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11.
某合成洋茉莉醛香料厂的生产废水中含有香料、香料副产品、降解物以及原辅材料,具有CODcr浓度高、水质波动大以及水中污染物成分复杂等特点,属于典型的高浓度难降解有机废水,而该厂现有的废水处理工艺不仅流程长、费用高且出水难以达到GB8978—1996一级排放标准。本文采用活性污泥法及MBR工艺研究了洋茉莉醛香料废水的处理效果及其影响因素,并结合GC—MS对降解产物进行了分析。试验结果表明:采用本文方法对洋茉莉醛香料废水有较好的降解作用,可经较少的步骤处理实现达标排放。  相似文献   
12.
SWOT分析方法在城镇环境规划中的应用   总被引:2,自引:1,他引:1  
可持续发展是当今世界的热点课题,城镇环境规划对于中国的城镇可持续发展和社会主义新农村建设具有重要的意义。然而现有的环境规划分析方法大多是对环境现状的直观描述和简单归纳总结,缺少定量的分析,因此。需要全新的分析方法的引入。本文运用综合评判法、矩阵分析、四半维平面坐标、强度梯度等数学手段,将SWOT分析方法引入环境规划领域,构成了一个适合于环境规划决策过程中应用的系统和定量模型。在此基础上,结合某城镇的环境规划实例,深入探讨了在城镇环境规划中如何引入SWOT分析这一重要方法,并成功得出了该镇环境规划的方向和对策,为其他城镇的可持续发展提供理论支持。  相似文献   
13.
山地区生态环境比较脆弱,在经济社会发展的影响下,山地区的生态承载力呈不断下降的趋势。本文在论述生态承载力内涵和计算方法的基拙上,以2008年《重庆统计年鉴》、2008年《重庆渝北统计年鉴》以及2007年渝北区土地利用现状数据为依据,对重庆市渝北区2007年的生态足迹和生态承载力进行了计算与分析,并进一步分析了山地区土地生态赤字产生的原因,包括人口多,坡地多,土壤和大气污染严重等,提出了控制人口数量和质量、大力发展山地区生态农业、优化能源结构等相应的对策。  相似文献   
14.
结合已开发区域的现状调查,对列表分析法在开发区回顾性环境影响评价中的应用进行了介绍。应用结果表明,列表分析法可充分体现回顾性环境影响评价的内容和特点,精炼报告书的编制,同时能很好地指导开发区进一步的开发建设和优化布局。  相似文献   
15.
根据成都市江安河武侯区段2010年11月-2011年3月的水质监测数据,结合中国地表水环境质量标准(GB3838-2002)和四川省实际确定水体中各污染物因子的本底浓度对该区段污水处理环境效益进行了分析。首先通过污染经济损失模型计算COD、BOD5、NH3-N、TP、SS和硫化物对水经济价值的损失率,然后在讨论COD、NH3-N、TP和硫化物减排情况的基础上计算了各种污染指标减排至达标后所产生的环境经济效益。研究结果表明,江安河武侯区段水体污染的综合污染损失率高达99.99%,如果各种污染物减排达标至IV类标准产生的环境经济效益14 912万元人民币/a,而减排达标至III类标准产生的环境经济效益更是高达15 786万元人民币/a。  相似文献   
16.
The temporal distribution of polycyclic aromatic hydrocarbons (PAHs) was investigated in a sediment core from Lake Erhal in Southwest China using gas-chromatography/mass spectrometry (GC/MS) method.The total organic carbon (TOC) normalized total PAHs concentrations (sum of US Environmental Protection Agency proposed 16 priority PAHs) ranged from 31.9 to 269 μg/g dry weight (dw),and were characterized by a slowly increasing stage in the deeper sediments and a sharp increasing stage in the upper sediments.The PAHs in the sediments were dominated by low molecular weight (LMW) PAHs,suggesting that the primary source of PAHs was low- and moderate temperature combustion processes.However,both the significant increase in high molecular weight (HMW) PAHs in the upper sediments and the vertical profile of diagnostic ratios pointed out a change in the sources of PAHs from low-temperature combustion to high-temperature combustion.The ecotoxicological assessment based on consensus-based sediment quality guidelines implied that potential adverse biological impacts were possible for benzo(ghi)perylenelene and most LMW PAHs.In addition,the total BaP equivalent quotient of seven carcinogenic polycyclic aromatic hydrocarbons (BaA,CHr,BbF,BkF,BaP,DBA and INP) was 106.1 ng/g,according to the toxic equivalency factors.Although there was no great biological impact associated with the HMW PAlls,great attention should be paid to these PAH components based on their rapid increase in the upper sediments.  相似文献   
17.
