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NHC-mediated photocatalytic para-selective C–H acylation of aryl alcohols: regioselectivity control via remote radical spiro cyclization

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Science China Chemistry 2025年

作者： tinglei zhang Lala Wang Xiaolin Peng tianhui Liao Dongmei Chen ting tu Donghan Liu Ziye Cheng Shiqing Huang Shi-Chao Ren Xinglong zhang Yonggui Robin Chi State Key Laboratory of Green Pesticide Key Laboratory of Green Pesticide and Agricultural Bioengineering Ministry of Education Guizhou University Qiannan Medical College for Nationalities School of Chemistry Chemical Engineering and Biotechnology Nanyang Technological University Department of Chemistry The Chinese University of Hong Kong Institute of High Performance Computing Agency for Science Technology and Research

Friedel-Crafts reaction and transition-metal catalysis represent primary methodologies for arene acylation; however, suffer from certain limitations, such as electronic effect-dependent reactivity, regioselectivity issues, the necessity of directing group, and relatively exceptionally limited exploration in meta-and para-acylations. N-heterocyclic carbene(NHC) catalysis has recently emerged as a promising alternative strategy for arene acylation, offering distinct regioselectivity profiles that are challenging to achieve through known methods. Herein, an NHC-mediated photo-catalytic para-selective C–H acylation of aryl alcohols is disclosed. the reaction employs a remote radical-induced temporary spiro cyclization strategy, proceeding via tandem radical dearomatization, radical acylation, rearomatization processes. Combined experimental and computational mechanistic studies support the proposed reaction pathway and observe an exclusive para-selectivity regardless of the nature of the substituents on the substrates. Despite the less satisfactory yields, the current method exhibits non-electronic nature-based reactivity and regioselectivity, enabling quick access to acylated arenes that are difficult or impossible for reported methods.

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Gas-Solid Flow,Combustion Characteristics,and Gas Emissions in a 75 t/h CFB Boiler Based on the CPFD Method

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journal of thermal Science 2025年第1期34卷 323-336页

作者： HUANG Xiankun BAI zhang ZHU Xiaoli WANG Shuoshuo MU Lin GONG Liang College of New Energy China University of Petroleum (East China) Key Laboratory of Ocean Energy Utilization and Energy Conservation of Ministry of Education School of Energy and Power EngineeringDalian University of Technology

A 3D simulation using Computational Particle Fluid Dynamics（CPFD） methods was used to calculate coal combustion in a 75 t/h industrial-scale circulating fluidized bed（CFB） *** characteristics,gas-solid flow characteristics,and gaseous pollutant emissions of CFB boilers from combustion ignition to stable operation were systematically evaluated in this *** show that the temperature distribution is relatively uniform throughout the *** the combustion process unfolds within the boiler,the gas composition curve strikingly portrays the inverse correlation between CO2and *** the combustion reaction progresses,it becomes evident that the concentration of CO2progressively increases,while the concentration of O2concurrently *** inverse relationship underscores the fundamental combustion reaction,where carbon-based fuels react with oxygen to produce carbon dioxide and release ***,a comprehensive analysis has revealed that,from ignition to stable combustion,both nitric oxide（NO） and sulfur dioxide（SO2） emissions exhibit a declining *** reduction in pollutant generation is attributed to the improvement in combustion *** complete combustion leads to lower levels of unburned hydrocarbons,which are prone to NO ***,the sulfur content in the fuel is more efficiently oxidized to sulfur trioxide（SO3） or bound in sulfates,reducing *** steady state in the simulation,the SO2mass flow rate varies significantly with the furnace height,gradually increasing from 0.07 kg·s-1at 4 m at the bottom of the furnace to a peak of 0.078 kg·s-1at 8 m in the center,and then decreasing to 0.06 kg·s-1at 20m at the top of the furnace.

关键词： Sulfur dioxide

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tHE IMPROVEMENt IN FRICtION AND WEAR RESIStANCE FORta and ta+C IMPLANtED Cr12 StEEL

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Acta Metallurgica Sinica(English Letters) 1998年第2期11卷 137-140页

作者： j.H.Yang t.H.zhang Nantong Inst of technology Nantong China

ta and C ions extracted from a MEVVA ion source were implanted into Cr12 steel, with an implantation dose of (1-5)ｘ1017cm-2, extraction acceleration 42kV, and average ion beam flux about 20-50μA·cm-2. Rutherford backscattering spectrum (RBS) was used to measure the surface composition after ta and ta+C implantation. Analysis of phase formed by ta and C implantation was carried out by X-ray diffraction analysis (XRD). Experiment results showed that the wear rate of the implanted layer dropped 40% for ta ion implantation and by a factor of 2.7 for ta+C dual ion implantation. ta+C dual ion implantation was found to reduce the friction coefficient of Cr12 steel. the wear mechanisms of the implanted layer were discussed.

