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1.
环保科技投入与环保产业发展的区域差异研究   总被引:1,自引:0,他引:1  
采用多维区域差异指数衡量了1994—2000年间环保科技投入的地区差异和1996—2000年间环保产业年产值的地区间差异,得到了两者的年度变化趋势,并分析了近年来环保科技投入地区差异扩大的原因。  相似文献   

2.
王兆龙  单伟 《污染防治技术》2009,22(6):39-40,56
阐述了循环经济的内涵、特点,分析了循环经济理念导人环境影响评价中应注意的几个环节,探讨了区域生态产业链、物质流分析法、循环经济指标等在区域规划环境影响评价中的应用,并提出了相关的建议及措施。  相似文献   

3.
本文根据太湖流域的环境特征,探讨性地提出了太湖水域环境保护功能区的划分,其目的是为了管理好太湖、利用好太湖。  相似文献   

4.
本文对区域总量控制管理中利用市场机制的经济规律、政策意义和可行性给予分析,有控制地利用市场机制进行排污量转让,有益于水质管理工作。  相似文献   

5.
对山一村 1 0年来的发展过程作了比较评述 ,并对生态村如何在市场经济条件下发挥自身优势 ,走经济与环境保护协调发展之路提出了一些探索意见。  相似文献   

6.
一、引言区域环境噪声的预测是一个引人注目的课题。但在通常情况下,由于区域内噪声源分布及声波传播途径的声学性质缺乏规律性,使这一课题的研究颇为困难,只对一些声源分布较为简单的情况取得一定成果。我们认为,对一般区域,尽管声波的传播与衰减确实符合物理规律,但由于声源分布的无规性(包括运动着的声源其坐标的不确定性以及间歇出现的声源其出现时间的不确定性),以及传播途径上声学性质的无规性(例  相似文献   

7.
香港区域发展的策略性环境影响评价(简称环评)从20世纪80年代起步,已形成包括行政规定和法例规定的制度框架,其策略性环评的实践范围也逐步从规划、计划向政策、策略扩展.从评价过程、评价方法、公众参与时段安排、决策出发点等方面分析了2个香港区域发展的策略性环评案例.结果表明,为使策略性环评取得预想的成果并有助于可持续发展,...  相似文献   

8.
根据金坛市城乡分散供水的现状,指出了存在的问题,分析了各水源地的水质、水量以及综合工程投资、施工难度、供水成本、供水安全等因数,并提出了近期和远期实施区域供水的方案,将对发展和完善区域供水的规划与实施具有借鉴作用。  相似文献   

9.
土壤中有机污染物运移模型的对比分析   总被引:2,自引:0,他引:2  
分别建立了考虑非平衡吸附和生物降解的单区域溶质运移动力学模型(简称单区域模型)和两区域溶质运移动力学模型(简称两区域模型),基于数值模拟方法,对两种模型进行了定量的对比分析.分析结果表明,参与流动的水分的含量、不可动水区的持留释放能力是影响污染物在土壤-水环境中分配规律以及两种模型模拟结果之间差异的重要因素;较大的可动水区和不可动水区之间的质量转移系数,可以通过增加持留释放能力而增强不可动水区对溶质运移的影响能力,因此在模拟过程中不应单纯依据不可动水的含量大小来确定采用何种模型进行模拟,而应同时考虑可动水区和不可动水区之间的质量转移系数对模拟效果的影响.  相似文献   

10.
区域环境风险评价方法初探   总被引:1,自引:0,他引:1  
与单个建设项目的环境风险相比,区域环境风险具有多源、多途径和多敏感目标的特点,在未来几十年内,区域环境风险将是环境风险评价的重点研究领域之一,但是由于没有相应的技术导则、规范来指导该章节的编制,《建设项目环境风险评价技术导则》中的评价办法也并不完全适用于区域层面,因此开发区环境风险评价的开展效果并不理想。在分析开发区环境风险评价工作现状及存在问题的基础上,提出了适用于开发区区域环境风险评价的程序及方法。  相似文献   

11.
The sorption and desorption of Cu and Cd by two species of brown macroalgae and five species of microalgae were studied. The two brown macroalgae, Laminaria japonica and Sargassum kjellmanianum, were found to have high capacities at pHs between 4.0 and 5.0 while for microalgae, optimum pH lay at 6.7. The presence of other cations in solution was found to reduce the sorption of the target cation, suggesting a competition for sorption sites on organisms. Sorption isotherms obeyed the Freundlich equation, suggesting involvement of a multiplicity of mechanisms and sorption sites. For the microalgae tested, Spirulina platensis had the highest capacity for Cd, followed by Nannochloropsis oculata, Phaeodactylum tricornutum, Platymonas cordifolia and Chaetoceros minutissimus. The reversibility of metal sorption by macroalgae was examined and the results show that both HCl and EDTA solutions were very effective in desorbing sorbed metal ions from macroalgae, with up to 99.5% of metals being recovered. The regenerated biomass showed undiminished sorption performance for the two metals studied, suggesting the potential of such material for use in water and wastewater treatment.  相似文献   

