全文获取类型
收费全文 | 284篇 |
免费 | 5篇 |
国内免费 | 2篇 |
专业分类
安全科学 | 31篇 |
废物处理 | 7篇 |
环保管理 | 83篇 |
综合类 | 40篇 |
基础理论 | 52篇 |
环境理论 | 1篇 |
污染及防治 | 55篇 |
评价与监测 | 14篇 |
社会与环境 | 5篇 |
灾害及防治 | 3篇 |
出版年
2023年 | 2篇 |
2022年 | 3篇 |
2021年 | 2篇 |
2020年 | 5篇 |
2019年 | 4篇 |
2018年 | 9篇 |
2017年 | 4篇 |
2016年 | 5篇 |
2015年 | 4篇 |
2014年 | 13篇 |
2013年 | 23篇 |
2012年 | 9篇 |
2011年 | 12篇 |
2010年 | 10篇 |
2009年 | 12篇 |
2008年 | 15篇 |
2007年 | 15篇 |
2006年 | 13篇 |
2005年 | 9篇 |
2004年 | 9篇 |
2003年 | 13篇 |
2002年 | 14篇 |
2001年 | 7篇 |
2000年 | 5篇 |
1999年 | 5篇 |
1998年 | 9篇 |
1997年 | 4篇 |
1996年 | 3篇 |
1995年 | 7篇 |
1994年 | 6篇 |
1993年 | 3篇 |
1992年 | 2篇 |
1991年 | 5篇 |
1990年 | 2篇 |
1989年 | 6篇 |
1988年 | 2篇 |
1987年 | 2篇 |
1986年 | 2篇 |
1985年 | 1篇 |
1984年 | 3篇 |
1982年 | 2篇 |
1981年 | 3篇 |
1980年 | 1篇 |
1973年 | 1篇 |
1972年 | 1篇 |
1966年 | 1篇 |
1923年 | 1篇 |
1919年 | 1篇 |
1916年 | 1篇 |
排序方式: 共有291条查询结果,搜索用时 531 毫秒
281.
Clausen C 《Waste management (New York, N.Y.)》2004,24(4):401-405
In this study, three possible improvements to a remediation process for chromated-copper-arsenate- (CCA) treated wood were evaluated. The process involves two steps: oxalic acid extraction of wood fiber followed by bacterial culture with Bacillus licheniformis CC01. The three potential improvements to the oxalic acid extraction step were (1) reusing oxalic acid for multiple extractions, (2) varying the ratio of oxalic acid to wood, and (3) using a noncommercial source of oxalic acid such as Aspergillus niger, which produces oxalic acid as a metabolic byproduct. Reusing oxalic acid for multiple extractions removed significant amounts of copper, chromium, and arsenic. Increasing the ratio of wood to acid caused a steady decline in metal removal. Aspergillus niger removed moderate amounts of copper, chromium, and arsenic from CCA-treated wood. Although A. niger was effective, culture medium costs are likely to offset any benefits. Repeated extraction with commercial oxalic acid appears to be the most cost-effective method tested for the two-step process. 相似文献
282.
283.
284.
All known cosmic and geological conditions and laws of chemistry and thermodynamics allow that complex organic matter could
have formed spontaneously on pristine planet Earth about 4,000 mya. Simple gasses and minerals on the surface and in oceans
of the early Earth reacted and were eventually organized in supramolecular aggregates and enveloped cells that evolved into
primitive forms of life. Chemical evolution, which preceded all species of extant organisms, is a fact. In this review, we
have concentrated on experimental and theoretical research published over the last two decades, which has added a wealth of
new details and helped to close gaps in our previous understanding of this multifaceted field. Recent exciting progress in
the molecular and genetic analyses of existing life, in particular microorganisms of ancient origin, even supports the possibility
that a cellular, self-reproducing common ancestor might be assembled and resurrected in anaerobic cultures at some time in
the future. Charles Darwin did not, and indeed, could not, address and specify the earliest phases of life which preceded
the Origin of Species. However, in a famous letter, he sketched “a warm little pond with all sorts of… (chemicals, in which) …a protein was chemically
formed.” We try to trace the impact of his charming clear-sighted metaphor up to the present time. 相似文献
285.
Jonathan M. Gallimore Barbara B. Brown Carol M. Werner 《Journal of environmental psychology》2011,31(2):184-191
We assessed environmental and perceptual correlates of walking and walkability for fifth graders from three communities attending two schools: A new urban/LEED-ND pilot community, mixed, and standard suburban community. Irvine-Minnesota Inventory (IMI) walkability audits showed that new urban blocks provided more traffic safety, pleasurability, crime safety, density, and diversity. New urban routes offered greater traffic safety, accessibility, pleasurability, crime safety, and diversity, but suburban routes had greater housing density, net of controls (parental education, rooms in the home, home ownership, parent preference for child to walk to school). Parents and children perceived new urban routes to be more walkable and children walked more when they lived on more walkable routes. The suburban hierarchical street design exposed children to varied traffic safety conditions by funneling their walks from cul-de-sacs to arterials. The new urban routes to a centrally located school passed by pleasant open spaces, suggesting how community organization can create better walking conditions. 相似文献
286.
