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Journal of Environmental Sciences 2015年第3期27卷 131-138页

作者： Ruiming Zhang Wei Yan Chuanyong Jing State Key laboratory of Environmental chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of Sciences

Soil and sediment play a crucial role in the fate and transport of perfiuorooctane sulfonate （PFOS） in the environment. However, the molecular mechanisms of major soil/sediment components on PFOS adsorption remain unclear. This study experimentally isolated three major components in soil/sediment： humin/kerogen, humic/fulvic acid （HA/FA）, and inorganic component after removing organics, and explored their contributions to PFOS adsorption using batch adsorption experiments and molecular dynamic simulations. The results suggest that the humin/kerogen component dominated the PFOS adsorption due to its aliphatic features where hydrophobic effect and phase transfer are the primary adsorption mechanism. Compared with the humin/kerogen, the HA/FA component contributed less to the PFOS adsorption because of its hydrophilic and polar characteristics. The electrostatic repulsion between the polar groups of HA/FA and PFOS anions was attributable to the reduced PFOS adsorption. When the soil organic matter was extracted, the inorganic component also plays a non-negligible role because PFOS molecules might form surface complexes on SiO2 surface. The findings obtained in this study illustrate the contribution of organic matters in soils and sediments to PFOS adsorption and provided new perspective to understanding the adsorption process of PFOS on micro-interface in the environment.

关键词： Humic/fulvic acid Humin/kerogen PFOS Adsorption Molecular dynamics

Preparation and evaluation of Zr-β-FeOOH for efficient arsenic removal

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Journal of Environmental Sciences 2013年第4期25卷 815-822页

作者： Xiaofei Sun Chun Hu Jiuhui Qu State Key laboratory of Environmental Aquatic chemistry Research Center for Eco-Environmental SciencesChinese Academy of Sciences

A Zr-β-FeOOH adsorbent for both As（Ⅴ） and As（Ⅲ） removal was prepared by a chemical co-precipitation method. Compared with β-FeOOH, the addition of Zr enhanced the adsorption capacities for As（Ⅴ） and As（Ⅲ）, especially As（Ⅲ）. The maximum adsorption capacities for As（Ⅲ） and As（Ⅴ） were 120 and 60 mg/g respectively at pH 7.0, much higher than for many reported adsorbents. The adsorption data accorded with Freundlich isotherms. At neutral pH, for As（Ⅴ）, adsorption equilibrium was approached after 3 hr, while for As（Ⅲ）, adsorption equilibrium was approached after 5 hr. Kinetic data fitted well to the pseudo second-order reaction model. As（Ⅴ） elimination was favored at acidic pH, whereas the adsorption of As（Ⅲ） by Zr-β-FeOOH was found to be effective over a wide pH range of 4-10. Competitive anions hindered the adsorption according to the sequence： phosphate 〉 silicate 〉 bicarbonate 〉 sulfate 〉 nitrate, while Ca2＋ and Mg2＋ increased the removal of As（Ⅲ） and As（Ⅴ） slightly. The high adsorption capability and good performance in other aspects make Zr-β-FeOOH a potentially attractive adsorbent for the removal of both As（Ⅲ） and As（Ⅴ） from water.

关键词： arsenic adsorbent adsorption kinetic Zr-β-FeOOH

Probing the catalytic activity of M-N_(4−x)O_(x) embedded graphene for the oxygen reduction reaction by density functional theory

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Frontiers of Chemical Science and Engineering 2021年第5期15卷 1206-1216页

作者： Fan Ge Qingan Qiao Xin Chen You Wu State Key laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu610500China School of chemistry and Materials Science Ludong UniversityYantai264025China Center for Computational chemistry and Molecular Simulation College of Chemistry and Chemical EngineeringSouthwest Petroleum UniversityChengdu610500China Oil&Gas Field Applied chemistry Key laboratory of Sichuan Province College of Chemistry and Chemical EngineeringSouthwest Petroleum UniversityChengdu610500China

