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陶瓷晶界特性(偏析、扩散和势垒)调控研究现状

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中国陶瓷 2024年第10期60卷 1-8页

作者：李思思任寅王亚红何琳陈刚高荣礼蔡苇王振华雷祥邓小玲符春林重庆科技大学化学化工学院重庆401331 重庆科技大学冶金与材料工程学院重庆401331 纳微复合材料与器件重庆市重点实验室重庆401331

晶界是陶瓷的重要组成部分,调控晶界是提升陶瓷性能(热电性能、介电性能、光学性能等)的重要手段。综述了陶瓷晶界的相关特性(重点是晶界偏析、晶界扩散和晶界势垒)以及近年来国内外学者对其调控取得的重要进展,并对陶瓷晶界调控亟待解... 详细信息

晶界是陶瓷的重要组成部分,调控晶界是提升陶瓷性能(热电性能、介电性能、光学性能等)的重要手段。综述了陶瓷晶界的相关特性(重点是晶界偏析、晶界扩散和晶界势垒)以及近年来国内外学者对其调控取得的重要进展,并对陶瓷晶界调控亟待解决的问题和未来的发展方向进行了展望。

关键词：陶瓷晶界偏析晶界扩散晶界势垒调控

Geomechanics model test and numerical simulation of 2G-NPR bolt support effect in an active fault tunnel

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Journal of Mountain Science 2022年第9期19卷 2729-2741页

作者： ren Shu-lin HE Man-chao LIN wei-jun ZHANG Teng-wu TAO Zhi-gang State Key Laboratory for Geomechanics&Deep Underground Engineering Beijing 100083China school of Mechanics and Civil Engineering China University of Mining&Technology Beijing 100083China 3 Department of Civil and Environmental EngineeringUniversity of AlbertaEdmonton T6G 1H9Canada

Active faults are a common adverse geological phenomenon that can occur during tunnel excavation and has a very negative impact on the construction and operation of the *** this paper,the grade IV rock surrounding the cross-fault tunnel with poor geological conditions has been chosen for the *** support capacity of 2^(nd) Generation-Negative Poisson’s Ratio(2G-NPR)bolt in an active fault tunnel has been carried out on the basis of relevant results obtained from the geomechanical model test and numerical investigations of failure model for existing unsupported fault *** investigation shows that surrounding rock of the tunnel is prone to shear deformation and crack formation along the fault,as a result,the rock mass on the upper part of the fault slips as a ***,small-scale deformation and loss of blocks are observed around the tunnel;however,the 2G-NPR bolt support is found to be helpful in keeping the overall tunnel intact without any damage and *** to the blocking effect of fault,the stress of the surrounding rock on the upper and lower parts of the fault is significantly different,and the stress at the left shoulder of the tunnel is greater than that at the right *** asymmetrical arrangement of 2G-NPR bolts can effectively control the asymmetric deformation and instability of the surrounding *** present numerical scheme is in good agreement with the model test results,and can reasonably reflect the stress and displacement characteristics of the surrounding rock of the *** comparison to unsupported and ordinary PR(Poisson’s Ratio)bolt support,2G-NPR bolt can effectively limit the fault slip and control the stability of the surrounding rock of the fault *** research findings may serve as a guideline for the use of 2G-NPR bolts in fault tunnel support engineering.

关键词： Tunnel engineering Fault 2G-NPR bolt Geomechanics model test Numerical simulation

A high time resolution and low-power ASIC for MRPC applications

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Radiation Detection Technology and Methods 2020年第1期4卷 63-69页

作者： Jia-yi ren wei wei Ru-yi Jin Jie Zhang gang Liu Xiao-shan Jiang Zheng wang State Key Laboratory of Particle Detection and Electronics Institute of High Energy PhysicsChinese Academy of Sciences(CAS)Beijing 100049China University of Chinese Academy of Sciences(UCAS) Beijing 100049China

