国内外活动断裂研究发展历史,结合当前城市活动断裂研究的理论与方法,认为地球物理的综合物探手段在城市活断层探测工作中将会越来越重要。文中重点介绍了城市活断层探测工作中所采用的地球物理方法的类型,以及在区域探查与初步鉴定阶段、详细探测与精确定位阶段、孕震构造探测阶段可能涉及到的各种地球物理探测方法、适用范围及所能解决的主要问题等。文章结合哈尔滨城市活断层探测项目实例,表明在面对岩石和地层的众多物性差异和勘查结果的多解性时,地球物理的综合物探方法在提高资料的反演和解译准确度方面具有十分重要的意义。  相似文献   
105.
燃油锅炉燃烧过程SO2的生成与排放特征   总被引:1,自引:0,他引:1  
燃料燃烧过程是大气污染物的重要来源之一,对人体健康、空气质量和气候变化产生非常重要的影响。以62台燃油锅炉(≤10.5 MW)的燃料特性分析数据和SO2排放实测数据为基础,通过统计分析方法,研究了燃油燃烧过程中燃油硫含量S和过量空气系数α对硫的转化率、SO2排放因子和排放浓度的影响,获得了基于燃料消耗量、燃料发热量的SO2排放因子EFCEFH以及SO2标态折算浓度CSO2与硫含量S间的关联式。结果表明,在过量空气系数α>1的燃油燃烧过程中,EFCEFHCSO2与燃油硫含量S呈现出显著的线性正相关性,而与过量空气系数α无关,其关系式分别为:EFC=18.86602×SEFH=443.78751×SCSO2=1 509.28337×S;硫转化率η和基于燃料硫含量的SO2排放因子EFS则与燃油硫含量S和过量空气系数α无关,其平均值分别为96.3%和1.93 kg/kg。  相似文献   
106.
Most available exposure-response relationships for assessing crop loss due to elevated ozone (O3) have been established using data from chamber and open-top chamber experiments, using a simulated constant O3 concentration exposure (square wave), which is not consistent with the diurnal variation of O3 concentration that occurs in nature. We investigated the response of oilseed rape (Brassica napus L.) to O3 as affected by two exposure regimes: one with a diurnal variation (CF100D) and another with a constant concentration (CF100). Although the two exposure regimes have the same mean O3 concentration and accumulated O3 concentration above 40 ppb (AOT40), our results show that O3 at CF100D reduced biomass and number of pods/plant more than O3 at CF100. Both O3 exposures resulted in larger seed weights/100 pods compared to CF. Numbers of seeds/100 pods were reduced by CF100, while numbers of seeds/100 pods in the CF100D chambers were comparable to those in CF. Our results suggest that chamber experiments that use a constant O3 exposure may underestimate O3 effects on biomass and yields.  相似文献   
107.
Ecotourism is widely promoted as a conservation tool and actively practiced in protected areas worldwide. Theoretically, support for conservation from the various types of stakeholder inside and outside protected areas is maximized if stakeholders benefit proportionally to the opportunity costs they bear. The disproportional benefit distribution among stakeholders can erode their support for or lead to the failure of ecotourism and conservation. Using Wolong Nature Reserve for Giant Pandas (China) as an example, we demonstrate two types of uneven distribution of economic benefits among four major groups of stakeholders. First, a significant inequality exists between the local rural residents and the other types of stakeholder. The rural residents are the primary bearers of the cost of conservation, but the majority of economic benefits (investment, employment, and goods) in three key ecotourism sectors (infrastructural construction, hotels/restaurants, and souvenir sales) go to other stakeholders. Second, results show that the distribution of economic benefits is unequal among the rural residents inside the reserve. Most rural households that benefit from ecotourism are located near the main road and potentially have less impact on panda habitat than households far from the road and closer to panda habitats. This distribution gap is likely to discourage conservation support from the latter households, whose activities are the main forces degrading panda habitats. We suggest that the unequal distribution of the benefits from ecotourism can be lessened by enhancing local participation, increasing the use of local goods, and encouraging relocation of rural households closer to ecotourism facilities.  相似文献   
108.
Viña A  Chen X  McConnell WJ  Liu W  Xu W  Ouyang Z  Zhang H  Liu J 《Ambio》2011,40(3):274-284
Conservation policies are increasing in response to human-induced ecosystem degradation, but little is known about their interplay with natural disasters. Through an analysis of satellite imagery and field data we evaluated the impacts of a devastating earthquake on forest recovery and avoided forest loss estimated to have been obtained by two of the largest conservation programs in the world. Results show that more than 10% of the forests in Wenchuan County, Sichuan province, China were immediately affected by the 2008 earthquake, offsetting some gains in forest cover observed since the enactment of the conservation programs. But without the enactment of these conservation programs, the combined effects of human disturbance and earthquake-induced landslides could have severely reduced the region’s forest cover. The continuation—and enhancement—of incentives for participation in conservation programs will be important for reducing the environmental impacts of the combined effects of human disturbance and natural hazards not only in the study area but also in many disaster-prone regions around the world.  相似文献   
109.
Environmental Science and Pollution Research - In order to explore the high value-added utilization of flyash adsorption in regenerating waste lubricating oil, the main factors related to the...  相似文献   
110.
Constructed wetland (CW) and constructed pond (CP) are commonly utilized for removal of excess nutrients and certain pollutants from stormwater. This study characterized shallow groundwater quality for pre- and post-CW and CP system conditions using data from monitoring wells. Results showed that the average concentrations of groundwater phosphorus (P) decreased from pre-CW to post-CW but increased from pre-CP to post-CP. The average concentrations of groundwater total Kjeldahl nitrogen and ammonium ( $ {\mathrm{NH}}{_4^{ + }} $ ) increased from pre-CW (or CP) to post-CW (or CP), whereas the average concentrations of groundwater arsenic (As), chromium, nickel, and zinc (Zn) decreased from pre-CW to post-CW regardless of the well locations. Variations of groundwater cadmium, copper, and Zn concentrations were larger in pre-CP than in post-CP and had a tendency to decrease from pre-CP to post-CP. In general, the average concentrations of groundwater aluminum and manganese decreased and of groundwater calcium, iron, magnesium, and sodium increased from pre-CP to post-CP. The average values of water levels (depth from the ground surface), redox potential, and conductance decreased and of chloride and sulfate ( $ {\mathrm{SO}}{_4^{{ - 2}}} $ ) increased after the wetland and pond were constructed regardless of the well locations. Results further revealed that there were significant differences (α?=?0.05) between the pre- and post-CW (or CP) for redox potential, water level, and As. This study suggests that the CW–CP system had discernible effects on some of the shallow groundwater quality constituents. This information is very useful for fully estimating overall performance of stormwater treatment with the CW–CP system.  相似文献   
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