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971.
Air pollution surveys of formaldehyde(HCHO) were conducted in 2324 rooms decorated within one year in 2007-2009 in Hangzhou,China.The mean HCHO concentration(C HCHO) was 0.107 ± 0.095 mg/m 3,and 38.9% of samples exceeded the Chinese National Standard GB 50325-2010.Over the past 3 years,the C HCHO decreased with time(p < 0.05).Relationships of potential factors to indoor C HCHO were also evaluated.C HCHO was related to temperature(T),relative humidity(RH),time duration of the windows and doors being closed before sampling(DC),time duration from the end of decoration to sampling(DR) and source characteristics(d).A model to relate indoor C HCHO to these five factors(T,RH,DC,DR,d) was established based on 298 samples(R 2 = 0.87).Various factors contributed to C HCHO in the following order:T,43.7%;d,31.0%;DC,10.2%;DR,8.0%;RH,7.0%;specifically,meteorological conditions(i.e.,RH plus T) accounted for 50.7%.The coefficient of T and RH,R TH,was proposed to describe their combined influence on HCHO emission,which also had a linear relationship(R 2 = 0.9387) with HCHO release in a simulation chamber test.In addition,experiments confirm that it is a synergistic action as T and RH accelerate the release of HCHO,and that is a significant factor influencing indoor HCHO pollution.These achievements could lead to reference values of measures for the efficient reduction of indoor HCHO pollution.  相似文献   
972.
The uncertainty in emission estimation is strongly associated with the variation in emission factor (EF),which could be influenced by a variety of factors such as fuel properties,stove type,fire management and even methods used in measurements.The impacts of these factors are complicated and often interact with each other.Controlled burning experiments were conducted to investigate the influences of fuel mass load,air supply and burning rate on the emissions and size distributions of carbonaceous particulate matter (PM) from indoor corn straw burning in a cooking stove.The results showed that the EFs of PM (EFPM),organic carbon (EFOC) and elemental carbon (EFEC) were independent of the fuel mass load.The differences among them under different burning rates or air supply amounts were also found to be insignificant (p > 0.05) in the tested circumstances.PM from the indoor corn straw burning was dominated by fine PM with diameter less than 2.1 μm,contributing 86.4%±3.9% of the total.The size distribution of PM was influenced by the burning rate and air supply conditions.On average,EF PM,EF OC and EF EC for corn straw burned in a residential cooking stove were (3.84±1.02),(0.846±0.895) and (0.391±0.350) g/kg,respectively.EF PM,EF OC and EF EC were found to be positively correlated with each other (p < 0.05),but they were not significantly correlated with the EF of co-emitted CO,suggesting that special attention should be paid to the use of CO as a surrogate for other incomplete combustion pollutants.  相似文献   
973.
结合工程实例,介绍了大孔树脂吸附预处理及耐盐菌水解酸化-接触氧化工艺在处理含酚、高含盐农药废水处理工程中的实际应用。运行结果表明,该工艺可回收废水中大部分酚类,能够耐受较高的含盐量,运行稳定,处理效果好,各项出水指标均能达GB 8978—1996《污水综合排放标准》三级排放标准。  相似文献   
974.
Environmental Science and Pollution Research - Pollution control policies have achieved remarkable results in China. However, industrial firms still lack enthusiasm for technological innovation to...  相似文献   
975.
Environmental Science and Pollution Research - Camphor wood is welcomed by museums due to its insect-repelling effect but the smell indicates a potential risk to the collections. In order to judge...  相似文献   
976.
Environmental Science and Pollution Research - In the present study, occurrence of arsenic (As) and lead (Pb) is reported in rural and urban household dust (floor and AC filter dust) of the Kingdom...  相似文献   
977.