Purpose The structure of readout circuits needs to be improved to meet the requirements of the endcap time of flight upgrade with multi-gap resistive plate chamber(MRPC)in Beijing SpectrometerⅢexperiments,posing a demand for the high time resolution and low-power *** Considering MRPC features,an application-specific integrated circuit(ASIC)called FEEWAVE,which integrates the front-end circuit and digitization function,is proposed to meet the above *** front-end circuit implements I/V conversion and signal *** reduce power consumption and further improve the time resolution,the waveform sampling technique based on switch capacitor array is *** and conclusion A 30 fC to 1.2 pC input signal dynamic range is obtained,and the jitter is less than 21 ps *** the same time,the chip realizes 5 GSPS(gigabit samples per second)sampling rate,trigger rate capability of 50 kHz and 25 mW/channel power *** 6-channel ASIC has been designed and taped out with 0.18μm complementary metal oxide semiconductor *** preliminary test results of FEEWAVE have been achieved.

关键词： MRPC Waveform sampling ASIC

带转向延误的非对称多模式用户平衡模型及算法

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中国公路学报 2006年第2期19卷 80-85页

作者：任刚王炜东南大学江苏省交通规划与管理重点实验室江苏南京210096

为了在网络建模中更精确地反映交通网络和出行行为的复杂特征,从多模式用户平衡原理出发,综合考虑多模式和转向延误因素以及不同模式、路段和转向之间的非对称作用,利用变分不等式理论建立了带转向延误的非对称多模式用户平衡模型,并在... 详细信息

为了在网络建模中更精确地反映交通网络和出行行为的复杂特征,从多模式用户平衡原理出发,综合考虑多模式和转向延误因素以及不同模式、路段和转向之间的非对称作用,利用变分不等式理论建立了带转向延误的非对称多模式用户平衡模型,并在精简对角化算法的框架内设计了求解算法。该模型集成了交通网络的诸多特征,且能直接刻画转向延误与转向流量之间的互动关系,避免了传统扩展网络法的缺陷。算例表明:该模型及其算法对问题的描述与求解是有效的。

关键词：交通工程用户平衡模型变分不等式理论精简对角化算法转向延误

基于ERK/NF-κB/COX-2信号通路研究珠子参总皂苷改善对乙酰氨基酚致小鼠肝损伤的作用机制

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中国中药杂志 2024年第10期49卷 2585-2596页

作者：石孟琼张继红周刚郭巍刘英包中文陈茂华谈发明胡慧泉汪鋆植任剑峡唐海明三峡大学基础医学院&肿瘤微环境与免疫治疗湖北省重点实验室湖北宜昌443002 三峡大学中医医院&湖北省功能性消化系统疾病中医临床医学研究中心湖北宜昌443002 湖北鄂州二医院药剂科湖北鄂州436000 宜昌市第二人民医院湖北宜昌443002 湖北恒安芙林药业股份有限公司湖北宜昌443199

