三峡库区高边坡紫色土抗剪强度的水敏性特征∗

为了研究高边坡紫色土的抗剪强度及变形随含水率的变化规律,在不同围压下对不同含水率的非饱和重塑紫色土进行了固结不排水三轴试验。结果表明：在不同的含水率及围压条件下,土体应力-应变关系曲线均呈现出“持续硬化”甚至“加速硬化”现象。其应力-应变关系曲线经历了3个阶段：轴向应变0%~2.3%为弹性阶段,2.3%~4%为应变硬化阶段,4%后逐渐变为屈服阶段。在同一围压下,土体主应力差峰值随含水率的增加而降低,其峰值下降幅度最大可达67.37%。不同含水率下的最大主应力差与围压均表现出较好的线性关系。在给定含水率下,主应力差峰值随围压的增加而明显增大,其峰值增大幅度最大可达150.98%,但随着含水率的升高,这种增大趋势逐渐减小,且围压对紫色土抗剪强度影响约为含水率对其影响的66.63%。随着含水率的增加,土壤的内聚力先增加后减小,峰值处的含水率为12%;而土壤的内摩擦角随含水率的增加呈现一阶线性减小,且下降程度最大可达56.88%。土体任意平面(破坏面)上σ-τ曲线的斜率随着含水率的增加而逐渐减小,而破坏包面逐渐变缓。分析并讨论了含水率对紫色土内部结构、颗粒间作用力及特性的影响,以期为三峡库区高边坡紫色土的综合治理提供理论支持和技术支撑。     

撞击流反应器萃取电镀废水中Cr6+的实验研究

以磷酸三丁酯（TBP）为萃取剂,用撞击流反应器对模拟含铬电镀废水中的Cr^6＋进行了萃取脱除实验研究。与相同条件下的传统单级化学萃取相比,撞击流反应器利用两喷嘴的射流作用在两流体相对撞击时获得高效传质区域,能有效强化液液萃取的相际传质过程,其单级萃取率最多可提高20．11％。当萃取剂中TBP的体积分数为10％、相比（有机相与水相的体积比）为1：2、萃取时间为1min、H^＋的浓度为1．0mol／L时,通过实验得出适宜的操作条件为：喷嘴间距离为喷嘴直径的3．4倍,搅拌转速600r／min,萃取温度30—40℃,在此条件下Cr^6＋的萃取率为31．5％。     

超声波处理剩余活性污泥促进厌氧消化

用超声波处理剩余活性污泥(简称污泥),考察了污泥絮体结构、污泥中溶解性化学需氧量(SCOD)的变化规律及超声波处理对污泥厌氧消化的影响。实验结果表明,声强大于1 040W/m2时,用超声波处理污泥30m in以上,污泥絮体被打碎,污泥絮体结构遭到严重破坏,污泥中SCOD迅速增加,加速了污泥中有机质的水解反应;声强为2 000W/m2时,用超声波处理污泥60m in,中温((37±1)℃)厌氧消化10d,COD去除率为41%;厌氧消化25d的总产气量比未经超声波处理的污泥总产气量提高了53%;将发酵罐容积放大10倍,经超声波处理的污泥25d累积的总产气量比未经超声波处理的污泥总产气量提高了约25%。     

Local and regional air pollution in Ireland during an intensive aerosol measurement campaign

An intensive two month measurement campaign has been performed during a two year study of major component composition of urban PM10 and PM2.5 in Ireland (J. Yin, A. G. Allen, R. M. Harrison, S. G. Jennings, E. Wright, M. Fitzpatrick, T. Healy, E. Barry, D. Ceburnis and D. McCusker, Atmos. Res., 2005, 78(3-4), 149-165). Measurements included size-segregated mass, soluble ions, elemental carbon (EC) distributions, fine and coarse fraction organic carbon (OC) and major gases along with standard meteorological measurements. The study revealed that urban emissions in Ireland had mainly a local character and therefore were confined within a limited area of 20-30 km radius, without significantly affecting regional air quality. Gaseous measurements have shown that urban emissions in Ireland had clear, but fairly limited influence on the regional air quality due to favorable mixing conditions at higher wind speeds, in particular from the western sector. Size-segregated mass and chemical measurements revealed a clear demarcation size between accumulation and coarse modes at about 0.8 microm which was constant at all sites. Carbonaceous compounds at the urban site accounted for up to 90% of the particle mass in a size range of 0.066-0.61 microm. Nss SO4(2-) concentrations in PM2.5 were only slightly higher at the urban site compared to the rural or coastal sites, while NO3- and NH4+ concentrations were similar at the urban and coastal sites, but were a factor of 2 to 3 higher than at the rural site. OC was highly variable between the sites and revealed clear seasonal differences. Natural or biogenic OC component accounted for <10% in winter and up to 30% in summer of the PM2.5 OC at urban sites. A contribution of biogenic OC component to PM2.5 OC mass at rural site was dominant.     

