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Ch.na Ocean Engineering 2019年第3期33卷 356-364页

作者： A. sh.neh.azzadeh.h. Ardalan Faculty of Civil Engineering and Transportation University of Isfahan Isfahan Iran Water Research.Institute (WRI) Tehran Iran

In th.s article, th. sediment transport processes in th. Kh.ran strait between th. mainland Iran and Qesh. Island at North.Central Persian Gulf are studied in regional scale in a compreh.nsive manner. Th. objectives of th.s study include defining th. type and origin of th. sediment, th. influencing factors, and th. dominant mode of sediment transport. Four possible scenarios of sediment processes in terms of sediment sources and influential environmental forces are examined. Th. results of th. conceptual and 2D numerical model of MIKE21 applied for th.s purposes indicate th.t th. sediment sources in th. transport processes are mainly provided by th. sediments suspended from th. central and eastern zones of th. strait bed. Oth.r sources including input from rivers do not h.ve direct influence on th. processes. Th. results are applied to th. study of morph.logical ch.nges for engineering applications including th. pattern and amount of deposit in th. Rajaee port approach.ch.nnel and h.rbor basin. Th. pattern and amount of annual sediment deposits in th. approach.ch.nnel predicted by th. model is satisfactory, compatible with.annual dredging records.

关键词： sediment transport morph.dynamics 2D numerical model Persian Gulf Kh.ran strait Rajaee Port

Multi-wavelength.erbium-doped fiber laser using four-wave mixing effect in doped fiber

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Ch.nese Optics Letters 2011年第6期9卷 80-81页

作者： N. s. sh.h.buddin Z. Yusoff h. Ah.ad s. W. h.run Department of Electrical Engineering University of Malaya Faculty of Engineering Multimedia University Ph.tonics Research.Center University of Malaya

We demonstrate a multi-wavelength.erbium-doped fiber laser （EDFL） using erbium gain and four-wave mixing （FWM） effect in a piece of erbium-doped fiber （EDF） with.h.gh.erbium ion concentration. Th. EDF h.s a pump absorption rate of 24.6 dB/m at 979 nm and is bi-directionally pumped by 980-nm laser diodes. FWM effect redistributes th. energy of different oscillating lines and causes multi-wavelength.operation. Th. laser generates more th.n 22 lines of optical comb with.a line spacing of approximately 0.10 nm at th. 1569-nm region using only 1.5-m-long EDF.

关键词： EDF FWM Multi-wavelength.erbium-doped fiber laser using four-wave mixing effect in doped fiber length wave

Recent Progress in th. synth.sis of Polymers Based on Carbon Dioxide

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复旦学报（自然科学版） 2005年第5期44卷 640-641页

作者： h. sugimoto s. Inoue Deparment of Industrial Ch.mistry Tokyo University of Science Tokyo 162-8601 JapanDeparment of Industrial Chemistry Tokyo University of Science Tokyo 162-8601 Japan

Carbon dioxide is th. most fundamental carbon resource indispensable for all living systems including h.man being via ph.tosynth.sis by green plants. On th. oth.r h.nd, ch.mical utilization of carbon dioxide h.s been ... 详细信息

关键词：二氧化碳交互聚合反应环氧化物聚碳酸脂

Genetic evaluation of twenty seed sources of Asparagus racemosus

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Journal of Forestry Research 2011年第1期22卷 39-42页

作者： Parveen A Kumar h. s. Ginwal Division of Genetics and Tree Propagation Forest Research Institute PO IPE Kaulagarh Road Dehradun 248 195 Uttarakhand India

A field trial of 20 seed sources of Asparagus racemosus was conducted at th. Forest Research.Institute, Deh.adun, Uttarakh.nd, India to evaluate th.ir performance of different economic traits. Genotypic variance, ph.notypic variance, genotypic coefficient of variance （GCV） and ph.notypic coefficient of variance （PCV） for number of sh.ots, sh.ot h.igh., sh.ot weigh., number of roots, root length. root diameter and root weigh. were calculated. Maximum genotypic and ph.notypic variance was observed in sh.ot h.igh. among th. sh.ot - related traits and root length.among th. root - related traits. For th. sh.ot h.igh., genotypic variance, ph.notypic variance, genotypic coefficient of variance, ph.notypic coefficient of variance were 231.80, 3924.80, 61.26 and 1037.32, respectively, wh.re th.se of th. root length.were 9.55, 16.80, 23.46 and 41.27, respectively. Th. maximum genetic advance and genetic gain were obtained for sh.ot h.igh. among th. sh.ot-related traits and root length.among th. root-related traits. Index values were developed for all th. seed sources based on th. four most important traits, and Panth.agar （Uttrakh.nd）, Jodh.ur （Rajasth.n）, Deh.adun （Uttarakh.nd）, Ch.ndigarh.（Punjab）, Jammu （Jammu and Kash.ir） and solan （h.mach.l Pradesh., were promising seed sources for root production.

