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Biomedical and Environmental Sciences 2024年第1期37卷 42-53页

作者： JI Xiao Ning LIU Zhao Ping ZHANG Chao Zheng CHEN Min LIANG Jiang LU Jiang ZHANG Lei National resource Center for Chinese Materia Medica China Academy of Chinese Medical SciencesBeijing 100700China China National Center for Food Safety risk Assessment Beijing 100022China Chinese Center for disease Control and Prevention Beijing 102206China

Objective This study aimed to investigate the effect and underlying mechanism of Fructus lycii in improving exercise *** A network pharmacological approach was used to explore potential mechanisms of action of Fructus *** muscle C2C12 cells and immunofluorescence were employed to verify the effect and mechanism of the representative components in Fructus lycii predicted by network pharmacological *** Six potential active components,namely quercetin,β-sitosterol,stigmasterol,7-Omethylluteolin-6-C-beta-glucoside_qt,atropine,and glycitein,were identified to have potency in improving exercise fatigue via multiple pathways,such as the PI3K-Akt,neuroactive ligand-receptor interaction,IL-17,TNF,and MAPK signaling *** immunofluorescence results indicated that quercetin,a significant active component in Fructus lycii,increased the mean staining area of 2-NBdG,TMrM,and MitoTracker,and decreased the area of Cellrox compared to the ***,the protein expression levels of p-38 MAPK,p-MAPK,p-JNK,p-PI3K,and p-AKT markedly increased after quercetin *** Fructus lycii might alleviate exercise fatigue through multiple components and *** these,quercetin appears to improve exercise fatigue by enhancing energy metabolism and reducing oxidative *** PI3K-AKT and MAPK signaling pathways also appear to play a role in this process.

关键词： Fructus lycii Exercise fatigue Network pharmacology

The weak density of properly d-r. e. branching degree in the d-r.e. degrees

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Science China Mathematics 1999年第7期42卷 691-698页

作者：陆宏丁德成 department of Mathematics Nanjing University Nanjing China

It is proved that for any r.e. degreesv re exists a properly d-r.e. degreec such thatc is a branching degree andv

关键词： recursion theory d.r.e. degrees branch.

Break-up Process of Perturbed Molten Metal Jet and Preparation of Lead-Free Solder Balls

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Journal of rare Earths 2004年第Z2期22卷 174-177页

作者： He Lijun Zhang Shuguang Zhang Shaoming Xu Jun Shi Likai National Engineering research Center for Non-Ferrous Metals Composites General Research Institute for Non-Ferrous MetalsBeijing 100088China

Solder balls, which are used in advanced electronics packages such as BGA (Ball Grid Array) and CSP (Chip Scale Package) to substitute the leads and realize the electrical and mechanical connections between substrate and chip,have severe specifications in diameter tolerance, roundness and surface quality, and therefore challenge the traditional technologies for fabrication of metallic particles and powders. The present work made a survey of perturbed molten metal jet break-up process, observed the formation and growth of capillary wave of tin-lead melt jet by way of rapid solidification, and on the basis of the above research, successfully obtained tin-lead eutectic and Sn-4.0Ag-0.5Cu lead free solder balls with tight distribution and good sphericity of particles through optimization of processing parameters, forming a solid base for cost effectively producing solder balls.

关键词： solder balls jet break-up capillary wave perturbation

Influence of Carbon Nanofiber Addition on Mechanical Properties and Crystallization Behavior of Polypropylene

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Journal of Materials Science & technology 2005年第5期21卷 686-690页

作者： Xin TONG Yong CHEN Huiming CHENG Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of SciencesShenyang 110016 China Materials Science & Engineering College Shenyang Ligong University Shenyang 110168 China

Carbon nanofiber （CNF）-reinforced polypropylene （CNF/PP） composites with different CNF contents were prepared by melt mixing, and the mechanical properties and crystallization behavior of the CNF/PP composites obtained were investigated. It was found that the tensile modulus of the composites was increased with the addition of CNFs, but their elongation at break and fracture strain energy were decreased, while the tensile strength of the composites was firstly increased and then decreased due to the agglomeration of CNFs at higher loading. Nonisothermal crystallization analysis showed that the CNFs played a role as nucleating agent in PP matrix, which led to increment in the crystallization rate and the degree of crystallinity of PP. Moreover, X-ray diffraction studies showed that the CNFs incorporated in the PP matrix favored the growth of （040）-oriented PP crystals. With the increase in the CNF content, the nucleating and orientation roles of the CNFs were obviously enhanced.

