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251.
厌氧反应器技术研究开发情况简介 总被引:2,自引:0,他引:2
楼静 《中国环境管理干部学院学报》2002,12(3):37-40
本文分析了厌氧反应器技术的发展过程,着重介绍了几种新型第三代厌氧反应器技术的原理和应用现状,以及我国目前对这些技术的研究开展情况,其中:升流式厌氧污泥床过滤器(UBF)研究取得了一定的成功经验;垂直折流厌氧污泥床反应器(VBASBR)缺乏应用生产实例;厌氧折流反应器(ABR)已有成功经验;内循环反应器(IC)还只限于部分废水的处理;膨胀颗粒污泥床反应器(ECSB)尚未有规模的生产投入使用。 相似文献
252.
本文提出了一种长三角区域性PM2.5污染日的判别方法,以出现5个、8个连片污染城市为检验阈值,分别覆盖了96%和100%的区域污染日.然后利用T-mode斜交旋转分解方法(PCT)对2015—2018年11—2月长三角地区260个区域性PM2.5污染日进行分型,揭示了4种不同的PM2.5的空间分布形态(整体型、西部型、西北型和东北型),其影响范围、持续时间和污染程度存在显著差异.其中,整体型污染受L型高压控制,出现日数最多(139 d)、覆盖范围最广(31个城市)、区域平均浓度最高(104.3 μg·m-3),是影响长三角地区PM2.5环境质量的最重要的污染类型.西部型和西北型分别受东路冷空气、西路冷空气影响,PM2.5分别呈现"西高东低"、"北高南低"的分布形态,前者主要影响安徽大部和浙江北部,后者主要影响安徽北部和江苏西北部.东北型是长三角本地排放在弱气压场和高压中心下混合产生,主要影响江苏大部和上海,基本不受跨区域输送影响.针对不同类型的污染影响范围和程度可以采取差异化的大气污染联防联控措施. 相似文献
253.
讨论了BP网络模型存在的不足。提出了建立合理的BP网络模型的基本原则和步骤。针对水质评价与预测问题。通过在各类水质污染指标浓度区间内生成随机分布样本的方法。组成足够多用于BP网络训练、检验和泛化能力评定用的样本。建立了南京市秦淮外河水体水质评价的BP网络模型:给出了区分不同类别水质的模型分界值样本和模型输出分界值。用概率分布理论分析处于相邻类别水质过渡状态水体的水质属性。建立的水质评价模型应用于实例表明。南京市秦淮外河水体1991—1996年水质为V类向IV类转变。1992年水质最差,1996年水质最好。灰色动态预测模型计算表明。从1997到2001年。南京市秦淮外河水体水质逐年变好。 相似文献
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255.
Kunyu Jiang Zhaowen Cheng Ziyang Lou Luochun Wang Hailin Lu Bijun Xu Ningben Jin 《环境科学学报(英文版)》2021,33(5):196-206
The explosive increase of construction and demolition waste (CDW) caused the insufficient source separation and emergency disposal at domestic waste landfills in many developing countries. Some organic fractions were introduced to the CDW landfill process and resulted in serious odor pollution. To comprehensively explore the impacts of organic matters on odor emission patterns, five CDW landfills (OIL), with organic matters/ inert CDW components (O/I) from 5% to 30%, and the control group only with inert components (IL) or organics (OL) were simulated at the laboratory. The chemical and olfactive characters of odors were evaluated using the emission rate of 94 odorants content (ERtotal), theory odor concentration (TOCtotal), and e-nose concentration (ERENC), and their correlations with waste properties were also analyzed. It was found that the main contributors to ERtotal (IL: 93.0% NH3; OIL: 41.6% sulfides, 31.0% NH3, 25.9% oxygenated compounds) and TOC total (IL: 64.1% CH3SH, 28.2% NH3; OIL: 71.7% CH3SH, 24.8% H2S) changed significantly. With the rise of O/I, ERtotal, TOCtotal, and ERENC increased by 10.9, 20.6, and 2.1 times, respectively. And the organics content in CDW should be less than 10% (i.e., DOC<101.3 mg/L). The good regressions between waste properties (DOC, DN, pH) and (r=0.86, 0.86, -0.88, p<0.05), (r=0.82, 0.79, -0.82, p<0.05) implied that the carbon sources and acidic substances relating to organics degradation might result in that increase. Besides, the correlation analysis results ( vs. , r=0.96, p<0.01; vs. , r=0.86, p<0.05) indicated that e-nose perhaps was a reliable odor continuous monitoring tool for CDW landfills. 相似文献
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257.
采用机械燃烧方式和炉膛内部改造相结合方法以及装设省煤器和除尘器等技措施,对阜阳市青峰机械厂K4锅炉进行技术改造,不仅使排放烟尘达到国家标准,而且提高了锅炉热效率.经过几年运行实践,解决了K4锅炉烟尘污染问题,该方法对于保护环境,节约能源有较大的实用价值. 相似文献
258.
Mary Lou Thompson Lawrence H. Cox Paul D. Sampson David C. Caccia 《Environmental and Ecological Statistics》2002,9(4):321-339
Environmental regulatory standards are intended to protect human health and environmental welfare. Current standards are based on scientific and policy considerations but appear to lack rigorous statistical foundations and may have unintended regulatory consequences. We examine current and proposed U.S. environmental regulatory standards for ozone from the standpoint of their formulation and performance within a statistical hypothesis testing framework. We illustrate that the standards can be regarded as representing constraints on a percentile of the ozone distribution, where the percentile involved depends on the defined length of ozone season and the constraint is stricter in regions with greater variability. A hypothesis testing framework allows consideration of error rates (probability of false declaration of violation and compliance) and we show that the existing statistics on which the standards are based can be improved upon in terms of bias and variance. Our analyses also raise issues relating to network design and the possibilities of defining a regionally based standard that acknowledges and accounts for spatial and temporal variability in the ozone distribution. 相似文献
259.
Shujuan Lou Jietai Mao Meihua Wang 《Frontiers of Environmental Science & Engineering》2007,1(3):345-349
The objective of this study was to determine the black carbon concentration in Beijing in 2003. The aerosol properties were measured using an Aethalometer and a tapered element oscillating microbalance (TEOM) on the roof of the Physics Building of Peking University (39.99° N, 116.31° E) from July to August 2003 and from November 2003 to January 2004. The average black carbon (BC) concentrations in the summer and winter were 8.80 and 11.4 μg/m3, respectively. During winter, two different cyclone cut offs were installed at the inlet of an aethalometer. The BC mass concentration in TSP, PM10, and PM2.5 were obtained. The results indicated that in winter aerosol, 90% of BC exited in PM10 and 82.6% of BC exited in PM2.5. The BC in PM10 accounted for 5.11% of the PM10 mass. 相似文献
260.