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hydroxyl radical production by abiotic oxidation of pyrite under estuarine conditions:The effects of aging,seawater anions and illumination

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Journal of Environmental Sciences 2024年第1期135卷 715-727页

作者： Ruixue Liu Yinshun Dai Yucheng Feng Shiwen Sun Xiaodong Zhang Chunjiang An Shan Zhao Shandong Key Laboratory of Water Pollution Control and Resource Reuse School of Environmental Science and EngineeringShandong UniversityQingdao 266237China Department of Building Civil and Environmental EngineeringConcordia UniversityMontrealQC H3G 1M8Canada

Pyrite is widely distributed in estuarine sediments as an inexpensive natural Fenton-like reagent,however,the mechanism on the hydroxyl radical(HO^(·))production by pyrite under estuarine environmental conditions is still poorly *** batch experiments were performed to investigate the effects of estuarine conditions including aging(in air,in water),seawater anions(Cl^(-),Br^(-)and HCO_(3)^(-))and light on the HO^(·)production by pyrite *** one-electron transfer dominated the process from O_(2) to HO^(·)induced by oxidation of *** Fe(oxyhydr)oxide coatings on the surface of pyrite aged in air and water consumed hydrogen peroxide while mediating the electron transfer,and the combined effect of the two resulted in a suppression of HO^(·)production in the early stage of aging and a promotion of HO^(·)production in the later stage of *** of the surface oxide layers by aggressive anions was the main reason for the inhibition of HO^(·)production by Cl^(-)and Br^(-),and the generation of Cl^(·)and Br^(·)may also play a role in the scavenging of HO^(·).HCO_(3)^(-)increased the average rate of HO^(·)production through surface-CO_(2) complexes formed by adsorption on the surface of *** significant enhancement of HO^(·)production under light was attributed to the formation of photoelectrons induced by photochemical reactions on pyrite and its surface oxide *** findings provide new insights into the environmental chemical behavior of pyrite in the estuary and enrich the understanding of natural remediation of estuarine environments.

关键词： hydroxyl radical Pyrite oxidation Aging Anions Irradiation

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hydroxyl radical-involved cancer therapy via Fenton reactions

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Frontiers of Chemical Science and Engineering 2022年第3期16卷 345-363页

作者： Mengying Liu Yun Xu Yanjun Zhao Zheng Wang Dunyun Shi School of Pharmaceutical Science&Technology Tianjin UniversityTianjin300072China Central Lab Shenzhen Second People’s Hospital/the First Affiliated Hospital of Shenzhen UniversityShenzhen518035China Institute of Hematology Shenzhen Second People’s Hospital/the First Affiliated Hospital of Shenzhen UniversityShenzhen518035China

The tumor microenvironment features over-expressed hydrogen peroxide(H_(2)O_(2)).Thus,versatile therapeutic strategies based on H_(2)O_(2) as a reaction substrate to generate hydroxyl radical(•OH)have been used as a prospective therapeutic method to boost anticancer ***,the limited Fenton catalysts and insufficient endogenous H_(2)O_(2) content in tumor sites greatly hinder•OH production,failing to achieve the desired therapeutic ***,supplying Fenton catalysts and elevating H_(2)O_(2) levels into cancer cells are effective strategies to improve•OH *** therapeutic strategies are systematically discussed in this ***,the challenges and future developments of hydroxyl radical-involved cancer therapy are discussed to improve therapeutic efficacy.

关键词： hydroxyl radical Fenton catalyst hydrogen peroxide cancer therapy

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hydroxyl radical formation upon dark oxidation of reduced iron minerals: Effects of iron species and environmental factors

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Chinese Chemical Letters 2019年第12期30卷 2241-2244页

作者： Ailing Zhu Yingying Guo Guangliang Liu Maoyong Song Yong Liang Yong Cai Yongguang Yin Institute of Environment and Health Jianghan UniversityWuhan 430056China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Laboratory of Environmental Nanotechnology and Health Effect Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Department of Chemistry and Biochemistry Florida International UniversityMiamiFL 33199United States

Dark formation of hydroxyl radical upon oxidation of reduced iron minerals plays an important role in the degradation and transformation of organic and inorganic ***,we compared the hydroxyl radical formation from various reduced iron minerals at different redox conditions.·OH production was generally observed from the oxidation of reduced iron minerals,following the order:mackinawite(FeS)>reduced nontronite(iron-bearing smectite clay)> pyrite(FeS2)> side rite(FeCO3).Structural Fe^2+ and dissolved O2 play critical roles in ·OH production from reduced iron minerals.·OH production increases with decreasing pH,and Cl^-has little effect on this *** importantly,dissolved organic matter significantly enhances ·OH production,especially under O2 purging,highlighting the importance of this process in ambient *** sunlight-independent pathway in which ’OH forms during oxidation of reduced iron minerals is helpful for understanding the degradation and transformation of various inorganic and organic pollutants in the redox-fluctuation environments.