CALPUFF模型在大气环境容量测算中的应用研究   总被引:4,自引:0,他引:4  
本研究利用CALPUFF空气质量扩散模式模拟了凉山州2007年气象场和s02浓度场,通过现状监测结果与模拟结果的比较评述了模型的适用性;并根据西昌市现状污染源和虚拟污染源情况,通过CALPUFF模拟建立大气污染物传递矩阵,结合线性优化模型测算了西昌市大气环境容量。  相似文献   
18.
石灰石粉制浆系统是石灰石-石膏湿法烟气脱硫工艺中脱硫剂浆液干式制备系统的一个主要部分。针对石灰石粉制浆系统传统设计的不足,提出了石灰石浆液罐与粉仓一体化设计的优化方案,具有节省投资、占地小、设计简单紧凑、系统可靠和寿命长的优点,尤其适合我国老小燃煤机组烟气脱硫改造工程。目前已成功应用于多个烟气脱硫工程。  相似文献   
19.
Chemical and microbial methods are the main remediation technologies for chromium-contaminated soil. These technologies have progressed rapidly in recent years; however, there is still a lack of methods for evaluating the chemical and biological quality of soil after different remediation technologies have been applied. In this paper, microbial remediation with indigenous bacteria and chemical remediation with ferrous sulphate were used for the remediation of soils contaminated with Cr(VI) at two levels (80 and 1,276 mg kg?1) through a column leaching experiment. After microbial remediation with indigenous bacteria, the average concentration of water-soluble Cr(VI) in the soils was reduced to less than 5.0 mg kg?1. Soil quality was evaluated based on 11 soil properties and the fuzzy comprehensive assessment method, including fuzzy mathematics and correlative analysis. The chemical fertility quality index was improved by one grade using microbial remediation with indigenous bacteria, and the biological fertility quality index increased by at least a factor of 6. Chemical remediation with ferrous sulphate, however, resulted in lower levels of available phosphorus, dehydrogenase, catalase and polyphenol oxidase. The result showed that microbial remediation with indigenous bacteria was more effective for remedying Cr(VI)-contaminated soils with high pH value than chemical remediation with ferrous sulphate. In addition, the fuzzy comprehensive evaluation method was proven to be a useful tool for monitoring the quality change in chromium-contaminated soils.  相似文献   
20.
Evidence has shown that polymorphisms of various genes known to be involved in estrogen biosynthesis and function are associated with estrogen-dependent diseases (EDDs). These genes include CYP17A1, estrogen receptor 1 (ESR1), and 2 (ESR2). Phthalates are considered estrogenic endocrine disruptors, and recent research has suggested that they may act as a risk factor for EDDs. However, extremely few studies have assessed the effects of gene–environment interaction on these diseases. We recruited 44 patients with endometriosis or adenomyosis, 36 patients with leiomyoma, and 69 healthy controls from a medical center in Taiwan between 2005 and 2007. Urine samples were collected and analyzed for seven phthalate metabolites using liquid chromatography tandem mass spectrometry. Peripheral lymphocytes were used for DNA extraction to determine the genotype of CYP17A1, ESR1, and ESR2. Compared to controls, patients with leiomyoma had significantly higher levels of total urinary mono-ethylhexyl phthalate (ΣMEHP) (52.1 vs. 29.6 μg/g creatinine, p?=?0.040), mono-n-butyl phthalate (MnBP) (75.4 vs. 51.3 μg/g creatinine, p?=?0.019), and monoethyl phthalate (MEP) (103.7 vs. 59.3 μg/g creatinine, p?=?0.031). In contrast, patients with endometriosis or adenomyosis showed a marginally increased level of urinary MEHP only. Subjects who were homozygous for both the ESR1 C allele (rs2234693) and CYP17A1 C allele (rs743572) showed a significantly increased risk for leiomyoma (OR?=?19.8; 95 % CI, 1.70; 231.5; p?=?0.017) relative to subjects with other genotypes of ESR1 and CYP17A1. These results were obtained after adjusting for age, cigarette smoking, MEHP level, GSTM1 genotype and other covariates. Our results suggested that both CYP17A1 and ESR1 polymorphisms may modulate the effects of phthalate exposure on the development of leiomyoma.  相似文献   
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