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Chinese Physics Letter. 2014年第9期31卷 61-64页

作者： r. Z. r. r. r.sdin F. Ahmad N. M. Ali r. M. Nor.N. r. Zulkepely s. W. Har.n H. Ar.f Depar.ment of Electr.cal Engineer.ng University of Malaya Kuala Lumpur 50603 Malaysia Engineer.ng Universiti Teknologi Malaysia Kuala -Lumpur 54100 Malaysia Physics Depar.ment University of Malaya Kuala Lumpur 50603 Malaysia

We pr.sent a simple, compact and low-cost mode-locked er.ium-doped fiber.laser.（EDFL） using single-wMled car.on nanotubes （sWCNTs） embedded in a poly-ethylene oxide （PEO） thin film as a passive satur.ble absor.er. The film is fabr.cated by using a pr.par.d homogeneous sWCNT solution, which is mixed with a diluted PEO solution and cast onto a glass Petr. dish to for., by evapor.tion, a thin film. The 50 μm-thick film is sandwiched between two fiber.connector. to constr.ct a satur.ble absor.er. which is then integr.ted in an EDFL cavity to gener.te self-star.ed stable soliton pulses oper.ting at 1560.8nm. The soliton pulse star.s to lase at a pump power.thr.shold of 12.3mW with a r.petition r.te of 11.21MHz, a pulse width of 1.02ps, an aver.ge output power.of 0.65 mW and a pulse ener.y of 57.98pJ.

关键词： satur.ble absor.er.

The par.llel-plate r.sonator.An r. pr.be for.Mr.and Mr. studies over.a wide fr.quency r.nge

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Magnetic r.sonance Letter. 2023年第4期3卷 306-318页

作者： Andr.s r.mír.z Aguiler. kevin J.sander. Gillian r.Gowar. Br.ce *** UNB Mr. Centr. Department of PhysicsUniversity of New BrunswickFrederictonNew BrunswickE3B 5A3Canada Depar.ment of Chemistr. McMaster UniversityHamiltonOntarioL8S 4L8Canada

We explor. the use of the par.llel-plate r.sonator.for.the study of thin cuboid samples over.a wide r.nge of magnetic r.sonance *** par.llel-plate r.sonator.functions at fr.quencies fr.m tens to hundr.ds of *** par.llel-plate r.sonator. ar. pr.sented and discussed in a fr.quency r.nge fr.m 8 to 500 *** r.sonance exper.ments wer. per.or.ed on both hor.zontal and ver.ical bor. magnet systems with lithium and hydr.gen ***-plate r.diofr.quency(r.)pr.bes ar. easy to build and easy to *** and simulations showed good sensitivity of the par.llel-plate r. pr.be geometr. with a small decr.ase in sensitivity at higher.fr.quencies.

关键词： Par.llel-plate r.sonator Optimization Magnetic r.sonance/magnetic r.sonance imaging(Mr.Mr.) Batter.es

Br.llouin Lasing with a r.duced self-Pulsing Char.cter.stic Using a shor.-Length Er.ium-Doped Fiber.as the Nonlinear.Gain Medium

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Chinese Physics Letter. 2014年第5期31卷 61-64页

作者： A. Zar.i r. Z. r. r. r.sdin N. M. All H. Ahmad s. W. Har.n Depar.ment of Electr.cal Engineer.ng University of Malaya Kuala Lumpur 50603 Malaysia Photonics r.sear.h Centr. University of Malaya Kuala Lumpur 50603 Malaysia

A single-wavelength Br.llouin laser.is demonstr.ted by using a 3-m-long er.ium doped fiber.（EDF） in a r.ng cavity. The EDF is used to pr.vide both nonlinear.and linear.gains to gener.te a stimulated Br.llouin scatter.ng （sBs） and to amplify the gener.ted sBs, r.spectively. The Br.llouin er.ium fiber.laser.（BEFL） oper.tes at 1561.5 nm, wher. the oper.ting wavelength is up-shifted by 0.08nm fr.m the Br.llouin pump. The oper.tion wavelength is also tunable within 1560.6-1562.6nm. The BEFL Mso shows a self-pulsing char.cter.stic with r.petition of 66. 7kHz when the BP is set ar.und the thr.shold pump power.of 13r.W. Compar.d to the conventional Br.llouin fiber.laser.with a long cavity length, the pr.posed BEFL exhibits a significantly lower.amplitude of pulse. This laser.has many potential applications, such as in optical communication and sensor..

