Characteristics of sewage sludge and distribution of heavy metal in plants with amendment of sewage sludge

In order to better understand land application of sewage sludge, the characterization of heavy metals and organic pollutants were investigated in three different sewage sludges in Shanghai City, China. It was found that the total concentrations of Cd in all of sewage sludge and total concentrations of Zn in Jinshan sewage sludge, as well as those ofZn, Cu, and Ni in Taopu sludge are higher than Chinese regulation limit of pollutants for sludge to be used in agriculture. Leachability of rig in all of studied samples and that of Cd in Taopu sewage sludge exceed the limit values of waste solid extraction standard in China legislation. Based on the characteristics for three kinds of sewage sludge, a pot experiment was conducted to investigate the effect of soil amended with Quyang sewage sludge on the accumulation of heavy metalo.by Begonia semperfloreas-hybr; Ophiopogon japonicas （L.F.） Ker-Gaw; Loropetalum chindense-var, rubrum; Dendranthema morifolium; Viola tricolor; A ntirrhinum majas; Buxas radicans Sieb; Viburnum macrocephalum; Osmanthas fragrans Lour; Cinnamomum camphora siebold and Ligustrum lucidum ait. Results showed that 8 species of plant survived in the amended soil, and moreover they flourished as well as those cultivated in the control soil. The heavy metal concentration in plants varied with species, As, Pb, Cd and Cr concentration being the highest in the four herbaceous species studied, particularly in the roots of D. morifolium. These plants, however, did not show accumulator of As, Pb, Cd and Cr. The highest concentration of Ni and Hg was found in the roots ofD. morifolium, followed by the leaves ofB. semperflorens-hybr. Levels of Zn and Cu were much higher in D. morifolium than in the other plant species. D. morifolium accumulated Ni, Hg, Cu and Zn, which may contribute to the decrease of heavy metal contents in the amended soil. Treatment with sewage sludge did not significantly affect the uptake of heavy metals by the L. chindense-var, rubrum, however, it significantly affected the uptake of heavy metals by D. morifolium.     

Degradation of 2,4-dichlorophenoxyacetic acid in water by ozone-hydrogen peroxide process

IntroductionAt present, several types of organic pollutantsreferred to as environmental endocrine disruptors(ED) have been suggested to be associated withabnormal sexual development (Hu, 2000). It wasreported that the ED led to the decline of reproductive…     

Process of rice straw degradation and dynamic trend of pH by the microbial community MC1

The process of the rice straw degradation in the fermentor with aeration at 290 ml/h was studied. The results of dissolved oxygen （DO） indicated that the optimum DO during cellulose degradation by microbial community MC1 ranged from 0.01 to 0.12 mg/L. The change model ofpH values was as follows： irrespective of the initial pH of the medium, pH values decreased rapidly to approximate 6.0 after being inoculated within 48 h when cellulose was strongly degraded, and then increased slowly to 8.0--9.0 until cellulose was degraded completely. During the degradation process, 15 kinds of organic compounds were checked out by GC-MS. Most of them were organic acids. Quantity analysis was carried out, and the maximum content compound was ethyl acetate which reached 13.56 g/L on the day 4. The cellulose degradation quantity and ratio analyses showed that less quantity （under batch fermentation conditions） and longer interval （under semi-fermentation conditions） of rice straw added to fermentation system were contributed to matching the change model of pH, and increasing the quantity and ratio of rice straw degradation during cellulose degrading process. The highest degradation ratio was observed under the condition office straw added one time every five days （under semi-fermentation conditions）.     

HDTMA改性粘土吸附固定沉积物间隙水中多环芳烃的模拟研究

选用经过十六烷三甲基溴化铵(HDTMA-Br)改性的粘土矿物为吸附剂,探讨其对水中多环芳烃类有机污染物的吸附性能。结果表明,HDTMA改性土吸附固定水中多环芳烃的能力比天然沉积物要高得多且吸附稳定。本文还讨论了环境温度、pH值、盐度、振荡时间、污染物初始浓度以及投土量对吸附性能的影响以确定吸附的适宜条件。根据实验结论,将HDTMA改性土投到实际间隙水样品中,经过充分的吸附,结果显示,经HDTMA改性粘土吸附后的间隙水中多环芳烃的含量均在检出线以下,说明HDTMA改性土可以有效地吸附固定沉积物间隙水中的多环芳烃,降低其迁移性,防止其释放产生二次污染。     

如何发挥环境应急监测在突发环境污染事故中的作用

为降低突发性环境污染事故对人类健康的威胁和对生态环境的破坏,提出研究如何发挥环境应急监测在突发环境污染事故中的作用。以某起突发环境污染事故展开研究,先确定污染事故应急监测流程,在遵守应急监测原则下采取紧急措施,并对污染地区的水质及空气实施采样检测,结果均在标准范围内。然后再对事发地跟踪检测3天,最后1天均显示无污染物质,危险解除。通过本文的研究可以更好地理解环境应急监测的流程、方法以及它们对于保护环境的重大意义。这将有助于更好地进行未来的环保监管。     

粉煤灰最大往返剪切作用面上应变破坏标准的应力条件

基于文献[1]提出的最大往返剪切作用面上的液化应力条件和粉煤灰的动三轴试验数据,运用回归分析方法拟合曲线及相关参数建立了粉煤灰的破坏应力条件,并应用F检验法对参数的回归效果进行了检验,检验结果表明参数的回归效果高度显著。得出的破坏应力条件表明初始剪应力与动剪应力的倒数间并不呈线性关系,而是二次多项式关系,这与张克绪所提出的应力条件存在着差异。因此,可初步认为张克绪的液化应力条件不能直接运用于粉煤灰。     

张鸿翼中国地震现场考察的先行者

张鸿翼,字君翔,云南保山县人, 生卒年不详。张鸿翼天资聪明,17岁时应县、府院试均获第一。1904年考入北京京师大学堂,毕业授内阁中书,后不久离京回滇。民国初,历任云南省教育总会会长、云南孔教会附设国学社讲习长、省立甲种农业学校校长、省督军公署秘书、云南农业中学校长、云南高等学校校长、教育研究会博物系主任。 1922年4月赴美国芝加哥、纽约、华盛顿等地考察,后入加州大学公费留学。回国后,历任省公署顾问、代理交通厅长、     

亲历巴基斯坦地震救援(二)

应巴基斯坦政府的请求,第二批中国国际救援队队员,带着祖国人民的重托于2005年10月28日中午12时乘包机飞往巴基斯坦执行以医疗救助为主的救援任务。这时距我们第一批国际救援队队员归来仅仅8天的时间。 10月28日下午三点半,我们抵达伊斯兰堡机场,中国驻巴基斯坦张春祥大使、巴劳工部部长和有关人员在机场迎接我们,随后妥善安排了卸货、人员运送车辆等。我还是负责全体救援队员     

唐山抗震精神的时代内涵

唐山抗震精神唐山抗震精神是指唐山大地震发生时及震后救灾活动中支撑、激励、鼓舞和引导唐山人奋勇崛起,艰苦卓绝,最终战胜地震灾害,重建家园的巨大精神力量。     

立足保障提高防震减灾能力

近年来,青岛市重视防震减灾工作,围绕地震监测预报、震害防御、应急救援三大工作体系建设,积极推动防震减灾工作不断发展。进一步提高了防震减灾综合能力。逐步完善机构设置1997年,设立青岛市地震局,专门负责防震减灾行政管理;2001年,在市级机关机构改革中,将市地震局设为市政府直属部门,从市科技局所属的二级局升格为正局级部门,主管全市防震