全文获取类型
收费全文 | 245篇 |
免费 | 0篇 |
专业分类
安全科学 | 5篇 |
废物处理 | 3篇 |
环保管理 | 6篇 |
综合类 | 150篇 |
基础理论 | 22篇 |
污染及防治 | 49篇 |
评价与监测 | 6篇 |
社会与环境 | 4篇 |
出版年
2014年 | 3篇 |
2013年 | 10篇 |
2012年 | 4篇 |
2011年 | 3篇 |
2010年 | 3篇 |
2009年 | 6篇 |
2008年 | 9篇 |
2007年 | 12篇 |
2006年 | 6篇 |
2004年 | 4篇 |
2003年 | 4篇 |
2002年 | 5篇 |
2000年 | 2篇 |
1999年 | 3篇 |
1994年 | 2篇 |
1993年 | 2篇 |
1992年 | 2篇 |
1984年 | 2篇 |
1979年 | 5篇 |
1978年 | 7篇 |
1976年 | 2篇 |
1969年 | 3篇 |
1966年 | 7篇 |
1965年 | 3篇 |
1964年 | 8篇 |
1963年 | 8篇 |
1962年 | 4篇 |
1961年 | 9篇 |
1960年 | 3篇 |
1959年 | 3篇 |
1958年 | 6篇 |
1957年 | 6篇 |
1956年 | 9篇 |
1955年 | 4篇 |
1954年 | 7篇 |
1953年 | 6篇 |
1952年 | 4篇 |
1951年 | 3篇 |
1950年 | 2篇 |
1947年 | 3篇 |
1941年 | 2篇 |
1939年 | 2篇 |
1932年 | 2篇 |
1931年 | 3篇 |
1930年 | 2篇 |
1926年 | 2篇 |
1922年 | 2篇 |
1917年 | 2篇 |
1914年 | 4篇 |
1913年 | 3篇 |
排序方式: 共有245条查询结果,搜索用时 15 毫秒
201.
Haluk Ozkaynak Arthur D. Schatz George D. Thurston Ronald G. Isaacs Rudolf B. Husar 《Journal of the Air & Waste Management Association (1995)》2013,63(11):1176-1185
Epidemiological assessments of population exposures to airborne particles are often hampered by the scarcity of available fine particle mass measurements. In an attempt to overcome this serious problem, we analyze In this paper methods for predicting fine particle (M 1) and Inhalable particle (IP) mass concentrations using relative humidity corrected light extinction coefficient (b ext) estimated from airport visual range (V r) observations. The analyses presented are based on theoretical determinations as well as statistical investigations utilizing EPA's NASN and Inhalable Particle Monitoring Network (IPMN) data bases and routine airport visual range observations In twelve large U.S. cities. Our results Indicate that, after controlling for certain limitations of airport visual range data, most of the regression models developed in this paper can be applied satisfactorily to predict M t and IP. Furthermore, our findings Indicate that a more representative formula than the commonly used meteorological range formula to predict atmospheric b ext values in urban areas may be b ext = (1.8 ± 0.04)/V r. Because of known local or regional influences, however, we do suggest calibration of any predictive model which utilizes airport visibility data against site-specific aerometric data on particle mass concentrations or scattering coefficient measurements. 相似文献
202.
Contributions of humic substances to the dissolved organic carbon pool in wetlands from different climates 总被引:1,自引:0,他引:1
Wetlands are an important source of DOM. However, the quantity and quality of wetlands' DOM from various climatic regions have not been studied comprehensively. The relationship between the concentrations of DOM (DOC), humic substances (HS) and non-humic substances (NHS) in wetland associated sloughs, streams and rivers, in cool temperate (Hokkaido, Japan), sub-tropical (Florida, USA), and tropical (Sarawak, Malaysia) regions was investigated. The DOC ranged from 1.0 to 15.6 mg CL(-1) in Hokkaido, 6.0-24.4 mg CL(-1) in Florida, and 18.9-75.3 mg CL(-1) in Sarawak, respectively. The relationship between DOC and HS concentrations for the whole sample set was regressed to a primary function with y-intercept of zero (P<0.005) and a slope value of 0.841. A similar correlation was observed between DOC and NHS concentrations, with a smaller slope value of 0.159. However, the correlation coefficient of the latter was much larger when the data was regressed to a logarithmic curve. These observations suggest the presence of a general tendency that the increased DOC in the river waters was mainly due to the increased supply of HS from wetland soils, whereas the rate of the increase in the NHS supply has an upper limit which may be controlled by primary productivity. 相似文献
203.
