全文获取类型
收费全文 | 85291篇 |
免费 | 1216篇 |
国内免费 | 1065篇 |
专业分类
安全科学 | 3646篇 |
废物处理 | 3033篇 |
环保管理 | 13309篇 |
综合类 | 20886篇 |
基础理论 | 25571篇 |
环境理论 | 74篇 |
污染及防治 | 12157篇 |
评价与监测 | 5129篇 |
社会与环境 | 3288篇 |
灾害及防治 | 479篇 |
出版年
2022年 | 779篇 |
2021年 | 781篇 |
2020年 | 640篇 |
2019年 | 853篇 |
2018年 | 1061篇 |
2017年 | 1080篇 |
2016年 | 2085篇 |
2015年 | 1814篇 |
2014年 | 2555篇 |
2013年 | 9204篇 |
2012年 | 1957篇 |
2011年 | 2053篇 |
2010年 | 3149篇 |
2009年 | 3288篇 |
2008年 | 1542篇 |
2007年 | 1352篇 |
2006年 | 1887篇 |
2005年 | 1969篇 |
2004年 | 2287篇 |
2003年 | 2107篇 |
2002年 | 1665篇 |
2001年 | 1867篇 |
2000年 | 1776篇 |
1999年 | 1410篇 |
1998年 | 1341篇 |
1997年 | 1324篇 |
1996年 | 1447篇 |
1995年 | 1540篇 |
1994年 | 1440篇 |
1993年 | 1292篇 |
1992年 | 1273篇 |
1991年 | 1252篇 |
1990年 | 1198篇 |
1989年 | 1168篇 |
1988年 | 1007篇 |
1987年 | 956篇 |
1986年 | 982篇 |
1985年 | 1049篇 |
1984年 | 1143篇 |
1983年 | 1157篇 |
1982年 | 1168篇 |
1981年 | 1087篇 |
1980年 | 933篇 |
1979年 | 905篇 |
1978年 | 812篇 |
1977年 | 706篇 |
1976年 | 631篇 |
1975年 | 591篇 |
1973年 | 615篇 |
1972年 | 619篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
941.
Hardiljeet K. Boparai Meera Joseph Denis M. O’Carroll 《Environmental science and pollution research international》2013,20(9):6210-6221
Nano zerovalent iron (nZVI) is an effective remediant for removing various organic and inorganic pollutants from contaminated water sources. Batch experiments were conducted to characterize the nZVI surface and to investigate the effects of various solution properties such as pH, initial cadmium concentration, sorbent dosage, ionic strength, and competitive ions on cadmium removal by nZVI. Energy-dispersive X-ray and X-ray photoelectron spectroscopy results confirmed removal of Cd2+ ions by nZVI through adsorption. Cd2+ adsorption decreased in the presence of competitive cations in the order: Zn2+?>?Co2+?>?Mg2+?>?Mn2+?=?Cu2+?>?Ca2+?>?Na2+?=?K+. Higher concentrations of Cl? significantly decreased the adsorption. Cadmium removal increased with solution pH and reached a maximum at pH 8.0. The effects of various solution properties indicated Cd2+ adsorption on nZVI to be a chemisorption (inner-sphere complexation) process. The three surface complexation models (diffuse layer model, constant capacitance model, and triple layer model) fitted well to the adsorption edge experimental data indicating the formation of nZVI–Cd bidentate inner-sphere surface complexes. Our results suggest that nZVI can be effectively used for the removal of cadmium from contaminated water sources with varying chemical conditions. 相似文献
942.
X. Q. Liang Z. Y. Nie M. M. He R. Guo C. Y. Zhu Y. X. Chen Küppers Stephan 《Environmental science and pollution research international》2013,20(10):6972-6979
One strategy to combat nitrate (NO3-N) contamination in rivers is to understand its sources. NO3-N sources in the East Tiaoxi River of the Yangtze Delta Region were investigated by applying a 15N–18O dual isotope approach. Water samples were collected from the main channel and from the tributaries. Results show that high total N and NO3-N are present in both the main channel and the major tributaries, and NO3-N was one of the most important N forms in water. Analysis of isotopic compositions (δ 18O, δD) of water suggests that the river water mainly originated from three tributaries during the sampling period. There was a wide range of δ 15N-NO3 (?1.4 to 12.4 ‰) and a narrow range of δ 18O-NO3 (3.7 to 9.0 ‰) in the main channel waters. The δ 15N and δ 18O-NO3 values in the upper, middle, and lower channels along the river were shifted as 8.2, 3.5, and 9.5 ‰, and 9.0, 4.2, and 6.0 ‰, respectively. In the tributary South Tiao, the δ 15N and δ 18O-NO3 values were as high as 9.5 and 7.0 ‰, while in the tributaries Mid Tiao and North Tiao, NO3-N in most of the samples had relatively low δ 15N and δ 18O-NO3 values from 2.3 to 7.5 ‰ and 4.7 to 7.0 ‰, separately. Our results also suggest that the dual isotope approach can help us develop the best management practice for relieving NO3-N pollution in the rivers at the tributary scale. 相似文献
943.