关键词： Reduced iron minerals hydroxyl radical Dark oxidation Mackinawite Dissolved organic matter

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Rate Constants for Reaction Between hydroxyl radical and Dimethyl Sulfide Under Real Atmospheric Condition

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Chinese Journal of Chemical Physics 2008年第5期21卷 407-414页

作者： Hai-tao Wang Chang-jiang Hu Yu-jing Mu Yu-jie Zhang Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beifing 100085 China

The rate constants of the reaction between hydroxyl radical （OH-） and dimethyl sulfide （DMS） were investigated by using the relative methods in air, N2, and 02. Strong influences of ground state oxygen O（3p） on DMS consumption were found by the photolysis of HONO and CH3ONO as OH. sources, and the rate constants obtained in these systems varied significantly. The rate constants of the reaction between DMS and OH- （generated by photolysis of H2 O2） at room temperature were 8.56 × 10^-12, 11.31× 10^-12, and 4.50× 10^-12 cm3/（molecule.s）, in air, O2, and N2, respectively. The temperature dependence of the rate constants for OH- with DMS over the temperature range of 287-338 K was also investigated in nitrogen and air, and the Arrhenius expression was obtained as follows： kaire=（7.24±0.28）× 10^-13exp[（770.7±E97.2）/T], kN2 =（3.40±0.15） × 10^-11 exp[-- （590.3±165.9）/T].

关键词： Dimethyl sulfide hydroxyl radical Ground state oxygen Kinetics

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Reaction Kinetics of Trans-Sobrerol and 8-p-Menthen-1,2-diol with hydroxyl radical in Aqueous Solution： A Combined Experimental and Theoretical Study

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Chinese Journal of Chemical Physics 2015年第3期28卷 308-314,I0001,I0002页

作者： Yan Long Xin Tong Tong-mei Ma Li-ming Wang School of Chemistry & Chemical Engineering South China University of Technology Guangzhou 510640 China Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution Control South China University of Technology Guangzhou 510006 China

Trans-sobrerol （Sob） and 8-p-menthen-1,2-diol （Limo-diol） are the primary products in the atmospheric oxidation of α-pinene and limonene, respectively. Because of their low volatility, they associate more likely to the liquid particles in the atmosphere, where they are subject to the aqueous phase oxidation by the atmospheric oxidants. In this work, through experimental and theoretical study, we first provide the rate constants of Sob and Limo-diol reacting with hydroxyl radical （.OH） in aqueous solution at room temperature of 3044-3 K and 1 atm pressure, which are （3.05±0.5）×10 9 and （4.57±0.2）×10 9 L/（mol.s）, respectively. Quantum chemistry calculations have also been employed to demonstrate the solvent effect on the rate constants in aqueous phase and the calculated results agree well with the measurements. Some reaction products have been identified based on liquid chromatography combined with mass spectroscopy and theoretical calculations.

关键词： Unsaturated alcohols hydroxyl radical Aqueous-phase reaction Kinetic Theoretical calculations

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Theoretical Studies on the Reaction Mechanism of 1-Chloroethane with hydroxyl radical

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Chinese Journal of Structural Chemistry 2007年第6期26卷 695-702页

作者：王丙星王利 State Key Laboratory of Molecular Reaction Dynamics Dalian Institute of Chemical Physics Chinese Academy of Sciences Graduate School of the Chinese Academy of Sciences Beijing 100039 China

The reaction mechanism of 1-chloroethane with hydroxyl radical has been investigated by using density functional theory （DFT） B3LYP/6-31G （d, p） method. All bond dissociation enthalpies were computed at the same theoretical level. It was found that hydrogen abstraction pathway is the most favorable. There are two hydrogen abstraction pathways with activation barriers of 0.630 and 4.988 kJ/mol, respectively, while chlorine abstraction pathway was not found. It was observed that activation energies have a more reasonable correlation with the reaction enthalpy changes （ΔHr） than with bond dissociation enthalpies （BDE）.

关键词： bond dissociation enthalpies B3LYP 1-chloroethane hydroxyl radical reaction mechanism

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Effect of substituents in hydroxyl radical-mediated degradation of azo pyridone dyes: Theoretical approaches on the reaction mechanism

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Journal of Environmental Sciences 2020年第12期32卷 14-21页

作者： J.Dostanic M.Hus D.Loncarevic Institute of Chemistry Technology and MetallurgyUniversity of Belgrade(National Institute)Department of Catalysis and Chemical EngineeringNjegoševa 12BelgradeRepublic of Serbia Department of Catalysis and Chemical Reaction Engineering National Institute of ChemistryHajdrihova 19LjubljanaSlovenia

Understanding the degradation behavior of azo dyes in photocatalytic wastewater treatment is of fundamental and practical importance for their application in textile-processing and other coloration industries. In this study, quantum chemistry, as density functional theory, was used to elucidate different degradation pathways of azo pyridone dyes in a hydroxyl radical(HO ·)-initiated photocatalytic system. A series of substituted azo pyridone dyes were synthesized by changing the substituent group in the para position of the benzene moiety, ranging from strong electron-donating to strong electron-withdrawing groups. The effect of dye molecular structure on the photocatalytic degradation reaction mechanism was analyzed and quantification of substituent effects on the thermodynamic and kinetics parameters was performed. Potential energy surface analysis revealed the most susceptible reaction site for the HO ·attack. The calculated reaction barriers are found to be strongly affected by the nature of substituent group with a good correlation using Hammett σp constants and experimentally determined reaction rates. The stability of pre-reaction complexes and transition state complexes were analyzed applying the distortion-interaction model. The increased stability of the transition state complexes with the distancing from the substituent group has been established.

