首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   127篇
  免费   0篇
安全科学   12篇
废物处理   3篇
环保管理   36篇
综合类   6篇
基础理论   22篇
污染及防治   37篇
评价与监测   8篇
社会与环境   3篇
  2022年   1篇
  2021年   1篇
  2019年   1篇
  2018年   1篇
  2017年   2篇
  2016年   5篇
  2015年   6篇
  2014年   5篇
  2013年   14篇
  2012年   12篇
  2011年   13篇
  2010年   8篇
  2009年   12篇
  2008年   5篇
  2007年   15篇
  2006年   6篇
  2005年   6篇
  2004年   2篇
  2003年   4篇
  2002年   3篇
  2001年   2篇
  2000年   1篇
  1999年   1篇
  1995年   1篇
排序方式: 共有127条查询结果,搜索用时 156 毫秒
61.
"地方21世纪议程"(LA21)有两个主要目标.①在本研究论文中的一些经验证据的基础上,首要目标是改进民主(环境)决策程序,以便使大多数人能够参与规划和决策,并能够了解这些决策的重大意义.②LA2l程序寻求以既考虑地方的情况又考虑全球情况的方式改善(至少间接地)当地广义的环境状况.本文的第一部分探讨了LA21的概念与方法并阐明对于波罗的海LA2l非常重要的不同的行动领域.此外,研究论文还将描述和展示在一个城市网,即波罗的海城市联盟(uBC)范围内的LA2l形势.包括传递信息、模型及观念的联网是将LA2l理念传播到特别是新近民主化的社会的一个主要手段.最后,本文将对波罗的海边缘的LA2l形势作一全面的评价.  相似文献   
62.
Environmental hazard of heavy metals in soils depends to a large extent on their bioavailability. The approach used in this study enables the determination of bioavailable metals in solid-phase samples. Two recombinant bacterial sensors, one responding specifically to cadmium and the other to lead and cadmium by increase of luminescence (firefly luciferase was used as a reporter) were used to determine the bioavailability of these metals in soil-water suspensions (a contact assay) and respective particle-free extracts. Fifty agricultural soils sampled near zinc and lead smelters in the Northern France containing up to (mg/kg) 20.1 of Cd, 1050 of Pb and 1390 of Zn were analysed. As the soil matrix interferes with the assay, recombinant luminescent control bacteria lacking the metal recognizing protein and corresponding promoter (thus, being not metal-inducible) but otherwise comparable to the sensor bacteria (the same host bacterium and plasmid encoding luciferase) were used in parallel to take into account the possible quenching and/or stimulating effects of the sample on the luminescence of the sensor bacteria. Both, chemical and sensor analysis showed that only microg/l levels of metals were extracted from the soil into the water phase (0.1% of the total Cd, 0.07% of Pb and 0.5% of Zn). However, 115-fold more Cd and 40-fold more Pb proved bioavailable if the sensor bacteria were incubated in soil suspensions (i.e., in the contact assay). The bioavailability of metals in different soils varied (depending probably on soil type) ranging from 0.5% to 56% for cadmium and from 0.2% to 8.6% for lead.  相似文献   
63.
Spray charging of droplets in a wet scrubber   总被引:1,自引:0,他引:1  
The experimental setup was designed to study the effect of natural charging of droplets during spraying (called spray electrification or spray charging) in a wet scrubber. The influence of nozzle material, liquid feed rate, and liquid composition on the specific charge (charge per unit volume of liquid) formed in spraying was measured. It was found that the nozzle material has no measurable effect on this specific charge. Increasing the liquid feed rate increases the specific charge significantly. Increasing solute (NaCl or NaOH) concentration increases the conductivity that decreases the formed specific charge. The same correlation between the specific charge and conductivity was also observed with real scrubbing liquids. It is proposed that the specific charge depends only on the value of liquid conductivity, not on liquid composition. The conductivity of the tested scrubbing liquids was high enough to suppress the formation of a high specific charge during spraying.  相似文献   
64.
In this paper we describe the construction and use of a set of bioluminescent yeast strains for the detection of compounds that can affect androgen or estrogen receptor mediated hormonal signalling. The set includes Saccharomyces cerevisiae strains expressing human androgen receptor (AR), estrogen receptor alpha (ERalpha) or estrogen receptor beta (ERbeta), along with firefly luciferase controlled by a respective hormone responsive promoter. A constitutively luminescent strain was included in the set for determining the cytotoxicity of the sample. Yeast cells were incubated with pure chemicals or complex samples for 2.5 h, after which the signal could be detected from the cell-sample mixture after simply adding the D-luciferin substrate. The assays could be completed in one day and they required no cell lysis or centrifugation steps, which makes them suitable for high-throughput analysis of samples. Due to a short incubation time the assays are directly applicable to different sample matrices, requiring no pretreatment of the samples. The assays were used to assess the hormonal activity in moisturizing lotions as an example of a complex sample matrix known to contain endocrine disrupting chemicals. Six out of eight tested moisturisers showed high estrogenic activity, whereas no androgenic activity was observed in the samples.  相似文献   
65.
