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Roles of hydroxyl and oxygen vacancy of CeO_(2)·xH_(2)O in Pd-catalyzed ethanol electro-oxidation

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Science China Chemistry 2022年第5期65卷 877-884页

作者： Zhenyu Li Jiefei Li Zexuan Zheng Kunhong Jiang Tianrun Zheng Dongmin Wang Hang Wei Zhiming Shi Xiaotian Li Haibin Chu College of Chemistry and Chemical Engineering Inner Mongolia Engineering and Technology Research Center for Catalytic Conversion and Utilization of Carbon Resource MoleculesInner Mongolia UniversityHohhot 010021China College of Materials Science and Engineering Jilin UniversityChangchun 130022China College of Chemistry Jilin UniversityChangchun 130012China State Key Laboratory of Luminescence and Applications Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China

In the field of noble metal-catalyzed alcohol electro-oxidation reaction(AOR),huge attention is paid on the composition,size,facet,and structure of the metals,while the support engineering should also be ***_(2)has been widely used as a unique support in AOR,primarily due to its abundant oxygen vacancies(O_(v)).Herein,we report CeO_(2)·xH_(2)O nanoparticles with both massive hydroxyl groups(OH)and O_(v)remarkably enhance the catalytic activity and stability of Pd toward ethanol oxidation reaction(EOR).The CO striping experiments and density functional theory(DFT)calculations suggest that OH and O_(v)on CeO_(2)·xH_(2)O surface bring about a large downshift of Pd d-band center and a significant weakening of CO absorption on ***,OH and O_(v)also play synergic roles in the removal of toxic ***,the important roles of OH and O_(v)of CeO_(2)·xH_(2)O are confirmed in Pd-catalyzed *** facile CeO_(2)·xH_(2)O-enhanced strategy can contribute to the catalyst design for other energy conversion reactions.

关键词： electrocatalysis ceria hydroxyl oxygen vacancy ethanol oxidation reaction

Flame-retardancy cellulosic triboelectric materials enabled by hydroxyl ionization

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Frontiers of Chemical Science and Engineering 2024年第10期18卷 63-72页

作者： Xin Wang Huancheng Huang Fanchao Yu Pinle Zhang Xinliang Liu Guangxi Key Laboratory of Clean Pulp&Papermaking and Pollution Control School of Light Industry and Food EngineeringGuangxi UniversityNanning 530004China

Triboelectric nanogenerators(TENGs)are among the most promising available energy harvesting ***-based TENGs are flexible,renewable,and ***,the flammability of cellulose prevents it from being used in open-flame *** this study,the lattice of cellulose was adjusted by the hydroxyl ionization of cellulose molecules,and Na+was introduced to enhance the flame retardancy of cellulose nanofibers(CNFs).The experimental results showed that the amount of hydrogen bonding between cellulose molecules increased with the introduction of Na+and that the limiting oxygen index reached 36.4%.The lattice spacing of cellulose increased from 0.276 to 0.286 nm,and the change in lattice structure exposed more hydroxyl groups,which changed the polarity of *** surface potential of the fibers increased from 239 to 323 mV,the maximum open-circuit voltage was 25 V·cm–2,the short-circuit current was 2.10μA,and the output power density was 4.56μW·cm–*** with those of CNFs,the output voltage,current,and transferred charge increased by 96.8%,517%,and 23%,respectively,and showed good stability and reliability during cyclic *** study provides a valuable strategy for improving the performance of cellulose-based TENGs.

关键词： fibers hydroxyl transferred

Phase Stability and hydroxyl Vibration of Brucite Mg(OH)_(2) at High Pressure and High Temperature

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Chinese Physics Letters 2021年第3期38卷 111-115页

作者： Wei-Bin Gui Chao-Shuai Zhao Jin Liu Center for High Pressure Science and Technology Advanced Research(HPSTAR) Beijing 100094China

Brucite Mg(OH)_(2) is an archetypal hydrous mineral and it has attracted a great deal of ***,little is known about the evolution of hydroxyl groups in brucite with respect to subduction *** carried out Raman measurements up to 15.4 GPa and 874 K via an externally heated diamond anvil cell,investigating the stability of brucite under the conditions relevant to subducting *** hydroxyl vibration mode A_(1g)(I) of brucite is weakened under simultaneous high pressure-temperature ***,the presence of carbonated solution can destabilize the hydroxyl groups of brucite at low *** results suggest that brucite releases water when reacting with hydrogen carbonate ion to form magnesite MgCO_(3) in subduction *** implies that the global water cycle is largely coupled with the deep carbon cycle in Earth’s interior.

