Simultaneous sorption of aqueous phenanthrene and phosphate onto bentonites modified with AlCl3 and CTMAB

The purpose of this work is to synthesize a new type of bentonite sorbent that can simultaneously remove both organic compounds and phosphate from water. Inorganic-organic bentonites (Al-CTMAB-Bent) were synthesized by modifying bentonites with both AlCl₃ and cetyltrimethyl ammonium bromide (CTMAB). Simultaneous sorption of aqueous phenanthrene and phosphate onto Al-CTMAB-Bent was examined. Removal rates of phenanthrene and phosphate from water reached 96.3% and 90.2%, respectively, at their respective initial concentrations of 1 mg/L and 5 mg/L and the added amount of Al-CTMAB-Bent was 1.25 g/L. The residual turbidity of the Al-CTMAB-Bent suspension decreased 81.4% compared to that of organobentonite suspension after a 1 h settling time. Thus, inorganic-organic bentonite can be used to treat wastewater containing both organic pollutants and phosphate. Translated from Environmental Science, 2006, 27(1): 91–94 [译自: 环境科学]     

Pollution survey of carbonyl compounds in train air

The train is an important vehicle in China, but its air quality has important impacts on passengers’ health. In this work, pollution from carbonyl compounds was measured in the air of six trains. The objectives of this work were to investigate carbonyl compound levels in selected air from trains, identify their emission sources, and assess the intake of carbonyl compounds for passengers. The methods for sampling and analyzing 10 carbonyl compounds such as formaldehyde, acetaldehyde, acrolein, acetone, propionaldehyde, crotonaldehyde, butyraldehyde, benzaldehyde, cyclohexanone, and valeraldehyde in indoor air were proposed with the sampling efficiency, recovery, and detection limit being 92%–100%, 91%–104%, and 0.26–0.82 ng/m³, respectively. It was indicated that the total concentrations of carbonyl compounds were 0.159–0.2828 mg/m³ with the average concentration of 0.2330 mg/m³. The average concentrations of form aldehyde, acetaldehyde and acetone were 0.0922, 0.0499, and 0.0580 mg/m³, accounting for 42.6%, 21.4%, and 24.9% of the total concentrations of carbonyl compounds, respectively. The carbonyl compounds probably came from woodwork and cigarette smoking. The intake of carbonyl compounds for the passengers was approximately 0.043–0.076 mg/h. The carbonyl compounds in train air could be harmful to human health. Translated from Environmental Science, 2006, 27(1) 91–94 [译自: 环境科学]     

典型北方高碱度微污染水体强化混凝的示范研究

以高碱度、受有机物污染的典型北方水体为例,探索适宜的强化混凝技术.在水质调查的基础上,提出适合水质特征的强化混凝目标.研究了高碱度水体强化混凝技术方法.研究表明,可以通过3条技术途径提高水体中有机物的去除效率.其一在混凝前优化pH,促进絮凝剂水解形成中聚体,AlCl3在pH 6左右,FeCl3在pH 5左右时,有机物去除率可以提高一倍左右;其二是强化沉淀软化;其三是絮凝剂优化.结合我国实际情况,通过对传统絮凝剂进行改性,研制出了适合我国北方水质特征的高效絮凝剂,能较传统絮凝剂将有机物去除率提高30%以上.     

Population growth, management and environmental degradation in China

Environmental problems in China can be divided into two large classes: pollution and destruction of natural environment. Environmental degradation is particularly serious in areas with rapid population growth. In this paper, some of China's major environmental problems, particularly those concerned with land, forests, and continental waters are introduced in order to see how population growth and management have affected these resources over the past few decades. It is also explained how the Chinese plan to cope and eventually solve these problems.     

几种海洋微藻对水中三丁基锡化合物的迁移和转化作用

实验表明，在半抑制效应浓度下纤弱角毛藻，扁藻，三角褐指藻对三丁基锡均有瞬时强吸附作用，其后，微藻对三丁基锡的吸收可单室生物积累模型描述，根据模型曲线拟合求出其总吸收饱和浓度和生物排出速常数，微藻对三丁基锡的生物富集因子高达１０＾４－１０＾５，主要取决于高比表面，高分配比和高摄取速率，７２ｈ纤弱角毛藻对三丁基锡的生物降解率在５％左右。     

复合氧化物汽车尾气净化催化剂抗SO2中毒机理研究

复合氧化物催化剂(ASC)具有较高的活性和良好的抗SO_2中毒性能.用IR、XPS、TPD等技术研究了该催化剂抗SO_2中毒机理,结果表明,与易失活催化剂相比,ASC经500h反应(反应气含SO_2约20ppm),其活性组分价态无显著变化,仅表面发生SO_2的化学吸附,经与约500ppm的SO_2作用20h后,发现仅有少量SO_4~(2-)形成.这是由于在ASC催化剂中添加了特殊助剂,而使催化剂活性组分得到保护的缘故.     

多环芳烃的分配系数与双区理论

以双区理论为基础,提出了多环芳烃的致癌性与其分配系数之间的定量关系方程,并利用该方程计算了77个多环芳烃的致癌性。计算值与实验值基本符合。     

速灭菊酯在水稻-水-鱼系统中的动态

采用同位素示踪技术和模拟生态系统试验法,对水田施用速灭菊酯后对邻近水域的污染、水域中鱼类对速灭菊酯残留物的浓缩和排除等进行了研究,结果表明,在田表水中,残留物浓度随处理后时间而迅速降低。水系中淤泥对水中残留物有明显的吸附净化作用,鱼对水中速灭菊酯残留物的摄取和排除均很迅速。 用二室模型对速灭菊酯残留物在田表水中的消失、用一级输入和输出的单室模型对鱼体中残留物浓度随时间的变化动态研究表明,在田表水中,土壤对水中残留物起着强烈的吸附净化作用;在水系中,鱼体中残留物浓度的消长主要取决于残留物自身在水中的消失速率,只是在前期同时依赖于鱼体对残留物的排除效应,鱼体的摄入常数只对鱼体累积浓度最大值及到达最大值的时间T_m产生影响。     

Transcervical CVS sample size: Correlation with placental location,cytogenetic findings,and pregnancy outcome

Data from 2907 transcervical CVS cases performed on singleton pregnancies were reviewed retrospectively and villus sample size was correlated with cytogenetic results, placental location, maternal age at the expected date of confinement (EDC), gestational age at the time of sampling, birth weight, gestational age at the time of delivery, and pregnancy outcome. No correlation was noted between villus sample size and maternal age, gestational age at sampling, gestational age at delivery, birth weight, or pregnancy outcome. An inverse correlation between villus sample size and percentage of abnormal cytogenetic findings was statistically significant (X² = 8·53, p <0·01). The percentage of small samples was greater when the placenta was anterior, lateral, or fundal than when the placenta was posterior.     

炼厂含油水罐事故分析与防范措施研究

炼化企业中有大量含油水罐,这些储罐中含硫、含油,固有风险很高,事故频发,有必要对各类污水罐事故进行分析和研究,找出共性的问题,提出解决方案和事故防范对策。通过对所搜集到的2009-2012年发生的36起含油水罐事故,从储罐类型、事故类型、点火源、操作阶段等方面进行统计分析,对案例进行深入剖析,找出了污水罐在设计、设备防腐以及操作管理中存在问题,并针对问题提出了相应的建议措施。