SiO_3~(2-)离子的加入对脉冲倒极电解合成PASiC的研究

探索了试验过程中SiO2 -3 离子团的加入对脉冲自动倒极电解法合成聚合氯化硅酸铝中Alb 含量的影响。通过试验确定了最佳摩尔比。在脉冲倒极周期和电解槽电流一定的情况下 ,当总铝AlT 与SiO2 -3 的摩尔比为 10∶1～ 2 0∶1时 ;在此合成条件下制备液中Alb 含量超过 80 % ;处理模拟水样最佳投药量为 :0 5～ 5mgAl2 O3 /L。在制备过程中 ,极化现象得到了极好的控制 ,电解槽电压和电流十分稳定     

苯胺废水处理技术研究进展

综述了有毒、难生物降解废水———苯胺废水的各种处理技术及基本原理 ,这些处理技术主要包括物理、化学、生物等方法     

新型沸石填料间歇硝化反应器的研究

介绍一种新型沸石填料 ,用于提高生物脱氮系统中硝化反应器的硝化性能。试验结果表明 ,应用了沸石填料的硝化反应器的硝化性能得到了显著提高 ,在脱氮效率和速率上 ,与普通生物载体硝化反应器相比具有明显的优势。硝化反应器连续运行 17d ,出水氨氮基本在 1mg/L以下 ,氨氮去除率在 97%以上。该系统停止运行 5 0d后再次启动 ,一周内硝化性能得以恢复     

复合混凝剂处理染料废水的研究

分析酸性大红染料的结构与特点 ,进行各种混凝剂的筛选实验 ,配制FeSO4 MgSO4 Ca(OH) 2 PAM复合混凝剂 ,并通过实验优化操作条件 ,实验结果表明 ,对COD =2 88.3mg/L、色度为 2 5 0 0 0倍的酸性大红GR实验废水 ,COD去除率可高达 85 .3% ,最高脱色率可达 97.4 % ,在脱色率达 90 %时 ,药剂费用为 1.12元 /t。     

生物强化系统微生物分子诊断技术的应用及新发展

现代分子生物技术的飞速发展及其在环境研究领域的应用，为生物强化技术的研究和发展提供了新方法和新思路。本文从生物强化系统特异微生物检测及定量化技术、生物强化系统微生物群落结构组成及动态演替规律研究、生物强化作用机制的分子生物学解析、生物强化菌的基因工程构建、生物强化系统微生物的安全释放及控制技术几方面，对生物强化系统微生物分子诊断技术的应用和发展作了较为全面的综述。     

环境中氧化锰对Cr(Ⅲ)氧化机理的研究

研究了几种人工合成的氧化锰和新鲜田间土样对Cr(Ⅲ)的氧化作用.结果表明,自然土壤环境中,氧化锰是Cr(Ⅲ)氧化的主要电子接受体,氧化能力δ-MnO_2>α-MnO_2>γ-MnOOH.土壤对Cr(Ⅲ)氧化能力与易还原性氧化锰含量显著相关.土壤风干后,氧化Cr(Ⅲ)的能力明显降低.并提出了Cr(Ⅲ)在MnO_2表面氧化的机理.     

环磷酰胺等三种化学物诱发褐斑大蠊染色体畸变分析

染色体的畸变分析是一种简便易行,经济的遗传毒理学方法,可用来探讨诱变物对生物遗传系统的影响。目前人们多利用鼠类、赤麂及人的培养细胞来进行染色体畸变分析,其它材料很少见,蜚蠊(俗称蟑螂)是一种重要的卫生昆虫,也是一种较好的遗传学研究材料,其分布广泛,与人的日常生活环境密切相关,能否利用它作为一种污染的监测因子呢?我们利用褐斑大蠊(Periplaneta brunnea,Burmeister 1838)进行了初步尝试。     

某电厂堆灰场附近浅层地下水中Cr6+的成因及治理措施

分析了焦作某电厂堆灰场附近浅层地下水中Cr6+ 的形成原因。根据该区水文地质背景 ,提出在地下污染水羽的下游建可渗透反应墙的漏斗 -通道系统 ,用对Cr6+ 有很高去除效率的风化煤作为反应材料 ,使污染水羽流经此系统时有效去除地下水中的Cr6+ ,达到净化的目的     

Effect of cadmium on nodulation and N2-fixation of soybean in contaminated soils

The effects of cadmium stress on nodulation, N2-fixation capabilities of the root nodule, the change in ultrastructure of the root nodule, soybean growth, and the distribution of cadmium in plants were studied. The results obtained show that the nodulation of soybean roots was greatly inhibited by the addition of Cd, especially at the addition level of 10 and 20 mg kg(-1) soil. The inhibition of plant growth, especially the root growth, increased as the cadmium concentration increased, with deleterious effects observed for the roots. The weight ratio of soybean root/leaf decreased as the Cd concentration increased, which might explain the reason for nodulation decreases. The results also indicate that N2-fixation of root nodule was stimulated to some extent at the low levels of Cd addition, but decreased sharply with further increase of the Cd concentration. High Cd levels were also associated with changes in the ultrastructure of root nodule, in which the effective N2-fixing area was reduced and the N2-fixing cells in the area also reduced. In addition, the results also reveal that the content of Cd in different parts of the plants was as follows: roots > stems > seeds, indicating that the accumulation of Cd by roots is much larger than that by any other part of the soybean plant, and might cause deleterious effects to root systems.     

Longitudinal emissions evaluation of mixed (cooperative) adaptive cruise control traffic flow and its relationship with stability

ABSTRACT

Cooperative adaptive cruise control (CACC) vehicles need vehicle-to-vehicle (V2 V) communication to achieve CACC function. When a CACC vehicle follows a manual-driven vehicle (MDV) without V2 V communication, it needs degenerate to adaptive cruise control (ACC). By using real experiments, California PATH program indicated that ACC vehicles are apt to be unstable, which may have negative influence on fuel consumption and traffic emissions. Hence, this paper studies the impacts of the mixed CACC-MDV traffic on fuel consumption and emissions, by taking into consideration partial degenerations from stable CACC vehicles to unstable ACC vehicles. To deal with this, microscopic simulations were adopted by using car-following models. Then, an appropriate emission model was used for evaluating the emission impacts under different CACC market penetration rates (MPRs). In order to obtain reliable evaluation results, the models validated by PATH program using real experimental data were employed as the CACC and ACC car-following models. In addition, we also analytically investigated stability of the mixed traffic flow under different CACC MPRs, in order to explore its relationship with the emission impacts. The results show that the fuel consumption and emissions firstly increase and then decrease with the increase of the CACC MPR. This means the mixed traffic under some ranges of CACC MPRs will produce more fuel consumption and emissions, compared with the full MDVs traffic. It indicates that stability situations of the mixed traffic qualitatively influence the impact trend of CACC MPRs on fuel consumption and emissions. Then, V2 V communication equipments on MDVs are not only encouraging but also essential to avoid the deterioration of fuel consumption and emissions of the mixed traffic flow.