Simultaneous monitoring of profiles of polycyclic aromatic hydrocarbons in contaminated air with semipermeable membrane devices and spruce needles

Gaseous emissions of combusted electronic scrap, PVC, carpet and wood were monitored for polycyclic aromatic hydrocarbons (PAHs) by simultaneous use of semipermeable membrane devices (SPMDs) and shoots of spruce needles (Picea abies). It was found that phenanthrene, acenaphthylene and fluorene were the dominating PAHs in all samples. SPMDs and needles mainly sequestered PAH associated with the vapor phase. Particle-bound PAHs were only detected in small amounts, at which the needles tended to uptake more of these compounds in comparison to the SPMDs. Nevertheless, the logarithm of the concentrations of PAHs analyzed in both passive samplers after the same sampling period exhibited a significant linear correlation with correlation coefficients larger than 0.8073. SPMDs and spruce needles can complement each other in passive air sampling for compounds with a preference to the gas phase rather than aerosols.     

Concentrations and inhalation risk assessment of short-chain polychlorinated paraffins in the urban air of Dalian,China

Environmental Science and Pollution Research - The concentrations of short-chain polychlorinated paraffins (SCCPs) in the urban air of Dalian, China, were monitored from March to October 2010 and...     

缺氧—好氧—催化臭氧氧化工艺处理石化厂含盐废水

采用缺氧—好氧—催化臭氧氧化工艺处理某石化厂的含盐废水。实验结果表明：在进水COD为200~350 mg/L的条件下,经生化处理后的出水COD稳定在50~60 mg/L,COD去除率稳定在75%左右;在臭氧投加量为4.5 g/L、V（催化剂Ⅱ）∶V（废水）=1.5∶1的条件下,进行连续催化臭氧氧化后出水COD稳定在20 mg/L以下,COD去除率大于70%,满足DB 61/224—2011《黄河流域（陕西段）污水综合排放标准》。表征结果显示,催化剂表面含有铜元素,比表面积为250.815 m²/g,吸水率为60.9%,经过滤可去除废水中残留的催化剂。     

生活垃圾中废旧塑料的二次分选技术

由于城市垃圾中塑料品种繁杂、质量差,回收利用十分困难,国内外对于垃圾中的废旧塑料回收利用甚少。通过技术比选,确定采用多种分选技术的优势组合,以风力分选-X射线分选-光电分选相结合的组合工艺技术,实现对主要塑料品种PO,PS,PVC,PET等的有效分离,以加大废旧塑料的回收利用,减少环境污染,提高资源利用效率。     

二级膜分离—冷凝—吸附工艺处理石化罐区废气

采用二级膜分离—冷凝—变压吸附工艺回收处理含有高浓度挥发性有机物和苯系物的炼厂罐区外排“呼吸气”。结果表明,进气的非甲烷总烃质量浓度范围41 000~182 000 mg/m³,进气中苯、甲苯和二甲苯的质量浓度分别为400~1 400 mg/m³,150~1 600 mg/m³,300~2 100 mg/m³时,尾气中非甲烷总烃质量浓度始终低于80 mg/m³,去除率均高于99.9%,苯、甲苯和二甲苯的去除率分别为99.6%、99.6%和99.8%。抗冲击负荷实验将进气量提高50%,尾气中非甲烷总烃质量浓度仍低于80 mg/m³。二级膜单元可以高效浓缩轻烃,既回收获得可燃气,又解决了轻烃积累所造成的尾气超标难题。     

生物滴滤塔处理含H_2S和NH_3气体的中试研究

利用生物滴滤塔对含H_2S和NH_3气体的处理进行了中试研究.经培养驯化的活性污泥在生物滴滤塔上挂膜后,对H_2S和NH_3的去除率分别达85%和90%以上,处理后NH_3出口质量浓度小于0.2 mg/m~3、H_2S出口质量浓度小于0.001 mg/m~3,均达到GB14554-93<恶臭污染物排放标准>和TJ36-79<工业企业设计卫生标准>.对装置连续运行的稳定性研究表明,NH_3和H_2S的去除率均能保持稳定.     

生物邻体和生境异质性共同驱动乔木幼苗存活动态

以长白山原始阔叶红松林样地为平台,样方中胸径小于1 cm的乔木幼苗为研究对象,基于2012-2014年连续3年的幼苗调查数据,利用广义线性混合模型分析影响群落乔木幼苗存活的生物邻体和生境异质性,探讨阔叶红松林幼苗存活影响因素及物种共存机制.结果显示:(1)生物邻体和生境异质性对幼苗存活都有显著影响,适宜大树生长的局域生境可能同样也适宜幼苗的存活,幼苗在林冠开阔度较高和土壤中含有较高有效氮、全磷和全钾的区域存活率较高.(2)幼苗个体之间存在明显的竞争,较多的幼苗邻体会显著降低幼苗的存活率.2年生幼苗存活分析中同种幼苗邻体与幼苗存活呈显著负相关,表明存在负密度制约效应.(3)随着存活年龄的增加,生境异质性对幼苗存活的影响逐渐增大.本研究验证了负密度制约效应和生境异质性对该温带森林乔木幼苗存活有着重要影响,各个因子的相对重要性随着种子传播方式、年龄级以及物种而发生变化,证明群落多样性维持和物种共存会随着个体发育过程的不同而变化.     

灾害教育理论研究与实践的初步思考

防灾减灾是可持续发展战略的重大课题,防灾减灾目标的实现在很大程度上依靠灾害教育。在国际灾害教育图景下,结合我国自然灾害多发的地理国情与公民防灾素养不高的实际情况,思考如何进行灾害教育研究与实践,从基本概念入手,提出研究思路,进行国际比较梳理其发展历程,分析灾害教育研究现状与存在问题,提出构建我国灾害教育体系的策略与设想,以促进其发展,确保人民群众生命财产安全。     

Photocatalytic degradation of C. I. Reactive Red 24 solution with K6SiW11O39SnⅡ

Environmental friendly materials, K₆SiW₁₁O₃₉Sn (SiWSn), was synthesized. SiWSn photocatalytic decomposition of C. I. Reactive Red 24 (RR24) with the UV-lamp (253.7 nm, 20 W), Xenon lamp filtered less than 390 nm light (500 W) and sun light was investigated. The results showed that RR24 solution could be effectively decolorized with the SiWSn photocatalyst. The photocatalytic degradation efficiency of RR24 with SiWSn was affected by the initial concentration of RR2 solution, the amount of SiWSn and the photolysis time. It is demonstrated that the process of photodegradation of RR24 with SiWSn is a pesudo first-order reaction, which can be described by Langmuir-Hinshelwood equation. Hydroxyl radicals and holes are both the main oxidants in the photocatalytic reaction of RR24 with SiWSn.     

水体中悬浮颗粒物对总磷自动监测仪测试的影响

为保障自动监测数据的准确性,提升水质自动监测系统中水样前处理效果,对几种常用的预处理方式进行比较,分析了低浊度时预处理方式及颗粒物成分对总磷测试的影响,对比不同预处理方式对监测数值的影响、总磷自动监测仪测试数据与实验室监测测试数据的差异,减少水体中悬浮颗粒物对总磷自动监测仪测试的影响.