全文获取类型
收费全文 | 197篇 |
免费 | 1篇 |
专业分类
安全科学 | 4篇 |
废物处理 | 8篇 |
环保管理 | 19篇 |
综合类 | 95篇 |
基础理论 | 19篇 |
污染及防治 | 36篇 |
评价与监测 | 6篇 |
社会与环境 | 10篇 |
灾害及防治 | 1篇 |
出版年
2019年 | 4篇 |
2018年 | 2篇 |
2017年 | 2篇 |
2015年 | 3篇 |
2014年 | 6篇 |
2013年 | 9篇 |
2012年 | 3篇 |
2011年 | 7篇 |
2010年 | 10篇 |
2009年 | 12篇 |
2008年 | 10篇 |
2007年 | 6篇 |
2006年 | 4篇 |
2005年 | 3篇 |
2004年 | 7篇 |
2003年 | 10篇 |
2002年 | 6篇 |
2001年 | 3篇 |
2000年 | 2篇 |
1990年 | 2篇 |
1989年 | 2篇 |
1979年 | 2篇 |
1966年 | 2篇 |
1964年 | 1篇 |
1959年 | 1篇 |
1957年 | 2篇 |
1956年 | 2篇 |
1955年 | 4篇 |
1951年 | 3篇 |
1947年 | 1篇 |
1946年 | 1篇 |
1943年 | 3篇 |
1942年 | 1篇 |
1941年 | 2篇 |
1938年 | 3篇 |
1936年 | 3篇 |
1935年 | 1篇 |
1934年 | 6篇 |
1933年 | 5篇 |
1932年 | 3篇 |
1931年 | 2篇 |
1930年 | 3篇 |
1929年 | 2篇 |
1927年 | 4篇 |
1926年 | 4篇 |
1925年 | 2篇 |
1924年 | 4篇 |
1923年 | 2篇 |
1922年 | 2篇 |
1916年 | 1篇 |
排序方式: 共有198条查询结果,搜索用时 15 毫秒
121.
Reyer Christopher P.O Otto Ilona M. Adams Sophie Albrecht Torsten Baarsch Florent Cartsburg Matti Coumou Dim Eden Alexander Ludi Eva Marcus Rachel Mengel Matthias Mosello Beatrice Robinson Alexander Schleussner Carl-Friedrich Serdeczny Olivia Stagl Judith 《Regional Environmental Change》2017,17(6):1639-1650
Regional Environmental Change - This paper synthesizes what is known about the physical and biophysical impacts of climate change and their consequences for societies and development under... 相似文献
122.
Despite a reasonable scientific interest in sexual selection, the general principles of health signalisation via ornamental
traits remain still unresolved in many aspects. This is also true for the mechanism preserving honesty of carotenoid-based
signals. Although it is widely accepted that this type of ornamentation reflects an allocation trade-off between the physiological
utilisation of carotenoids (mainly in antioxidative processes) and their deposition in ornaments, some recent evidence suggests
more complex interactions. Here, we further develop the models currently proposed to explain the honesty of carotenoid-based
signalisation of heath status by adding the handicap principle concept regulated by testosterone. We propose that under certain
circumstances carotenoids may be dangerous for the organism because they easily transform into toxic cleavage products. When
reserves of other protective antioxidants are insufficient, physiological trade-offs may exist between maintenance of carotenoids
for ornament expression and their removal from the body. Furthermore, we suggest that testosterone which enhances ornamentation
by increasing carotenoid bioavailability may also promote oxidative stress and hence lower antioxidant reserves. The presence
of high levels of carotenoids required for high-quality ornament expression may therefore represent a handicap and only individuals
in prime health could afford to produce elaborate colourful ornaments. Although further testing is needed, this ‘carotenoid
maintenance handicap’ hypothesis may offer a new insight into the physiological aspects of the relationship between carotenoid
function, immunity and ornamentation. 相似文献
123.
124.
125.
