المؤلفون: Zhen Zhang, Dawei Wu, Jing Liu, Yuchen Dong, Fenghua Shen

المصدر: Environmental Science & Technology. 53:1725-1731

مصطلحات موضوعية: Flue gas, Sorbent, Materials science, chemistry.chemical_element, General Chemistry, 010501 environmental sciences, Nonthermal plasma, 01 natural sciences, Mercury (element), Adsorption, Porous carbon, chemistry, Chemical engineering, Environmental Chemistry, Co doped, 0105 earth and related environmental sciences

الوصف: In this study, a novel Hg0 adsorption strategy based on nonthermal plasma and porous carbon was proposed and tested. The O2 and NO in flue gas were used to activate porous carbon with auxiliary pla...

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::cf4c1d59af01462d81d8854c2e4b5dafTest
https://doi.org/10.1021/acs.est.8b05777Test

المؤلفون: Jing Liu, Zhen Zhang, Sen Miao, Zhen Wang, Bingkai Zhang, Yingju Yang

المصدر: Environmental Science & Technology. 50:5398-5404

مصطلحات موضوعية: Reaction mechanism, Chemistry, Selective catalytic reduction, Mercury, 02 engineering and technology, General Chemistry, 010402 general chemistry, 021001 nanoscience & nanotechnology, Photochemistry, 01 natural sciences, Catalysis, Transition state, Dissociation (chemistry), 0104 chemical sciences, Coal, Adsorption, Physisorption, Catalytic oxidation, Environmental Chemistry, 0210 nano-technology, Oxidation-Reduction, Power Plants

الوصف: Catalytic oxidation of elemental mercury (Hg(0)) through a selective catalytic reduction (SCR) system is a promising method to reduce mercury emissions from coal-burning power plants. The density functional theory (DFT) and periodic slab models were used to study the reaction mechanism of Hg(0) oxidation by HBr on V2O5/TiO2 SCR catalyst surface. The interaction mechanisms of Hg(0), HBr, HgBr, and HgBr2 on V2O5/TiO2(001) were investigated. The oxidation reaction energy profiles and the corresponding geometries of the intermediates, final states, and transition states were researched. The results indicate that Hg(0) and HgBr2 are weakly adsorbed on the oxygen sites of the V2O5/TiO2(001) surface with physisorption. HgBr is chemically adsorbed on the surface. HBr is dissociatively adsorbed on the surface with an energy barrier of 85.59 kJ/mol. The reaction of Hg(0) oxidation by HBr follows the Eley-Rideal mechanism: Hg(0) interacts with a surface Br from HBr dissociation to form HgBr, and surface HgBr further interacts with HBr to form HgBr2, last HgBr2 desorbs from the surface. Comparing the energy pathway of Hg(0) oxidation over V2O5/TiO2(001) surface by HBr to that of HCl, it is found that the dissociation energy barrier of HBr is lower than that of HCl, the formation and desorption energy barriers of HgBr2 are also lower than that of HgCl2, which explains why HBr is much more effective than HCl in promoting Hg(0) oxidation.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::85cac5e30b49b2b3920a7ba1a609083fTest
https://doi.org/10.1021/acs.est.6b00549Test

المؤلفون: Fenghua Shen, Jing Liu, Zhen Zhang, Jinxin Dai

المصدر: Environmental Science & Technology. 49:13716-13723

مصطلحات موضوعية: Flue gas, Kinetics, chemistry.chemical_element, Coal combustion products, complex mixtures, Arsenic, otorhinolaryngologic diseases, Environmental Chemistry, Coal, Air Pollutants, integumentary system, business.industry, Spectrum Analysis, Temperature, technology, industry, and agriculture, General Chemistry, respiratory tract diseases, chemistry, Fluidized bed, Environmental chemistry, Gases, Inductively coupled plasma, business, Pyrolysis

الوصف: The kinetic behavior of arsenic (As) release during coal combustion and pyrolysis in a fluidized bed was investigated by applying an on-line analysis system of trace elements in flue gas. This system, based on inductively coupled plasma optical emission spectroscopy (ICP-OES), was developed to measure trace elements concentrations in flue gas quantitatively and continuously. Obvious variations of arsenic concentration in flue gas were observed during coal combustion and pyrolysis, indicating strong influences of atmosphere and temperature on arsenic release behavior. Kinetic laws governing the arsenic release during coal combustion and pyrolysis were determined based on the results of instantaneous arsenic concentration in flue gas. A second-order kinetic law was determined for arsenic release during coal combustion, and the arsenic release during coal pyrolysis followed a fourth-order kinetic law. The results showed that the arsenic release rate during coal pyrolysis was faster than that during coal combustion. Thermodynamic calculations were carried out to identify the forms of arsenic in vapor and solid phases during coal combustion and pyrolysis, respectively. Ca3(AsO4)2 and Ca(AsO2)2 are the possible species resulting from As-Ca interaction during coal combustion. Ca(AsO2)2 is the most probable species during coal pyrolysis.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::0dfb41d15125d0440a148849bfca5fdcTest
https://doi.org/10.1021/acs.est.5b03626Test

