全文获取类型
收费全文 | 2548篇 |
免费 | 74篇 |
国内免费 | 24篇 |
专业分类
安全科学 | 181篇 |
废物处理 | 151篇 |
环保管理 | 541篇 |
综合类 | 298篇 |
基础理论 | 586篇 |
环境理论 | 3篇 |
污染及防治 | 580篇 |
评价与监测 | 179篇 |
社会与环境 | 92篇 |
灾害及防治 | 35篇 |
出版年
2023年 | 11篇 |
2022年 | 19篇 |
2021年 | 27篇 |
2020年 | 26篇 |
2019年 | 26篇 |
2018年 | 61篇 |
2017年 | 58篇 |
2016年 | 76篇 |
2015年 | 72篇 |
2014年 | 70篇 |
2013年 | 231篇 |
2012年 | 108篇 |
2011年 | 148篇 |
2010年 | 114篇 |
2009年 | 131篇 |
2008年 | 127篇 |
2007年 | 143篇 |
2006年 | 133篇 |
2005年 | 97篇 |
2004年 | 85篇 |
2003年 | 107篇 |
2002年 | 71篇 |
2001年 | 54篇 |
2000年 | 53篇 |
1999年 | 41篇 |
1998年 | 39篇 |
1997年 | 34篇 |
1996年 | 33篇 |
1995年 | 26篇 |
1994年 | 34篇 |
1993年 | 31篇 |
1992年 | 21篇 |
1991年 | 24篇 |
1990年 | 13篇 |
1989年 | 11篇 |
1988年 | 16篇 |
1987年 | 19篇 |
1986年 | 13篇 |
1985年 | 19篇 |
1984年 | 12篇 |
1983年 | 18篇 |
1982年 | 19篇 |
1981年 | 24篇 |
1980年 | 13篇 |
1979年 | 10篇 |
1978年 | 6篇 |
1977年 | 9篇 |
1971年 | 6篇 |
1957年 | 5篇 |
1955年 | 5篇 |
排序方式: 共有2646条查询结果,搜索用时 156 毫秒
311.
Spencer HB Hussein WR Tchounwou PB 《Journal of environmental biology / Academy of Environmental Biology, India》2006,27(1):1-5
A recent study in our laboratory has demonstrated that tetrachloroethylene (TCE) is acutely toxic to Japanese medaka (Oryzias latipes) larvae with a 96 hr-LC50 of 18 (17-19) mg/mL (Spencer et al., 2002). In the present study we hypothesize that TCE exposure induces a developmental effect in Japanese medaka. Growth and age specific sensitivity of Japanese medaka larvae were studied with four age groups (7, 14, 21 and 28 days old) to determine tetrachloroethylene effects on these parameters. The medaka larvae were exposed for 96 hours in a single concentration (10 mg/mL) of TCE. The toxic endpoints evaluated were larvae weight, length, water content and protein concentration. The study revealed that exposure of medaka larvae to this sub-acute concentration of TCE significantly reduced length and weight in the treated group. The difference in growth between control and treated groups was more obvious in age versus length, than in age versus weight. The dry weight-fresh weight ratio (dw/fw) was shown to be higher in the control group. Water content in TCE-treated medaka was higher than in the control group, and younger fry had more water content than older ones. A higher protein concentration was also observed in TCE-treated medaka compared to the control group. These results indicate that TCE has a profound effect on the growth and development of Japanese medaka larvae. 相似文献
312.
INTRODUCTION: Using data from the NASS General Estimates System (GES), the method of induced exposure was used to assess the effects of electronic stability control (ESC) on loss-of-control type crashes for sport utility vehicles. METHOD: Sport utility vehicles were classified into crash types generally associated with loss of control and crash types most likely not associated with loss of control. Vehicles were then compared as to whether ESC technology was present or absent in the vehicles. A generalized additive model was fit to assess the effects of ESC, driver age, and driver gender on the odds of loss of control. In addition, the effects of ESC on roads that were not dry were compared to effects on roads that were dry. RESULTS: Overall, the estimated percentage reduction in the odds of a loss-of-control crash for sport utility vehicles equipped with ESC was 70.3%. Both genders and all age groups showed reduced odds of loss-of-control crashes, but there was no significant difference between males and females. With respect to driver age, the maximum percentage reduction of 73.6% occurred at age 27. The positive effects of ESC on roads that were not dry were significantly greater than on roads that were dry. 相似文献
313.
