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A simple catalyst for aqueous phase Suzuki reactions based on palladium nanoparticles immobilized on an ionic polymer

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Science China Chemistry 2016年第4期59卷 482-486页

作者： Saeideh Ghazali-Esfahani Emilia Paunescu Mojtaba Bagherzadeh Zhaofu Fei Gabor Laurenczy paul j.dyson Institut des Sciences et Ingénierie Chimiques Ecole Polytechnique Fédérale de LausanneLausanne CH-I O15Switzerland Chemistry Department Sharif University of TechnologyTehran 11155-3615lran

Palladium nanoparticles immobilized on a cross-linked imidazolium-containing polymer were evaluated as a catalyst for Suzuki carbon-carbon cross-coupling reactions using water as the solvent. The nanocatalysts show good catalytic activities for aryl iodides and aryl bromides and moderate activity with aryl chloride substrates. Coupling of sterically hindered substrates could also be achieved in reasonable yields. The heterogeneous catalyst is stable, can be stored without precautions to exclude air or moisture, and can be easily recycled and reused.

关键词： catalysis biphasic catalysis polymeric ionic liquids nanoparticles aqueous phase catalysis Suzuki reaction

Bacterial diversity and distribution in the southeast edge of the Tengger Desert and their correlation with soil enzyme activities

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journal of Environmental Sciences 2012年第11期24卷 2004-2011页

作者： Wei Zhang Gaosen Zhang Guangxiu Liu Zhibao Dong Tuo Chen Manxiao Zhang paul j.dyson Lizhe An Key Laboratory of Desert and Desertification Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of SciencesLanzhou 730000China School of Life Sciences Lanzhou UniversityLanzhou 730000China Institute of Life Science College of MedicineSwansea UniversitySwansea SA28PPUK

The nature of microbial communities and their relation to enzyme activities in desert soils is a neglected area of investigation. To address this, the bacterial diversity and distribution and soil physico-chemical factors were investigated in the soil crust, the soil beneath the crust and rhizosphere soil at the southeast edge of the Tengger Desert, using the denaturing gradient gel electrophoresis of 16S rRNA genes amplified by the polymerase chain reaction. Phylogenedc analysis of the sequenced DGGE bands revealed a great diversity of bacteria. The Proteobacteria, consisting of the α, β, and γsubdivisions, were clearly the dominant group at all depths and in rhizosphere soil. Analysis of the enzyme activities indicated that the rhizosphere soil of Caragana korshinskii exhibited the highest protease and polyphenol oxidase activities, and in the soil crust there were increased activities of catalase, urease, dehydrogenase and sucrase. The bacterial community abundance closely correlated with soil enzyme activities in different soils. The presence of Cyanobacteria correlated with significant increases in protease, catalase and sucrase in the soil crust, and increased urease in the rhizosphere soil of Artemisia ordosica. The occurrence of Acidobacteria was associated with significant increases in urease, dehydrogenase, and sucrase in the rhizosphere soil of C. korshinski. The presence of γ-Proteobacteria correlated with a significant increase in polyphenol oxidase in the rhizosphere soil ofA. ordosica. The study indicated a close relationship between the soil bacterial community and soil enzymes, suggesting the necessity of further investigations into bacterial function in this desert ecosystem.

关键词： Tengger Desert DGGE 16S rRNA bacterial community soil enzyme

Single-step conversion of lignin monomers to phenol: Bridging the gap between lignin and high-value chemicals

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Chinese journal of Catalysis 2018年第9期39卷 1445-1452页

作者： jiaguang Zhang Loris Lombardo Gokalp Gozaydin paul j.dyson Ning Yan Department of Chemical and Biomolecular Engineering National University of Singapore117585 Singapore School of Chemistry University of LincolnJoseph Banks LaboratoriesGreen LaneLincolnLN6 7DLUnited Kingdom Institute of Chemical Sciences and Engineering Ecole Polytechnique Fédérale de Lausanne （EPFL） CH‐1015Switzerland

Transformation of lignin into high-value chemicals is hampered by the complexity of monomers obtained from lignin depolymerization. Here we report a strategy, composed of hy-dro-demethoxylation and de-alkylation reactions, that is able to chemically converge various lig-nin-derived phenolic monomers into phenol in a single-step. Using 2-methoxy-4-propylphenol as a model compound, Pt/C exhibited the best performance in hydro-demethoxylation reaction afford-ing 80% 4-propylphenol from 2-methoxy-4-propylphenol, while H-ZSM-5 was identified as the most suitable catalyst for de-alkylation, achieving 83% yield of phenol from 4-propylphenol. Since the two catalysts operate under compatible conditions, combining the two catalysts to simultane-ously promote both hydro-demethoxylation and de-alkylation reactions was achieved. Configura-tion of how to organize the catalysts is a critical parameter, where the physical mixture of the two was most effective, providing over 60% phenol from 2-methoxy-4-propylphenol in a single-step.