المؤلفون: Zhen Zhang, Guibin Jiang, Jingfu Liu, Bing Shao

المصدر: Environmental Science & Technology. 44:1030-1035

مصطلحات موضوعية: chemistry.chemical_classification, Detection limit, Sulfonamides, Time Factors, Chromatography, medicine.diagnostic_test, Sulfadimidine, Metal ions in aqueous solution, Fluoroimmunoassay, Antibodies, Monoclonal, Water, chemistry.chemical_element, General Chemistry, Sulfadiazine, Europium, chemistry, Immunoassay, medicine, Environmental Chemistry, Humic acid, Chelation, Water Pollutants, Chemical, Arsenic, Environmental Monitoring, medicine.drug

الوصف: Using monoclonal antibodies labeled with Eu(3+) chelates, time-resolved fluoroimmunoassay (TRFIA) methods were developed for the determination of trace sulfamethazine (SMZ), sulfa-methoxazole (SMX), and sulfadiazine (SDZ) in environmental waters. Under the optimized conditions, the developed methods offered (i) low detection limits (9.8 ng/L SMZ, 6.1 ng/L SMX, and 5.4 ng/L SDZ, based on 90% inhibition) which were about 1 order of magnitude lower than that of the enzyme-linked immunosorbent assay (ELISA), (ii) high selectivity with no cross-reactivity (0.05%) to similarly structured sulfonamides; (iii) high tolerance to variation of the sample pH (6.0-9.0) and salinity (0-100 mM), as well as the presence of humic acid (0-100 mg/L DOC) and heavy metals (0-1 mg/L concentration each of Cu(2+), Cd(2+), Hg(2+), Pb(2+), and As(V)) in the samples, and (iv) direct determination with low cost, high sample throughput, and low sample consumption (50-100 microL). The proposed TRFIA procedures were applied to determine sulfonamides in a variety of surface water and wastewater samples without sample pretreatment other than filtration. The satisfactory recoveries (64-127%) and reproducibilities (CV = 0.2-16%) achieved, as well as the good agreement with those given by liquid chromatography-tandem mass spectroscopy and ELISA methods, demonstrated the applicability of the proposed TRFIA methods for routine screening/quantification of sulfonamides in environmental waters.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::a3b8222ea1b7947a95d7bddc22340018Test
https://doi.org/10.1021/es903328bTest

المؤلفون: Zhen Wang, Jing Liu, Bingkai Zhang, Yingju Yang, Zhen Zhang, Sen Miao

المصدر: Environmental Science & Technology; 5/17/2016, Vol. 50 Issue 10, p5398-5404, 7p

المؤلفون: Zhen Zhang^1,2, Jing-fu Liu¹ jfliu@rcees.ac.cn, Ting-ting Feng³, Yan Yao³, Li-hong Gao¹, Gui-bin Jiang¹

المصدر: Environmental Science & Technology. 1/1/2013, Vol. 47 Issue 1, p454-462. 9p.

مصطلحات موضوعية: FLUOROIMMUNOASSAY, FLUOROQUINOLONES, ENVIRONMENTAL risk assessment, WATER pollution measurement, MONOCLONAL antibodies, TIME-resolved measurements, CIPROFLOXACIN, WATER pollution

مستخلص: Due to the widespread occurrence in the environment and potential risk toward organisms of fluoroquinolones (FQs), it is of importance to develop high efficient methods for assessing their occurrence and environmental risk. A monoclonal antibody (Mab) with broad cross-reactivity to FQs was produced by immunizing BALB/c mice with a synthesized immunogen prepared by conjugating ciprofloxacin with bovine serum albumin. This developed Mab (C2F3C2) showed broad and high cross-reactivity (40.3– 116%) to 12 out of the 13 studied FQs. Using this Mab and norfloxacin conjugated with carrier protein ovalbumin as coating antigen, a time- resolved fluoroimmunoassay (TRFIA) method was developed for determining the total concentration of at least 12 FQs in environmental waters. The respective detection limit (LOD) and IC50 calculated from the standard curve were 0.053 μg/L and 1.83 μg/L for enrofloxacin (ENR). The LODs of the other FQs, estimated based on the corresponding cross- reactivity and the LOD of ENR, were in the range of 0.051–0.10 μg/L. The developed TRFIA method showed good tolerance to various interfering substances present in environmental matrix at relevant levels, such as humic acids (0–10 mg/L DOC), water hardness (0–2% Ca2+ and Mg2+, w/v), and heavy metals (0–1 mg/L). The spiked recoveries estimated by spiking 0.5, 1, and 2 μg/L of five representative FQs into various water samples including paddy water, tap water, pond water, and river water were in the range of 63–120%. The measured total FQ concentration by TRFIA agreed well with that of liquid chromatography–tandem mass spectrometry and was applied to directly evaluate the occurrence and environmental risk of FQs in the surface water of a case area. TRFIA showed high efficiency and great potential in environmental risk assessment as it measures directly the total concentration of a class of pollutants. [ABSTRACT FROM AUTHOR]

: Copyright of Environmental Science & Technology is the property of American Chemical Society and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

المؤلفون: Zhen Zhang^1,2, Jing-fu Liu¹ jfliu@rcees.ac.cn, Xiao-qiang Cai¹, Wei-wei Jiang³, Wen-ru Luo¹, Gui-bin Jiang¹

المصدر: Environmental Science & Technology. 2/15/2011, Vol. 45 Issue 4, p1688-1694. 7p.

