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661.
Since volatile mold metabolites are used for the detection of mold growth in buildings, it was interesting to determine whether different indoor mold species show different affinity for the major components of wood, a common building material. Growth and volatile metabolites were studied when Aspergillus versicolor, Penicillium chrysogenum, and P. palitans were grown on laboratory substrates containing the major wood constituents cellulose, xylan and lignin. Microbial volatile organic compounds (MVOCs) were characterized by thermal desorption/gas chromatography/mass spectroscopy. Growth and volatile metabolites varied considerably and there appeared to be complementary substrate specificities for P. chrysogenum, and P. palitans grown on cellulose and xylan. The failure of A. versicolor to produce characteristic MVOCs when grown on media containing wood constituents suggests that systems using volatile metabolites to detect microbial growth in buildings may be fundamentally unreliable for the detection of this species.  相似文献   
662.
生态农业园区废弃物资源化处理利用研究   总被引:2,自引:0,他引:2  
本文介绍了蟹岛生态园区农业废气物及生活污水的资源化处理工艺方案 ,通过对沼气池和生活污水厌氧 -好氧 -生态塘处理系统进行综合设计 ,实现了节能环保和废弃物无害化综合处理利用。形成了种植业、养殖业、肥料加工、能源利用和休闲度假有机结合的生态农业经济 ,为实现农村经济可持续发展提供了一种新模式  相似文献   
663.
本文研究SBR工艺处理汽车电泳废水在不同有机负荷、溶解氧条件下污泥膨胀的现象 ,分析膨胀发生机理 ,分别提出控制方法。实验结果表明 ,在低、中、高负荷时 ,只要溶解氧发生变化 ,均有可能发生膨胀。低负荷、正常溶解氧时发生的膨胀可以通过前联好氧生物选择器加以控制 ;中负荷、低溶解氧及高负荷、低溶解氧活性污泥发生膨胀时可以通过强化曝气得到控制  相似文献   
664.
采用热脱附-气相色谱/质谱联用法对4辆处于静止状态下的车辆内部空气中挥发性有机物(VOCs)进行了研究,共定性检出了48种有机物,其中C6~C9之间的组分较多;并对VOCs的总浓度进行了定量,1#~4#车分别为1846、2289、1104和3146 μg/m^3;其中BTEX占VOCs总量的20%~30%;车内VOCs浓度与温度及车辆使用年限密切相关.  相似文献   
665.
新装饰装修房屋室内空气中的苯系物调查   总被引:1,自引:0,他引:1  
对新装饰装修房屋室内的一类主要有机苯系污染物进行了调查,调查采用吸附柱采集、GC/MS 和GC-FID测定,检测了321家居室内的苯系物.检出的苯系物有12种,苯平均浓度为0.068 mg/m^3,有86.9%的居室符合《室内空气质量标准》(GB/T18883-2002)规定的限量值,甲苯、二甲苯平均浓度分别为0.14 mg/m^3和0.41 mg/m^3,符合《室内空气质量标准》规定限值的居室分别达85.4%和73.3%.苯系物约占室内空气中TVOC的62%,浓度由低到高分别是苯、甲苯、乙苯和二甲苯,其中二甲苯中的间二甲苯占二甲苯总量的55% .  相似文献   
666.
Mathematical models were developed to investigate the characteristics of gaseous ozone transport under various soil conditions and the feasibility of in situ ozone venting for the remediation of unsaturated soils contaminated with phenanthrene. On the basis of assumptions for the mass transfer and reactions of ozone, three approaches were considered: equilibrium, kinetic, and lump models. Water-saturation-dependent reactions of gaseous ozone with soil organic matter (SOM) and phenanthrene were employed. The models were solved numerically by using the finite-difference method, and the model parameters were determined by using the experimental data of Hsu [The use of gaseous ozone to remediate the organic contaminants in the unsaturated soils, PhD Thesis, Michigan State Univ., East Lansing, MI, 1995]. The transport of gas-phase ozone is significantly retarded by ozone consumption due to reactions with SOM and phenanthrene, in addition to dissolution. An operation time of 156 h was required to completely remove phenanthrene in a 5-m natural soil column. In actual situations, however, the operation time is likely to be longer than the ideal time because of unknown factors including heterogeneity of the porous medium and the distribution of SOM and contaminant. The ozone transport front length was found to be very limited (< 1 m). The sensitivity analysis indicated that SOM is the single most important factor affecting in situ ozonation for the remediation of unsaturated soil contaminated with phenanthrene. Models were found to be insensitive to the reaction mechanisms of phenathrene with either gas-phase ozone or dissolved ozone. More study is required to quantify the effect of OH* formation on the removal of contaminant and on ozone transport in the subsurface.  相似文献   
667.
介绍了工厂有机溶剂废气处理方案和设计及实际运行效果,具有简单经济、净化彻底的特点.  相似文献   
668.
Phthalate esters are used as plasticizer in many plastics, and several studies have shown their toxicity. Phthalate esters are gradually emitted over time, and so it is conceivable that they pose a significant health risk. This study aims to investigate the temperature dependence of the emissions of various phthalate esters and to estimate the health risks of these emissions at various temperatures. A passive-type sampler was developed to measure the flux of phthalate esters from the surface of plastic materials. With this sampler, we examined three widely used plastic materials: synthetic leather, wallpaper and vinyl flooring. The observed maximum emissions of diethyl phthalate, dibutyl phthalate, and diethylhexyl phthalate (DEHP) from these materials at 20°C were 0.89, 0.77, and 14 μg m−2 h−1, respectively. Emissions at 80°C were 2.8, 4.5×102, and 1.5×103 μg m−2 h−1, respectively. The results showed this temperature dependence is determined primarily by the type of phthalate ester and less so by the type of material. The estimation from the results of temperature dependence indicated the concentration of DEHP in a vehicle left out in the sunshine during the day can exceed the recommended levels of Japan Ministry of Health, Labour and Welfare.  相似文献   
669.
有机物的结构──活性定量关系及其在环境化学和环境毒理学中的应用王飞越(北京大学城市与环境学系,北京100871)陈雁飞(武汉大学环境科学系)最近几十年来,有机物结构──活性定量关系研究(QSAR,QuantitativeStructure-Activ...  相似文献   
670.
以深圳市某污水处理厂的污泥为原料,研究了污泥热解过程产生的颗粒物及其中8种重金属的分布规律.结果表明,颗粒物的生成速率分别在400~600℃和1000℃保温30min的两个区间内达到峰值.8种重金属的热挥发性由大到小依次为Cd > Zn > As > Pb > Mn > Ni > Cu > Cr,而其在颗粒物中富集能力大小顺序为Pb > As > Mn > Zn > Cd > Ni > Cr > Cu.颗粒物重金属在热解气中的体积浓度随热解过程呈上升趋势,Zn和Cd则在升温阶段(1000℃以前)达到峰值后开始降低.研究表明,污泥热解颗粒物富集的重金属超标,因而污泥热解尾气颗粒物的去除装置十分必要.  相似文献   
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