WO3/TiO2复合半导体的光催化性能研究

采用Ｓｏｌ－Ｇｅｌ法制备ＷＯ３／ＴｉＯ２纳米粉末,以高压汞灯为光源,亚甲基蓝溶液的光催降为模型反应,结果表明,掺入ＷＯ３摩尔比为２％时,ＷＯ３／ＴｉＯ２的光活性最高;随着热处理温升高,ＷＯ３／ＴｉＯ光活性增强;     

城市规划的环境影响评价研究初探

环境影响评价法的颁布是中国环境影响评价的一个新阶段。中国至今尚无明确的、系统的规划环境影响评价的技术导则和规范,其评价理论仍在探索之中。分析了国内外规划环境影响评价的历史和现状。从区域环境影响评价的实践经验总结出了城市规划环境影响评价应强调城市发展的可持续性。探讨了该层次评价的介入时间、评价原则、环境影响因素识别及评价内容,提出从生态合理性、绿色化程度等方面考虑城市规划的生态环境影响。     

浙江省沿海地区农村房屋抗风情况调研

对浙江省沿海地区的农村房屋抗风情况进行了调研,总结了被破坏房屋的主要结构特点。在对现有房屋的统计中发现相对不富裕地区高达60%以上的房屋属于抗风能力差和较差的,而一些比较富裕且受过台风袭击有过惨痛教训地区的房屋抗风能力差和较差的仅在20%以下。进一步研究发现抗风能力较好的房屋大都是建造年代不久,多为混凝土现浇板屋盖,上部多为框架或砖混结构,而抗风能力较差和差的大都为建造年代已久,多为小青瓦屋面,上部结构多为砖木结构或构造措施较差的砖混结构。同时对当地村民传统的"砖头压瓦"防护措施进行理论验算,得出当风速超过台风界限风速时,屋面上的砖头将会飞起,该措施应该避免。     

软土地区型钢水泥土搅拌墙墙土相互作用试验研究

软土地区采用型钢水泥土搅拌墙(SMW工法)支护形式优势非常明显,但目前对SMW工法墙-土相互作用机理的研究不够透彻,制约了其推广与应用。为深入探索墙-土相互作用机理,针对软土地区SMW工法建立了大比尺试验模型,对各工况墙顶位移、墙侧土压力以及型钢应变进行了测试。试验结果表明:SMW工法墙顶位移速率变化随基坑挖深增加呈U型趋势,而位移呈S型发展,位移时间效应显著,挡墙存在明显的最优嵌固比;实测墙背主动土压力呈抛物线型分布,基坑墙体位移值和位移速率均影响极限土压力发展,实测极限主动土压力大小间于Rankine主动土压力和静止土压力之间,而实测极限被动土压力远小于理论值;水泥土和型钢的组合挡墙承载能力和刚度明显优于型钢,且二者变形协同性较好,建议在SMW工法支护结构设计时考虑水泥土对组合挡墙的刚度贡献。     

生态县评价体系及持续发展战略的研究

在生态县规划研究中,以复合生态系统理论为指南,探讨了生态县的内涵和评价标体系,并确定了以生态农业为基础,以生态型工业为主导,以社会调控为保障,依靠科技进步,寓环境建设于经济社会发展之中的建设生态县的战略,在近年实践中初见成效。     

Comparison of metabolome profiles in zebrafish (Danio rerio) intestine induced by polystyrene microplastics with different sizes

Environmental Science and Pollution Research - Microplastics (MPs) are widespread in aquatic environments. They could induce intestinal toxicity in the fish. However, research on the metabolic...     

PSAT和BPA在电力系统潮流计算中的对比研究

针对当前电力系统分析程序存在差异的问题,从潮流计算角度,对比研究了国内目前使用较为普遍的2款潮流计算程序(PSAT和PSD-BPA),分析了收敛误差、发电机分接头、负荷比例等不同初值条件设置对其潮流计算结果的影响。分析结果表明:PSAT在建模、可视化和自定义方面具有一定优势,比较适合小规模电网仿真和自定义元件模型研究;而BPA的计算速度快,计算精度高,比较适合大规模电网仿真。     

钢铁行业废水零排放技术探索

针对钢铁行业废水特点,分析了目前钢铁行业各工序及全厂主要废水污染控制措施,重点分析了二级反渗透工艺的主要流程及进出水水质,以及该工艺存在的主要问题。通过对大型钢铁集团的现场调研,以太钢采用的反渗透和蒸发结晶工艺为例分析了钢铁行业真正实现废水零排放的技术可行性。该技术可以很好解决钢铁行业浓盐水的外排问题。     

A red water occurrence in drinking water distribution systems caused by changes in water source in Beijing,China: mechanism analysis and control measures

A red water phenomenon occurred in several communities few days after the change of water source in Beijing, China in 2008. In this study, the origin of this problem, the mechanism of iron release and various control measures were investigated. The results indicated that a significant increase in sulphate concentration as a result of the new water source was the cause of the red water phenomenon. The mechanism of iron release was found that the high-concentration sulphate in the new water source disrupted the stable shell of scale on the inner pipe and led to the release of iron compounds. Experiments showed that the iron release rate in the new source water within pipe section was over 11-fold higher than that occurring within the local source water. The recovery of tap water quality lasted several months despite ameliora- tive measures being implemented, including adding phosphate, reducing the overall proportion of the new water source, elevating the pH and alkalinity, and utilizing free chlorine as a disinfectant instead of chloramine. Adding phosphate was more effective and more practical than the other measures. The iron release rate was decreased after the addition of 1.5 mg. L-1 orthophosphate- P, tripolyphosphate-P and hexametaphosphate-P by 68%, 83% and 87%, respectively. Elevating the pH and alkalinity also reduced the iron release rate by 50%. However, the iron release rate did not decreased after replacing chloramine by 0.5-0.8 mg. L-1 of free chlorine as disinfectant.