室内不同燃烧模式香烟污染的研究

香烟燃烧的主动吸烟、呼出烟雾、自由燃烧3种排放方式中,对一氧化碳CO、总挥发性有机物TVOC进行测定分析。自由燃烧模式较主动吸烟模式造成的CO和TVOC污染更高。对于室内环境的污染和被动吸烟者的危害,自由燃烧模式与呼出烟气模式的贡献比例CO和TVOC分别约为15/1和4/1。主动吸烟者吸入的烟气中CO和TVOC浓度可分别高达约10000mg/m3和800mg/m3,高出国家室内空气环境标准限量约1000倍,吸入的烟气中约有40%的CO通过肺部被人体吸收。     

“被动吸烟”的危害

“被动吸烟”的概念被动吸烟是指在一定的局部环境中,吸烟者人为造成的烟气污染局部空气,使不吸烟的个体或人群,在非志愿的情况下,被迫吸入烟草烟气。因此,它是主动吸烟的反义词。按照习惯的观念,总以为吸烟的危害主要是针对主动吸烟者的,但是现实生活告诉我们,实际的情况远非如此。在一些公共场所,例如:冬季火车车厢、地下商场及旅社、候车室、会议室、餐厅、饭馆、影剧院休息室、公共浴室休息室……,在通风换气不良的情况下,根据调查,烟草烟气对空气污染的严重程度,常常可超出通常大气污染的程度好多倍。很显然,环境保护的概念,并不仅仅是     

废物处理与综合利用

X7一’200lU2吕路沸石在环境保护中的新应用/朱建华…(南京大学化学化工学院)//安全与环境学报/北京理工大学一2(X)l,1(1)一3~7环图X一142 综述了沸石在控制环境中亚硝胺污染、净化处理废水以及沸石在农业生产和其他环境保护领域中应用的新进展。沸石是香烟添加剂的首选材料,能使测流烟气中的亚硝胺减少一半,主流烟气中减少约70%,减轻吸烟者和被动吸烟者的污染危害。沸石的净化作用源于其对亚硝胺特殊的催化和吸附作用,香烟燃烧所产生的亚硝胺如果在高温下接触沸石,将被催化裂解;如果亚硝胺在较低温度下接触沸石,也会被沸石吸附而不再污染…     

不同吊顶形式的地铁站台火灾人员疏散环境分析

以西安市某地铁车站岛式站台层为研究对象,利用火灾动力学模拟软件FDS,构建了3种不同吊顶形式(平板式、方形内凹式和格栅式)的站台层物理模型,在站台层5 MW火灾的情况下,对各个模型下烟气蔓延过程、吊顶层温度分布、人眼特征高度层温度分布、CO浓度分布和楼梯口处风速等与人员疏散环境相关参数进行了数值模拟,对比分析了3种不同吊顶形式下地铁车站站台层火灾的排烟效果。结果表明:方形内凹式吊顶可有效减缓烟气蔓延过程,降低楼梯口外侧烟气浓度,但会造成温度和CO浓度分布的局部波动;格栅式吊顶能提升烟气层高度,使人员疏散在火灾前中期处于更为安全的环境中,但烟气层过高不利于排烟口排烟。     

烟草加工与燃吸全过程的环境影响与危害分析

大量数据表明,烟草在生产加工过程中会产生和排放煤尘、烟草尘、恶臭气体、生产废水、烟草废弃物等各类污染和工业噪声,不仅对生产现场和周边环境造成污染,还会对作业工人造成呼吸道和听力损害及其他疾病危害。卷烟烟气中含有很多危及身体的毒性成分,吸烟场所空气中的尼古丁、颗粒物和有机物浓度均明显高于无烟和禁烟场所。吸烟是导致肺癌的首要危险因素,也是导致慢性阻塞性肺病的主要原因,更是多种癌症、心脑血管疾病等的重要诱因,被动吸烟的危害更为严重,全社会应正确引导烟草的生产和消费,最大可能地减轻烟草对人类造成的危害。     

