摘要：
Chlorinated volatile organic compounds (Cl-VOCs) contamination has been recognized as one of the major problem in worldwide due to natural and anthropogenic activities. Recently, several treatment technologies (e.g., adsorption for broader concentration Cl-VOCs, catalytic combustion for high concentration (>500 ppm), advanced oxidation, electrochemical method, metal method and photo catalytic method for low concentration (<500 ppm)) have been applied for Cl-VOCs elimination. In this review, an extensive list of every method from literatures is compiled, and their capacities under various conditions are presented. However, there is still need to find out the practical technologies on commercial scale, leading to improvement of environmental pollution control. (C) 2018 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.
摘要：
Xiawanggang River region is considered to be one of the most polluted areas in China due to its huge amount discharge of pollutants and accumulation for years. As it is one branch of Xiang River and the area downstream is Changsha city, the capital of Hunan Province, the ecological niche of Xiawangang River is very important. The pollution treatment in this area was emphasized in the Twelfth Five-Year Plan of Chinese government for Xiang River Water Environmental Pollution Control. In order to assess the heavy metal pollution and provide the base information in this region for The Twelfth Five-Year Plan, contents and fractions of four heavy metals (Cd, Cu, Pb and Zn) covering both sediments and soils were analyzed to study their contamination state. Three different indexes were applied to assess the pollution extent. The results showed this area was severely polluted by the four heavy metals, and the total concentrations exceeded the Chinese environmental quality standard for soil, grade III, especially for Cd. Moreover, Cd, rated as being in high risk, had a high mobility as its great contents of exchangeable and carbonates fractions in spite of its relative low content. Regression analysis revealed clay could well explain the regression equation for Cd, Cu and Zn while pH and sand could significantly interpret the regression equation for Pb. Moreover, there was a significant correlation between Non-residual fraction and I(geo) for all the four metals. Correlation analysis showed four metals maybe had similar pollution sources.
摘要：
A novel biosorbent, polyvinyl alcohol (PVA)-immobilized Phanerochaete chrysosporium, was applied to the bioremediation of composite-polluted wastewater, containing both cadmium and 2,4-dichlorophenol (2,4-DCP) The optimum removal efficiency achieved was 78% for Cd(II) and 95.4% for 2,4-DCP at initial concentrations of 20 mg/L Cd(II) and 40 mg/L 2,4-DCP. PPBs had significantly enhanced the resistance of P. chrysosporium to 2,4-DCP, leading to the degradation rates of 2,4-DCP beyond 90% with varying initial 2,4-DCP concentrations. This research demonstrated that 2,4-DCP and secreted proteins might be used as carbon and nitrogen sources by PVA-immobilized P. chrysosporium beads (PPBs) for Cd(II) removal. Fourier transform infrared spectroscopy analysis showed that hydroxyl and carboxyl groups on the surface of PPBs were dominant in Cd(II) binding. The mechanism underlying the degradation of 2,4-DCP into fumaric acid and 1-hexanol was investigated. The adsorption-desorption studies indicated that PPBs kept up to 98.9% of desorption efficiency over three cycles. (C) 2015 Elsevier B.V. All rights reserved.
通讯机构：
[Xie, Tengfeng] Jilin Univ, Coll Chem, Qianjin St 2699, Changchun 130012, Jilin, Peoples R China.
关键词：
Gas sensor;Photocatalysis;Photocurrent;ZnO;Formaldehyde
摘要：
The ZnO nanorods with different diameters (similar to 300, 100, 40 nm) and nanoparticles (similar to 6 nm) were prepared, and their sensitivities to formaldehyde at room temperature were measured with and without the UV light irradiation (the intensity of light is 0.155 mW/cm(2)). The XRD, TEM and SEM were utilized to examine the size of crystal and the morphology of material. The transient photovoltage and photoluminescence spectra were utilized to investigate the photoelectric properties of ZnO. The ZnO nanorods with diameter of similar to 40 nm own the highest response to formaldehyde with the UV light illumination than that of other samples. It is attributed to the large surface-to-volume ratio and high photo-generated charge efficiency, which are two key parameters to determine the gas response. The transient photovoltage results further demonstrate that the photo-generated charge efficiency of gas sensing element decreases as the surface-to-volume ratio increases (i.e. the size of crystal decreases). Therefore, the particles with highest sensitivity are of a certain size, neither the largest nor the smallest tested. Our work may supply a direction to fabricate the high performance gas sensor with UV light illumination. (C) 2010 Elsevier B.V. All rights reserved.
摘要：
Persulfate is the latest oxidant which is being used increasingly for the remediation of groundwater and soil contaminated with organic compounds. It is of great significant to offer readers a general summary about different methods of activating persulfate, mainly including heat-activated, metal ions-activated, UV-activated, and alkaline-activated. Meanwhile, in addition to persulfate concentration as an influencing factor for persulfate oxidation process, selected information like temperature, anions, cations, pH, and humic acid are presented and discussed. The last section focuses on the advantages of different activated persulfate processes, and the suggestions and research needs for persulfate-based advanced oxidation in the remediation of polluted groundwater and soil.
