Fly ash reinforced thermoplastic vulcanizates obtained from waste tire powder

Novel thermoplastic composites made from two major industrial and consumer wastes, fly ash and waste tire powder, have been developed. The effect of increasing fly ash loadings on performance characteristics such as tensile strength, thermal, dynamic mechanical and magnetic properties has been investigated. The morphology of the blends shows that fly ash particles have more affinity and adhesion towards the rubbery phase when compared to the plastic phase. The fracture surface of the composites shows extensive debonding of fly ash particles. Thermal analysis of the composites shows a progressive increase in activation energy with increase in fly ash loadings. Additionally, morphological studies of the ash residue after 90% thermal degradation shows extensive changes occurring in both the polymer and filler phases. The processing ability of the thermoplastics has been carried out in a Monsanto processability testing machine as a function of shear rate and temperature. Shear thinning behavior, typical of particulate polymer systems, has been observed irrespective of the testing temperatures. Magnetic properties and percolation behavior of the composites have also been evaluated.     

粉煤灰制聚合氯化铝铁和白碳黑新工艺

采用粉煤灰制备聚合氯化铝铁和白碳黑.该法共分一次酸浸、碱溶、焙烧、二次酸浸4个阶段.实验确定的最佳工艺条件为:一次酸浸阶段酸溶温度100℃,碱溶阶段m(氢氧化钠):m(活化高硅渣)=0.6,二次酸浸阶段m(碳酸钠):m(灰渣A)=0.8、盐酸质量分数20%.在此条件下Fe~(3+)和Al~(3+)的总浸出率分别为96.54%和86.67%.主要产品聚合氯化铝铁的质量符合GB15892-2003<水处理剂聚氯化铝>的标准;产品白碳黑的质量符合GBl0517-89<沉淀二氧化硅>的标准.     

铁屑内电解法处理电镀含铬废水的实验研究及应用

详细介绍了铁屑内电解法处理技术的基本原理,同时就该法对六价铬去除率的影响因素：停留时间、pH值、铁炭比和铁屑粒径进行了动态试验,得到了较佳工艺参数,并成功应用于工程实例。结果表明：用铁屑内电解+斜管沉淀池+微孔过滤机处理电镀含铬废水,Cr(Ⅵ)的去除率达到99.6%以上,出水各监测指标优于国家《污水综合排放标准》（GB8978-1996）一级排放标准。实践证明该工艺投资少,处理成本低,运行简单,效果好。     

Are non‐poor households always less vulnerable? The case of households exposed to protracted civil war in Southern Sudan

Civil wars in Africa are now the leading contributory cause of vulnerability of rural communities. Understanding vulnerability during civil war is critical for humanitarian response and post-conflict rehabilitation planning. The lack of understanding of vulnerability has led existing studies to make sweeping generalizations, either by equating the dynamics of vulnerability during civil wars with vulnerability in other risk events, or by projecting people in the 'war zones' as unable to cope and subsequently becoming vulnerable. This paper is an attempt to gain a more nuanced understanding of the dynamics of vulnerability during protracted civil war. It shows that during civil war the non-poor are not necessarily less vulnerable than poor households. The idea that people caught up in civil war are all vulnerable is not supported by the findings of this paper. It shows that the 'standard' pattern of vulnerability to drought is similar to that during exogenous counter-insurgency warfare, while a different pattern of vulnerability to endogenous shocks is identified.     

BAF处理生活污水过程中同步去除H2S的试验研究

采用曝气生物滤池处理生活污水的过程中,以混和臭气的空气为气源,以掺入了陶粒和铁炭颗粒的复合填料为载体,研究了反应器的运行条件和参数,结果表明,以混合臭气的空气作为气源对污水处理过程的需氧量基本无影响.当反应器的进气量为40 L/h,进水容积负荷和进气H2S的浓度分别在0.3～1.6 kg COD/(m3·d)和0.8～2.3 mg/m3之间变化时,可以实现出气和出水中H2S和COD分别小于0.04 mg/m3和90 mg/L,满足同时达标排放的要求.H2S的同步去除可能是通过微生物的氧化分解和形成FeS沉淀来实现的.     