12.
The kinetic and structural relationships of eight electrophoretically pure mammalian serum and liver serine carboxylesterases (CE) and cholinesterases (ChE) have been studied. Eight CE's and ChE's, which were fully resolved but only partially purified, provided additional information. Five of the electrophoretically pure esterases were monomeric, and of these, four belonged to a new and widely distributed class. These four monomeric esterases hydrolyzed choline esters, but at widely differing rates. Thus two were termed monomeric butyrylcholinesterases, mBuChE I and II, and two were monomeric CE's (mCE). The rabbit liver mCE was not a subunit of the oligomeric CE (oCE), although the oCE also hydrolyzed choline esters at a very low rate. The complex kinetics of the mCE's, mBuChE's, oCE's, and of the oligomeric BuChE's of horse and human serum could be interpreted according to a single reaction scheme involving an allosteric site and the equation derived from it. Thus activation and inhibition at high substrate concentrations, together with sigmoidal activity versus substrate concentration plots, all of which characterize the reactions of these esterases, could be interpreted by a single scheme and equation. Structural and kinetic comparisons showed a progressive transition of properties from the oCE's through the mCE's to the oBuChE's. One of the purified mCE's was from horse serum, and it exhibited physical and kinetic properties unlike those of the liver mCE's or oCE's.  相似文献   

13.
The persistence and dissipation kinetics of trifloxystrobin and tebuconazole on onion were studied after application of their combination formulation at a standard and double dose of 75 + 150 and 150 + 300 g a.i. ha?1. The fungicides were extracted with acetone, cleaned-up using activated charcoal (trifloxystrobin) and neutral alumina (tebuconazole). Analysis was carried out by gas chromatograph (GC) and confirmed by gas chromatograph mass spectrometry (GC-MS). The recovery was above 80% and limit of quantification (LOQ) 0.05 mg kg?1 for both fungicides. Initial residue deposits of trifloxystrobin were 0.68 and 1.01 mg kg?1 and tebuconazole 0.673 and 1.95 mg kg?1 from standard and double dose treatments, respectively. Dissipation of the fungicides followed first-order kinetics and the half life of degradation was 6–6.6 days. Matured onion bulb (and field soil) harvested after 30 days was free from fungicide residues. These findings suggest recommended safe pre-harvest interval (PHI) of 14 and 25 days for spring onion consumption after treatment of Nativo 75 WG at the standard and double doses, respectively. Matured onion bulbs at harvest were free from fungicide residues.  相似文献   

14.

The bioavailability of pollutants, pesticides and/or their degradation products in soil depends on the strength of their sorption by the different soil components, particularly by the clay minerals. This study reports the sorption-desorption behavior of the environmentally hazardous industrial pollutants and certain pesticides degradation products, 3-chloroaniline, 3,4-dichloroaniline, 2,4,6-trichloroaniline, 4-chlorophenol, 2,4-dichlorophenol and 2,4,6-trichlorophenol on the reference clays kaolinite KGa-1 and Na-montmorillonite SWy-l. In batch studies, 2.0 g of clay were equilibrated with 100.0 mL solutions of each chemical at concentrations ranging from 10.0 to 200.0 mg/L. The uptake of the compounds was deduced from the results of HPLC-UV-Vis analysis. The lipophilic species were best retained by both clay materials. The most lipophilic chemical used in the study, 2,4,6-trichloroaniline, was also the most strongly retained, with sorption of up to 8 mg/g. In desorption experiments, which also relied on HPLC-UV-Vis technique, 2,4,6-trichloroaniline was the least desorbed from montmorillonite. However, on kaolinite all of the compounds under study were irreversibly retained. The experimental data have been modelled according to the Langmuir and Freundlich isotherms. A hypothesis is proposed concerning the sorption mechanism and potential applications of the findings in remediation strategies have been suggested.  相似文献   

15.
The bioavailability of pollutants, pesticides and/or their degradation products in soil depends on the strength of their sorption by the different soil components, particularly by the clay minerals. This study reports the sorption-desorption behavior of the environmentally hazardous industrial pollutants and certain pesticides degradation products, 3-chloroaniline, 3,4-dichloroaniline, 2,4,6-trichloroaniline, 4-chlorophenol, 2,4-dichlorophenol and 2,4,6-trichlorophenol on the reference clays kaolinite KGa-1 and Na-montmorillonite SWy-l. In batch studies, 2.0 g of clay were equilibrated with 100.0 mL solutions of each chemical at concentrations ranging from 10.0 to 200.0 mg/L. The uptake of the compounds was deduced from the results of HPLC-UV-Vis analysis. The lipophilic species were best retained by both clay materials. The most lipophilic chemical used in the study, 2,4,6-trichloroaniline, was also the most strongly retained, with sorption of up to 8 mg/g. In desorption experiments, which also relied on HPLC-UV-Vis technique, 2,4,6-trichloroaniline was the least desorbed from montmorillonite. However, on kaolinite all of the compounds under study were irreversibly retained. The experimental data have been modelled according to the Langmuir and Freundlich isotherms. A hypothesis is proposed concerning the sorption mechanism and potential applications of the findings in remediation strategies have been suggested.  相似文献   

