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Lactonization of dyes promoted by a coordination cage facilitates cavity-induced chromism as ion mobile detector

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Science China Chemistry 2024年第5期67卷 1554-1560页

作者： liangliang zhang yu liang Zhifeng Xiao yuxuan Meng Jinyi Huang Xi Lin Ji Li Hong-Cai Zhou yu Fang Strait Institute of Flexible Electronics(SIFE Future Technologies)Fujian Normal University and Strait Laboratory of Flexible Electronics(SLoFE)Fuzhou 350017China State Key Laboratory of Chemo/Bio-Sensing and Chemometrics College of Chemistry and Chemical EngineeringHunan UniversityChangsha 410082China Department of Chemistry Texas A&M UniversityCollege StationTexas 77842-3012USA State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China Frontiers Science Center for Flexible Electronics(FSCFE) MIIT Key Laboratory of Flexible Electronics(KLoFE)Northwestern Polytechnical UniversityXi’an 710072China

Dye molecules often change colors(so-called “chromism”) according to the environment variation. However, they are rarely induced by a catalytic amount of cavity. Through encapsulation in the cavity of a porous coordination cage(PCC-2), Rhodamine B(1) is transformed from red quinonoid form(1q) into colorless lactone form(1l) in aprotic polar solutions. The μ4-OH groups in the cavity of PCC-2 are shown to stabilize the uncommon zwitterion intermediate(1z), followed by converting to 1l, thus accelerating the equilibrium. The chromism is catalyzed by 0.25 mol% of PCC-2, and the reaction rate is improved by 80,400times. 1@PCC-2 can be further fabricated to a sol-gel that exhibits ion recognition properties. The resulting encapsulation and stabilization of an unconventional intermediate by a catalytic amount of the coordination cage provides fundamental insights into molecular isomerization and has potential use in chemical sensing.

关键词： porous coordination cage Zwitterion intermediate cavity Rhodamine B chromism

The influence of yttrium and manganese additions on the degradation and biocompatibility of magnesium-zinc-based alloys:In vitro and in vivo studies

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Journal of Magnesium and Alloys 2024年第2期12卷 608-624页

作者： Lei Shi Yang Yan Chun-sheng Shao Kun yu Bo zhang liang-jian Chen Third Xiangya Hospital Central South UniversityChangsha 410013China State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China School of Materials Science and Engineering Central South UniversityChangsha 410083China Department of Mechanical Engineering City University of Hong KongHong KongChina

The repair and regeneration of bone defects are highly challenging orthopedic ***,Mg-based implants have gained popularity due to their unique biodegradation and elastic modulus similar to that of human *** aim of our study is to develop a magnesium alloy with a controllable degradation that can closely match bone tissue to help injuries heal in vivo and avoid cytotoxicity caused by a sudden increase in ion *** this study,we prepared and modified Mg-3Zn,Mg-3Zn-1Y,and Mg-2Zn-1Mn by hot extrusion,and used Mg-2.5Y-2.5Nd was as a *** then investigated the effect of additions of Y and Mn on alloys'*** results show that Mn and Y can improve not only compression strength but also corrosion *** alloy Mg-2Zn-1Mn demonstrated good cytocompatibility in vitro,and for this reason we selected it for implantation in *** degraded Mg-2Zn-1Mn implanted a bone defect area did not cause obvious rejection and inflammatory reaction,and the degradation products left no signs of damage to the heart,liver,kidney,or ***,we find that Mg-2Zn-1Mn can promote an osteoinductive response in vivo and the formation of bone regeneration.

关键词： Magnesium alloy Biodegradation Biocompatibility Bone regeneration Bone defect repair

Research on the variation of dielectric properties of oil-paper insulation for power equipment over a wide temperature range

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HIGH VOLTAGE 2024年第3期9卷 648-658页

作者： zhang, Mingze yu, Muhe Zhou, Wen liang, Yilin Lei, Shengjie Shi, yunbo Qu, Limin Harbin Univ Sci & Technol Key Lab Engn Dielect & Its Applicat Minist Educ Harbin Peoples R China Harbin Univ Sci & Technol Sch Measurement & Commun Engn Harbin Peoples R China State Grid Heilongjiang Elect Power Co Ltd Elect Power Res Inst Harbin Peoples R China