In this work,the detailed oxygen reduction reaction(ORR)catalytic performance of M-N_(4−x)O_(x)(M=Fe,Co,and Ni;x=1−4)has been explored via the detailed density functional theory *** results suggest that the formation energy of M-N_(4−x)O_(x)shows a good linear relationship with the number of doped O *** adsorption manner of O_(2)on M-N_(4−x)O_(x)changed from end-on(x=1 and 2)to side-on(x=3 and 4),and the adsorption strength gradually *** on the results for binding strength of ORR intermediates and the Gibbs free energy of ORR steps on the studied catalysts,we screened out two highly active ORR catalysts,namely Co-N_(3)O_(1)and Ni-N_(2)O_(2),which possess very small overpotentials of 0.27 and 0.32 V,*** activities are higher than the precious Pt *** structure analysis reveals one of the reasons for the higher activity of Co-N_(3)O_(1)and Ni-N_(2)O_(2)is that they have small energy gaps and moderate highest occupied molecular orbital energy ***,the results of the density of states reveal that the O doping can improve the electronic structure of the original catalyst to tune the adsorption of the ORR intermediates.

关键词： M-N-C catalyst oxygen doping oxygen reduction reaction catalytic activity density functional theory

Poly-N-benzylaniline prepared in perchloric acid——a new soluble semiconducting polymer

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Chinese Journal of chemistry 1992年第4期10卷 295-303页

作者： LI,Zhuang DONG,Shao-Jun laboratory of Electroanalytical chemistry,Changchun Institute of Applied chemistry,Chinese Academy of Sciences,Changchun,Jilin 130022 laboratory of Electroanalytical chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun Jilin 130022

Chemical or electrochemical oxidation of N-benzylaniline in perehloric acid solution yields a highly colored polymer——poly-N-benzylaniline (PBAn).The polymer has good solubility in a num- ber of organic solvents in either acid or base *** room temperature,conductivity measurements on pressed pellets of the acid form PBAn give a conductivity of 9.3×10^(-6) S·cm^(-1).The soluble polymer was analyzed using a variety of common experimental techniques including UV-vis,IR,NMR,ESR spectroscopy,elemental analysis and electrochemieal *** experimental results showed that PBAn has a structure similar to polyaniline with the elimination of some benzyl groups.

关键词： Poly-N-benzylaniline prepared in perchloric acid acid a new soluble semiconducting polymer

Supramolecular Assemblies of (±-2,2'-Dihydroxy-1,1'-binaphthyl with 2,2'-Bipyridine and Naphthodiazine

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Chinese Journal of chemistry 2004年第9期22卷 1045-1051页

作者：吉保明陈花婷杜晨霞丁奎岭 Department of chemistry Luoyang Teacher's CollegeLuoyangHenan 471022 China Department of chemistry Zhengzhou University Zhengzhou Henan 450052China State Key laboratory of Organometallic chemistry Shanghai Institute of Organic Chemistry Shanghai 200032 China

Supramolecular assemblies of (±)-2,2'-dihydroxy-1,1'-binaphthyl (BINOL, A), with aza donor molecules in-cluding 2,2'-bipyridine (B) and naphthodiazine (C), have been synthesized and characterized by single-crystal X-ray diffraction methods. Two inclusion complexes crystallize in the triclinic system with P-1 space group. In the inclu-sion complex between A and B, two molecules of A and two molecules of B are linked each other by intermolecular hydrogen bonds with two molecules of water as the bridges, forming a centrosymmetric dimer with formula of A2(H2O)2B2; while in the inclusion complex between A and C, the molecule C virtually acts as a bridge to link molecules A through intermolecular O—H…N hydrogen bonds, forming a short-chain supramolecular block with a formula of A2C3. Besides the hydrogen bonding interaction between the host and guest molecules, p-p stacking interactions also play an important role in the solid-state packing of these two inclusion complexes. The structural information disclosed on the complex between dihydroxy compound and aza hydrogen bond acceptors in this work would be particularly important for the rational design of supramolecular organic functional materials.

