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Nighttime reactions of a series of unsaturated alcohols with NO_(3)•:Kinetics,products and mechanisms study

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Journal of Environmental Sciences 2025年第5期151卷 331-346页

作者： Yanyong xu Shengrui Tong Weiran Li Meifang Chen Lin Hu Hailiang Zhang Sufan wang Maofa Ge State Key Laboratory for Structural Chemistry of Unstable and Stable Species Chinese Academy of Sciences Research/Education Center for Excellence in Molecular SciencesInstitute of Chemistry Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China College of Chemistry and Material Science Anhui Normal UniversityWuhu 241000China College of Ecology and Environment Xinjiang UniversityUrumqi 830017China

Unsaturated alcohols are a class of Biogenic volatile organic compounds(BVOCs)emitted in large quantities by plants when damaged or under adverse environmental conditions,and studies on their atmospheric degradation at night are still *** used chamber experiments to study the gas-phase reactions of three unsaturated alcohols,E-2-penten-1-ol,Z-2-hexen-1-ol and Z-3-hepten-1-ol,with NO_(3)radicals(NO_(3)•)during the *** rate constants of these reactions were(11.7±1.76)×10^(−13),(8.55±1.33)×10^(−13)and(6.08±0.47)×10^(−13)cm^(3)/(molecule·s)at 298K and 760 Torr,*** contrast,the reaction rate of similar substances with ozone was about 10^(−18)cm^(3)/(molecule·s),which indicates that the reaction with NO_(3)•is themain oxidation pathway for unsaturated alcohols at *** molecule aldehydes and ketones were the main gas-phase organic products of the reaction of three aldehydes and ketones with NO_(3)•,and the total small molecule aldehydes and ketones yields can reach between 45%-60%.They mainly originate from the breakage of alkoxy radicals,and different breakage sites determine different product *** addition,the SOA yields of the three unsaturated alcohols with NO_(3)•were 7.1%±1.0%,12.5%±1.9%and 30.0%±4.5%,respectively,whichweremuch higher than those of similarly structured substances with O_(3)or OH radicals(•OH).The results of high-resolution mass spectrometry shows that the main components of Secondary organic aerosol(SOA)of the three unsaturated alcohols are dimeric compounds containing several nitrate groups,which are formed through the polymerization of oxyalkyl radicals.

关键词： Unsaturated alcohols Reaction rate Aldehyde and ketone products Secondary organic aerosol components Reaction mechanism

Mainchain conformation ordering self-assembly tailored room temperature phosphorescence emission

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Science China Chemistry 2025年第1期68卷 329-336页

作者： Yuzhu Li Yumeng Gao Feng Tian Yu wang Yuan Yao Shaoliang Lin Xiang Ma Binbin xu Shanghai Key Laboratory of Advanced Polymeric Materials Key Laboratory for Ultrafine Materials of Ministry of EducationSchool of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China Key Laboratory for Advance Materials and Feringa Noble Prize Scientist Joint Research Centre Frontiers Science for Materiobiology and Dynamic ChemistrySchool of Chemistry and Molecular EngineeringEast China University of Science&TechnologyShanghai 200237China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China

Developing organic room-temperature phosphorescence(RTP)materials with a wide range of tunable-emission is significant in expanding the applications of RTP ***,we rationally designed amphiphilic alternating copolymers poly(1,2-bis(4-alkoxyphenyl)ethane-1,2-dione-alt-(ethylene glycol)x)(P(Bz-alt-EGx))that combined the advantage of alternating benzil and EGxskeleton,and tunable mainchain *** a mainchain conformation ordering assembly(COA)process,P(Bz-alt-EGx)self-assembled into well-defined platelets,and such assemblies emitted blue RTP at ca.425 nm due to the ordered folded-chain conformation and confined *** contrast,traditional self-assembly(TA)of P(Bz-alt-EGx)obtained less ordered aggregates,such as asymmetric worms,vesicles,and rod-like *** resultant less ordered aggregates exhibited yellow-green RTP at ca.550 *** wide-tuning RTP emission in solution(between blue and yellow-green,over125 nm)is realized using the P(Bz-alt-EG_(x))alternating copolymers under the treatment of different self-assembly *** study uncovers a new strategy to tailor the RTP emission through different self-assembly pathways and holds great promise for the fabrication of advanced optical materials.

