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Development of ESIPT-based specific fluorescent probes for bioactive species based on the protection-deprotection of the hydroxyl

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Chinese Chemical Letters 2025年第2期36卷 49-56页

作者： Haixian Ren Yuting Du Xiaojing Yang Fangjun Huo Le zhang Caixia Yin Department of Chemistry Xinzhou Normal University Research Institute of Applied Chemistry Shanxi University Department of Chemistry The University of Texas at Austin Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education Key Laboratory of Materials for Energy Conversion and Storage of Shanxi Province Institute of Molecular ScienceShanxi University

Excited-state intramolecular proton-transfer (ESIPT) based fluorescence probes are particularly attractive due to their unique properties including environmental sensitivity, a large Stokes shift, and potential for ratiometric sensing. In general, ESIPT-based fluorophore incorporates an intramolecular hydrogen bonding interaction between a hydrogen bond donor (–oH and NH2are common) and a hydrogen bond acceptor(C=N and C=o). More, protection–deprotection of hydroxyl group as hydrogen bond donor could induce an off-on switch of ESIPT-based emission. Therefore, protection–deprotection of hydroxyl group has been the widely used strategy to design fluorescent probes, where the potential key issue is selecting a protective group that can specifically leave in the presence of the target analyte. In this review, we mainly summarize the specific protecting groups (sites) and deprotection mechanisms for biologically important species (including reactive sulfur species (RSS), reactive oxygen species (RoS), enzymes, etc.), and analyze the advantages and disadvantages of different protection mechanisms from some aspects including probe stability, selectivity, response rate and assay system, etc. Based on the aforementioned, we further point out the current challenges and the potential future direction for developing ESIPT-based probes.

关键词： Bioimaging ESIPT Fluorescence probe Protection-deprotection Specificity

on the Riemann–Hilbert problem for the reverse space-time nonlocal Hirota equation with step-like initial data

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Communications in Theoretical Physics 2025年第2期77卷 32-40页

作者： Bei-Bei Hu Ling zhang Zu-Yi Shen Ji Lin School of Mathematics and Finance Chuzhou University Applied Mathematics Research Center Chuzhou University Department of Physics Zhejiang Normal University

In this paper, we use the Riemann–Hilbert(RH) method to investigate the Cauchy problem of the reverse space-time nonlocal Hirota equation with step-like initial data: q(z, 0) = o(1) as z →-∞ and q(z, 0) = δ + o(1) as z → ∞, where δ is an arbitrary positive constant. We show that the solution of the Cauchy problem can be determined by the solution of the corresponding matrix RH problem established on the plane of complex spectral parameter λ. As an example, we construct an exact solution of the reverse space-time nonlocal Hirota equation in a special case via this RH problem.

关键词： nonlocal Hirota equation Cauchy problem Riemann-Hilbert problem step-like initial data

Spatiotemporal evolution of Ediacaran-Cambrian(ca.551–523 Ma)sponges in South China and their simulated contributions to marine oxygenation

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Science China Earth Sciences 2025年第2期68卷 549-563页

作者： Yan YE Lei zhang Can CHEN Shan CHANG Yuhao YI Qinglai FENG State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesWuhan 430074China School of Earth Science China University of GeosciencesWuhan 430074China Department of Geology Lund UniversityLund 22362Sweden Institute of Sedimentary Geology Chengdu University of TechnologyChengdu 610059China Key Laboratory of Deep-time Geography and Environment Reconstruction and Applications of Ministry of Natural Resources Chengdu University of TechnologyChengdu 610059China Second Geological Brigade of Hubei Geological Bureau Enshi 445000China College of Urban and Environmental Sciences Hubei Normal UniversityHuangshi 435002China Exploration and Development Research Institute SINOPEC Jianghan Oilfield CompanyWuhan 430223China

