全文获取类型
收费全文 | 180篇 |
免费 | 2篇 |
国内免费 | 2篇 |
专业分类
安全科学 | 11篇 |
废物处理 | 9篇 |
环保管理 | 24篇 |
综合类 | 52篇 |
基础理论 | 42篇 |
污染及防治 | 35篇 |
评价与监测 | 5篇 |
社会与环境 | 6篇 |
出版年
2021年 | 2篇 |
2020年 | 3篇 |
2019年 | 2篇 |
2018年 | 7篇 |
2017年 | 6篇 |
2016年 | 6篇 |
2015年 | 5篇 |
2014年 | 5篇 |
2013年 | 10篇 |
2012年 | 6篇 |
2011年 | 5篇 |
2010年 | 9篇 |
2009年 | 6篇 |
2008年 | 7篇 |
2007年 | 9篇 |
2005年 | 7篇 |
2004年 | 7篇 |
2003年 | 3篇 |
2002年 | 5篇 |
2001年 | 5篇 |
2000年 | 5篇 |
1994年 | 4篇 |
1993年 | 3篇 |
1992年 | 3篇 |
1989年 | 3篇 |
1988年 | 2篇 |
1987年 | 3篇 |
1986年 | 2篇 |
1985年 | 4篇 |
1984年 | 3篇 |
1983年 | 4篇 |
1981年 | 2篇 |
1980年 | 1篇 |
1979年 | 3篇 |
1975年 | 1篇 |
1972年 | 2篇 |
1970年 | 1篇 |
1969年 | 1篇 |
1968年 | 1篇 |
1967年 | 1篇 |
1965年 | 1篇 |
1964年 | 1篇 |
1963年 | 1篇 |
1962年 | 1篇 |
1960年 | 1篇 |
1956年 | 2篇 |
1955年 | 2篇 |
1951年 | 2篇 |
1948年 | 1篇 |
1931年 | 2篇 |
排序方式: 共有184条查询结果,搜索用时 31 毫秒
1.
Yi Shi Akintunde Babatunde Bettina Bockelmann-Evans Qijie Li Liang Zhang 《环境科学学报(英文版)》2020,32(10):151-162
Within the drinking water distribution system (DWDS) using chloramine as disinfectant, nitrification caused by nitrifying bacteria is increasingly becoming a concern as it poses a great challenge for maintaining water quality. To investigate efficient control strategies, operational conditions including hydraulic regimes and disinfectant scenarios were controlled within a flow cell experimental facility. Two test phases were conducted to investigate the effects on the extent of nitrification of three flow rates (Q = 2, 6, and 10 L/min) and four disinfection scenarios (total Cl2=1 mg/L, Cl2/NH3-N=3:1; total Cl2=1 mg/L, Cl2/NH3-N=5:1; total Cl2=5 mg/L, Cl2/NH3-N=3:1; and total Cl2=5 mg/L, Cl2/NH3-N=5:1). Physico-chemical parameters and nitrification indicators were monitored during the tests. The characteristics of biofilm extracellular polymetric substance (EPS) were evaluated after the experiment. The main results from the study indicate that nitrification is affected by hydraulic conditions and the process tends to be severe when the fluid flow transforms from laminar to turbulent (2300<Re<4000). Increasing disinfectant concentration and optimizing Cl2/NH3-N mass ratio were found to inhibit nitrification to some extend when the system was running at turbulent condition (Q = 10 L/min, Re = 5535). EPS extracted from biofilm that was established at the flow rate of 6 L/min had greater carbohydrate/protein ratio. Furthermore, several nitrification indicators were evaluated for their prediction efficiency and the results suggest that the change of nitrite, together with total organic carbon (TOC) and turbidity can indicate nitrification potential efficiently. 相似文献
2.
3.
4.