关键词： Carbon nanofibers Composites Mechanical properties Crystallization behavior

Enhancement Effect of Gold Nanoparticles on the Bioactivity of Hydrogen-producing Microbe

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Journal of Wuhan University of technology(Materials Science) 2006年第4期21卷 16-18页

作者：刘光臻 Institute of Chemistry Chinese Academy of Sciences Beijing 100080China

In order to increase the yield of hydrogen production for hydrogen-producing microbe, the enhancement effect of nanometer- sized gold panicles on the activity of hydrogen-producing microbe was studied. The yields of hydrogen production in the system added by gold nanoparticles of 6 nm and 12 nm in diameter were obviously increased by about 17% and 9% in contrast to that in blank system. The experimental restdts indicate that gold nanoparticles could significantly enhance the bioactivity of hydrogen-producing microbe.

关键词： gold nanoparticles bioactivity hydrogen-produeing microbe

An improved optimal elemental method for updating finite element models

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Earthquake Engineering and Engineering Vibration 2004年第1期3卷 67-74页

作者：段忠东 Spencer B.F. 闫桂荣欧进萍 School of Civil Engineering Harbin Institute of Technology department of Civil and Environmental Engineering University of Illinois at Urbana-Champaign

The optimal matrix method and optimal elemental method used to update finite element models may not provide accurate *** situation occurs when the test modal model is incomplete,as is often the case in *** improved optimal elemental method is presented that defines a new objective function,and as a byproduct,circumvents the need for mass normalized modal shapes,which are also not readily available in *** solve the group of nonlinear equations created by the improved optimal method,the Lagrange multiplier method and Matlab function fmincon are *** deal with actual complex structures, the float-encoding genetic algorithm(FGA)is introduced to enhance the capability of the improved *** examples,a 7- degree of freedom(dOF)mass-spring system and a 53-dOF planar frame,respectively,are updated using the improved method. The example results demonstrate the advantages of the improved method over existing optimal methods,and show that the genetic algorithm is an effective way to update the models used for actual complex structures.

关键词： model updating optimal elemental method Lagrangc multiplier method genetic algorithm

Luminescence properties of nitride red phosphor for LEd

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Journal of rare Earths 2008年第5期26卷 652-655页

作者：滕晓明庄卫东胡运生黄小卫 National Engineering research Center for rare Earth Materials General Research Institute for Non-Ferrous Metals and Grirem Advanced Materials Co. Ltd.

Eu^2＋-doped ternary nitride phosphor, Sr2Si5N8：Eu^2＋, was synthesized using the high temperature solid-state method. The X-ray diffraction （Xrd） pattern showed that Sr2Si5N8 single phase was obtained. The lattice parameters shrank because the radius of Eu^2＋ was smaller than that of Sr^2＋. The emission spectra showed a broad emission band. With an increase in Eu^2＋ concentration, the emission peak position was redshifted. The excitation spectra showed two excitation bands originating from the host and the 4f^7→4f^6 5d^1 transition of Eu^2＋ ions Compared with the luminescent characteristic of Sr2Si5N8：Eu^2＋ and CaS：Eu^2＋ phosphors, at different temperatures, it was noted that the intensity of the two phosphors reduced gradually with an increase in temperature. The intensity of Sr2Si5N8：Eu^2＋ phosphor was stronger than that of CaS：Eu^2＋, which indicated that the luminescent characteristic of the former was better than that of the latter.

