Non-UV based germicidal activity of metal-doped TiO2 coating on solid surfaces

A stain-based screening method was developed to screen different catalyst coatings for their germicidal activity. A Baclight dead/live bacteria viability kit （invitrogen, molecular probes） was used for staining the cell. The screening was carried out following a standard procedure. This included loading cell suspension to solid surface and maintaining contact for 30 min, then staining with a mixture containing dyes. The stained cells were observed using an epifluorescent microscope and photographed with a CCD camera under UV. Metal-doped TiO2 coatings on AI plates were prepared and tested for non-UV germicidal activity without using UV. It was tested using model microorganisms such as Bakers Yeast （Saccharomyces cerevisiae）, Bacillus subtilis, Pseudomonas putida, and Escherichia coli. On the basis of the germicidal activity of catalyst and the degree of damage caused to the cells, the stained cells may appear green （viable）, green with red or yellow nuclei and yellow （compromised） or red （nonviable）. According to their stained color, cells were counted to calculate the percentage of dead, live, and compromised cells. Compromised cells are cells that grow very slowly after reculturing indicating a degree of reversible cell damage. Screening the germicidal activity using this staining method is accurate and efficient, and requires less time than the culture-based method. A modification to the procedure for measuring germicidal activity of rough surfaces or fibrous coatings was developed. Both TiO2 and metal-doped TiO2 （Ag, Pt, Au, Cu） possess non-UV based germicidal activity. The germicidal activity of TiO2 was found to be related with its wetting property and can be improved by UV irradiation before testing. It is not greatly affected by contact time, indicating a fast acting germicidal activity.     

Effects of chemical modification on physicochemical properties and adsorption behavior of sludge-based activated carbon

This study aimed to explore the adsorption performance of sludge-based activated carbon (SBC) towards dissolved organic matters (DOMs) removal from sewage, and investigated the modification effect of different types of chemicals on the structure of synthesized SBC. Waste activated sludge (WAS) was used as a carbon source, and HCl, HNO₃, and NaOH were used as different types of chemicals to modify the SBC. With the aid of chemical activation, the modified SBC showed higher adsorption performances on DOMs removal with maximum adsorption of 29.05 mg/g and second-order constant (k) of 0.1367 (L/mol/sec) due to the surface elution of ash and minerals by chemicals. The surface elemental composition of MSBC suggested that the content of C-C and C-O functional groups on the surface of modified sludge-based activated carbon (MSBC) played an important role on the adsorption capacities of MSBC towards DOMs removal in sewage. Additionally, the residual molecular weight of DOMs in sewage was investigated using a 3-dimension fluorescence excitation-emission matrix (3D-EEM) and high-performance size exclusion chromatography (HP-SEC). Results showed that the chemical modification significantly improved the adsorption capacity of MSBC on humic acids (HA) and aromatic proteins (APN), and both of NaOH-MSBC and HCl-MSBC were effective for a wide range of different AMW DOMs removal from sewage, while the HNO₃-MSBC exhibited poorly on AMW organics of 2,617 Da and 409 Da due to the reducing content of macropore. In brief, this study provides reference values for the impact of the chemicals of the activation stage before the SBCs application.     

《大气污染防治法(修订草案)》的若干修改建议

《大气污染防治法》(修订草案)有很多突破,但是针对性、策略性、特色性和可实施性均存在欠缺,需要进一步把生态文明、绿色化、区域协同发展的要求纳入立法目的,体现在体制制度和机制的设计中;理顺立法体例,保证规定的逻辑性;坚持空间管控和多规合一,坚持空气质量目标管理的思路,采取实际大气环境容量和实时排放流量控制相结合的工作模式;明确行动计划与现行环境保护规划、各专项环保规划的关系;理顺监管体制,创新区域联合防治的制度和机制,弥补侵权法律责任和法律救济规定的不足,保持信息公开申请和环境民事公益诉讼提起条件的前后贯通性。只有这样,才能既体现立法修改的必要性和针对性,又体现立法规定的时代性和特色性,展现法律措施的严格性和法律责任的严厉性。     