关键词： LigninPhenol ZeoliteDe‐alkylation Hydro‐demethoxylation

Highly Efficient and Stable FAPbI_(3) Perovskite Solar Cells and Modules Based on Exposure of the(011)Facet

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Nano-Micro Letters 2023年第9期15卷 164-174页

作者： Kai Zhang Bin Ding Chenyue Wang Pengju Shi Xianfu Zhang Cheng Liu Yi Yang Xingyu Gao Rui Wang Li Tao Keith G.Brooks Songyuan Dai paul j.dyson Mohammad Khaja Nazeeruddin Yong Ding Beijing Key Laboratory of Novel Thin-Film Solar Cells North China Electric Power UniversityBeijing 102206People’s Republic of China Institut des Sciences et Ingénierie Chimiques Ecole Polytechnique Fédérale de Lausanne(EPFL)Lausanne 1015Switzerland Shanghai Synchrotron Radiation Facility(SSRF) Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204People’s Republic of China School of Engineering Westlake University and Institute of Advanced TechnologyWestlake Institute for Advanced StudyHangzhou 310024People’s Republic of China Hubei Yangtze Memory Laboratories Wuhan 430205People’s Republic of China School of Microelectronics Hubei UniversityWuhan 430062People’s Republic of China

Perovskite crystal facets greatly impact the performance and stability of their corresponding photovoltaic *** to the(001)facet,the(011)facet yields better photoelectric properties,including higher conductivity and enhanced charge carrier ***,achieving(011)facet-exposed films is a promising way to improve device ***,the growth of(011)facets is energetically unfavorable in FAPbI_(3) perovskites due to the influence of methylammonium chloride ***,1-butyl-4-methylpyridinium chloride([4MBP]Cl)was used to expose(011)***[4MBP]^(+)cation selectively decreases the surface energy of the(011)facet enabling the growth of the(011)***[4MBP]^(+)cation causes the perovskite nuclei to rotate by 45°such that(011)crystal facets stack along the out-of-plane ***(011)facet has excellent charge transport properties and can achieve better-matched energy level *** addition,[4MBP]Cl increases the activation energy barrier for ion migration,suppressing decomposition of the *** a result,a small-size device(0.06 cm2)and a module(29.0 cm2)based on exposure of the(011)facet achieved power conversion efficiencies of 25.24%and 21.12%,respectively.

关键词： Renewable energy Perovskite solar cell Perovskite solar module Facet engineering

经由木材中的木质素组分制备“汽油”,“柴油”和甲醇

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经由木材中的木质素组分制备“汽油”,“柴油”和甲醇

中国化学会第26届学术年会绿色化学分会场

作者：颜宁赵晨 paul j.dyson 王晨刘凌涛寇元北京大学绿色化学研究中心北京分子科学国家实验室北京大学化学与分子工程学院北京大学绿色化学研究中心北京分子科学国家实验室北京大学化学与分子工程学院北京大学绿色化学研究中心北京分子科学国家实验室北京大学化学与分子工程学院北京大学绿色化学研究中心北京分子科学国家实验室北京大学化学与分子工程学院北京大学绿色化学研究中心北京分子科学国家实验室北京大学化学与分子工程学院北京大学绿色化学研究中心北京分子科学国家实验室北京大学化学与分子工程学院

＜正＞木质素与纤维素、半纤维素并称为植物体的三大组成部分。木质素是一种芳环聚合物,由单体通过C-O键或者C-C连接起来。通过使用贵金属催化剂,在一定的条件下,木质素可通过C-O键断

关键词：木质素贵金属催化解聚

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方形Rh纳米粒子生长机理解析

方形Rh纳米粒子生长机理解析

Surface engineering with ionic polymers on membranes for boron removal

中国化学会第28届学术年会

作者：姚思宇袁媛肖超贤寇元 paul j.dyson 颜宁 Tsunehiro Tanaka 北京大学理论与计算中心北京大学绿色化学中心北京大学化学与分子工程学院 Institut des Sciences et Ingenierie Chimiques Ecole Polytechnique Federale de Lausanne(EPFL)Lausanne

