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EXPERIMENTS AND SIMULATIONS OF A NEW DEVELOPED FORMING TECHNOLOGY-SHEAR-EXTRUSION PROCESS OF COMPONENTS WITH BRANCHES

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Acta Metallurgica Sinica(english Letters) 2001年第3期14卷 212-218页

作者： H.L. yang, D.C. Kang, z.L. zhang, X.H. Piao and z.D. Shi (National Die and Mold CAD engineering Research Center, Shanghai Jiaotong University, Shanghai 200030, China) (School of Materials Sci. & eng., Harbin Institute of Technology, Harbin 150001, China) National Die and Mold CAD engineering Research Center Shanghai Jiaotong University School of Materials Sci. & eng. Harbin Institute of Technology

Shear-extrusion process and its forming parameters are proposed, whilst its laborsaving characteristic is utilized to forge large-size shutoff valve bodies on the middle-due press. This new process is intended for the manufacture of large-size forged tubular components with branches on the middle-due press. Experiments are carried out and processing parameters are obtained regarding the shear- extrusion process of a large-size shutoff valve body. Deformation and metal flow in the shear- extrusion process are investigated. In order to verify the laborsaving characteristic of this new process, some contrast experiments of extrusion force are performed between shear-extrusion and upsetting-extrusion for forming tubular components with branches. Based on rigid-plastic FEM, a plane-strain model is established to analyze shear-extrusion process of tubular components with branches. The analysis results by 2-dimensions FEM are comparatively well consistent with experimental results. Both simulated and experimental results show that this new forming process is feasible for forging large-size tubular components with branches on the middle-due press.

关键词： Metal extrusion Shearing Simulation Tubular steel structures

Performace of a Kind of Organic Emulsion Coated Phosphogypsum Particles

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Journal of Wuhan University of Technology(Materials Science) 2020年第5期35卷 872-878页

作者： CH eng Jiangguo zHANG Je XIE Fei zHANG Yusong College of Materials and Metallurgy Guizhou University Guiyvang 550025China Mining College Guizhou UniversityGuiyang 550025China Guizhou Key Laboratory of Comprehensive Utilization of Nonmetallic Mineral Resources Guiyang 550025China

The phosphogypsum particles coated with organic emulsion were prepared by coating three kinds of organic emulsion of silicone-acrylic,styrene-acrylic and *** structure and mineralogical characteristics,acid and alkali resistance,water resistance and dissociation degree of coated phosphogypsum were studied by means of SEM-EDAX,optical microscope,gravimetric analysis and chemical *** results showed that the initial emulsion can be used directly for coating and granulation of *** spray re-coating was carried out by using diluted emulsion with the water-to-emulsion mass ratio of 1∶*** organic emulsion coated phosphogypsum crystal can be clearly observed,and the mixing zone at internal boundary between the organic emulsion and phosphogypsum crystal was distinguishable under the optical *** photos showed that the surface of coated phosphogypsum particles was *** the basic elements of C,O,S and Ca can be detected by *** emulsion can be solidified into film-network between the phosphogypsum crystals inside of the coated particles,and it can play a protective role in improving the acid resistance,alkali resistance and water resistance of phosphogypsum,and reduce the degree of dissociation of phosphogypsum in water.

关键词： organic emulsion phosphogypsum coating particle resistance to acid and alkali

The Electromagnetic Compatibility and Distribution of Antenna System

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Journal of Systems engineering and Electronics 1995年第1期6卷 65-72页

作者： B. F Wang S. z. adns & Y. L. Yao(Dept. of Elect. eng., Beijing University of Aeronautics and Astronatutics, Beijing 100083) Dept. of Elect. eng. Beijing University of Aeronautics and Astronatutics Beijing 100083

The mathematical model of electromagnetic compatibility and the distribution of aircraft antenna system have been investigated. The solutions of the antenna gain and electromagnetic interference margin in the regions of low frequency, resonance and high frequency were discussed. By using the basic analytical method of the EMI margin the distributed antenna system can be determined. The main program flow chart of distributed antenna design were given, and illustrated with examples of the microstrip antennas.

关键词： Electromagnetic compatibility Distribution of antennas Aircraft antennas Microstrip Antennas

Assessing the kinetic model of hydro-distillation and chemical composition ofAquilaria malaccensis leaves essential oil

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Chinese Journal of Chemical engineering 2017年第2期25卷 216-222页

作者： Mahtab Samadi zurina zainal Abidin Robiah Yunus Dayang Radiah Awang Biak Hiroyuki Yoshida eng Hai Lok Department of Chemical and Environmental engineering Faculty of EngineeringUniversity Putra MalaysiaserdangSelangorDaml Ehsan 43400Malaysia Aerospace Manufacturing Research Centre(AMRC) Level 7Tower BlockFaculty of EngineeringUniversity Putra Malaysia43400 5erdang SelangorMalaysia Forest Research Institute Malaysia 52109 Kepong5elangorDarul EhsanMalaysia

