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Journal of Geriatric Cardiology 2024年第2期21卷 246-250页

作者： Shu-Yu MENG li-qun wang Hao-Dan DANG lin ZHANG Sheng-li JIANG Bo-Han liU Department of Ultrasound Diagnosis the First Medical CenterChinese PLA General HospitalBeijingChina Department of Nuclear Medicine the First Medical CenterChinese PLA General HospitalBeijingChina Department of Pathology the First Medical CenterChinese PLA General HospitalBeijingChina Department of Cardiovascular Surgery the First Medical CenterChinese PLA General HospitalBeijingChina

Paragangliomas,also known as pheochromocytomas(1–9 cases per million),arise in the paraganglia.[1]Pheochromocytomas occur in the adrenal glands,while paragangliomas occur elsewhere.[2]Paragangliomas originate from paraganglion cells,which are derived from the neural ectoderm of the nerves and migrate along both sides of the median axis from the base of the skull to the pelvis during embryonic development.

关键词： glioma cardiac nerves

Dynamic mechanical characteristics of NdFeB in electromagnetic brake

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Defence Technology（防务技术） 2023年第1期19卷 111-125页

作者： Lei li Guo-lai Yang li-qun wang School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing210094JiangsuChina

With the continuous development of artillery,the disadvantages of hydraulic recoil brakes gradually *** the same time,the appearance of high-performance Nd Fe B permanent magnet makes it possible to apply electromagnetic braking technology to recoil *** this paper,prototype tests of a certain artillery were carried out to verify the feasibility of the electromagnetic brake(EMB)and obtain the electromagnetic braking *** to the brittleness of Nd Fe B,in order to eliminate the worry about the safety of EMB,SHPB experiments of Nd Fe B were carried ***,based on the assumption of uniform crack distribution,the law of crack propagation and damage accumulation was described theoretically,and the damage constitutive model suitable for brittle materials was proposed by combining the Zhu-wang-Tang(ZWT)***,the numerical simulation model of the artillery prototype was established and through calculation,the dynamic mechanical characteristics of Nd Fe B in the prototype were *** calculation results show that the strength of Nd Fe B can meet the requirements of the use in the working *** the perspective of damage factor,the damage value of the permanent magnet on the far right is larger,and the damage value of the inner ring gradually decreases to the outer ring.

关键词： Electromagnetic brake Sintered NdFeB Damage constitutive Dynamic mechanical characteristics

Interval uncertain optimization for damping fluctuation of a segmented electromagnetic buffer under intensive impact load

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Defence Technology（防务技术） 2021年第3期17卷 884-897页

作者： Zi-xuan li Guo-lai Yang Feng-jie Xu li-qun wang School of Mechanical Engineering Nanjing University of Science and TechnologyNanjingPR China

Aiming at the problems of demagnetization effect of electromagnetic buffer(EMB)caused by high velocity under intensive impact load and the difficulty and error of machining composite thin-walled long tube,a segmented EMB is *** inner tube and air-gap are divided into initial segments and the traversing *** theoretical analysis,impact test and simulation,it can be found that the RRF curve has two ***,in order to reduce the resultant resistance force(RRF)peaks,the sensitivity analysis based on optimal Latin hypercube design(OLHD)and polynomial regression was *** results show that the smallest contribution ratio to the dynamic response is the seventh and ninth segments of the inner tube,which are less than 1%.Then,fully considering the uncertain factors,important parameters are selected for uncertain optimization after sensitivity *** interval order and interval probability degree methods are used to establish interval uncertain optimization model of the RRF considering *** model was solved using an interval nested optimization method based on radial basis function(RBF)neural ***,the Pareto front is obtained and numerical simulation is performed to verify the optimal *** indicates that the two kinds of RRF peak is obviously reduced,and the optimization object and strategy are effective.

关键词： EMB Intensive impact load Segmented Sensitivity analysis Interval uncertain Optimization

Phase Transition and Micellization of Temperature Responsive Dextran-graft-poly (N-isopropylacrylamide) Polymers

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Chinese Chemical Letters 2003年第4期14卷 407-410页

作者： li qun wang Ke Hua TU Yu Ping li Jie ZHANG Department of Polymer Science and Engineering Zhejiang UniversityHangzhou 310027

Phase behavior and micellization of dextran-graft-poly (N-isopropylacrylamide) (PNIPAAm) polymers in aqueous solution are investigated in this paper using DSC and AFM methods. It is found that with the increase of grafting (G%) of the copolymers the endothermic enthalpy during the phase transition increases significantly and the transition temperature decreases slightly. The phase transition behavior of the copolymers is scanning rate dependent. Micelles are formed whenever the solution temperature is raised above the LCST of the copolymers. It is proposed that by using this thermal responsive property of the copolymers, drugs could be incorporated into the micelles without employing any organic solvent.

关键词： Dextran, graft copolymers thermosensitive LCST.