关键词： wear resistance Cr12 steel ion implantation

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Modulation of the octahedral structure and potential superconductivity of La3Ni2O7 through strain engineering

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Science China(Physics,Mechanics & Astronomy) 2025年

作者： Zihao Huo Zhihui Luo Peng zhang Aiqin Yang Zhengtao Liu Xiangru tao Zihan zhang Shumin Guo Qiwen jiang Wenxuan Chen Dao-Xin Yao Defang Duan tian Cui Key Laboratory of Material Simulation Methods & Software of Ministry of Education State Key Laboratory of Superhard Materials College of Physics Jilin University Center for Neutron Science and technology Guangdong Provincial Key Laboratory of Magnetoelectric Physics and Devices State Key Laboratory of Optoelectronic Materials and Technologies School of Physics Sun Yat-sen University MOE Key Laboratory for Non-equilibrium Synthesis and Modulation of Condensed Matter Shaanxi Province Key Laboratory of Advanced Functional Materials and Mesoscopic Physics School of Physics Xi'an Jiaotong University Institute of High Pressure Physics School of Physical Science and Technology Ningbo University

the recent transport measurements of La3Ni2O7uncovered a“right-triangle”shape of the superconducting dome in the pressure-temperature （P-t） phase *** by this,we perform theoretical first-principles studies of La3Ni2O7with the pressure ranging from 0 to 100 ***,we reveal a pressure dependence of the Ni-d2zelectron density at the Fermi energy (nE Fz) that highly coincides with such *** this basis,we further explore the electronic structure under uniaxial *** tracking the stress response of nE Fz,we propose that superconductivity can be achieved by applying only～2 GPa of compression along the c *** idea is further exemplified from the perspectives of lattice distortion,band structure,Fermi surface and superconducting phase *** also discuss the possible charge modulation under the stress and provide an insight into the relation between nE Fzand the superconducting tcin *** study provides new routes to the search of high-tcsuperconductors in future experiments.

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Inhibition of the NLRP3 inflammasome attenuates spiral ganglion neuron degeneration in aminoglycoside-induced hearing loss

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Neural Regeneration Research 2025年第10期20卷 3025-3039页

作者： jia Fang Zhuangzhuang Li Pengjun Wang Xiaoxu zhang Song Mao Yini Li Dongzhen Yu Xiaoyan Li Yazhi Xing Haibo Shi Shankai Yin Department of Otolaryngology Head and Neck Surgery Shanghai Sixth People’s Hospital Affiliated to Shanghai Jiao Tong University School of MedicineOtolaryngology Institute of Shanghai Jiao Tong UniversityShanghai Key Laboratory of Sleep Disordered BreathingShanghaiChina Department of Otorhinolaryngology-Head and Neck Surgery Shanghai Children’s HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghaiChina

Aminoglycosides are a widely used class of antibacterials renowned for their effectiveness and broad antimicrobial ***,their use leads to irreversible hearing damage by causing apoptosis of hair cells as their direct *** addition,the hearing damage caused by aminoglycosides involves damage of spiral ganglion neurons upon *** investigate the mechanisms underlying spiral ganglion neuron degeneration induced by aminoglycosides,we used a C57BL/6j mouse model treated with *** found that the mice exhibited auditory deficits following the acute loss of outer hair *** ganglion neurons displayed hallmarks of pyroptosis and exhibited progressive degeneration over *** profiling of these neurons showed significant upregulation of genes associated with inflammation and immune response,particularly those related to the NLRP3 *** of the canonical pyroptotic pathway in spiral ganglion neurons was observed,accompanied by infiltration of macrophages and the release of proinflammatory *** intervention targeting NLRP3 using Mcc950 and genetic intervention using NLRP3 knockout ameliorated spiral ganglion neuron degeneration in the injury *** findings suggest that NLRP3 inflammasome-mediated pyroptosis plays a role in aminoglycoside-induced spiral ganglion neuron *** of this pathway may offer a potential therapeutic strategy for treating sensorineural hearing loss by reducing spiral ganglion neuron degeneration.

