汽车尾气净化催化剂涂层改性研究

汽车尾气净化催化剂的净化转化效果及其耐久性，与催化剂涂层的涂覆量以及涂层和载体的结合强度密切相关。本文研究了几种不同类型表面活性剂对浆料固体含量、涂层涂覆量以及涂层结合强度的影响。研究结果表明，不使用表面活性剂时，30％为最佳的固体含量；在使用表面活性剂的情况下，浆料的固体含量可以提高至35％。非离子型表面活性剂有助于提高催化剂涂层涂覆量，而使用离子型表面活性剂的浆料球磨过程中产生大量泡沫，无法涂覆。使用非离子型表面活性剂的催化剂涂层的结合强度最好。     

The influence of untreated wastewater to aquatic communities in the Balatuin River,The Philippines

A risk assessment of chemical constituents in rivers that receive untreated wastewater should take into account the adverse effects of increased biological oxygen demand (BOD), ammonia and reduced dissolved oxygen (DO). This concept was tested via a field study in the Balatuin River, The Philippines, where the influence of physical and chemical factors, including the consumer product chemical linear alkylbenezene sulfonate (LAS), to aquatic communities (algae, invertebrates, fish) was determined. Periphytic algae were found to be insensitive to high BOD (>10 mg/l) and ammonia (>0.01 mg unionized NH(3)/l), concentrations from organically enriched untreated wastewater discharges. However, taxa richness and abundance of macroinvertebrates were influenced greatly by the discharges. Where BOD and ammonia concentrations were elevated, the dominant taxa were oligochaete worms and chironominds. Fish and crustaceans (freshwater crabs and prawns) were found only in sites with the least BOD concentrations (furthest upstream and downstream). The maximum concentration of LAS (0.122 mg/l) was less than that expected to affect 5% of taxa (0.245 mg/l), whereas exceedences of DO and ammonia criteria were observed in several sites. The lack of recovery observed was attributed to influences of low DO, high ammonia and poor colonization from upstream and downstream reaches due to organically-enriched discharges     

酸解破乳作用处理高含固率洗毛废水的研究

洗毛废水是一种高浓度有机废水,含固率高,主要成分是羊毛脂、羧酸盐和土杂,由于强极性物质的存在和胶体强的负电性,导致洗毛废水形成稳定的乳化体系.本试验通过加入硫酸改变洗毛废水的有机组成,降低体系的Zeta电位,破坏体系的稳定性,从而使得有机物发生凝聚沉降,达到去除COD的目的.硫酸加入量达到0.2%或以上时对洗毛废水中SS的自然沉降性、絮凝性和极性有很大影响,比阻从远大于9.81×1013m/kg,下降为5.54×1010m/kg,COD去除率达到86.8%,SS去除率达到98%.因此,洗毛废水加酸处理后通过机械脱水,实现固液分离,以降低原废水的色度和大幅降低COD的方式,是可供考虑的处理工艺.     

Control of NOx emissions by air staging in small- and medium-scale biomass pellet boilers

Environmental Science and Pollution Research - The effect of air staging strategies on NOx control was investigated on a 210-kW small-scale biomass boiler (SBB) and a 1.4-MW medium-scale biomass...     

Comparison of different sequential extraction procedures for mercury fractionation in polluted soils

Environmental Science and Pollution Research - Three sequential extraction procedures (SEPs), modified Tessier, modified BCR, and CIEMAT, were compared for mercury fractionation in polluted soils....     

Air pollution inequality and health inequality in China: An empirical study

Environmental Science and Pollution Research - China’s residents experience unequal exposure to air pollution in different regions, and the corresponding health consequences have increased...     

The associations of air pollution exposure during pregnancy with fetal growth and anthropometric measurements at birth: a systematic review and meta-analysis

Environmental Science and Pollution Research - Fetal growth has been demonstrated to be an important predictor of perinatal and postnatal health. Although the effects of maternal exposure to air...     

三维多孔碳海绵催化臭氧氧化有机染料

针对目前催化臭氧氧化催化剂效率较低、易损失等缺点,通过高温煅烧制备了三聚氰胺碳海绵,以廉价易得的三聚氰胺泡沫直接碳化制备出柔性碳海绵,探讨其在催化臭氧氧化降解印染废水反应中的应用潜力;采用SEM观察、比表面积测定、傅里叶红外光谱和X-射线光电子能谱对碳化前后泡沫进行了表征,探讨了碳化前后泡沫微观结构的变化与催化降解印染废水性能与机理。结果表明：氮气氛围下高温煅烧获得了兼具微孔/介孔结构的三维碳骨架,为催化反应提供充分暴露的活性位点和高效的传质通道;在催化臭氧氧化染料的过程中,973 K下制备的碳泡沫呈现出最为优异的催化活性,显著高于均相臭氧氧化和常规活性炭催化臭氧氧化;自由基捕获实验表明催化过程由羟基自由基(·OH)所主导,超氧自由基(·O₂^-)则发挥了次要作用;富含多孔结构的碳海绵对于活性自由基的生成起到了积极贡献,从而在实际印染废水处理中具有良好的降解性能。研究为开发低成本的三维碳材料用于催化臭氧降解有机污染废水提供了新思路。     

中位粒径对线管式静电除尘器内PM2.5除尘性能影响的数值模拟

以线管式静电除尘器为研究对象,利用Fluent数值模拟了离子风和外加磁场作用下中位粒径对静电除尘器（ESP）除尘性能的影响。数值结果表明：ESP对PM2.5除尘效率随中位粒径的增大呈增大的趋势,离子风和外加磁场效应均能提高ESP的除尘效率,联合作用更为明显,可为未来的ESP优化设计提供指导。     

臭氧-过硫酸盐工艺深度处理垃圾焚烧渗沥液

针对垃圾焚烧渗沥液经"厌氧-缺氧-好氧"生物组合工艺处理后的出水COD仍在500 mg·L-1左右,且可生化性差（B/C=0.13）的问题,研究采用"臭氧-过硫酸盐"氧化体系进一步处理,以提高其可生化性。研究了臭氧和过硫酸盐投量对该废水处理的效果影响。结果表明,臭氧浓度和S2O2-8浓度分别为19.8 g·m-3和0.4 g·L-1时,且反应20 min,出水的B/C从0.13提高到0.49,表明该氧化体系适用于深度处理垃圾焚烧渗沥液生物组合工艺处理后的出水。采用紫外-可见光谱、三维荧光光谱、红外光谱和气质联用对处理系统废水中有机物进行表征分析,表明废水在"臭氧-过硫酸盐"氧化过程中芳香族化合物发生了开环、断链等反应,芳构化程度降低,不饱和的CC键被破坏,产生CO和C—O键,并生成一些结构简单的长链烷烃。自由基捕获研究表明,氧化体系中·OH和·SO4- 2种自由基均存在,以臭氧直接氧化为主。