The Mixed-Mode Fatigue Crack Propagation Model of Piezoelectric Materials Under Electric Fatigue Loading by the Jk-Integral

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Acta Mechanica Solida Sinica 2024年第4期37卷 634-641页

作者： Xianghua Chen Chunguang wang qun li The Institute of Xi’an Aerospace Solid Propulsion Technology Xi’an710025China State Key Laboratory for Strength and Vibration of Mechanical Structures School of Aerospace EngineeringXi’an Jiaotong UniversityXi’an710049China

The electric fatigue load has a significant effect on the crack propagation behavior and failure life of piezoelectric materials and devices. In this paper, an electrical mixed-mode fatigue crack propagation model for piezoelectric materials is proposed based on the piezoelectric Jk-integral theory. The crack initiation, propagation, and life prediction criteria of piezoelectric materials under electric fatigue loading are given by this model, and the finite element simulation model is established to study the electrical mixed-mode crack propagation behavior of piezoelectric structures. Meanwhile, the electrical mixed-mode fatigue crack propagation model is applied to the fatigue crack propagation behavior of a piezoelectric typical defective structure, the crack–hole interference model. The mixed-mode crack propagation, fatigue life, and the interference behavior between the crack and hole at various hole locations of the crack–hole interference model are well recognized by this model. The crack propagation behavior under different electrical load intensities is also considered. The results show that the hole in front of the crack tip inhibits crack propagation to a certain extent, and the strength of electrical load affects the fatigue life of piezoelectric materials and structures. Therefore, the proposed electrical mixed-mode fatigue crack propagation model provides a reference for predicting the mixed-mode fatigue crack propagation behavior and fatigue life of piezoelectric structures under electric fatigue loading.

关键词： Configurational force J k-integral Piezoelectric Mixed-mode crack propagation life prediction

Design of an L1 band low noise single-chip GPS receiver in 0.18 μm CMOS technology

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The Journal of China Universities of Posts and Telecommunications 2010年第3期17卷 60-65页

作者： CHEN Ying-mei li Zhi-qun wang Zhi-gong JING Yong-kang ZHANG li Institute of Radio Frequency and Electronic Integrated Circuits Southeast University Nanjing 210096 China

This article presents an L1 band low noise integrated global positioning system （GPS） receiver chip using 0.18 μm CMOS technology. Dual-conversion with a low-IF architecture was used for this GPS receiver. The receiver is composed of low noise amplifier （LNA）, down-conversion mixers, band pass filter, received signal strength indicator, variable gain amplifier, programmable gain amplifier, ADC, PLL frequency synthesizer and other key blocks. The receiver achieves a maximum gain of 105 dB and noise figure less than 6 dB. The variable gain amplifier （VGA） and programmable gain amplifier （PGA） provide gain control dynamic range over 50 dB. The receiver consumes less than 160 mW from a 1.8 V supply while occupying a 2.9 mm2 chip area including the ESD I/O pads.

关键词： CMOS RF receiver GPS low IF satellite communications wireless communications

Study on Thermosensitive Micellization of Dextran-g-PNIPAAm in Aqueous Solutions

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Chinese Chemical Letters 2006年第6期17卷 837-840页

作者： Dan ZHAO li qun wang Ke Hua TU Song Wei TAN Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027

The thermosensitive micellization of dextran-g-PNIPAAm in aqueous solutions has been investigated by fluorescence spectroscopy, dynamic light scattering and transmission electron microscope. The formed polymeric micelles showed different diameters of about 20 nm or 100 nm, when the solution temperature was below or above the phase transition temperature.

关键词： Amphiphiles micelles poly(N-isopropylacrylamide) thermosensitive copolymers.

Temperature-pH Sensitive IPN Hydrogels Composed of Silk Sericin and Poly(N-isopropylacrylamide)

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Chinese Chemical Letters 2006年第3期17卷 403-406页

作者： Wen WU Wen Jing li li qun wang Ke Hua TU Wei lin SUN Deparment of Polymer Science and Engineering Zhejiang University Hangzhou 310027 Ningbo Institute of Technology Zhejiang University Ningbo 315100

Interpenetrating polymer network （IPN） composed of silk sericin （SS） and poly（N-isopropylacrylamide）（PNIPAAm） was prepared. The morphology of the IPNs, in which the SS phase was stained with ammonium cuprate, was examined with TEM and a relative homogeneous distribution of the two polymers was exhibited. The swelling behavior of the IPN hydrogels showed both temperature and pH dependences.

关键词： Silk sericin poly(N-isopropylacrylamide) interpenetrating polymer network.

Ibuprofen induced drug loaded polymeric micelles

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Chinese Chemical Letters 2011年第9期22卷 1123-1126页

作者： Song Wei Tan Hong Jun wang Ke Hua Tu Hong liang Jiang li qun wang MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and Engineering Zhejiang UniversityHangzhou 310027 China

Three model drugs with different function groups were chosen to dialyze with dextran-graft-poly （N-isopropylacrylalaide）. Only ibuprofen could induce the formation of drug loaded micelles, which was contirmed with dynamic light scattering and transmission electron microscope. Hydrogen-bonding between the amide groups of poly （N-isopropylacrylamide） and the carboxyl groups of ibuprofen was driving force for the drug-loaded micelle. It was also found thai the diameter of the ibuprofen-loaded micelles changed reversibly against temperature.

关键词： Micellc Thernlo-sensilive Drug Hydrogen-bonding Poly (N-isopropylacryhlmide)

Warm Deformation Behavior of Steels Containing Carbon of 0.45% to 1.26% With Martensite Starting Structure

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Journal of Iron and Steel Research International 2010年第5期17卷 34-37页

作者： li qun wang Tian-sheng li Hong-biao GAO Yu-wei liNing JING Tian-fu State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004 Hebei China

Warm deformation was investigated for steels containing carbon of 0. 45%,0. 79%, and 1. 26% respeetively with martensite starting structure, using Gleeble 3500 thermomechanical simulator at the temperature ranging from 873 K to 973 K and the strain rate ranging from 0.1 s^-1 to 0. 001 s^-1. The effect of carbon content on the deformation activation energy, Z value and the deformation resistance was analyzed, The results showed that the deformation resistance decreased with increasing carbon content. The peak stress of the steel containing earbon of 1.26% was decreased by 16.2% compared to the steel containing carbon of 0.45% under the same condition. This may be attributed to the weakening effect of solid solution strengthening which outweighs the precipitation strengthening of cementite.

关键词： carbon steel martensite starting structure warm deformation deformation resistance