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Decontamination of Cr(VI) facilitated formation of persistent free radicals on rice husk derived biochar

Kaikai Zhang, Peng Sun, Yanrong Zhang

《环境科学与工程前沿（英文）》 2019年 第13卷 第2期 doi: 10.1007/s11783-019-1106-7

摘要：

PFRs were produced on biochar during Cr(VI) decontamination.

PFRs formation on biochar was owing to the oxidization of phenolic-OH by Cr(VI).

Appearance of excessive oxidant led to the consumption of PFRs on biochar.

Biochar charred at high temperature possessed great performance to Cr(VI) removal.

关键词： Biochar     Persistent free radicals     Phenolic hydroxyl groups     Cr(VI) reduction    

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Light-induced variation in environmentally persistent free radicals and the generation of reactive radical

Yafang Shi, Yunchao Dai, Ziwen Liu, Xiaofeng Nie, Song Zhao, Chi Zhang, Hanzhong Jia

《环境科学与工程前沿（英文）》 2020年 第14卷 第6期 doi: 10.1007/s11783-020-1285-2

摘要： Abstract • Light irradiation increased the concentration of free radicals on HS. • The increased spin densities on HS readily returned back to the original value. • The “unstable” free radicals induced the formation of reactive radical species. • Reactive radicals’ concentration correlated strongly with EPFRs’ concentration. Environmentally persistent free radicals (EPFRs) in humic substances play an essential role in soil geochemical processes. Light is known to induce EPFRs formation for dissolved organic matter in aquatic environments; however, the impacts of light irradiation on the variation of EPFRs in soil humic substances remain unclear. In this study, humic acid, fulvic acid, and humin were extracted from peat soil and then in situ irradiated using simulated sunlight. Electron paramagnetic resonance spectroscopy results showed that with the increasing irradiation time, the spin densities and g-factors of humic substances rapidly increased during the initial 20 min and then gradually reached a plateau. After irradiation for 2h, the maximum spin density levels were up to 1.63 × 1017, 2.06 × 1017, and 1.77 × 1017 spins/g for the humic acid, fulvic acid, and humin, respectively. And the superoxide radicals increased to 1.05 × 1014–1.46 × 1014 spins/g while the alkyl radicals increased to 0.47 × 1014–1.76 × 1014 spins/g. The light-induced EPFRs were relatively unstable and readily returned back to their original state under dark and oxic conditions. Significant positive correlations were observed between the concentrations of EPFRs and reactive radical species (R2 = 0.65–0.98, p<0.05), which suggested that the newly produced EPFRs contributed to the formation of reactive radical species. Our findings indicate that under the irradiation humic substances are likely to be more toxic and reactive in soil due to the formation of EPFRs.

关键词： Peat     Humic substances     Environmentally persistent free radicals     Light irradiation     Reactive radical species    

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Persistent free radicals in humin under redox conditions and their impact in transforming polycyclic

Hanzhong Jia, Yafang Shi, Xiaofeng Nie, Song Zhao, Tiecheng Wang, Virender K. Sharma

《环境科学与工程前沿（英文）》 2020年 第14卷 第4期 doi: 10.1007/s11783-020-1252-y

摘要： Abstract • Regulation of redox conditions promotes the generation of free radicals on HM. • HM-PFRs can be fractionated into active and inactive types depending on stability. • The newly produced PFRs readily release electrons to oxygen and generate ROS. • PFR-induced ROS mediate the transformation of organic contaminants adsorbed on HM. The role of humic substance-associated persistent free radicals (PFRs) in the fate of organic contaminants under various redox conditions remains unknown. This study examined the characterization of original metal-free peat humin (HM), and HM treated with varying concentrations of H2O2 and L-ascorbic acid (VC) (assigned as H2O2-HM and VC-HM). The concentration of PFRs in HM increased with the addition of VC/H2O2 at concentrations less than 0.08 M. The evolution of PFRs in HM under different environmental conditions (e.g., oxic/anoxic and humidity) was investigated. Two types of PFRs were detected in HM: a relatively stable radical existed in the original sample, and the other type, which was generated by redox treatments, was relatively unstable. The spin densities of VC/H2O2-HM readily returned to the original value under relatively high humidity and oxic conditions. During this process, the HM-associated “unstable” free radicals released an electron to O2, inducing the formation of reactive oxygen species (ROS, i.e., •OH and •O2−). The generated ROS promoted the degradation of polycyclic aromatic hydrocarbons based on the radical quenching measurements. The transformation rates followed the order naphthalene>phenanthrene>anthracene>benzo[a]pyrene. Our results provide valuable insight into the HM-induced transformation of organic contaminants under natural conditions.