The origin and evolution of sponges have attracted interest,not only because they are among the most basal metazoans,but also because they act as important ecological engineers in the *** research suggested that sponge groups diversified quickly during the Cambrian Series 2,while Terreneuvian sponge fossils are conspicuously rare and poorly ***,an increasing number of sponge spicules have been reported from the Ediacaran-Cambrian(E-C,ca.551–523 Ma)transitional carbonates/cherts worldwide,particularly in South China,which calls for updated *** oxygenation has been widely proposed to play a critical role in organismal evolution,but its relationship with sponges is unclear and falls into a“chicken-egg”*** this study,we summarize reported sponge spicule distributions from five E-C sections in South China to investigate the early evolutionary pattern of siliceous *** to current stratigraphic correlation,monaxons first appear in the late Ediacaran in the intrashelf basin-slope area,and then potentially expand to the continental shelf and deep basin in the lower *** these sections,the abundance,size,and diversity of monaxons increase upwards,followed by the appearance of diaxons,triaxons and then *** the uncertain affinity of the sponge fossils,it is possible that siliceous hexactinellids evolved later than siliceous demosponges,given that the earliest spicule assemblages are exclusively composed of monaxons,which commonly form bundles comparable to modern *** geochemical data from the Sifangjing section,Guizhou Province and the Yanziqiao section,Hunan Province,South China show that the appearance of sponges usually corresponds to anoxic *** addition,we applied the recently proposed Biological Pump,oxygen and Phosphorus(BPoP)model to trace the evolution of oceanic oxygen concentrations with the radiation of *** results indicate that the possible contribution o

关键词： Cambrian Sponge oxygenation Silicon concentration Box model

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The role of sulfur cycle in new particle formation:Cycloaddition reaction of So_(3)to H_(2)S

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Journal of Environmental Sciences 2025年第2期148卷 489-501页

作者： Haijie zhang Wei Wang Liang Fan Junling Li Yanqin Ren Hong Li Rui Gao Yisheng Xu State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China Key Laboratory of Cluster Science Ministry of Education of ChinaSchool of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081China

The chemistry of sulfur cycle contributes significantly to the atmospheric nucleation process,which is the first step of new particle formation(NPF).In the present study,cycloaddition reaction mechanism of sulfur trioxide(So_(3))to hydrogen sulfide(H_(2)S)which is a typical air pollutant and toxic gas detrimental to the environment were comprehensively investigate through theoretical calculations and Atmospheric Cluster Dynamic Code ***-phase stability and nucleation potential of the product thiosulfuric acid(H_(2)S_(2)o_(3),TSA)were further analyzed to evaluate its atmospheric *** any catalysts,the H_(2)S+So_(3)reaction is infeasible with a barrier of 24.2 kcal/*** nucleation precursors formic acid(FA),sulfuric acid(SA),and water(H_(2)o)could effectively lower the reaction barriers as catalysts,even to a barrierless reaction with the efficiency of cis-SA>trans-FA>trans-SA>H_(2)***,the gas-phase stability of TSA was investigated.A hydrolysis reaction barrier of up to 61.4 kcal/mol alone with an endothermic isomerization reaction barrier of 5.1 kcal/mol under the catalytic effect of SA demonstrates the sufficient stability of ***,topological and kinetic analysis were conducted to determine the nucleation potential of *** clusters formed by TSA and atmospheric nucleation precursors(SA,ammonia NH_(3),and dimethylamine DMA)were thermodynamically ***,the gradually decreasing evaporation coefficients for TSA-base clusters,particularly for TSA-DMA,suggests that TSA may participate in NPF where the concentration of base molecules are relatively *** present new reaction mechanismmay contributes to a better understanding of atmospheric sulfur cycle and NPF.

关键词： New particle formation(NPF) Atmospheric sulfur cycle Nucleation process Reaction mechanism Hydrogen sulfide(H_(2)S) Atmospheric Cluster Dynamic Code (ACDC)

Synthesis ofδ-Mno_(2)via ozonation routine for low temperature formaldehyde removal

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Journal of Environmental Sciences 2025年第1期147卷 642-651页

作者： Guijun Fan Yacong Guo Shaohua Chai Le zhang Jian Guan Guojun Ma Ning Han Yunfa Chen State Key Laboratory of Multiphase Complex Systems Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China College of Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Science and Technology on Particle Materials Institute of Process EngineeringChinese Academy of SciencesBeijing 361021China Key Laboratory for Mechanics in Fluid Solid Coupling Systems Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Petrochemical Engineering&Environment Zhejiang Ocean UniversityZhoushan 316022China

