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Synergistic asymmetric diarylation of tethered alkenes via C–H functionalization of simple(hetero)arenes

Science China Chemistry 2024年第8期67卷 2710-2718页

作者： Jian Yao Can Zhao lili Shao Xiaohong Huo Xiaoming Wang Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs Frontiers Science Center for Transformative MoleculesSchool of Chemistry and Chemical EngineeringShanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Organometallic Chemistry and Shanghai Hongkong Joint Laboratory in Chemical Synthesis Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China School of Chemistry and Materials Science Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China

By virtue of the atom-and step-economy, utilization of simple arenes as a supplant of pre-prepared aryl metal species or aryl halides for the synthesis of arylated chiral molecules has attracted great attention from the synthetic community. While transition-metal-catalyzed enantioselective diarylation of tethered alkenes has been employed to prepare important chiral cyclic compounds, the direct use of simple arenes as aryl precursors is still underdeveloped, probably due to the difficulties in the effective control of the reactivity, site-selectivity and/or enantioselectivity. Herein we report an asymmetric Pd/Ag dual metal catalytic system for the non-directed, site-and enantioselective domino Heck/intermolecular C–H functionalization of *** studies showed that Pd and Ag act in cooperation in the catalysis and the chiral bisphosphine ligand plays a bifunctional role, i.e., assisting the silver species in the cleavage of the aryl C–H bond, while inducing the enantioselectivity on direct complexation with palladium. This method provides an efficient approach to the corresponding chiral oxindoles with good enantiomeric excesses from a broad scope of arenes, including fluoroarenes, heteroarenes and several complex products derived from medicines or natural products.

关键词： asymmetric Pd/Ag dual metal catalytic system simple arenes C–H functionalization bifunctional role chiral oxindoles

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Recent progress on Sn_(3)O_(4)nanomaterials for photocatalytic applications

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International Journal of Minerals,Metallurgy and Materials 2024年第2期31卷 231-244页

作者： Xin Yu Congcong Li Jian Zhang lili Zhao Jinbo Pang Longhua Ding Institute for Advanced Interdisciplinary Research(iAIR) School of Chemistry and Chemical EngineeringUniversity of JinanJinan 250022China School of Sino-German Engineering Shanghai Technical Institute of Electronics and InformationShanghai 201411China Division of Systems and Synthetic Biology Department of Life SciencesChalmers University of Technology41296 GöteborgSweden

Tin(IV)oxide(Sn_(3)O_(4))is layered tin and exhibits mixed valence *** has emerged as a highly promising visible-light pho-tocatalyst,attracting considerable *** comprehensive review is aimed at providing a detailed overview of the latest advance-ments in research,applications,advantages,and challenges associated with Sn_(3)O_(4)photocatalytic *** fundamental con-cepts and principles of Sn_(3)O_(4)are ***_(3)O_(4)possesses a unique crystal structure and optoelectronic properties that allow it to ab-sorb visible light efficiently and generate photoexcited charge carriers that drive photocatalytic ***,strategies for the control and improved performance of Sn_(3)O_(4)photocatalytic nanomaterials are *** control,ion doping,and hetero-structure construction are widely employed in the optimization of the photocatalytic performance of Sn_(3)O_(4)*** effective imple-mentation of these strategies improves the photocatalytic activity and stability of Sn_(3)O_(4)***,the review explores the diverse applications of Sn_(3)O_(4)photocatalytic nanomaterials in various fields,such as photocatalytic degradation,photocatalytic hydro-gen production,photocatalytic reduction of carbon dioxide,solar cells,photocatalytic sterilization,and optoelectronic *** discus-sion focuses on the potential of Sn_(3)O_(4)-based nanomaterials in these applications,highlighting their unique attributes and ***,the review provides an outlook on the future development directions in the field and offers guidance for the exploration and de-velopment of novel and efficient Sn_(3)O_(4)-based *** the identification of emerging research areas and potential avenues for improvement,this review aims to stimulate further advancements in Sn_(3)O_(4)-based photocatalysis and facilitate the translation of this promising technology into practical applications.