关键词： Humic substance     Polycyclic aromatic hydrocarbons (PAHs)     Persistent free radicals (PFRs)     Redox     Reactive oxygen species (ROS)    

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NADPH oxidase and reactive oxygen species as signaling molecules in carcinogenesis

Gang WANG

《医学前沿（英文）》 2009年 第3卷 第1期   页码 1-7 doi: 10.1007/s11684-009-0018-5

摘要： Reactive oxygen species (ROS) are small molecule metabolites of oxygen that are prone to participate in redox reactions their high reactivity. Intracellular ROS could be generated in reduced nicotinamide-adenine dinucleotidephosphate (NADPH) oxidase-dependent and/or NADPH oxidase-independent manners. Physiologically, ROS are involved in many signaling cascades that contribute to normal processes. One classical example is that ROS derived from the NADPH oxidase and released in neurotrophils are able to digest invading bacteria. Excessive ROS, however, contribute to pathogenesis of various human diseases including cancer, aging, dimentia and hypertension. As signaling messengers, ROS are able to oxidize many targets such as DNA, proteins and lipids, which may be linked with tumor growth, invasion or metastasis. The present review summarizes recent advances in our comprehensive understanding of ROS-linked signaling pathways in regulation of tumor growth, invasion and metastasis, and focuses on the role of the NADPH oxidase-derived ROS in cancer pathogenesis.

关键词： free radicals     tumor     phox     cell proliferation     cancer therapy    

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One-pot hydrothermal fabrication of BiVO/FeO/rGO composite photocatalyst for the simulated solar light-driven degradation of Rhodamine B

《环境科学与工程前沿（英文）》 2022年 第16卷 第3期 doi: 10.1007/s11783-021-1470-y

摘要：

• BiVO4/Fe3O4/rGO has excellent photocatalytic activity under solar light radiation.

关键词： Photocatalysis     Ternary magnetic photocatalyst     Visible-light-driven     Free radicals trapping     Reusability     Recycling    

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Predictive models on photolysis and photoinduced toxicity of persistent organic chemicals

Qing ZHANG

《环境科学与工程前沿（英文）》 2013年 第7卷 第6期   页码 803-814 doi: 10.1007/s11783-013-0547-7

摘要： Photodegradation is a major abiotic transformation pathway of toxic chemicals in the environment, which in some cases might lead to photoinduced toxicities. The data on photodegradation kinetics and photoinduced toxicities of organic chemicals are essential for their risk assessment. However, the relevant data are only available for a limited number of chemicals, due to the difficulty and high cost of experimental determination. Quantitative structure-activity relationship (QSAR) models that relate photodegradation kinetics or photoinduced toxicity of organic chemicals with their physicochemical properties or molecular structural descriptors may enable simple and fast estimation of their photochemical behaviors. This paper reviews the QSAR models on photodegradation quantum yields and rate constants for toxic organic chemicals in different media including liquid phase, gaseous phase, surfaces of plant leaves, and QSAR models on photoinduced toxicity of organic chemicals to plants, bacteria, and aquatic invertebrates. Further prospects for QSAR model development on photodegradation kinetics and photoinduced toxicity of refractory organic chemicals are proposed.

关键词： quantitative structure-activity relationship (QSAR) models     photodegradation     persistent organic pollutants     environmental media     mechanisms    

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Characterization of bacterial communities during persistent fog and haze events in the Qingdao coastal

《环境科学与工程前沿（英文）》 2021年 第15卷 第3期 doi: 10.1007/s11783-020-1334-x

摘要：

• Light haze had little effect on bacterial communities.

