全文获取类型
收费全文 | 333篇 |
免费 | 4篇 |
专业分类
安全科学 | 10篇 |
废物处理 | 11篇 |
环保管理 | 39篇 |
综合类 | 163篇 |
基础理论 | 51篇 |
污染及防治 | 41篇 |
评价与监测 | 13篇 |
社会与环境 | 7篇 |
灾害及防治 | 2篇 |
出版年
2020年 | 4篇 |
2019年 | 5篇 |
2018年 | 4篇 |
2017年 | 7篇 |
2016年 | 8篇 |
2015年 | 7篇 |
2014年 | 9篇 |
2013年 | 11篇 |
2012年 | 6篇 |
2011年 | 11篇 |
2010年 | 8篇 |
2009年 | 9篇 |
2008年 | 8篇 |
2007年 | 7篇 |
2006年 | 7篇 |
2005年 | 5篇 |
2003年 | 6篇 |
2002年 | 7篇 |
1998年 | 5篇 |
1997年 | 6篇 |
1996年 | 5篇 |
1994年 | 11篇 |
1993年 | 9篇 |
1992年 | 4篇 |
1991年 | 6篇 |
1990年 | 8篇 |
1989年 | 6篇 |
1988年 | 3篇 |
1985年 | 5篇 |
1978年 | 5篇 |
1976年 | 5篇 |
1974年 | 4篇 |
1973年 | 4篇 |
1972年 | 5篇 |
1971年 | 3篇 |
1970年 | 7篇 |
1969年 | 3篇 |
1965年 | 4篇 |
1964年 | 5篇 |
1963年 | 3篇 |
1962年 | 4篇 |
1961年 | 4篇 |
1960年 | 5篇 |
1959年 | 5篇 |
1957年 | 7篇 |
1956年 | 4篇 |
1955年 | 9篇 |
1954年 | 4篇 |
1952年 | 3篇 |
1934年 | 4篇 |
排序方式: 共有337条查询结果,搜索用时 390 毫秒
331.
332.
Schneider P Horn K Lauterbach R Hock B 《Environmental pollution (Barking, Essex : 1987)》1990,64(3-4):347-351
The phytohormone GA(3) in needles from 4-year-old Norway spruce trees was analyzed after treatment with ozone and acid mist in environmental chambers under controlled conditions. GA(3) was extracted with methanol from the lyophilized material. Subsequent purification steps included the use of polyvinylpyrollidone (PVP), cartridge reversed-phase purification, ethylacetate extraction and HPLC. The GA(3) was determined in the methylated form by means of a highly specific and sensitive enzyme immunoassay. Higher GA(3) contents were detected in young needles (year 1987) as compared to older ones (year 1986). However, no statistically significant differences were found in the GA(3) levels between the controls and the needles of trees which were treated with increased levels of ozone and acidic mist. 相似文献
333.
334.
Oliver Wings Márton Rabi J?rg W. Schneider Leonie Schwermann Ge Sun Chang-Fu Zhou Walter G. Joyce 《Die Naturwissenschaften》2012,99(11):925-935
A spectacular new terrestrial Konzentratlagerst?tte is introduced from the Turpan Basin of Xinjiang, China that probably belongs to the late Middle Jurassic Qigu Formation. It contains a mass accumulation of “xinjiangchelyid” turtles preliminarily identified as Annemys sp. In the zone with the highest turtle concentration, complete and articulated turtle skeletons are tightly packed at a density of up to 36 turtles per square meter. The fossiliferous layer is thickened here and shows an erosional base. This high concentration zone outcrops approximately 10?m in length and shows no decrease in turtle density after exposing 2?m of the layer into the hillside. Adjacent is a more expansive zone of at least 10?m by 30?m. In this region, the fossiliferous layer is evenly thick, and approximately five, fully disarticulated turtles are present per square meter. A conservatively estimated 1,800 turtles may, therefore, have been deposited at this site. It is likely that these aquatic turtles gathered in a retreating water hole in a riverine environment during a drought, much as some aquatic turtles will do today, but perished when the habitat dried up completely. A following catastrophic rainfall event caused a debris flow, possibly channelized in a dry river bed, which transported complete turtles, disarticulated turtles, and mudstone clasts and deposited them after a short distance. This taphonomic model is consistent with previous environmental reconstructions of the Turpan Basin during the late Middle Jurassic in predicting the episodic breakdown of regional monsoonal circulation resulting in a seasonally dry climate with severe episodic droughts. 相似文献
335.
Kerstin?JantkeEmail author Uwe?A.?Schneider 《Environmental Modeling and Assessment》2011,16(3):227-238
Nature reserves are often designated ad hoc. Despite increasing conservation efforts, loss of biodiversity is still accelerating.
Considering land scarcity and demand for alternative uses, efficiency in conservation strongly correlates with efficiency
in land allocation. Systematic conservation planning can effectively prioritize conservation activities. Previous studies
minimize opportunity costs for given conservation targets. However, these studies assume constant marginal costs of habitat
protection. We extend this cost minimization approach by also considering a dynamic representation of marginal costs. The
more land is allocated to nature reserves, the higher are opportunity costs, i.e., costs of forgone agricultural production.
This increase in costs results from changes in the prices of agricultural commodities. We employ a deterministic, spatially
explicit mathematical optimization model to allocate species habitats by minimizing opportunity costs for setting aside land
for conservation purposes. The model is designed as a mixed integer programming problem and solved with GAMS/CPLEX. Our results
show the need for integrating land market feedbacks into conservation planning. We find that ignoring land rent adjustments
can lead to highly cost-ineffective solutions in reserve selection. 相似文献
336.
Schneider Tobias Musa Bandowe Benjamin A. Bigalke Moritz Mestrot Adrien Hampel Henrietta Mosquera Pablo V. Fränkl Lea Wienhues Giulia Vogel Hendrik Tylmann Wojciech Grosjean Martin 《Environmental science and pollution research international》2021,28(13):16227-16243
Environmental Science and Pollution Research - Historical records of trace elements in lake sediments provide source-to-sink information about potentially toxic pollutants across space and time. We... 相似文献
337.
Temporal evolution of redox processes and free Cd dynamics in a metal-contaminated soil after rewetting 总被引:3,自引:0,他引:3
Soil testing procedures to address metals bioavailability currently use air-dried soil rewetted almost until saturation. Such practices may influence the redox state of soil and the related dynamics of metals. To assess this potential impact, a metal-contaminated soil was air-dried and rewetted to 90% water holding capacity. We monitored over a 21-day incubation period the temporal changes of soil redox potential and solution Cd concentration (either total or free). Other physico-chemical parameters were followed notably pH, ionic strength (I) and the concentrations of NO(3)(-), Mn, Fe and SO(4)(2-) in solution. Soil redox potential showed the progressive establishment of strong reducing conditions in soil, in agreement with the temporal changes of NO(3)(-), Mn, Fe and SO(4)(2-) concentrations. It decreased by 13 pe units over the culture period leading to sulphate-reducing conditions (pe<-3) within only 21days. Solution Cd concentration increased transitorily over the first 100-150h of incubation (2-fold increase) in relation with the parallel increase in the concentration of competing cations for adsorption (Ca, Mg). It steeply decreased over the last 300h of incubation (30-fold decrease) as a result of Cd precipitation as Cd sulphides. This biphasic evolution of Cd dynamics was related to the temporal changes of Cd resupply from the solid phase. Using the technique of DGT we described the kinetics of Cd resupply over time and needed to invoke the existence of two pools of Cd. 相似文献