研究珠子参总皂苷(total saponins of Panax japonicus,TSPJ)对对乙酰氨基酚(acetaminophen,APAP)诱导小鼠肝损伤的影响及作用机制。将雄性昆明小鼠随机分为空白组、TSPJ组(200 mg·kg^(-1),ig)、模型组、APAP+TSPJ低剂量组(50 mg·kg^(-1),ig)、APAP+TSPJ中剂量组(100 mg·kg^(-1),ig)、APAP+TSPJ高剂量组(200 mg·kg^(-1),ig)和APAP+N-乙酰半胱氨酸组(200 mg·kg^(-1),ip)。给药组每天ig或ip相应的药物,每天1次,连续14 d。末次给药1 h后,除空白组和TSPJ组外,各组小鼠均灌胃给予500 mg·kg^(-1) APAP,24 h后收集小鼠血清与肝脏组织进行血清中丙氨酸氨基转移酶(alanine aminotransferase,ALT)、天冬氨酸氨基转移酶(aspartate aminotransferase,AST)、活性氧(reactive oxygen species,ROS)、肿瘤坏死因子(tumor necrosis factor,TNF)-α、白细胞介素(interleukin,IL)-1β、环氧合酶(cyclooxygenase,COX)-2、IL-6、IL-4、IL-10及肝组织中乳酸脱氢酶(lactate dehydrogenase,LDH)、谷胱甘肽(glutathione,GSH)、超氧化物歧化酶(superoxide dismutase,SOD)、过氧化氢酶(catalase,CAT)、总抗氧化能力(total antioxidant capacity,T-AOC)、丙二醛(malondialdehyde,MDA)、髓过氧化物酶(myeloperoxidase,MPO)的水平,苏木精-伊红染色观察肝组织形态学改变;实时定量PCR法测定肝组织中淋巴细胞抗原6G(lymphocyte antigen 6G,Ly6G)、半乳糖凝集素3(galectin 3,Mac-2)、TNF-α、IL-1β、COX-2、IL-6、IL-4、IL-10 mRNA表达,Western blot法测定肝组织中Ly6G、Mac-2、细胞外调节蛋白激酶(extracellular regulated protein kinase,ERK)、磷酸化细胞外信号调节激酶(phosphorylated extracellular regulated protein kinase,p-ERK)、COX-2、核因子κB抑制因子α(inhibitor of nuclear factorκB protein α,IκBα)、磷酸化核因子κB抑制因子α(phosphorylated inhibitor of nuclear factorκB protein α,p-IκBα)、胞浆和胞核中核因子κB亚基p65(nuclear factorκB subunit p65,NF-κB p65)蛋白表达。结果显示,TSPJ可显著降低APAP诱导小鼠肝脏系数、血清中ALT、AST、ROS、TNF-α、IL-1β、IL-6、COX-2水平及肝组织LDH、MPO、MDA水平和肝组织中TNF-α、IL-1β、IL-6 mRNA表达,升高血清中IL-4、IL-10含量及肝组织中GSH、CAT、SOD、T-AOC水平和肝组织中IL-4、IL-10 mRNA表达;改善肝脏病理损伤程度,抑制肝组织中性粒细胞浸润和巨噬细胞募集;降低肝组织中中性粒细胞标记物Ly6G、巨噬细胞标记物Mac-2和COX-2 mRNA和蛋白表达,降低p-ERK、p-IκBα、胞核NF-κB p65蛋白表达和p-ERK/ERK、p-IκBα/IκBα比率,升高胞浆NF-κB p65蛋白表达。以上结果表明,TSPJ对APAP诱导的小鼠肝损伤有显著保护作用、可减轻APAP引起的氧化损伤与炎症反应,其作用机制与抑制ERK/NF-κB/COX-2信号通路激活,进而抑制炎性细胞浸润、炎症因子生成和抑制肝细胞损伤密切相关。

关键词：珠子参总皂苷对乙酰氨基酚氧化损伤炎症反应细胞外调节蛋白激酶/核因子κB/环氧合酶-2信号通路

Interface stabilization of 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether to high-voltage Li-rich Mn-based layered cathode materials

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Rare Metals 2022年第3期41卷 822-829页

作者： A-Lin Li Guo-Hua Li Shi-gang Lu Zhi-Min ren Jian-Tao wang Hao-Xiang Zhuo wei Quan gang-Ning Zhang Fu-Juan Han Yi-Mian Xia Jing wang Yi Zhang National Power Battery Innovation Center Grinm Group Company LtdBeijing 100088China China Automotive Battery Research Institute Company Ltd Beijing 101407China General Research Institute for Nonferrous Metals Beijing 100088China Materials Genome Institute Shanghai UniversityShanghai 200444China

Non-aqueous electrolyte solvents play a pivotal role in improving the cycling performance of high-voltage Li-rich Mn-based layered cathode materials. In this study, a fluoroether (1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether, TFEPE) was added to 1.2 mol·L^(-1)LiPF_(6)EC/EMC/DEC at different concentrations to synthesize a series of electrolytes for enhancing the cycling performance of highvoltage Li_(1.18)Mn_(0.50)Ni_(0.26)Co_(0.06)O_(2)(LMNC).

