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Radical dehydroxymethylative fluorination of aliphatic primary alcohols and diverse functionalization ofα-fluoroimides via BF_(3)·OEt_(2)-catalyzed C-F bond activation

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Chinese Chemical Letters 2025年第1期36卷 239-243页

作者： Peng Wang Jianjun Wang Ni song Xin Zhou Ming Li Molecular Synthesis Center Key Laboratory of Marine MedicineChinese Ministry of EducationSchool of Medicine and PharmacyOcean University of ChinaQingdao 266003China Laboratory for Marine Drugs and Bioproducts Pilot National Laboratory for Marine Science and TechnologyQingdao 266237China

Ag_(2)CO_(3)-promoted dehydroxymethylative fluorination of aliphatic alcohols has been achieved with Selectfluor as both oxidant and fluorine *** reaction involvesβ-fragmentation of primary alkoxy radicals,followed by the fluorination of the resulting C-centered radical *** transformation proceeds under mild reaction conditions and exhibits a broad substrate scope,thus opening up a new entrance to the synthesis of fluorinated constructs includingα-fluoroimides and 1-fluoroalkyl benzoates as well as secondary and tertiary alkyl fluorides like versatile 2-fluoro-2-alkyl 1,3-propandiol *** divergent functionalization of the obtainedα-fluoroimides enables an efficient access to amine derivatives through C-F bond activation under the action of BF_(3)·OEt_(2).

关键词： Dehydroxymethylative fluorination Alkoxy radicals β-Fragmentation Silver catalysis C-F Bond activation

Precise gradient separation of nanoparticles using reduced graphene oxide-polyoxomolybdate membranes

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Science China Chemistry 2025年第1期68卷 209-216页

作者： Yixin Yang Wanlei Zhao Ruoxuan Zheng Hongqiang Li Wei Chen Yu-Fei song State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China Quzhou Institute for Innovation in Resource Chemical Engineering Quzhou 324000China

The purification and size sieving of nanoparticles(NPs)represents a significant scientific ***,the rGO-polyoxometalates(POMs=PMo_(12),Mo_(132)and Mo_(368))membranes were fabricated successfully via a simple and scalable POMsassisted in-situ photoreduction *** the mass ratio of rGO to PMo_(12)was 1:30,the resultant rGO-PMo_(12)membranes with highly ordered and uniform nanochannels of 1.0 nm can be obtained,which showed an accurate carbon quantum dots(CQDs)separation with a cut-off size approximately 1.0 *** increase of the size of the interlayered POMs from PMo_(12)(1.0 nm),{Mo132}(2.9 nm)to{Mo_(368)}(3.8 nm),the resultant rGO-PMo_(12),rGO-Mo_(132)and rGO-Mo_(368)exhibited precise gradient separation of CQDs and Au nanoparticles by size exclusion *** results pave a promising way to construct new twodimensional(2D)membranes for highly efficient size-selective separation.

关键词： reduced graphene oxide polyoxometalates membranes gradient separation nanoparticles

Potential role of tanycyte-derived neurogenesis in Alzheimer's disease

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Neural Regeneration Research 2025年第6期20卷 1599-1612页

作者： Guibo Qi Han Tang Jianian Hu Siying Kang song Qin Department of Anatomy Histologyand EmbryologySchool of Basic Medical SciencesFudan UniversityShanghaiChina State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science Fudan UniversityShanghaiChina