This study aimed to model the kinetic of hydro-distillation of Aquilaria malaccensis leaves oil in order to understand and optimize the extraction process. In addition, this study, for the first time, aimed to identify the chemical compositions of the A. rnalaccensis leave-oil. By assessing both first-order kinetic model and the model of simultaneous washing and diffusion, the result indicated that the model of simultaneous washing and diffusion better describes the hydro-distillation mechanism of the essential oil from A. rnalaccensis leaves. The optimum time, solid to liquid ratio, and the heating power for extracting the highest amount of essential oil were found to be around 3 h, 1：10 （g. ml-1）, and 300 W respectively. Yellow essential oil with a strong smell and a yield of 0.05 v/w was extracted by hydro-distillation Clevenger apparatus. Chemical compounds of the essential oil were analyzed using gas chromatography-mass spectroscopy （GC/MS）, which resulted in identification of 42 compounds that constitute 93% of essential oil. Among the identified components, Pentadecanal （32.082%）, 9-Octadecenal, （z）（15.894%）, and Tetradecanal （6.927%） were the major compounds. Considering the fact that all the identified major components possess pesticidal properties, A. malaccensis leaves can be regarded as a promising natural source for producing pesticides.

关键词： Aquilaria malaccensisEssential oilHydro-distillationOptimizationKinetic modeling

EFFECTS OF SPUTTERING CONDITIONS OF Tb Fe Co MAGNETO OPTICAL FILM ON KERRR OTATION

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Acta Metallurgica Sinica(english Letters) 1999年第4期12卷 630-632页

作者： X.Y.zhang , z.N.Liu , J.Yi and z.W.Chen Dept.of Materials eng.,Southwest Jiaotong University,Chengdu 610031 ,China

In the practical magneto opticaldisk productionline,alloysputteringtargetisalwaysusedtosputter recording film , whileinlaid targetisrarely used .In ourlaboratory,a seriesof al loy targets forsputtering magneto- optical recording film were prepared and theeffect ofcomposition andsputtering parameterson magneto opticalpropertiesarestudied . Thesputter ing rateof Al,Siand Tb Fe Co( Mo) undertheconditionsof differentsputtering powerandN2 Argasflux weredetermined and baseontheresults,a variablecomposition andthickness of SiNcan beobtained by meansof regulating sputtering power and gasflux, kindsof Mosputtering filmsareobtained under differentsputtering power and gasflux, and Kerrloop lineofthese magneto opticalfilmsare measuredto acquiretheir propertiessuch as Kerrrota tion,then ,theeffectofsputteringtechnology on Kerrrotationisdiscussed .

关键词： magneto optical disk film magneto optical material

Effect of formulation of alginate beads on their mechanical behavior and stiffness

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Particuology 2011年第3期9卷 228-234页

作者： eng-Seng Chan Tek-Kaun Lim Wan-Ping Voo Ravindra Pogaku Beng Ti Tey zhibing zhang School of engineering Monash University Jalan Lagoon Selatan 4~150 Bandar Sunway 5elangor Malaysia Centre of Materials and Minera/s School of Engineering and Information Technology Universiti Malaysia Sabah 88999 Kota Kinabalu Sabah Malaysia Department of Chemical and Environmental engineering Faculty of Engineering Universiti Putra Malaysia 43400 Serdang Selangor Malaysia School of Chemical engineering University of Birmingham Edgbaston Birmingham BI5 27Z United Kingdom

The aim of this work was to determine the effect of formulation of alginate beads on their mechanical behavior and stiffness when compressed at high speed. The alginate beads were formulated using different types and concentrations of alginate and gelling cations and were produced using an extrusiondripping method, Single wet beads were compressed at a speed of 40 mm/min, and their elastic limits were investigated, and the corresponding force versus displacement data were obtained. The Young＇s moduli of the beads were determined from the force versus displacement data using the Hertz＇s contact mechanics theory. The alginate beads were found to exhibit plastic behavior when they were compressed beyond 50% with the exception of copper-alginate beads for which yield occured at lower deformation, Alginate beads made of higher guluronic acid contents and gelling cations of higher chemical affinity were found to have greater stiffness. Increasing the concentration of alginate and gelling ions also generated a similar effect. At such a compression speed, the values of Young＇s modulus of the beads were found to be in the range between 250 and 900 kPa depending on the bead formulation.