＜正＞本文采用原位XAFS及MALDI-TOFMS,TEM,XRD,UV-Vis Spectroscopy等非原位表征手段深入研究了乙二醇还原法制备的方形Rh纳米粒子的生长机理。对原位XAFS的数据分析发现方形Rh纳米粒子的生长过程分为配体取代、缓慢成核、

关键词： Rh纳米粒子成核生长机理原位XAFS 极限成核物种

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Frontiers of Chemical Science and Engineering 2024年第5期18卷 61-69页

作者： Xiting Zhang Chenyi Fang j paul Chen Sui Zhang Department of Chemical and Biomolecular Engineering National University of SingaporeSingapore 117576Singapore Department of Civil and Environmental Engineering National University of SingaporeSingapore 119260Singapore College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060China

Removal of boric acid from seawater and wastewater using reverse osmosis membrane technologies is imperative and yet remains inadequately addressed by current commercial *** research efforts performed post-modification of reverse osmosis membranes to enhance boron rejection,which is usually accompanied by substantial sacrifice in water *** study delves into the surface engineering of low-pressure reverse osmosis membranes,aiming to elevate boron removal efficiency while maintaining optimal salt rejection and water *** were modified by the self-polymerization and co-deposition of dopamine and polystyrene sulfonate at varying ratios and *** surfaces became smoother and more hydrophilic after *** optimum membrane exhibited a water permeability of 9.2±0.1 L·m^(-2)·h^(-1)·bar^(-1),NaCl rejection of 95.8%±0.3%,and boron rejection of 49.7%±0.1% and 99.6%±0.3% at neutral and alkaline pH,*** water permeability is reduced by less than 15%,while the boron rejection is 3.7 times higher compared to the blank *** research provides a promising avenue for enhancing boron removal in reverse osmosis membranes and addressing water quality concerns in the desalination process.

关键词： membrane low-pressure reverse osmosis boron surface engineering

A marathon,not a sprint:Increasing population physical activity as a legacy of sports mega-events

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journal of Sport and Health Science 2024年第6期13卷 732-735页

作者： Fiona C.Bull paul j.Simpson Physical Activity Unit Department of Health PromotionWorld Health OrganizationGeneva CH-1211Switzerland The BMj London WC1H 9JPUK

*** matters The withdrawal of Australia as hosts for the Commonwealth Games in 2026 demonstrates that large international sporting events are more than just sporting mastery,medals,and *** also matters.1 The cost of hosting a major international tournament is eye-wateringly *** governments need to show that the billions of dollars of investment deliver a return beyond sporting glory to justify the resources that are spent.

关键词： return dollar sport

A vectorial model for the nonlinear gradient force exerted on metallic Rayleigh nanoparticles

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Chinese Optics Letters 2024年第2期22卷 207-213页

作者：朱政张聿全闵长俊 Aurèle j.LAdam H.paul Urbach 袁小聪 Research Center for Humanoid Sensing Research Institute of Intelligent SensingZhejiang LabHangzhou 311100China Nanophotonics Research Center Institute of Microscale Optoelectronics&State Key Laboratory of Radio Frequency Heterogeneous IntegrationShenzhen UniversityShenzhen 518060China Optics Research Group ImPhys DepartmentFaculty of Applied SciencesDelft University of TechnologyDelft 2628 CJThe Netherlands

Optical tweezers have proved to be a powerful tool with a wide range of *** gradient force plays a vital role in the stable optical trapping of *** scalar method is convenient and effective for analyzing the gradient force in traditional optical ***,when the third-order nonlinear effect of the nano-object is stimulated,the scalar method cannot adequately present the optical response of the metal nanoparticle to the external optical ***,we propose a theoretical model to interpret the nonlinear gradient force using the vector *** combining the optical Kerr effect,the polarizability vector of the metallic nanoparticle is derived.A quantitative analysis is obtained for the gradient force as well as for the optical potential *** vector method yields better agreement with reported experimental *** suggest that this method could lead to a deeper understanding of the physics relevant to nonlinear optical trapping and binding phenomena.

关键词： gradient forces nonlinear effect metallic nanoparticles