海南省大气环境质量容量和总量分析

大气环境容量,是指在一个特定区域内、一定的气象条件、一定的自然边界条件及一定的排放源结构条件下,在满足该区域大气环境质量目标前提下,所允许的区域大气污染物的最大排放量。本文利用A值法,根据海南省大气环境功能区划及功能区环境质量目标,各工业区面积,大气污染物排放背景值等计算参数,通过对大气环境质量、环境容量及排污总量相关性分析,得出海南省的剩余环境容量,说明海南省在满足总量控制的基础上,还有相当大的发展空间,为经济社会发展和总量控制提供依据。     

乌昌地区大气污染成因分析及应对措施研究

通过介绍乌昌地区概况,结合地区大气污染环境质量现状,从多角度对地区大气污染成因进行分析,结果表明乌昌地区大气污染主要受地形地貌、气象条件、产业结构及能源利用方式不合理、城市规划及基础设施建设落后、行政管理职权划分不明确等因素影响。在此基础上提出针对产业结构、能源结构、采暖模式、城市道路规划、重点企业综合治理、生态建设及环境管理体系等多方面应对措施,以期形成以政府为主导,企业为主体,全社会共同参与的环境保护体系,为政府部门环境保护工作提供参考建议。     

Enhanced debromination of 4-bromophenol by the UV/sulfite process: Efficiency and mechanism

Halogenated aromatic compounds have attracted increasing concerns due to their toxicity and persistency in the environment, and dehalogenation is one of the promising treatment and detoxification methods. Herein, we systematically studied the debromination efficiency and mechanism of para-bromophenol(4-BP) by a recently developed UV/sulfite process. 4-BP underwent rapid degradation with the kinetics accelerated with the increasing sulfite concentration, pH(6.1–10) and temperature, whereas inhibited by dissolved oxygen and organic solvents. The apparent activation energy was estimated to be 27.8 kJ/mol. The degradation mechanism and pathways of 4-BP were explored by employing N_2O and nitrate as the electron scavengers and liquid chromatography/mass spectrometry to identify the intermediates. 4-BP degradation proceeded via at least two pathways including direct photolysis and hydrated electron-induced debromination. The contributions of both pathways were distinguished by quantifying the quantum yields of 4-BP via direct photolysis and hydrated electron production in the system. 4-BP could be readily completely debrominated with all the substituted Br released as Br-, and the degradation pathways were also proposed. This study would shed new light on the efficient dehalogenation of brominated aromatics by using the UV/sulfite process.     

La/Ce-codoped Bi2O3 composite photocatalysts with high photocatalytic performance in removal of high concentration dye

A series of La/Ce-codoped Bi_2O_3 composite photocatalysts were fabricated via hydrothermal–calcination process. The as-prepared products were intensively characterized by some physicochemical characterizations like N_2 physical adsorption, X-ray powder diffraction(XRD), scanning electron microscope(SEM), transmission electron microscope(TEM), UV–Vis diffuse reflectance(UV–Vis DRS), Fourier transform infrared spectroscopy(FT-IR),photoelectrochemical measurements, and photoluminescence(PL) spectroscopy. The characterization results indicated that La and Ce doping induced obvious crystal phase transformation in Bi_2O_3, from monoclinic to tetragonal phase. La and Ce codoping also gave rise to the obvious synergetic effects, e.g., the lattice contraction of Bi_2O_3, the decrease of crystal size and the increase of surface area. The photocatalytic performance of the prepared catalysts was evaluated by removal of dye acid orange II with high concentration under visible light irradiation. Results showed that La/Ce-codoped Bi_2O_3 displayed much higher photocatalytic performance than that of bare Bi_2O_3, single La or Ce doped Bi_2O_3 samples. The superior photocatalytic activity was mainly attributed to the improved texture and surface properties and the synergistic effects of La and Ce codoping on suppressing the recombination of photo-generated electrons(e~-) and holes(h~+).     

