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131.
以太湖15个入湖河流之一的社渎港为研究对象,利用社渎港流域的水环境质量监测数据、工业企业污染排放调查数据、环境统计数据及社会经济统计数据,对社渎港流域产业结构的合理性进行了诊断,并采用典型相关分析方法探讨了产业结构演变对水环境的影响。结果表明,研究区的工业污染总体上得到了较好控制,其中屺亭街道的工业污染排放最为严重;城乡生活污染和农业面源污染是研究区水环境质量恶化的主要原因,城乡生活污染对COD和氨氮入河量的贡献率较高,分别为46.59%和60.55%,农业面源污染对TN和TP入河量的贡献率突出,分别为64.05%和76.50%;研究区产业结构与钱纳里三次产业结构模式(产业结构合理程度的参照标准)的Hamming贴近度从2001年的0.83下降到2007年的0.77,产业结构不尽合理,且不合理程度逐渐加剧;研究区第一产业对TN和TP入河量的影响最为显著,第三产业对氨氮和COD入河量的影响最为明显;可通过优化产业结构来减轻研究区的水环境污染状况,产业结构调整的主要目标应为降低第二产业产值比例及增加第三产业产值比例。  相似文献   
132.
On the Kola Peninsula, the mining and concentration industry exerts anthropogenic impact on the environment. Tailing dumps cause airborne pollution through dusting, and waterborne pollution due to direct dumping and accidental releases. The objectives were: (1) to analyse multidate satellite imagesfor 1964–1996 to assess the environmental pollution from themining and concentration activity in the Kola in temporal perspective; (2) to evaluate remote sensing methods for integrated environmental impact assessment. The area of mining and industrial sites steadily expands and amounted to 94 km2 in 1996. The polluted water surface amounted to at least 150 km2 through dumping in 1978 and to 106 km2 in1986 due to dusting. Thus, the impact from the mining and concentration activity should be reconsidered as more significant than it was officially anticipated. In the past the main mechanism of pollution wasdirect dumping into the lakes. Currently and in future, airborne pollution after dusting storms will dominate. The effective recultivation of the tailing dumps will be a long-term process. For effective assessment of impacts from the mining and concentration industry, remote sensing methods should be complemented by in-situ measurements, fieldwork, and mathematical modelling.  相似文献   
133.
The growing interest of stakeholders regarding the contribution of organizations to Sustainable Development is influencing organizational behavior and strategic planning. The purpose of the present paper is to analyze the perception of the importance of organizational sustainability dimensions in a relevant economic sector: the metal industry. Survey data was collected from a sample of 211 Portuguese industries, and non-parametric statistical tests were used to validate five research hypotheses regarding the importance of the economic, environmental, social and cultural dimensions of sustainability. The results obtained demonstrate awareness of the sampled industries regarding all sustainability dimensions, recognizing that their importance has been increasing over the years, and prospecting that this importance will continue to increase in the future. The industries in this sample revealed different degrees of perceived importance for the different sustainability dimensions: the highest importance was given to the economic dimension, and culture was considered the least important sustainability dimension. However, the perception of the respondents is that these differences will be less relevant in the future. The results also show that companies with certified management systems reveal a higher perceived importance regarding sustainability dimensions. Also, industries with higher values of annual turnover, number of employees and export sales tend to give higher degrees of importance to sustainability dimensions. Considering the economic, environmental and social impacts of metal industries at an international level, the awareness of this industrial sector regarding the importance of sustainability is a relevant step to the commitment towards Sustainable Development.  相似文献   
134.
Extracellular, oxidative soil enzymes like monophenol oxidases and peroxidases play an important role in transformation of xenobiotics and the formation of organic matter in soil. Additionally, these enzymes may be involved in the formation of non-extractable residues (NERs) of xenobiotics during humification processes. To examine this correlation, the fate of the fungicide 14C metalaxyl in soil samples from Ultuna (Sweden) was studied. Using different soil sterilization techniques, it was possible to differentiate between free, immobilized, and abiotic (“pseudoenzyme”-like) oxidative activities. A correlation between the formation of metalaxyl NER and soil organic matter content, biotic activities, as well as extracellular phenoloxidase and peroxidase activities in the bulk soil and its particle size fractions was determined. Extracellular soil-bound enzymes were involved in NER formation (up to 8% of applied radioactivity after 92 days) of the fungicide independently from the presence of living microbes and different distributions of the NER in the soil humic subfractions.  相似文献   
135.
