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KINETIC STUDY OF SPINEL LiMn_2O_4 SYNTHESIZED BY SOLID REACTION w.TH SOFT-CHEMICAL METHOD

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Acta Metallurgica Sinica(English Letters) 2005年第4期18卷 512-518页

作者： C.Q. xu Y. w. Tian Y. C. Zhai Z.J. Guo Z. Q. Huang School of Materials and Metallurgy Northeastern University Shenyang 110004 China

The differential thermal analysis （DTA） curves w.re measured at different heating rates in flow.ng air for studying the synthesis of the spinel LiMn2O3 w.th Li2CO3 and MnO2, The reaction began at about 503K, and finished at about 873K. The apparent activation energy of Kissinger method w.s about ***^-1, the reaction orderw.s 1.67, the frequency factor w.s 7.81×10^9, and therefore the dinetic epuation w.s dδ/dt=A·exp（- E/RT）·（1-δ）^n=7.81×10^9, exp（-122770/RT）·（l-δ）^1.67 . Coats-Redfem integral method w.s used to analyze the DTA curves of the samples at different heating rates, and the calculated apparent activation energy and frequency factor w.re 112. 13kJ· mol^-1 and 1.18 × 10^9, respectively, rather close to that of Kissinger method. X-ray diffraction （XRD） and scanning electron microscope （SEM） results show. that the synthesized LiMn2O3 possesses pure phase, regular shape and normal particle distribution.

关键词： lithium manganese oxides synthesized kinetics Kissinger method,Coats-Redfern integral method

The Characterization of Sputtered Zr-Ge-N Thin Films as Diffusion Barriers Betw.en Copper and Silicon

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稀有金属材料与工程 2012年第S1期41卷 120-123页

作者： Yang, J. J. Liu, B. Liao, X. D. Jiao, G. H. xu, K. w. Sichuan Univ Inst Nucl Sci & Technol Minist Educ Key Lab Radiat Phys & Technol Chengdu 610064 Peoples R China CAS Xian Inst Opt & Precis Mech State Key Lab Transient Opt & Photon Xian 710049 Peoples R China Xi An Jiao Tong Univ State Key Lab Mech Behav Mat Xian 710049 Peoples R China

The main purpose of the present micro-structural analysis by transmission electron microscopy(TEM)and X-ray diffraction(XRD)w.s to investigate w.ether amorphous Zr-Ge-N films are a potential candidate as a diffusion barrier for Cu w.ring used in Si *** Zr-Ge-N films w.re prepared by a radio frequency(RF)reactive magnetron sputter-deposition technique using N2 and Ar mixed gas,and the film structure w.s found to be sensitive to the gas flow.ratio of N2 *** during *** Zr-Ge-N films w.re obtained w.en the N2/(Ar+N2)ratio w.s smaller than 0.2 and amorphous-like Zr-Ge-N films w.re obtained w.en the ratio w.s larger than *** barrier test w.s performed by annealing the Cu/Zr-Ge-N/Si film stack under Ar *** deposited Zr-Ge-N(C)films remained amorphous even after high temperature *** Cu diffusion profile in the film w.s assessed by the Auger electron spectroscopy(AES).The results indicate that Cu diffusion w.s minimal in amorphous Zr-Ge-N(C)films even at high annealing temperatures of 800℃.

关键词： Zr-Ge-N films diffusion barrier micro-structural thermal stability

DIFFERENTIAL SCANNING CALORIMETRY AND X-RAY DIFFRACTION STUDIES ON AGING BEHAVIOR OF Zn-Al ALLOYS

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Acta Metallurgica Sinica(English Letters) 2001年第2期14卷 109-114页

作者： X.L. xu, Z. w. Yu, S.J. Ji, J.C. Sun and Z.K. Hei (Dalian Maritime University, Dalian 116024, China) Dalian Maritime University

Decomposition processes of the quenched Zn-Al alloys w.re studied by differential scanning calorimetry (DSC), X-ray diffraction (XRD) and transmission electron microscopy (TEM). The results show.that the stabilities of supersaturated solid solution (SSS) of Zn-Al alloy and α' phase formed by quenching w.uld reduce w.th the increase of Zn content and the precipitation of η-Zn phases even w.en aging at ambient temperature, so that the exothermic precipitation peak in DSC curve w.uld disappear. The activation energy of the η-Zn precipitation and the reaction enthalpy w.re calculated and measured. The kinetics of α' decomposition or η-Zn formation w.s determined by XRD. The microstructure change during aging w.s observed by TEM.