Tanycytes, specialized ependymal cells located in the hypothalamus, play a crucial role in the generation of new neurons that contribute to the neural circuits responsible for regulating the systemic energy balance. The precise coordination of the gene networks controlling neurogenesis in naive and mature tanycytes is essential for maintaining homeostasis in adulthood. However, our understanding of the molecular mechanisms and signaling pathways that govern the proliferation and differentiation of tanycytes into neurons remains limited. This article aims to review the recent advancements in research into the mechanisms and functions of tanycyte-derived neurogenesis. Studies employing lineage-tracing techniques have revealed that the neurogenesis specifically originating from tanycytes in the hypothalamus has a compensatory role in neuronal loss and helps maintain energy homeostasis during metabolic diseases. Intriguingly,metabolic disorders are considered early biomarkers of Alzheimer's disease. Furthermore,the neurogenic potential of tanycytes and the state of newborn neurons derived from tanycytes heavily depend on the maintenance of mild microenvironments, which may be disrupted in Alzheimer's disease due to the impaired blood–brain barrier ***, the specific alterations and regulatory mechanisms governing tanycyte-derived neurogenesis in Alzheimer's disease remain unclear. Accumulating evidence suggests that tanycyte-derived neurogenesis might be impaired in Alzheimer's disease, exacerbating neurodegeneration. Confirming this hypothesis, however, poses a challenge because of the lack of long-term tracing and nucleus-specific analyses of newborn neurons in the hypothalamus of patients with Alzheimer's disease. Further research into the molecular mechanisms underlying tanycyte-derived neurogenesis holds promise for identifying small molecules capable of restoring tanycyte proliferation in neurodegenerative diseases. This line of investigation could pro

关键词： Alzheimer's disease blood–brain barrier ependymoglial cells hypothalamus metabolic diseases neural stem cells neurogenesis neuroinflammatory diseases neurons tanycyte

Mechanism by which Rab5 promotes regeneration and functional recovery of zebrafish Mauthner axons

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Neural Regeneration Research 2025年第6期20卷 1816-1824页

作者： Jiantao Cui Yueru Shen Zheng song Dinggang Fan Bing Hu Center for Advanced Interdisciplinary Science and Biomedicine of IHM Division of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefeiAnhui ProvinceChina

Rab5 is a GTPase protein that is involved in intracellular membrane trafficking. It functions by binding to various effector proteins and regulating cellular responses, including the formation of transport vesicles and their fusion with the cellular membrane. Rab5 has been reported to play an important role in the development of the zebrafish embryo;however, its role in axonal regeneration in the central nervous system remains unclear. In this study, we established a zebrafish Mauthner cell model of axonal injury using single-cell electroporation and two-photon axotomy techniques. We found that overexpression of Rab5 in single Mauthner cells promoted marked axonal regeneration and increased the number of intra-axonal transport vesicles. In contrast, treatment of zebrafish larvae with the Rab kinase inhibitor CID-1067700markedly inhibited axonal regeneration in Mauthner cells. We also found that Rab5 activated phosphatidylinositol 3-kinase(PI3K) during axonal repair of Mauthner cells and promoted the recovery of zebrafish locomotor function. Additionally, rapamycin, an inhibitor of the mechanistic target of rapamycin downstream of PI3K, markedly hindered axonal regeneration. These findings suggest that Rab5 promotes the axonal regeneration of injured zebrafish Mauthner cells by activating the PI3K signaling pathway.

关键词： axonal regeneration Mauthner cell nerve regeneration Rab5 zebrafish

Research progress of catalysts for direct coal liquefaction

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Journal of Energy Chemistry 2025年第1期100卷 481-497页

作者： Wei song Penggao Liu Xinyue Chen Ting Wang Chunrong He Rui Hao Kaiyu Liu State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources College of ChemistryXinjiang UniversityUrumqi 830017XinjiangChina College of Chemistry and Chemical Engineering Henan Polytechnic UniversityJiaozuo 454003HenanChina Hunan Provincial Key Laboratory of Chemical Power Sources College of Chemistry and Chemical EngineeringCentral South UniversityChangsha 410083HunanChina