关键词： Bacterial community     Persistent fog and haze     Particle size    

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Addressing the environmental risk of persistent organic pollutants in China

Bin WANG, Jun HUANG, Shubo DENG, Xiaoling YANG, Gang YU

《环境科学与工程前沿（英文）》 2012年 第6卷 第1期   页码 2-16 doi: 10.1007/s11783-011-0370-y

摘要： The Stockholm Convention on persistent organic pollutants (POPs) was adopted in 2001. This year is the 10th anniversary of the adoption of the Convention. Until now, 22 chemicals or chemical categories have been listed as POPs in the Stockholm Convention. The POPs Research Center was established in Tsinghua University in the same year when the Convention was adopted. In the last ten years, much work has been done by Chinese researchers to understand the environmental risk of POPs in China. This article aims to review the recent research progress of our POPs Research Center and some other Chinese researchers’ studies in addressing the environmental risk of POPs, including the priority screening and inventory study of POPs, monitoring and modeling of POPs pollution and exposure, and environmental risk assessment and modeling of POPs. Although great advances in addressing the environmental risk of POPs have been made in recent years, we are still facing quite a few problems, such as data scarcity and uncertainty in environmental risk assessment of POPs. The study on the effect of POPs mixtures is in its infancy and currently POPs are usually assessed from legal perspective by risk assessment of single chemicals. These problems should be well addressed by further efforts. Further studies should also be taken in future to study environment risk of POPs by considering aspects of coupled dynamics between climate processes and POPs. Such sound scientific, risk-based information can support decision-making aiming to effectively minimize the risk level of POPs.

关键词： persistent organic pollutant (POPs)     environmental risk assessment     inventory     environmental monitoring     fugacity model     emerging POPs    

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Kinetics and mechanism of nitrobenzene degradation by hydroxyl radicals-based ozonation process enhanced

Weizhou Jiao, Shengjuan Shao, Peizhen Yang, Kechang Gao, Youzhi Liu

《化学科学与工程前沿（英文）》 2021年 第15卷 第5期   页码 1197-1205 doi: 10.1007/s11705-020-1998-6

摘要： This study investigated the indirect oxidation of nitrobenzene (NB) by hydroxyl radicals (·OH) in a rotating packed bed (RPB) using competitive kinetics method with -nitrochlorobenzene as a reference compound. The rate constants of NB with ·OH are calculated to be between (1.465±0.113) × 10 L/(mol·s) and (2.497±0.192) × 10 L/(mol·s). The experimental data are fitted by the modified Arrhenius equation, where the activation energy is 4877.74 J/mol, the order of NB concentration, rotation speed, and initial pH is 0.2425, 0.1400 and 0.0167, respectively. The ozonation process of NB could be enhanced by RPB, which is especially effective for highly concentrated NB-containing wastewater under alkaline conditions. The high gravity technology can accelerate ozone mass transfer and self-decomposition of ozone to produce more ·OH, resulting in an increase in the indirect oxidation rate of NB by ·OH and consequently effective degradation of NB in wastewater.

关键词： high gravity technology     hydroxyl radicals     nitrobenzene     reaction kinetics    

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Enhanced degradation of trichloroethene by calcium peroxide activated with Fe(III) in the presence of citric acid

Xiang ZHANG,Xiaogang GU,Shuguang LU,Zhouwei MIAO,Minhui XU,Xiaori FU,Muhammad DANISH,Mark L. BRUSSEAU,Zhaofu QIU,Qian SUI

《环境科学与工程前沿（英文）》 2016年 第10卷 第3期   页码 502-512 doi: 10.1007/s11783-016-0838-x

摘要： Trichloroethene (TCE) degradation by Fe(III)-activated calcium peroxide (CP) in the presence of citric acid (CA) in aqueous solution was investigated. The results demonstrated that the presence of CA enhanced TCE degradation significantly by increasing the concentration of soluble Fe(III) and promoting H O generation. The generation of HO? and O ? in both the CP/Fe(III) and CP/Fe(III)/CA systems was confirmed with chemical probes. The results of radical scavenging tests showed that TCE degradation was due predominantly to direct oxidation by HO?, while O ? strengthened the generation of HO? by promoting Fe(III) transformation in the CP/Fe(III)/CA system. Acidic pH conditions were favorable for TCE degradation, and the TCE degradation rate decreased with increasing pH. The presence of Cl , HCO , and humic acid (HA) inhibited TCE degradation to different extents for the CP/Fe(III)/CA system. Analysis of Cl production suggested that TCE degradation in the CP/Fe(III)/CA system occurred through a dechlorination process. In summary, this study provided detailed information for the application of CA-enhanced Fe(III)-activated calcium peroxide for treating TCE contaminated groundwater.

