全文获取类型
收费全文 | 27091篇 |
免费 | 228篇 |
国内免费 | 169篇 |
专业分类
安全科学 | 597篇 |
废物处理 | 1158篇 |
环保管理 | 2781篇 |
综合类 | 5215篇 |
基础理论 | 6180篇 |
环境理论 | 15篇 |
污染及防治 | 7228篇 |
评价与监测 | 1942篇 |
社会与环境 | 2280篇 |
灾害及防治 | 92篇 |
出版年
2022年 | 332篇 |
2021年 | 361篇 |
2020年 | 180篇 |
2019年 | 257篇 |
2018年 | 519篇 |
2017年 | 543篇 |
2016年 | 755篇 |
2015年 | 524篇 |
2014年 | 838篇 |
2013年 | 2023篇 |
2012年 | 968篇 |
2011年 | 1262篇 |
2010年 | 935篇 |
2009年 | 995篇 |
2008年 | 1238篇 |
2007年 | 1277篇 |
2006年 | 1078篇 |
2005年 | 907篇 |
2004年 | 913篇 |
2003年 | 858篇 |
2002年 | 775篇 |
2001年 | 907篇 |
2000年 | 590篇 |
1999年 | 412篇 |
1998年 | 268篇 |
1997年 | 278篇 |
1996年 | 291篇 |
1995年 | 330篇 |
1994年 | 310篇 |
1993年 | 272篇 |
1992年 | 262篇 |
1991年 | 262篇 |
1990年 | 272篇 |
1989年 | 226篇 |
1988年 | 217篇 |
1987年 | 197篇 |
1986年 | 211篇 |
1985年 | 198篇 |
1984年 | 219篇 |
1983年 | 209篇 |
1982年 | 231篇 |
1981年 | 183篇 |
1980年 | 187篇 |
1979年 | 171篇 |
1978年 | 167篇 |
1977年 | 145篇 |
1976年 | 130篇 |
1975年 | 140篇 |
1974年 | 143篇 |
1972年 | 128篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
Estimating Remediation and Contaminant Respiration Emissions for Alternatives Comparisons at Petroleum Spill Sites 下载免费PDF全文
Greenhouse gas emissions assessments for site cleanups typically quantify emissions associated with remediation and not those from contaminant biodegradation. Yet, at petroleum spill sites, these emissions can be significant, and some remedial actions can decrease this additional component of the environmental footprint. This article demonstrates an emissions assessment for a hypothetical site, using the following technologies as examples: excavation with disposal to a landfill, light nonaqueous‐phase liquid (LNAPL) recovery with and without recovered product recycling, passive bioventing, and monitored natural attenuation (MNA). While the emissions associated with remediation for LNAPL recovery are greater than the other considered alternatives, this technology is comparable to excavation when a credit associated with product recycling is counted. Passive bioventing, a green remedial alternative, has greater remedial emissions than MNA, but unlike MNA can decrease contaminant‐related emissions by converting subsurface methane to carbon dioxide. For the presented example, passive bioventing has the lowest total emissions of all technologies considered. This illustrates the value in estimating both remediation and contaminant respiration emissions for petroleum spill sites, so that the benefit of green remedial approaches can be quantified at the remedial alternatives selection stage rather than simply as best management practices. ©2015 Wiley Periodicals, Inc. 相似文献
22.
Goettems-Fiorin Pauline Brendler Costa-Beber Lilian Corrêa dos Santos Jaíne Borges Friske Paula Taís Sulzbacher Lucas Machado Frizzo Matias Nunes Ludwig Mirna Stela Rhoden Cláudia Ramos Heck Thiago Gomes 《Environmental science and pollution research international》2019,26(20):20581-20594
Environmental Science and Pollution Research - The reduction of estrogen levels, as a result of menopause, is associated with the development of metabolic diseases caused by alterations in... 相似文献
23.
V. Vijayasree Hebsy Bai S. Naseema Beevi Thomas Biju Mathew Thomas George George Xavier 《Environmental monitoring and assessment》2015,187(5):299
Dissipation and decontamination of chlorantraniliprole (Coragen 18.5 SC) in brinjal and okra fruits were studied following field application at single and double doses of 30 and 60 g ai ha?1, and the residues of the insecticide was estimated using LC-MS/MS. Initial residues of chlorantraniliprole at single and double doses on the fruits of brinjal were 0.72 and 1.48 mg kg?1, while on okra fruits, the residues were 0.48 and 0.91 mg kg?1, respectively. The residues reached below detectable level of 0.01 mg kg?1 on the 10th day. Half-life of chlorantraniliprole at 30 and 60 g ai ha?1 on brinjal was 1.58 and 1.80 days with the calculated waiting period of 0.69 and 2.38 days, whereas on okra, the values were 1.60 and 1.70 and 0 and 1.20 days, respectively. The extent of removal of chlorantraniliprole using simple decontaminating techniques at 2 h and 3 days after spraying was 40.99–91.37 % and 29.85–89.12 %, respectively, from brinjal fruits and 47.78–86.10 % and 41.77–86.48 %, respectively, from okra fruits. 相似文献
24.
