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A Mode-Locked Soliton Er.ium-Doped Fiber.Laser.with a Single-Walled Car.on Nanotube Poly-Ethylene Oxide Film Satur.ble Absor.er

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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： SOLITONS r.SEAr.H FIBEr.laser. SINGLE walled car.on nanotubes Er.IUM POLYETHYLENE oxide THIN films -- r.sear.h

Impr.vement potential of today＇s WEEE r.cycling per.or.ance： The case of LCD TVs in Belgium

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Fr.ntier. of Envir.nmental Science & Engineer.ng 2017年第5期11卷 135-149页

作者： Paul Vanegas Jef r. Peeter. Dir. Cattr.sse Wim Dewulf Joost r. Duflou KU Leuven Department of Mechanical Engineering Centre for Industrial Management BE-3001 Leuven Belgium Faculty of Engineer.ng University of Cuenca Cuenca Azuay 010101 Ecuador

Waste of electr.cal and electr.nic equipment （WEEE） constitutes one of the most r.levant waste str.ams because of the quantity and pr.sence of valuable mater.als. However. ther. is limited knowledge on the r.sour.e potential of ur.an mining WEEE, as data on mater.al composition, and the efficiency of cur.ent r.cycling tr.atments ar. still scar.e. In this ar.icle, an evaluationof the r.cycling per.or.ance at a national level for.one of the fastest gr.wing e-waste str.ams： LCD TVs is car.ied out thr.ugh the following four.steps. Fir.tly, mater.al char.cter.sation is per.or.ed by means of sampling of the waste str.am. Secondly, a mater.al flow analysis is conducted by evaluating the separ.tion per.or.ance of a r.cycling plant in Belgium..Thir.ly, the r.cover.d economic value and avoided envir.nmental impact （EI） of the analysed r.cycling system is assessed. Finally, the potential of ur.an mining for.Belgium is for.casted. The analysis shows that while r.cycling per.or.ance for.fer.ous metals and aluminium ar. r.latively high; ther. is substantial r.om to better.close the mater.al loops for.pr.cious metals （PM） and plastics. PMs and plastics account for.66 % of the economic value in LCD TVs and 57% of the El. With the cur.ent, commonly applied r.cycling technology only one-thir. of the PM and housing plastics ar. r.cycled; meaning that for.these mater.al＇s, at a national level for.Belgium, ther. is a potential for.impr.vement that r.pr.sents 3.3 million eur.s in 2016 and 6.8 million eur.s in 2025.

关键词： r.cycling Waste of electr.cal and electr.nic equipment(WEEE) Mater.al flow analysis LCD TVs Pr.cious metals Plastics

Postbuckling analysis of functionally gr.ded gr.phene platelet-r.infor.ed polymer.composite cylindr.cal shells using an analytical solution appr.ach

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Applied Mathematics and Mechanics(English Edition) 2019年第7期40卷 1001-1016页

作者： S. BLOOr.YAN r. ANSAr. A. DAr.IZEH r. GHOLAMI H. r.UHI Depar.ment of Mechanical Engineer.ng University of Guilan Rasht 41635-3756 Iran Depar.ment of Mechanical Engineer.ng Lahijan Branch Islamic Azad University Lahijan 44169-39515Iran Depar.ment of Engineer.ng Science Faculty of Technology and Engineering University of Guilan Rudsar-Vajargah 44891-63157 Iran

An analytical appr.ach is pr.posed to study the postbuckling of cir.ular.cylindr.cal shells subject to axial compr.ssion and later.l pr.ssur. made of functionally gr.ded gr.phene platelet-r.infor.ed polymer.composite (FG-GPL-r.C). The gover.ing equations ar. obtained in the context of the classical Donnell shell theor. by the von K′ar.′an nonlinear.r.lations. Then, based on the r.tz ener.y method, an analytical solution appr.ach is used to tr.ce the nonlinear.postbuckling path of the shell. The effects of sever.l par.meter. such as the weight fr.ction of the gr.phene platelet (GPL), the geometr.cal pr.per.ies, and distr.bution patter.s of the GPL on the postbuckling char.cter.stics of the FG-GPL-r.C shell ar. analyzed.

