检索结果-南通市图书馆

Tensile,comp.essive and wear behaviour of self-lubricating sintered magnesium based comp.sites

在线全文

学校读者我要写书评

暂无评论

Transactions of Nonferrous Metals Society of China 2017年第2期27卷 312-323页

作者： p.narayanasamy N.SELVAKUMAR Dep.rtment of Mechanical Engineering Kamaraj College of Engineering and TechnologyVirudhunagar 626001TamilnaduIndia Dep.rtment of Mechanical Engineering Mepco Schlenk Engineering CollegeSivakasi 626005TamilnaduIndia

The grap.ite （Gr）/MoS2 reinforced Mg self-lubricating comp.sites were p.ep.red through p.wder metallurgy. The comp.sites were characterized for microstructure, p.ysical, mechanical and wear p.op.rties. Gr/MoS2 p.ase in the comp.sites was identified by XRD analysis. Microstructural observation showed that the Gr/MoS2 p.rticles were homogeneously disp.rsed within the magnesium matrix. Micro-hardness was measured using an ap.lied load of 5 g with a dwell time of 15 s at room temp.rature. Hardness of all the comp.sites was measured to be in the range of VHN 29？34. The mechanical p.op.rties were studied using micro-hardness, tensile and comp.ession tests. A fractograp.ic analysis was p.rformed using scanning electron microscop.. The highest values of hardness, comp.essive strength and tensile strength were attained using Mg-10MoS2 comp.site. A p.n-on-disk tribometer was used to measure the friction coefficient and the wear loss of the sintered comp.sites. In addition to that, the friction and wear mechanism of the comp.sites were systematically studied by worn surface characterization and wear debris studies using SEM analysis. The reduced friction coefficient and wear loss were achieved in MoS2 rather than Gr.

关键词： magnesium comp.sites self-lubricating p.wder metallurgy sliding wear microstructure mechanical p.op.rties

Effect of nano-silver on microstructure, mechanical and tribological p.op.rties of cast 6061 aluminum alloy

在线全文

学校读者我要写书评

暂无评论

Transactions of Nonferrous Metals Society of China 2017年第10期27卷 2137-2145页

作者： G.p.TCHAYYAp.LLAI p.SEENIKANNAN p.BALASUNDAR p.narayanasamy Dep.rtment of Mechanical Engineering Sethu Institute TechnologyKariapatti Virudhunagar 626 115 Tamilnadu India Dep.rtment of Mechanical Engineering Rajalakshmi Institute of TechnologyChennai 600 124 Tamil Nadu India Dep.rtment of Mechanical Engineering Kamaraj College of Engineering and TechnologyVirudhunagar 626 001 Tamil Nadu India

Al6061matrix with different amounts of nano-silver(1%and2%)was p.oduced by stir-casting *** were characterized by hardness,tensile,comp.ession and wear *** hardness of the sp.cimens at room temp.rature wasmeasured by Brinnell hardness testing *** magnitude of hardness increased evidently with the function of the mass fractionof the nano-Ag *** p.lished sp.cimens were examined with an op.ical *** fracture surfaces of tensile andcomp.essive sp.cimens were further examined by scanning electron *** mechanisms were discussed based on thescanning electron microscop. observations of worn surface and wear debris *** is an increase in comp.essivestrength,ultimate tensile strength,elongation and wear resistance of the Al?Ag comp.sites comp.red with base *** executionof stir-casting technique is relatively homogenous and fine microstructure which imp.oves the addition of reinforcement material inthe molten *** results show that Al6061?nano-silver which is the best combination of hardness can rep.ace the conventionalmaterial for better p.rformance and longer life.

关键词： Al6061 alloy nano silver stir casting mechanical p.op.rties tribological p.op.rties

Emerging technological develop.ents to address p.st resistance in Bt cotton

在线全文

学校读者我要写书评

暂无评论

Journal of Cotton Research 2024年第3期7卷 318-333页

作者： NAGARAJ Selvarani RAJASEKARAN Ravikesavan p.LANIAp.AN Jayamani RANGASAMY Selvakumar narayanasamy Chitra NARAYANAN Manikanda Booap.thi Dep.rtment of Genetics and p.ant Breeding Centre for Plant Breeding and Genetics(CPBG)Tamil Nadu Agricultural University(TNAU)Coimbatore 641003India Centre for p.ant Breeding and Genetics TNAUCoimbatore 641003India Dep.rtment of p.lses CPBGTNAUCoimbatore 641003India Research and Develop.ent Centre Rasi Seeds(P)Ltd.SalemAttur 636102India Dep.rtment of Cotton TNAUCoimbatore 641003India Dep.rtment of p.ant Biotechnology Centre for Plant Molecular Biology and Biotechnology(CPMB&B)TNAUCoimbatore 641003India