关键词： degeneration hearing loss macrophages Mcc950 neuroinflammation NLRP3 inflammasome ototoxicity pyroptosis sensorineural hearing loss spiral ganglion neuron

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Remarkably high fracture toughness of HfNbtatiZr refractory high-entropy alloy

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journal of Materials Science & technology 2022年第28期123卷 70-77页

作者： X.j.Fan R.t.Qu Z.F.zhang Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Nano Science and technology Institute University of Science and Technology of ChinaSuzhou 215132China

High-entropy alloys(HEAs)with face-centered cubic(FCC)phase such as CoCrFeMnNi or CoCrNi generally exhibit ultra-high fracture toughness but relatively low *** contrast,body-centered cubic(BCC)HEAs often display higher strengths,but the few reports on fracture toughness measurement demonstrate low toughness *** we show that the BCC HfNbtatiZr refractory HEA,which possesses a combination of high strength,good tensile ductility and excellent high-temperature properties,also exhibits a remarkably high fracture *** using the"single specimen"compliance method for j-integral measurement according to the AStM E1820–17 standard,its fracture toughness K_(jIC)was experimentally determined to be 210 MPa m^(1/2),which renders this HEA among the toughest metallic *** excellent damage tolerance makes the HEA promising for applications as high-temperature structural materials such as in aerospace field.

关键词： High-entropy alloys BCC structure Fracture toughness j-integral

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Research on Euclidean Algorithm and Reection on Its teaching

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应用数学 2025年第1期38卷 308-310页

作者： zhang Shaohua School of Mathematics and Statistics Yangtze Normal UniversityChongqing 408102China

In this paper,we prove that Euclid's algorithm,Bezout's equation and Divi-sion algorithm are equivalent to each *** result shows that Euclid has preliminarily established the theory of divisibility and the greatest co... 详细信息

关键词： Euclid's algorithm Division algorithm Bezout's equation

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High-precision magnetic field measurement system based on a coherent population trapping magnetometer onboard the SAtech-01 satellite

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Science China technological Sciences 2025年

作者： Hongbo XUE Wei SONG Haoran ZHAO Yiteng zhang Shanzhi YE jindong WANG Ran tAO Peng SANG Keli CHEN Xingzi BI Bingjun CHENG Bin ZHOU Yongliang XUE Yingying tANG Liu LIU jinsong LI Xiaocheng ZHU Baoquan LI jinguo LIU Wen CHEN Xiaofeng zhang Yonghe zhang Lei LI State Key Laboratory of Space Weather National Space Science Center Chinese Academy of Sciences Key Laboratory of Solar Activity and Space Weather National Space Science Center Chinese Academy of Sciences Key Laboratory of Electronics and Information technology for Space Systems National Space Science Center Chinese Academy of Sciences State Key Laboratory of Robotics Shenyang Institute of Automation Chinese Academy of Sciences Innovation Academy for Microsatellites Chinese Academy of Sciences

On july 27, 2022, a high-precision system for measuring the magnetic field based on a coherent population trapping magnetometer（referred to as the CPt system） was launched onboard the Space Advanced technology demonstration satellite（SAtech-01） by a ZK-1A rocket. the payload comprises a scalar coherent population trapping magnetometer（CPtM）, triaxial anisotropic magnetoresistance magnetometer（AMRM）, and nano star tracker mounted on a non-magnetic telescopic tubular mast. this configuration enables synchronized measurement of scalar and vector geomagnetic fields, as well as the attitude,making the payload with its compact sensors suitable for applications on miniature satellite platforms. On November 7, 2022,the novel telescopic tubular mast was deployed in orbit, extending to a length of 5.28 m. the CPtM, an absolute scalar magnetometer with an omnidirectional sensor, is the first China-developed quantum/atomic magnetometer successfully operating in space. In orbit, the CPtM has sensitivity of ～10 pt/Hz1/2and can automatically operate under complex magnetic field variations. the difference between the scalar fields obtained using the CPtM and CHAOS model has a mean deviation of–3.73 n t and a standard deviation of 26.11 nt（1σ）, without on-orbit calibration or correction. the miniaturized AMRM has a sensitivity of ～0.3 n t/Hz1/2and maintains stable and reliable operation in orbit. the low-power and miniaturized nano star tracker has a measurement uncertainty of 14.23″（1σ） in orbit. the mission has realized the on-orbit technical verification of the integrated and synchronized detection of the vector magnetic field and attitude and fully validated the system's performance,automation level, and reliability.