关键词：
Heavy metal;Microbial community;Microbiological indicator;Soil diagnosis
摘要：
Heavy metal contamination of soil has become a serious global issue because of their persistence in the environment and the non-biodegradable nature leading to their accumulation to toxic levels. In order to achieve early warning and prevent soil quality from deteriorating, it is necessary to select suitable indices to diagnose heavy metal pollution. Microbiological indices for monitoring soil pollution by heavy metals are gaining attention. However, the related researches are scattered, and critical review is imperative. This review is mainly to provide readers with an in-depth understanding of the merits and limitations of microbiological indices for heavy metals contaminated and remediated soils. Microbiological indicators include microbial abundance, community diversity and structure, functional activity. The changes of different microbiological indices and the mechanism of microbial response to heavy metal stress in soils are comprehensively summarized. Furthermore, research gaps and future directions of the microbial ecotoxicological diagnosis of soil contamination by heavy metals are also proposed and discussed.
摘要：
A novel ultrathin Bi2WO6 nanosheets loaded g-C3N4 quantum dots (CNQDs/BWO) photocatalyst was successfully fabricated, and used to catalyze two representative organic pollutants, rhodamine B (RhB) and tetracycline (TC) under wide spectrum light irradiation. The degradation experiments showed that CNQDs/BWO exhibited enhanced photocatalytic activities towards degradation of organic pollutants. Under visible light irradiation, the 5% CNQDs/BWO exhibited the best degradation efficiency with 87% and 92.51% removal of TC and RhB within 60 min, respectively. And under near-infrared (NIR) light, the 5% CNQDs/BWO still showed the best performance, its degradation efficiency to TC were similar to 2 times than pure BWO. The upconversion behaviors of CNQDs might contribute to the enhanced photocatalysis. According to similar degradation trend, it is inferred that the catalytic mechanism in NIR light is consistent with that in visible light. The enhanced photocatalytic activity of CNQDs/BWO under wide spectrum light irradiation can be ascribed to a Z-scheme mechanism based on the calculated the lowest unoccupied molecular orbital (LUMO) of CNQDs and CB position of BWO, the free radical quenching experiment, and ESR characterization results. The composites have prominent light absorption, high stability and excellent photocatalysis efficiency, which would be used as a promising strategy for organic pollutants degradation. (C) 2019 Elsevier Inc. All rights reserved.
作者机构：
[Liu, Canjun; Li, Wenzhang; Li, Jie; Chen, Qiyuan] Cent S Univ, Sch Chem & Chem Engn, Changsha 410083, Peoples R China.;[Yang, Yahui] Hunan Agr Univ, Coll Resources & Environm, Changsha 410128, Hunan, Peoples R China.;[Li, Yaomin] UCL, Dept Chem, 20 Gordon St, London WC1H 0AJ, England.
通讯机构：
[Li, WZ; Li, J ] Cent S Univ, Sch Chem & Chem Engn, Changsha 410083, Peoples R China.;Cent S Univ, Sch Chem & Chem Engn, Changsha 410083, Peoples R China.
摘要：
In this study, Bi2S3 sensitive layer has been grown on the surface of WO3 nanoplate arrays via an in situ approach. The characterization of samples were carried out using scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and ultraviolet–visible absorption spectroscopy (UV-vis). The results show that the Bi2S3 layer is uniformly formed on the surface of WO3 nanoplates and less interfacial defects were observed in the interface between the Bi2S3 and WO3. More importantly, the Bi2S3/WO3 films as photoanodes for photoelectrochemical (PEC) cells display the enhanced PEC performance compared with the Bi2S3/WO3 films prepared by a sequential ionic layer adsorption reaction (SILAR) method. In order to understand the reason for the enhanced PEC properties, the electron transport properties of the photoelectrodes were studied by using the transient photocurrent spectroscopy and intensity modulated photocurrent spectroscopy (IMPS). The Bi2S3/WO3 films prepared via an in situ approach have a greater transient time constant and higher electron transit rate. This is most likely due to less interfacial defects for the Bi2S3/WO3 films prepared via an in situ approach, resulting in a lower resistance and faster carrier transport in the interface between WO3 and Bi2S3.
作者：
Norton, Gareth J.*;Williams, Paul N.;Adomako, Eureka E.;Price, Adam H.;Zhu, Yongguan;Zhao, Fang-Jie;McGrath, Steve;Deacon, Claire M.;Villada, Antia;Sommella, Alessia;Lu, Ying;Ming, Lei;De Silva, P. Mangala C. S.;Brammer, Hugh;Dasgupta, Tapash;Islam, M. Rafiqul;Meharg, Andrew A.
期刊：
Science of the Total Environment,2014年485-486(1):428-434 ISSN：0048-9697
摘要：
In a large scale survey of rice grains from markets (13 countries) and fields (6 countries), a total of 1578 rice grain samples were analysed for lead. From the market collected samples, only 0.6% of the samples exceeded the Chinese and EU limit of 0.2 mu g g(-1) lead in rice (when excluding samples collected from known contaminated/mine impacted regions). When evaluating the rice grain samples against the Food and Drug Administration's (FDA) provisional total tolerable intake (PTTI) values for children and pregnant women, it was found that only people consuming large quantities of rice were at risk of exceeding the MI from rice alone. Furthermore, 6 field experiments were conducted to evaluate the proportion of the variation in lead concentration in rice grains due to genetics. A total of 4 of the 6 field experiments had significant differences between genotypes, but when the genotypes common across all six field sites were assessed, only 4% of the variation was explained by genotype, with 9.5% and 11% of the variation explained by the environment and genotype by environment interaction respectively. Further work is needed to identify the sources of lead contamination in rice, with detailed information obtained on the locations and environments where the rice is sampled, so that specific risk assessments can be performed. (C) 2014 Elsevier B.V. All rights reserved.