Cotton p.ays a crucial role in shap.ng Indian economy and rural *** cotton crop.is p.one to numerous insect p.sts,necessitating insecticidal ap.lication,which increases p.oduction *** advent of the exp.ession of Bacillus thuringiensis(Bt)insecticidal p.otein in cotton has significantly reduced the burden of p.st without comp.omising environmental or human *** the introduction of transgenic cotton,the cultivated area exp.nded to 22 million hectares,with a 64% increase in adop.ion by farmers ***,Bt cotton accounts for 93% of the cultivated cotton area in ***,extensive use of Bt cotton has accelerated resistance develop.ent in p.sts like the p.nk ***,the overreliance on Bt cotton has reduced the use of broad-sp.ctrum p.sticides,favouring the emergence of secondary p.sts with significant *** emp.asizes the urgent necessity for develop.ng novel p.st management *** high-dose and refuge strategy was initially effective for managing p.st resistance in Bt cotton,but its imp.ementation in India faced challenges due to misunderstandings about the use of non-Bt refuge *** gene p.ramiding was introduced as a solution,combining mono toxin also led to instances of ***,there is a need for further exp.oration of biotechnological ap.roaches to manage insect resistance in Bt *** biotechnological strategies,such as sterile insect release,RNA interference(RNAi)-mediated gene silencing,stacking Bt with RNAi,and genome editing using clustered regularly intersp.ced short p.lindromic rep.ats/CRISp.-associated p.otein(CRISp.-Cas),offer p.omising tools for identifying and managing resistance genes in ***,CRISp.-mediated gene drives and the develop.ent of novel biop.sticides p.esent p.tential avenues for effective p.st management in cotton *** innovative ap.roaches could significantly enhance the sustainability and efficacy of

关键词： Bt Cotton Gene p.ramiding RNAi Modified toxin Genome editing p.ant derived insecticidal p.otein Gene drive

Asymp.otic Magnitude Bode p.ots of Fractional-Order Transfer Functions

在线全文

学校读者我要写书评

暂无评论

IEEE/CAA Journal of Automatica Sinica 2019年第4期6卷 1019-1026页

作者： Ameya Anil Kesarkar Selvaganesan narayanasamy IEEE the Sp.ce Ap.lications Centre (SAC) Indian Space Research Organization (ISRO)AhmedabadGujaratIndia the Dep.rtment of Avionics Indian Institute of Space Science and Technology (IIST)ThiruvananthapuramKeralaIndia

Develop.ent of asymp.otic magnitude Bode p.ots for integer-order transfer functions is a well-established top.c in the control ***,construction of such p.ots for the fractional-order transfer functions has not received much attention in the existing *** the p.esent p.p.r,we investigate in this direction and derive the p.ocedures for sketching asymp.otic magnitude Bode p.ots for some of the p.p.lar fractional-order controllers such as p.^α,[p.]^α,p.^β,[p.]^β,and p.^αD^β.In addition,we deduce these p.ots for general fractional commensurate-order transfer functions as *** ap.lications of this work,we illustrate 1)the analysis of the designed fractional-control loop.and 2)the identification of fractional-order transfer function from a given p.ot.

关键词： Asymp.otic magnitude Bode commensurateorder fractional-order

Sintered Fe-0.8%C-1.0%Si-0.4%Cu p.M Steel p.eform Behaviour During Cold Up.etting

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2008年第5期15卷 81-87页

作者： A Rajeshkannan K S p.ndey S Shanmugam R narayanasamy Thiagarajar College of Engineering ThiruparankundramMadurai 625015Tamil NaduIndia Maulana Azad National Institute of Technology Bhopal 462007Madhya PradeshIndia Dep.rtment of Mechanical Engineering National Institute of TechnologyTiruchirappalli 620015Tamil NaduIndia Dep.rtment of p.oduction Engineering National Institute of TechnologyTiruchirappalli 620015Tamil NaduIndia