The main part of oil-immersed power equipment is oil-paper insulation. At lower ambient temperatures, transformer oil will become viscous. As a result, compared to those at room temperature or operating temperature, the frequency domain dielectric properties of oil-paper insulation at low temperatures are drastically different. For evaluating the insulation condition of electrical equipment, it is essential to accurately determine their dielectric properties. This paper described the FDS test, the DC conductivity test, and the transformer oil viscosity test, which was carried out in a laboratory environment for different ageing of oil-immersed pressboard and transformer oil at 233-373 K. The effects of temperature on the dielectric properties at the competing mechanisms of polarisation and conductivity loss were clarified based on variations of the FDS curves. Considering the viscosity change of ageing transformer oil at low temperatures, the Arrhenius and VFT viscosity equations were used to achieve a fitting calculation in the different temperature zones. Based on the molecular/ion transition model in the force field and electric field, the characterisation relationships between the dynamic viscosity, DC conductivity, and test temperature of transformer oil were established. The limitations of conventional transformer oil equivalent dielectric relaxation models over a wide temperature range were finally clarified by combining the test findings of the DC conductivity over a wide temperature range with observed and simulated calculations. This paper provides an essential theoretical reference when using the FDS test to diagnose the insulation performance of oil-immersed power equipment in extremely cold regions.

关键词： QUANTITATIVE-ANALYSIS ACTIVATION-ENERGY TRANSFORMER OIL AGING CONDITION PRESSBOARD VISCOSITY

Continuous Fe^(3+)releasing enabled complete reconstruction of Ni-based MOF for promoted water oxidation in industrial alkali

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Science China Chemistry 2024年第9期67卷 2949-2957页

作者： Zhaojian Wang Wei zhang Wenzhong Huang Ruohan yu Changliang Chen Liqiang Mai liang Zhou State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China Sanya Science and Education Innovation Park Wuhan University of TechnologySanya 572000China Hubei Longzhong Laboratory Wuhan University of Technology(Xiangyang Demonstration Zone)Xiangyang 441000China

Most oxygen evolution reaction(OER)electrocatalysts show poor stability under industrial alkaline conditions(20–30 wt.%KOH).Therefore,it is essential to develop stable,efficient,and low-cost OER catalysts for industrial water ***,we present a straightforward approach for the complete electrochemical reconstruction of Ni-BDC,a Ni-based metal-organic framework,for *** method involves the continuous release of Fe^(3+)from Fe foam counter electrode in a high-concentration(6.0 M,25 wt.%)KOH *** continuously Fe^(3+)releasing not only realizes in situ Fe^(3+)doping,but also introduces abundant defects in the obtained catalyst during cyclic voltammetry activation,thereby accelerating the electrochemical *** reconstructed OER catalyst(Fe-doped nickel hydroxide/oxyhydroxide nanosheets supported on Ni foam,Fe-NiO_(x)(OH)y/NF)manifests a low overpotential of 217 mV at 10 mA cm^(-2)and 263 m V at 100 m A cm^(-2)in 1.0 M ***,the Fe-NiO_(x)(OH)_(y)/NF also demonstrates high stability in 30 wt.%*** strategy of regulating the electrochemical reconstruction process sheds light on the construction of stable and efficient OER catalysts for industrial water electrolysis.

关键词： oxygen evolution reaction industrial alkaline conditions metal-organic framework complete reconstruction

Sourcing the merits of 3D integrated air cathodes for highperformance Zn-air batteries by bubble pump consumption chronoamperometry

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Nano Research 2024年第8期17卷 6951-6959页

作者： Mengxuan Li Linfeng yu Hai Liu Chuanyi zhang Jiazhan Li liang Luo Xiaoming Sun State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China