Remy Albrecht Claude Périssol Florence Ruaudel Jean Le Petit Gérard Terrom 《Waste management (New York, N.Y.)》2010,30(5):764-770
Microbial communities in sewage sludge and green waste co-composting were investigated using culture-dependent methods and community level physiological profiles (CLPP) with Biolog Microplate. Different microbial groups characterized each stage of composting. Bacterial densities were high from beginning to end of composting, whereas actinomycete densities increased only after bio-oxidation phase i.e. after 40 days. Fungal populations become particularly high during the last stage of decomposition. Cluster analyses of metabolic profiles revealed a similar separation between two groups of composts at 67 days for bacteria and fungi. Principal component analysis (PCA) applied to bacterial and fungal CLPP data showed a chronological distribution of composts with two phases. The first one (before 67 days), where the composts were characterized by the rapid decomposition of non-humic biodegradable organic matter, was significantly correlated to the decrease of C, C/N, organic matter (OM), fulvic acid (FA), respiration, cellulase, protease, phenoloxidase, alkaline and acid phosphatases activities. The second phase corresponding to the formation of polycondensed humic-like substances was significantly correlated to humic acid (HA) content, pH and HA/FA. The influent substrates selected on both factorial maps showed that microbial communities could adapt their metabolic capacities to the particular environment. The first phase seems to be focused on easily degradable substrate utilization whereas the maturation phase appears as multiple metabolisms, which induce the release of metabolites and their polymerization leading to humification processes. 相似文献
126.
Paschke A Vrana B Popp P Schüürmann G 《Environmental pollution (Barking, Essex : 1987)》2006,144(2):414-422
Solid phase microextraction (SPME) fibres coated with Carbowax/divinylbenzene and semi-permeable membrane devices (SPMDs) of standard configuration were used to obtain time-weighted average (TWA) field air concentrations of selected chlorinated semi-volatile compounds on a landfill, where large amounts of lindane by-products were deposited, together with other hazardous chemical residues in the past. Additionally, spot sampling with SPME fibres was performed to identify the emission hotspot and sampling rates were determined/predicted for the substances of interest. Both samplers yield comparable TWA air concentrations of lindane and its isomers and of DDT with its metabolites and gain in certainty about the landfill as remaining source of air pollution with these compounds in the region. Both SPME fibres and SPMDs (respective their modifications) can be recommended as sampling tools in process studies and larger air monitoring programmes. However, further calibration studies and field tests are necessary to obtain reliable sampling rates for a wider range of semi-volatile compounds. 相似文献
127.
128.
In 1978 the US Environmental Protection Agency contracted Mathtech Incorporated to identify the impediments to recycling and evaluate their economic effects. The facilities studied represented a cross-section of recycling technologies, ownership types, geographical locations, and recovered products. It was discovered that none of the facilities was economical in the sense of providing the least-cost mode of disposal for municipal solid waste, and all of them suffered net losses in recent operations. Indications were that financial performance would improve slightly. A major deterrent to economical operations was the availability of lower-cost disposal by landfill. 相似文献
129.
130.
Juliane C. Forti Paula G. Lima Andr R. Reis Felipe A. dos Santos Srgio S. Braga 《环境质量管理》2019,28(3):123-130
Solid waste presents the potential for contamination of the soil when it is improperly managed. One of the great challenges of today's society is to promote the proper disposal of municipal solid waste in order to guarantee the safety of public health and to avoid risks to the environment. In this context, the objective of this study is to analyze the concentration profiles of heavy metals and aromatic hydrocarbons of risk that human health in landfill soil. Such works provides an important tool to evaluate the possible presence of contaminants from inappropriate waste disposal, as well as to assist in the management of waste and to prevent environmental contamination. In order to analyze cadmium (Cd), lead (Pb), nickel (Ni), arsenic (As), and mercury (Hg), which are toxic elements, and aromatic hydrocarbons, including benzene, toluene, ethylbenzene, o‐xylene, m‐xylene, and p‐xylene, soil samples were collected at different sites and depths. Neither Cd nor As was detected in any of the samples that were analyzed. Pb levels ranged from 5.34 milligrams per kilograms (mg/kg) to 7.40 mg/kg, Ni levels ranged from 2.17 mg/kg to 3.00 mg/kg, and Hg levels ranged from 75.4 micrograms per kilograms (μg/kg) to 88.3 μg/kg. The aromatic hydrocarbon compounds of benzene, toluene, ethylbenzene, and o‐xylene were below 5.5 μg/kg, and m‐, p‐xylene was below 11 μg/kg. The analysis of heavy metals and aromatic hydrocarbons present in the landfill soil showed concentrations below the soil quality guideline values of the Brazilian National Environment Council (CONAMA) Resolution 420, which has criteria for the presence of chemical substances in soil for Brazil. Therefore, the low levels of chemicals may be related to the operational time of the landfill or to the population profile of the municipality, which is predominantly composed of persons involved in family‐based agriculture. 相似文献