关键词： hydroxyl cycle implies

Microstructured hydroxyl environments and Raman spectroscopy in selected basic transition-metal halides

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Chinese Physics B 2011年第8期20卷 435-442页

作者：刘晓东孟冬冬萩原雅人郑旭光 Department of Physics Graduate School of Science and EngineeringSaga University Department of Physics College of ScienceTianjin Polytechnic University Department of Physics Faculty of Science and EngineeringSaga University

Raman vibrational spectra of the selected basic （hydroxyl OH and deuteroxyl OD） transition-metal halides, geomet- rically frustrated material series α-, β-, γ-Cu2（OH）3Cl, α-Cu2（OH）3Br, β-Ni2（OH）3Cl, β-Co2（OH）3Cl, β-Co2（OH）3Br, γ-Cu2（OD）3Cl, and β-Co2（OD）3Cl are measured at room temperature and analysed to investigate the relationship be- tween the microstructured OH environments and their respective Raman spectra. Among these selected samples, the last two are used to determine the OH stretching vibration region （3600 cm-1-3300 cm-1） and OH bending vibra- tion region （1000 cm-1-600 cm-1） of OH systems in the spectra. Through the comparative analysis of the distances d（metal-O）, d（O-halogen）, and d（OH）, the strong metal-O interaction and trimeric hydrogen bond （Car, C8 or C1 symmetry） are found in every material, but both determine simultaneously an ultimate d（OH）, and therefore an OH stretching vibration frequency. According to the approximately linear relationship between the OH stretching vibration frequency and d（OH）, some unavailable d（OH） are guessed and some doubtful d（OH） are suggested to be corrected. In addition, it is demonstrated in brief that the OH bending vibration frequency is also of importance to check the more detailed crystal microstructure relating to the OH group.

关键词： hydroxyl trimeric hydrogen bond Raman spectrum basic transition-metal halide

Ammonium Impacts on Vibrations of hydroxyl and Lattice of Phengite at High Temperature and High Pressure

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Journal of Earth Science 2021年第5期32卷 1278-1286页

作者： Weihua Huang Yan Yang Zeming Qi Wendi Liu Zhongping Wang Yan Liu Qunke Xia School of Earth Sciences Zhejiang UniversityHangzhou 310027China National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230026China Department of Physics University of Science and Technology of ChinaHefei 230026China

Dehydration in hydrous phases of the downgoing slab controls water release processes in subduction zones. Interplay between volatiles in hydrous minerals has complicated the previous knowledge of their dehydration. Phengite is an essential mineral carrying both hydrogen and nitrogen to the deep Earth. To further understand the link between nitrogen and dehydration process of phengite at an atomic level, we here carry out high temperature and high pressure vibrational spectroscopic investigations on hydroxyl and lattice of ammonium-bearing and ammonium-free phengites. The results show that heating to 800 oC hardly influences hydroxyl bonding strength, whereas pressure induces strengthening of hydrogen bonding until 10 GPa. Moreover, hydrogen transits between the sites with increasing temperature and pressure. The lattice modes soften with increasing temperature and stiffen under compression. Ammonium has no effect on hydroxyl bonding strength, but hinders hydrogen transition at high temperatures and high pressures. Ammonium does not influence the lattice at high pressures either, but delays softening of the lattice at high temperatures. These data unveil behavior of hydroxyl and lattice in phengite at high temperature and high pressure, and also evaluate ammonium impacts, shedding new lights on dehydration processes of phengite during subduction.

关键词： hydroxyl lattice ammonium phengite high temperature high pressure

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Reactions of tea polyphenol four constituents with hydroxyl radical: A pulse radiolytic study

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Science China Chemistry 1998年第3期41卷 295-300页

作者：姜岳姚思德林维真林念芸朱大元 Laboratory of Radiation Chemistry Shanghai Institute of Nuclear Research Chinese Academy of Sciences Shanghai China Shanghai Institute of Materia Medica Chinese Academy of Sciences Shanghai China

Using the electron pulse radiolytic techniques, the reactions between hydroxyl radical and tea polyphenol four constituents epigallocatechin gallate (EGCG), epicatechin gallate (ECG), epigallocatechin (EGC) and epicatechin (EC) have been investigated in detail, their corresponding rate constants for scavenging hydroxyl radicals have been determined to be 1.5 × 1010, 1.4 × 1010, 9.7 × 109and 9.2 x 109 dm3-mol?1-s?1, respectively. On the basis of their structures and transient absorption spectra, the OH adducts of EGCG and ECG undergo unimolecular elimination of gallate group.