关键词： photocatalysis Sn_(3)O_(4)nanomaterials building heterostructures antibacterial therapy water splitting

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The importance of data assimilation components for initial conditions and subsequent error growth

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Science China Earth Sciences 2024年第1期67卷 105-116页

作者： Zhongrui WANG Haohao SUN lili LEI Zhe-Min TAN Yi ZHANG Key Laboratory of Mesoscale Severe Weather Ministry of Educationand School of Atmospheric SciencesNanjing UniversityNanjing 210023China Frontiers Science Center for Critical Earth Material Cycling Nanjing UniversityNanjing 210023China

Despite a specific data assimilation method,data assimilation(DA)in general can be decomposed into components of the prior information,observation forward operator that is given by the observation type,observation error covariances,and background error *** a classic Lorenz model,the influences of the DA components on the initial conditions(ICs)and subsequent forecasts are systematically investigated,which could provide a theoretical basis for the design of DA for different scales of *** forecast errors undergo three typical stages:a slow growth stage from 0 h to 5 d,a fast growth stage from 5 d to around 15 d with significantly different error growth rates for ensemble and deterministic forecasts,and a saturation stage after 15 *** strategies that provide more accurate ICs can improve the *** assimilation is superior to offline assimilation,and a flow-dependent background error covariance matrix(Pf)provides better analyses than a static background error covariance matrix(B)for instantaneous observations and frequent time-averaged observations;but the opposite is true for infrequent time-averaged observations,since cycling simulation cannot construct informative priors when the model lacks predictive skills and the flow-dependent Pf cannot effectively extract information from low-informative observations as the static *** observations contain more information than time-averaged observations,thus the former is preferred,especially for infrequent observing ***,ensemble forecasts have advantages over deterministic forecasts,and the advantages are enlarged with less informative observations and lower predictive-skill model priors.

关键词： Data assimilation Atmospheric predictability Background error covariances Ensemble forecasts

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Interplay between microglia and environmental risk factors in Alzheimer's disease

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Neural Regeneration Research 2024年第8期19卷 1718-1727页

作者： Miaoping Zhang Chunmei Liang Xiongjin Chen Yujie Cai lili Cui Guangdong Key Laboratory of Age-Related Cardiac and Cerebral Diseases Affiliated Hospital of Guangdong Medical UniversityZhanjiangGuangdong ProvinceChina

Alzheimer s disease,among the most common neurodegenerative disorders,is chara cterized by progressive cognitive *** present,the Alzheimer’s disease main risk remains genetic ris ks,but major environmental fa ctors are increasingly shown to impact Alzheimer’s disease development and ***,the most important brain immune cells,play a central role in Alzheimer’s disease pathogenesis and are considered environmental and lifestyle"sensors."Factors like environmental pollution and modern lifestyles(e.g.,chronic stress,poor dietary habits,sleep,and circadian rhythm disorde rs)can cause neuroinflammato ry responses that lead to cognitive impairment via microglial functioning and phenotypic ***,the specific mechanisms underlying interactions among these facto rs and microglia in Alzheimer’s disease are ***,we:discuss the biological effects of air pollution,chronic stress,gut micro biota,sleep patterns,physical exercise,cigarette smoking,and caffeine consumption on microglia;consider how unhealthy lifestyle factors influence individual susceptibility to Alzheimer’s disease;and present the neuroprotective effects of a healthy *** intervening and controlling these environmental risk fa ctors at an early Alzheimer’s disease stage,understanding the role of microglia in Alzheimer’s disease development,and to rgeting strategies to to rget microglia,co uld be essential to future Alzheimer’s disease treatments.

关键词： Alzheimer’s disease chronic stress environmental factor gut microbiota microglia particulate matter with diameter<2.5μm

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Social Radars: Finding Targets in Cyberspace for Cybersecurity

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IEEE/CAA Journal of Automatica Sinica 2024年第2期11卷 279-282页

作者： lili Fan Changxian Zeng Yutong Wang Jiaqi Ma Fei-Yue Wang School of Information and Electronics Beijing Institute of TechnologyBeijing 100081China School of Science Dalian Minzu UniversityDalian 116600China State Key Laboratory for Management and Control of Complex Systems Institute of AutomationChinese Academy of SciencesBeijing 100190China Department of Civil and Environmental Engineering University of CaliforniaLos AngelesCA 90024 USA IEEE State Key Laboratory for Management and Control of Complex Systems Chinese Academy of SciencesBeijing 100190 Faculty of Innovation Engineering Macao University of Science and TechnologyMacao 999078China

INSPIRED by the insight from American political scientist Lasswell, who summarized the environmental role in societal surveillance [1], Schramm coined the term “social radar” [2] as it resembles the activities of radar in collecting and processing information, playing a crucial role in helping humans perceive changes in the internal and external environment and promptly adjusting adaptive behaviors.