Hung CL Xu Y Lam JC Jefferson TA Hung SK Yeung LW Lam MH O'Toole DK Lam PK 《Chemosphere》2006,63(5):845-852
The risks to Indo-Pacific Humpback Dolphins and Finless Porpoises associated with polychlorinated biphenyls (PCBs) were assessed. Stomach contents from twelve stranded Humpback Dolphins and sixteen stranded Finless Porpoises were collected. Concentrations of total and isomer-specific PCBs in the stomach contents were determined using dual-column gas chromatography equipped with electron capture detectors (GC-ECD). Risks due to the PCBs were assessed in three scenarios, based on total PCBs (summation of 41 PCB congeners), total toxicity equivalency (TEQs) and PCB 118, using the toxicity reference values (TRVs) as the threshold effects benchmarks. The calculated risk quotients (RQs) showed that risks due to PCBs were generally low or negligible. Specifically, RQs from total TEQs and total PCBs for Finless Porpoises are below one, suggesting that PCBs should be a low risk for the Finless Porpoise in Hong Kong waters. However, the Humpback Dolphin has RQs larger than 1 for total TEQs and total PCBs when the 95th percentile data were used in the evaluation. This indicates that further investigation may be needed to examine more closely the potential impact of toxic contaminants in the habitat of the Humpback Dolphin. 相似文献
314.
315.
Covaci A Gheorghe A Hulea O Schepens P 《Environmental pollution (Barking, Essex : 1987)》2006,140(1):136-149
Concentrations of polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and organochlorine pesticides (OCPs), such as dichlorodiphenyltrichloroethane (DDT) and analogues, hexachlorocyclohexanes (HCHs) and hexachlorobenzene (HCB), were measured in sediments and biota (invertebrates, 11 fish species and cormorant tissues) collected in 2001 from the Danube Delta, the biggest European wetland. DDTs were the predominant pollutants in all samples. A high variability in the concentrations of pollutants within the same species was observed and this was related to sampling location, age, length and sex. DDTs were also the main organohalogenated contaminants in cormorant muscle and liver, followed by PCBs, HCHs, HCB and PBDEs. The present levels of DDTs in cormorant tissues are lower than levels measured in cormorant eggs sampled from the Danube Delta in 1982 and 1997, respectively. The variance of delta15N for herbivores was much greater than for carnivores, while carp and bream showed higher delta15N signatures than expected, probably due to a higher dietary proportion of benthos, typically more delta15N enriched relative to pelagic biota. 相似文献
316.
Heckmann LH Griffiths BS Caul S Thompson J Pusztai-Carey M Moar WJ Andersen MN Krogh PH 《Environmental pollution (Barking, Essex : 1987)》2006,142(2):212-216
Studies on the effect of genetically modified Bacillus thuringiensis (Bt) crops on true soil dwelling non-target arthropods are scarce. The objective of this study was to assess the influence of a 4-week exposure to two Bt maize varieties (Cry1Ab) Cascade and MEB307 on the collembolan Protaphorura armata. For comparison three non-Bt maize varieties, Rivaldo (isogenic to Cascade), Monumental (isogenic to MEB307) and DK242, and two control diets based on baker's yeast (uncontaminated and contaminated with Bt toxin Cry1Ab) were also tested. Due to a lower C:N ratio, individuals reared on yeast performed significantly better in all of the measured endpoints than those reared on maize. P. armata performed equally well when reared on two Bt and three non-Bt maize varieties. Although there were no negative effects of Bt maize in this experiment, we recommend future studies on Bt crops to focus on species interactions in long-term, multi-species experiments. 相似文献
317.