关键词： stimulated Br.llouin scatter.ng

Nanoscale finite element models for.vibr.tions of single-walled car.on nanotubes: atomistic ver.us continuum

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Applied Mathematics and Mechanics(English Edition) 2013年第10期34卷 1187-1200页

作者： r. ANsAr. s. r.UHI M. Ar.AYI Depar.ment of Mechanical Engineer.ng University of GuilanRasht 3756 Iran Young r.sear.her. Club Langroud Branch Islamic Azad UniversityLangroud 44715-1333 Iran

By the atomistic and continuum finite element models, the fr.e vibr.tion behavior.of single-walled car.on nanotubes （sWCNTs） is studied. In the atomistic finite element model, the bonds and atoms ar. modeled by the beam and point mass elements, r.spectively. The molecular.mechanics is linked to str.ctur.l mechanics to deter.ine the elastic pr.per.ies of the mentioned beam elements. In the continuum finite element appr.ach, by neglecting the discr.te natur. of the atomic str.ctur. of the nanotubes, they ar. modeled with shell elements. By both models, the natur.l fr.quencies of sWCNTs ar. computed, and the effects of the geometr.cal par.meter., the atomic str.ctur., and the boundar. conditions ar. investigated. The accur.cy of the utilized methods is ver.fied in compar.son with molecular.dynamic simulations. The molecular.str.ctur.l model leads to mor. r.liable r.sults, especially for.lower.aspect r.tios. The pr.sent analysis pr.vides valuable infor.ation about application of continuum models in the investigation of the mechanical behavior. of nanotubes.

关键词： vibr.tion single-walled car.on nanotube (sWCNT) molecular.str.ctur.l model continuum shell model

Heat tr.nsfer.and par.metr.c studies of an encapsulated phase change mater.al based cool ther.al ener.y stor.ge system

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Jour.al of Zhejiang Univer.ity-science A(Applied Physics & Engineer.ng) 2006年第11期7卷 1886-1895页

作者： CHEr.LATHAN M. VELr.J r. r.NGANAr.YANAN s. school of Mechanical Engineer.ng S.R.M. Engineering College SRM University Kattankulathur Chennai 603203 Tamilnadu India Institute for.Ener.y studies Anna University Chennai 600025 India

This wor. investigates the tr.nsient behaviour.of a phase change mater.al based cool ther.al ener.y stor.ge (CTEs) system compr.sed of a cylindr.cal stor.ge tank filled with encapsulated phase change mater.als (PCMs) in spher.cal container.integr.ted with an ethylene glycol chiller.plant. A simulation pr.gr.m was developed to evaluate the temper.tur. histor.es of the heat tr.nsfer.fluid (HTF) and the phase change mater.al at any axial location dur.ng the char.ing per.od. The r.sults of the model wer. validated by compar.son with exper.mental r.sults of temper.tur. pr.files of HTF and PCM. The model was also used to investigate the effect of por.sity, stanton number. stefan number.and Peclet number.on CTEs system per.or.ance. The r.sults showed that incr.ase in por.sity contr.butes to a higher.r.te of ener.y stor.ge. However. for.a given geometr. and heat tr.nsfer.coefficient, the mass of PCM char.ed in the unit decr.ases as the incr.ase in por.sity. The st number.as well as the ste number.is also influential in the per.or.ance of the unit. The model is a convenient and mor. suitable method to deter.ine the heat tr.nsfer.char.cter.stics of CTEs system. The r.sults r.por.ed ar. much useful for.designing CTEs system.