Coal direct liquefaction technology is a crucial contemporary coal chemical technology for efficient and clean use of coal resources. The development of direct coal liquefaction technology and the promotion of alternative energy sources are important measures to guarantee energy security and economic security. However, several challenges need to be addressed, including low conversion rate, inadequate oil yield, significant coking, demanding reaction conditions, and high energy consumption. Extensive research has been conducted on these issues, but further exploration is required in certain aspects such as pyrolysis of macromolecules during the liquefaction process, hydrogen activation, catalysts' performance and stability, solvent hydrogenation, as well as interactions between free radicals to understand their mechanisms better. This paper presents a comprehensive analysis of the design strategy for efficient catalysts in coal liquefaction, encompassing the mechanism of coal liquefaction, catalyst construction,and enhancement of catalytic conversion efficiency. It serves as a comprehensive guide for further research endeavors. Firstly, it systematically summarizes the conversion mechanism of direct coal liquefaction, provides detailed descriptions of various catalyst design strategies, and especially outlines the catalytic mechanism. Furthermore, it addresses the challenges and prospects associated with constructing efficient catalysts for direct coal liquefaction based on an understanding of their action mechanisms.

关键词： Direct coal liquefaction Catalysts Mechanismof action Solvent hydrogenation

Synergistically S/N self-doped biochar as a green bifunctional cathode catalyst in electrochemical degradation of organic pollutant

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Green Energy & Environment 2025年第1期10卷 214-230页

作者： Xuechun Wang Huizhong Wu Jiana Jing Ge song Xuyang Zhang Minghua Zhou Raf Dewil Key Laboratory of Pollution Process and Environmental Criteria Ministry of EducationCollege of Environmental Science and EngineeringNankai UniversityTianjin300350China Tianjin Key Laboratory of Environmental Technology for Complex Trans-Media Pollution Nankai UniversityTianjin300350China Tianjin Advanced Water Treatment Technology International Joint Research Center College of Environmental Science and EngineeringNankai UniversityTianjin300350China Department of Chemical Engineering KU LeuvenJ.De Nayerlaan 5Sint-Katelijne-Waver B2860Belgium

Biomass-derived heteroatom self-doped cathode catalysts has attracted considerable interest for electrochemical advanced oxidation processes(EAOPs)due to its high performance and sustainable ***,we illustrated the morphological fates of waste leaf-derived graphitic carbon(WLGC)produced from waste ginkgo leaves via pyrolysis temperature regulation and used as bifunctional cathode catalyst for simultaneous H_(2)O_(2) electrochemical generation and organic pollutant degradation,discovering S/N-self-doping shown to facilitate a synergistic effect on reactive oxygen species(ROS)*** the optimum temperature of 800℃,the WLGC exhibited a H_(2)O_(2) selectivity of 94.2%and tetracycline removal of 99.3%within 60 *** functional theory calculations and in-situ Fourier transformed infrared spectroscopy verified that graphitic N was the critical site for H_(2)O_(2) *** pyridinic N and thiophene S were the main active sites responsible for OH generation,N vacancies were the active sites to produce ^(1)O_(2) from O_(2).The performance of the novel cathode for tetracycline degradation remains well under a wide pH range(3–11),maintaining excellent stability in 10 *** is also industrially applicable,achieving satisfactory performance treating in real water *** system facilitates both radical and non-radical degradation,offering valuable advances in the preparation of cost-effective and sustainable electrocatalysts and hold strong potentials in metal-free EAOPs for organic pollutant degradation.

关键词： Biochar S and N self-doping H_(2)O_(2)production In-situ FTIR Metal-free electrochemical advanced oxidation processes

Alpha-decay properties of nuclei around neutron magic numbers

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Nuclear Science and Techniques 2025年第1期36卷 140-149页