Phosphorus (P) in rivers in the Mississippi River basin (MRB) contributes to hypoxia in the Gulf of Mexico and impairs local water quality. We analyzed the spatial pattern of P in the MRB to determine the counties with the greatest January to June P riverine yields and the most critical factors related to this P loss. Using a database of P inputs and landscape characteristics from 1997 through 2006 for each county in the MRB, we created regression models relating riverine total P (TP), dissolved reactive P (DRP), and particulate P (PP) yields for watersheds within the MRB to these factors. Riverine yields of P were estimated from the average concentration of each form of P during January to June for the 10-yr period, multiplied by the average daily flow, and then summed for the 6-mo period. The fraction of land planted in crops, human consumption of P, and precipitation were found to best predict TP yields with a spatial error regression model ( = 0.48, = 101). Dissolved reactive P yields were predicted by fertilizer P inputs, human consumption of P, and precipitation in a multiple regression model ( = 0.42, = 73), whereas PP yields were explained by crop fraction, human consumption of P, and soil bulk density in a spatial error regression model ( = 0.49, = 61). Overall, the Upper Midwest's Cornbelt region and lower Mississippi basin had the counties with the greatest P yields. These results help to point out specific areas where agricultural conservation practices that reduce losses to streams and rivers and point source P removal might limit the intensity or spatial occurrence of Gulf of Mexico hypoxia and improve local water quality. 相似文献
287.
288.
Will Allen Shaun Ogilvie Helen Blackie Des Smith Shona Sam James Doherty Don McKenzie James Ataria Lee Shapiro Jamie MacKay Elaine Murphy Chris Jacobson Charles Eason 《Environmental management》2014,53(2):429-440
The success of research in integrated environmental and natural resource management relies on the participation and involvement of different disciplines and stakeholders. This can be difficult to achieve in practice because many initiatives fail to address the underlying social processes required for successful engagement and social learning. We used an action research approach to support a research-based group with a range of disciplinary and stakeholder expertise to critically reflect on their engagement practice and identify lessons around how to collaborate more effectively. This approach is provided here as a guide that can be used to support reflective research practice for engagement in other integration-based initiatives. This paper is set in the context of an integrated wildlife management research case study in New Zealand. We illustrate how multi-, inter- and trans-disciplinary approaches can provide a framework for considering the different conversations that need to occur in an integrated research program. We then outline rubrics that list the criteria required in inter- and trans-disciplinary collaborations, along with examples of effective engagement processes that directly support integration through such efforts. Finally, we discuss the implications of these experiences for other researchers and managers seeking to improve engagement and collaboration in integrated science, management and policy initiatives. Our experiences reaffirm the need for those involved in integrative initiatives to attend to the processes of engagement in both formal and informal settings, to provide opportunities for critical reflective practice, and to look for measures of success that acknowledge the importance of effective social process. 相似文献
289.
Watercraft collisions account for 25–30% of manatee deaths annually in Florida. Education and outreach interventions for boaters
are strategies for reducing manatee mortality. We evaluated the effectiveness of the Manatee Watch program by surveying primary
boat users whose boats were approached by Manatee Watch. We compared the attitudes, knowledge, and behavioral intentions of
boaters who received Manatee Watch materials with a control group of boaters observed by the Florida Marine Research Institute
in Tampa Bay during 1999–2001. Results of the 51-item telephone survey with 499 boaters indicated that the Manatee Watch intervention
had little effect on boater’s attitudes, knowledge, and behaviors regarding manatees. However, individual attitude scores
were positively correlated with safe boating behaviors in shallow waters including maintaining a slower speed and watching
out for manatees. Overall knowledge about manatees was correlated with one manatee-safe boating behavior. To improve efficacy,
educators should (a) incorporate evaluation into the planning stages of program development; (b) target messages to influence
boaters’ attitudes toward manatees and ecosystem health, and their feelings of ownership and empowerment; (c) facilitate active
participation of the boaters; and (d) increase the duration and variety of intervention. 相似文献
290.
LeDuc DL AbdelSamie M Móntes-Bayon M Wu CP Reisinger SJ Terry N 《Environmental pollution (Barking, Essex : 1987)》2006,144(1):70-76
A major goal of our selenium (Se) phytoremediation research is to use genetic engineering to develop fast-growing plants with an increased ability to tolerate, accumulate, and volatilize Se. To this end we incorporated a gene (encoding selenocysteine methyltransferase, SMT) from the Se hyperaccumulator, Astragalus bisulcatus, into Indian mustard (LeDuc, D.L., Tarun, A.S., Montes-Bayón, M., Meija, J., Malit, M.F., Wu, C.P., AbdelSamie, M., Chiang, C.-Y., Tagmount, A., deSouza, M., Neuhierl, B., B?ck, A., Caruso, J., Terry, N., 2004. Overexpression of selenocysteine methyltransferase in Arabidopsis and Indian mustard increases selenium tolerance and accumulation Plant Physiol. 135, 377-383.). The resulting transgenic plants successfully enhanced Se phytoremediation in that the plants tolerated and accumulated Se from selenite significantly better than wild type. However, the advantage conferred by the SMT enzyme was much less when Se was supplied as selenate. In order to enhance the phytoremediation of selenate, we developed double transgenic plants that overexpressed the gene encoding ATP sulfurylase (APS) in addition to SMT, i.e., APSxSMT. The results showed that there was a substantial improvement in Se accumulation from selenate (4 to 9 times increase) in transgenic plants overexpressing both APS and SMT. 相似文献