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151.
垃圾渗滤液中溶解性有机物对土壤中重金属迁移的影响   总被引:2,自引:0,他引:2  
垃圾渗滤液主要组分中含有重金属和大量的溶解性有机物(DOM).实验选用北方最具代表性的褐土为供试样品,通过室内土柱淋滤实验研究了垃圾渗滤液溶解性有机物对重金属Cu、Cd、Pb和Zn在土壤中的迁移行为的影响.结果显示,DOM对土壤中Cd、Zn的垂直迁移起着促进作用,而对Cu、Pb迁移起着一定的抑制作用;不同浓度的垃圾淋洗...  相似文献   
152.

Purpose  

Dimethyl phthalate esters (DMPEs) are a group of plasticizers commonly detected in the environment with potential adverse human health impact. The degradation of DMPEs by fungal systems has been studied to a limited extent, particularly by yeasts. In this study, a basidiomycetous yeast Trichosporon DMI-5-1 capable of degrading DMPEs was obtained and the degradation pathways were investigated.  相似文献   
153.
建筑物对高架点源大气污染物扩散影响的模拟研究   总被引:2,自引:0,他引:2  
运用数值方法对城市中高架点源排放大气污染物的扩散规律进行了模拟研究,在计算区域内建立了三维数学模型,并将拉格朗日法描述的颗粒轨道模型耦合到风场。本研究计算了地面风速为3 m/s时的大气流场,并模拟研究了该风场条件下气体污染物的扩散和固体颗粒污染物的运动轨迹。通过分析模拟结果,给出了高架点源中排放的气体污染物的扩散区域和固体颗粒污染物运动轨迹的变化规律。  相似文献   
154.
Environmental Fluid Mechanics - We introduce a mathematical model with a mesh-free numerical method to describe contact-line motion in lubrication theory. We show how the model resolves the...  相似文献   
155.
Environmental Science and Pollution Research - Arsenic is a toxic heavy metal widely found in the natural environment and has adverse effects on the health of waterfowl and human. Curcumin (CUR), a...  相似文献   
156.

Agricultural irrigation water in Northwest China accounts for more than 80% of total local water consumption, which is 1.23 times that of China. However, Northwest China is the most water-scarce place in China. Water scarcity in restricts crop growth and production. Reference crop evapotranspiration (ET0) is important for agricultural water management. Understanding the reason for ET0 change is helpful to provide a basis for rational planning of agricultural irrigation systems to conserve water. This study investigated the temporal and spatial variation characteristics of ET0 at 181 meteorological stations in Northwest China from 2000 to 2019. And the sensitive factors and dominant factors affecting ET0 change were quantitatively identified based on sensitivity analysis and contribution rate evaluation. Results showed that (1) a significant increase in maximum and minimum temperature (Tmax and Tmin), a significant decrease in sunshine duration (SD) and relative humidity (RH), and a slight increase in wind speed at 10 m height (U10) were observed. (2) Annual ET0 had an insignificant increasing trend. Spring and autumn ET0 contributed greatly to the growth of annual ET0, especially in March, May, September, October, and November. ET0 in HH (Yellow River Basin area) had decreased at annual scale, while other subregions were the opposite trend. Significant differences in monthly and seasonal changes in the spatial distribution of ET0. (3) U10 was the dominating contribution factor related to annual ET0 variability, followed by Tmin, RH, Tmax, and SD. In seasonal time scale, Tmin, SD, U10, and RH were the most dominant factors in spring, summer, autumn, and winter respectively. (4) Spatial distribution for contribution rates of various meteorological factors showed significant diversity among various subregions. The positive contribution of U10 was the major cause of the increase in ET0 in semi-arid grassland area (BGH), the southwest of “Qice line” (QCXXN), and the southeast of “Qice line” (QCXDN); the significant increase in Tmin contributed most in Qaidam Basin (CDM), Hexi inland river basin (HX), the northeast of “Qice line” (QCXDB), and the northwest of “Qice line” (QCXXB), while the contribution of decreasing SD offsets the positive effects of other factors, leading to the decrease in ET0 in HH. Our work illustrates that water management measures should be different at different spatial and temporal scales. The effect of U10 can be offset by covering, to reduce evaporation and maintain water in BGH, QCXXN, and QCXDN. And high-temperature resistant varieties are planted to adapt to temperature growth in CDM, HX, QCXDB, and QCXXB. Agricultural water management strategies should be formulated and selected according to local conditions.

  相似文献   
157.
Environmental Science and Pollution Research - To comprehensively understand the toxic risks of phthalates to aquatic ecosystems, we examined the acute toxicity of di-(2-ethylhexyl) phthalate...  相似文献   
158.
庞卫锋   《化工环保》2008,28(1):89-92
用泰德拉气体采样袋采样,自动进样气相色谱法测定气体中的非甲烷烃含量。甲烷、总烃的线性范围分别为0~2439,0—2066mg/m^3。进样量为1mL时,检出限为0.02mg/m^3(信噪比为3)。对3种不同浓度甲烷与丙烷混合标准气进行测定,重复性相对标准偏差为0.4%-1.0%。对4种不同性质的试样进行加标回收实验,加标回收率为96.7%-102.0%。5名实验人员分别用自动进样法及手动进样法分析4种不同性质的试样,自动进样法的重现性相对标准偏差为1.2%~1.8%,优于手动进样法的6.5%~8.3%。该法可一次连续测定21个试样,精密度高、重现性好、分析效率高。  相似文献   
159.
两种填埋结构中氨氮的空间变化规律研究   总被引:1,自引:0,他引:1  
依据准好氧填埋和厌氧填埋的原理,构建了准好氧和厌氧填埋的实验室模拟装置,研究了2种填埋结构渗滤液中氨氮的空间分布规律。结果表明,准好氧填埋结构3层渗滤液中氨氮浓度都呈不断稳定下降的趋势,29周时上层、中层和下层渗滤液中氨氮浓度分别从填埋初的931.8、1796和3019 mg/L下降到25.6、328.9和820.1 mg/L;厌氧填埋结构3层渗滤液中氨氮浓度下降趋势不明显且波动性较大。准好氧填埋与厌氧填埋结构渗滤液中氨氮浓度表现出明显的空间层次效应,为下层>中层>上层。  相似文献   
160.
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