应用水解+A/O工艺治理化工废水的工程实践

兰州石化公司应用水解(酸化)+AO工艺组合治理化工废水。化工废水经水解(酸化)处理后,BOD5CODCr比值从<0.2提高到0.37,提高了化工废水的可生化性。该工艺利用兼氧和好氧微生物对高浓度化工废水处理后,CODCr的去除率达85%以上,NH3N的去除率达95%以上。     

射阳河底泥重金属沿程变化分析及污染评价

分析了射阳河流域沿程20个底泥样品中6种重金属(Cr、Pb、Ni、Zn、Cu、As)的含量,并应用地累积指数法对其进行了污染评价。研究结果表明:除As在近一半的采样点没有污染,其他重金属污染均普遍存在,但多数属于轻度污染。Zn污染最为严重,几乎全程都是偏中等或中等以上的污染。纵观射阳河全程样品FN04,SY07污染最为严重,前者与其支流西塘河的污染有关,后者可能与河闸上侧的死水状态有关;黄沙河污染最轻,与河流沉积物粒径比较粗而导致的对重金属吸附能力减弱有关。     

城市污水处理厂除臭技术

介绍了城市污水处理厂臭气来源、成分及产量.针对目前国内外除臭技术的研究和发展情况,分析了污水处理厂的各种物理、化学和生物除臭方法的技术原理、优缺点和应用现状.结合日本城市污水处理厂的运行实际,重点介绍了一种不产生臭气的新技术--腐殖活性污泥法的工艺流程、特点及其应用现状.     

2-羟基-5-磺酸基苯基重氮氨基偶氮苯光度法测定微量Ni(Ⅱ)的研究

2—羟基— 5—磺酸基苯基重氮氨基偶氮苯与 Ni( )在 OP存在下 ,于 p H=1 0的硼砂缓冲溶液中形成 2∶ 1红色络合物 ,λmax=530 nm,ε=6.0× 1 0 4 L· mol- 1·cm- 1 ,Ni( )含量在 0～ 0 .2 4 mg/ L符合比耳定律。用于电镀废水中镍的测定 ,结果满意。     

昆明滇池砷形态分布研究

采用离子交换和溶剂萃取相结合的分离;富集技术,事等离子体发射光谱仪（ＩＣＰ－ＡＥＳ）测定,对昆明滇池７个取样点的砷形态进行了分离和必滇池环境对池中砷形态的迁移转化进行了探讨,为滇池砷污染的研究和治理提供了一定依据。     

A docking-based receptor library of antibiotics and its novel application in predicting chronic mixture toxicity for environmental risk assessment

As organisms are typically exposed to chemical mixtures over long periods of time, chronic mixture toxicity is the best way to perform an environmental risk assessment (ERA). However, it is difficult to obtain the chronic mixture toxicity data due to the high expense and the complexity of the data acquisition method. Therefore, an approach was proposed in this study to predict chronic mixture toxicity. The acute (15 min exposure) and chronic (24 h exposure) toxicity of eight antibiotics and trimethoprim to Vibrio fischeri were determined in both single and binary mixtures. The results indicated that the risk quotients (RQs) of antibiotics should be based on the chronic mixture toxicity. To predict the chronic mixture toxicity, a docking-based receptor library of antibiotics and the receptor-library-based quantitative structure–activity relationship (QSAR) model were developed. Application of the developed QSAR model to the ERA of antibiotic mixtures demonstrated that there was a close affinity between RQs based on the observed chronic toxicity and the corresponding RQs based on the predicted data. The average coefficients of variations were 46.26 and 34.93 % and the determination coefficients (R ²) were 0.999 and 0.998 for the low concentration group and the high concentration group, respectively. This result convinced us that the receptor library would be a promising tool for predicting the chronic mixture toxicity of antibiotics and that it can be further applied in ERA.