مصطلحات موضوعية: TOXICOLOGICAL chemistry, CHEMISTRY experiments, TOXICITY testing, ADDITION reactions, DISSOLVED organic matter, IONIC liquids, HUMIC acid, CHEMICAL reduction, BIOAVAILABILITY, IMIDAZOLES

مستخلص: Two typical ionic liquids (ILs), 1-butyl-3-methylimidazolium chloride ([C4MIM]Cl) and 1-octyl-3-methylimidazolium chloride ([C8MIM]Cl), are demonstrated to associate strongly with dissolved organic matter (DOM) with distribution coefficients (KDOC) in the range of 104.2 to 104.6 for Aldrich humic acid (used as model DOM). With the increase of humic acid concentration to 11 μg/mL DOC (dissolved organic carbon), the free fraction (ratio of freely dissolved to total concentration) of [C4MIM]Cl and [C8MIM]Cl reduced to about 0.85 and 0.79, respectively. This reduction of freely dissolved concentration gave rise to remarkable reduction of bioavailability and toxicity of the two ILs. MTT assay with HepG2 cell lines showed that the EC50 values were 459 μmol/L for [C4MIM]Cl and 12 μmol/L for [C8MIM]Cl, respectively, and the cell viability increased about 50% in the presence of trace amount of humic acid (1 μg/mL DOC). The SOS/umu test indicated mutagenicity for [C4MIM]Cl at levels above 664 μmol/L, and the genotoxicity was diminished with the addition of trace humic acid (0.00000374-0.374 μg/mL DOC). The studied ILs showed acute toxicity toward model fish medaka with a 96 h median lethal concentration (LC50) of 2254 μmol/L for [C4MIM]Cl and 366 μmol/L for [C8MIM]Cl. The addition of humic acid (5.49 μg/mL DOC for [C8MIM]Cl, 1.37 μg/mL DOC for [C4MIM]Cl) to IL solutions reduced the death rate of medaka to a minimum value of 25% of that at zero DOC. Our results suggest that DOM may play an important role in determining the environmental fate and toxicity of imidazolium-based ILs, and its effects should be taken into account in assessing the environmental risk of ILs. [ABSTRACT FROM AUTHOR]

: Copyright of Environmental Science & Technology is the property of American Chemical Society and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

المؤلفون: ZHEN ZHANG¹, JING-FU LIU¹ jfliu@rcees.ac.cn, BING SHAO², GUI-BIN JIANG¹

المصدر: Environmental Science & Technology. 2/1/2010, Vol. 44 Issue 3, p1030-1035. 6p.

مصطلحات موضوعية: ENVIRONMENTAL forensics, WATER analysis, SULFAMETHAZINE, SULFAMETHOXAZOLE, SULFADIAZINE, WATER sampling, RUNOFF, SEWAGE, ENZYME-linked immunosorbent assay, LIQUID chromatography, TANDEM mass spectrometry

مستخلص: Using monoclonal antibodies labeled with Eu3+ chelates, time-resolved fluoroimmunoassay (TRFIA) methods were developed for the determination of trace sulfamethazine (SMZ), sulfa-methoxazole (SMX), and sulfadiazine (SDZ) in environmental waters. Under the optimized conditions, the developed methods offered (i) low detection limits (9.8 ng/L SMZ, 6.1 ng/L SMX, and 5.4 ng/L SDZ, based on 90% inhibition) which were about 1 order of magnitude lower than that of the enzyme-linked immunosorbent assay (ELISA), (ii) high selectivity with no cross-reactivity (<0.05%) to similarly structured sulfonamides; (iii) high tolerance to variation of the sample pH (6.0-9.0) and salinity (0-100 mM), as well as the presence of humic acid (0-100 mg/L DOC) and heavy metals (0-1 mg/L concentration each of Cu2+, Cd2+, Hg2+, Pb2+ and As(V)) in the samples, and (iv) direct determination with low cost, high sample throughput, and low sample consumption (50-100 μL). The proposed TRFIA procedures were applied to determine sulfonamides in a variety of surface water and wastewater samples without sample pretreatment other than filtration. The satisfactory recoveries (64-127%) and reproducibilities (CV = 0.2-16%) achieved, as well as the good agreement with those given by liquid chromatography—tandem mass spectroscopy and ELISA methods, demonstrated the applicability of the proposed TRFIA methods for routine screening/quantification of sulfonamides in environmental waters. [ABSTRACT FROM AUTHOR]

: Copyright of Environmental Science & Technology is the property of American Chemical Society and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

المؤلفون: JING-SHENG LI, XIAO-XIA LI, QIN SHEN, ZHI-ZHEN ZHANG, FEI-HU DU

المصدر: Environmental Science & Technology; 10/1/2010, Vol. 44 Issue 19, p7673-7677, 5p