Franz Huber 《Die Naturwissenschaften》1992,79(9):393-406
Crickets, tettigoniids (bush crickets or long-horned grasshoppers) and acridids (short-horned grasshoppers) are well-suited animals to study acoustically mediated behavior and to search for the underlying sensory, nervous, and effector mechanisms. Several behavioral tactics are described which improve reproductive success, serve to avoid predators such as bats, or have been developed for defence against parasitic insects. Phonotactic orientation of female crickets toward the calling male was chosen, since for this behavior the underlying sensory and nervous mechanisms have been intensively studied. Song recognition was found to be based on one critical parameter of the song, thesyllable period, and the females show abandpass behavior for which a correlate exists inlocal brain neurons. Sound orientation is based on apressure gradient mechanism in each ear, and it needs abinaural intensity comparison within the central nervous system. With intracellular recordings from auditory interneurons during phonotactic orientation and their manipulation, a cellular correlate could be found which obeys the rule “turn to the side most strongly stimulated”. 相似文献
5.
6.
7.
8.
A supportive attitude of residents towards protected areas is crucial for successful implementation and management, particularly in densely populated regions such as Central Europe. While previous studies have revealed that emotional and cultural drivers, as well as information level and group membership, can influence attitudes towards protected areas, the effect of place-attachment dimensions remains unclear. A postal survey among local residents (N = 460) explored factors influencing attitudes towards the Lungau (-Nockberge) Biosphere Reserve in Austria before its official recognition. Results indicated societal support throughout all socio-demographic strata. A logistic regression showed that, besides socio-demographics and information level, place attachment had a significant influence on the acceptance of the biosphere reserve. Supporters and opponents showed both high place identity and dependence, while waverers scored low on these dimensions. Results indicate that place attachment is relevant for the design of participatory processes as well as for developing management policies for biosphere reserves. 相似文献
9.
Ovidiu Badea Andrzej Bytnerowicz Diana Silaghi Stefan Neagu Ion Barbu Carmen Iacoban Corneliu Iacob Gheorghe Guiman Elena Preda Ioan Seceleanu Marian Oneata Ion Dumitru Viorela Huber Horia Iuncu Lucian Dinca Stefan Leca Ioan Taut 《Environmental monitoring and assessment》2012,184(12):7491-7515
Air pollution, bulk precipitation, throughfall, soil condition, foliar nutrients, as well as forest health and growth were studied in 2006–2009 in a long-term ecological research (LTER) network in the Bucegi Mountains, Romania. Ozone (O3) was high indicating a potential for phytotoxicity. Ammonia (NH3) concentrations rose to levels that could contribute to deposition of nutritional nitrogen (N) and could affect biodiversity changes. Higher that 50% contribution of acidic rain (pH?<?5.5) contributed to increased acidity of forest soils. Foliar N concentrations for Norway spruce (Picea abies), Silver fir (Abies alba), Scots pine (Pinus sylvestris), and European beech (Fagus sylvatica) were normal, phosphorus (P) was high, while those of potassium (K), magnesium (Mg), and especially of manganese (Mn) were significantly below the typical European or Carpathian region levels. The observed nutritional imbalance could have negative effects on forest trees. Health of forests was moderately affected, with damaged trees (crown defoliation >25%) higher than 30%. The observed crown damage was accompanied by the annual volume losses for the entire research forest area up to 25.4%. High diversity and evenness specific to the stand type’s structures and local climate conditions were observed within the herbaceous layer, indicating that biodiversity of the vascular plant communities was not compromised. 相似文献
10.
Peter Leinweber Ulrich Bathmann Uwe Buczko Caroline Douhaire Bettina Eichler-Löbermann Emmanuel Frossard Felix Ekardt Helen Jarvie Inga Krämer Christian Kabbe Bernd Lennartz Per-Erik Mellander Günther Nausch Hisao Ohtake Jens Tränckner 《Ambio》2018,47(1):3-19
This special issue of Ambio compiles a series of contributions made at the 8th International Phosphorus Workshop (IPW8), held in September 2016 in Rostock, Germany. The introducing overview article summarizes major published scientific findings in the time period from IPW7 (2015) until recently, including presentations from IPW8. The P issue was subdivided into four themes along the logical sequence of P utilization in production, environmental, and societal systems: (1) Sufficiency and efficiency of P utilization, especially in animal husbandry and crop production; (2) P recycling: technologies and product applications; (3) P fluxes and cycling in the environment; and (4) P governance. The latter two themes had separate sessions for the first time in the International Phosphorus Workshops series; thus, this overview presents a scene-setting rather than an overview of the latest research for these themes. In summary, this paper details new findings in agricultural and environmental P research, which indicate reduced P inputs, improved management options, and provide translations into governance options for a more sustainable P use. 相似文献