关键词： Quantum chemical calculation Density functional theory Azo dye Reaction mechanism Photocatalytic degradation hydroxyl radical Hammett equation Substituent effect

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Enhanced hepatic metabolic perturbation of polystyrene nanoplastics by UV irradiation-induced hydroxyl radical generation

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Journal of Environmental Sciences 2024年第8期142卷 259-268页

作者： Shiyu He Jingran Wang Lihong Zhou Zhen Mao Xiaodan Zhang Jin Cai Peili Huang School of Public Health and Beijing Key Laboratory of Environmental Toxicology Capital Medical UniversityBeijing 100069China

The environmental behavior of and risks associated with nanoplastics(NPs)have attracted considerable ***,compared to pristine NPs,environmental factors such as ultraviolet(UV)irradiation that lead to changes in the toxicity of NPs have rarely been *** evaluated the changes in morphology and physicochemical properties of polystyrene(PS)NPs before and after UV irradiation,and compared their hepatotoxicity in *** results showed that UV irradiation caused particle size reduction and increased the carbonyl index(CI)and negative charge on the particle ***-aged PS NPs(aPS NPs)could induce the generation of hydroxyl radicals(·OH),but also further promoted the generation of·OH in the Fenton reaction *** pathological damage was more severe in mice exposed to aPS NPs,accompanied by a large number of vacuoles and hepatocyte balloon-like changes and more marked perturbations in blood glucose and serum lipoprotein,alanine aminotransferase and aspartate aminotransferase *** addition,exposure to PS NPs and aPS NPs,especially aPS NPs,triggered oxidative stress and significantly damaged the antioxidant capacity of mice *** with PS NPs,exposure to aPS NPs increased the number of altered metabolites in hepatic and corresponding metabolic pathways,especially glutathione *** research suggests that UV irradiation can disrupt the redox balance in organisms by promoting the production of·OH,enhancing PS NPs-induced liver damage and metabolic *** study will help us understand the health risks of NPs and to avoid underestimation of the risks of NPs in nature.

关键词： Polystyrene nanoplastics Ultraviolet-aged nanoplastics Metabolic pathway Metabolomics hydroxyl radical

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Numerical analysis of quantitative measurement of hydroxyl radical concentration using laser-induced fluorescence in flame

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Chinese Physics B 2016年第6期25卷 157-164页

作者：陈爽苏铁郑尧邦陈力刘亭序李仁兵杨富荣 Science and Technology on Scramjet Laboratory China Aerodynamics Research and Development Center Hypervelocity Aerodynamics Institute Mianyang 621000 China China Aerodynamics Research and Development Center Mianyang 621000 China

The aim of the present work is to quantitatively measure the hydroxyl radical concentration by using LIF（laserinduced fluorescence） in *** detailed physical models of spectral absorption lineshape broadening,collisional transition and quenching at elevated pressure are *** fine energy level structure of the OH molecule is illustrated to understand the process with laser-induced fluorescence emission and others in the case without radiation,which include collisional quenching,rotational energy transfer（RET）,and vibrational energy transfer（VET）.Based on these,some numerical results are achieved by simulations in order to evaluate the fluorescence yield at elevated *** results are useful for understanding the real physical processes in OH-LIF technique and finding a way to calibrate the signal for quantitative measurement of OH concentration in a practical combustor.

关键词： laser-induced fluorescence hydroxyl radical quenching quantitative measurement

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Determination of atmospheric hydroxyl radical by HPLC coupled with electrochemical detection

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Journal of Environmental Sciences 2008年第1期20卷 28-32页

作者： LIU Bin WANG Hui-xiang College of Environmental Sciences Peking University Beijing 100871 China

The hydroxyl radical （·OH） plays a central role in the oxidation and removal of many atmospheric compounds. Measurement of atmospheric ·OH is very difficult because of its high reactivity and low atmospheric abundance. In this article, a simple and highly sensitive method, high performance liquid chromatography coupled with coulometric detection （HPLC-CD）, was developed to determine ·OH indirectly by determining its reaction products with salicylic acid （SAL）, 2,3-dihydroxybenzoic acid （2,3-DHBA）, and 2,5-dihydroxybenzoic acid （2,5-DHBA）. Under the optimum conditions for its determination, 2,3-DHBA and 2,5-DHBA could be well separated and the detection limits for 2,3-DHBA were 3 ×10^-10 mol/L and for 2,5-DHBA were 1.5 ×10^-10 mol/L, which were lower than most previous reports. This method was also applied to measure atmospheric hydroxyl radical levels and demonstrated the feasibility in clean and polluted air.

关键词： electrochemical detection HPLC hydroxyl radical troposphere

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