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高能物理与核物理 1999年第12期23卷 1148-1151页

作者：李祖豪何景棠吕雨生陈端保卞建国朱国义唐孝威中国科学院高能物理研究所北京100039

报道对钨酸铅晶体作低剂量辐照损伤研究的实验装置、方法、和结果．利用北京计量科学研究院的小型６０Ｃｏ放射源对４块钨酸铅晶体作了辐照损伤的实验，发现光产额随辐照剂量的增加呈现指数衰减，最后趋于饱和．

关键词：钨酸铅晶体光产额辐照损伤电磁量能器

Anion competition for li^(+)solvated coordination environments in poly(1,3 dioxolane)electrolyte to enable high-voltage lithium metal solid-state batteries

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Journal of Energy Chemistry 2024年第9期96卷 633-641页

作者： Qiujun Wang Yanqiang Ma Xiaomeng Jia Di Zhang Zhaojin li Huilan Sun Qujiang Sun Bo Wang li-Zhen Fan Hebei Key Laboratory of Flexible Functional Materials School of Materials Science and EngineeringHebei University of Science and TechnologyShijiazhuang 050000HebeiChina Beijing Advanced Innovation Center for Materials Genome Engineering Institute of Advanced Materials and TechnologyUniversity of Science and Technology BeijingBeijing 100083China

Gel-based polymer electrolytes are limited by the polarity of the residual solvent,which restricts the coupling-breaking behaviour during li^(+)conduction,resulting in the li^(+)transport kinetics being greatly ***,we designed anion competitive gel polymer electrolyte(ACPE)by introducing lithium difluoro(oxalato)borate(liDFOB)anion into the 1,3-dioxolane(DOL)in situ polymerisation *** enhances the ionic dipole interaction between li^(+)and the solvent molecules and synergizes with li^(+)across the solvation site of the polymer ethylene oxide(EO)unit,combination that greatly improves the li^(+)transport *** a result,ACPE exhibits 1.12 mS cm^(−1)ionic conductivity and 0.75 li^(+)transfer number at room ***,this intra-polymer solvation sheath allows preferential desolvation of DFOB−,which contributes to the formation of kinetically stable anion-derived interphase and effectively mitigates side *** results demonstrate that the assembled li||NCM622 solid-state battery exhibits lifespan of over 300 cycles with average Coulombic efficiency of 98.8%and capacity retention of 80.3%.This study introduces a novel approach for ion migration and interface design,paving the way for high-safety and high-energy-density batteries.

关键词： li-metal batteries Poly(1,3-dioxolane) In situ polymerization Solid-state polymer electrolytes Anion competition

Dual-single-atoms of Pt-Co boost sulfur redox kinetics for ultrafast li-S batteries

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Carbon Energy 2024年第3期6卷 53-63页

作者： Hanyan Wu Xuejie Gao Xinyang Chen Weihan li Junjie li Lei Zhang Yang Zhao Ming Jiang Runcang Sun Xueliang Sun Center for lignocellulosic Chemistry and Biomaterials College of Light Industry and Chemical EngineeringDalian Polytechnic UniversityDalianChina Department of Mechanical and Materials Engineering University of Western OntarioLondonOntarioCanada Institute of Physical Science and Information Technology Anhui UniversityHefeiChina

Applications of lithium-sulfur(li-S)batteries are still limited by the sluggish conversion kinetics from polysulfide to li_(2)*** various single-atom catalysts are available for improving the conversion kinetics,the sulfur redox kinetics for li-S batteries is still not ***,in this work,a catalyst with dual-single-atom Pt-Co embedded in N-doped carbon nanotubes(Pt&Co@NCNT)was proposed by the atomic layer deposition method to suppress the shuttle effect and synergistically improve the interconversion kinetics from polysulfides to li_(2)*** X-ray absorption near edge curves indicated the reversible conversion of li_(2)Sx on the S/Pt&Co@NCNT ***,density functional theory demonstrated that the Pt&Co@NCNT promoted the free energy of the phase transition of sulfur species and reduced the oxidative decomposition energy of li_(2)*** a result,the batteries assembled with S/Pt&Co@NCNT electrodes exhibited a high capacity retention of 80%at 100 cycles at a current density of 1.3 mA cm^(−2)(S loading:2.5 mg cm^(−2)).More importantly,an excellent rate performance was achieved with a high capacity of 822.1 mAh g^(−1) at a high current density of 12.7 mA cm^(−2).This work opens a new direction to boost the sulfur redox kinetics for ultrafast li-S batteries.

