全文获取类型
收费全文 | 1896篇 |
免费 | 9篇 |
国内免费 | 2篇 |
专业分类
安全科学 | 35篇 |
废物处理 | 60篇 |
环保管理 | 113篇 |
综合类 | 652篇 |
基础理论 | 328篇 |
环境理论 | 7篇 |
污染及防治 | 547篇 |
评价与监测 | 90篇 |
社会与环境 | 73篇 |
灾害及防治 | 2篇 |
出版年
2021年 | 17篇 |
2020年 | 13篇 |
2019年 | 15篇 |
2018年 | 33篇 |
2017年 | 40篇 |
2016年 | 37篇 |
2015年 | 34篇 |
2014年 | 48篇 |
2013年 | 95篇 |
2012年 | 40篇 |
2011年 | 82篇 |
2010年 | 53篇 |
2009年 | 60篇 |
2008年 | 87篇 |
2007年 | 86篇 |
2006年 | 69篇 |
2005年 | 71篇 |
2004年 | 39篇 |
2003年 | 47篇 |
2002年 | 46篇 |
2001年 | 57篇 |
2000年 | 40篇 |
1999年 | 28篇 |
1998年 | 17篇 |
1997年 | 19篇 |
1996年 | 17篇 |
1995年 | 19篇 |
1994年 | 30篇 |
1993年 | 14篇 |
1991年 | 15篇 |
1989年 | 13篇 |
1985年 | 13篇 |
1984年 | 14篇 |
1981年 | 16篇 |
1974年 | 12篇 |
1969年 | 14篇 |
1968年 | 13篇 |
1967年 | 15篇 |
1966年 | 23篇 |
1965年 | 29篇 |
1964年 | 16篇 |
1963年 | 25篇 |
1962年 | 22篇 |
1961年 | 30篇 |
1960年 | 21篇 |
1959年 | 21篇 |
1958年 | 13篇 |
1957年 | 24篇 |
1956年 | 16篇 |
1955年 | 16篇 |
排序方式: 共有1907条查询结果,搜索用时 46 毫秒
891.
892.
893.
Christian Werner Friedrich Köpp Michael Klier Rainer Haus Wilfried Bautzer Klaus Schäfer 《Environmental Sciences Europe》1996,8(3):143-149
The combination of remote sensing methods like Doppler lidar and FTIR allows remote determination of mass fluxes of gases. Doppler lidar measures the three-dimensional wind vector in the vicinity of diffuse sources, or the velocity of air in a chimney plume if an industrial complex is monitored. FTIR is a multicomponent remote sensing method for gas concentrations. The Fourier transformation of an interferogram of a Michelson interferometer within a FTIR system converts the recorded intensity (function of optical path length) to a spectral signal (function of wavenumber). Both information, velocity and concentration, give the mass fluxes of the tracer (gas). A first test was performed at Munich-Nord power station with FTIR and cw-Doppler lidar. Fluxes of CO2, CO, NO, and HCl were determined. The results are in good agreement with the fluxes measured byin situ instruments of the power station. The method can be used to control industrial complexes from an outside observation site. 相似文献
894.
Jens Newig Nicolas W. Jager Elisa Kochskämper Edward Challies 《Journal of Environmental Policy & Planning》2019,21(3):213-227
ABSTRACTTheory on participatory and collaborative governance maintains that learning is essential to achieve good environmental outcomes. Empirical research has mostly produced individual case studies, and reliable evidence on both antecedents and environmental outcomes of learning remains sparse. Given conceptual ambiguities in the literature, we define governance-related learning in a threefold way: learning as deliberation; as knowledge- and capacity-building; and as informing environmental outputs. We develop nine propositions that explain learning through factors characterizing governance process and context, and three propositions explaining environmental outcomes of learning. We test these propositions drawing on the ‘SCAPE’ database of 307 published case studies of environmental decision-making, using multiple regression models. Results show that learning in all three modes is explained to some extent by a combination of process- and context-related factors. Most factors matter for learning, but with stark differences across the three modes of learning, thus demonstrating the relevance of this differentiated approach. Learning modes build on one another: Deliberation is seen to explain both capacity building and informed outputs, while informed outputs are also explained by capacity building. Contrary to our expectations, none of the learning variables was found to significantly affect environmental outcomes when considered alongside the process- and context-related variables. 相似文献
895.
Data from three years of operation of a low-level aerosol sampler and analyzer (RASA) at Schauinsland monitoring station are reported. The system is part of the International Monitoring System (IMS) for verification of the Comprehensive Nuclear-Test-Ban Treaty (CTBT). The fully automatic system is capable to measure aerosol borne gamma emitters with high sensitivity and routinely quantifies 7Be and 212Pb. The system had a high level of data availability of 90% within the reporting period. A daily screening process rendered 66 tentative identifications of verification relevant radionuclides since the system entered IMS operation in February 2004. Two of these were real events and associated to a plausible source. The remaining 64 cases can consistently be explained by detector background and statistical phenomena. Inter-comparison with data from a weekly sampler operated at the same station shows instabilities of the calibration during the test phase and a good agreement since certification of the system. 相似文献
896.
