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The noise matrix theory of two-port network--The noise analysis of a feedback amplifier

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Chinese Science Bulletin 1997年第19期42卷 1665-1669页

作者： Dai, YS Qian, zh Li, YQ Department of Electronics Engineering Jilin University of Technology Changchun 130025 China

THE low-noise preamplifier, as one of the major circuits in signal detection system, consists ofthe low noise amplifier and the feedback network. The low noise amplifier design aims both tocalculate the optimal source impedance and minimum noise figure, and to compare the noiseperformance and other characteristics of variant circuits and components. The conventional ap-proach to noise analysis of an electronic circuit is to calculate the output noise power of the

关键词： two-port network noise spectral density matrix feedback amplifier.

STUDIES　oN　THE　NoN－ISoTHERMAL　KINETICS　oF　THERMAL　DECoMPoSITIoNS　oF　THE　CoMPLEXES　oF　Cd（II）WITH　o－VANILLIN　THIoSEMICARBAZoNE　AND　IRoN（III）WITH　2－［（o－HYDRoXYBENZYLIDENE）AMINo］PHENoL　AND　PYRIDINE

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Chinese Chemical Letters 1995年第7期6卷 637-640页

作者： Hu, QP Cui, XG Yang, zh Shandong Univ Dept Chem Jinan 250100 Peoples R China Shandong Univ Inst Crystal Mat Jinan 250100 Peoples R China

The thermal decompositions of the complex of Cd(II) with o-vanillin thiosemicarbazone (complex 1) and the mixed ligand complex of iron (III) with 2-[(o-hydroxybenzylidene)amino] phenol and pyridine (complex 2) and their non-isothermal kinetics have been studied by TG and DTG *** non-isothermal kinetic data were analyzed and the kinetic parameters for the first and second steps of the thermal decompositions were evaluated by twodifferent methods -- differential and integral methods. Their kinetic equatiolls were obtained.

关键词： III IRoN THIoSEMICARBAZoNE AMINo AND

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中国有色金属学会会刊：英文版 2001年第6期11卷 843-846页

作者： Yan, HG Chen, zh Kang, ZT Chen, G Hunag, PY Hunan Univ Sch Mat Sci & Engn Changsha 410082 Peoples R China Cent S Univ Dept Mat Sci & Engn Changsha 410083 Peoples R China

The phase formation regularities in nanometer powders of ternary alloys prepared by gas evaporation process with induction current as the heating source were investigated. Al-Cu-Mn and Al-Cu-Cr were chosen as the samples in this study. The experimental results show that the necessary conditions for forming ternary compound phases in a ternary alloy nanometer powder are that they must be able to form in a conventional bulk alloy. To obtain a ternary compound phase in nanometer powders, composition of the master alloy must be in a certain range. Changing the composition of the master alloy and evaporation temperature can control the kinds of the phases and their relative amount in the alloy nanometer powders. In present study, AlMn, Al8Mn5 and AlCu2Mn phases formed in as-prepared nanometer powders of Al-Cu-Mn alloy, and the highest relative amount of AlCu2Mn phase is about 99%. In nanometer powders of Al-Cu-Cr alloy,Cu9Al4, Al2Cu3, AlCr2 and Al13Cr2 phases formed without any ternary compound phase.

关键词： nanometer powder gas evaporation alloy powder

ELECTRoN　TRANSFER　AGENT　DEPENDENCY　oF　MoNooXYGENATIoN　oF　CYCLoHEXANE　CATALYZED　BY　SILICA　IMMoBILIZED　N，N＇－BIS［2－（BENZIMIDAZoLYLMETHYL）］AMINo　FERRoUS　ACETATE　CoMPLEX

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Chinese Chemical Letters 1996年第1期7卷 47-50页

作者： Wang, TJ Ma, zh Huang, MY Jiang, YY ACAD SINICA INST CHEM BEIJING 100080 PEOPLES R CHINA

Silica the N, N'-bis[-2-(benzimidazolylmethyl)]amino-ferrous acetate complexes (Ⅳ)catalyzed monooxygenation of cyclohexane to cyclohexanol with the turnover muber(equrvalent C%= 11. 2)under mild *** methylene bule is the most effective electron transfer agent which can also regulate products distribution. The iron content of the polymer-supported complexes, the redox potentials and the concentration of methylene blue greatly affect the activity and selectivity of the complex (Ⅳ).

关键词： oXIDATIoN

Fast magnetic energy dissipation in relativistic plasma induced by high order laser modes

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High Power Laser Science and Engineering 2016年第2期4卷 85-89页

作者： Y.J.Gu Q.Yu o.Klimo T.zh.Esirkepov S.V.Bulanov S.Weber G.Korn Institute of Physics of the ASCR Institute of Modern Physics Fudan University FNSPE Czech Technical University in Prague Kansai Photon Science Institute Japan Atomic Energy Agency

Fast magnetic field annihilation in a collisionless plasma is induced by using TEM(1,0) laser pulse. The magnetic quadrupole structure formation, expansion and annihilation stages are demonstrated with 2.5-dimensional particle-in-cell simulations. The magnetic field energy is converted to the electric field and accelerate the particles inside the annihilation plane. A bunch of high energy electrons moving backwards is detected in the current sheet. The strong displacement current is the dominant contribution which induces the longitudinal inductive electric field.