生活垃圾渗滤液对厌氧颗粒污泥产甲烷活性的影响研究

通过厌氧毒性实验、恢复实验和特征毒性模拟实验,研究了生活垃圾渗滤液对厌氧颗粒污泥微生物产甲烷活性的影响。结果表明,1 000 mg/L氨氮浓度下产甲烷活性均大于85%,说明相应氨氮浓度范围,垃圾渗滤液基质对厌氧颗粒污泥的微生物没有明显抑制作用。恢复实验后活性得到完全恢复,属代谢毒性。模拟废水氨氮浓度大于1 000 mg/L浓度时,开始出现抑制;氨氮浓度大于3 000 mg/L时,有明显抑制,产甲烷活性下降32.1%;相同氨氮浓度下,渗滤液最大活性区间滞后于模拟废水,产甲烷活性也小于模拟废水,存在除氨氮以外的毒性物质的影响。     

Ce3+对好氧颗粒污泥培养的影响

研究了Ce3+对好氧颗粒污泥形成的影响。实验结果表明:在Ce3+质量浓度为10.0mg/L时,Ce3+对微生物的刺激作用最大,对改善污泥性能具有明显的促进作用;运行45d后,投加Ce3+的SBR的COD去除率和未投加Ce3+的SBR的COD去除率分别为97.5%和95.3%,TP去除率分别为95.6%和62.3%,TN去除率相差不大,均高于76.0%。     

基于随机化Pushover的结构整体抗震可靠度参数分析

为了研究使用随机化Pushover方法进行RC框架结构整体抗震可靠度计算过程中相关参数的适应性,使用Matlab调用SAP2000编制出基于随机化Pushover的结构整体抗震可靠度程序,以一榀11层RC框架结构为例,通过该程序统计出不同参数下结构最大层间位移角的分布情况及整体失效概率,并以大样本实际地震波进行时程分析所统计出的相应结果为基准进行对比。结果表明,在常规参数设置下随机化Pushover方法统计出的最大层间位移角分布情况和结构整体失效概率与大样本时程分析结果有较大差异,然后提出了一种修正方式,有效地减小了两者的差异,并以某算例验证了该修正方式的适用性。     

火焰原子吸收法测定废水中的钴

研究采用硝酸-高氯酸消解样品,用火焰原子吸收分光光度法测定废水中钴的方法.通过标准样品和实验样品的分析,验证了方法的准确度和精密度.方法的加标回收率为94.0％ ～ 108.0％,检出限为0.010mg/L.该方法简单可靠,干扰少,适合废水分析.     

Perchlorate removal using granular activated carbon supported iron compounds: Synthesis, characterization and reactivity

Synthesis and use of the iron compounds supported on granular activated carbon (ICs/GAC) have shown significant environmental implications for perchlorate (ClO 4 ) removal. ICs/GAC was synthesized via hydrolyzing FeSO 4 ·7H 2 O on GAC, reduced by NaBH 4 solution in polyethylene glycol 6000 and ethanol solution, dried in vacuum condition and exposed to air. Synthesized ICs/GAC was characterized using transmission electron micrograph (TEM), Brunauer-Emmett-Teller, X-ray photoelectron spectroscopy (XPS). ICs/GAC was determined to be containing a large amount of FeOHSO 4 , Fe 2 O 3 and a small amount of zero-valent iron (ZVI) nanoparticles according to TEM and XPS measurements. Batch static kinetic tests showed that 97% of ClO 4 was removed within 10 hr at 90°C and 86% of ClO 4 was removed within 12 hr at 25°C, at ICs/GAC dosage of 20 g/L. The experimental results also showed that FeOHSO 4 and Fe 2 O 3 nanoparticles have the function of perchlorate adsorption and play important roles in ClO 4 removal. The activation energy (E a ) was determined to be 9.56 kJ/mol.