Assessment of heavy metal pollution from a Fe-smelting plant in urban river sediments using environmental magnetic and geochemical methods

Environmental magnetic proxies provide a rapid means of assessing the degree of industrial heavy metal pollution in soils and sediments. To test the efficiency of magnetic methods for detecting contaminates from a Fe-smelting plant in Loudi City, Hunan Province (China) we investigated river sediments from Lianshui River. Both magnetic and non-magnetic (microscopic, chemical and statistical) methods were used to characterize these sediments. Anthropogenic heavy metals coexist with coarse-grained magnetic spherules. It can be demonstrated that the Pollution Load Index of industrial heavy metals (Fe, V, Cr, Mo, Zn, Pb, Cd, Cu) and the logarithm of saturation isothermal remanent magnetization, a proxy for magnetic concentration, are significantly correlated. The distribution heavy metal pollution in the Lianshui River is controlled by surface water transport and deposition. Our findings demonstrate that magnetic methods have a useful and practical application for detecting and mapping pollution in and around modern industrial cities.     

A sensitive monoclonal antibody-based enzyme-linked immunosorbent assay for chlorpyrifos residue determination in Chinese agricultural samples

A monoclonal antibody-based competitive antibody-coated enzyme-linked immunosorbent assay (ELISA) was developed and optimized for determining chlorpyrifos residue in agricultural products. The IC(50) and IC(10) of this ELISA were 3.3 ng/mL and 0.1 ng/mL respectively. The average recoveries in six agricultural products were between 79.5% and 118.0%, with the intra-assay coefficient of variation being less than 8 %. The limit of detection for all tested products was 30 ng/g. To the best of our knowledge, this assay has the best specificity among all the published research on ELISAs for chlorpyrifos.     

Occurrence of diarrheagenic Escherichia coli genes in raw water of water treatment plants

Purpose

The high incidences of waterborne diseases are frequently associated with diarrheagenic Escherichia coli (DEC). DEC may pose a health risk to people who contact surface water for recreation or domestic use. However, there is no published report on the monitoring of DEC in drinking water sources in Taiwan. In this study, the occurrence of DEC genes in raw water for water treatment plants in Taiwan was investigated.

Method

Raw water samples were taken from water treatment plants adjacent to the Kaoping River in southern Taiwan. Each water sample was treated with membrane filtration followed by DNA extraction from the concentrate and concentrate enrichment, respectively. The target genes for various DEC strains of genes were identified, including enteroaggregative E. coli (EAEC), enterohemorrhagic E. coli (EHEC), enteroinvasive E. coli (EIEC), enteropathogenic E. coli (EPEC), and enterotoxigenic E. coli (ETEC).

Results

Among 55 water samples analyzed, DEC genes were detected in 16 (29.1%) samples. Strain-specific genes for EAEC, EHEC, EIEC, and EPEC were found in the percentages of 3.6%, 10.9%, 9.1%, and 9.1%, respectively. The specific gene for ETEC is not detected in the study. By looking at the presence/absence of specific genes and water sample characteristics, water temperature was found to differ significantly between samples with and without EHEC gene. In addition, pH levels differed significantly for EHEC and EPEC presence/absence genes, and turbidity was significantly different for water with and without EPEC genes.

Conclusion

DEC genes were detected in 29.1% of the raw water samples in the study location. The potential health threat may be increased if the treatment efficiencies are not properly maintained. Routine monitoring of DEC in drinking water sources should be considered.     

Polybrominated diphenyl ethers (PBDEs) and indicator polychlorinated biphenyls (PCBs) in marine fish from four areas of China

The levels of polybrominated diphenyl ethers (PBDEs) and indicator polychlorinated biphenyls (PCBs) were determined in marine fish from four areas of China (South China Sea, Bohai Sea, East China Sea, and Yellow Sea) using GC/NCI-MS and GC/ITMS, respectively. Total concentrations of eight PBDEs (BDE-28, 47, 99, 100, 153, 154, 183 and 209) in all samples ranged from 0.3 ng g⁻¹ ww (wet weight) to 700 ng g⁻¹ ww, with median and mean values of 85 ng g⁻¹ ww and 200 ng g⁻¹ ww, respectively. BDE-209 and BDE-47 were the major congeners in all samples, contributing 54% and 19% to the total concentration, respectively. The sum of seven indicator PCB levels (CB-28, 52, 101, 118, 138, 153, and 180) ranged from 0.3 ng g⁻¹ ww to 3.1 μg g⁻¹ ww, with median and mean values of 6.4 ng g⁻¹ ww and 398 ng g⁻¹ ww, respectively. High contributions of CB-138 (32%) and CB-153 (25%) were found in all samples. In general, pollutants measured in this study were at high levels when compared with previous studies from other regions in the world. The relative abundance of BDE-209 may suggest that deca-BDE sources existed in studied area. And principal component analysis (PCA) showed that there were other PBDE sources in Yellow Sea. The pattern and PCA showed that PCB pollutions came from similar sources in the studied areas. In addition, concentrations of ∑₇PBDEs (u/209) were strongly correlated with those of ∑₇PCBs in all fish (r = 0.907, n = 44).     