In dominantly kaolinite-type, natural clay minerals, we found PCDDs at considerable levels (TEQ-values up to several hundred ng/kg). Contrary to expectations, PCDFs were not detected at all. The PCDD-contamination is most likely “natural” and not of anthropogenic origin. 相似文献
204.
205.
Assessing Landscape Functions with Broad-Scale Environmental Data: Insights Gained from a Prototype Development for Europe 总被引:4,自引:0,他引:4
Felix Kienast Janine Bolliger Marion Potschin Rudolf S. de Groot Peter H. Verburg Iris Heller Dirk Wascher Roy Haines-Young 《Environmental management》2009,44(6):1099-1120
We examine the advantages and disadvantages of a methodological framework designed to analyze the poorly understood relationships
between the ecosystem properties of large portions of land, and their capacities (stocks) to provide goods and services (flows).
These capacities (stocks) are referred to as landscape functions. The core of our assessment is a set of expert- and literature-driven
binary links, expressing whether specific land uses or other environmental properties have a supportive or neutral role for
given landscape functions. The binary links were applied to the environmental properties of 581 administrative units of Europe
with widely differing environmental conditions and this resulted in a spatially explicit landscape function assessment. To
check under what circumstances the binary links are able to replace complex interrelations, we compared the landscape function
maps with independently generated continent-wide assessments (maps of ecosystem services or environmental parameters/indicators).
This rigorous testing revealed that for 9 out of 15 functions the straightforward binary links work satisfactorily and generate
plausible geographical patterns. This conclusion holds primarily for production functions. The sensitivity of the nine landscape
functions to changes in land use was assessed with four land use scenarios (IPCC SRES). It was found that most European regions
maintain their capacity to provide the selected services under any of the four scenarios, although in some cases at other
locations within the region. At the proposed continental scale, the selected input parameters are thus valid proxies which
can be used to assess the mid-term potential of landscapes to provide goods and services. 相似文献
206.
Polybrominated diphenyl ethers and organochlorine pesticides in human breast milk from Massachusetts, USA 总被引:2,自引:0,他引:2
Johnson-Restrepo B Addink R Wong C Arcaro K Kannan K 《Journal of environmental monitoring : JEM》2007,9(11):1205-1212
Concentrations of polybrominated diphenyl ethers (PBDEs), and organochlorine pesticides (OCPs; DDTs, HCHs, CHLs, and HCB) were measured in human breast milk samples collected across Massachusetts, USA, in 2004. Seventeen PBDE congeners were found in the samples, ranging in concentration from 0.06 to 1910 ng g(-1) lipid wt. BDE-47 (2,2',4,4'-tetraBDE), BDE-99 (2,2',4,4',5-pentaBDE), and BDE-100 (2,2',4,4',6-pentaBDE) were the major congeners detected in breast milk samples. Overall mean (+/-SD) concentrations of DDTs, HCHs, CHLs, and HCB were 64.5 +/- 75, 18.9 +/- 19, 32.4 +/- 36, and 2.3 +/- 2.2 ng g(-1) lipid wt, respectively. Concentrations of PBDEs were strongly correlated with concentrations of OCPs in the samples. Based on the concentrations of organohalogens and the intake rates of breast milk by infants in the United States, daily ingestion rates of contaminants were calculated. The median ingestion rates for PBDEs, HCHs, DDTs, CHLs, and HCB were 4.0, 212, 141, 44, and 5.79 ng kg(-1) body wt day(-1), respectively. The estimated daily intake of organohalogens by infants was compared with threshold reference values suggested by the United States Environmental Protection Agency (USEPA) and the Agency for Toxic Substances and Disease Registry (ATSDR), for calculation of hazard quotients (HQs). HQs for individual organohalogens and the sum of HQ for all organohalogens were calculated as HQ indices (HQI). The results suggest that one or more of the contaminants analyzed in this study exceeded the threshold reference values in at least 26% of the breast milk samples. 相似文献
207.