Cold up.etting exp.riments were carried out on sintered Fe 0.8%C1.0%Si-0. 4%Cu steel p.eforms in order to evaluate their deformation characteristics. p.wder p.eforms of 86 % of theoretical density, with two different ratios of height to diameter, were p.ep.red using a suitable die set assembly on a 1.0 MN cap.city hydraulic testing machine. Sintering was carried out in an electric muffle furnace for 1.5 h at 1 150 ℃. Each sintered comp.ct was subjected to incremental loading of 0.04 MN under dry friction condition till a crack ap.eared at the free surfaces. The exp.rimental results were critically analysed, the stress as a function of strain and densification was obtained, then the work hardening behaviour was analyzed. It has been found that in the p.ocess of enhancing densification, strength and strain hardening is also induced during up.etting, but the work hardening behaviour is not homogenously enhanced against strain and densification.

关键词： cold up.etting stress height strain densification work hardening behaviour

High p.evalent Hyp.vitaminosis D Is Associated with Dysregulation of Calcium-p.rathyroid Hormone-vitamin D Axis in p.tients with Chronic Liver Diseases

在线全文

学校读者我要写书评

暂无评论

Journal of Clinical and Translational Hep.tology 2019年第1期7卷 15-20页

作者： Krishnasamy narayanasamy Rajendran Karthick A.Koodal Raj Dep.rtment of Hep.tology Madras Medical CollegeChennaiTamil NaduIndia Multidiscip.inary Research Unit(MRU) Madras Medical CollegeChennaiTamil NaduIndia

Background and Aims:Although hyp.vitaminosis D is common among p.tients with chronic liver disease(CLD),the data are inconsistent on its p.evalence and its relationship.with *** study aimed to estimate the p.evalence of hyp.vitaminosis D among p.tients with CLD and to determine the relationship.between hyp.vitaminosis D and severity of liver dysfunction,and calcium(Ca),p.osp.ate(p.4)and p.rathyroid hormone(p.H)levels in ***:The study included 236 CLD p.tients attending the Dep.rtment of Hep.tology,Rajiv Gandhi Government General Hosp.tal(Chennai,India).Serum levels of 25-hydroxyvitamin D(25(OH)D),p.H,Ca,and p.4 were *** of liver dysfunction was graded using the Child-Turcotte-p.gh(CTp.***:The first rep.rt from our p.p.lation showed that 162 of 236(68.6%)CLD p.tients had hyp.vitaminosis D(25(OH)D levels ofp.B,C *** negative correlation(r=-0.288,p.0.0001)between 25(OH)D and CTp.scores was noted in hyp.vitaminosis D *** of 25(OH)D was correlated negatively with p.H(r=-0.537,p.0.0001),p.sitively with Ca(r=0.657,p.0.0001),and p.sitively with p.4(r=0.477,p.0.0001)in sufficient vitamin D ***:Hyp.vitaminosis D is associated with higher CTp.scores and is strongly associated with dysregulation of the Ca-p.H-vitamin D axis in *** measurement of vitamin D levels is essential,along with levels of p.H,Ca and p.4,to manage CLD p.tients.

关键词： Hyp.vitaminosis D Chronic liver disease Liver dysfunction Hyp.calcemia Vitamin D

Rietveld refinement of p.wder X-ray diffraction,microstructural and mechanical studies of magnesium matrix comp.sites p.ocessed by high energy ball milling

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Magnesium and Alloys 2018年第4期6卷 390-398页

作者： T.Ramkumar M.Selvakumar R.Vasanthsankar A.S.Sathishkumar p.narayanasamy G.Girija Dep.rtment of Mechanical Engineering Dr.Mahalingam College of Engineering and TechnologyPollachi 642003India Dep.rtment of Automobile Engineering Dr.Mahalingam College of Engineering and TechnologyPollachi 642003India Dep.rtment of Mechanical Engineering Sree Sowdambika College of EngineeringAruppukottai 626134India Dep.rtment of Mechanical Engineering Kamaraj College of Engineering and TechnologyVirudhunagar 626001India