关键词： calcium peroxide     trichloroethene (TCE)     citric acid     ferric ion     free radicals     oxidation    

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Regulation of radicals by hydrogen-donor solvent in direct coal liquefaction

《化学科学与工程前沿（英文）》 2022年 第16卷 第12期   页码 1689-1699 doi: 10.1007/s11705-022-2186-7

摘要： Radicals are important intermediates in direct coal liquefaction. Certain radicals can cause the cleavage of chemical bonds. At high temperatures, radical fragments can be produced by the splitting of large organic molecules, which can break strong chemical bonds through the induction pyrolysis of radicals. The reaction between the formation and annihilation of coal radical fragments and the effect of hydrogen-donor solvents on the radical fragments are discussed in lignite hydrogenolysis. Using the hydroxyl and ether bonds as indicators, the effects of different radicals on the cleavage of chemical bond were investigated employing density functional theory calculations and lignite hydrogenolysis experiments. Results showed that the adjustment of the coal radical fragments could be made by the addition of hydrogen-donor solvents. Results showed that the transition from coal radical fragment to H radical leads to the variation of product distribution. The synergistic mechanism of hydrogen supply and hydrogenolysis of hydrogen-donor solvent was proposed.

关键词： direct coal liquefaction     hydrogen-donor solvent     induced pyrolysis     radical mechanism     density functional theory calculations    

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美国NRC颠覆性技术持续预测系统浅析

张晓林

《中国工程科学》 2018年 第20卷 第6期   页码 117-121 doi: 10.15302/J-SSCAE-2018.06.019

摘要：

美国国家研究委员会（NRC）发布的《颠覆性技术持续性预测》（Persistent Forecasting of Disruptive Technologies

关键词： 颠覆性技术     持续预测     理想系统    

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Perfluoroalkane acids in human milk under the global monitoring plan of the Stockholm Convention on Persistent

《环境科学与工程前沿（英文）》 2022年 第16卷 第10期 doi: 10.1007/s11783-022-1541-8

摘要：

● Perfluorooctanesulfonic acid and perfluorooctanoic acid highest in human milk.

关键词： Human biomonitoring     Human breast milk     LC-MS/MS analysis     Lifestyle parameters    

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Endosulfan in the Chinese environment: monitoring and modeling

Hongliang JIA, Liyan LIU, Yeqing SUN, Daoji CAI, Jianxin HU, Nanqi REN, Yifan LI

《环境科学与工程前沿（英文）》 2012年 第6卷 第1期   页码 32-44 doi: 10.1007/s11783-011-0375-6

摘要： This paper reviews the usage and emissions of endosulfan, the newest member of the persistent organic pollutants (POPs), in China, and its fate and behavior in Chinese environment. Endosulfan usage in China has been estimated to be approximately 25700 t between 1994 and 2004. Concentrations of endosulfan in different environmental compartments in China, such as air, soil, water, and biota, but focusing at air and surface soil, have been summarized. Concentrations of total endosulfan in surface soil across China were ranged from below detection limit (BDL) to 19000 pg·g dry weight (dw), with geometric mean of 120 pg·g dw. The results indicated that endosulfan sulfate had highest concentration in Chinese soil, followed by - and -endosulfan. Air concentrations of endosulfan in China were ranged 0–340 pg·m for -endosulfan and 0–121 pg·m for -endosulfan, with high concentrations occurred in the cotton production areas. Gridded usage inventories of endosulfan on a fine gridded system with a 1/4° longitude by 1/6° latitude resolution were compiled, from which, emission to air and residues in soil of endosulfan were calculated in each grid by using a modified simplified gridded pesticide emission and residue model (SGPERM), an integrated modeling system combining mathematical model, database management system, and geographic information system. Total emissions were around 10800 t from 1994 to 2004. Based on the emission and residue inventories, concentrations of - and -endosulfan in Chinese air and agricultural surface soil were also calculated for each grid cell, which are in general consistent with the published monitoring data.