关键词： DFT calculation dual-single-atoms of Pt-Co fast li-sulfur batteries sulfur redox kinetics XANES analysis

Boosting reversible charging of li-ion batteries at low temperatures by a synergy of propylene carbonate-based electrolyte and defective graphite

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Nano Research 2024年第3期17卷 1491-1499页

作者： Yingqiang Wu Jiao Zhang Jinli liu li Sheng Bo Zhang limin Wang Siqi Shi li Wang Hong Xu Xiangming He Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing 100084China State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of Sciences(CAS)Changchun 130022China China National Quality Supervision and Inspection Center for Industrial Explosive Materials Nanjing University of Science and TechnologyNanjing 210094China School of Materials Science and Engineering Materials Genome InstituteShanghai UniversityShanghai 200444China

Propylene carbonate(PC)-based electrolytes have exhibited significant advantages in boosting the low-temperature discharging of graphite-based li-ion ***,it is still unclear whether they can improve the charging property and suppress lithium *** this topic is challenging due to the problem of electrochemical *** overcome this issue,we introduced graphite with phase *** results show that the pouch-type full batteries using PC-based electrolyte exhibit steady performance over 500 cycles and can be reversibly charged over 30 times at-20℃ with an average Coulombic efficiency of 99.95%,while the corresponding value for the conventional ethylene carbonate(EC)-based electrolyte sample is only 31.20%.This indicates that the use of PC-based electrolyte significantly suppresses lithium plating during low-temperature *** further demonstrate that the improved performance is mainly attributed to the unique solvation structure,where PF-6more anions participate in solvation,leading to the formation of a stable F-rich solid state electrolyte interface on the graphite surface and a lower reduction tendency of li+*** work inspires new ideas for the design of PC-based electrolytes for low-temperature charging and fast-charging batteries.

关键词： lithium-ion batteries graphite propylene carbonate low-temperature charging

Review Article li-current collector interface in lithium metal batteries

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Nano Research 2024年第10期17卷 8706-8728页

作者： Tian-Yu Wang Dingyi Zhao Keyue liang Yuzhang li Department of Chemical and Biomolecular Engineering University of CaliforniaLos AngelesLos AngelesCalifornia 90095USA

Interfaces within batteries,such as the widely studied solid electrolyte interface(SEI),profoundly influence battery *** these interfaces,the solid-solid interface between electrode materials and current collectors is crucial to battery performance but has received less discussion and *** review highlights the latest research advancements on the solid-solid interface between lithium metal(the next-generation anode)and current collectors(typically copper),focusing on factors affecting the li-current collector interface and improvement strategies from perspectives of current collector substrate(lithiophilicity,crystal facets,mechanical properties,and topological structure),electrolyte chemistry,current density,stacking pressure,SEI,electric field and temperature,and provides a future directions and opportunities on this topic.

关键词： lithium metal anode current collectors li-current collector interface solid-solid interface improvement strategies

组织工程软骨在生长板损伤修复治疗中的作用及特点

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中国组织工程研究 2021年第28期25卷 4539-4545页

作者：王香港万谦刘贺李容杭张妍李祖浩王金成吉林大学第二医院骨科吉林省长春市130041

背景:生长板调控着长骨纵向生长,如果发生损伤并导致骨桥形成会使长骨生长停滞,造成患肢成角畸形,而目前临床治疗方法效果不理想,用软骨组织工程制备的支架为临床治疗带来了希望。目的:介绍生长板的生理结构与功能,讨论并总结软骨组织... 详细信息