关键词： Aging of materials Aluminum alloys Differential scanning calorimetry X ray diffraction

基于Hilbert变换的全波场分离逆时偏移成像

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地球物理学报 2016年第11期59卷 4200-4211页

作者：王一博郑忆康薛清峰常旭 Tong w.Fei Yi Luo 中国科学院地质与地球物理研究所 EXPEC ARC Saudi AramcoDhahran 31311Saudi Arabia

逆时偏移方法利用双程波算子模拟波场的正向和反向传播,通常采用互相关成像条件获得偏移剖面,是一种高精度的成像方法.但是传统的互相关成像条件会在偏移结果中产生低频噪声;此外,如果偏移速度中存在剧烈速度变化还可能进一步产生偏移假... 详细信息

逆时偏移方法利用双程波算子模拟波场的正向和反向传播,通常采用互相关成像条件获得偏移剖面,是一种高精度的成像方法.但是传统的互相关成像条件会在偏移结果中产生低频噪声;此外,如果偏移速度中存在剧烈速度变化还可能进一步产生偏移假象.为了提高逆时偏移的成像质量,可在成像过程中先对震源波场和检波点波场分别进行波场分离,然后选择合适的波场成分进行互相关成像.本文基于Hilbert变换,推导了可在偏移过程中进行上下行和左右行波场分离的高效波场分离公式以及相应的成像条件,结合Sigsbee 2B合成数据,给出了不同波场成分的互相关成像结果.数值算例结果表明,采用本文提出的高效波场分离算法以及合理的波场成分互相关成像条件可以获得高信噪比的成像结果.

关键词：逆时偏移互相关成像条件波场分离 Hilbert变换

Effects of PI3-k/Akt short hairpin RNA on proliferation, fibronectin production and synthesis of thrombospondin-1 and transforming grow.h factor-beta（1 ） in glomerular mesangial cells induced by sublytic C5b-9 complexes

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南京医科大学学报（自然科学版） 2009年第3期29卷 344-344页

作者： Gao, L. Zhang, Y. Qiu, w. xu, w. Feng, X. Ren, J. Jiang, X. w.ng, H. Zhao, D. w.ng, Y. Nanjing Med Univ Dept Microbiol & Immunol Nanjing 210029 Peoples R China.

全尺寸径向滑动轴承试验台上轴承油膜参数识别

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润滑与密封 1998年第1期23卷 18-21页

作者：姜歌东谢友柏胡虹徐谓金志伟西安交通大学润滑理论及轴承研究所 710049 东方汽轮机厂德阳618000

首先,概述了以不改变全尺寸静特性实验台整体结构为前提,在原有实验台上添加激振装置和测试仪器,增加动特性测试功能的必要和可能性.其次,概述了脉冲激励、振动测量、数据采集记录及动特性识别的基本原理.最后,将测量结果与理论计算作... 详细信息

首先,概述了以不改变全尺寸静特性实验台整体结构为前提,在原有实验台上添加激振装置和测试仪器,增加动特性测试功能的必要和可能性.其次,概述了脉冲激励、振动测量、数据采集记录及动特性识别的基本原理.最后,将测量结果与理论计算作了比较,并讨论了可能产生误差的各种原因.

关键词：径向轴承实验台油膜系数参数识别滑动轴承

Aquaporin-4-IgG-seropositive neuromyelitis optica spectrum disorders:progress of experimental models based on disease pathogenesis

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Neural Regeneration Research 2025年第2期20卷 354-365页

作者： Li xu Huiming xu Changyong Tang Department of Neurology The Third Affiliated Hospital of Sun Yat-sen UniversityGuangzhouGuangdong ProvinceChina