杂多酸水溶液脱除烟气中SO2的性能研究

合成了H3PMo12O40、H4SiW12O40、H3PW12O40、H4PMo11VO40、H5PMo10V2O40和H6PMo9V3O406种杂多酸,分别采用红外光谱（FT-IR）和X射线衍射（XRD）表征杂多酸的结构,并采用气相色谱仪对6种杂多酸水溶液进行脱硫实验测试。实验结果表明：制备的6种杂多酸具有良好的Keggin型结构;H3PMo12O40、H3PW12O40和H4SiW12O40的3种水溶液中,磷钼杂多酸的脱硫性能最好,脱硫率在120 min时可达到16.38%;不同比例的多原子也会使杂多酸有不同的脱硫性能,脱硫性能顺序为：H6PMo9V3O40〉H5PMo10V2O40〉H4PMo11VO40;且6种杂多酸的脱硫稳定性的顺序为：H4PMo11VO40〉H6PMo9V3O40〉H3PMo12O40〉H5PMo10V2O40〉H4SiW12O40≈H3PW12O40。     

高温烧结磷石膏钙渣制备轻质碳酸钙

以磷石膏钙渣为原料,通过高温煅烧,然后经消化、精制、碳化,制成轻质碳酸钙产品.研究结果表明:高温煅烧的最佳温度为 1 000 ℃,最佳煅烧时间为 1.0 h;沉淀反应的初始反应温度为 60 ℃,Ca(OH)2乳液质量浓度为 70 g/L,CO2流量为 1.8 L/h.制备的轻质碳酸钙产品各项指标均达到 HG/T2226...     

树脂吸附-Fenton 试剂氧化法预处理炼油碱渣废水

采用树脂吸附-Fenton 试剂氧化组合工艺对某炼油企业炼油碱渣废水进行预处理.实验确定的最佳工艺条件为:3 种树脂串联吸附,废水流量0.33 mL/ min,H2O2加入量0.20 mol / L,n（H2O2）1 n（Fe2 +）= 12,Fenton 试剂氧化进水pH 3,Fenton 试剂氧化反应时间120 m...     

Decomposition of dichloromethane and in situ alkali absorption of resulting halogenated products by a packed-bed non-thermal plasma reactor

For an effective decomposition and removal of organic halogenated compounds, a packed-bed non-thermal plasma reactor with in situ absorption of the resulting halogenated products by alkaline sorbent incorporated was proposed. In the plasma reactor, α-Al₂O₃ particles of 1 and 3 mm (mean particle diameter) were packed as solid dielectric medium to enhance the plasma power density in the reactor. Further, alkaline sorbent of Ca(OH)₂ was doped onto the surface of α-Al₂O₃ particles, in order to remove halogenated products by in situ absorption with Ca(OH)₂. A high-voltage and high-frequency pulsed power of −15 to 15 kV and 1 kHz was applied to the wire electrode of the plasma reactor by means of a DC power source. In the present study, as the sample of an organic halogenated compound that is most popularly used, we selected dichloromethane (CH₂Cl₂), and 500 ppm of the initial concentration of CH₂Cl₂ was fed into the reactor accompanied by air at a fixed flow rate of 500 × 10⁻⁶ m³ min⁻¹ at room temperature. As a result, it was recognized that the amount of CH₂Cl₂ decomposed by non-thermal plasma in an α-Al₂O₃ particle bed increased with an increase in plasma input power. The ratio of decomposition of CH₂Cl₂ was almost 100% at 13 kV of electric power and 1 kHz frequency, and CO₂, CH₃Cl, COCl₂, HCl, and Cl₂ were observed as the major reaction products. On the other hand, when CH₂Cl₂ was introduced into the plasma reactor where α-Al₂O₃ particles doped with Ca(OH)₂ were packed, the ratio of decomposition of CH₂Cl₂ became higher, compared to the case that α-Al₂O₃ particles were not doped with Ca(OH)₂. Moreover, there were no halogenated by-product gases detected in the outlet gas from the reactor. As the solid reaction products, CaClOH and Ca(ClO)₂·4H₂O were detected on Ca(OH)₂ by X-ray diffraction. From these findings, it was recognized that CH₂Cl₂ was decomposed more effectively without producing unwanted harmful halogenated by-products in the proposed non-thermal plasma reactor where α-Al₂O₃ particles doped with Ca(OH)₂ sorbent were packed.     

探索城市再生资源回收利用的新型模式

以结合本地区实际探索制度创新模式为切入点,介绍多元投资再生资源回收利用龙头企业基地建设项目策划团队的总体思路:尝试创办社区网络回收二手电器登记调剂中心;论证绿色拆解与再制造关联板块基础设施共享的可行性方案;强调推动资源循环利用产业发展不可缺少的管理工具是信息服务管理网络和监管信息系统项目建设。     

Ce-Sn-W-O_x催化剂的配伍优化及脱硝影响因素

采用共混热解法制备系列Ce-Sn-W-Ox复合氧化物,用于NH3选择性催化还原NO。通过正交实验优化CeSn-W-Ox配方,采用环境扫描电镜(ESEM)、X-射线衍射仪(XRD)等表征分析催化剂的微观形貌和固相结构,确立Ce-Sn-WOx最佳配比及结构形貌。结果表明,以粒度为5~8 mm的堇青石瓷片担载分散Ce-Sn-W-Ox,进行NH3-SCR脱除NO,当Ce/Sn/W元素摩尔比为1∶0.8∶0.6时,Ce Sn0.8W0.6Ox/堇青石NH3-SCR脱除NO效果最好。当空速为7 200 h-1,催化剂在252~426℃内脱除NO效率均大于94%。重点考察了反应空速(GHSV)、水蒸气(H2O)、SO2等对Ce Sn0.8W0.6Ox/堇青石NH3-SCR脱除NO活性的影响。研究表明,空速低于10 000 h-1时,催化剂脱硝活性受空速影响小;单独通入5%H2O对催化剂脱硝活性基本没有影响;单独通入429 mg/m3SO2导致催化剂活性略有降低;同时通入429 mg/m3SO2和5%H2O,催化剂脱硝活性下降至85.33%,除去SO2和H2O后,催化剂活性又能明显回升。