Secondary pest outbreak is a counterintuitive ecological backlash of pesticide use in agriculture that takes place with the increase in abundance of a non-targeted pest species after pesticide application against a targeted pest species. Although the phenomenon was well recognized, its alternative causes are seldom considered. Outbreaks of the southern red mite Oligonychus ilicis are frequently reported in Brazilian coffee farms after the application of pyrethroid insecticides against the coffee leaf miner Leucoptera coffeella. Selectivity favoring the red mite against its main predatory mites is generally assumed as the outbreak cause, but this theory has never been tested. Here, we assessed the toxicity (and thus the selectivity) of deltamethrin against both mite species: the southern red mite and its phytoseid predator Amblyseius herbicolus. Additionally, behavioral avoidance and deltamethrin-induced hormesis were also tested as potential causes of red mite outbreak using free-choice behavioral walking bioassays with the predatory mite and life-table experiments with both mite species, respectively. Lethal toxicity bioassays indicated that the predatory mite was slightly more susceptible than its prey (1.5×), but in more robust demographic bioassays, the predator was three times more tolerant to deltamethrin than its prey, indicating that predator susceptibility to deltamethrin is not a cause of the reported outbreaks. The predator did not exhibit behavioral avoidance to deltamethrin; however insecticide-induced hormesis in the red mite led to its high population increase under low doses, which was not observed for the predatory mite. Therefore, deltamethrin-induced hormesis is a likely cause of the reported red mite outbreaks. 相似文献
944.
Nicresse L. Guedegba Ibrahim Imorou Toko Prudencio T. Agbohessi Berny’s Zoumenou Caroline Douny Syaghalirwa N.M. Mandiki 《Journal of environmental science and health. Part. B》2013,48(7):580-589
AbstractThis study aimed to compare the toxicity for fish of two active ingredients (lambda-cyhalothrin-20?g L?1, a pyrethroid, and acetamiprid-15?g L?1, a neonicotinoid) which are components of a commercial insecticide (Acer 35 EC) used in cotton crop in many West African countries. The juveniles of Oreochromis niloticus (4.01?±?0.34?g, mean body weight) were exposed for 96?h to increasing concentrations of active ingredients (lambda-cyhalothrin and acetamiprid) or a mixture similar to Acer 35 EC (composed by 20?g of chemical compound lambda-cyhalothrin and 15?g of acetamiprid dissolved in 1?L of acetone). The experiments were carried out under controlled conditions in aquaria according to OECD Guidelines. During the experiments, the behavioral responses (loss of balance, color change, hyperactivity, etc.) that usually precede death were observed in exposed fish. Mortalities were recorded in each aquarium and the LC50-96h of each chemical was determined. The LC50-96h obtained were respectively 0.1268, 0.0029, 182.9 and 0.5685?ppm for Acer 35 EC, lambda-cyhalothrin, acetamiprid and mixture. All insecticides used in this study had profound impact on Nile tilapia behavior which may confirm the neurotoxicity of each single active compound as well as of their mixture. 相似文献
945.
946.
947.
948.
949.
This Report, published as Informative Report No. 7 of the Air Pollution Control Association’s TI-5 Public Utilities Committee, began to move through the 14 step approval procedure of APCA’s Technical Council in February 1964 Comments made by members of the Technical Council were considered in the preparation of the final report. It is now published as representing the best thinking of the Association. It is an extremely timely and informative report. 相似文献
950.
C. C. Shale 《Journal of the Air & Waste Management Association (1995)》2013,63(3):159-160
Current-voltage relationships for negative corona are given for a pilot-scale electrostatic precipitator with 3-in. electrode spacing at 80°–1500°F and 35–80 psig. Direct comparison is made with the electrical characteristics for a 1-in. spacing at 1200°F over the same pressure range. Experimental results on both spacing agree well with electrostatic theory. Initial dust removal efficiencies for the pilot-scale precipitator ranged from 90 to 98% at 1460°F and 80 psig, but continuous operation was not achieved owing to excessive thermal expansion of the internal parts of the unit. 相似文献