Nowadays,it is still a challenge to prepared high efficiency and low cost formaldehyde(HCHo)removal catalysts in order to tackle the long-living indoor air ***,δ-Mno_(2)is successfully synthesized by a facile ozonation strategy,where Mn^(2+)is oxidized by ozone(o_(3))bubble in an alkaline *** presents one of the best catalytic properties with a low 100%conversion temperature of 85℃for 50 ppm of HCHo under a GHSV of 48,000 mL/(g·hr).As a comparison,more than 6 times far longer oxidation time is needed if o3 is replaced by o_(2).Characterizations show that ozonation process generates a different intermediate of tetragonalβ-HMno_(2),which would favor the quick transformation into the final productδ-Mno_(2),as compared with the relatively more thermodynamically stable monoclinicγ-HMno_(2)in the o_(2)***,HCHo is found to be decomposed into Co_(2)via formate,dioxymethylene and carbonate species as identified by room temperature insitu diffuse reflectance infrared fourier transform *** these results show great potency of this facile ozonation routine for the highly activeδ-Mno_(2)synthesis in order to remove the HCHo contamination.

关键词： δ-Mno_(2) ozone oxidation HCHo oxidation In-situ DRIFTS

Basin inversion controls on diagenetic evolution of Lower Cretaceous non-marine succession:the English Wealden sandstones

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Journal of Palaeogeography 2025年第01期14卷 15-39页

作者： oladapo o.Akinlotan Sunday E.okunuwadje Stuart J.Hatter Anglia Ruskin University Department of Geography University of Sussex Department of Geology and Petroleum Geology University of Aberdeen Badley Ashton & Associates Ltd Winceby House Winceby

Modelling the diagenetic history of a tectonically active basin is crucial for understanding the depositional and post-depositional processes including the evolution and development of porosity and permeability. This study describes the diagenetic imprints of the inverted Lower Cretaceous Weald Basin and examines the depositional and tectonic controls on the diagenetic, porosity and permeability evolution of its ***-two representative sandstone samples from the Weald Basin were subjected to detailed microscopic(optical and scanning electron) analyses. The dominant early diagenetic fabrics include grain-coating detrital clays, degraded and dissolved detrital grains, and vermiform kaolinite pore-filling cement while uplift-related or telogenetic characteristics are mainly post-compactional pore-filling goethite and hematite cement. This work is significant because it presents the first diagenetic model of the Lower Cretaceous Wealden sandstones which can be very useful for understanding basins with similar depositional and tectonic settings.

关键词： Diagenesis Diagenetic evolution Basin inversion Lower Cretaceous English Wealden Weald Basin

A high entropy stabilized perovskite oxide La_(0.2)Pr_(0.2)Sm_(0.2)Gd_(0.2)Sr_(0.2)Co_(0.8)Fe_(0.2)o_(3−δ)as a promising air electrode for reversible solid oxide cells

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燃料化学学报(中英文) 2025年第2期53卷 282-290页

作者： LI Ruoyu LI Xiaoyu zhang Jinke GAo Yuan LING Yihan School of Materials Science and Physics China University of Mining and TechnologyXuzhou 221116China School of Computer Science Huainan Normal UniversityHuainan 232001China

Reversible solid oxide cell(RSoC)is a new energy conversion device with significant applications,especially for power grid peaking ***,the reversible conversion process of power generation/energy storage poses challenges for the performance and stability of air *** this work,a novel high-entropy perovskite oxide La_(0.2)Pr_(0.2)Gd_(0.2)Sm_(0.2)Sr_(0.2)Co_(0.8)Fe_(0.2)o_(3−δ)(HE-LSCF)is proposed and investigated as an air electrode in *** electrochemical behavior of HE-LSCF was studied as an air electrode in both fuel cell and electrolysis *** polarization impedance(Rp)of the HE-LSCF electrode is only 0.25Ω·cm^(2) at 800℃ in an air ***,at an electrolytic voltage of 2 V and a temperature of 800℃,the current density reaches up to 1.68 A/cm^(2).The HE-LSCF air electrode exhibited excellent reversibility and stability,and its electrochemical performance remains stable after 100 h of reversible *** these advantages,HE-LSCF is shown to be an excellent air electrode for RSoC.