Abstract

Metabolic fate of two dichloromethyl diaryl phosphonates (32P labelled) in/on rice plants was investigated. The test compounds were found to be less persistent on the surface of rice leaves with half lives 7.4 and 6.7 days respectively. Main degradation product from both the phosphonates were dichloromethyl phosphonic acid with trace of dichloromethyl‐O‐aryl phosphonate as a transitory intermediate product.  相似文献   
136.
资本结构是企业筹资的核心问题之一,上市公司资本结构是否合理直接关系到其企业价值最大化的实现.以纺织行业上市公司公开数据为样本,运用回归分析方法,分析影响我国纺织行业资本结构的因素,认为:资本结构与企业获利能力、资产担保价值正相关,与企业规模负相关,与成长性、实际税率相关不明显.  相似文献   
137.
20世纪80年代以来,再生资源产业被许多国家作为战略性产业而得到迅速发展。近年来,我国再生资源产业发展较快,但与发达国家相比还存在较大差距,总结和借鉴发达国家的经验,并提出推进加快产业发展的对策具有重要的现实意义。  相似文献   
138.
火力发电行业主要气态污染物排放量计算方法研究   总被引:1,自引:0,他引:1  
针对目前我国火力发电行业气态污染物排放量计算方法使用混乱的情况,根据欧盟《空气污染物排放清单指南》和美国《空气污染物排放因子汇编》,介绍了火电行业主要气态污染物排放量的实际测量及理论计算方法。提出我国火电行业应根据实际情况,选择实际测量、排放因子或经验公式等方法计算污染物排放量;使用排放因子方法计算SO2排放量时,应开展S元素转化率的研究;火电厂应增加燃料中N元素的分析,以利于NOx排放量的准确估算。  相似文献   
139.
The fate of 14C-labeled sulfadiazine (14C-SDZ) residues was studied in time-course experiments for 218 days of incubation using two soils (Ap horizon of loamy sand, orthic luvisol; Ap horizon of silt loam, cambisol) amended with fresh and aged (6 months) 14C-manure [40 g kg?1 of soil; 6.36 mg of sulfadiazine (SDZ) equivalents per kg of soil], which was derived from two shoats treated with 14C-SDZ. Mineralization of 14C-SDZ residues was below 2% after 218 days depending little on soil type. Portions of extractable 14C (ethanol-water, 9:1, v/v) decreased with time to 4–13% after 218 days of incubation with fresh and aged 14C-manure and both soils. Non-extractable residues were the main route of the fate of the 14C-SDZ residues (above 90% of total recovered 14C after 218 days). These residues were high immediately after amendment depending on soil type and aging of the 14C-manure, and were stable and not remobilized throughout 218 days of incubation. Bioavailable portions (extraction using CaCl2 solution) also decreased with increasing incubation period (5–7% after 218 days). Due to thin-layer chromatography (TLC), 500 μg of 14C-SDZ per kg soil were found in the ethanol-water extracts immediately after amendment with fresh 14C-manure, and about 50 μg kg?1 after 218 days. Bioavailable 14C-SDZ portions present in the CaCl2 extracts were about 350 μg kg?1 with amendment. Higher concentrations were initially detected with aged 14C-manure (ethanol-water extracts: 1,920 μg kg?1; CaCl2 extracts: 1,020 μg kg?1), probably due to release of 14C-SDZ from bound forms during storage. Consistent results were obtained by extraction of the 14C-manure-soil samples with ethyl acetate; portions of N-acetylated SDZ were additionally determined. All soluble 14C-SDZ residues contained in 14C-manure contributed to the formation of non-extractable residues; a tendency for persistence or accumulation was not observed. SDZ's non-extractable soil residues were associated with the soluble HCl, fulvic acids and humic acids fractions, and the insoluble humin fraction. The majority of the non-extractable residues appeared to be due to stable covalent binding to soil organic matter.  相似文献   
140.
再生资源产业对于破解我国资源环境约束、推动新型城镇化建设和促进产业结构调整具有重要的支撑作用.但是我国再生资源产业处于发展初期,面临管理体系不善、技宋鬟备落后、产业规 缺位和产业政策不清等突出问题.对此,提出六点具体建议,包括:加强立法和产业发展的顶层设计,构建再生资源高效回收体系,推动技术装备升级和推广,完善配套财税政策,强化产业规划统筹和部门政策衔接,加强与新型城镇化建设的融合等.  相似文献   
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