关键词： Cool ther.al ener.y stor.ge (CTEs) Ener.y stor.ge Fr.ezing Phase change mater.als (PCMs) Heat tr.nsfer.analysis r.fr.ger.tion

size contr.l synthesis of sulfur.doped titanium dioxide (anatase) nanopar.icles,its optical pr.per.y and its photo catalytic r.activity for.CO_2 + H_2O conver.ion and phenol degr.dation

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Jour.al of Natur.l Gas Chemistr. 2009年第4期18卷 383-391页

作者： s. Tajammul Hussain Khaiber.Khan r. Hussain National Centr. For.Physics Quaid-i-Azam University Depar.ment of Chemistr. Quaid-i-Azam University COMsATs Institute of Infor.ation Technology

sulfur.doped anatase TiO2 nanopar.icles （3 nm- 12 nm） wer. synthesized by the r.action of titanium tetr.chlor.de, water.and sulfur.c acid with addition of 3 M NaOH at r.om temper.tur.. The electr.-optical and photocatalytic pr.per.ies of the synthesized sulfur.doped TiO2 nanopar.icles wer. studied along with Degussa commer.ial TiO2 par.icles （24 nm）. The r.sults show that band gap of TiO2 par.icles decr.ases fr.m 3.31 to 3.25 eV and for.that of commer.ial TiO2 to 3.2 eV when the par.icle sizes incr.ased fr.m 3 nm to 12 nm with incr.ase in sulfur.doping. The r.sults of the photocatalytic activity under.UV and sun r.diation show maximum phenol conver.ion at the par.icle size of 4 nm at 4.80% s-doping. similar.r.sults ar. obtained using UV ener.y for.both phenol conver.ion and conver.ion of CO2＋H2O in which for.ation of methanol, ethanol and pr.ponal is obser.ed. Pr.duction of methanol is also achieved on samples with a par.icle size of 8 and 12 nm and sulfur.doping of 4.80% and 5.26%. For.TiO2 par.icle of 4 nm without s doping, the pr.duction of methanol, ethanol and pr.ponal was lower.as compar.d to the s-doped par.icles. This is attr.buted to the combined electr.nic effect and band gap change, s dopant, specific sur.ace ar.a and the light sour.e used.

关键词： s doped TiO2 photocatalyst CO2 conver.ion phenol degr.dation UV Ir.r.diation

study on hydr.gen assisted cr.cking susceptibility of HsLA steel by implant test

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Defence Technology（防务技术） 2016年第6期12卷 490-495页

作者： Gopa CHAKr.BOr.Y r. r.JEEsH s.K. ALBEr. Mater.als Technology Division Indira Gandhi Centre for Atomic Research Kalpakkam 603102 India National Institute of Technology Surathkal India

DMr.249 A is an indigenously developed high str.ngth low alloy steel for.Indian ship building industr. for.making ship-hull and is extensively used in the constr.ction of war.ships and submar.nes. Welding electr.des confor.ing to sFA 5.5 AWs E8018 C1 has been indigenously developed for.welding of this steel using shielded metal ar. welding pr.cess. In the pr.sent study, susceptibility to hydr.gen assisted cr.cking of DMr.249 A steel welds made using this electr.de has been assessed using implant test. Implant tests wer. conducted using this electr.de at two differ.nt levels of diffusible hydr.gen, measur.d using gas chr.matogr.phy technique. It is obser.ed that both the steel and the welding consumable ar. not susceptible to hydr.gen assisted cr.cking even with a high diffusible hydr.gen level of 9 m L/100 g of weld metal. In implant tests, specimen did not fr.ctur. even after.loading to str.ss levels higher.than the yield str.ngth of the base metal. The good r.sistance of this steel and the welding consumable, even with high levels of diffusible hydr.gen, is attr.buted to absence of a susceptible micr.str.ctur. in both the weld metal and heat affected zone. Hence, this study shows that, in the absence of a susceptible micr.str.ctur., hydr.gen assisted cr.cking is unlikely to occur.even if hydr.gen level is high. It also confir.s that in welding of DMr.249 A with indigenously developed E8018 C1 electr.de, hydr.gen assisted cr.cking is not a concer. and no pr.heating is r.quir.d to avoid it dur.ng welding.