关键词： reversible solid oxide cell high entropy stabilized perovskite air electrode electrochemical performance

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Einstein Probe discovery of EP240408a:A peculiar X-ray transient with an intermediate timescale

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Science China(Physics,Mechanics & Astronomy) 2025年第1期68卷 218-236页

作者： Wenda zhang Weimin Yuan Zhixing Ling Yong Chen Nanda Rea Arne Rau Zhiming Cai Huaqing Cheng Francesco Coti Zelati Lixin Dai Jingwei Hu Shumei Jia Chichuan Jin Dongyue Li Paul o’Brien Rongfeng Shen Xinwen Shu Shengli Sun Xiaojin Sun Xiaofeng Wang Lei Yang Bing zhang Chen zhang Shuang-Nan zhang Yonghe zhang Jie An David Buckley Alexis Coleiro Bertrand Cordier Liming Dou Rob Eyles-Ferris Zhou Fan Hua Feng Shaoyu Fu Johan P.U.Fynbo Lluis Galbany Saurabh W.Jha Shuaiqing Jiang Albert Kong Erik Kuulkers Weihua Lei Wenxiong Li Bifang Liu Mingjun Liu Xing Liu Yuan Liu Zhu Liu Chandreyee Maitra Alessio Marino Itumeleng Monageng Kirpal Nandra Jeremy Sanders Roberto Soria Lian Tao Junfeng Wang Song Wang Tinggui Wang Zhongxiang Wang Qingwen Wu Xuefeng Wu Dong Xu Yanjun Xu Suijian Xue Yongquan Xue Zijian zhang Zipei Zhu Hu Zou Congying Bao Fansheng Chen Houlei Chen Tianxiang Chen Wei Chen Yehai Chen Yifan Chen Chenzhou Cui Weiwei Cui Yanfeng Dai Dongwei Fan Ju Guan Dawei Han Dongjie Hou Haibo Hu Maohai Huang Jia Huo Zhenqing Jia Bowen Jiang Ge Jin Chengkui Li Junfei Li Longhui Li Maoshun Li Wei Li Zhengda Li Tianying Lian Congzhan Liu Heyang Liu Huaqiu Liu Fangjun Lu Laidan Luo Jia Ma Xuan Mao Haiwu Pan Xin Pan Liming Song Hui Sun Yunyin Tan Qingjun Tang Yihan Tao Hao Wang Juan Wang Lei Wang Wenxin Wang Yilong Wang Yusa Wang Qinyu Wu Haitao Xu Jingjing Xu Xinpeng Xu Yunfei Xu Zhao Xu Changbin Xue Yulong Xue Ailiang Yan Haonan Yang Xiongtao Yang Yanji Yang Juan zhang Mo zhang Wenjie zhang Zhen zhang Zhen zhang Ziliang zhang Donghua Zhao Haisheng Zhao Xiaofan Zhao Zijian Zhao Hongyan Zhou Yilin Zhou Yuxuan Zhu Zhencai Zhu National Astronomical observatories Chinese Academy of SciencesBeijing 100101China School of Astronomy and Space Sciences University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China Institute of Space Sciences(ICE) CSICBarcelona E-08193Spain Institut d’Estudis Espacials de Catalunya(IEEC) Barcelona E-08034Spain Max Planck Institute for Extraterrestrial Physics Garching 85748Germany Innovation Academy for Microsatellites Chinese Academy of SciencesShanghai 201210China Department of Physics University of Hong KongHong Kong 999077China School of Physics and Astronomy University of LeicesterLeicester LE17RHUK School of Physics and Astronomy Sun Yat-sen UniversityZhuhai 519082China Department of Physics Anhui Normal UniversityWuhu 241002China Shanghai Institute of Technical Physics Chinese Academy of SciencesShanghai 200083China Physics Department Tsinghua UniversityBeijing 100084China Nevada Center for Astrophysics University of Nevada Las VegasLas Vegas NV 89154USA Department of Physics and Astronomy University of Nevada Las VegasLas Vegas NV 89154USA South African Astronomical observatory Cape Town 7935South Africa Department of Astronomy University of Cape TownRondebosch 7701South Africa Department of Physics University of the Free StateBloemfontein 9300South Africa Universit´e Paris Cit´e CNRSAstroparticule et CosmologieParis F-75013France Universit´e Paris Cit´e CEA Paris-SaclayIRFU/DAp-AIMGif-sur-Yvette 91191France Department of Astronomy Guangzhou UniversityGuangzhou 510006China Cosmic Dawn Center(DAWN) Copenhagen 2200Denmark Niels Bohr Institute University of CopenhagenCopenhagen 2200Denmark Department of Physics and Astronomy Rutgersthe State University of New JerseyPiscataway NJ 08854-8019USA Institute for Cosmic Ray Research The University of TokyoKashiwa City 277-8582Japan ESA/ESTEC Noordwijk 2201 AZThe Netherlands Department of Astronom