关键词： Asparagus racemosus genetic advance genetic gain h.ritability index selection seed sources

A continuum traffic flow model with.th. consideration of coupling effect for two-lane freeways

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Acta Mech.nica sinica 2011年第2期27卷 228-236页

作者： D.-h. sun G.-h. Peng L.-P. Fu h.-P. h. College of Automation Chongqing University400030 Chongqing China Department of Civil & Environmental Engineering University of Waterloo Waterloo Ontario N2L 3G 1 Canada College of Automation Chongqing University 400030 Chongqing China

A new h.gh.r-order continuum model is proposed by considering th. coupling and lane ch.nging effects of th. veh.cles on two adjacent lanes. A stability analysis of th. proposed model provides th. conditions th.t ensure its linear stability. Issues related to lane ch.nging, sh.ck waves and rarefaction waves, local clustering and ph.se transition are also investigated with.numerical experiments. Th. simulation results sh.w th.t th. proposed model is capable of providing explanations to some particular traffic ph.nomena commonly observable in real traffic flows.

关键词： Two-lane traffic Two delay time scales model Numerical simulation Coupling effect Ph.se transition

Math.matical modeling and full-scale sh.king table tests for multi-curve buckling restrained braces

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Earth.uake Engineering and Engineering Vibration 2009年第3期8卷 359-371页

作者： C. s. Tsai Yungch.ng Lin Wensh.n Ch.n h. C. su Department of Civil Engineering Feng Chia University Taich.ng Chinese Taipei Graduate Institute of Civil and h.draulic Engineering Feng Chia University Taichung Chinese Taipei Department of Water Resources Engineering and Conservation Feng Chia University Taichung Chinese Taipei

Buckling restrained braces （BRBs） h.ve been widely applied in seismic mitigation since th.y were introduced in th. 1970s. h.wever, traditional BRBs h.ve several disadvantages caused by using a steel tube to envelope th. mortar to prevent th. core plate from buckling, such.as： complex interfaces between th. materials used, uncertain precision, and time consumption during th. manufacturing processes. In th.s study, a new device called th. multi-curve buckling restrained brace （MC-BRB） is proposed to overcome th.se disadvantages. Th. new device consists of a core plate with.multiple neck portions assembled to form multiple energy dissipation segments, and th. enlarged segment, lateral support elements and constraining elements to prevent th. BRB from buckling. Th. enlarged segment located in th. middle of th. core plate can be welded to th. lateral support and constraining elements to increase buckling resistance and to prevent th.m from sliding during earth.uakes. Component tests and a series of sh.king table tests on a full-scale steel structure equipped with.MC-BRBs were carried out to investigate th. beh.vior and capability of th.s new BRB design for seismic mitigation. Th. experimental results illustrate th.t th. MC-BRB possesses a stable mech.nical beh.vior under cyclic loadings and provides good protection to structures during earth.uakes. Also, a math.matical model h.s been developed to simulate th. mech.nical ch.racteristics of BRBs.

关键词： buckling restrained brace energy absorption passive control earth.uake energy plasticity model structural control multi-curve BRB

Effect of Radio Frequency Magnetron sputtering Power on structural and Optical Properties of Ti6A14V Th.n Films

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Ph.tonic sensors 2017年第2期7卷 163-170页

作者： Moh.mmed K. Kh.LAF h. F. Al-TAAY Dawood s. ALI Ministry of science and Tech.ology Center of Applied Physics Baghdad Iraq Department of Ph.sics College of Science for Women University of Baghdad Baghdad Iraq Department of Ph.sics College of Education for Pure Sciences University of Anbar Anbar Iraq

In th.s research. th. effects of target sputtering power on th. structure and optical properties of radio frequency （RF） sputtered Ti6A14V films were investigated. Different sputtering RF powers were used to produce different th.cknesses of Ti6A14V th.n films, From th. X-ray diffraction, it was found th.t th. Ti6A14V films h.d polycrystalline cubic and h.xagonal structures and increased films crystallinity and crystalline size with.increasing th. sputtering power. Atomic forces microscopy （AFM） gave us a nanometric film ch.racter, films h.mogeneity, and surfaces rough.ess. A h.gh.r degree of rough.ess and average grain size with.increasing RF power was exh.bited. Band gap and refractive index of Ti6A14V th.n films varied with.sputtering RF powers.

关键词： RF magnetron sputtering Ti6A14V structural properties optical properties.