关键词： dihydroxy-1 1'-binaphthyl 2 2'-bipyridine naphthodiazine hydrogen bonding supramolecular structure

Prediction of Glass Transition Temperatures of Polyarylates Using a Support Vector Machine Model

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Chinese Journal of Structural chemistry 2011年第7期30卷 943-950页

作者：张仕华谭正德 Network Information Center Hunan Institute of Engineering Key laboratory of Environmentally Friendly chemistry and Applications of Ministry of Education College of ChemistryXiangtan University College of chemistry and Chemical Engineering Hunan Institute of Engineering

A three-descriptor quantitative structure-property relationship （QSPR） model, based on the support vector machine （SVM） algorithm, was constructed to predict the glass transition temperatures （Tgs） ofpolyarylates with complex structures. A total of 50 polyarylates were randomly divided into three sets, viz., the training set （30 polymers）, validation set （10 polymers） and prediction set （10 polymers）. By adjusting various parameters by trial and error, the final optimum SVM model based on Austin Model 1 （AM1） calculation is a polynomial kernel with the parameters C of 100, ε of 1.00E-05 and d of 2. The root-mean-square （RMS） errors obtained from the training set, validation set and prediction set are 19.4, 12.8 and 15.5 K, respectively. Research results show that the proposed SVM model has better statistical quality than the previous models. Thus, applying the SVM algorithm to predict Tgs of polymers is feasible.

关键词： glass transition temperature structure-property relations support vector machine

Recent advances in the rational design of single-atom catalysts for electrochemical CO_(2) reduction

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Nano Research 2022年第11期15卷 9747-9763页

作者： Huoliang Gu Jing Wu Liming Zhang Department of chemistry and Shanghai Key laboratory of Molecular Catalysis and Innovative Materials Fudan UniversityShanghai 200438China

Electrochemical CO_(2) reduction(CO_(2)R)represents a sustainable way to store intermittent renewable energies and produce carbon-neutral fuels,yet the energy efficiency remains a huge bottleneck owning to its sluggish kinetics and complex reaction *** active,selective,and robust electrocatalysts are strongly demanded to accelerate CO_(2) conversion and deploy this technology to practical *** this review,we focus on single-atom catalysts(SACs),a unique category of electrocatalysts with atomically dispersed metal active sites,which have shown distinctive performances in CO_(2)R and offer an ideal platform for in-depth mechanistic studies at the atomic *** various SACs with attractive CO_(2)R performances have been reported,the relationship between electronic/geometric structure of SACs and the corresponding electrocatalytic performance still needs to be discussed with *** we take a broad overview on the recent progress in understanding the structure–function correlation of SACs in CO_(2)R,with the purpose of providing deep insights and guiding the future rational design of ***,we provide the fundamental understandings of CO_(2)R on SACs,following different reaction ***,we describe the progresses in the development of well-defined SACs and the mechanistic studies on the influences from particular structural parameters,such as first-shell and second-sphere coordination,conductive supports and interface with a secondary ***,some perspectives are highlighted on the path towards efficient CO_(2)R on SACs.

关键词： single-atom catalysts electrochemical CO_(2)reduction structure-function correlation rational design

Controlling exciton-exciton annihilation in WSe_(2) bilayers via interlayer twist

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Nano Research 2022年第5期15卷 4661-4667页

作者： Yuzhong Chen Bichuan Cao Cheng Sun Zedong Wang Hongzhi Zhou Linjun Wang Haiming Zhu Key laboratory of Excited-State Materials of Zhejiang Province Department of ChemistryZhejiang UniversityHangzhou 310027China