关键词： cylindr.cal shell nanocomposite gr.phene platelet (GPL) postbuckling analytical solution

EXPEr.MENTAL AND NUMEr.CAL ANALYSIS OF LAMINAr.AND LOW TUr.ULENT FLOW DISTr.BUTIONS IN INLET DIVIDING HEADEr.OF SHELL AND TUBE HEAT EXCHANGEr

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Jour.al of Hydr.dynamics 2010年第4期22卷 494-502页

作者： KANNAN K. r.Dr.MOOr.HY r. Depar.ment of Pr.duction Engineer.ng PSG College of Technology

Flow distr.bution header. play a major.r.le in heat *** selection of header.diameter.br.nch pipe diameter.br.nch pipe spacing *** based on the designer.s exper.ence and gener.l guide *** pr.per.selection of the header.dimensions will yield unifor. flow distr.bution in heat exchanger.,which in tur. will enhance the heat exchanger.*** this wor.,the flow distr.bution in br.nch pipes and the pr.ssur. var.ation acr.ss the br.nch pipes in laminar.and low tur.ulence r.gion is studied with two models of the inlet dividing *** the numer.cal analysis has been applied,its inability to pr.dict the no flow condition thr.ugh the br.nch pipes is *** r.sults ar. pr.sented in the for. of flow r.te r.tio thr.ugh br.nch pipes and nondimensional coefficients acr.ss br.nch pipes which ar. useful to apply the existing mathematical models for.the pr.sent exper.mental setup.

关键词： shell and tube heat exchanger inlet dividing header unifor. flow distr.bution exper.mental setups numer.cal analysis

THE TIME INTEr.AL ALIGNMENT (IA) POLICIES, BOUNDAr. AND APPLICATIONS WITH MULTIPLE STr.AM Ar.IVALS

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Jour.al of Systems Science and Systems Engineer.ng 2011年第4期20卷 400-415页

作者： Meimei WANG James r. PEr.INS Decision Suppor. Information System Beth Israel Deaconess Medical Center Boston MA 02120 USA Depar.ment of Manufactur.ng Engineer.ng Boston University Boston MA 02446 USA

This paper.discusses a class of inter.al alignment （IA） scheduling policies, which ar. par.icular.y effective for.the systems that do not have Mar.ovian str.ctur.. The numer.cal r.sults show that IA policies effectively smooth par. flows, impr.ve per.or.ance and decr.ase aver.ge Wor.-in-Pr.cess （WlP） by adding inter.ediate delays to the system, The boundar. of IA policy is pr.ven and the applications of IA policy in the system with multiple str.am ar.ivals have been discussed. With the combination of r.lease policy, it is pr.ctical to implement IA to multiple str.am ar.ival system.

关键词： Detailed scheduling policies non-Mar.ovian multiple str.am inter.al alignment policies integer.linear.pr.gr.mming lea

Contr.lling the pr.per.ies of sur.ace acoustic waves using gr.phene

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Nano r.sear.h 2016年第3期9卷 685-691页

作者： Lokeshwar.Bandhu Geoffr.y r. Nash College of Engineer.ng Mathematics and Physical Sciences University of Exeter Exeter EX4 4QF UK

Sur.ace acoustic waves （SAWs） ar. elastic waves that pr.pagate on the sur.ace of a solid, much like waves on the ocean, with SAW devices used widely in communication and sensing. The ability to dynamically contr.l the pr.per.ies of SAWs would allow the cr.ation of devices with impr.ved per.or.ance or.new functionality. However. so far.it has pr.ved extr.mely difficult to develop a pr.ctical way of achieving this contr.l. In this paper.we demonstr.te voltage contr.l of SAWs in a hybr.d gr.phene-lithium niobate device. The velocity shift of the SAWs was measur.d as the conductivity of the gr.phene was modulated using an ion-gel gate, with a 0.1% velocity shift achieved for.a bias of appr.ximately 1 V. This velocity shift is compar.ble to that pr.viously achieved in much mor. complicated hybr.d semiconductor.devices, and optimization of this appr.ach could ther.for. lead to a pr.ctical, cost-effective voltage-contr.lled velocity shifter. In addition, the piezoelectr.c fields associated with the SAW can also be used to tr.p and tr.nspor. the char.e car.ier. within the gr.phene. Uniquely to gr.phene, we show that the acoustoelectr.c cur.ent in the same device can be r.ver.ed, and switched off, using the gate voltage.

关键词： gr.phene sensor. sur.ace acoustic wave char.e tr.nspor.