Joseph Alcamo Lilibeth Acosta-Michlik Alexander Carius Frank Eierdanz Richard Klein Dörthe Krömker Dennis Tänzler 《Regional Environmental Change》2008,8(4):137-149
In this study we develop an “inference modeling” approach to compare and analyze how different disciplines (economics, political
science, and behavioral science/environmental psychology) estimate vulnerability to drought. It is thought that a better understanding
of these differences can lead to a synthesis of insights from the different disciplines and eventually to more comprehensive
assessments of vulnerability. The new methodology consists of (1) developing inference models whose variables and assertions
incorporate qualitative knowledge about vulnerability, (2) converting qualitative model variables into quantitative indicators
by using fuzzy set theory, (3) collecting data on the values of the indicators from case study regions, (4) inputting the
regional data to the models and computing quantitative values for susceptibility. The methodology was applied to three case
study regions (in India, Portugal and Russia) having a range of socio-economic and water stress conditions. In some cases
the estimates of susceptibility were surprisingly similar, in others not, depending on the factors included in the disciplinary
models and their relative weights. A new approach was also taken to testing vulnerability parameters by comparing estimated
water stress against a data set of drought occurrences based on media analysis. The new methodologies developed in this paper
provide a consistent basis for comparing differences between disciplinary perspectives, and for identifying the importance
of the differences.
相似文献
Joseph AlcamoEmail: |
897.
Elke?MaierEmail author Ralph?Tollrian Baruch?Rinkevich Beate?Nürnberger 《Marine Biology》2005,147(5):1109-1120
Pelagic dispersal of larvae in sessile marine invertebrates could in principle lead to a homogeneous gene pool over vast distances,
yet there is increasing evidence of surprisingly high levels of genetic differentiation on small spatial scale. To evaluate
whether larval dispersal is spatially limited and correlated with distance, we conducted a study on the widely distributed,
viviparous reef coral Seriatopora hystrix from the Red Sea where we investigated ten populations separated between ~0.150 km and ~610 km. We addressed these questions
with newly developed, highly variable microsatellite markers. We detected moderate genetic differentiation among populations
based on both F
ST and R
ST (0.089 vs. 0.136, respectively) as well as considerable heterozygote deficits. Mantel tests revealed isolation by distance
effects on a small geographic scale (≤20 km), indicating limited dispersal of larvae. Our data did not reveal any evidence
against strictly sexual reproduction among the studied populations. 相似文献
898.
Ecological Sanitation--a way to solve global sanitation problems? 总被引:10,自引:0,他引:10
Today about 2.4 billion people in rural and urban areas do not have access to adequate sanitation services. Within 20 years, it is expected that an additional 2 billion will live in towns and cities, mainly in developing countries, demanding sanitation. Still over 90% of sewage in developing countries is discharged untreated, polluting rivers, lakes and coastal areas. Conventional sanitation concepts, based on flush toilets, a water wasting technology, are neither an ecological nor economical solution in both industrialized and developing countries. The water-based sewage systems were designed and built on the premises that human excreta are a waste; suitable only for disposal and that the environment is capable of assimilating this waste. A sanitation system that provides Ecological Sanitation (EcoSan) is a cycle--a sustainable, closed-loop system, which closes the gap between sanitation and agriculture. The EcoSan approach is resource minded and represents a holistic concept towards ecologically and economically sound sanitation. The underlying aim is to close (local) nutrient and water cycles with as less expenditure on material and energy as possible to contribute to a sustainable development. Human excreta are treated as a resource and are usually processed on-site and then treated off-site. The nutrients contained in excreta are then recycled by using them, e.g., in agriculture. EcoSan is a systemic approach and an attitude; single technologies are only means to an end and may range from near-natural wastewater treatment techniques to compost toilets, simple household installations to complex, mainly decentralised systems. These technologies are not ecological per se but only in relation to the observed environment. They are picked from the whole range of available conventional, modern and traditional technical options, combining them to EcoSan systems. The paper presents an introduction to EcoSan principles and concepts including re-use aspects (available nutrients and occurring risks), and case studies of EcoSan concepts in both industrialized and developing countries. 相似文献
899.
Determination of sorption coefficients of pharmaceutically active substances carbamazepine, diclofenac, and ibuprofen, in sandy sediments 总被引:1,自引:0,他引:1
Laboratory batch studies were conducted to characterize the sorption behavior of three pharmaceutically active substances (carbamazepine, diclofenac, and ibuprofen) in different sediment types. The sediments were natural sandy sediments from the water saturated zone and the unsaturated zone in the Berlin (Germany) area. They are characterized as medium and fine-grained sands, both with low organic carbon content. The results of the experiments show that sorption coefficients were generally quite low. Distribution coefficients (K(d) values) determined by the batch experiments varied from 0.21 to 5.32 for carbamazepine, 0.55 to 4.66 for diclofenac, and 0.18 to 1.69 for ibuprofen. Comparison of the organic carbon normalized sorption coefficient K(OC) values based on correlation equations with actual experimental data revealed that the calculated data for carbamazepine is of the same order as the experimental data. For diclofenac and ibuprofen the calculated values are much higher than the experimental data, showing a much higher mobility of diclofenac and ibuprofen in natural aquifer sediments than indicated by correlation equations based on octanol water distribution coefficients. 相似文献
900.