关键词： Algioate Young's modulus Elastic limit Deformation Compression Hertz theory

S100钙结合蛋白B在骨性关节炎软骨损伤修复中的作用及机制研究

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中国修复重建外科杂志 2018年第11期32卷 1429-1434页

作者：朱立帆周建新曾金才张晓剑沈鹏程翁峰标苏州市吴江区第一人民医院南通大学附属吴江医院骨科江苏吴江215200

目的探讨S100钙结合蛋白B(S100B)在骨性关节炎(osteoarthritis,OA)软骨损伤修复中的作用及机制。方法取20只新西兰兔随机分为对照组和模型组,每组10只。模型组兔右膝关节制动法制备软骨损伤模型,对照组不作任何处理。4周后采用ELISA法... 详细信息

目的探讨S100钙结合蛋白B(S100B)在骨性关节炎(osteoarthritis,OA)软骨损伤修复中的作用及机制。方法取20只新西兰兔随机分为对照组和模型组,每组10只。模型组兔右膝关节制动法制备软骨损伤模型,对照组不作任何处理。4周后采用ELISA法检测关节液IL-1β、TNF-α水平,实时荧光定量PCR(real-time fluorescence quantitative PCR,qRT-PCR)和Western blot检测软骨组织S100B、FGF-2、FGF受体1(FGF receptor 1,FGFR1)基因及蛋白表达。分离培养人滑膜成纤维细胞(synovial fibroblasts,SF),观察过表达、干扰S100B以及拮抗FGFR1对细胞IL-1β和TNF-α水平(ELISA法)以及FGF-2和FGFR1基因(qRT-PCR检测)和蛋白(Western blot检测)表达的影响。结果 ELISA检测示模型组兔关节液中IL-1β和TNF-α表达水平均明显高于对照组(P<0.05);qRT-PCR和Western blot检测示,模型组兔软骨组织S100B、FGF-2、FGFR1 mRNA和蛋白表达量均显著高于对照组(P<0.05)。过表达和干扰S100能够分别显著升高和降低脂多糖(lipopolysaccharides,LPS)诱导的IL-1β和TNF-α水平及FGF-2和FGFR1 mRNA和蛋白表达,差异均有统计学意义(P<0.05)。而拮抗FGFR1能够显著降低LPS诱导的IL-1β和TNF-α水平及FGF-2和FGFR1 mRNA和蛋白表达,差异均有统计学意义(P<0.05)。结论 S100B能够调节SF炎性反应并可能影响OA软骨损伤修复,其机制可能与激活FGF-2/FGFR1信号通路有关。

关键词： S100钙结合蛋白B 滑膜成纤维细胞骨性关节炎软骨损伤 FGF-2 FGF受体1

The Research on Adaptive Control Modeling of a Liquid Fertilizer Spreader

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engineering（科研） 2010年第2期2卷 113-117页

作者： z.D. yang 不详

This paper describes a general modeling and control approach for steering wheel variable rate liquid fertilizer applicator. An adaptive numerical modeling approach for describing the system input-output dynamics is proposed, and an optimal control that accounts for the control hardware limits is developed. Field tests have demonstrated the effectiveness of the theoretical development.

关键词： Adaptive Control Variable Rate Fertilizer Precision Agriculture Optimal Control Manure Spreader

The effects of exercise on cognition in Parkinson’s disease: a systematic review

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Translational Neurodegeneration 2014年第1期3卷 21-33页

作者： Danielle K Murray Matthew A Sacheli Janice J eng A Jon Stoessl Pacific Parkinson’s Research Centre and Department of Medicine Division of NeurologyUniversity of British Columbia&Vancouver Coastal HealthVancouverBC V6T 2B5Canada Department of Physical Therapy University of British ColumbiaVancouverBC V6T 1Z3Canada

Cognitive impairments are highly prevalent in Parkinson’s disease(PD)and can substantially affect a patient’s quality of *** impairments remain difficult to manage with current clinical therapies,but exercise has been identified as a possible *** objective of this systematic review was to accumulate and analyze evidence for the effects of exercise on cognition in both animal models of PD and human *** systematic review was conducted according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses(PRISMA)*** original reports were identified,including six pre-clinical animal studies and eight human clinical *** studies used various exercise interventions and evaluated many different outcome measures;therefore,only a qualitative synthesis was *** evidence from animal studies supports the role of exercise to improve cognition in humans through the promotion of neuronal proliferation,neuroprotection and *** findings warrant more research to determine what roles these neural mechanisms play in clinical *** reports on cognitive changes in clinical studies demonstrate that a range of exercise programs can improve cognition in *** each clinical study demonstrated improvements in a marker of cognition,there were limitations in each study,including non-randomized designs and risk of *** Grading of Recommendations Assessment,Development and Evaluation(GRADE)system was used and the quality of the evidence for human studies were rated from“low”to“moderate”and the strength of the recommendations were rated from“weak”to“strong”.Studies that assessed executive function,compared to general cognitive abilities,received a higher GRADE ***,this systematic review found that in animal models exercise results in behavioral and corresponding neurobiological changes in the basal ganglia related to *** clinical studies showed that various types of exerc

关键词： Parkinson’s disease Exercise Cognition Humans Animals