带式输送机封闭通廊火灾特性研究

为研究带式输送机封闭通廊火灾烟气蔓延、温度及CO分布的影响因素,以某冶金企业厂区内一条运煤的封闭通廊作为研究对象,运用数值模拟方法,重点模拟了不同风速条件下封闭通廊内火灾烟气蔓延、温度和CO浓度的分布状况及其影响因素,并对封闭通廊侧壁开窗和设置喷淋系统后的温度分布进行了模拟分析。结果表明:纵向通风能抑制火灾烟气向封闭通廊内火源上游的蔓延,但加快了火灾烟气向封闭通廊内火源下游的扩散,同时有利于热量和CO的向外排出,延缓封闭通廊顶部达到钢结构临界温度所需的时间;封闭通廊侧壁设置窗户对高温火灾烟气向外扩散有积极的作用,但对火灾的抑制作用不如加装喷淋系统明显。     

北京市三类住宅室内CO、颗粒物污染及其元素分析

根据对三类有代表性住宅进行一年四季的有关监测及对户主所作个体碳氧血红蛋白(COHb)测定,研究表明室内空气污染较严重,尤其在冬季,颗粒物浓度普遍经常超标,CO更甚,可高达47ppm,室内空气污染与住房类型,特别是与取暖方式,关系密切,同类住宅当改用了中心供暖后,污染大为改善,30种元素分析表明是典型的燃煤夹杂风砂的污染,室内Pb浓度较高可能与使用液化石油气(LPG)灶具有关,吸烟的影响有时可被严重的室内污染所掩盖。     

吸烟对健康的影响

香烟烟雾中有上千种不同的化合物,其中包括焦油、多环烃,CO和NO_2。这些化合物都影响健康,已推导了致癌的相关性。据统计,吸烟者占肺癌死亡率的85％,慢性阻碍性肺病死亡率的70％,冠心病死亡率的30％,全部死亡率的15％。最近,研究了被动吸烟对健康的影响。被动吸烟者有吸入较小颗粒物和更多NO_2的趋势。这与肺癌和肺功能损害有关,但与心血管病无关。     

贵州农村地区冬季典型燃料产生的室内空气PM2.5和CO排放污染特征研究

贵州冬季阴冷潮湿,农村家庭使用原煤和生物质燃料作为家庭做饭和取暖燃料,室内空气污染对居民健康造成潜在危害。论文选取贵州农村地区冬季典型燃料使用产生的室内空气PM_2.5和CO排放为研究对象,研究其排放污染特征,并探讨室内空气CO-PM_2.5浓度间的相关性。研究结果表明,不同类型燃料的家庭室内PM_2.5浓度水平是燃煤 > 燃柴 > 沼气;厨房浓度高于客厅。燃煤的家庭厨房PM_2.5浓度最高,为222.54±41.12 μg/m³,燃柴家庭次之,为130.48±26.53 μg/m³,燃沼气家庭的厨房为74.95±19.20 μg/m³。室内CO浓度较低,不同类型燃料的家庭室内CO浓度水平是燃柴 > 燃煤 > 沼气。燃柴家庭客厅CO浓度最高,为3.16±0.73 mg/m³,其次是燃柴家庭的厨房,为2.76±0.25 mg/m³;燃煤家庭的厨房CO浓度较低,为2.32±0.33 mg/m³;最低为燃沼气家庭的厨房,为0.66±0.07 mg/m³。除沼气村外,燃煤及燃柴家庭室内(厨房和客厅)PM_2.5浓度均超过环境空气质量标准(GB3095-2012)PM_2.5限值75 μg/m³,室内CO浓度均低于该标准中CO限值10 mg/m³。固体燃料燃烧是贵州农村PM_2.5的主要来源,室内PM_2.5和CO浓度相关性分析表明二者不具有显著相关性,采用CO监测值来推算PM_2.5以提高监测效率的应用可能性受到限制。研究表明,贵州农村地区需采取更加有效的干预措施以减少室内空气污染尤其是控制PM_2.5排放。     

南京青奥会期间不同天气型气溶胶数浓度分布特征

该文利用WPS、β射线测尘仪、EMS污染气体监测系统的观测数据,结合观测期间天气形势,分析了青奥会期间南京不同天气型下气溶胶数浓度和污染气体的分布特征。结果表明:观测期间气溶胶数浓度平均为7 302个/cm~3,污染气体(NOx、O_3、SO_2、CO)平均浓度分别为23.09、55.1、8.7和867.3μg/m~3。不同天气型下气溶胶粒径分布差异较大,鞍型场(Ⅱ)、副热带高压(Ⅴ)和冷涡(Ⅲ)控制下数浓度谱呈单峰型分布;大陆高压和热带气旋外围(Ⅰ)控制下数浓度谱呈双峰型分布;冷高压(Ⅳ)控制下数浓度谱呈三峰型分布。同时日浓度变化差异也大,N_(10~300 nm)在Ⅰ型、Ⅲ型、Ⅳ型呈三峰型,在Ⅱ型、Ⅴ型呈双峰型;NOx和CO在Ⅰ型分别呈三峰型和单峰型,其余都是双峰型;O_3一直呈单峰型。     