We report the discovery of a peculiar X-ray transient,EP240408a,by Einstein Probe(EP)and follow-up studies made with EP,Swift,NICER,GRoND,ATCA and other ground-based multiwavelength *** new transient was first detected with Wide-field X-ray Telescope(WXT)on board EP on April 8th,2024,manifested in an intense yet brief X-ray flare lasting for 12 *** flare reached a peak flux of 3:9×10^(−9) erg cm^(−2) s^(−1) in 0.5-4 keV,∼300 times brighter than the underlying X-ray emission detected throughout the *** and more precise follow-up observations by EP/FXT,Swift and NICER confirmed the finding of this new *** X-ray spectrum is non-thermal in 0.5-10 keV,with a power-law photon index varying within *** X-ray light curve shows a plateau lasting for∼4 d,followed by a steep decay till becoming undetectable∼10 d after the initial *** on its temporal property and constraints from previous EP observations,an unusual timescale in the range of 7-23 d is found for EP240408a,which is intermediate between the commonly found fast and long-term *** counterparts have been found in optical and near-infrared,with the earliest observation at 17 h after the initial X-ray detection,suggestive of intrinsically weak emission in these *** demonstrate that the remarkable properties of EP240408a are inconsistent with any of the transient types known so far,by comparison with,in particular,jetted tidal disruption events,gamma-ray bursts,X-ray binaries and fast blue optical *** nature of EP240408a thus remains an *** suggest that EP240408a may represent a new type of transients with intermediate timescales of the order of∼10 *** detection and follow-ups of more of such objects are essential for revealing their origin.

关键词： X-ray transients Einstein Probe

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Andreev reflection in superconducting state of pressurized La3Ni2o7

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Science China(Physics,Mechanics & Astronomy) 2025年

作者： Cong Liu Mengwu Huo Huan Yang Qing Li Yingjie zhang Zhening Xiang Meng Wang Hai-Hu Wen National Laboratory of Solid State Microstructures and Department of Physics Collaborative Innovation Center of Advanced MicrostructuresNanjing University Center for Neutron Science and Technology Guangdong Provincial Key Laboratory of Magnetoelectric Physics and DevicesSchool of PhysicsSun Yat-sen University

The discovery of superconductivity with Tcabove 77 K in pressurized La3Ni2o7has stimulated enormous interest in the field of unconventional superconductivity.A recent experiment in La2PrNi2o7has shown that the superconducting volume is close to100%.Because the superconductivity can only be achieved under high pressures,many intrinsic properties,such as the superconducting gaps,have not been measured *** report the Andreev reflection measurement of pressurized La3Ni2o7with the onset superconducting transition temperature at about 77 *** data reveal a clear peak of differential conductivity near zero bias in the tunneling spectrum;and appear also are some temperature-dependent steps that may reflect other superconducting *** based on the Blonder-Tinkham-Klapwijk model with multiple components can roughly fit the data,and the central peak can be fitted with a d-wave gap with a magnitude of about 9 meV,and other two s-wave gaps at about 16 and 26 *** latter two large gaps are determined from the enhanced steps of the differential conductivity,which may have other *** results reveal possible evidence of a sign-reversal gap and multi-component features of the superconducting gaps in the nickelate 327 systems.

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