The twist angle between two van der Waals coupled monolayers has emerged as a new and powerful degree of freedom for engineering physical properties of semiconductor homo-and *** the interlayer twist has shown prominent effect on electronic and optical properties of transition metal dichalcogenide(TMD)bilayers,it remains unclear how it could be used to manipulate the exciton dynamics,especially exciton-exciton annihilation(EEA)process which is the dominant energy loss channel in TMDs under moderate to high exciton density due to strong Coulomb ***,we show that the twist angle in TMD bilayers can act as an effective knob to control the EEA ***,EEA rate constant increases from 1° twisted WSe_(2) bilayers(0.026 cm^(2)/s)by more than twice to 32° twisted bilayers(0.053 cm2/s)and then drops again in 60° twisted bilayers(0.019 cm^(2)/s).This twist-angle dependence can be attributed to the energy difference between indirect and direct excitons arising from the interlayer *** work opens up the possibility of artificially managing the exciton dynamics in TMD materials for optoelectronic applications via interlayer twist angle.

关键词： two-dimensional bilayer twist angle transient absorption exciton-exciton annihilation interlayer coupling

Conversion of polyethylene to gasoline:Influence of porosity and acidity of zeolites

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Frontiers in Energy 2023年第6期17卷 763-774页

作者： Chunyu LI Haihong WU Ziyu CEN Wanying HAN Xinrui ZHENG Jianxin ZHAI Jiao XU Longfei LIN Mingyuan HE Buxing HAN Shanghai Key laboratory of Green chemistry and Chemical Processes School of Chemistry and Molecular EngineeringEast China Normal UniversityShanghai 200062China Beijing National laboratory for Molecular Sciences CAS Laboratory of Colloid and Interface and ThermodynamicsCAS Research/Education Center for Excellence in Molecular SciencesCenter for Carbon Neutral ChemistryInstitute of ChemistryChinese Academy of SciencesBeijing 100190China School of Chemical Sciences University of Chinese Academy of SciencesBeijing 100049China Institute of Eco-Chongming Shanghai 202162China

Plastic waste is causing serious environmental problems. Developing efficient, cheap and stable catalytic routes to convert plastic waste into valuable products is of great importance for sustainable development, but remains to be a challenging task. Zeolites are cheap and stable, but they are usually not efficient for plastic conversion at a low temperature. Herein a series of microporous and mesoporous zeolites were used to study the influence of porosity and acidity of zeolite on catalytic activity for plastics conversion. It was observed that H-Beta zeolite was an efficient catalyst for cracking high-density polyethylene to gasoline at 240℃, and the products were almost C_(4)–C_(12) alkanes. The effect of porosity and acidity on catalytic performance of zeolites was evaluated, which clearly visualized the good performance of H-Beta due to high surface area, large channel system, large amount accessible acidic sites. This study provides very useful information for designing zeolites for efficient conversion of plastics.

关键词： plastics conversion polyethylene zeolites acidity porosity

Rhodium-Catalyzed Asymmetric Trifluoromethoxylation of Racemic Allylic Trichloroacetimidates

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CCS chemistry 2024年第8期6卷 1885-1894页

作者： Liyan Wang Yafeng Si Yu-Xin Luan Pingping Tang State Key laboratory and Institute of Elemento-Organic chemistry College of ChemistryNankai UniversityTianjin 300071

A rhodium/diene catalyzed asymmetric allylic trifluoromethoxylation reaction is reported,which afforded chiral trifluoromethoxylated allylic compounds in 52%–97%yields with up to 97%enantiomeric *** are the first examples of asymmetric allylic *** reactions proceed via a dynamic kinetic process that allowed for the use of racemic allylic trichloroacetimidates as *** functional theory calculations showed that the formation of the C–OCF_(3)bond occurs via outer-sphere nucleophilic ***,the presence of the allylic group in the products enabled them to be converted into a diverse array of optically active trifluoromethylated molecules that are otherwise difficult to access.

关键词： asymmetric trifluoromethoxylation trifluoromethyl arylsulfonates rhodium trichloroacetimidates chiral diene ligand