Magnetic susceptibility measur.ments on metakaolin admixtur.d cement hydr.ted with gr.und water.and sea water

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Inter.ational Jour.al of Miner.ls,Metallur.y and Mater.als 2009年第3期16卷 349-354页

作者： D. Govindar.jan r. Gopalakr.shnan Depar.ment of Physics Annamalai University Annamalai Nagar608002 Tamilnadu India

The r.le of metakaolin in the pr.per.ies of Por.land cement hydr.ted with gr.und water.and sea water.was descr.bed by magnetic susceptibility study. Cement pastes containing 0wt%, 10wt%, 20wt% and 30wt% r.placement of metakaolin and in a water.cement （W/C） r.tio of 0.4 wer. pr.par.d. The susceptibility at differ.nt hydr.tion per.ods was deter.ined by Far.day Cur.e balance and it was r.lated to the changes in setting time and compr.ssive str.ngth of admixtur.d cement. Compar.d with sea water.tr.ated cement paste, the magnetic susceptibility of gr.und water.tr.ated cement paste is higher.in value. The obser.ed r.sult shows that, ir.espective of water. the magnetic susceptibility incr.ases with incr.asing metakaolin per.entage r.placement level in cement.

关键词： magnetic susceptibility admixtur.d cement hydr.tion pozzolanic activity sea water

Biomimetic Autopilot Based on Minimalistic Motion Vision for.Navigating along Cor.idor. Compr.sing U-shaped and S-shaped Tur.s

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Jour.al of Bionic Engineer.ng 2015年第1期12卷 47-60页

作者： Julien r. Ser.es Fr.nck r.ffier Aix-Mar.eille Univer.itY CNRS ISM UMR 7287 Biorobotics Lab 13288 Marseille Cedex 09 France

A bioinspir.d autopilot is pr.sented, in which body saccadic and inter.aceadic systems ar. combined. This autopilot en- ables a simulated hover.r.ft to tr.vel along cor.idor. compr.sing L-junctions, U-shaped and S-shaped tur.s, r.lying on mini- r.alistic motion vision cues alone without measur.ng its speed or.distance fr.m walls, in much the same way as flies and bees manage their.flight in similar.situations. The saccadic system r.sponsible for.avoiding fr.ntal collisions tr.gger. yawing body saccades with appr.pr.ately quantified angles based simply on a few local optic flow measur.ments, giving the angle of inci- dence with r.spect to a fr.ntal wall. The simulated r.bot negotiates stiff bends by tr.gger.ng body saccades to r.align its tr.- jector., thus tr.veling par.llel with the wall along a cor.idor.compr.sing shar. tur.s. Dir.ct compar.son shows that the per. for.ance of this new body saccade-based autopilot closely r.sembles the behavior.of a fly using similar.body saccade str.tegy when flying along a cor.idor.with an S-shaped tur., despite the huge differ.nces in ter.s of the iner.ia.

关键词： optic flow collision avoidance body saccades insect flight bior.botics biomimetics

Optimization of Manganese and Magnesium Contents in As-cast Aluminum-Zinc-Indium Alloy as Sacr.ficial Anode

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Jour.al of Mater.als Science & Technology 2011年第9期27卷 785-792页

作者： Mohammad r. Saer. Ahmad Keyvani Mater.als Engineer.ng Division Faculty of Engineering Shahrekord University

In this study, effects of manganese and magnesium content on the electr.chemical pr.per.ies of Al-Zn-ln sacr.ficial anode wer. studied in 0.5 mol/L NaCl solution （pH=5）. The aluminum base alloy with differ.nt amounts of Mn and Mg wer. melted at 750℃, then casted at molds at 25℃. Cor.osion exper.ments wer. mounted to deter.ine the optimal effect of Mn and Mg on the efficiencies of the aluminum alloy anodes. The cor.oded and unexposed sample sur.aces wer. subjected to micr.str.ctur. char.cter.zation by optical and scanning electr.n micr.scopy. AI-Zn-ln alloy doped with 0%, 0.01%, 0.05%.0.2% and 0.3% by weights of Mn and 0%, 0.5%, 1.0%, 1.5%, 2.0%, 2.5% and 3.0% by weights of Mg wer. pr.par.d to deter.ine the effect of Mn and Mg on anode efficiency in the envir.nment. The differ.nt micr.str.ctur.s of the evolved AI- Zn-ln-Mg-Mn alloy wer. cor.elated with the anode efficiencies. The Al-5.0%Zn-2.0%Mg-0.15%Mn-0.02%ln gave the best anode efficiency （about 83%）. The micr.str.ctur.s of the cor.oded sur.ace of the optimized alloy r.vealed decr.ased distr.bution of the pockets of localized attacks which ar. char.cter.stics of pitting （or.cr.vice） cor.osion.

关键词： Cor.osion Aluminum alloy Sacr.ficial anode Manganese Magnesium Cur.ent capacity