16.
Environmental Science and Pollution Research - Hydrocarbon is a primary source of energy in the current urbanized society. Considering the increasing demand, worldwide oil productions are declining...  相似文献   

17.
18.
畜禽养殖业污染与循环经济   总被引:16,自引:0,他引:16  
解决畜禽养殖业的污染问题要以充分利用资源为根本出发点,通过对污染全过程控制及废物综合利用,达到畜禽粪便的减量化、无害化、资源化,走循环经济的发展道路。  相似文献   

19.
The degradation and ecotoxicity of sulfonylurea herbicide rimsulfuron and its major metabolites were examined in batch samples of an alluvial sandy loam and in freshwater. An HPLC-DAD method was adapted to simultaneously identify and quantify rimsulfuron and its metabolites, which was successfully validated by GC-MS analysis. In aqueous solutions, pure rimsulfuron was rapidly hydrolyzed into metabolite 1 (N-(4,6-dimethoxypyrimidin-2-yl)-N-(3-(ethylsulfonyl)-2-pyridinylurea)), which itself was transformed into the more stable metabolite 2 (N-((3-(ethylsulfonyl)-2-pyridinyl)-4,6-dimethoxy-2-pyrimidineamine)), with half-life (t(1/2)) values of 2 and 2.5 days, respectively. Hydrolysis was instantaneous under alkaline conditions (pH = 10). In aqueous suspensions of the alluvial soil (pH = 8), formulated rimsulfuron had a half-life of 7 days, whereas that of metabolite 1 was similar to that in water (about 3.5 days). The degradation of the two major metabolites was also studied in soil suspensions with the pure compounds at concentrations ranging from 1 to 10 mg l(-1). The half-life of metabolite 1 ranged from 3.9 to 5 days, close to the previous values. Metabolite 2 was more persistent and its degradation is strongly dependent on the initial concentration (C0): half-life values ranged from 8.1 to 55 days at 2-10 mg l(-1), respectively. These values are higher than those determined from the kinetics of metabolite 1 transformation into metabolite 2 (t(1/2) = 8-19 days). The ecotoxicity of the three chemicals was evaluated through their effect on Daphnia magna and Vibrio fischeri (Microtox bioassay). No effect was observed on D. magna with 24 and 48 h acute toxicity tests. Similarly, no toxic effect was observed with the Microtox test for the three chemicals in the range of concentrations tested that included the field application dose. Thus, being of low persistence and lacking acute toxicity, these chemicals present a low environmental risk. However, chronic effects should be studied in order to confirm the safety of rimsulfuron and its major metabolites.  相似文献   

20.
Isocyanatocyclohexane and isothiocyanatocyclohexane are becoming relevant compounds in urban and industrial air, as they are used in important amounts in automobile industry and building insulation, as well as in the manufacture of foams, rubber, paints and varnishes. Glass multi-sorbent tubes (Carbotrap, Carbopack, Carboxen) were connected to LCMA-UPC pump samplers for the retention of iso- and isothiocyanatocyclohexanes. The analysis was performed by automatic thermal desorption (ATD) coupled with capillary gas chromatography (GC)/mass spectrometry detector (MSD). TD-GC/MS was chosen as analytical method due to its versatility and the possibility of analysis of a wide range of volatility and polarity VOC in air samples. The method was satisfactory sensitive, selective and reproducible for the studied compounds. The concentrations of iso- and isothioisocyanatocyclohexanes were evaluated in different urban, residential and industrial locations from extensive VOC air quality and odour episode studies in several cities in the Northeastern edge of Spain. Around 200–300 VOC were determined qualitatively in each sample. Higher values of iso- and isothiocyanatocyclohexane were found in industrial areas than in urban or residential locations. The concentrations ranged between n.d.−246 and n.d.−29 μg m−3 for isocyanatocyclohexane and isothiocyanatocyclohexane, respectively, for industrial areas. On the other hand, urban and residential locations showed concentrations ranging between n.d.−164 and n.d.−29 μg m−3 for isocyanatocyclohexane and isothiocyanatocyclohexane, respectively. The site location (urban or industrial), the kind and nearness of possible iso- and isothiocyanatocyclohexane emission activities (industrial or building construction) and the changes of wind regimes throughout the year have been found the most important factors influencing the concentrations of these compounds in the different places.  相似文献   

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