全文获取类型
收费全文 | 182篇 |
免费 | 15篇 |
国内免费 | 32篇 |
专业分类
安全科学 | 34篇 |
废物处理 | 6篇 |
环保管理 | 34篇 |
综合类 | 99篇 |
基础理论 | 20篇 |
污染及防治 | 12篇 |
评价与监测 | 16篇 |
社会与环境 | 2篇 |
灾害及防治 | 6篇 |
出版年
2023年 | 1篇 |
2022年 | 2篇 |
2021年 | 3篇 |
2020年 | 4篇 |
2019年 | 2篇 |
2018年 | 2篇 |
2017年 | 4篇 |
2016年 | 4篇 |
2015年 | 12篇 |
2014年 | 6篇 |
2013年 | 11篇 |
2012年 | 13篇 |
2011年 | 15篇 |
2010年 | 15篇 |
2009年 | 10篇 |
2008年 | 8篇 |
2007年 | 19篇 |
2006年 | 11篇 |
2005年 | 8篇 |
2004年 | 16篇 |
2003年 | 8篇 |
2002年 | 8篇 |
2001年 | 8篇 |
2000年 | 5篇 |
1999年 | 5篇 |
1998年 | 1篇 |
1997年 | 1篇 |
1996年 | 2篇 |
1995年 | 4篇 |
1994年 | 4篇 |
1993年 | 4篇 |
1992年 | 6篇 |
1991年 | 1篇 |
1990年 | 1篇 |
1979年 | 1篇 |
1977年 | 1篇 |
1975年 | 1篇 |
1971年 | 1篇 |
1970年 | 1篇 |
排序方式: 共有229条查询结果,搜索用时 15 毫秒
151.
我国新的地震区划编图和中国地震烈度区划图(1990) 总被引:10,自引:1,他引:10
本文阐述了我国新的地震区划工作的科学思路和技术方法,探讨了若干重要专门术语的涵义,讨论了某些环节的处理所蕴含的假定,最后,介绍了新的地震烈度区划图的概貌. 相似文献
152.
Munro LT 《Disasters》2002,26(3):242-261
In 1992-3 and 1995-6, Zimbabwe used a Child Supplementary Feeding Programme (CSFP) to combat child malnutrition during drought-induced emergencies. Previous evaluations of the CSFP relied on routine administrative data and key informant interviews and made only cursory use of available household survey data. These evaluations concluded that the CSFP was effective in preventing an increase in malnutrition among children under five, especially in 1992-3. The more-detailed analysis of household surveys provided in this article suggests that CSFP coverage was generally patchy and disappointingly low, especially in 1995-6. There is little evidence that children from poor or nutritionally vulnerable households got preferential access to supplementary feeding. The CSFP failed to feed many malnourished and nutritionally vulnerable children even in areas where the programme was operating. Household survey evidence suggests that the CSFP's impact on nutritional status was likely marginal, especially in 1995-6. 相似文献
153.
154.
155.
测定挥发酚和氰化物时,用试剂空白代替全程序空白对结果进行校正,可省去全程序空白的预蒸馏,此法具有省时、省力、节水、节电等优点。 相似文献
156.
简要介绍了中国危险废物鉴别程序,围绕鉴别程序从三个方面总结了固体废物危险特性鉴别的经验。固体废物判断需把握待鉴别物品生产的目的、社会属性及其相对性,若物品是有意生产,或其社会属性符合行业通行做法和市场需求,则该物品不属于固体废物;危险废物名录查询需把握废物的行业来源与生产工艺特征,其中生产工艺分析是确定废物行业来源的关键;开展分析测试需充分论证废物检测指标及其样本数,基础资料的收集和专家咨询是完善固体废物危险特性鉴别的必要手段。 相似文献
157.
158.
159.
Implementing landscape fragmentation as an indicator in the Swiss Monitoring System Of Sustainable Development (Monet) 总被引:1,自引:0,他引:1
Jaeger JA Bertiller R Schwick C Müller K Steinmeier C Ewald KC Ghazoul J 《Journal of environmental management》2008,88(4):737-751
There is an increasing need and interest in including indicators of landscape fragmentation in monitoring systems of sustainable landscape management. Landscape fragmentation due to transportation infrastructure and urban development threatens human and environmental well-being by noise and pollution from traffic, reducing the size and viability of wildlife populations, facilitating the spread of invasive species, and impairing the scenic and recreational qualities of the landscape. This paper provides the rationale, method, and data for including landscape fragmentation in monitoring systems, using as an example the Swiss Monitoring System of Sustainable Development (Monet). We defined and compared four levels of fragmentation analysis, or fragmentation geometries (FGs), each based on different fragmenting elements, e.g., only anthropogenic, or combinations of anthropogenic and natural elements. As each FG has specific strengths and weaknesses, the most appropriate choice of FG depends on the context and objectives of a study. We present data on the current degree of landscape fragmentation for the five ecoregions and 26 cantons in Switzerland for all four FGs. Our results show that the degree of landscape fragmentation as quantified by the effective mesh size method is strongly supported by the postulates and indicator selection criteria of Monet, and we identify the most suitable FG focusing on the land area below 2100 m (e.g., excluding lakes) and allowing for an equitable comparison of fragmentation degrees among regions that differ in area covered by lakes and high mountains. For a more detailed analysis of landscape fragmentation in the context of environmental impact assessments and strategic environmental assessments, a combination of all four FGs may provide a more informative tool than any single FG. 相似文献
160.
为了解原生滨海滩涂不同植被演替带土壤镉(Cd)的含量特征、赋存形态及生态风险,以盐城地区原生滨海滩涂为研究对象,利用BCR 3步提取法分析了不同植被演替带土壤Cd的含量及赋存形态,并采用平均沉积物质量基准系数法(SQG-Q)和风险评价准则(RAC)对Cd的潜在生态风险进行了初步评价。结果表明,原生滩涂土壤中总Cd(CdT)含量在2.21~3.61 mg·kg~(-1)之间,远高于江苏沿海土壤Cd背景值和国家土壤环境质量三级标准;不同植被演替带间,CdT含量表现为互花米草滩碱蓬滩芦苇滩光滩;SQG-Q系数显示该地区土壤CdT处于中等风险,互花米草滩风险相对较高;总体上原生滩涂土壤中可还原态Cd比例较低(12.8%),而酸溶态、可氧化态、残渣态三者差异不大(分别为28.2%、29.8%,29.2%);互花米草滩和芦苇滩酸溶态Cd比例(30.5%、37.0%)显著高于碱蓬滩和光滩(28.2%、20.6%),而残渣态Cd(21.5%、20.9%)则显著低于碱蓬滩和光滩(41.5%、45.6%);RAC评价结果显示,滩涂土壤Cd总体上呈现中等风险,而互花米草滩和芦苇滩达到高风险。以上结果显示,原生滨海滩涂土壤Cd已存在一定的生态风险,其中互花米草滩风险相对较高,随着互花米草的扩张及围垦面积的扩大,其重金属风险值得关注。 相似文献