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Effect of Injection Velocity on Structure Part characteristic in AZ50 Die casting Process with High Vacuum System

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Journal of Materials Science & Technology 2008年第1期24卷 75-79页

作者： S.M.lee P.k.Seo c.G.kang korea School of Mechanical Engineering Pusan National University Busan 609-735

When diecasting large and thin Mg alloy parts,material defects occur,which include porosity,nonuniform mechanical properties,irregular surfaces,and incomplete *** resolve these problems,it is necessary to have uniform injection velocities and temperatures as well as control the *** study investigated the feasibility of producing large and thin components using a die caster by attaching a high vacuum *** particular,the effects of injection velocity on surface quality and the mechanical properties of the products were ***,an injection velocity scheme and a die structure capable of casting in a vacuum were *** a result,it was found that the critical low injection velocity was 0.2 m/s to produce large thin Mg alloy structures having good mechanical properties.

关键词： Mg die casting Injection velocity Vacuum system

Degree-Based Entropy Descriptors of Graphenylene Using Topological Indices

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computer Modeling in Engineering & Sciences 2023年第10期137卷 939-964页

作者： M.c.Shanmukha Sokjoon lee A.Usha k.c.Shilpa Muhammad Azeem Department of Mathematics Bapuji Institute of Engineering&TechnologyDavanagere577004India Department of computer Engineering(Smart Security) Gachon UniversitySeongnam13120South Korea Department of Mathematics Alliance School of Applied MathematicsAlliance UniversityBangalore562106India Department of computer Science and Engineering Bapuji Institute of Engineering&TechnologyDavanagere577004India Department of Mathematics Riphah Institute of Computing and Applied SciencesRiphah International UniversityLahore54660Pakistan

Graph theory plays a significant role in the applications of chemistry,pharmacy,communication,maps,and aeronautical *** molecules of chemical compounds are modelled as a graph to study the properties of the *** geometric structure of the compound relates to a few physical properties such as boiling point,enthalpy,π-electron energy,andmolecular *** article aims to determine the practical application of graph theory by solving one of the interdisciplinary problems describing the structures of benzenoid hydrocarbons and *** topological index is an invariant of a molecular graph associated with the chemical structure,which shows the correlation of chemical structures using many physical,chemical properties and biological *** study aims to introduce some novel degree-based entropy descriptors such as ENTSO,ENTGH,ENTHG,ENTSS,ENTNSO,ENTNReZ1,ENTNReZ2 and ENTNSS using the respective topological ***,the above-mentioned entropy measures and physico-chemical properties of benzenoid hydrocarbons are fitted using linear regression models and calculated for graphenylene structure.

关键词： Topological descriptors weighted entropy graphenylene

Prevalence of transfusion transmissible infections among various donor groups:A comparative analysis

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World Journal of Virology 2025年第1期14卷 108-117页

作者： Sanjay k Thakur Anil k Sinha Santosh k Sharma Aarzoo Jahan Dinesh k Negi Ruchika Gupta Sompal Singh Regional Blood Transfusion centre Hindu Rao Hospital and NDMC Medical CollegeNorth Delhi 110007DelhiIndia Department of Zoology Veer Kunwar Singh UniversityAra 802301BiharIndia Regional Blood Transfusion centre and Pathology Hindu Rao Hospital and NDMC Medical CollegeNorth Delhi 110007DelhiIndia Department of cytopathology ICMR-National Institute of Cancer Prevention and ResearchNoida 201301Uttar PradeshIndia

BAckGROUND Transfusion transmissible infections(TTIs)are illnesses spread through contaminated blood or blood *** India,screening for TTIs such as hepatitis B virus(HBV),hepatitis c virus(HcV),human immunodeficiency virus(HIV)-I/II,malaria,and syphilis is mandatory before blood ***,HcV,HBV,and HIV are the leading viruses causing mortality,affecting millions of people globally,including those with co-infections of HIV/HcV and HIV/*** highlight the impact of TTIs on life expectancy and health risks,such as liver cirrhosis,cancer,and other diseases in individuals with chronic ***,millions of blood donations take place annually,emphasizing the importance of maintaining blood *** To study the prevalence of TTIs,viz.,HBV,HcV,HIV I/II,syphilis,and malaria parasite(MP),among different blood donor *** The study assessed the prevalence of TTIs among different blood donor groups in Delhi,*** included total donors,in-house donors,total camp donors,institutional camp donors,and community camp *** for HIV,HBV,and HcV were done using enzyme-linked immunosorbent assay,while syphilis was tested with rapid plasma reagins and MP rapid card *** prevalence of HBV,HcV,HIV,and syphilis,expressed as *** in infection rates between the groups were analyzed usingχ²tests and P-values(less than 0.05).RESULTS The study evaluated TTIs among 42158 blood donors in *** overall cumulative frequency of TTIs in total blood donors was 2.071%,and the frequencies of HBV,HcV,HIV-I/II,venereal disease research laboratory,and MP were 1.048%,0.425%,0.221%,0.377%,and 0.0024%,***-house donors,representing 37656 donors,had the highest transfusion transmissible infection(TTI)prevalence at 2.167%.Among total camp donors(4502 donors),TTIs were identified in 1.266%of donors,while community camp donors(2439 donors)exhibited a prevalence of 1.558%.Institutional camp donors(2063 donors)had the l