Toxic effects of acetochlor, methamidophos and their combination on nifH gene in soil

Toxic effects of two agrochemicals on nifH gene in agricultural black soil were investigated using denaturing gradient gel electrophoresis （DGGE） and sequencing approaches in a microcosm experiment. Changes of soil nifH gene diversity and composition were examined following the application of acetochlor, methamidophos and their combination. Acetochlor reduced the nifH gene diversity （both in gene richness and diversity index values） and caused changes in the nifH gene composition. The effects of acetochlor on nifH gene were strengthened as the concentration of acetochlor increased. Cluster analysis of DGGE banding patterns showed that nifH gene composition which had been affected by low concentration of acetochlor （50 mg/kg） recovered firstly. Methamidophos reduced nifH gene richness that except at 4 weeks. The medium concentration of methamidophos （150 mg/kg） caused the most apparent changes in nifH gene diversity at the first week while the high concentration of methamidophos （250 mg/kg） produced prominent effects on nifH gene diversity in the following weeks. Cluster analysis showed that minimal changes of nifH gene composition were found at 1 week and maximal changes at 4 weeks. Toxic effects of acetochlor and methamidophos combination on nifH gene were also apparent. Different nifH genes （bands） responded differently to the impact of agrochemicals： four individual bands were eliminated by the application of the agrochemicals, five bands became predominant by the stimulation of the agrochemicals, and four bands showed strong resistance to the influence of the agrochemicals. Fifteen prominent bands were partially sequenced, yielding 15 different nifH sequences, which were used for phylogenetic reconstructions. All sequences were affiliated with the alpha- and beta-proteobacteria, showing higher similarity to eight different diazotrophic genera.     

Arsenic uptake by arbuscular mycorrhizal maize （Zea mays L.） grown in an arsenic-contaminated soil with added phosphorus

The effects of arbuscular mycorrhizal (AM) fungus (Glomus mosseae) and phosphorus (P) addition (100 mg/kg soil) on arsenic (As) uptake by maize plants (Zea mays L.) from an As-contaminated soil were examined in a glasshouse experiment.Non-mycorrhizal and zero-P addition controls were included.Plant biomass and concentrations and uptake of As,P,and other nutrients,AM colonization,root lengths,and hyphal length densities were determined.The results indicated that addition of P significantly inhibited root colonization and development of extraradical mycelium.Root length and dry weight both increased markedly with mycorrhizal colonization under the zero-P treatments,but shoot and root biomass of AM plants was depressed by P application.AM fungal inoculation decreased shoot As concentrations when no P was added,and shoot and root As concentrations of AM plants increased 2.6 and 1.4 times with P addition,respectively.Shoot and root uptake of P,Mn,Cu,and Zn increased,but shoot Fe uptake decreased by 44.6%,with inoculation, when P was added.P addition reduced shoot P,Fe,Mn,Cu,and Zn uptake of AM plants,but increased root Fe and Mn uptake of the nonmycorrhizal ones.AM colonization therefore appeared to enhance plant tolerance to As in low P soil,and have some potential for the phytostabilization of As-contaminated soil,however,P application may introduce additional environmental risk by increasing soil As mobility.     