关键词： prompt summarized insight

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C2-phenyl-substituted benzimidazolium-based covalent organic framework as efficient catalyst for CO_(2) conversion without solvents,metals,and cocatalysts

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Science China Chemistry 2024年第2期67卷 551-557页

作者： Zhenzhen Wu Jing Wang lili Liu Shang Guo Juan Li Xianming Zhang Shanxi Institute for Functional Food Shanxi Agricultural UniversityTaiyuan030031China Institute of Crystalline Materials Shanxi UniversityTaiyuan030006China Key Laboratory of Interface Science and Engineering in Advanced Materials College of ChemistryTaiyuan University of TechnologyTaiyuan030024China

Covalent organic frameworks(COFs) are a potential platform for carbon dioxide(CO_(2)) conversion owing to their periodic permanent porosity,adjustable structure,and chemical *** good catalytic performance in CO_(2) conversion,collaborative multifunctions should be strategically integrated into the catalytic system design and *** this study,a four-in-one high-efficiency catalyst was synthesized and tested for CO_(2) cycloaddition to form cyclic *** obtained Tp-MPB-BrCOF had a high nitrogen content,which enhanced its CO_(2) affinity through substantial Lewis acid-base or dipole-quadrupole interactions;moreover,the acid(protons transferring from oxygen(–OH) to nitrogen(–NH)),hydrogen bond donor(hydroxyl group),and Br-(nucleophile group) served as three active sites,further improving the catalyst *** results provide a basis for designing efficient and stable CO_(2)-conversion catalysts.

关键词： covalent organic framework C2-phenyl-substituted benzimidazolium CO_(2)conversion four-in-one catalyst

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Study of poly-disperse aerosols deposition in turbulent flow with different Reynolds numbers

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Particuology 2024年第6期89卷 32-43页

作者： Zhichao Gao Yongzheng Chen Dandi Zhang Peng Chen lili Tong Xuewu Cao School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai200240China China Nuclear Power Technology Research Institute Co. Ltd.Shenzhen518000China

The turbulent deposition mechanism is one of the main mechanisms of aerosol deposition in nuclear power plant *** experimental study of poly-disperse aerosol deposition in a horizontal tube is conducted,where the nominal Reynolds number(Re)is in a range of 3600–200,*** aerosol deposition velocity first increases and then decreases with the increase of Res,and at high Re,particle rebound occurs during aerosol deposition in the *** the Re is low,the aerosol deposition velocity increases with the increase of aerosol *** the Re is greater than 60,000,the deposition velocity first increases and then decreases with the increase of aerosol diameter due to particle surface rebound.A new aerosol deposition model has been developed by establishing the energy conservation equation of the rebounded particles in the viscous *** calculated results of the new model are in good agreement with these experimental results,and the error between the aerosol deposition velocity calculated by the model and experimental results is between−60%and 150%.

关键词： Aerosol Turbulent deposition Rebound High Reynolds number

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Preparation of α-High Strength Gypsum from Flue Gas Desulfurization Gypsum Pretreated by Hydrothermal-aging Method

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Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 75-81页

作者：苏一鑫 GAO lili 陈学青 LI Zhishui 李雲 CAO Jilin Engineering Research Center of Seawater Utilization Technology of Ministry of Education School of Chemical Engineering and TechnologyHebei University of TechnologyTianjin 300130China Heze Center for Disease Control and Prevention Heze 274010China Tianjin Bohua Yongli Chemical Industry Co. Ltd.Tianjin 300452China

The synthesis of α-calcium sulfate hemihydrate (α-CSH) from flue gas desulfurization (FGD)gypsum is a good way to realize the comprehensive utilization of FGD gypsum. To obtainα-CSH with the satisfactory performances, a facile hydrothermal-aging pretreatment process for FGD gypsum raw materials was proposed, where FGD gypsum was firstly hydrothermally converted to α-CSH whiskers, and α-CSH whiskers were further hydrated to synthesize CaSO4·2H2O (CSD) by aging under the regulation of N,N'-methylenebisacrylamide (MBA). The effects of aging time, MBA addition, aging temperature, and pH on the morphology of the synthesized CSD were investigated. The synthesized CSD crystals exhibit highly uniform prismatic morphology with the length of ca 100μm and the whiteness of 91.56%. The regulation mechanism of MBA was also illustrated. The synthesized CSD crystals with prismatic morphology were further used as raw materials to synthesize the short columnar α-CSH. The absolute dry compressive strength of paste prepared from the short columnar α-CSH is 40.85 MPa, which reaches α40 strength grade.