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A surface engineering strategy for the stabilization of zinc metal anodes with montmorillonite layers toward long-life rechargeable aqueous zinc ion batteries

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journal of Energy Chemistry 2025年第1期100卷 94-105页

作者： Wenbo Wang Ruifeng Xu Xu zhang Peiyu Wang Bao Yang Bingjun Yang juan Yang Kailimai Su Pengjun Ma Yanan Deng Xianfeng Fan Wanjun Chen Key Laboratory for Electronic Materials College of Electrical Engineering Northwest Minzu University Resource Chemistry and Energy Materials Research Center State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical Physics Chinese Academy of Sciences University of Chinese Academy of Sciences Institute for Materials and Processes School of Engineering University of Edinburgh

Rechargeable aqueous zinc-ion batteries （AZIBs） exhibit appreciable potential in the domain of electrochemical energy ***,there are serious challenges for AZIBs,for instance zinc dendrite growth,hydrogen evolution reaction （HER）,and corrosion side ***,we propose a surface engineering modification strategy for coating the montmorillonite （MMt） layer onto the surface of the Zn anode to tackle these issues,thereby achieving high cycling stability for rechargeable *** results reveal that the MMt layer on the surface of the Zn anode is able to provide ordered zincophilic channels for zinc ions migration,facilitating the reaction kinetics of zinc *** functional theory（DFt） calculations and water contact angle （CA） tests prove that MMt@Zn anode exhibits superior adsorption capacity for Zn2+and better hydrophobicity than the bare Zn anode,thereby achieving excellent cycling ***,the MMt@Zn||MMt@Zn symmetric cell holds the stable cycling over 5600 h at 0.5 mA cm-2and 0.125 m A h cm-2,even exceeding 1800 h long cycling under harsh conditions of 5 m A cm-2and 1.25 m A h *** MMt@Zn||V2O5full cell reaches over 3000 cycles at 2 A g-1with excellent rate ***,this surface engineering modification strategy for enhancing the electrochemical performance of AZIBs represents a promising application.

关键词： Hydrogen evolution reaction

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Dual‑Donor‑Induced Crystallinity Modulation Enables 19.23% Efficiency Organic Solar Cells

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Nano-Micro Letters 2025年第3期17卷 376-388页

作者： Anhai Liang Yuqing Sun Sein Chung jiyeong Shin Kangbo Sun Chaofeng Zhu jingjing Zhao Zhenmin Zhao Yufei Zhong Guangye zhang Kilwon Cho Zhipeng Kan Center On Nanoenergy Research Institute of Science and Technology for Carbon Peak&NeutralitySchool of Physical Science&TechnologyGuangxi UniversityNanning 530004People’s Republic of China Department of Chemical Engineering Pohang University of Science and TechnologyPohang 37673South Korea College of New Materials and New Energies Shenzhen Technology UniversityShenzhen 518118People’s Republic of China Zhejiang Engineering Research Center for Fabrication and Application of Advanced Photovoltaic Materials School of Materials Science and EngineeringNingboTech UniversityNingbo 315100People’s Republic of China State Key Laboratory of Featured Metal Materials and Life-Cycle Safety for Composite Structures Nanning 530004People’s Republic of China

trap-assisted charge recombination is one of the primary limitationsof restricting the performance of organic solar cells. However, effectivelyreducing the presence of traps in the photoactive layer remains ***, wide bandgap polymer donor PtzBI-dF is demonstrated as an effectivemodulator for enhancing the crystallinity of the bulk heterojunction active layerscomposed of D18 derivatives blended with Y6, leading to dense and orderedmolecular packings, and thus, improves photoluminescence quenching *** a result, the photovoltaic devices exhibit reduced trap-assisted charge recombinationlosses, achieving an optimized power conversion efficiency of over 19%.Besides the efficiency enhancement, the devices comprised of PtzBI-dF as athird component simultaneously attain decreased current leakage, improved chargecarrier mobilities, and suppressed bimolecular charge recombination, leading toreduced energy losses. the advanced crystalline structures induced by PtzBI-dFand its characteristics, such as well-aligned energy level, and complementaryabsorption spectra, are ascribed to the promising performance *** findings suggest that donor phase engineering is a feasible approach to tuning the molecular packings in the active layer, providingguidelines for designing effective morphology modulators for high-performance organic solar cells.

关键词： trap-assisted charge recombination Photoluminescence Miscibility Current leakage Power conversion efficiency

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