全文获取类型
收费全文 | 1985篇 |
免费 | 85篇 |
国内免费 | 700篇 |
专业分类
安全科学 | 110篇 |
废物处理 | 136篇 |
环保管理 | 123篇 |
综合类 | 1078篇 |
基础理论 | 346篇 |
污染及防治 | 773篇 |
评价与监测 | 81篇 |
社会与环境 | 73篇 |
灾害及防治 | 50篇 |
出版年
2023年 | 34篇 |
2022年 | 112篇 |
2021年 | 105篇 |
2020年 | 53篇 |
2019年 | 60篇 |
2018年 | 79篇 |
2017年 | 83篇 |
2016年 | 101篇 |
2015年 | 105篇 |
2014年 | 154篇 |
2013年 | 178篇 |
2012年 | 149篇 |
2011年 | 174篇 |
2010年 | 129篇 |
2009年 | 142篇 |
2008年 | 148篇 |
2007年 | 121篇 |
2006年 | 102篇 |
2005年 | 73篇 |
2004年 | 72篇 |
2003年 | 74篇 |
2002年 | 44篇 |
2001年 | 67篇 |
2000年 | 54篇 |
1999年 | 47篇 |
1998年 | 60篇 |
1997年 | 44篇 |
1996年 | 37篇 |
1995年 | 32篇 |
1994年 | 21篇 |
1993年 | 28篇 |
1992年 | 19篇 |
1991年 | 17篇 |
1990年 | 16篇 |
1989年 | 8篇 |
1988年 | 12篇 |
1987年 | 3篇 |
1986年 | 3篇 |
1985年 | 7篇 |
1983年 | 2篇 |
1981年 | 1篇 |
排序方式: 共有2770条查询结果,搜索用时 93 毫秒
31.
仇伟光 《辽宁城乡环境科技》2004,24(5):3-4
阐述了清洁生产和技术改造之间的关系,并通过实例进行了说明,得出将清洁生产理念融入到老工业基地的技术改造之中是企业实现经济和环境双赢的有效途径。 相似文献
32.
中国东部主要河流河水腐殖酸的起源、含量及地域分异规律 总被引:7,自引:6,他引:7
测定了中国东部地区主要河流河水、悬浮物和沉积物中腐殖酸含量,研究了该地区河水腐殖酸含量的地域分异规律,并探讨了河水腐殖酸的可能来源。结果表明,所研究河流河水腐殖酸含量在0.9—14.4mg/L范围内,中值为4.16mg/L,并有北高南低的一般趋势。黑龙江上游及松花江北部支流的河水腐殖酸含量在8.5mg/L以上,滦河以北其它地区在3.9—6.4mg/L范围内,黄河以南区域则在0.9—3.3mg/L之间,所研究地区河水中的腐殖酸为混合起源的,它既来自河流悬浮物和沉积物中腐殖酸的释放,又来自流域表土中腐殖酸的淋溶。 相似文献
33.
Gong Peiyu Li Xiuzhen Wu Kunjun Shu Jianmin Cao Hongfa Institute of Zookogy Academia Sinica Beijing ChinaInstitute of Zookogy Chinese Research Academy of Environmental Science Beijing China 《环境科学学报(英文版)》1990,(4)
This paper deals with effects of airborne fluorine on the army worm, Mythimna separata (Walker), by rearing the larvae on the wheat foliage exposed to HF or fumigating the larvae on the artificial diet with the pollutant. Larval relative growth rate (GR) and index of population trend of the insect reduced by 5% and 11%, respectively, when the larvae were reared on the foliage taken from the wheat plants exposed to 0.87 g·dm-2·day-1 of fluorine compared with those of the control. An extra instar appeared in a majority of the larvae treated. Survival rate and GR of the larvae on the wheat plant being exposure to the same concentration of fluorine in field open-top fumigation device were 40% and 15% lower than that of the control, respectively. Similar experiment with the insect on the artificial diet also showed that direct impact of the pollutant on the army worm was greater than its indirect effect via their host plant. 相似文献
34.
35.
36.
37.
The effects of land use and its patterns on soil properties in a small catchment of the Loess Plateau 总被引:3,自引:0,他引:3
Due to relatively strong human activities in the hilly area of Loess Plateau,the natural vegetation has been destroyed,and landscape pattern based on agricultural land matrix was land use mosaic composing of shrub land,grassland,woolland and orchard.This pattern has an important effect on soil moisture and soil nutrients.The Danangou catchment,a typical small catchment,was selected to study the effects of land use and its patterns on soil moisture and nutrients in this paper.The results are as follows:The comparisons of soil moisture among seven land uses for wet year and dry year were performed:(1)the average of soil moisture content for whole catchment was 12.11% in wet year,while it was 9.37% in dry year;(2)soil moisture among seven land uses was significantly different in dry year,but not in wet year;(3) form wet year to dry year,the profile type of soil moisture changed from decreasing type to fluctuation-type and from fluctuant type to increasing type;(4)the increasing trend in soil moisture from the top to foot of hillslope occurred in simple land use along slope,while complicated distribution of soil moisture was observed in multiple land uses along slope.The relationships between soil nutrients and land uses and landscape positions were analysed:(1)five nutrient contents of soil organic matter(SOM),total N(TN),available N(AN),total P(TP) and available P(AP) in hilly area were lower than that in other areas.SOM content was less than 1%,TN content less than 0.07%,and TP fallow land and cropland,and higher level in soil fertility was found in crop-fruit intercropping land among croplands;(3)soil nutrient distribution and responses to landscape positions were variable depending on slope and the location of land use types. 相似文献
38.
39.
40.
强化混凝去除黄浦江水有机物的试验研究 总被引:11,自引:0,他引:11
强化混凝去除有机物的效果与水源的分子量分布特性有着密切的关系.由于黄浦江水中低分子量的溶解性有机物占多数,因此,强化混凝处理有机物效果有限.对于<1k分子量区间的有机物.增加混凝剂投量可有效去除紫外吸光值(UV254),但去除溶解性有机碳(DOC)的效果很差.尽管增加混凝剂投量和降低pH都能有效地去除有机物,但决定强化混凝效果的主要因素是pH,去除黄浦江水有机物的最佳pH范围为6~5. 相似文献