相对湿度对大气中半挥发性有机物气态／粒子态组成比例的影响

在大气环境中，化合物的气态／粒子态组成比例系数ＫＰ＝（Ｆ／ＴＳＲ）／Ａ，式中Ｆ（ｎｇ／Ｍ＾３）是化合物的粒子缔合浓度，Ａ（ｎｇ／Ｍ＾３）是化合物的气态浓度，ＴＳＰ（μｇ／Ｍ＾３）是总悬浮微粒的浓度。ＫＰ是温度（Ｔ，Ｋ）的函数，其表达式为ｌｏｇＫＰ＝ｍｐ／Ｔ＋ｂｐ，利用日本大孤城区的数据，在相对湿度对ＫＰ值的影响，由此确定出比例系的测定值（ｌｏｇＫＰ）与计算值（ｍｐ／Ｔ＋ｂｐ）之间的残差为ｃｐＲＨ＋     

有机气溶胶的来源与形成研究现状

介绍了有机气溶胶来源与形成的研究现状,从有机气溶胶的化学组成特征、一次有机气溶胶的来源和二次有机气溶胶的形成机制论述其研究进展.一次有机气溶胶主要来源于烹调油烟、机动车排放、生物质燃烧、工业或民用燃油锅炉释放出的有机物,还有道路扬尘、沥青、刹车尘、轮胎屑、室外香烟烟雾、以及高等植物蜡、细菌活动和草本植物等.大气中的半挥发性有机物可通过物理和化学吸附形成二次有机气溶胶,一些挥发性有机物可通过气相化学反应转化为低挥发性的物质并形成二次有机气溶胶,其主要前体物是芳香族化合物,如苯、甲苯、二甲苯,以及烯烃、烷烃、环烷烃、萜烯和生物排放的非饱和氧化物.     

Biogenic VOCs emission inventory development of temperate grassland vegetation in Xilin River basin, Inner Mongolia, China

Given the key role of biogenic volatile organic compounds(VOCs) to tropospheric chemistry and regional air quality, it is important to generate accurateVOCs emission inventories. However, only a less fraction of plant species, in temperate grassland of Inner Mongolia, has been characterized by quantitative measurements. A taxonomic methodology, which assigns VOCs measurements to unmeasured species, is an applicable and inexpensive alternation for extensive VOCs emission survey, although data are needed for additional plant families and genera to further validate the taxonomic approach in grassland vegetation. In this experiment, VOCs emission rates of 178 plant species were measured with a portable photoionization detector( PID). The results showed the most of genera and some families have consistent feature of their VOCs emission, especially for isoprene, and provide the basic premise of taxonomic methodology to develop VOCs emission inventories for temperate grassland. Then, the taxonomic methodology was introduced into assigning emission rate to other 96 species, which no measured emission rates available here. A systematical emission inventory of temperate grassland vegetation in Inner Mongolia was provided and further evidence that taxonomy relationship can serve as a useful guide for generalizing the emissions behavior of many, but not all, plant families and genera to grassland vegetation.     

废气生物控制技术

本文着重综述废气的生物处理技术,介绍其特性、优缺点和应用范围。挥发性有机和无机物及臭味,可在生物滤池、生物洗涤器和生物滴滤池中,经吸收或吸附和生物分解而有效地去除。其应用范围可扩大到较高浓度和流量,并可扩大可降解化合物的范围,生物技术的最新发展,可使疏水性挥发物的处理更有效。因此,生物控制技术越来越受人们重视,将在大气污染防治中起重要作用。     

阳极溶出伏安法连续测定底泥中的总镉和总铅

底泥样品经盐酸-硝酸-氢氟酸-高氯酸消解后,用1 1盐政溶解残渣,以高氯酸做支持电解质,采用阳极溶出伏安法的标准加入法,连续测定样品中的总镉和总铅.该方法测定土壤标准样品中镉和铅的相对标准偏差分别为5.6%和4.6%,相对误差分别为2.4%和～1.7%;测定自采底泥样品中镉和铅的相对偏差分别为7.7%和8.1%,方法的重复性好;测定土壤标准样品中镉加标回收率为94.0%～106.8%,铅加标回收率为95%～103.8%;自采样品中镉加标回收率为93.0%～105.6%,铅加标回收率为90.0%～105.0%,方法的准确度较高.实验中,镉和铅的半波电位稳定,峰形对称.     

Catalytic dechlorinafion of o-chlorophenol by nanoscale Pd／Fe

Transformation of chlorophenols by nanoscale bimetallic particles represents one of the latest innovative technologies for environmental remediation. Nanoscale Pd/Fe bimetallic particles were synthesized in the laboratory for treatment of o-chlorophenol. Most of the nanoscale particles are in the size range of 20-100 nm. BET specific surface area of the nanoscale Pd/Fe particles is 12.4 m2/g. In comparison, a commercially available Fe powder( < 100 mesh) has a specific surface area of just 0.49 m2/g. Batch experiments demonstrated that the nanoscale Pd/Fe bimetallic particles can effectively dechlorinate o-chlorophenol. Dechlorination efficiency is affected by the mass fraction of Pd in the bimetal, nanoscale Pd/Fe mass concentration and mixing intensity.     

水解酸化-好氧工艺处理感光材料有机废水研究

感光材料有机生产废水含有多种合成有机物，其BOD5／CODer比值为0．46～0．48，可生化性良好，经水解酸化处理后该废水的BOD5／CODcr的比值可提高至0．54～056，平均增加了17％左右。水解酸化－好氧串联工艺对该废水总的处理效果表明：在废水CODer进水浓度2000～2500mg／L范围内，CODer总去除率可达95％左右，BOD5总去除率可达97％左右；水解酸化后好氧生化系统的动力学半速度常数Ks＝103mg／L，最大比降解速度K＝5．0／日。     

室内空气中挥发性有机物污染研究进展

分析了国内外在室内空气中挥发性有机物污染方面的研究结果，提出我国应该重视这一领域研究的建议和今后的工作设想。