Neuromyelitis optica spectrum disorders are neuroinflammatory demyelinating disorders that lead to permanent visual loss and motor *** date,no effective treatment exists as the exact causative mechanism remains ***,experimental models of neuromyelitis optica spectrum disorders are essential for exploring its pathogenesis and in screening for therapeutic *** most patients w.th neuromyelitis optica spectrum disorders are seropositive for IgG autoantibodies against aquaporin-4,w.ich is highly expressed on the membrane of astrocyte endfeet,most current experimental models are based on aquaporin-4-IgG that initially targets *** experimental models have successfully simulated many pathological features of neuromyelitis optica spectrum disorders,such as aquaporin-4 loss,astrocytopathy,granulocyte and macrophage infiltration,complement activation,demyelination,and neuronal loss;how.ver,they do not fully capture the pathological process of human neuromyelitis optica spectrum *** this review.w. summarize the currently know. pathogenic mechanisms and the development of associated experimental models in vitro,ex vivo,and in vivo for neuromyelitis optica spectrum disorders,suggest potential pathogenic mechanisms for further investigation,and provide guidance on experimental model *** addition,this review.summarizes the latest information on pathologies and therapies for neuromyelitis optica spectrum disorders based on experimental models of aquaporin-4-IgG-seropositive neuromyelitis optica spectrum disorders,offering further therapeutic targets and a theoretical basis for clinical trials.

关键词： aquaporin-4 experimental model neuromyelitis optica spectrum disorder pathogenesis

Reducing the measurement errors in nonadiabatic holonomic quantum computers

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 64-70页

作者： Guo-Fu xu Department of Physics Shandong University

Nonadiabatic holonomic quantum computers serve as the physical platform for nonadiabatic holonomic quantum *** quantum computation has entered the noisy intermediate-scale era, building accurate intermediate-scale nonadiabatic holonomic quantum computers is clearly necessary. Given that measurements are the sole means of extracting information, they play an indispensable role in nonadiabatic holonomic quantum computers. Accordingly, developing methods to reduce measurement errors in nonadiabatic holonomic quantum computers is of great importance. How.ver, w.ile much attention has been given to the research on nonadiabatic holonomic gates, the research on reducing measurement errors in nonadiabatic holonomic quantum computers is severely lacking. In this study, w. propose a measurement error reduction method tailored for intermediate-scale nonadiabatic holonomic quantum computers. The reason w. say this is because our method can not only reduce the measurement errors in the computer but also be useful in mitigating errors originating from nonadiabatic holonomic gates. Given these features,our method significantly advances the construction of accurate intermediate-scale nonadiabatic holonomic quantum computers.

关键词： quantum holonomy quantum computation measurement errors

Mitophagy in acute central nervous system injuries:regulatory mechanisms and therapeutic potentials

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Neural Regeneration Research 2025年第9期20卷 2437-2453页

作者： Siyi xu Junqiu Jia Rui Mao Xiang Cao Yun xu Department of Neurology Nanjing Drum Tower HospitalClinical College of Jiangsu UniversityNanjingJiangsu ProvinceChina Department of Neurology Nanjing Drum Tower HospitalChinese Academy of Medical Science&Peking Union Medical CollegeNanjingJiangsu ProvinceChina Department of Neurology Nanjing Drum Tower HospitalAffiliated Hospital of Medical SchoolNanjing UniversityNanjingJiangsu ProvinceChina State Key Laboratory of Pharmaceutical Biotechnology and Institute of Translational Medicine for Brain Critical Diseases Nanjing UniversityNanjingJiangsu ProvinceChina Jiangsu Key Laboratory for Molecular Medicine Medical School of Nanjing UniversityNanjingJiangsu ProvinceChina Nanjing Neurology Medical Center NanjingJiangsu ProvinceChina

Acute central nervous system injuries,including ischemic stro ke,intracerebral hemorrhage,subarachnoid hemorrhage,traumatic brain injury,and spinal co rd injury,are a major global health *** optimal therapies and improving the long-term neurological functions of patients w.th acute central nervous system injuries are urgent *** are susceptible to damage after acute central nervous system injury,and this leads to the release of toxic levels of reactive oxygen species,w.ich induce cell ***,a selective form of autophagy,is crucial in eliminating redundant or damaged mitochondria during these *** evidence has highlighted the significant role of mitophagy in acute central nervous system *** this review.w. provide a comprehensive overview.of the process,classification,and related mechanisms of *** also highlight the recent developments in research into the role of mitophagy in various acute central nervous system injuries and drug therapies that regulate *** the final section of this review.w. emphasize the potential for treating these disorders by focusing on mitophagy and suggest future research paths in this area.

关键词： autophagy intracerebral hemorrhage ischemic stroke mitochondria mitochondrial biogenesis mitochondrial quality control mitophagy spinal cord injury subarachnoid hemorrhage traumatic brain injury