斜发沸石在废水处理中的应用研究进展

天然斜发沸石是一种廉价矿物,经改性后可有效去除废水中氨氮、有机物、重金属离子、砷及放射性物质,并可用作杀菌剂。文章简述了天然斜发沸石的主要改性技术,并着重论述了近年来天然斜发沸石及各种改性斜发沸石在废水处理中的应用研究动态。同时,展望了其应用前景,探讨了目前应用斜发沸石处理废水时仍亟待解决的一些问题。     

SZD/2-1600型组合式电除尘器在西北高寒地区水泥磨上的应用

介绍了SZD/2—1600型组合式静电除尘器的优良性能及特点。通过现场实践与改进,着重介绍了该技术的运用效果及几点体会,意在进一步推广该技术的应用。     

洱海沉积物重金属地球化学相及其污染历史研究

高原封闭、半封闭型湖泊是气候和环境演化的敏感指示器，其沉积物记录具有连续性、敏感性和高分辨率的特点。高原湖泊沉积记录在恢复和重塑各种短时间尺度（千年、百年、十年）的气候和环境演化序列上，具有其它自然历史记录无法替代的优势，尤其在揭示近代环境污染历史方面更有其独到之处。本文通过对洱海沉积物重金属地球化学相的研究，利用因子分析方法，识别了沉积物重金属的主要来源和影响其分布的主要因素，即：流域侵蚀作用、大气沉降作用、工业废水与生活污水的排放，以及早期成岩作用。同时，结合沉积物柱芯210PBex计年结果，本文初步评价了洱海150多年来的重金属污染历史：1958年以来．因为化石燃料使用量的增加．洱海湖区大气污染日趋严重；1982年后，由于西洱河水电站的建成运行和湖区植被的破坏，流域侵蚀作用显著加强，应当引起重视。     

改性PAC的制备及其对染料废水脱色的实验研究

通过用改性絮凝剂对酸性黑210#进行脱色,研究了在改性PAC(引入SO42-)中加入了PAM,改进其絮凝性能的工艺条件.结果表明,改性过程中,改性PAC和PAM的最佳比是240:1,适宜的改性时间和改性温度分别是2 h和50℃.改性产品与市售聚合氯化铝相比,可在较少的投加量时达到较高的脱色率.     

天然植物单宁季铵盐改性絮凝剂的制备和性能评价

用植物单宁和二甲胺、甲醛及环氧氯丙烷进行季铵化反应 ,制得了JK A和JK B两种阳离子絮凝剂。测试了产品的红外光谱 ,并对两种絮凝剂处理效果进行了比较     

Enhanced photo--catalytic activity of gold ion and gold modified

ＩｎｔｒｏｄｕｃｔｉｏｎＴｉＯ2ｐｈｏｔｏｃａｔａｌｙｓｉｓｈａｄｂｅｅｎｔｈｅｆｏｃｕｓｏｆｎｕｍｅｒｏｕｓｉｎｖｅｓｔｉｇａｔｉｏｎｓｉｎｒｅｃｅｎｔｙｅａｒｓ,ｐａｒｔｉｃｕｌａｒｌｙｏｗｉｎｇｔｏｉｔｓａｐｐｌｉｃａｔｉｏｎｆｏｒｔｈｅｃｏｍｐｌｅｔｅｍｉｎｅｒａｌｉｚａｔｉｏｎｏｆｕｎｄｅｓｉｒａｂｌｅｏｒｇａｎｉｃｃｏｎｔａｍｉｎａｎｔｓｔｏＣＯ2,Ｈ2Ｏａｎｄｉｎｏｒｇａｎｉｃｃｏｎｓｔｉｔｕｅｎｔ(Ｈｏｆｆｍａｎｎ,1995).Ｈｏｗｅｖｅｒ,ｐｈｏｔｏｏｘｉｄａｔｉｏｎｗａｓａｌｍｏｓｔｎｏ…     

超声波有机改性凹凸棒土的苯酚吸附性能研究

采用超声波技术,对凹凸棒土进行有机改性,提高凹凸棒土的苯酚吸附能力,比较了不同的阳离子表面活性剂的改性效果,并且通过正交实验得出了超声波改性的最优化工艺条件为：十八烷基三甲基氯化铵的添加比例为35 mmol/100 g,超声波处理时间10 min,屏极电流0.5 A.在此条件下,苯酚去除率可达酸处理凹凸棒土的80倍以上,是搅拌有机改性的1.5倍.