Occurrence and distribution of novel botryococcene hydrocarbons in freshwater wetlands of the Florida Everglades 总被引:1,自引:0,他引:1
A high abundance of isoprenoid hydrocarbons, the botryococcenes, with carbon numbers from 32 to 34 were detected in the Florida Everglades freshwater wetlands. These compounds were present in varying amounts up to 106microg/gdw in periphyton, 278microg/gdw in floc, and 46microg/gdw in soils. Their structures were determined based on comparison to standards, interpretation of their mass spectra and those of their hydrogenation products, and comparison of Kovats indexes to those reported in the literature. A total of 26 cyclic and acyclic botryococcenes with 8 skeletons were identified, including those with fewer degrees of unsaturation, which are proposed as early diagenetic derivatives from the natural products. This is the first report that botryococcenes occur in the Everglades freshwater wetlands. Their potential biogenetic sources from green algae and cyanobacteria were examined, but neither contained botryococcenes. Thus, the source implication of botryococcenes in this ecosystem needs further study. 相似文献
208.
209.
In recent years, there has been a boom in environmental assessment reports utilizing environmental indicators. Most of these
publications are based on the casual chain frameworks (e.g., Pressure–State–Response (PSR), Driving force–State–Response (DSR),
and Driving force–Pressure–State–Impact–Response (DPSIR)). These frameworks have made an important contribution by emphasising
the importance of causality. However, the reliance on simple uni-directional chains is at the same time not very conducive
to a good understanding of the complexity of the processes behind environmental indicators. This limits the usefulness of
these frameworks for environmental (impact) assessments. In this paper we propose an enhanced DPSIR (eDPSIR) framework for
environmental indicators that takes inter-relations of indicators into account by relying on the use of causal networks rather
than causal chains. It will be shown how the concept of causal networks can increase insight into the inter-relation of environmental
issues and associated indicators, can facilitate the identification of key indicators for particular kinds of questions, and
can provide a useful first step to the establishment of dose–response functions. Working with causal networks can contribute
to more appropriate environmental policies and better management decisions. 相似文献
210.
The metabolism of Lindane, gamma-Pentachlorcyclohexene and isomeric Tetrachlorobenzenes in a culture of Mould was investigated in this work. 1,2-, 1,4-Dichlorobenzene, 1,2,3-, 1,2,4-, 1,3,5-Trichlorobenzene, 1,2,3,4-, 1,2,4,5- and/or 1,2,3,5-Tetrachlorobenzene, Pentachlorobenzene, gamma-Pentachlorocyclohexene, Hexachlorobenzene, Tetrachlorocyclohexenol, 2,3,4-, 2,4,6-Trichlorophenol, 2,3,4,5-, 2,3,4,6- and/or 2,3,5,6-Tetrachlorophenol and Pentachlorophenol could be identified as metabolites of Lindane. A degradation scheme is proposed. It includes gamma-Pentachlorocyclohexene, Hexachlorocyclohexene, Pentachlorocyclohexenol, Tetrachlorocyclohexenol and Polychlorophenols as main metabolites. The pathway based on many earlier published experimental results of these and other authors so far as possible.In former papers we have already reported about the known literature concerning the metabolism of Lindane (1 – 4).Comprehensive studies about the metabolism of Lindane in cultures of mould (1, 5, 6), in rats (7 – 9), and in men (2, 3) are to contribute in explaining away any uncertainties about the degradation of Lindane. Many investigations contributed to work out degradation schemes of Lindane (10 – 21). 相似文献