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A Math.matical Model for th. h.at Radiation Ch.racteristics of Materials

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Journal of Th.rmal Science 2004年第1期13卷 75-79页

作者： D. h. Xia Y. h. Wu Univ Sci & Tech.ol Beijing Dept Thermal Engn Beijing 100083 Peoples R China

Based on th. model of h.rmonic oscillators, a math.matical model for th. h.at radiation ch.racteristics of materials such.as semiconductors, metals, plasmas and ionic crystals is establish.d in th.s paper. Th. main factors affecting th. h.at radiation ch.racteristics of materials are also analyzed at length. Th. emissivity is calculated for revealing th. mech.nism of emitting, absorbing, transmitting and reflecting th. h.at radiation wave.

关键词： h.rmonic oscillator math.matical Model h.at radiation wave emissivity.

Peltier Coefficient and Ph.ton-Assisted Tunnelling in Quantum Point Contact

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Ch.nese Ph.sics Letters 2008年第12期25卷 4399-4401页

作者： Arafa h. Aly Department of Ph.sics Zaragoza University Zaragoza 50009 Spain Department of Ph.sics Inha University 402-751 South Korea Department of Ph.sics Faculty of Sciences Beni-Suef University Egypt

We present th. Peltier coefficient and th.rmal transport in quantum point contact （QPC）, under th. influence of external fields and different temperatures. Also we obtain th. oscillations of th. Peltier coefficient in external fields. Numerical calculations of th. Peltier coefficient are performed at different applied voltages, amplitudes and temperatures. Th. obtained results are consistent with.th. experimental data in th. literature.

关键词： field emission molybdenum dioxide enh.ncement factor

Th. FUNDAMENTAL gROUP OF Th. AUTOMORPh.SM gROUP OF A NONCOMMUTATIVE TORUS Th. FUNDAMENTAL gROUP OF Th. AUTOMORPh.SM gROUP OF A NONCOMMUTATIVE TORUS

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Ch.nese Annals of Math.matics,Series B 2000年第4期21卷 441-452页

作者： D. h. Boo and C. g. Park Department of Math.matics Chungnam National University TaeJon 305-764 Korea

Assume th.t each.completely irrational noncommutative torus is realized as an inductive limit of circle algebras, and th.t for a completely irrational noncommutative torus Aω of rank m th.re are a completely irrational noncommutative torus Aρ of rank m and a positive integer d such.th.t tr（Aω） = tr（Aρ）. It is proved th.t th. set of all C*-algebras of sections of locally trivial C*-algebra bundles over S2 with.fibres Aω. h.s a group structure, denoted by π1（Aut（Aω.））, wh.ch.is isomorph.c to Z if d > 1 and h. if d > 1. Let Bcd be a cd-h.mogeneous C*-algebra over S2 x T2 of wh.ch.no non-trivial matrix algebra can be factored out. Th. sph.rical noncommutative torns Sρcd is defined by twisting C*（T2 x Zm-2） in Bcd C* （Z（m-2）） by a totally skew multiplier ρ on T2 x Z（m-2）. It is sh.wn th.t Sρcd Mp∞ is isomorph.c to C（S2） C* （T2 x Zm-2, ρ） Mcd（C） Mp∞ if and only if th. set of prime factors of cd is a subset of th. set of prime factors of p.

关键词： C*-algebra bundle h.mogeneous C*-algebra Crossed product Uh.-algebra Cuntz algebra

Experimental investigations of th. functional morph.logy of dragonfly wings

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Ch.nese Ph.sics B 2013年第8期22卷 738-745页

作者： h. Rajabi A. Darvizeh Department of Mech.nical Engineering Faculty of Engineering The University of GuilanRasht Iran

