全文获取类型
收费全文 | 228篇 |
免费 | 10篇 |
国内免费 | 49篇 |
专业分类
安全科学 | 12篇 |
废物处理 | 10篇 |
环保管理 | 20篇 |
综合类 | 115篇 |
基础理论 | 33篇 |
污染及防治 | 53篇 |
评价与监测 | 13篇 |
社会与环境 | 15篇 |
灾害及防治 | 16篇 |
出版年
2023年 | 6篇 |
2022年 | 9篇 |
2021年 | 10篇 |
2020年 | 6篇 |
2019年 | 4篇 |
2018年 | 11篇 |
2017年 | 5篇 |
2016年 | 3篇 |
2015年 | 7篇 |
2014年 | 16篇 |
2013年 | 17篇 |
2012年 | 20篇 |
2011年 | 14篇 |
2010年 | 7篇 |
2009年 | 16篇 |
2008年 | 19篇 |
2007年 | 15篇 |
2006年 | 8篇 |
2005年 | 6篇 |
2004年 | 12篇 |
2003年 | 8篇 |
2002年 | 18篇 |
2001年 | 11篇 |
2000年 | 10篇 |
1999年 | 9篇 |
1998年 | 5篇 |
1997年 | 3篇 |
1996年 | 2篇 |
1994年 | 5篇 |
1991年 | 2篇 |
1990年 | 1篇 |
1983年 | 1篇 |
1981年 | 1篇 |
排序方式: 共有287条查询结果,搜索用时 15 毫秒
131.
以松嫩平原西部为例,在构建生态环境胁迫评价指标体系的基础上,运用分形理论对生态环境胁迫进行量化研究.结果表明,1989-2004年15 a间,除松原市和扶余县以外,其他县市生态环境胁迫系数都呈增大趋势,特别是大安市、长岭县、乾安县等地胁迫系数较大.采用相对指标法,运用GIS-EIS集成技术,对松嫩平原西部生态环境胁迫度进行分级.最后,分析了影响生态环境胁迫变化的驱动因子,并提出减缓生态环境胁迫的措施. 相似文献
132.
133.
太行山前平原农牧结构模式评价与配套技术体系 总被引:7,自引:0,他引:7
农牧结构生产模式是太行山前平原农业生产的重要模式。苜蓿具有明显的经济效益、水分效益和土壤培肥作用。种植-畜牧模式农田亚系统可节约灌溉35%、具有显著的经济效益和能效,苜蓿氮、磷产出投入率远高于小麦-玉米两熟制和棉花;畜牧亚系统氮素327%、磷素259%可归还农田亚系统,实行一定程度的养分循环。农牧结构优化模式的配套技术体系体现在制定合理的农牧比例、农田亚系统高效管理、调整畜牧结构、秸秆饲用处理、饲料作物和牧草种植技术以及农牧物质循环技术,其中制定合理的农牧比例、调整畜牧结构是关键。综合协调应用这些技术,最终能够实现提高农牧结构优化模式农业资源综合利用效率20%~30%的目标。 相似文献
134.
Hung-Che Wu Ching-Chan Cheng Chi-Han Ai 《Journal of Environmental Planning and Management》2018,61(8):1438-1468
The purpose of this research is to gain an empirical understanding of airline passengers’ green switching intentions. A conceptual research model is used as a framework to examine the relationships among the experiential quality dimensions, green perceived value, green corporate image, green experiential satisfaction, green corporate reputation, green experiential loyalty and green switching intentions for the airline industry. The data used in this paper were based on a sample of 615 passengers who experienced the eco-friendly services of China Airlines, indicating that the proposed model fitted the data. The study's result will assist airline management to develop and implement market-orientated service strategies to increase the experiential quality dimensions, green perceived value, green corporate image, green experiential satisfaction, green corporate reputation and green experiential loyalty in order to decrease passengers’ green switching intentions. 相似文献
135.
136.