Ma H  Wang M  Yang R  Wang W  Zhao J  Shen Z  Yao S 《Chemosphere》2007,68(6):1098-1104
Radiation-induced degradation of Congo Red (an azo dye) in aqueous solution was studied both with steady-state radiolysis and time-resolve techniques of pulse radiolysis and laser flash photolysis. Decomposition and mineralization of Congo Red by gamma-rays was investigated with the changes of absorption spectra, degradation efficiency, TOC removal and pH changes of the solutions in different irradiation systems. The main radiolytic products resulting from steady-state radiolysis of Congo Red were examined by HPLC and LC-MS. Complete degradation of Congo Red was observed at different absorbed doses under diverse irradiation condition. The TOC removal of the solutions saturated with O2 or N2O reached 76% and 86% at the absorbed dose of 11.9 kGy, respectively. Pulse radiolysis and laser flash photolysis experiments were carried out to study the reaction of Congo Red with e(aq)- and ()OH. The reaction rate constants were determined.  相似文献   
978.
Microbially mediated bioreduction of iron oxyhydroxide plays an important role in the biogeochemical cycle of iron.Geobacter sulfurreducens is a representative dissimilatory ironreducing bacterium that assembles electrically conductive pili and cytochromes.The impact of supplementation withγ-Fe_2O_3 nanoparticles(NPs)(0.2 and 0.6 g)on the G.sulfurreducens-mediated reduction of ferrihydrite was investigated.In the overall performance of microbial ferrihydrite reduction mediated byγ-Fe_2O_3 NPs,stronger reduction was observed in the presence of direct contact withγ-Fe_2O_3 NPs than with indirect contact.Compared to the production of Fe(Ⅱ)derived from biotic modification with ferrihydrite alone,increases greater than 1.6-and 1.4-fold in the production of Fe(Ⅱ)were detected in the biotic modifications in which direct contact with 0.2 g and 0.6 gγ-Fe_2O_3 NPs,respectively,occurred.X-ray diffraction analysis indicated that magnetite was a unique representative iron mineral in ferrihydrite when active G.sulfurreducens cells were in direct contact withγ-Fe_2O_3 NPs.Because of the sorption of biogenic Fe(Ⅱ)ontoγ-Fe_2O_3 NPs instead of ferrihydrite,the addition ofγ-Fe_2O_3 NPs could also contribute to increased duration of ferrihydrite reduction by preventing ferrihydrite surface passivation.Additionally,electron microscopy analysis confirmed that the direct addition ofγ-Fe_2O_3 NPs stimulated the electrically conductive pili and cytochromes to stretch,facilitating long-range electron transfer between the cells and ferrihydrite.The obtained findings provide a more comprehensive understanding of the effects of iron oxide NPs on soil biogeochemistry.  相似文献   
979.
浙江金洲集团股份有限公司是一家大型管道专业制造企业 ,是全国最大的管道科研生产基地之一 ,其主要防腐产品大口径涂敷钢管、钢塑复合管、铝塑复合管和热浸镀锌钢管畅销国内 2 0多个省市 ,产量位居同行业榜首。公司在取得经济效益的同时 ,将环保工作与创业宗旨、企业命运紧密结合 ,把节能降耗、清洁生产、污染防治、生态保护作为工作重点 ,使经济建设和环境保护同步规划、同步发展、同步提高。从建厂初期的简单设施中萌芽环保意识进展到 1 997年已超前控制烟尘排放 ;从 1 985年靠集资搞环保发展到现今投入近千万资金积极遵循环保这个“导航…  相似文献   
980.
汉江流域丹江口库区是南水北调中线工程的水源地,其周边及上游流域生态环境对于保证库区生态安全具有重要意义。利用汉江上游流域的数字高程模型进行子流域划分,分析了汉江上游及子流域的土地利用/土地覆盖特征,并结合利用土壤侵蚀强度分级标准和数字高程图(DEM),对流域的水土流失进行初步估算。研究结果表明,除丹江口库区周边及汉中盆地的森林灌丛覆盖率相对较低之外,其它亚流域的森林覆盖率都在50%以上。上游中部地区的水土流失现象较为严重,尤其是大巴山的北坡和秦岭的旬河流域,而汉中盆地与丹江口库区周边的水土流失相对较轻。研究结果可为流域的环境治理及生态恢复提供支撑,对南水北调中线工程水源地保障具有重要意义。  相似文献   
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