关键词： Blood donors Transfusion transmissible infections Hepatitis B virus Human immunodeficiency virus Hepatitis c virus Malaria parasite Syphilis

Microstructural characteristics of Underwater Shock consolidated Aluminum composites

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Journal of Materials Science & Technology 2003年第4期19卷 341-345页

作者： k.Raghukandan k.Hokamoto J.S.lee A.chiba B.c.Pai Department of Mechanical Engineering and Materials Science Kumamoto UniversityKumamotoJapanShock Wave and Condensed Matter Research Center2-39-1 KurokamiKumamoto UniversityKumamotoJapanGraduate studentGraduate School of Science and TechnologyKumamoto UniversityKumamotoJapanDepartment of Mechanical Engineering and Materials ScienceKumamoto UniversityKumamotoJapanRegional Research LaboratoryThiruvananthapuramKeralaIndia

Metal matrix composites (MMcs) offer extra strength and high temperature capabilities in comparison with unrein-forced metals. Aluminum composites possess higher stiffness, strength, fatigue properties and low weight advantages. carbon fiber reinforced Al composites (Al-cf) and silicon carbide particulate reinforced Al composites (AI-Sicp) were shock densified using axisymmetric assemblies for underwater explosions. Unidirectional planar shock waves were applied to obtain uniform consolidation of the composites. The energy generator was a high explosive of 6.9 km/s detonation velocity. Irregular morphological powders of Al were the base material. The reinforcement ratio was 15 Vol. pet for Al-cf composites and 30 Vol. pet for AI-Sicp composites. The microstructural and the strength characteristics of the shock consolidated Al composites are reported.

关键词： Shock consolidation Aluminum composites Microstructure Strength characteristics

cold plasma redistribution throughout geospace

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Science china(Technological Sciences) 2016年第9期59卷 1340-1345页

作者： Foster john c. Massachusetts Institute of Technology Haystack Observatory

The redistribution of the electrically charged cold plasma of ionospheric origin involves the equatorial,low,mid,auroral,and polar-latitude regions in a multi-step,system-wide process linking the regions of *** with ground and space-based instruments characterize the geospace plume-regularly occurring channels of enhanced plasma density flowing at both ionospheric and magnetospheric *** in the SAPS channel transports the eroded material to the noontime cusp in the ionosphere and to the dayside magnetopause at high *** the fluxes of cold plume plasma traverse the cusp and enter the polar cap,they form the polar tongue of *** the cusp the plume plasma provides a rich source of heavy ions for the magnetospheric injection and acceleration via the mechanisms operative on those field lines.

关键词： plasmasphere ionosphere geospace GPS TEc ionospheric electric field plume

A case Study of Heat Transfer from Hot Runner Mould to the Fix Platen of the Injection-moulding Machine

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厦门大学学报（自然科学版） 2002年第S1期41卷 97-98页

作者： c H Tan k S lee School of Mechanical & Manufacturing Engineering Department of Mechanical Engineering National University of Singapore Singapore Polytec hnic SingaporeSingapore

In an injection moulding process, the parallelism b et ween the tie bars of the injection moulding machine is very important as it will affect the mould closing and clamping system. In recent years, more and more ho t runner systems are being applied in the moulding industry to save material and decrease the losses of injection pressure. Heat transfer from hot runner system from the fixed half which is secured in the fix machine platen could transmit s o much heat that it may cause high temperature differential between the machine fix platen and moving platen. This will cause the tie bar to become unparallel. Part quality will be compromised and the wear of the tie bar will be excessive. Overhaul of the tie bar may be necessary after a short period of time which is c ostly. This raises the need to analyze the heat transfer from the hot runner sys tem to the machine fix platen and the methods of isolating or minimizing the hea t transfer. In this case study, a photo lens article mould was used. The mould w as built with a direct hot runner nozzle system. Heat conduction from hot runner and machine screw to machine fix platen were studied based on either using high temperature heat insulating plate put in placed between the mould and the mould ing machine fix platen or drill cooling channels in the front mould clamping pla te. The high temperature insulator is very costly as it is made out of glass re inforced polymer composite material. Experimental results were obtained and anal yzed to find the best method to minimize the unwanted heat transfer using the ch eapest and most effective method.