Lam JC Tanabe S Chan SK Lam MH Martin M Lam PK 《Environmental pollution (Barking, Essex : 1987)》2006,144(3):790-801
Concentrations of 22 trace elements were determined in green turtle (Chelonia mydas) eggs collected from Hong Kong. Concentrations of selenium, lead and nickel in these eggs were generally higher than those reported in other studies. The predicted no effect concentrations (PNEC; ng/g wet weight) of Pb (1000), Se (340 and 6000 for the worst-case and best-case scenarios, respectively) and Ni (17) in the green turtle eggs were estimated. Hazard quotients (HQs) estimate that Se (HQs: 0.2-24.5) and Ni (HQs: 4.0-26.4) may pose some risks to the turtles. Our study also found that concentrations of Ag, Se, Zn, Hg and Pb in the shell of the turtle eggs were significantly correlated with levels in the whole egg contents (yolk+albumen). Once the precise relationships of specific elements are established, egg-shell concentrations may be used as a non-lethal, non-invasive, surrogate for predicting whole egg burden of certain contaminants in marine turtles. 相似文献
318.
Jennifer Butters Robert E. Mann Christine M. Wickens Paul Boase 《Journal of Safety Research》2012,43(5-6):405-411
IntroductionDriving safety, impaired driving, and legislation to address these concerns remain important issues. It is imperative countermeasures be targeted toward the most appropriate groups. This paper explores the potential relationship between gender and driving attitudes toward safety issues and impaired-driving countermeasures.MethodThe data are from the 2007 Impaired Driving Survey commissioned by Transport Canada and Mothers Against Drunk Driving (MADD) Canada. The survey is a, stratified by region, telephone survey of 1,514 Canadian drivers 18 years of age and older with a valid driver's license who had driven within the past 30 days.ResultsThe findings illustrate a consistent impact of gender on these issues. Other variables were also identified as relevant factors although less consistently. Current findings suggest that strategies for building support for interventions, or for changing risk perception/concern for risky driving behaviors should be tailored by gender to maximize the potential for behavior change.ImpactThis information may assist program and policy developers through the identification of more or less receptive target groups. Future research directions are also presented. 相似文献
319.
320.
Mimi H. Hassim Markku Hurme Paul R. Amyotte Faisal I. Khan 《Journal of Loss Prevention in the Process Industries》2012,25(5):820-829
Fugitive emissions are among the major concerns of industrial process releases. The emissions cause problem to various aspects including the environment, health, and economic. Early evaluation of process hazards is beneficial because process can be made inherently benign at lower cost. This paper discusses two important aspects of fugitive emissions assessment during process design – the quantification and the prevention strategies.For the quantification part, three methods are presented for fugitive emissions estimation during the process design. They are tailored to data available in simple process flow diagram (PFD), detailed PFD, and piping & instrumentation diagram (PID). Such methods are needed as early emissions estimation allows production routes and process designs with lower emissions to be selected. The fugitive emissions estimation and methods to abatement are demonstrated on a benzene process case study. Valves are found to be the major emission source with 50% of fugitive emissions of process area in a base case of petrochemical process, in which no fugitive emission reductions are yet made. Pumps without mechanical seals come second with 30% and flanges with 8% of emissions. Inherently safer design keywords can be applied to prevent fugitive emissions in the process plants. Substitution is the most applicable keyword in fugitive emission reduction of existing plants.The emission rate calculations together with estimation of health risk give a sound background for the decision making on elimination of emissions at source through equipment and piping changes. The case study presented reveals that by substituting emission prone components by inherently low-leaking ones, the plant emissions can be reduced over 90% in practice. This is created mainly by replacing rising stem valves with ball valves, installing double mechanical pump seals or hermetic pumps and making changes in sampling and relief systems. Ideally by also changing flanges to welded connections, which is not viable for various reasons, the emissions could be reduced nearly to zero. 相似文献