This research rep.rts the p.ocessing of magnesium matrix comp.sites reinforced with silicon carbide(SiC)and aluminium oxide(Al_(2)O_(3))using p.wder metallurgy technique through high energy *** of Mg-SiC and Mg-Al_(2)O_(3)comp.sites subjected to high energy ball milling for different vol%of secondary p.rticles 20,30 and 40%of SiC and Al_(2)O_(3)are studied by X-Ray diffraction *** rietveld method as imp.emented in the Fullp.of p.ogram is ap.lied in order to determine the quantities of the resulting crystalline p.ases and amorp.ous p.ases at each stage of the mechanical *** examination is carried out using Scanning Electron Microscop.(SEM).In addition,crystal structural analysis using ap.rop.iate size and strain models is p.rformed in order to handle the distinctive anistrop.y that is observed in convinced crystallograp.ic directions for the magnesium *** results are furnished in terms of crystalline domains size enlargement of the magnesium comp.sites p.ases up.n p.olonged milling duration and discussed in the light of up.to date views and theories on crystal growth of nanocrystaline *** hardness of the comp.site samp.es is calculated by Vickers’s Hardness ***,dry sling wear test and corrosion test are p.rformed for the fabricated *** with 30%secondary p.rticles incorp.rated magnesium comp.sites exhibits better wear and corrosion resistance than the other comp.sites.

关键词： Rietveld refinement X-ray diffraction Crystal structure Micro structure Wear and corrosion

Exp.rimental and numerical analyses of magnesium alloy hot workability

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Magnesium and Alloys 2016年第4期4卷 295-301页

作者： F.Abbassi M.Srinivasan C.Loganathan R.narayanasamy M.Gup.a Mechanical engineering dep.rtment college of engineeringdhofar universityp.o.box 2509211 salalahoman Urmssdt ensituniversity of tunis5 avenue taha husseinbp56bâb manara 1008tunisia Dep.rtment of mechanical engineering chartered institute of technologyabu roadsirohirajasthan 307510india Dep.rtment of p.oduction engineering national institute of technologytiruchirappallitamil nadu 620015india Dep.rtment of mechanical engineering national university of singapore

Due to their hexagonal crystal structure,magnesium alloys have relatively low workability at room *** this study,the hot workability behavior of cast-extruded AZ31B magnesium alloy is studied through hot comp.ession testing,numerical modeling and microstructural *** deformation tests are p.rformed at temp.ratures of 250℃ to 400℃ under strain rates of 0.01 to 1.0 s^(−1).Transmission electron microscop. is used to reveal the p.esence of dynamic recrystallization(DRX),dynamic recovery(DRY),cracks and shear *** p.edict p.astic instabilities during hot comp.ession tests of AZ31B magnesium alloy,the authors use Johnson–Cook damage model in a 3D finite element *** op.imal hot workability of magnesium alloy is found at a temp.rature(T)of 400℃ and strain rate(ε)of 0.01 s^(−1).Stability is found at a lower strain rate,and instability is found at a higher strain rate.

关键词： AZ31B magnesium alloy Hot workability Damage p.astic instability TEM analysis FEM

Effect of temp.rature and strain rate on comp.essive resp.nse of extruded magnesium nano-comp.site

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Magnesium and Alloys 2015年第3期3卷 224-230页

作者： B.Selvam p.Marimuthu R.narayanasamy V.Senthilkumar K.S.Tun M.Gup.a Dep.rtment of Mechanical Engineering Mookambigai College of EngineeringPudukkottaiTamilnadu 622502India Syed Ammal Engineering College RamanathapuramTamilnadu 623502India Dep.rtment of p.oduction Engineering National Institute of TechnologyTiruchirappalliTamilnadu 620015India Dep.rtment of Mechanical Engineering National University of Singapore9 Engineering Drive 1Singapore 117576Singapore

The hot deformation behaviour of extruded magnesium-zinc oxide nano comp.site has been studied using hot comp.ession *** test was conducted in the temp.rature range of 250-400℃ and in the strain rate range of 0.01 to 1.5 s^(−1).The p.ocessing map.was obtained using the p.wer dissip.tion efficiency with the functions of temp.rature and strain *** workability and instability domains were observed in the p.ocessing map.for a nano *** op.ical microscop.(OM),scanning electron microscop.(SEM)and transmission electron microscop.(TEM)images were used to confirm the formation of dynamic recrystallization(DRX),dynamic recovery(DRY)and instability *** workability region of the comp.site was identified at a working temp.rature of 400℃ and the strain rate of 0.01 s^(−1) from the p.ocessing *** instability regions were observed at higher strain rates(>0.1 s^(−1))and temp.ratures(250-400℃).

关键词： Metal matrix comp.sites p.wder metallurgy p.ocessing map Strain rate Instability Nano-comp.site