关键词： luminescence alkaline earth nitride white LEds rare earths

A monolithic 3.1-4.8 GHz MB-OFdM UWB transceiver in 0.18-μm CMOS

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Journal of Semiconductors 2010年第6期31卷 109-117页

作者：郑仁亮江旭东姚望杨光尹江伟郑剑钦任俊彦李巍李宁 State Key Laboratory of ASIC and System Fudan University Micro-/Nano-Electronics Science and technology Innovation Platform Fudan University

A monolithic rF transceiver for an MB-OFdM UWB system in 3.1-4.8 GHz is *** transceiver adopts direct-conversion architecture and integrates all building blocks including a gain controllable wideband LNA,a I/Q merged quadrature mixer,a fifth-order Gm-C bi-quad Chebyshev LPF/VGA,a fast-settling frequency synthesizer with a poly-phase filter,a linear broadband up-conversion quadrature modulator,an active d2S converter and a variablegain power *** ESd protected transceiver is fabricated in Jazz Semiconductor＇s 0.18-μm rF CMOS with an area of 6.1 mm^2 and draws a total current of 221 mAfrom 1.8-V *** receiver achieves a maximum voltage gain of 68 dB with a control range of 42 dB in 6 dB/step,noise figures of 5.5-8.8 dB for three sub-bands,and an inband /out-band IIP_3 better than-4 dBm/＋9 *** transmitter achieves an output power ranging from-10.7 to-3 dBm with gain control,an output P_（1dB） better than-7.7 dBm,a sideband rejection about 32.4 dBc,and LO suppression of 31.1 *** hopping time among sub-bands is less than 2.05 ns.

关键词： MB-OFdM UWB transceiver receiver transmitter synthesizer

Optimization design of the stratospheric airship's power system based on the methodology of orthogonal experiment

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2013年第1期14卷 38-46页

作者： Jian LIU Quan-bao WANG Hai-tao ZHAO Ji-an CHEN Ye QIU deng-ping dUAN School of Aeronautics and Astronautics Shanghai Jiao Tong University

The optimization design of the power system is essential for stratospheric airships with paradoxical requirements of high reliability and low weight. The methodology of orthogonal experiment is presented to deal with the problem of the optimization design of the airship's power system. Mathematical models of the solar array, regenerative fuel cell, and power management subsystem (PMS) are presented. The basic theory of the method of orthogonal experiment is discussed, and the selection of factors and levels of the experiment and the choice of the evaluation function are also revealed. The proposed methodology is validated in the optimization design of the power system of the ZhiYuan-2 stratospheric airship. results show that the optimal configuration is easily obtained through this methodology. Furthermore, the optimal configuration and three sub-optimal configurations are in the Pareto frontier of the design space. Sensitivity analyses for the weight and reliability of the airship's power system are presented.

关键词： Stratospheric airship Power system Orthogonal experiment Optimization

Synthesis and luminescence properties of Sr_(3-z)(Al_xSi_(1-x))O_(5-x)F_x:zCe^(3+) phosphors

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Journal of rare Earths 2013年第7期31卷 665-668页

作者：马小乐庄卫东郭汉杰刘荣辉刘元红何华强彭鹏陈磊 National Engineering research Center for rare Earth Materials General Research Institute for Nonferrous Metalsand Grirem Advanced Materials Co.Ltd. School of Metallurgical and Ecological Engineering University of Science and Technology Beijing

Sr3-z（AlxSi1-x）O5-xFx：zCe^3＋ phosphors were synthesized by high-temperature solid-state reaction. The structure and lumi- nescence properties of phosphors with various A1/Si ratios and Ce3＋ concentrations were characterized using various methods such as X-ray diffraction, photoluminescence excitation and photoluminescence spectra. Xrd result displayed that a complete solid solution between Sr3AlO4F and Sr3SiO5 was formed. With the increasing ofx value, a broader excitation band and stronger absorption appeared in the blue light region. Moreover, the emission band shifted to a shorter wavelength and the emission intensity reached a maximum at x=0.6. By adjusting the concentration of Ce3＋, a widely tunable range of emission wavelength under the excitation of 460 um was obtained from the green to yellow regions. In addition, the concentration and thermal quenching were also discussed.

关键词： luminescence solid solution thermal quenching concentration quenching rare earths