关键词： high order laser mode laser–plasma interaction magnetic annihilation

DYNAMIC ANALYSIS oF ARREST oF BUCKLE PRoPAGATIoN oN A BEAM oN A NoNLINEAR ELASTIC FoUNDATIoN BY FEM

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Acta Mechanica Solida Sinica 1997年第1期10卷 28-30,32-35页

作者： Zou, SZ Huang, YY Liu, zh Qian, Q SHASHI UNIV SHASHI 434000PEOPLES R CHINA HUAzhoNG UNIV SCI & TECHNoL WUHAN 430074PEOPLES R CHINA ACAD SINICA INST MECHBEIJING 100080PEOPLES R CHINA

Based on the dynamic governing equation of propagating buckle on a beam on a nonlinear elastic foundation, this paper deals with an important problem of buckle arrest by combining the FEM with a time integration technique. A new conclusion completely different from that by the quasi-static analysis about the buckle arrestor design is drawn. This shows that the inertia of the beam cannot be ignored in the analysis under consideration, especially when the buckle propagation is suddenly stopped by the arrestors.

关键词： buckle propagation arrest of buckle beam on a nonlinear foundation finite element method

Regime dynamics of hydrochemical and toxicological parameters of the Irtysh River in Kazakhstan

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Journal of Arid Land 2016年第4期8卷 521-532页

作者： Diana M BURLIBAYEVA Malik zh BURLIBAYEV Christian oPP BAo Anming Department of Water Resources and Land Reclamation Kazakh National Agrarian UniversityAlmaty 050010Kazakhstan Kazakhstan Agency of Applied Ecology Almaty 050012Kazakhstan Department Hydrology&Soil Science Faculty of GeographyPhilipps UniversityMarburg 35032Germany Xinjiang Institute of Ecology and Geography Chinese Academy of SciencesUrumqi 830011China

Since the Irtysh River flows through the important economic, ecological and social territories of China, Kazakhstan and Russia, the water quality issues growingly draw the attention of the water authorities from these countries. Therefore, a detailed study of the hydrochemical regime and toxicological indicators in Kazakhstan was carried out for understanding the regime dynamics of water quality and its affect factors. The combined assessment of maximum permissible concentration （MPC） of chemical components and biotesting method were proposed and performed for the study area. The results clearly showed that the concentrations of single chemical component at different locations are mostly under MPC standard in a basin scale. However, the watershed surface runoff and tributary stream flow from mining industry areas had high concentration of heavy metals and had significant impact on the water quality near Ust-Kamenogorsk. Furthermore, even the stream water generally meet MPC standard, the results of biotesting method show the toxicity level of water sample is lethal for the test objects of phytoplankton and Daphnia. The survival rates of most water samples are lower than 46.7%. Hereby, this study strongly suggests using combined water assessment methods to evaluate the water quality.

关键词： hydrochemistry biotesting method Irtysh River Kazakhstan

The W-11-4A Platform Comprehensive Strength Monitoring System

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China ocean Engineering 1998年第2期13卷 135-146页

作者： Shen, zh Li, H Xue, YI Chen, JC zh.o, Q Chinese Acad Sci Inst Mech Beijing 100080 Peoples R China Louisiana Tech Univ Appl & Computat Anal & Modeling Program Ruston LA 71272 USA Acad Sinica S China Sea Inst Oceanol Guangzhou 510301 Peoples R China

A comprehensive strength monitoring system used on a fixed jacket platform is presented in this paper. The long-term monitoring of W-11-4A platform achieved. Structural responses (strain and acceleration) at selected locations, as well as associated environmental parameters, have been obtained. The emphasis of the paper is placed on the system design, and the instrumentation and operation methodology employed in the monitoring of the structural responses. The performance of the system and the characteristic results obtained during its 13-month operation are also summarized.

关键词： monitoring techniques comprehensive strength monitoring structural responses waterproof strain transducers underwater instrumentation techniques

早期康复护理对吉兰-巴雷综合征患者肌力及日常生活活动能力的影响

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罕少疾病杂志 2024年第8期31卷 148-149,158页

作者：位亚娟王静张新勋郑州大学第一附属医院神经重症监护病房河南郑州450052

目的探究早期康复护理在吉兰-巴雷综合征(GBS)患者中的应用效果。方法选取2021年1月~2023年12月本院收治的GBS患者72例,根据护理方案进行分组,对照组40例患者进行常规护理,观察组32例患者进行早期康复护理。比较两组的四肢肌力、日常生... 详细信息

目的探究早期康复护理在吉兰-巴雷综合征(GBS)患者中的应用效果。方法选取2021年1月~2023年12月本院收治的GBS患者72例,根据护理方案进行分组,对照组40例患者进行常规护理,观察组32例患者进行早期康复护理。比较两组的四肢肌力、日常生活活动能力、自我效能感以及生活质量。结果干预前两组患者各项指标之间均无显著性差异(P>0.05);干预后,观察组上、下肢近端及远端肌力、改良Barthel指数(MBI)、一般自我效能感量表(GSES)、简明健康状况问卷(SF-36)评分较对照组均明显升高(P<0.05)。结论在GBS患者中,应用早期康复护理可明显改善其四肢肌力,显著提升患者的日常生活活动能力,有效提高患者的自我效能感及生活质量,值得临床推广。

关键词：早期康复护理 GBS 肌力日常生活活动能力