Degradation of metabolites accumulated of benzo[a]pyrene by coupling Penicillium Chrysogenum with KMnO4

Several main metabolites of benzo[a]pyrene （BaP） formed by Penicillium chrysogenum, Benzo[a]pyrene-1,6-quinone （BP 1,6- quinone）, trans-7,8-dihydroxy-7,8-dihydrobenzo[a]pyrene （BP 7,8-diol）, 3-hydroxybenzo[a]pyrene （3-OHBP）, were identified by high-performance liquid chromatography （HPLC）. The three metabolites were liable to be accumulated and were hardly further metabolized because of their toxicity to microorganisms. However, their further degradation was essential for the complete degradation of BaP. To enhance their degradation, two methods, degradation by coupling Penicillium chrysogenum with KMnO4 and degradation only by Penicillium chrysogenum, were compared; Meanwhile, the parameters of degradation in the superior method were optimized. The results showed that （1） the method of coupling Penicillium chrysogenum with KMnO4 was better and was the first method to be used in the degradation of BaP and its metabolites; （2） the metabolite, BP 1,6-quinone was the most liable to be accumulated in pure cultures; （3） the effect of degradation was the best when the concentration of KMnO4 in the cultures was 0.01% （w/v）, concentration of the three compounds was 5 mg/L and pH was 6.2. Based on the experimental results, a novel concept with regard to the bioremediation of BaP-contaminated environment was discussed, considering the influence on environmental toxicity of the accumulated metabolites.     

Impact of atrazine and nitrogen fertilizers on the sorption of chlorotoluron in soil and model sorbents

Sorption of chlorotoluron in ammonium sulfate, urea and atrazine multi-solutes system was investigated by batch experiments. The results showed application of nitrogen fertilizers to the soil could affect the behavior of chlorotoluron. At the same concentration of N, sorption of chlorotoluron decreased as the concentration of atrazine increased on the day 0 and 6 in soil, respectively. The sorption of chlorotoluron increased from 0 to 6 d when soils were preincubated with deionized water, ammonium sulfate and urea solution for 6 d. That indicated incubation time was one of the most important factors for the sorption of chlorotoluron in nitrogen fertilizers treatments. The individual sorption isotherms of chlorotoluron in rubbery polymer and silica were strictly linear in single solute system, but there were competition sorption between pesticides or between pesticides and nitrogen fertilizers. That indicated the sorption taken place by concurrent solid-phase dissolution mechanism and sorption on the interface of water-organic matter or water-mineral matter.     

Potential of plant polyphenol oxidases in the decolorization and removal of textile and non-textile dyes

In this study an effort has been made to use plant polyphenol oxidases; potato （Solanum tuberosum） and brinjal （Solanum melongena）, for the treatment of various important dyes used in textile and other industries. The ammonium sulphate fractionated enzyme preparations were used to treat a number of dyes under various experimental conditions. Majority of the treated dyes were maximally decolorized at pH 3.0. Some of the dyes were quickly decolorized whereas others were marginally decolorized. The initial first hour was sufficient for the maximum decolorization of dyes. The rate of decolorization was quite slow on long treatment of dyes. Enhancement in the dye decolorization was noticed on increasing the concentration of enzymes. The complex mixtures of dyes were treated with both preparations of polyphenol oxidases in the buffers of varying pH values. Potato polyphenol oxidase was significantly more effective in decolorizing the dyes to higher extent as compared to the enzyme obtained from brinjal polyphenol oxidase. Decolorization of dyes and their mixtures, followed by the formation of an insoluble precipitate, which could be easily removed simply by centrifugation.     

Effects of two sludge application on fractionation and phytotoxicity of zinc and copper in the soil

The potential harm of heavy metals is a primary concern in application of sludge to the agricultural land. A pot experiment was conducted to evaluate the effect of two sludges on fractionation of Zn and Cu in soil and their phytotoxicity to pakchoi. The loamy soil was mixed with 0%, 20%, 40%, 60% and 80% (by weight) of digested sewage sludge (SS) and composted sludge (SC). The additions of both sludges caused a significant raise in all fractions, resulting in that exchangeable (EXCH) and organic bound (OM) became predominance of Zn and organic bound Cu occupied the largest portion. There was more available amount of Zn and Cu in SS treatments than SC treatments. During the pot experiment, the concentration of Zn in EXCH, carbonate (CAR) and OM and Cu in EXCH and OM fractions decreased in all treatments, so their bioavailability reduced. Germination rate and plant biomass decreased when the addition rate was high and the best yield appeared in 20% mixtures at the harvest of pakchoi. The two sludges increased tissue contents of Zn and Cu especially in the SS treatments. Zn in pakchoi was not only in relationship to ΔEXCH and ΔCAR forms but also in ΔOM forms in the sludge-soil mixtures. Tissue content of Cu in pakchoi grown on SC-soils could not be predicted by ΔEXCH. These correlation rates between Zn and Cu accumulation in pakchoi and variation of different fractions increased with time, which might indicate that sludges represented stronger impacts on the plant in long-term land application.     