Reaction dynamics for ph.toproductions of baryon resonances

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Ch.nese Ph.sics C 2009年第12期33卷 1167-1174页

作者： A. h.saka T. h.odo D. Jido h.-Ch. Kim h. Nagah.ro s.I. Nam M. Oka s. Ozaki Rresearch.Center for Nuclear Ph.sics Osaka University Ibaraki 567-0047 Japan Department of Ph.sics Tokyo Institute of Technology Meguro 152-8551 Japan Yukawa Institute for Th.oretical Ph.sics Kyoto University Kyoto 606-8502 Japan Department of Ph.sics Inha University Incheon 402-751 Republic of Korea Department of Ph.sics Nara Women's University Nara 630-8506 Japan Department of Ph.sics Chung-Yuan Christian University Chung-Li 32023 China

Th. study of exotic structure of h.drons is fully ach.eved wh.n reaction dynamics of th. associated h.dron productions is well understood. We employ as th. standard mech.nism th. effective Lagrangian meth.d and investigate several ph.sical observables with.n th. framework. Th. parameters are constrained by microscopic description of h.drons. We discuss ph.toproductions of kaon associated with.th. ground state A（1116） and its resonances A（1405） and A（1520）. In th. former example we emph.size th. meson cloud effect wh.ch.significantly renormalizes th. ph.nomenological parameters, wh.le in th. latter we discuss th. features of th. standard meth.d. Finally we discuss briefly th. N（1535） for th. study of ch.ral symmetry of baryons. production of ηπ associated with.th. nucleon resonance

关键词： ph.toproduction strangeness baryon resonances

Effect of fusion welding processes on tensile properties of armor grade, h.gh.th.ckness, non-h.at treatable aluminium alloy joints

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Defence Tech.ology（防务技术） 2019年第3期15卷 353-362页

作者： K. Vasu h. Ch.lladurai Addanki Ramaswamy s. Malarvizh. V. Balasubramanian Department of Mech.nical Engineering PDPM Indian Institute of Information Technology Design and Manufacturing Jabalpur Madhya pradesh 482005 India Centre for Materials Joining & Research.(CEMAJOR) Department of Manufacturing Engineering Annamalai University Annamalai Nagar -(P.O) Tamil nadu 608002 India

AA5059 is one of th. h.gh.strength.armor grade aluminium alloy th.t finds its applications in th. military veh.cles due to th. h.gh.r resistance against th. armor piercing (AP) th.eats. Th.s study aimed at finding th. best suitable process among th. fusion welding processes such.as gas tungsten arc welding (GTAW) and gas metal arc welding (GMAW) by evaluating th. tensile properties of AA5059 aluminium alloy joints. Th. fracture path.was identified by mapping th. low h.rdness distribution profile (Lh.P) across th. weld cross section under tensile loading. Optical and scanning electron microscopies were used to ch.racterize th. microstructural features of th. welded joints at various zones. It is evident from th. results th.t GTAW joints sh.wed superior tensile properties compared to GMAW joints and th.s is primarily owing to th. presence of finer grains in th. weld metal zone (WMZ) and narrow h.at-affected zone (h.Z). Th. lower h.at input associated with.th. GTAW process effectively reduced th. size of th. WMZ and h.Z compared to GMAW process. Lower h.at input of GTAW process results in faster cooling rate wh.ch.h.nders th. grain growth.and reduces th. evaporation of magnesium in weld metal compared to GMAW joints. Th. fracture surface of GTAW joint consists of more dimples th.n GMAW joints wh.ch.is an indication th.t th. GTAW joint possess improved ductility th.n GMAW joint.

关键词： Gas tungsten arc welding Gas metal arc welding Armor grade aluminium alloy Tensile properties Microh.rdness

species selection in h.rdwoods research. variations in baseline ph.siological responses of select temperate h.rdwood tree species

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Journal of Forestry Research 2013年第2期24卷 285-292页

作者： sh.neka s. Lawson Paula M. Pijut Ch.rles h. Mich.er UsDA Forest service Northern Research Station Hardwood Tree Improvement and Regeneration Center (HTIRC) Purdue University Department of Forestry and Natural Resources UsDA Forest service Northern Research Station Hardwood Tree Improvement and Regeneration Center (HTIRC)

Drough. periods are becoming more extreme worldwide and th. ability of plants to contribute towards atmosph.ric flux is being compromised. Properly functioning stomata provide an exit for water th.t h.s been absorbed by th. roots, funneled into various cell parts, and eventually released into th. atmosph.re via transpiration. By observing th. effects th.t weath.r conditions such.as climate ch.nge may h.ve on stomatal density, distribution, and functioning, it may be possible to elucidate a portion of th. mech.nisms trees use to survive longer periods of water stress. Th.s study analyzed stomatal density （sD）, stomatal conductance （gs ）, CO2 assimilation （A）, instantaneous water-use efficiency （WUEi ）, and transpiration （E） rates in six native tree species in th. Midwestern UsA and sh.wed th.t trees with.n th. same ecotype followed similar trends, but th.t trees with.n th. same family did not wh.n exposed to identical greenh.use conditions. Naturally drough. tolerant tree species demonstrated lower g s and h.gh.r WUEi , wh.le intolerant species h.d h.gh.r sD. Th.s study sh.wed negative or no correlation between sD and g s , A, E, and WUEi and positive correlations between E and A and gs and E.

关键词： drough. water stress stomatal density h.rdwood trees