Assessing groundwater quality and its sustainability in Joypurhat district of Bangladesh using GIS and multivariate statistical approaches

Sustainable groundwater quality is a key global concern and has become a major issue of disquiets in most parts of the world including Bangladesh. Hence, the assessment of groundwater quality is an important study to ensure its sustainability for various uses. In this study, a combination of multivariate statistics, geographical information system (GIS) and geochemical approaches was employed to evaluate the groundwater quality and its sustainability in Joypurhat district of Bangladesh. The results showed that the groundwater samples are mainly Ca–Mg–HCO₃ type. Principal component analysis (PCA) results revealed that geogenic sources (rock weathering and cation exchange) followed by anthropogenic activities (domestic sewage and agro-chemicals) were the major factors governing the groundwater quality of the study area. Furthermore, the results of PCA are validated using the cluster analysis and correlation matrix analysis. Based on the groundwater quality index (GWQI), it is found that all the groundwater samples belong to excellent to good water quality domains for human consumption, although iron, fluoride and iodide contaminated to the groundwater, which do not pose any significant health hazard according to World Health Organization’s and Bangladesh’s guideline values. The results of irrigation water quality index including sodium adsorption ratio (SAR), permeability index and sodium percentage (Na %) suggested that most of the groundwater samples are good quality water for agricultural uses. The spatial distribution of the measured values of GWQI, SAR, Fe (iron), EC (electrical conductivity) and TH (total hardness) were spatially mapped using the GIS tool in the study area.     

水中总氮测定方法存在问题的研究及改进

碱性过硫酸钾消解紫外分光光度法测定水中总氮采用的消解器皿是玻璃比色管,易造成空白偏高、结果偏低等问题。采用双圆柱状的消解杯对水样进行消解。结果表明,消解杯消解水中总氮,线性相关系数均大于0.999,检出限为0.05 mg/L,相对标准偏差小于5%,相对误差为0.88%~1.00%;改进后的消解器皿具有较好的精密度和准确度,能够更加准确测定水中总氮的含量。     

Characteristic and mechanism of sorption and desorption of benzene on humic acid

Environmental Science and Pollution Research - The sorption/desorption behaviors of benzene, toluene, ethylbenzene, and xylene (BTEX) on soil organic matter (SOM) have a significant influence on...     

Toxic cyanobacteria and microcystin dynamics in a tropical reservoir: assessing the influence of environmental variables

Environmental Science and Pollution Research - Toxic cyanobacterial blooms (TCBs) have become a growing concern worldwide. The present study investigated the dynamic of toxic cyanobacteria and...     

异戊醇低压热解的同步辐射真空紫外光电离质谱研究

作为新兴生物燃料,大分子醇类燃料在低压下的火灾安全基础迫切需要得到深入研究。热解过程作为火灾过程的初始阶段直接控制着火过程,火灾中碳烟颗粒的产生也依赖于热解反应,因此可燃物的低压热解研究在其低压火灾基础研究中具有重要意义。利用同步辐射真空紫外光电离质谱方法研究了异戊醇在0.2atm下的流动反应器热解,探测到了20余种热解产物,包括烯丙基自由基和C_4H_8O、C_5H_8、C_6H_6等同分异构体,并测量了其摩尔分数。基于实验结果,对燃料分解路径和主要产物的生成及消耗路径进行了探讨。与本组之前正戊醇热解实验的对比表明,由于存在支链结构,异戊醇在热解中比正戊醇更容易产生戊烯、丁烯和丙烯,但更少地产生乙烯。此外,异戊醇在热解中能够生成更多的丙炔和丙二烯等环状化合物前驱体,令其苯和1,3-环戊二烯的生成量更高,表明异戊醇比正戊醇更易于生成多环芳烃和碳烟。     

石家庄市春季大气颗粒物的铅污染特征

为了解石家庄市2016年春季大气颗粒物的铅污染特征及来源,利用单颗粒气溶胶质谱仪(SPAMS),分析了大气中含铅颗粒的化学成分。结果表明: 研究期间大气环境中含铅颗粒数浓度共出现11次跳跃式升高,跳跃时间段内石家庄均处于轻度污染过程。从成分分析来看,含铅颗粒分为纯铅颗粒、Pb与K(Pb-K)、OC(Pb-OC)、Cl(Pb-Cl)、混合颗粒等八大类。观测结果表明:Pb-K颗粒最多,占到含铅颗粒的84.4%；其次为纯铅颗粒,占比为13.0%。与石家庄市污染源谱库比对进行来源解析,得到Pb-K颗粒主要来自生活垃圾焚烧源, 纯铅颗粒主要来自工业源。结合石家庄市大气污染源排放清单和后向气流轨迹分析,推测含铅颗粒可能来自市区西南方向某区县的生活垃圾焚烧企业。     

The associations of air pollution exposure during pregnancy with fetal growth and anthropometric measurements at birth: a systematic review and meta-analysis

Environmental Science and Pollution Research - Fetal growth has been demonstrated to be an important predictor of perinatal and postnatal health. Although the effects of maternal exposure to air...     

基于证据法学的环境监测原始记录设计

从证据法学概念的角度浅析了环境监测原始记录的证据范畴,根据其所属范畴的证据要求,归纳了环境监测原始记录的证据要求。结合实例,分析了环境监测原始记录存在的不足,并提出了改进建议。     

气质联用法测固定污染源中三氟甲烷、四氟甲烷、六氟乙烷和六氟化硫

建立了固定污染源排气中三氟甲烷、四氟甲烷、六氟乙烷和六氟化硫的采样和气质联用分析方法,检出限分别为0.06、0.15、0.21、0.71 mg/m3,精密度在3.2%以下,相关系数大于0.999 6,并对浙江省内2家典型企业排放的温室气体进行了监测,实际样品监测结果表明,该方法能够满足废气中4种温室气体的监测要求。     

蒽醌修饰石墨毡电极预处理头孢合成废水

以钛涂钌电极为阳极、自制蒽醌修饰石墨毡电极为阴极,对头孢合成废水(COD=25 000~30 000 mg/L、ρ(NH3-N)=850~1 300 mg/L、色度为2 300~2 680度)进行了电化学氧化预处理,优化了电解条件,并对电化学体系的动力学和稳定性进行了分析。实验结果表明:蒽醌的存在可改善电化学氧化降解效果;在电解时间50 min、电流密度0.14 A/cm2、Na2SO4浓度0.1 mol/L、极板间距2 cm、初始废水p H 7.0的条件下,废水的COD、色度、NH3-N的去除率分别可达45.3%,66.9%,33.6%;BOD5/COD由处理前的0.27增至0.40,可生化性得到改善;COD、色度、NH3-N的电化学氧化降解过程均近似符合一级动力学方程;且该电化学体系的应用稳定性良好。