关键词： electron pulse radiolysis hydroxyl radical transient absorption spectra tea polyphenol.

Proline accumulation in rice seedlings exposed to hydroxyl radical stress in relation to antioxidation

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Chinese Science Bulletin 1997年第10期42卷 855-859页

作者： Jiang, MY Guo, SC Zhang, XM Department of Biology Xiangtan Teachers College Xiangtan China

PROLINE(Pro)is an essential amino acid for proteins and free Pro extensively exists in *** accumulates in plant cells in response to water stress,salinity,low temperature,air pollu-tants,*** has been mainly studied for its role in the osmotic adjustment of plants subject-ed to drought and *** addition to acting as a cytoplasmic osmoticum,Pro

关键词： hydroxyl radical stress proiine accumulation lipid peroxidation antioxidation Oryza sativa L.

Facile Synthesis of Dendritic hydroxyl-terminated Cyanuric Chloride Derivatives and Their Properties

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Chinese Journal of Chemistry 2012年第7期30卷 1485-1489页

作者：林休休周建华徐冬梅 College of Chemistry Chemical Engineering and Materials ScienceNational Engineering Laboratory for Modern SilkKey Laboratory of Organic Synthesis of Jiangsu ProvinceJiangsu Key Laboratory of Advanced Functional Polymer Design and ApplicationSoochow UniversitySuzhouJiangsu 215123China (Suzhou)Zhongke Nanotech Coating Co.LTD SuzhouJiangsu 215024China

Novel dendritic compounds G1.5（OH）4 and G1.5（OH）8 with peripheral hydroxyl were synthesized under mild conditions from eyanuric chloride, ethylene diamine, ethanolamine and diethanolamine. The products could be separated and purified through dispersion and precipitation in organic solvents with good yields （over 93.0%） and high purity （above 98.0%, HPLC）. The structures of the products were characterized by 1R, MS, 1H NMR and elementary analysis. G1.5（OH）4 and Gl.5（OH）8 could be dissolved in polar solvents such as methanol, water and dimethylsulfoxide. TGA analysis showed that G1.5（OH）4 and G1.5（OH）8 had good thermo stability. The aqueous solutions ofG1.5（OH）4 and G1.5（OH）8 exhibited low surface tension.

关键词： dendritic cyanuric chloride ethylene diamine hydroxyl surface activity

Rearrangement reaction of the hydroxyl group of ω-hydroxy-alkyltriphenyl phosphonium bromides

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Chinese Journal of Chemistry 2000年第6期18卷 886-891页

作者：何美玉袁谷贺晓然 Department of Chemistry Peking UniversityBeijing 100871 China

No molecular ion peak from the Electron Impact lonization of eight co-hydroxyalkyltriphenyl phosphonium bromides(Ph3P+(CH2)nOHBr-,n=2-6,8-10)can be found,except a part of some relative powerful fragment ions can be observed *** compound forms a very characteristic ion(O=PPbj-1)+ at m/z 277 through hydroxyl rearrangement *** intensity of this ion is closely related with the size of the carbon chain of hydroxyalkyl and with temperature of ion source and temperature of sample *** above rearrangement reaction and the reaction to form ion at m/z 262 take place simultaneously,thus leading to strong *** n=2,ion at m/z 277 is the most powerful and becomes continuously the base *** n=3 and n=4,the intensity of ion at m/z 262 reaches the maximum,and is always the base peak,and the relative abundance of m/z 277 is only around 2%.At n=5,6,8,9,10,m/z 277 becomes base peak when the temperature of probe is below 300℃.But,when the temperature increases from 300℃to 350℃,m/z 262 suddenly becomes the base peak,which is not in direct proportional relation with the size of carbon *** is proved by MIKES and accurate mass that ion at m/z 277 produces a fragment ion(O=PPh2-2)+ at m/z 199 with the loss of the neutral benzene molecule.

关键词： Rearrangement reaction hydroxyl characteristic ion intensity base peak competition probe temperature