关键词： endosulfan     monitoring     modeling     inventories     persistent organic pollutants     persistent organic pollutants (POPs)    

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combination with determination of bilirubin from duodenal drainage in differential diagnosis of infantile persistent

Sheng-Xuan LIU, Zhi-Hua HUANG

《医学前沿（英文）》 2010年 第4卷 第3期   页码 342-345 doi: 10.1007/s11684-010-0099-1

摘要： The aim of this study was to investigate the value of technetium etifenin injection ( Tc-EHIDA) hepatobiliary scintigraphy in combination with determination of bilirubin from duodenal drainage in differential diagnosis between infantile hepatitis syndrome and biliary atresia. Tc-EHIDA hepatobiliary scintigraphy in combination with duodenal fluid examination was used for evaluation in 84 infants with persistent infantile jaundice. For diagnosing biliary atresia, the sensitivity and specificity of scintigraphy were 100% and 74.5%, respectively; the sensitivity and specificity of scintigraphy in combination with duodenal fluid examination were 100% and 100%, respectively. In conclusion, hepatobiliary scintigraphy, which is a noninvasive, safe, valuable examination method, in combination with examination of duodenal fluid, is of value for the differential diagnosis between infantile hepatitis syndrome and biliary atresia.

关键词： jaundice     radionuclide hepatobiliary scintigraphy     duodenal drainage    

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标题 作者 时间 类型 操作

Decontamination of Cr(VI) facilitated formation of persistent free radicals on rice husk derived biochar

Kaikai Zhang, Peng Sun, Yanrong Zhang

期刊论文

Light-induced variation in environmentally persistent free radicals and the generation of reactive radical

Yafang Shi, Yunchao Dai, Ziwen Liu, Xiaofeng Nie, Song Zhao, Chi Zhang, Hanzhong Jia

期刊论文

Persistent free radicals in humin under redox conditions and their impact in transforming polycyclic

Hanzhong Jia, Yafang Shi, Xiaofeng Nie, Song Zhao, Tiecheng Wang, Virender K. Sharma

期刊论文

NADPH oxidase and reactive oxygen species as signaling molecules in carcinogenesis

Gang WANG

期刊论文

One-pot hydrothermal fabrication of BiVO/FeO/rGO composite photocatalyst for the simulated solar light-driven degradation of Rhodamine B

期刊论文

Predictive models on photolysis and photoinduced toxicity of persistent organic chemicals

Qing ZHANG

期刊论文

Characterization of bacterial communities during persistent fog and haze events in the Qingdao coastal

期刊论文

Addressing the environmental risk of persistent organic pollutants in China

Bin WANG, Jun HUANG, Shubo DENG, Xiaoling YANG, Gang YU

期刊论文

Kinetics and mechanism of nitrobenzene degradation by hydroxyl radicals-based ozonation process enhanced

Weizhou Jiao, Shengjuan Shao, Peizhen Yang, Kechang Gao, Youzhi Liu

期刊论文

Enhanced degradation of trichloroethene by calcium peroxide activated with Fe(III) in the presence of citric acid

Xiang ZHANG,Xiaogang GU,Shuguang LU,Zhouwei MIAO,Minhui XU,Xiaori FU,Muhammad DANISH,Mark L. BRUSSEAU,Zhaofu QIU,Qian SUI

期刊论文

Regulation of radicals by hydrogen-donor solvent in direct coal liquefaction

期刊论文

美国NRC颠覆性技术持续预测系统浅析

张晓林

期刊论文

Perfluoroalkane acids in human milk under the global monitoring plan of the Stockholm Convention on Persistent

期刊论文

Endosulfan in the Chinese environment: monitoring and modeling

Hongliang JIA, Liyan LIU, Yeqing SUN, Daoji CAI, Jianxin HU, Nanqi REN, Yifan LI

期刊论文

combination with determination of bilirubin from duodenal drainage in differential diagnosis of infantile persistent

Sheng-Xuan LIU, Zhi-Hua HUANG

期刊论文