In order to be used within Environmental Impact Assessment study, we have developed a three-dimensional particle tracking model for prediction of benthic carbon loading (BCL) caused by fish farms. The model is based on stochastic differential equations for particle transport consistent with the well-known semi-empirical advection/diffusion equation. It requires only easily obtainable input data in the form of measured current record, the source location and a specification of local bathymetry. The model accounts for advection by long-term residual and tidal currents, turbulent diffusion, realistic bathymetry and variations in daily (monthly or yearly) emissions from fish farm.Here, we concentrate on the changes in sedimentation pattern caused by various bathymetric shapes. Examination of idealized cases reveals where and why we can expect the worst impact on benthic communities. For future reference, these results will be included into guidelines for fish farming.  相似文献   
66.
The evolution of ozone (O 3) in the nocturnal and morning-transitional planetary boundary layer (PBL) of the Phoenix valley was measured as a part of the `Phoenix Sunrise Experiment 2001' of the U.S. Department of Energy conducted in June 2001. The goal of the field program was to study the transport, distribution and storage of ozone and its precursors in the urban boundary layer over a diurnal cycle. The ground level O 3 as well as mean meteorological variables and turbulence were measured over the entire period, and vertical profiling (using a tethered balloon) was made during the morning transition period. Approximately half of the observational days showed the usual diurnal cycle of high O 3 during the day and low O 3 at night, with nitrogen oxides (NO x = NO 2 + NO) showing an out of phase relationship with O 3. The rest of the days were signified by an anomalous increase of O 3 in the late evening ( 2200 LST), concomitant with a sudden drop of temperature, an enhancement of wind speed and Reynolds stresses, a positive heat flux and a change of wind direction. NO x measurements indicated the simultaneous arrival of an `aged' air mass, which was corroborated by the wind predictions of a mesoscale numerical model. In all, the results indicate that the recirculation of O 3 rich air masses is responsible for the said high-O 3 events. Such air masses are produced during the transport of O 3 precursors by the upslope flow toward mountainous suburbs during the day, and they return back to the city at night via downslope winds (i.e. mountain breeze). The corresponding flow patterns, and hence the high-O 3 events, are determined by background meteorological conditions. The vertical profiling of O 3 and flow variables during the morning transition points to a myriad of transport, mixing and chemical processes that determine the fate of tropospheric O 3. How well such processes are incorporated and resolved in predictive O 3 models should determine the accuracy of their predictions.  相似文献   
67.
The environmental evaluation of new technology faces many challenges, but at the same time it is an opportunity to take proactive measures to prevent possible negative effects on the environment. Examination of environmental issues using the life cycle approach should form an integrated part of comprehensive technology and product development. The aim of this study was to assess the environmental issues related to a rising technology, printed electronics. Printing is an additive process, having no need for extra material and corrosive chemicals. On the basis of an evaluation made for a prototype product, i.e. a wristband, it was observed that more information on the new materials and further optimization of the process are required before electronics printing can be claimed to be environmentally friendly.  相似文献   
68.
Heat-treated wood is an increasingly popular decoration material. Heat-treatment improves dimensional stability of the wood and also prevents rot fungus growth. Although production of heat-treated wood has been rapidly increasing, there is only little information about the VOC emissions of heat-treated wood and its possible influences on indoor air quality. In the present study, VOC emissions from three untreated (air-dried) and heat-treated wood species were compared during a four weeks test period. It appeared that different wood species had clearly different VOC emission profiles. Heat-treatment was found to decrease VOC emissions significantly and change their composition. Especially, emissions of terpenes decreased from softwood samples and aldehydes from European aspen samples. Emissions of total aldehydes and organic acids were at the same level or slightly higher from heat treated than air-dried softwood samples. In agreement with another recent study, the emissions of furfural were found to increase and those of hexanal to decrease from all the wood species investigated. In contrast to air-dried wood samples, emissions of VOCs were almost in steady state from heat treated wood samples even in the beginning of the test.  相似文献   
69.
The approach to support organizational learning from pro-active monitoring (activities observations) and deficiencies revealed (outcomes observations) in process-safety incident investigations is proposed.The approach builds on five main steps: i.) Implementation of the incident-investigation procedure at the company level, ii.) Monitoring of the preventive safety activities using various tools, iii.) Identification of the safety outcomes including root-cause analysis, iv.) Comparison of activities observations with outcomes observations in order to reveal latent deficiencies as well as to proof relationships, v.) New universal indicator method is proposed to enhance organizational learning from both activities and outcomes observations.The approach is demonstrated on the implementation at the anonymous SME company. This involved carrying out activities observations in terms of the SMS internal audit and the ARAMIS and the violation-motivation safety-culture questionnaire surveys. The outcomes observations consisted of the three incidents investigations using ECFA+, 3CA and MORT methods. The approach and the case study enabled demonstration of the relationships between activities observations (preventive indicators) and outcomes observations (root causes/deficiencies indicators) and vice versa. We state that such a comparison adds to the justification of the preventive safety performance indicators. Finally, in order to ease the organizational learning from both activities and outcomes observations, universal management indicators attributes/categories are suggested to be followed and are briefly explained based on a modified REWI approach.  相似文献   
70.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号