用四-(对氨基苯基)-卟啉柱前衍生的高效液相色谱法测定重金属 总被引:4,自引:0,他引:4
研究了用固相萃取富集、快速分离柱高效液相色谱法测定环境水样中镍、锡、铅、镉、汞5种重金属的方法。环境水样中的镍、锡、铅、镉、汞用四-(对氨基苯基)-卟啉(T4APP)柱前衍生,然后用ZORBAX RP18固相萃取小柱萃取富集镍、锡、铅、镉、汞的T4APP络合物,经富集后的络合物用甲醇-丙酮(体积比95∶5)为流动相,ZORBAX Stab le Bound(4.6 mm×50 mm,1.8μm)快速分离柱为固定相分离,用二极管矩阵检测器检测。镍、锡、铅、镉、汞的检测限分别为4,5,4,3,3 ng/L,分离5种重金属元素络合物的时间只需2.0 m in,相对标准偏差为2.2%~4.1%,加标回收率为88%~104%。用该法测定环境水样中的痕量镍、锡、铅、镉、汞,结果令人满意。 相似文献
137.
Ai H. Shang Dong H. Chen Xiao X. Lu Hai D. Lu Chao N. Liu 《Journal of environmental science and health. Part. B》2013,48(11):809-818
This study aimed to evaluate the aquatic toxicity of three typical tetracycline antibiotics, including tetracycline, oxytetracycline, and chlortetracycline, on the cyanobacterium Microcystis aeruginosa. The cell density, chlorophyll a content, protein content, and enzymatic antioxidant activities were determined. The results showed that the cell growth was significantly inhibited by the three compounds at a low concentration. The chlorophyll a and protein content decreased significantly after exposure to 0.05 mg L?1 of each compound for 9 d. When exposed to 0.2–1 mg L?1 of tetracycline, the superoxide dismutase (SOD) activity increased, but peroxidase (POD) and catalase (CAT) activities decreased. In contrast, when exposed to oxytetracycline and chlortetracycline at different concentrations ranging from 0.2 to 1 mg L?1 and from 0.01 to 0.05 mg L?1, the SOD activity decreased, but the POD and CAT activities increased. These findings indicate that tetracycline antibiotics influence cell growth and protein synthesis, and they also induce oxidative stress in M. aeruginosa at environmentally similar concentrations. Thus, this study may provide further insights into the toxic effects of tetracycline antibiotics and the controlled use of antibiotics. 相似文献
138.
139.
Husnain Husnain I. G. Putu Wigena Ai Dariah Setiari Marwanto Prihasto Setyanto Fahmuddin Agus 《Mitigation and Adaptation Strategies for Global Change》2014,19(6):845-862
With the increasing use of tropical peatland for agricultural development, documentation of the rate of carbon dioxide (CO2) emissions is becoming important for national greenhouse gas inventories. The objective of this study was to evaluate soil-surface CO2 fluxes from drained peat under different land-use systems in Riau and Jambi Provinces, Sumatra, Indonesia. Increase of CO2 concentration was tracked in measurement chambers using an Infrared Gas Analyzer (IRGA, LI-COR 820 model). The results showed that CO2 flux under oil palm (Elaeis guineensis) plantations ranged from 34?±?16 and 45?±?25 Mg CO2 ha–1 year–1 in two locations in Jambi province to 66?±?25 Mg CO2 ha–1 year–1 for a site in Riau. For adjacent plots within 3.2 km in the Kampar Peninsula, Riau, CO2 fluxes from an oil palm plantation, an Acacia plantation, a secondary forest and a rubber plantation were 66?±?25, 59?±?19, 61?±?25, 52?±?17 Mg ha–1 year–1, respectively, while on bare land sites it was between 56?±?30 and 67?±?24 Mg CO2 ha–1 year–1, indicating no significant differences among the different land-use systems in the same landscape. Unexplained site variation seems to dominate over land use in influencing CO2 flux. CO2 fluxes varied with time of day (p?<?0.001) with the noon flux as the highest, suggesting an overestimate of the mean flux values with the absence of night-time measurements. In general, CO2 flux increased with the depth of water table, suggesting the importance of keeping the peat as wet as possible. 相似文献
140.