关键词： materials. cycling 1,2

Research on goal-setting method of rock drivage based on the balance among period, cost and quality

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Journal of Coal Science & Engineering(China) 2012年第2期18卷 218-224页

作者： SHAN ren-liang CAI wei-ling wang Yu-bao LI Dong-gang CHEN Xiang school of Mechanics&Civil Engineering China University of Mining and Technology(Beijing)Beijing 100083China Xishan Coal&Electricity Group Corporation Taiyuan 030053China Shanxi Coking Coal Group Taiyuan 030024China school of Management Hebei University of EngineeringHandan 056038China

On the basis of the analysis on the disadvantages of the original goal-setting about rock drivage, this paper defined the ＂life cycle quality＂. With project management theory and the Cobb-Douglas function, ＂quality-cost and quality-price curve model＂ and the ＂total cost-period prediction model＂ were built. Then the goal-setting method of the balance among quality, cost and period of rock drivage was constructed by finding ＂life cycle cost＂ through ＂life cycle quality＂ using ＂quality-cost and quality-price curve model＂ and ensuring period through ＂life cycle cost＂ using ＂total cost-period prediction model＂（hereinafter referred to as the ＂three goals balance method＂）. ＂Value contribution＂ which is the value of the contribution to a mine because of rock drivage, was found in the process of constructing the ＂quality-cost and quality-price curve model＂. An industrial test was done in coal mine A with the research results, staff footage efficiency improved by 24.24%, the period shortened by 14.3%, the ＂life cycle cost＂ dropped by 2.09%, the ＂life cycle quality price＂ improved by 3.29%, and value contribution increased by 25.3%. The result shows that the new goal method setting on the basis of coal mine profit maximization can ensure construc- tion period. At the same time, it can realize cost and quality objectives and the optimization and balance of relationship among them; rewarding excavation teams by ＂value contribution＂ can combine organizational goal with personal goal, it significantly raise the employee＇s work efficiency.

关键词： goal-setting life cycle theory balance among quality and cost and period value contribution

淬火温度对S590粉末冶金高速钢组织和性能的影响

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粉末冶金技术 2024年第1期42卷 75-83页

作者：祁进坤岳永文胡剑赵钢寇晓磊齐国强王宏升任淑彬河北五维航电科技股份有限公司张家口075699 北京科技大学新材料技术研究院北京100083

采用等离子旋转电极雾化和热等静压法制备S590粉末冶金高速钢,分别在1050、1100、1150和1180℃进行淬火热处理,并经过一次550℃回火(1 h),一次−196℃深冷处理(4 h)和两次550℃回火(1 h),研究不同淬火温度对S590粉末冶金高速钢微观组织... 详细信息

采用等离子旋转电极雾化和热等静压法制备S590粉末冶金高速钢,分别在1050、1100、1150和1180℃进行淬火热处理,并经过一次550℃回火(1 h),一次−196℃深冷处理(4 h)和两次550℃回火(1 h),研究不同淬火温度对S590粉末冶金高速钢微观组织和力学性能的影响。结果表明:热处理后S590高速钢微观组织主要包括马氏体、M6C型碳化物和MC型碳化物。随淬火温度升高,碳化物逐渐溶入基体中,数量减少,基体晶粒尺寸变大。高速钢硬度和抗压强度随淬火温度升高呈上升趋势,1180℃淬火试样经后续热处理后,硬度可达HRC 67.8,抗压强度为3827 MPa;抗弯强度随淬火温度的升高先上升后下降,冲击韧性随淬火温度升高而下降,1100℃淬火试样抗弯强度达到最高,为5473 MPa;1050℃淬火试样冲击韧性最高,为76.9 J·cm^(−2)。综合考虑显微组织和力学性能,S590粉末冶金高速钢的最优淬火温度为1100℃。

关键词：淬火温度粉末冶金高速钢热处理力学性能

Tensile Properties of TWIP Steel at High Strain Rate

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Journal of Iron and Steel Research International 2009年第1期16卷 81-86,21页

作者： XIONG Rong-gang FU ren-yu SU Yu LI Qian wei Xi-cheng LI Lin school of Materials Science and Engineering Shanghai University Shanghai 200072 China

Tensile tests of TWIP steels of two compositions are performed in the strain rate range of 10^-5-10^3 s^-1. Results indicate that steel 1^# does not exhibit TWIP effect but deformation-induced martensitic transformation appears only. There exists TWIP effect in steel 3^# . Tensile properties at room temperature are sensitive to strain rate in the studied strain rate ranges. Analysis on the relationship between strain-hardening exponent and strain rates shows that strain induced martensitic transformation and formation of twins during deformation have significant in- fluence on their strain-hardening behavior.

关键词： twin-induced plasticity strain rate strain hardening deformation twin