背景:生长板调控着长骨纵向生长,如果发生损伤并导致骨桥形成会使长骨生长停滞,造成患肢成角畸形,而目前临床治疗方法效果不理想,用软骨组织工程制备的支架为临床治疗带来了希望。目的:介绍生长板的生理结构与功能,讨论并总结软骨组织工程技术在生长板损伤治疗中所取得的进展。方法:作者以“Growth plate,Physis,Physeal,Scaffold,Cartilage tissue engineering,生长板,骺版,支架”为关键词,检索2000至2020年期间PubMed、Web of Science、CNKI和万方数据库中的相关文献,初检文献292篇,筛选后对65篇文献进行分析。结果与结论:在生长板损伤动物模型中,软骨组织工程支架表现出很好的治疗效果。具有生物活性的支架既填补了缺损、抑制骨桥形成、减轻了患肢的成角畸形,又诱导间充质干细胞分化为与生长板生理结构类似,呈柱状规则排列的软骨细胞。对众多实验结果进行总结发现,应用间充质干细胞联合适当的软骨诱导因子(如转化生长因子β、胰岛素样生长因子1等)可以促进软骨细胞大量生成并且排列有序,再生的软骨组织可以发挥生长板的正常功能,刺激长骨继续生长。另外,作为细胞黏附和生长因子缓释的载体,软骨组织工程支架应具有一定机械强度和良好的生物相容性,以往实验所用的单一天然生物材料或者合成高分子材料存在一定的缺点,尝试将两者结合制备成复合材料支架效果更好,但应用于临床治疗还需要更多的实验研究与探索。

关键词：软骨材料生长板软骨组织工程支架间充质干细胞软骨细胞细胞外基质综述

Process intensification for the synthesis and purification of battery-grade li_(2)CO_(3)with microfluidics

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Particuology 2024年第7期90卷 106-117页

作者： Haodu li Jie Zhang lin Dai Le Du Jiqin Zhu The State Key Laboratory of Chemical Resource Engineering College of Chemical EngineeringBeijing University of Chemical TechnologyBeijing 100029China

Battery-grade lithium carbonate(li_(2)CO_(3))with a purity of higher than 99.5 wt%is of great importance as a high value-added lithium ***,influences of different reaction systems and process control on product purity remain ***,a membrane dispersion microreactor was used to enhance the mass transfer of preparation and purification processes in homogeneous and heterogeneous *** systems of Na_(2)CO_(3)–liCl,NH_(4)HCO_(3)–liCl,and NH_(3)·H_(2)O−CO_(2)−liCl,CO_(2)purification based on carbonation and decomposition were *** li_(2)CO_(3)purity was increased by the improvement of mixing *** carbonation time was reduced by 62.5%and 58.3%for the NH_(3)·H_(2)O−CO_(2)and CO_(2)purification systems,*** the two ammonia-based systems,li_(2)CO_(3)particles with a purity of 99.7–99.8 wt%were one-step prepared with a size of 3–5μm,which also met the requirement of the battery-grade *** purity was further increased to 99.9 wt%by CO_(2)purification and liHCO_(3)*** investigation could provide a feasible alternative for the controllable preparation of battery-grade li_(2)CO_(3)in one or multiple steps.

关键词： Microfluidics Battery grade li_(2)CO_(3) Process intensification High purity

Polyimide covalent organic frameworks as efficient solid-state li^(+) electrolytes

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Science China Chemistry 2024年第5期67卷 1647-1652页

作者： Xu liu Shi Wang Siqi liu Chengfang liu Xiangchun li Jian Wu Dazhi li Shihao Xu Chongyang liu Wen-Yong Lai State Key Laboratory of Organic Electronics and Information Displays(SKLOEID) Institute of Advanced Materials(IAM)School of Chemistry and Life SciencesNanjing University of Posts&TelecommunicationsNanjing 210023China

Covalent organic frameworks(COFs) are attractive porous crystalline materials with extremely high stability, easy functionalization, and open channels, which are expected to be unique ion conductors/transporters in lithium ion batteries(liBs). Despite recent advances, low ion conductivity and low transference number, resulting in low charging/discharging rate, low energy density, and short battery life, are the main issues that limit their direct application as solid electrolytes in liBs. Here, we designed and synthesized a novel polyimide COF, namely, TAPA-PDI-COF, with abundant C=O groups, which has been successfully employed as high-performance solid electrolytes by doping TAPA-PDI-COF and succinonitrile(SN). Both the well-defined nanochannels of COFs and SN confined in the well-aligned channels restricted the free migration of anions, while C=O on COFs and CN groups of SN enhanced li^(+) transport, thus achieving a high ion conductivity of 0.102 m S cm^(-1)at 80 °C and a high lithium-ion transference number of 0.855 at room temperature. According to density functional theory(DFT)calculations, li-ion migration mainly adopted in-plane transport rather than the axial pathway, which may be due to the shorter hopping distances in the planar pathway. The results suggest an effective strategy for the design and development of all-solidstate ionic conductors for achieving high-performance liBs.