Zn-air batteries(ZABs)as a potential energy conversion system suffer from low power density(typically≤200 mW·cm^(−2)).Recently,three-dimensional(3D)integrated air cathodes have demonstrated promising performance over traditional twodimensional(2D)plane ones,which is ascribed to enriched active sites and enhanced diffusion,but without experimental ***,we applied a bubble pump consumption chronoamperometry(BPCC)method to quantitatively identify the gas diffusion coefficient(D)and effective catalytic sites density(ρEC)of the integrated air cathodes for ***,the D andρEC values can instruct consequent optimization on the growth of Co embedded N-doped carbon nanotubes(CoNCNTs)on carbon fiber paper(CFP)and aerophilicity tuning,giving 4 times D and 1.3 timesρEC over the conventional 2D Pt/C-CFP *** a result,using the CoNCNTs with half-wave potential of merely 0.78 V ***(Pt/C:0.89 V ***),the superaerophilic CoNCNTs-CFP cathode-based ZABs exhibited a superior peak power density of 245 mW·cm^(−2) over traditional 2D Pt/C-CFP counterparts,breaking the threshold of 200 mW·cm^(−2).This work reveals the intrinsic feature of the 3D integrated air cathodes by yielding exact D andρEC values,and demonstrates the feasibility of BPCC method for the optimization of integrated electrodes,bypassing trial-and-error strategy.

关键词： Zn-air batteries three-dimensional(3D)integrated air cathodes superaerophilic gas diffusion coefficient effective catalytic sites density

Strain-enhanced polarization sensitivity inβ-Ga_(2)O_(3)photodetector

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Science China(Physics,Mechanics & Astronomy) 2024年第4期67卷 126-137页

作者： Yonghui zhang Huili liang Fei Xing Qiqian Gao yu Feng yuping Sun Zengxia Mei School of Physics and Optoelectronic Engineering Shandong University of TechnologyZibo 255000China Songshan Lake Materials Laboratory Dongguan 523808China Institute of Physics Chinese Academy of SciencesBeijing 100190China

Polarization-sensitive photodetection and imaging have great application value in fields such as polarization division multiplexing optical communication,remote sensing,near-field imaging and military *** a high polarization ratio has always been the research hotspot in polarization-sensitive *** this paper,we report a compression strain enhanced polarization ratio inβ-gallium oxide(β-Ga_(2)O_(3))single crystal flake.A rigorous crystallographic analysis confirmed its high crystalline quality and ***-resolved polarization Raman spectroscopy(ARPRS)was adopted to study the anisotropy of its optical *** ARPRS measurements and theoretical calculation consistently demonstrate the strong optical anisotropy in the high-qualityβ-Ga_(2)O_(3)flake.A polarization ratio of 0.96 was obtained in the flatβ-Ga_(2)O_(3)***,mechanical strain of±0.7%was introduced intoβ-Ga_(2)O_(3).An increased polarization ratio of 0.98 was achieved in the case of 0.7%compression strain,which is,to the best of our knowledge,the highest value for UVC polarization-sensitive *** corresponds to an improved polarization rejection ratio of *** work proposed a new path towards improving polarization sensitivity by applying strain engineering in the active material.

关键词： gallium oxide polarization photodetector anisotropy strain

Encoding and display technologies for combinatorial libraries in drug discovery:The coming of age from biology to therapy

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Acta Pharmaceutica Sinica B 2024年第8期14卷 3362-3384页

作者： yu Fan Ruibing Feng Xinya zhang Zhen-liang Wang Feng Xiong Shuihua zhang zhang-Feng Zhong Hua yu Qing-Wen zhang zhang zhang Yitao Wang Guodong Li Macao Centre for Research and Development in Chinese Medicine State Key Laboratory of Quality Research in Chinese MedicineInstitute of Chinese Medical SciencesUniversity of MacaoMacao SAR 999078China State Key Laboratory of Quality Research in Chinese Medicine Institute of Chinese Medical SciencesUniversity of MacaoMacao SAR 999078China International Cooperative Laboratory of Traditional Chinese Medicine Modernization and Innovative Drug Development Ministry of Education(MoE)of People’s Republic of ChinaCollege of PharmacyJinan UniversityGuangzhou 510632China Zhuhai UM Science and Technology Research Institute Zhuhai 519031China Department of Pharmacy Guangzhou Red Cross HospitalFaculty of Medical ScienceJinan UniversityGuangzhou 510632China Geriatric Medicine First People’s Hospital of XinXiang and the Fifth Affiliated Hospital of Xinxiang Medical CollegeXinxiang 453100China Shenzhen Innovation Center for Small Molecule Drug Discovery Co. Ltd.Shenzhen 518000China

