贵阳市表层土壤中镉的环境地球化学基线研究

以土壤环境地球化学研究为主线,以贵州省贵阳市8　046　km²为研究区域,将土壤重金属污染元素镉的空间分布规律与环境地球化学机理研究相结合,建立区域土壤环境地球化学基线,选用合适的判别指标判识自然作用过程与人类活动过程对土壤环境的影响.通过对487个样品的镉含量的统计分析,结果表明,贵阳市表层土壤中镉的基线值为0.068　mg/kg,镉元素含量大于1.010　mg/kg的样品可能遭受人为污染的影响.地质累积指数分析结果显示,贵阳市40%的表层土壤未受镉污染,19%的表层土壤在无污染与中度污染之间,14%受中度污染,19%的表层土壤介于中度污染到强污染之间,7%受强污染,1%的表层土壤介于强污染到极强污染之间.污染程度指数分析则显示,贵阳市57.9%的表层土壤未受到镉污染,镉的污染程度最大为12.1,96%的表层土壤污染程度小于4,总污染程度大于0,即总体受到污染.     

臭气(恶臭)的测定与气味传感器

由于"气味"具有芳香(香味)和恶臭(臭味)等多种多样的特征,所以很难用同一尺度进行评价。因此,进行气味评价(量化)时,需要在明确目的的基础之上,选择适当的评价方法。在此对恶臭的相关测定方法以及在企业等现场进行自主管理时使用的简易测定方法,气味传感器(恶臭测试仪)的使用事例进行介绍。     

西藏昌都地区土地利用结构熵值时序分析

研究土地利用结构的变化反映了区域发展和人类活动的强度,是研究区域发展结构的核心内容之一。区域土地利用结构的变化是区域土地利用演变的直接体现,信息熵可以作为土地利用结构有序性的一种度量。借助信息熵理论对藏东地区1992~2004年土地利用结构熵进行了计算与分析,分析结果表明：研究区土地利用结构熵2004年较1992年有所增加,但是增长幅度较小,与全国和西部地区土地利用信息熵水平相比,藏东地区土地利用系统结构熵值较低,有序度较高。土地利用结构变化和地方政策因素是导致昌都地区土地利用结构熵值变化的直接动因,经济发展、人口增长等对土地系统熵值的时序变化也存在影响。信息熵理论反映某区域系统宏观尺度上的土地利用结构特征,对区域土地利用结构的调整有一定的指导和借鉴意义。该理论在区域土地利用结构分析中的应用研究有待进一步深入。     

燃煤电厂烟气氮氧化物排放控制技术发展现状

在广泛查阅文献的基础上,对近年来国内外已成功应用和正在研究开发的一些主要的燃煤烟气氮氧化物控制技术进行了介绍。结合我国目前脱硝行业整体水平和国家环保政策要求,对我国脱硝行业技术研发方向提出了建议。     

高压脉冲电凝-Fenton-生化法处理制药废水

通过高压脉冲电凝-Fenton对制药废水进行预处理,出水进入UASB-AO生化处理系统.研究表明:高压脉冲电凝-Fenton氧化法的最佳工况条件为进水pH值为4.0左右,高压脉冲电凝反应时间为45 min,H2O2投加量为4mL/L,Fenton氧化时间为60min.高压脉冲电凝-Fenton对CODCr去除率为36.5%～39.2%,ρ(BOD5)/ρ(CODCr)从0.13提高到0.32-0.34,废水的可生化性大大提高,UASB厌氧反应器去除率为81.4%～82.1%,AO系统去除率为88.0%～88.5%,而整个生化处理系统对CODCr去除率为95.4%～97.9%,最终出水各项指标可达到GB 8978-1996<污水综合排放标准>中一级标准.     

好氧颗粒污泥处理青霉素废水研究

青霉素在其生产过中产生大量的废水,其COD值较高,生化性较差,成分复杂,微生物难以降解,其处理技术是世界性难题。文章采用以葡萄糖模拟废水培养的好氧颗粒污泥为接种体,经青霉素废水逐步驯化后,使其完全处理青霉素废水。实验结果表明,应用好氧颗粒污泥技术,处理青霉素废水,COD,NH3_N,TP去除率较高,具有很好的处理效果。     

有机改性膨润土在印染废水处理中的应用

膨润土是一种非常有用的非金属矿物原料,其有机改性得到的有机改性膨润土可以较好地去除印染废水中的有机污染物和色度。本文综述了有机改性膨润土的制备方法及其在印染废水处理中的应用现状。     

Debromination of decabromodiphenyl ether by organo-montmorillonite-supported nanoscale zero-valent iron：Preparation, characterization and influence factors

An organo-montmorillonite-supported nanoscale zero-valent iron material(M-NZVI) was synthesized to degrade decabromodiphenyl ether(BDE-209). The results showed that nanoscale zero-valent iron had good dispersion on organo-montmorillonite and was present as a core-shell structure with a particle size range of nanoscale iron between 30–90 nm, characterized by XRD, SEM, TEM, XRF, ICP-AES, and XPS. The results of the degradation of BDE-209 by M-NZVI showed that the efficiency of M-NZVI in removing BDE-209 was much higher than that of NZVI. The efficiency of M-NZVI in removing BDE-209 decreased as the pH and the initial dissolved oxygen content of the reaction solution increased, but increased as the proportion of water in the reaction solution increased.     

Catalytic bubble-free hydrogenation reduction of azo dye by porous membranes loaded with palladium nanoparticles

Catalytic bubble-free hydrogenation reduction of azo dye by porous membranes loaded with palladium （Pd） nanoparticles was studied for the first time. The effects of Pd loading, dye concentration and reuse repetitions of membranes were investigated. In reduction, the dye concentration decreased whereas the pH rose gradually. An optimal Pd loading was found. The catalytic membranes were able to be reused more than 3 times.     

Carbonyl emissions from heavy-duty diesel vehicle exhaust in China and the contribution to ozone formation potential

Fifteen heavy-duty diesel vehicles were tested on chassis dynamometer by using typical heavy duty driving cycle and fuel economy cycle. The air from the exhaust was sampled by 2,4- dinitrophenyhydrazine cartridge and 23 carbonyl compounds were analyzed by high performance liquid chromatography. The average emission factor of carbonyls was 97.2 mg/km, higher than that of light-duty diesel vehicles and gasoline-powered vehicles. Formaldehyde, acetaldehyde, acetone and propionaidehyde were the species with the highest emission factors. Main influencing factors for carbonyl emissions were vehicle type, average speed and regulated emission standard, and the impact of vehicle loading was not evident in this study. National emission of carbonyls from diesel vehicles exhaust was calculated for China, 2011, based on both vehicle miles traveled and fuel consumption. Carbonyl emission of diesel vehicle was estimated to be 45.8 Gg, and was comparable to gasolinepowered vehicles （58.4 Gg）. The emissions of formaldehyde, acetaldehyde and acetone were 12.6, 6.9, 3.8 Gg, respectively. The ozone formation potential of carbonyls from diesel vehicles exhaust was 537 mg O3/km, higher than 497 mg O3/km of none-methane hydrocarbons emitted from diesel vehicles.