关键词： lithium ion batteries(liBs) covalent organic frameworks(COFs) solid-state ion conductors solid-state electrolytes ion conductivity

Semi-automated detection of rangeland runoff and erosion control berms using high-resolution topography data

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International Soil and Water Conservation Research 2024年第1期12卷 217-226页

作者： li li Changjiang River Scientific Research Institute of Changjiang Water Resources Commission Wuhan430010China Research Center on Mountain Torrent&Geologic Disaster Prevention Ministry of Water ResourcesWuhan430010China University of Arizona School of Natural Resources and the EnvironmentTucsonAZ85719USA

An inventory of topographic modifications is essential to addressing their impacts on hydrological and morphological processes in human-altered ***,such inventories are generally *** study presents two workflows for semi-automatic detection of linear earthen runoff and erosion control berms in rangelands using high-resolution topographic *** workflows consist of initial object identification by applying either morphological grayscale reconstruction(MGR)or the Geomorphon(GEO)method,followed by identification refinements through filters based on objects’horizontal and vertical *** sites were selected within the Altar Valley,Arizona,in the southwestern United *** site was used for developing workflows and optimizing filter thresholds,and the other two sites were used to validate *** results showed that:1)The MGR-based workflow methodology could produce final precision and detection rates of up to 92%and 75%,respectively,and take less than 5 s for a 10.1 km^(2) site;2)The workflow based on the MGR method yielded greater identification accuracy than did the GEO workflow;3)Object length,orientation,and eccentricity were important characteristics for identifying earthen berms,and are sensitive to general channel flow direction and berm shape;4)Manual interrogation of topographic data and imagery can significantly improve identification precision *** proposed workflows will be useful for developing inventories of runoff and erosion control structures in support of sustainable rangeland management.

关键词： Earthen berm Rangeland Grayscale morphological reconstruction Geomorphon liDAR

Effects of mid-passage gap with a variable surface angle on a turbine vane endwall’s aerothermal and film cooling performances

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Chinese Journal of Aeronautics 2024年第6期37卷 20-37页

作者： Zhiyu li Kaiyuan ZHANG Zhigang li Jun li Institute of Turbomachinery Xi’an Jiaotong UniversityXi’an 710049China

The mid-passage gap is an inevitable structure in a vane passage due to turbine vanes being manufactured *** coolant from this gap is able to prevent hot mainstream ingression and provide cooling protection for the endwall.A novel idea of enlarging the endwall’s coverage area and reducing the endwall’s thermal load by applying the mid-passage gap with variable surface angles is carried out in this *** endwall’s aerothermal and film cooling performances under four mid-passage gap modes at three typical mass flow ratio conditions are numerically *** indicate that under the traditional mid-passage mode,the coolant flows into the mainstream with a perpendicular incidence angle and can’t stick to the ***,cooling failure occurs,and the endwall’s thermal load is badly *** film cooling level at the suction-side endwall is improved when applying the mid-passage gap of a 45surface angle due to the secondary vortex being *** addition,when applying the mid-passage gap of a 135surface angle,the horseshoe vortex is pushed away,and the coverage area at the pressure-side endwall is enlarged *** best film cooling performance is achieved when the upstream surface angle is 135and the downstream surface angle is 45due to the adiabatic film cooling effectiveness being increased at both the pressure-and suction-side *** the mass flow ratio is 1.5%,the coverage area is enlarged by 43%,and the area-averaged adiabatic film cooling effectiveness is increased by 37%,when compared with those under the traditional mid-passage mode.

关键词： Film cooling Heat transfer Surface angle Mid-passagegap Turbinevane endwall