关键词： self-assembly conformation ordering alternating copolymer phosphorescence emission

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MAX-DOAS observations of pollutant distribution and transboundary transport in typical regions of China

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Journal of Environmental Sciences 2025年第5期151卷 652-666页

作者： Hongmei Ren Ang Li Zhaokun Hu Hairong Zhang Jiangman xu Xinyan Yang Jinji Ma Shuai wang School of Physics and Electronic Information Anhui Normal UniversityWuhu 241000China Key Laboratory of Environmental Optics and Technology Anhui Institute of Optics and Fine MechanicsHefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China University of Science and Technology of China Hefei 230026China School of Geography and Tourism Anhui Normal UniversityWuhu 241000China China National Environmental Monitoring Centre Beijing 100012China

Studying the spatiotemporal distribution and transboundary transport of aerosols,NO_(2),SO_(2),and HCHO in typical regions is crucial for understanding regional pollution *** a 2-year study using multi-axis differential optical absorption spectroscopy in Qingdao,Shanghai,Xi’an,and Kunming,we investigated pollutant distribution and transport across Eastern China-Ocean,Tibetan Plateau-Central and Eastern China,and China-Southeast Asia ***,pollutant distributionwas ***,frequently clouded and misty,exhibited consistently high aerosol optical depth throughout the *** Qingdao and Shanghai,NO_(2)and SO_(2),as well as SO_(2)in Xi’an,increased in *** HCHO in summer in Shanghai and Xi’an,especially Xi’an,suggests potential ozone pollution ***,pollutant transportation across interfaces was *** the Eastern China-Ocean interface,the gas transport flux was the largest among other interfaces,with the outflux exceeding the influx,especially in winter and *** input of pollutants from the Tibetan Plateau to central-eastern Chinawas larger than the output in winter and spring,with SO_(2)having the highest transport flux in *** pollution input from Southeast Asia to China significantly exceeded the output,with spring and winter inputs being 3.22 and 3.03 times the output,***,the transportation characteristics of a pollution event at Kunming were *** this period,pollutants were transported from west to east,with themaximum SO_(2)transport flux at an altitude of 2.87 km equaling 27.74μg/(m^(2)·s).It is speculated that this pollution was caused by the transport from Southeast Asian countries to Kunming.

关键词： Multi-Axis Differential Optical Absorption Spectroscopy (MAX-DOAS) Pollutants Spatiotemporal distribution Transboundary transport

Microdynamic modulation through Pt–O–Ni proton and electron “superhighway” for pH-universal hydrogen evolution

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Journal of Energy Chemistry 2025年第2期101卷 808-815页

作者： Dewen wang Yuting Chen Bohan Yao Tian Meng Yanchao xu Dongxu Jiao Zhicai Xing Xiurong Yang State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences University of Science and Technology of China Department of Chemistry Shenzhen Grubbs Institute and Guangdong Provincial Key Laboratory of Energy Materials for Electric Power Southern University of Science and Technology State Key Laboratory of Automotive Simulation and Control School of Materials Science and Engineering Jilin University

Optimizing the microdynamics in alkaline and neutral conditions is a significant but challenging task in developing pH-universal hydrogen evolution（HER） ***,a unique Pt-O-Ni bridge has been constructed to alter the coordination and electronic environment between Pt nanoparticles（Pt_n）and nickel metaphosphate（NPO） substrate（Pt-NPO）.Sufficient electron transfer from NPO to Pt_n to maintain an electron-rich environment and a low valence state of Pt_***,H*is produced from the H2O dissociation on Ni site and then spillover toward Pt sites to bind into H2,which makes up for the insufficient H2O dissociation ability of Pt in Volmer ***-NPO exhibits long-term stability and only need the overpotentials of 22.3,33.0 and 30.5 mV to attain 10 mA cm-2in alkaline,neutral and acidic media,*** anion-exchange membrane（AEM） water electrolyzer catalyzed by Pt-NPO shows high water electrolysis performance that a cell voltage of 1.73 V is needed to obtain the current density of500 mA cm-2in 1 M KOH at 80℃,at the same time maintains good stability for 350 *** regulation strategy proposed in this work is helpful for the design and synthesis of highly efficient pH-universal HER electrocatalysts.