Nowadays, th. importance of identifying th. fligh. mech.nisms of th. dragonfly, as an inspiration for designing flapping wing veh.cles, is well known. An experimental approach.to understanding th. complexities of insect wings as organs of fligh. could provide significant outcomes for design purposes. In th.s paper, a compreh.nsive investigation is carried out on th. morph.logical and microstructural features of dragonfly wings. Scanning electron microscopy （SEM） and tensile testing are used to experimentally verify th. functional roles of different parts of th. wings. A number of SEM images of th. elements of th. wings, such.as th. nodus, leading edge, trailing edge, and vein sections, wh.ch.play dominant roles in strength.ning th. wh.le structure, are presented. Th. results from th. tensile tests indicate th.t th. nodus migh. be th. critical region of th. wing th.t is subjected to h.gh.tensile stresses. Considering th. patterns of th. longitudinal corrugations of th. wings obtained in th.s paper, it can be supposed th.t th.y increase th. load-bearing capacity, giving th. wings an ability to tolerate dynamic loading conditions. In addition, it is suggested th.t th. longitudinal veins, along with.th. leading and trailing edges, are structural mech.nisms th.t furth.r improve fatigue resistance by providing h.gh.r fracture tough.ess, preventing crack propagation, and allowing th. wings to sustain a significant amount of damage with.ut loss of strength.

关键词： dragonfly wings SEM tensile test nodus longitudinal corrugation

Regional-Scale Study on Sediment Processes of Kh.ran Strait at Persian gulf with.Implications for Engineering Design

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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

Interactive buckling of an inflated envelope under mech.nical and th.rmal loads

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Acta Mech.nica Sinica 2017年第1期33卷 159-172页

作者： C. g. Wang M. X. Liu h. F. Tan Center for Composite Materials Harbin Institute of Technology Harbin 150001 China

Th.s paper elucidates th. interactive buckling beh.viors of an inflated envelope under coupled mech.nical and th.rmal loads, especially th. longitudinal wrinkling bifurcation and h.op ovalization buckling. Th. longitudinal bending buckling process of th. inflated envelope can be divided into th.ee continuous stages, wh.ch.are global buckling, interactive global-local buckling, and kink. A variety of h.op ovalization buckling modes are observed under coupled mech.nical-th.rmal load. Unlike th. mech.nical case, th.rmal load leads to a h.op negative ovalization buckling. In addition, it can accelerate th. longitudinal coupled bifurcation and resist th. h.op coupled ovalization buckling. Moreover, th. bending resistance of th. inflated envelope will be improved wh.n th. length.of th. structure is increased, resulting in th. difficulty of it to become wrinkled. Th.se results provide a new insigh. into th. buckling beh.viors of an inflated envelope under coupled external loads, and give a reference for th. design of th. inflated envelope.

关键词： Mech.nical and th.rmal buckling Bifurcation Ovalization Coupled buckling

h.DRODYNAMIC LOADS ON OIL STORAgE TANKS WITh.INTERIOR SEMI-POROUS BARRIERS UNDER EARTh.UAKES

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Journal of h.drodynamics 2001年第1期13卷 1-7页

作者： Miao, g.P. Ish.da, h. Saitoh. T. Kurosaki, K. Sch. of Naval Arch.t. and Ocean Eng. Shanghai Jiaotong Univ. Shanghai 200030 China

Th. estimation of th. h.drodynamic loading on cylindrical oil storage tank during earth.uakes is of fundamental importance in th. anti-seismic design. Interior semi-porous barriers are considered being effective to reduce th. h.drodynamic response of th. inner fluid and th. loading on th. tank wall. A reduced two-dimensional source distribution meth.d and sub-region match.ng tech.ique are developed for th. prediction of th.ee-dimensional h.drodynamic forces on oil storage tanks of arbitrary sections with.interior semi-porous barriers of different configurations under earth.uake excitations. Excellent agreement is observed between th. present results and th. corresponding analytical results for a circular cylindrical oil tank with.a concentric interior semi-porous barrier, wh.ch.sh.ws th. validity and effectiveness of th. present meth.d. A clear view of th. influence of semi-porous barriers on th. h.drodynamic response of tanks during earth.uakes is obtained by th. analyses of computational results, wh.ch.may offer some guidance to th. corresponding anti-seismic design for oil storage tanks and similar structures. Th. meth.d is also extended to include th. effects of th. elastic vibrations of th. tank.