作者： Ming Li Chu-Xin Chen Lan-Fang Xiao Yi Zhang song Luo Xiao-Hua Li School of Nuclear Science and Technology University of South ChinaHengyang 421001China PET‑CT Center Chenzhou First People’s HospitalChenzhou 423000China Hengyang Ecological Environment Monitor Center Hengyang 421001China China Certification and Inspection Group Hefei 230000China National Exemplary Base for International Science and Technology Collaboration of Nuclear Energy and Nuclear Safety University of South ChinaHengyang 421001China Cooperative Innovation Center for Nuclear Fuel Cycle Technology and Equipment University of South ChinaHengyang 421001China Key Laboratory of Low Dimensional Quantum Structures and Quantum Control Hunan Normal UniversityChangsha 410081China

By combining experimental α-decay energies and half-lives, the α-particle preformation factor for nuclei around neutron magic numbers N of 126, 152, and 162 were extracted using the two-potential approach. The nuclei around the shell closure were more tightly bound than adjacent nuclei. Additionally, based on the WS4 mass model (Wang et al., Phys. Lett.B 734, 215 (2014)), we extended the two-potential approach to predict the α-decay half-lives of nuclei around N values of178 and 184 with Z of 119 and 120. We believe that our findings will serve as guidelines for future experimental studies.

关键词： adecay Preformation factor Neutron magic number Heavy and superheavy nuclei

Orbital XY models in moiré superlattices

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Chinese Physics B 2025年第2期34卷 19-29页

作者： Yanqi Li Yi-Jie Wang Zhi-Da song International Center for Quantum Materials School of PhysicsPeking UniversityBeijing 100871China Hefei National Laboratory Hefei 230088China Collaborative Innovation Center of Quantum Matter Beijing 100871China

Moiré superlattices provide a new platform to engineer various many-body problems. In this work, we consider arrays of quantum dots(QD) realized on semiconductor moiré superlattices with a deep moiré potential. We diagonalize single QD with multiple electrons, and find degenerate ground states serving as local degrees of freedom(qudits) in the superlattice. With a deep moiré potential, the hopping and exchange interaction between nearby QDs become irrelevant,and the direct Coulomb interaction of the density–density type dominates. Therefore, nearby QDs must arrange the spatial densities to optimize the Coulomb energy. When the local Hilbert space has a two-fold orbital degeneracy, we find that a square superlattice realizes an anisotropic XY model, while a triangular superlattice realizes a generalized XY model with geometric frustration.

关键词： moirésuperlattices quantum dots XY model

Improvement of charge-transfer kinetics via MXene and cobalt containing polyoxometalate loading on CdS for photocatalytic hydrogen production

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Science China Chemistry 2025年第2期68卷 772-780页

作者： Yu Feng Xiao Fang Jinnuo Zang Bin song Chunlian Hu Xiaoyu Dong Yong Ding State Key Laboratory of Applied Organic Chemistry Key Laboratory of Advanced Catalysis of Gansu ProvinceCollege of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000China State Key Laboratory of Low Carbon Catalysis and Carbon Dioxide Utilization State Key Laboratory for Oxo Synthesis and Selective OxidationLanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China

Hydrogen is a renewable and clean energy,and photocatalytic water splitting for hydrogen evolution technology is a promising technical means to solve the development *** this study,the ternary composite Co_(8)POM@MXene–CdS hybrid catalyst was constructed and used for photocatalytic hydrogen *** the condition of AM 1.5G simulated sunlight,the photocatalytic H_(2) evolution rate of the ternary composite was 8.13 mmol g^(−1) h^(−1),which was more than 25 times higher than that of the bare *** means of synchronous illumination X-ray photoelectron spectroscopy(SI-XPS)and density functional theory(DFT)calculations,it was proved that the loading of MXene and Co_(8)POM improved the photogenerated carrier separation and immigration efficiency on *** photogenerated electrons transfer from CdS to ***_(8)POM containing the{Co_(4)O_(3)}quasi-cubane,as an oxidation co-catalyst,accepts photogenerated holes from CdS to catalyze the oxidation reaction of TEOA,which improves the photocatalytic hydrogen production activity and the stability of CdS.

关键词： CdS polyoxometalates MXene hybrid catalyst photocatalytic hydrogen evolution