关键词： injection moulding cooling hot runner system i njection moulding machine platen tie bar

Two-plasmon-decay instability stimulated by dual laser beams in inertial confinement fusion

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Matter and Radiation at Extremes 2025年第1期10卷 48-56页

作者： c.-W.Lian Y.Ji R.Yan J.Li L.-F.Wang Y.-k.Ding J.Zheng Department of Modern Mechanics University of Science and Technology of ChinaHefeiAnhui 230026China collaborative Innovation center of IFSA Shanghai Jiao Tong UniversityShanghai 200240China Department of Plasma Physics and Fusion Engineering University of Science and Technology of ChinaHefei 230026China Institute of Applied Physics and computational Mathematics Beijing 100088China

Two-plasmon-decay instability(TPD)poses a critical target preheating risk in direct-drive inertial confinement *** this paper,TPD collectively driven by dual laser beams consisting of a normal-incidence laser beam(Beam-N)and a large-angle-incidence laser beam(Beam-L)is investigated via particle-in-cell *** is found that significant TPD growth can develop in this regime at previously unexpected low laser intensities if the intensity of Beam-L exceeds the large-angle-incidence *** beams contribute to the growth of TPD in a“seed-amplification”manner in which the absolute instability driven by Beam-L provides the seeds that are convectively amplified by Beam-N,making TPD energetically important and causing significant pump depletion and hot-electron generation.

关键词： laser pump decay

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植物凝集素类受体激酶研究进展

热带亚热带植物学报 2025年第1期33卷 107-120页

作者：熊圭 john Seymour HESLOP-HARRISON 刘青植物多样性与特色经济作物全国重点实验室广东省应用植物学重点实验室中国科学院华南植物园广州510650 中国科学院大学北京100049 莱斯特大学遗传学和基因组生物学系英国莱斯特LE17RH 华南国家植物园广州510650

植物凝集素类受体激酶(lectin receptor-like kinases, LecRLks),隶属于植物膜蛋白类受体激酶,LecRLks主要由胞外凝集素结构域、跨膜结构域和胞内激酶结构域组成,根据胞外结构域的特异性,分为G型、L型和c型,凝集素类受体激酶参与植物的... 详细信息

植物凝集素类受体激酶(lectin receptor-like kinases, LecRLks),隶属于植物膜蛋白类受体激酶,LecRLks主要由胞外凝集素结构域、跨膜结构域和胞内激酶结构域组成,根据胞外结构域的特异性,分为G型、L型和c型,凝集素类受体激酶参与植物的生长发育和环境响应调控。该文总结凝集素类受体激酶的研究历史、结构和分类,阐述植物LecRLks的发育调控和胁迫响应功能,对功能明确的LecRLks基因进行归类。提出凝集素类受体激酶研究中存在的不足之处,包括该家族演化历史研究极其缺乏、信号传导途径及其潜在配体亟待开展等方面。在此基础上,提出未来深入研究的方向,以期为植物凝集素类受体激酶基因家族的定向育种提供理论支持。

关键词：凝集素类受体蛋白激酶生长发育生物/非生物胁迫免疫

comparison of Flux-Switching Machines With and Without Permanent Magnets

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chinese Journal of Electrical Engineering 2015年第1期1卷 78-84页

作者： christopher H.T.lee k.T.chau c.c.chan Department of Electrical and Electronic Engineering The University of Hong KongHong KongChina

In this paper,three advanced flux-switching(FS)machines,namely the radial-field flux-switching permanent-magnet(RF-FSPM)machine,the radial-field flux-switching Dc-field(RF-FSDc)machine,and the axial-field FSDc(AF-FSDc)machine are quantitatively *** the installation of the high-energy-density PM materials,the RF-FSPM machine can definitely provide the superior torque performances as compared to its magnetless ***,the PM machines suffer from two major fundamental problems,namely the high material costs,and the uncontrollable flux *** utilizing the concept of axial-field structure,the AF-FSDc machine can offer comparable torque performance as the RF-FSPM ***,with the consideration of the cost-effectiveness and the control flexibility,the magnetless AF-FSDc machine has exhibited promising potential in various applications.

关键词： Flux-switching magnetless radial-field axial-field cost-effectiveness