关键词： Atomic and electronic regulation Hydrogen evolution reactions Metal-support interactions Microdynamics pH-universal HER electrocatalysts

Phase-transfer-shuttle generated in situ enables novel SN1-type fluorination of sulfonium ylide with hydrofluoric acid

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Science China Chemistry 2025年第2期68卷 641-648页

作者： Yisa Xiao Rui wang Zhaoxuan xu Qunchao Zhao Renyi Pang Tao Dong Long Lu Qilong Shen Key Laboratory of Fluorine and Nitrogen Chemistry and Advanced Materials Shanghai Institute of Organic ChemistryUniversity of Chinese Academy SciencesChinese Academy of SciencesShanghai 200032China

The development of a nucleophilic fluorination protocol using hydrofluoric acid as the fluoride source represents a long-sought goal in the field of organofluorine *** report herein the realization of such a reaction that employed alkyl-substituted sulfonium ylides as the *** key to the success of the protocol was attributed to two factors:First,as a Brϕnsted base,the ylide was able to be protonated by HFaq,thus serving as a phase-transfer shuttle generated in situ to bring F−from aqueous phase to the organic phase promoting desolvation of fluoride ***,after protonation,a sulfonium salt,a good leaving group,was generated and subsequent attacked by the fluoride to afford the alkyl *** investigation indicates that the reaction occurs via an SN1 *** of the nature of the cationic intermediate in the reaction,two attractive rearrangement-fluorination approaches including 1,2-aryl migration fluorination and ring-expansion fluorination were disclosed.

关键词： SN1 fluorination hydrofluoric acid sulfonium ylide cation rearrangement

Dual-function switchable terahertz surface plasmon device driven by a GST metasurface

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Photonics Research 2025年第1期13卷 98-105页

作者： G1UANGHONG xu QUAN LI HAO SU YISHENG DONG GUANxuAN GUO HUIRONG wang HAI HUANG TAI CHEN SHUANG wang xuEQIAN ZHANG zhen TIAN School of Electronic Engineering Tianjin University of Technology and Education Center for Terahertz Waves College of Precision Instrument and Optoelectronics Engineering and Key Laboratory of Optoelectronics Information and Technology (Ministry of Education) Tianjin University

Surface plasmons （SPs） are one of the most effective information carriers for on-chip systems due to their twodimensional propagation *** from the highly flexible designability,metasuraces have emerged as a promising route in realizing SP ***,related studies are mainly focused on passive ***,by introducing nonvolatile phase-change material Ge2Sb2Te5（GST） into the metasurface design,we experimentally demonstrate a dual-function switchable SP device in the terahertz ***,the device works as a spin-dependent directional plane-wave SP coupler when GST is in the amorphous state,while it works as a spin-dependent directional SP Fresnel zone plate （FZP） when GST is in the crystalline *** states of GST are switched back and forth using thermal excitation and nanosecond laser illumination,*** method is simple and robust,and can find broad applications in on-chip photonic devices.?2024Chinese Laser Press

关键词： Light transmission Liquid crystals Optical properties Photonic devices Surface plasmons Zone plates

Boosting characteristic emissions of lanthanide in Cs_(2)Ag_(0.6)Na_(0.4)InCl_(6-x)Br_(x) double perovskites via mixing halide

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Journal of Rare Earths 2025年第1期43卷 39-46,I0002页

作者： Shujian wang Dejian Chen Jie Hu Sisi Liang Kunyuan xu Maochun Hong Haomiao Zhu University of Science and Technology of China Hefei230026China Ganjiang Innovation Academy Chinese Academy of SciencesGanzhou341000China CAS Key Laboratory of Design and Assembly of Functional Nanostructures and Fujian Key Laboratory of Nanomaterials Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou350002China Xiamen Key Laboratory of Rare Earth Photoelectric Functional Materials Xiamen Research Center of Rare Earth MaterialsHaixi InstitutesChinese Academy of SciencesXiamen361021China