Intraspecific differences in effects of co-contamination of cadmium and

A hydroponic experiment was carried out to study intraspecific differences in the effects of different concentrations of cadmium (Cd)(0-10 mg/L) and arsenate (As(V)) (0-8 mg/L) on the growth parameters and accumulation of Cd and As in six wheat varieties Jing-9428, Duokang-1, Jingdong-11, Jing-411, Jingdong-8 and Zhongmai-8. The endpoints of wheat seedlings, including seed germination,biomass, root length and shoot height, decreased with increasing the Cd and As concentrations. Significant differences in seed germination, biomass, root length, shoot height and the accumulation of Cd and As were observed between the treatments and among the varieties (p ＜ 0.05). The lethal dosage 50% were about 20, 80, 60, 60, 80 and 20 mg As/L for Jing-9428, Duokang-1, Jingdong-11,Jing-411, Jingdong-8 and Zhongmai-8, respectively, and the corresponding values for Cd were about 30, 80, 20, 40, 60 and 10 mg Cd/L, respectively. Among the six varieties, Duokang-1 was found to be the most resistant to Cd and As toxicity, and Zhongmai-8 was the most sensitive to Cd and As co-contamination. The resistance of the six varieties was found dependant on the seedling uptake of Cd and As. Duokang-1 was the most suitable for cultivation in Cd and As co-contaminated soils.     

Removal of heavy metals from sewage sludge by low costing chemical method and recycling in agriculture

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Single and joint effects of pesticides and mercury on soil urease

The influence of two pesticides including chlorimuron-ethyl and furadan and mercury （Hg） on urease activity in 4 soils （meadow burozem and phaeozem） was investigated. The soils were exposed to various concentrations of the two pesticides and Hg individually and simultaneously. Results showed that there was a close relationship between urease activity and organic matter content in soil. Chlorimuron-ethyl and furadan could both activate urease in the 4 soils. The maximum increment of urease activity by chlorimuronethyl was up to 14%-18%. There was almost an equal increase （up to 13%-21%） in the urease activity by furadan. On the contrary, Hg markedly inhibited soil urease activity. A logarithmic equation was used to describe the relationship （P〈0.05） between the concentration of Hg and the activity of soil urease in the 4 tested soils. Semi-effect dose （ED50） values by the stress of Hg based on the inhibition of soil urease in the 4 soils were 88, 5.5, 24 and 20 mg/kg, respectively, according to the calculation of the corresponding equations. The interactive effect of chlorimuron-ethyl or furadan with metal Hg on soil urease was mainly synergic at the highest tested concentrations.     

Isolation and preliminary characterization of a 3-chlorobenzoate degrading bacteria

A study was conducted to compare the diversity of 2-, 3-, and 4-chlorobenzoate degraders in two pristine soils and one contaminated sewage sludge. These samples contained strikingly different populations of mono-chlorobenzoate degraders. Although fewer cultures were isolated in the uncontaminated soils than contaminated one, the ability of microbial populations to mineralize chlorobenzoate was widespread. The 3- and 4-chlorobenzoate degraders were more diverse than the 2-chlorobenzoate degraders. One of the strains isolated from the sewage sludge was obtained. Based on its phenotype, chemotaxonomic properties and 16S rRNA gene, the organism S-7 was classified as Rhodococcus erythropolis. The strain can grow at temperature from 4 to 37℃. It can utilize several （halo）aromatic compounds. Moreover, strain S-7 can grow and use 3-chlorobenzoate as sole carbon source in a temperatures range of 10-30℃ with stoichiometric release of chloride ions. The psychrotolerant ability was significant for bioremediation in low temperature regions. Catechol and chlorocatechol 1,2-dioxygenase activities were present in cell free extracts of the strain, but no （chloro）catechol 2,3- dioxygenase activities was detected. Spectral conversion assays with extracts from R. erythropolis S-7 showed accumulation of a compound with a similar UV spectrum as chloro-cis,cis-muconate from 3-chlorobenzoate. On the basis of these results, we proposed that S-7 degraded 3-chlorobenzoate through the modified ortho-cleave pathway.