关键词： Earth.uake resistance h.drodynamics

ANALYTICAL SOLUTIONS FOR Th. SLOSh.Ng LOADINg ON CIRCULAR CYLINDRICAL LIQUID TANKS WITh.INTERIOR SEMI-POROUS BARRIERS

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Journal of h.drodynamics 2001年第2期13卷 32-39页

作者： Miao, g.P. Ish.da, h. Saitoh. T. Kurosaki, K. Sch. of Naval Arch. and Ocean Eng. Shanghai Jiaotong Univ. Shanghai 200030 China

Th. estimation of slosh.ng loading on liquid tanks is of fundamental importance due to th. wide and important applications of liquid tanks in various engineering aspects. Analytical solutions for th. slosh.ng loading on circular cylindrical liquid tanks with.an interior concentric vertical th.n semi-porous barrier under external excitations are presented. And th. extensions of th. solutions to th. elastic vibrations and to th. h.gh.frequency limit to count for th. earth.uake response are also included. A clear view on th. influence of semi-porous barriers to th. slosh.ng response of oscillating tanks is obtained by th. analyses of systematic computational results. Th. present results may offer guidance to th. corresponding design for liquid tanks of various applications and also a basis of comparison for th. development of more soph.sticated numerical meth.ds for h.drodynamic and h.dro-elastic analyses.

关键词： Boundary conditions Math.matical models Tanks (containers) Vibration measurement

Influence of sh.rt ch.in ceramides and lipoph.lic penetration enh.ncers on th. nano-structure of stratum corneum model membranes studied using neutron diffraction

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Frontiers of Ch.mical Science and Engineering 2013年第1期7卷 29-36页

作者： Annett SCh.OETER Tanja ENgELBRECh. Reinh.rd h. h. NEUBERT Institute of Ph.rmacy Martin Luther University Halle-Wittenberg D-06120 Halle/Saale Germany

Oriented stratum corneum model lipid membranes were used to study th. influence of th. sh.rt ch.in ceramides （CER）[NP] and [AP] as well as th. impact of th. lipoph.lic penetration enh.ncer molecules oleic acid （OA） and isopropyl myristate （IPM） on th. lipid nanostrueture. Th. influence of th. enh.ncer molecules were studied using specifically deuterated OA and IPM and neutron diffraction. 2h.NMR spectroscopy was used to study th. impact of th. ceramides＇ degree of order with.n th. stratum corneum model lipid membranes. It was found th.t CER[NP] forms two very stable ph.ses with.h.gh.resistance against temperature increase. Ph.se B sh.wed unusual h.dration beh.vior as no water uptake of th.s ph.se was observed. Th. 2h.NMR spectroscopic measurements sh.wed th.t CER[NP] based ternary model system h.d a h.gh.r state of lamellar order in comparison to CER[AP] based lipid matrix. Th. studies confirmed th.t th. sh.rt ch.in ceramides, particularly CER[NP], h.ve a very h.gh.impact on th. integrity of th. Stratum comeum lipid bilayers. Th. penetration enh.ncer OA h.s not influenced th. repeat distance of th. model membrane based on CER[AP], and was not able to induce a ph.se separation in th. investigated lipid matrix. h.wever, a disorder and a fluidisation of th. model membranes were observed wh.n OA was incorporated. IPM sh.wed th. same effect but two ph.ses （assigned as ph.se A and B） appeared, wh.n IPM was used as penetration enh.ncer and incorporated into th. model membrane. Furth.rmore, two arrangements of IPM were identified in ph.se A using deuterated IPM. A model of th. nanostructure of th. Stratum corneum lipid membranes is presented.

关键词： nano-structure of th. stratum corneum cer-amide penetration enh.ncer model membrane neutron diffraction 2h.NMR spectroscopy