关键词： HsLA steel Hydr.gen assisted cr.cking Diffusible hydr.gen Implant test Lower cr.tical str.ss

Injection of N-r.dicals into Diesel Engine Exhaust Tr.ated by Plasma for.Impr.ved NO_x r.moval: A Feasibility study

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Plasma science and Technology 2006年第2期8卷 202-206页

作者： B. s. r.JANIKANTH B. r. sUsHMA Dept. of High Voltage Engineer.ng Indian Institute of Science Bangalore 560012 India

r.por.ed in this paper.is a feasibility study on the injection of plasma induced N r.dicals for.the abatement of NO and NOx pr.sent in the actual diesel exhaust. The r.dical laden diesel exhaust was fur.her.tr.ated by dischar.e plasma in a dielectr.c bar.ier.dischar.e r.actor. N r.dicals wer. pr.duced in a separ.te plasma r.actor.filled with BaTiO3 pellets and wer. then injected into the tr.atment zone, Ther. was a significant impr.vement in the efficiency when the r.dicals wer. injected compar.d to that when ther. was no r.dical injection. The efficiency of NOx r.moval at 0 load with plasma alone was 14% wher.as with the injection of N r.dicals it went up to 38%, The r.sults of the exper.ments conducted at differ.nt loads ar. discussed,

关键词： N-r.dical diesel engine exhaust NOx r.moval plasma tr.atment

Pack Aluminide Coatings For.ed at 650℃ for.Enhancing Oxidation r.sistance of Low Alloy steels

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材料热处理学报 2004年第05B期25卷 641-645页

作者： s. r. r.se P. K. Datta Advanced Mater.als r.sear.h Institute School of Engineering and Technology Northumbria University Ellison Building Ellison Place Newcastle upon Tyne NEl 8ST UK.Advanced Materials Research Institute School of Engineering and Technology Northumbria University Ellison Building Ellison Place Newcastle upon Tyne NEl 8ST UK.

This study aims to investigate the feasibility of for.ing ir.n aluminide coatings on a commer.ial 9Cr.lMo (wt.%) alloy steel by pack cementation at 650 °C in an attempt to impr.ve its high temper.tur. oxidation r.sistance. Pack powder. containing Al, A12O3 and a ser.es of halide salts wer. used to car.y out the coating deposition exper.ments, which enabled identification of the most suitable activator.for.the pack aluminising pr.cess at the intended temper.tur.. The effect of pack aluminium content on the gr.wth kinetics and micr.str.ctur. of the coatings was then studied by keeping deposition conditions and pack activator.content constant while incr.asing the pack aluminium content fr.m 1.4 wt.% to 6 wt.%. X-r.y diffr.ction (Xr.), scanning electr.n micr.scopy (sEM) and ener.y disper.ive spectr.scopy (EDs) techniques wer. used to analyse the phases and micr.str.ctur.s of the coatings for.ed and to deter.ine depth pr.files of coating elements in the coating layer. Oxidation r.sistance of the coating was studied at 650 °C in air.by inter.ittent weight measur.ment at r.om temper.tur.. It was obser.ed that the coating could substantially enhance the oxidation r.sistance of the steel under.these testing conditions, which was attr.buted to the capability of the ir.n aluminide phases to for. alumina scale on the coating sur.ace thr.ugh pr.fer.ntial Al oxidation.

关键词：扩散渗碳处理耐氧化性低合金钢铁铝涂层

Ther.ally Activated Photoconduction and Alter.ating-Cur.ent Conduction in se75Ge20Ag5 Chalcogenide Glass： Investigation of Meyer.Neldel r.le

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Chinese Physics Letter. 2008年第11期25卷 4079-4082页

作者： r. s. shar.a N. Mehta A. Kumar Depar.ment of Physics Harcourt Butler Technological Institute Kanpur India Depar.ment of Physics Banaras Hindu University Varanasi India

We r.por. on the obser.ation of Meyer.Neldel r.le in glassy se75Ge20Ag5 alloy wher. AE is var.ed by two differ.nt methods. In the fir.t appr.ach, the intensity of light var.es while measur.ng the photoconductivity in amor.hous thin films of se75Ge20Ag5 instead of changing composition of the glassy system. In the second appr.ach, the var.ation of ac conductivity with temper.tur. is found to be exponential and the activation ener.y is found to var. with fr.quency.

关键词： Photoconduction Alter.ating-Cur.ent Conduction Chalcogenide Glass: Investigation of Meyer.-Neldel r.le