关键词： flue gas desulphurization gypsum α-calcium sulfate hemihydrate hydrothermal-aging method N,N'-methylenebisacrylamide prismatic CSD

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Simultaneous photocatalytic degradation and SERS detection of tetracycline with self-sustainable and recyclable ternary PI/TiO_(2)/Ag flexible microfibers

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Microsystems & Nanoengineering 2024年第2期10卷 101-113页

作者： Donglai Han Boyang Guo Yanru Li Wei Feng Keyan Liu Tianna Wu Yuchun Wan lili Wang Ming Gao Yang Liu lili Yang Maobin Wei Shuo Yang School of Materials Science and Engineering Changchun University of Science and Technology130022ChangchunChina College of Science Changchun University130022ChangchunChina Key Laboratory of Functional Materials Physics and Chemistry of the Ministry of Education Jilin Normal University130103ChangchunChina

Facile and efficient photocatalysts using sunlight,as well as fast and sensitive surface-enhanced Raman spectroscopy(SERS)substrates,are urgently needed for practical degradation of tetracycline(TC).To meet these requirements,a new paradigm for PI/TiO_(2)/Ag organic‒inorganic ternary flexible microfibers based on semiconducting titanium dioxide(TiO_(2)),the noble metal silver(Ag)and the conjugated polymer polyimide(PI)was developed by engineering a simple *** sunlight,the photocatalytic characteristics of the PI/TiO_(2)/Ag flexible microfibers containing varying amounts of Ag quantum dots(QDs)were evaluated with photocatalytic degradation of TC in aqueous *** results demonstrated that the amount of Ag affected the photocatalytic *** the tested samples,PI/TiO_(2)/Ag-0.07(93.1%)exhibited a higher photocatalytic degradation rate than PI/TiO_(2)(25.7%),PI/TiO_(2)/Ag-0.05(77.7%),and PI/TiO_(2)/Ag-0.09(63.3%).This observation and evaluation conducted in the present work strongly indicated a charge transfer ***,the PI/TiO_(2)/Ag-0.07 flexible microfibers exhibited highly sensitive SERS detection,as demonstrated by the observation of the Raman peaks for TC even at an extremely low concentration of 10–10 moles per *** excellent photocatalytic performance and SERS detection capability of the PI/TiO_(2)/Ag flexible microfibers arose from the Schottky barrier formed between Ag and TiO_(2)and also from the outstanding plasmonic resonance and visible light absorptivity of Ag,along with immobilization by the *** successful synthesis of PI/TiO_(2)/Ag flexible microfibers holds significant promise for sensitive detection and efficient photocatalytic degradation of antibiotics.

关键词： mechanism. photocatalytic ternary

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Research progress on short-term mechanical properties of FRP bars and FRP-reinforced concrete beams

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第2期11卷 245-270页

作者： lili Xing Shengjiang Sun Kuihua Mei Yiping Guo Zhenhong Yang School of Highway Chang'an UniversityXi'an 710064China

Fiber-reinforced polymer(FRP)bars have been increasingly recognized in the field of civil engineering due to their advantages of light weight,high strength and excellent *** bars can replace steel bars in concrete beams and effectively improve the durability of *** this paper,the literature relevant to the short-term mechanical properties of FRP bars and FRP-reinforced concrete beams was reviewed based on previous studies and practical engineering ***,the mechanical properties of FRP bars were *** types of fibers or steel and fibers can be combined to obtain hybrid fiber-reinforced polymer(HFRP)or steel-fiber composite bars(SFCB)with excellent mechanical performance,*** bond performance and bond-slip model between FRP bars and concrete were *** common bond-slip models were usually used to study the bond performance between carbon fiber-reinforced polymer(CFRP)bars or glass fiber-reinforced polymer(GFRP)bars and concrete,but changing the type of FRP bars will lead to larger ***,the experimental studies,theoretical calculation methods and finite element simulation methods of flexural/shear behavior of FRP-reinforced concrete beams were ***,their applications in practical engineering were discussed and the prospects of further research were *** is pointed out that FRP-reinforced ultra-high performance concrete(UHPC)beams,FRP-reinforced geopolymer concrete(GPC)beams,engineered cementitious composites(ECC)-FRP-reinforced concrete beams,prestressed FRP-reinforced concrete beams and steel/FRP hybrid-reinforced concrete beams can effectively improve the deformation resistance and poor ductility of pure FRP-reinforced concrete beams.

关键词： FRP bars Bond performance Flexural/shear behavior Civil engineering

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