Lanthanide ions(Ln^(3+))doping provides a potential strategy to control over the luminescent properties of lead-free halide double perovskite nanocrystals(DP NCs).However,due to the low energy transfer efficiency between self-trapped exciton(STE)and Ln^(3+)ions,the characteristic emissions of Ln^(3+)ions are not ***,the energy transfer mechanism between STE and Ln^(3+)ions is also elusive and requires in-depth *** chose trace Bi^(3+)-doped Cs_(2)Ag_(0.6)Na_(0.4)InCl_(6-x)Br_(x) as a representative DP matrix to demonstrate that by tuning the bromide concentration,the Ln^(3+)emission can be greatly *** enhanced STE and Ln^(3+)ions energy transfer originates from the high covalency of Ln-Br bond,which contributes to improve ment of the characteristic emission of Ln^(3+)*** re,optical spectroscopy reveals that the energy transfer mechanism from DP to Eu^(3+)ions is different from all the other doped Ln^(3+)*** energy transfer from DP to Eu^(3+)ions is mostly through Eu-Br charge transfer while the other Ln^(3+)ions are excited by energy transfer from *** distinct energy transfer mechanism has resulted from the energy separation between the excited energy level of Ln^(3+)ions and the bottom of conduction band of *** increasing the energy separation,the energy transfer from STE to Ln^(3+)ions is less efficient because of the generation of a larger number of phonons and finally becomes impossible for Eu^(3+)*** results provide new insight into tuning the energy transfer of Ln^(3+)-doped DP NCs.

关键词： Double perovskitenanocrystal Lead free Lanthanideions Energytransfer Rare earths

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Recent progress in studying orbital forcing of late Amazonian climate changes on Mars from Polar Layered Deposits

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Earth and Planetary Physics 2025年第02期 435-443页

作者： Xiang Li xu wang XiaoGuang Qin State Key Laboratory of Lithospheric and Environmental Coevolution Institute of Geology and Geophysics Chinese Academy of Sciences University of Chinese Academy of Sciences

The polar layered deposits(PLD) of Mars can provide deep insight into paleoclimate changes over the planet's last several million years. Since the 1960s, researchers have studied almost all aspects of Martian PLD properties, searching for patterns that might reveal periodic characteristics of the planet's climate history. Although much progress has been made in our understanding of orbital periodicities reflected in the PLD, questions remain regarding how Martian orbital changes have affected the formation of the PLD and regarding the extent of climate information that is recorded in the PLD. Future studies of PLD should be carried out via integrated research that targets multi-profiles throughout the entire Martian polar regions that would clarify their general features at the hemisphere scale. Numerical modeling, coupled with modern observations of dust and water vapor transportation, should greatly advance our understanding of planetary climate evolution. Furthermore, future landing missions may help to clarify the paleoclimatic characteristics reflected in the PLD by drilling into these layered deposits and measuring mineralogical and geochemical compositions of the drilled samples.

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SensFL:Privacy-Preserving Vertical Federated Learning with Sensitive Regularization

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 385-404页

作者： Chongzhen Zhang Zhichen Liu Xiangrui xu Fuqiang Hu Jiao Dai Baigen Cai Wei wang School of Automation and Intelligence Beijing Jiaotong UniversityBeijing100044China Shuohuang Railway Development Co. Ltd.National Energy GroupCangzhou062350China Beijing Key Laboratory of Security and Privacy in Intelligent Transportation School of Computer Science and TechnologyBeijing Jiaotong UniversityBeijing100044China

In the realm of Intelligent Railway Transportation Systems,effective multi-party collaboration is crucial due to concerns over privacy and data *** Federated Learning(VFL)has emerged as a promising approach to facilitate such collaboration,allowing diverse entities to collectively enhance machine learning models without the need to share sensitive training ***,existing works have highlighted VFL’s susceptibility to privacy inference attacks,where an honest but curious server could potentially reconstruct a client’s raw data from embeddings uploaded by the *** vulnerability poses a significant threat to VFL-based intelligent railway transportation *** this paper,we introduce SensFL,a novel privacy-enhancing method to against privacy inference attacks in ***,SensFL integrates regularization of the sensitivity of embeddings to the original data into the model training process,effectively limiting the information contained in shared *** reducing the sensitivity of embeddings to the original data,SensFL can effectively resist reverse privacy attacks and prevent the reconstruction of the original data from the *** experiments were conducted on four distinct datasets and three different models to demonstrate the efficacy of *** results show that SensFL can effectively mitigate privacy inference attacks while maintaining the accuracy of the primary learning *** results underscore SensFL’s potential to advance privacy protection technologies within VFL-based intelligent railway systems,addressing critical security concerns in collaborative learning environments.

关键词： Vertical federated learning privacy defenses