PPCPs and heavy metals from hydrothermal sewage sludge-derived biochar: migration in wheat and physiological response

Environmental Science and Pollution Research - Once the sludge was directly used in the farmland, it will have a negative impact on human health through the food chain because sludge contains...     

溶解氧对人工湿地处理受污染城市河流水体效果的影响

研究了溶解氧在人工湿地中的分布对受污染城市河流水体处理效果的影响规律及其意义,为城市受污染景观水体处理或雨水处理人工湿地的工程设计提供有效的自然复氧估算方法和设置措施.结果表明,由于自然复氧不利引起的溶解氧不足(<2 mg/L)是导致人工湿地出水水质恶化的主要原因.自然跌水是一种有效的人工湿地充氧方式,其充氧效果可用氧亏比r根据水温、水质以及充氧形式等外部条件参数进行估算.推流态的湿地床内,溶解氧分布与生物量分布以及有机物的去除规律呈现明显的相关性,而对TP沿程去除速率影响不大.设置多级多段跌水有利于均衡湿地床填料内的溶解氧分布,促进硝化反应,保证出水水质.     

危险化学品活性反应危害及混配危险的规则研究(Ⅻ)

第四十五类 金属卤化物 活性特点: 金属卤化物具有MX-n基团,按结构可分为离子型和共价型金属卤化物.在金属卤化物中,一般说,低价态的金属氟化物大都是离子型卤化物(因氟离子的变形性弱,只有高价金属的氟化物,如六氟化铀才成为共价化合物).     

煤矿职工教育信息管理系统的开发

为了加强煤矿企业的安全管理 ,降低事故频率 ,提高劳动生产率 ,笔者详细介绍了用VFP软件开发的煤矿职工教育信息管理系统。实践证明该系统具有安装方便、界面友好、功能齐全等特点 ,在煤矿企业有推广应用价值。     

Studies of Thermal Transformations of Humic and Fulvic Acids in Soils I. Infrared Spectroscopy and Temperature-Programmed Pyrolysis Mass Spectrometry

Temperature-programmed pyrolysis mass spectrometry and Fourier-transform infrared spectroscopy have been used to monitor structural changes of humic and fulvic acids isolated from soils in China, in the temperature range of 25-550°C. in this work, we found that decarboxylation is obvious as the main reaction with dehydration reaction from 150°C to 400°C, the anhydride can be identified from FT-IR spectra at temperature range from 200°C to 400°C; there are evident changes of the aromatic nucleus of humic and fulvic acids above 400°C, even remaining up to 550°C. Besides, some changes of adsorption water can be distinguished before 200°C, and the mass signal of sulphur dioxide was detected.     

重庆地区区域灰霾观测初步研究

2012年灰霾试点监测结果表明,灰霾日天数有明显减少。细颗粒物(PM2.5)浓度限值增加,使仅因重庆城市地域和气候原因造成部分相对湿度较低,而实际环境空气质量较好的灰霾日排除在外,更客观评价灰霾日发生规律。结合气象条件和颗粒物质量浓度对比情况表明,局域气候条件的变化将促使PM2.5和PM1吸湿增长明显,一定程度上促使粗颗粒物PM10质量浓度增加,局域污染物传输扩散不利,能见度减低,灰霾现象频增。     

北塘排污河天津中心城区段恶臭污染调查与分析研究

为研究天津市中心城区北塘排污河恶臭污染特征,沿北塘排污河布设5个采样点位,分别在夏、秋、冬三季进行了系统采样.北塘排污河夏、秋、冬三季总检出浓度为23.842 5 mg/m^3,夏季（9.273 1mg/m^3）＞冬季（8.388 4 mg/m^3）＞秋季（6.181 0 mg/m^3）,靖江桥和兵营桥两个点位受赵沽里泵站出水水质的影响较大,对周围的恶臭污染程度更为严重.北塘排污河污染物质总检出浓度组成特征：无机气体＞含氧烃＞烷烃＞芳香烃＞卤代烃＞烯烃＞硫化物,共检出物质67种,检出率大于70％的污染物共30种,广泛存在的物质为11种,主要恶臭污染物为少量的含氧烃、无机气体和硫化物,乙醛、丙酮、硫化氢和甲硫醇为北塘排污河主要恶臭污染物.     

Ti02光催化剂的掺杂改性和固定化研究

纳米TiO2作为光催化剂,由于其化学性质稳定、无毒、价廉等优点,使得纳米TiO2光催化氧化技术在环境领域具有广阔的应用前景,而针对其对可见光利用率低,光生电子一空穴对易复合,在使用过程中回收难,光催化效率不高等问题,近年来科研人员致力于Ti02光催化剂的改性和固定化研究。本文介绍了掺杂改性的不同方法及负载技术的研究进展,其中包括贵金属沉积、金属离子掺杂、非金属掺杂、共掺杂、表面光敏化、复合半导体等,并提出了TiO2光催化剂今后的研究方向及存在的问题。     

Treatability of volatile chlorinated hydrocarbon-contaminated soils of different textures along a vertical profile by mechanical soil aeration: A laboratory test

Mechanical soil aeration is a simple, effective, and low-cost soil remediation technology that is suitable for sites contaminated with volatile chlorinated hydrocarbons(VCHs). Conventionally, this technique is used to treat the mixed soil of a site without considering the diversity and treatability of different soils within the site. A laboratory test was conducted to evaluate the effectiveness of mechanical soil aeration for remediating soils of different textures(silty,clayey, and sandy soils) along a vertical profile at an abandoned chloro-alkali chemical site in China. The collected soils were artificially contaminated with chloroform(TCM) and trichloroethylene(TCE). Mechanical soil aeration was effective for remediating VCHs(removal efficiency 98%). The volatilization process was described by an exponential kinetic function.In the early stage of treatment(0–7 hr), rapid contaminant volatilization followed a pseudofirst order kinetic model. VCH concentrations decreased to low levels and showed a tailing phenomenon with very slow contaminant release after 8 hr. Compared with silty and sandy soils, clayey soil has high organic-matter content, a large specific surface area, a high clay fraction, and a complex pore structure. These characteristics substantially influenced the removal process, making it less efficient, more time consuming, and consequently more expensive. Our findings provide a potential basis for optimizing soil remediation strategy in a cost-effective manner.