滇池水葫芦规模化控养生态环境效应分析

水葫芦规模化控养是"十二五"期间滇池治理的重要措施之一。首先介绍了滇池水葫芦规模化控养现状,比较了滇池草海和外海在水葫芦控养前后水质的变化情况,指出滇池水葫芦规模化控养对草海水体生态恢复效果显著,可以在滇池选择适宜水葫芦生长的水域继续扩大水葫芦控养面积,使水葫芦在滇池生态治理中发挥更大的作用。     

Electrochemical and spectroscopic characteristics of dissolved organic matter in a forest soil profile

Dissolved organic matter （DOM） represents one of the most mobile and reactive organic compounds in ecosystem and plays an important role in the fate and transport of soil organic pollutants, nutrient cycling and more importantly global climate change. Electrochemical methods were first employed to evaluate DOM redox properties, and spectroscopic approaches were utilized to obtain information concerning its composition and structure. DOM was extracted from a forest soil profile with five horizons. Differential pulse voltammetry indicated that there were more redox-active moieties in the DOM from upper horizons than in that from lower horizons. Cyclic voltammetry further showed that these moieties were reversible in electron transfer. Chronoamperometry was employed to quantify the electron transfer capacity of DOM, including electron acceptor capacity and electron donor capacity, both of which decreased sharply with increasing depth. FT-IR, UV-Vis and fluorescence spectra results suggested that DOM from the upper horizons was enriched with aromatic and humic structures while that from the lower horizons was rich in aliphatic carbon, which supported the findings obtained by electrochemical approaches. Electrochemical approaches combined with spectroscopic methods were applied to evaluate the characteristics of DOM extracted along a forest soil profile. The electrochemical properties of DOM, which can be rapidly and simply obtained, provide insight into the migration and transformation of DOM along a soil profile and will aid in better understanding of the biogeochemical role of DOM in natural environments.     

不同聚硅酸硫酸铁去除有机物及膜污染的影响

采用腐植酸、苯胺、海藻酸钠、羟丙基甲基纤维4种有机物分别模拟天然有机物中的疏水酸性、疏水碱性、亲水带电性及亲水中性4种有机物,使用"聚硅酸+Fe3+"、"聚硅酸+聚硫酸铁(PFS)"、"聚硅酸+Fe2++H2O2"3种不同聚合方式的聚硅酸硫酸铁(PFSS)进行水处理,并将絮凝处理后的废水上清液通过微滤膜,考察不同聚合方式PFSS对有机物的去除及膜污染的影响。实验结果表明:4种有机物最难去除的是苯胺和海藻酸钠,羟丙基甲基纤维素其次,腐殖酸最易去除;以"聚硅酸+PFS""、聚硅酸+Fe2++H2O2"方式聚合的絮凝剂与"聚硅酸+Fe3+"方式聚合的絮凝剂相比,去除产生可逆污染的腐植酸的比例相差不大,但去除产生不可逆污染加大的苯胺、海藻酸钠、羟丙基甲基纤维素3种有机物的比例明显增大,膜污染率虽然相对稍大,但更加可逆。     

湄公河下游国家水质管理状况与区域合作前景

本文分析了老挝、缅甸、泰国、柬埔寨和越南等湄公河下游五国的水质状况及原因,通过汇总湄公河五国的水质管理法律法规及水质标准和介绍各国的水质管理措施,阐述了湄公河国家在水质管理方面做出的努力以及水质管理中存在的问题,并对湄公河国家在流域水质区域合作方面进行了展望。     

原子吸收火焰法次灵敏线测定污水和电镀污泥中高含量的锌

对采用原子吸收火焰法次灵敏线测定污水和电镀污泥中高含量的锌进行了研究。试验结果表明：在锌浓度50．0～600．0mg/L之间,溶液锌含量与吸光度呈线性关系。线性回归方程为y＝0．000661x-0．0007,相关系数γ＝0．9998。方法检出限为25．0mg/L,相对标准误差（RSD）＜2．96％,加标回收率为92．5％～105％,与标准法的相对误差＜2．76％。     

Insertable thin film thermocouples for in situ transient temperature monitoring in ultrasonic metal welding of battery tabs

Real-time monitoring and control of temperature in ultrasonic joining of battery tabs and coupons are important for the quality improvement and cost reduction of battery assembly. However, there have always been difficulties in accurate and real-time measurement of temperature by conventional sensors for practical implementation. In this study, an innovative method is developed to provide an enabling technology for the in situ transient temperature monitoring, which could provide reliable feedback signals for potential control of ultrasonic joining processes. Micro thin film thermocouples (TFTCs) were fabricated on thin silicon substrates, which were then inserted in the welding anvil as a permanent feature so that the sensors were always located about 100 μm directly under the welding spot during joining of multilayer Ni-coated Cu thin sheets for battery assembly. Good repeatability was demonstrated while a temperature rise of up to 650 °C was obtained due to the closeness of the sensors to the welding spot. The inserts with thin film sensors remained functional after welding experiments. This method has a great potential for in situ transient temperature monitoring, and thus the control of ultrasonic joining processes to realize a practical smart joining system.     

浅析化工园区大气特征因子自动监测综合分析

从总体状况评价、浓度变化特征、疑似源探寻等角度初步分析了某化工园区大气特征因子自动监测数据。分析表明,合理选用不同水平的数据集可以突出大气特征因子的规律性,尤其是疑似源探寻;采用现场检查等手段与自动监测的相互校核十分必要,特别是便携式气相色谱质谱仪对特征因子自动监测系统“假阳性”识别。     

浓盐水处理技术研究进展

海水淡化技术是解决中国水资源危机的一种具有根本性的举措之一.然而随着海水淡化产业规模的增大,其产生的浓盐水的排放成了本身面临解决的问题之一.本文阐述了浓盐水的特性及其对环境的各种危害性,并对浓盐水直接排放问题进行了详细分析.介绍了国内外近年来主要处理浓盐水的方法-真空膜蒸馏浓缩技术、正渗透技术、喷雾蒸发技术、冷冻法浓缩技术.对各种处理技术的原理和特点进行了详细综述,并对其研究进展进行了归纳总结.最后对各项处理技术的应用前景提出了展望.     

城市排水系统沉积物特性研究

重点阐述了沉积物的来源和组成,沉积物的颗粒粒径、有机物含量(VSS/SS)、颗粒粘性和颗粒密度等物化性质,以及附着于沉积物上的金属污染物的相关特征。其粒度分布范围是D10为1.89～223.21μm,D50为12.38～437.30μm,D90为39.06～1 572.52μm;VSS/SS的范围是1%～38%;密度范围是1.80～2.47 g/cm3。金属污染物主要的附着对象是沉积物中的细小颗粒如生物膜上。以上沉积物性质对于解决排水系统的泥沙淤积问题以及水体污染的控制都具有重要意义。     

还原法修复六价铬污染土壤的研究

摘要：铬渣中含有毒性较强的六价铬化合物,其严重污染环境。本文通过实验室模拟试验,研究了硫代硫酸钠、亚硫酸钠、抗坏血酸和硫酸亚铁等还原剂对铬渣污染土壤中六价铬的解毒效果。探讨了还原剂的浓度、pH和反应时间对六价铬还原效果的影响。结果表明：亚硫酸钠浓度为1mol／L、pH9．5和反应时间为15min时对六价铬的还原效果最佳。