Maheswari C. Ramya A. S. Priya B. Meenakshi Sudhahar S. Prabhu Raj B. Lokesh B. Ramani G. 《Journal of Material Cycles and Waste Management》2021,23(6):2255-2265
Journal of Material Cycles and Waste Management - The present research work focused on fabricating Biodegradable Plate (BD plate) composed of rice husk ash, bagasse and corn starch which is... 相似文献
25.
The effects of Cu2+, Cd2+, and Ni2+ at low and high concentrations (0.025 and 0.25 mg/ml) on the accumulation capacity, the state of the pigment complex, and photosynthesis rate have been studied in model experiments with three floating hydrophytes (Hydrocharis morsus-ranae L., Lemna gibba L., and Potamogeton natans L.) and four submerged hydrophytes (Elodea canadensis Michx., Lemna trisulka L., Ceratophyllum demersum L., and Potamogeton lucens L.). Copper and cadmium are especially toxic at the concentrations studied. The effect of Cu2+ was the strongest in hydatophytes, and the effect of Cd2+, in pleustophytes. It is hypothesized that the differences between hydrophytes with respect to accumulation of metals and decrease in photosynthesis rate may cause predominant elimination of submerged species. Therefore, changes in the species structure of hydrophyte communities may be expected in waters polluted with metals. 相似文献
26.
Quantitative methods have been applied to the study of floristic structure and diversity in Samarskaya Luka. The results show that Samarskaya Luka is a floristically heterogeneous area in which six elementary floras can be distinguished. This area has been assessed as a floristically autonomous formation, and its floristic representativeness was estimated. 相似文献
27.
F. Pricope Ştefănescu G. Tiţescu I. Cărăuş D. Ureche 《Environmental Chemistry Letters》2003,1(2):149-151
During the artificial reproduction of salmonides, the fecundity can be increased either by improving the viability of spermatozoa,
or by extending the time period during which a roe micropile remains open, thus allowing its fecundation. Practically, this
can be achieved by the use of some fertilising techniques suitable for fish species. Here, we show that the reproduction of
rainbow trout in a 1:1 solution of deuterium-depleted water and distilled water led to a significant increase in survival
of roes during their embryonic development. Moreover, the addition of glucose and fructose into the deuterium-depleted fertilising
solutions led to a further increase in roe survival during embryonic development. The increase in survival is mainly explained
by an increase in the motility of spermatozoa. 相似文献
28.
G G Pyle S M Swanson D M Lehmkuhl 《Environmental pollution (Barking, Essex : 1987)》2002,116(2):243-255
Elevated concentrations of arsenic, nickel, and molybdenum in aquatic systems around northern Saskatchewan uranium mines are an environmental concern. Early life stage fathead minnows were used to assess toxicity from several aquatic systems near the Key Lake and Rabbit Lake uranium operations. Hatching success of fish embryos exposed to waters receiving contaminants associated with uranium ore milling was reduced by 32-61% relative to controls. Mortality differed in two lakes receiving mill effluents because of opposing factors influencing metal toxicity (i.e. low pH and high hardness). In one mill receiving water (Fox Lake), larval mortality was 0%, whereas mortality was 85% in water collected from a downstream location (Unknown Lake). Fish embryos exposed to open-pit dewatering effluent receiving waters, or water from a flooded open pit (i.e. pit waters), hatched 26-39% earlier than those exposed to reference or control water. The combination of low water hardness and elevated nickel concentrations in pit waters contributed to the early hatching. Egg hatchability and hatching time were more sensitive indicators of toxicity than 'standard' endpoints, like larval mortality and growth. Current regulatory emphasis on single contaminants and standard toxicological endpoints should be re-evaluated in light of the complex interaction among confounding variables such as pH, hardness. conductivity, and multi-metal mixtures. 相似文献
29.
30.
I Chu D C Villeneuve B McDonald V E Secours V E Valli 《Journal of environmental science and health. Part. B》1987,22(3):303-317
Pentachlorotoluene (PCT) and pentabromotoluene (PBT) are environmental contaminants detected in the Great Lakes ecosystem. In view of the paucity of toxicity data and the potential for human exposure, a subacute (28 day) and a subchronic (91 day) study were conducted in the rat. In the subacute study, groups of 10 male and 10 female rats were fed the diet containing PCT or PBT at 0, 0.5, 5.0, 50 or 500 ppm for 28-days. In the subchronic study, the group size was increased to 15, the dose levels were 0, 0.05, 0.5, 5.0, 50 and 500 ppm in the diet and the exposure period was 91 days. Growth rate and food consumption were not affected by exposure to either chemical in the subacute and subchronic study. Clinical observations revealed no abnormalities. Decreased hemoglobin was observed in female rats fed 5.0 ppm PCT and higher levels in the subacute (28 day) study. In the same study the hematocrit value and erythrocyte numbers of females fed 5.0 or 500 ppm PCT diets were significantly lower than the control. In both subacute and subchronic studies mild dose-dependent histopathological changes were observed in the thyroid, liver and kidney of rats fed PCT and PBT diets. In general male rats were more susceptible than females to the treatment of PCT and PBT. Based on these data, it was concluded that the no observable adverse effect level for PCT was 50 ppm in the diet (3.5 mg/kg b.w./day) and that of PBT was 5.0 ppm (0.35 mg/kg b.w./day). 相似文献