考洲洋水环境质量现状及受潮汐影响变化分析

文章应用单因子标准指数法、算术均值多因子指数法和营养状态指数法相结合的方法对当前考洲洋海域海水质量状况进行了评价,并依据考洲洋在潮汐涨、落情况下海水质量的变化,定量分析了考洲洋潮汐对其海水水质的影响。结果表明:磷酸盐、无机氮、石油类是影响考洲洋海域环境质量的主要因子,考洲洋内部海域均处于富营养化状态,总体水质状况为良好以下,潮水的涌入能改善考洲洋的水质状况,涨潮时期各航次的算术均值多因子指数之和比退潮时期平均降低了13.92%。且潮汐的变化对主要污染因子的影响顺序为:无机氮>磷酸盐>石油类,最后提出了考洲洋污染防治的对策和建议。     

高效液相色谱法测定水中两种邻苯二甲酸酯的不确定度研究

对高效液相色谱法测定水中两种邻苯二甲酸酯类化合物过程的不确定度及来源进行了分析和评定.通过数学模型计算分析过程中的各不确定度的分量,最后计算出相对合成不确定度和相对扩展不确定度.其中,邻苯二甲酸二丁酯和甲醇中邻苯二甲酸二(2-乙基己基)酯的相对合成不确定度分别为5.18%和3.93%.根据分析结果,在引起不确定度的因素中,由曲线拟合导致的不确定度分量最大,而样品前处理和方法回收率对不确定度的引入也有较大的影响.     

中国地表水重金属污染的进展研究

为了解中国地表水重金属污染现状,并为水体重金属的治理提供一定依据,通过对地表水体重金属来源、中国各地区地表水重金属污染状况、水体重金属污染防治现状、风险及趋势分析和防治对策这五个方面进行综述.道路雨水径流的无处理排放易造成地表水体重金属的污染;中国许多地区的河流、湖泊等水体都存在重金属污染现象,不同地区污染来源不同,外源污染物输入是重要因素;致癌物镉、铬和砷对人体的健康风险要远远大于非致癌物.     

地表参数设置对高架点源大气污染物扩散预测的影响研究

以某火电厂高架点源为例,运用AERMOD进行预测,对扇区进行粗划分和细划分,设置两组地表参数,分析SO2、NO2、PM10在敏感点的小时浓度、日均浓度和期间平均浓度最大值的差异.变化幅度分析方法表明,PM10的小时浓度、日均浓度、期间平均浓度最大值的变化幅度最大,NO2次之,SO2最小.高端值比较法分析表明,NO2小时浓度最大值的差异最大,SO2次之,PM10最小;NO2日均浓度最大值的差异最大,PM10次之,SO2最小;NO2期间平均浓度最大值的差异最大,SO2次之,PM10最小.     

基于二维水动力水质模拟下水环境容量的求解研究

由于受到适用条件有限、计算烦琐等方面的限制,目前许多水环境容量计算方法难以得到广泛应用,采用了影响系数法,在二维水动力水质模拟的基础上,以下边界上最大浓度点为控制点,计算区域的水环境容量,并对长江仪征工业用水区的水环境容量进行了计算,得出该河段环境容量为17 969.2t/a.该方法计算简单,且综合考虑了控制点的浓度,污染源位置,河流水文,水力学特性等多种因素,是一种非常有效且值得推广的计算方法,可为该区域水资源保护规划提供依据.     

农村水污染防治源头控制政策与技术研究

从源头控制农业污染源进入水体,是实现水质提升的重要途径.目前中国农村污水防治政策制度进入强化和完善阶段,但在某些细化领域还存在空白.农村生活污水和畜禽养殖污水的治理技术比较成熟,而农业种植径流、水产养殖污水、坑塘污水等农村污染源,还未有相关的治理技术指南发布.建议从完善政策法规、强化执法和激励,做好农村发展规划,合理安排种植业、养殖业布局,以及加强资金投入与环境监管等方面加强农村水污染防治工作.