Drug discovery is a sophisticated process that incorporates scientific innovations and cuttingedge *** to traditional bioactivity-based screening methods,encoding and display technologies for combinatorial libraries have recently advanced from proof-of-principle experiments to promising tools for pharmaceutical hit discovery due to their high screening efficiency,throughput,and resource *** review systematically summarizes the development history,typology,and prospective applications of encoding and displayed technologies,including phage display,ribosomal display,mRNA display,yeast cell display,one-bead one-compound,DNA-encoded,peptide nucleic acidencoded,and new peptide-encoded technologies,and examples of preclinical and clinical *** discuss the progress of novel targeted therapeutic agents,covering a spectrum from small-molecule inhibitors and nonpeptidic macrocycles to linear,monocyclic,and bicyclic peptides,in addition to *** also address the pending challenges and future prospects of drug discovery,including the size of screening libraries,advantages and disadvantages of the technology,clinical translational potential,and market *** review is intended to establish a comprehensive high-throughput drug discovery strategy for scientific researchers and clinical drug developers.

关键词： Drug screening Phage display DNA-encoded chemical libraries Peptide-encoded chemical libraries Clinical drugs

A real-time calibration method based on time-to-digital converter for accelerator timing system

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Nuclear Science and Techniques 2024年第9期35卷 127-140页

作者： Qi-Hao Duan liang Ge Yan-Hao Jia Jie-yu Zhu Wei zhang Institute of modern physics Chinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China

The high-intensity heavy-ion accelerator facility(HIAF)is a scientific research facility complex composed of multiple cas-cade accelerators of different types,which pose a scheduling problem for devices distributed over a certain range of 2 km,involving over a hundred *** white rabbit,a technology-enhancing Gigabit Ethernet,has shown the capability of scheduling distributed timing devices but still faces the challenge of obtaining real-time synchronization calibration param-eters with high *** study presents a calibration system based on a time-to-digital converter implemented on an ARM-based System-on-Chip(SoC).The system consists of four multi-sample delay lines,a bubble-proof encoder,an edge controller for managing data from different channels,and a highly effective calibration module that benefits from the SoC *** performance was evaluated with an average RMS precision of 5.51 ps by measuring the time intervals from 0 to 24,000 ps with 120,000 data for every *** design presented in this study refines the calibration precision of the HIAF timing *** eliminates the errors caused by manual calibration without efficiency loss and provides data support for fault *** can also be easily tailored or ported to other devices for specific applications and provides more space for developing timing systems for particle accelerators,such as white rabbits on HIAF.

关键词： HIAF White rabbit Calibration system Time-to-digital converter(TDC)

1981─2020年河北省基于SPEI的干旱变化特征分析

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江西农业学报 2024年第1期36卷 95-101页

作者：魏丽欣赵春雷张良玉高万泉王欢保定市气象局河北保定071000 保定市生态气象智能监测与服务重点实验室河北保定071000 河北省气象科学研究所河北石家庄050021 河北省气象与生态环境重点实验室河北石家庄050021

基于1981─2020年河北省138个气象站点的逐月降水和气温数据,计算了不同时间尺度的标准化降水蒸散指数(SPEI),并利用Sen趋势分析、Mann-Kendall检验及反距离权重插值等方法,分析了河北省近40年干旱的时空变化特征。结果表明:1981─2020... 详细信息

基于1981─2020年河北省138个气象站点的逐月降水和气温数据,计算了不同时间尺度的标准化降水蒸散指数(SPEI),并利用Sen趋势分析、Mann-Kendall检验及反距离权重插值等方法,分析了河北省近40年干旱的时空变化特征。结果表明:1981─2020年河北省月、季、年尺度的SPEI值均呈下降趋势,且随着时间尺度的加大,发生干旱的频率下降,持续时间延长。春季、夏季和年际的SPEI值均呈下降趋势,秋季和冬季的SPEI值均呈上升趋势。2016─2020、2011─2020年春季和冬季均处于变湿状态,夏季和秋季均处于变干状态。2011─2020年河北省大部分地区呈干旱状态。不同年代季尺度和年尺度的干旱频率整体上呈增加趋势。河北省发生的轻、中度干旱事件多于重度以上干旱事件。20世纪90年代、21世纪10年代SPEI值减少区域的占比大。20世纪80年代、21世纪00年代SPEI值增加区域的占比大。

关键词：河北省 SPEI指数干旱变化特征