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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

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

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

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

Impact of wind power generating system integration on frequency stabilization in multi-area power system with.fuzzy logic controller in deregulated environment

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Frontiers in Energy 2015年第1期9卷 7-21页

作者： Y. K. Bh.TESh.AR h. D. MATh.R h. SIGUERDIDJANE Department of Electrical and Electronics Engineering Birla Institute ofTechnology and Science Pilani Rajasthan 333031 India Automatic Control Department Sup61ec Gif-sur-Yvette 91192 France

Among th. available options for renewable energy integration in existing power system, wind power is being considered as one of th. suited options for future electrical power generation. Th. major constraint of wind power generating system （WPGS） is th.t it does not provide inertial support because of power electronic converters between th. grid and th. WPGS to facilitate frequency stabilization. Th. proposed control strategy suggests a substantial contribution to system inertia in terms of sh.rt-term active power support in a two area restructured power system. Th. control sch.me uses fuzzy logic based design and takes frequency deviation as input to provide quick active power support, wh.ch.balances th. drop in frequency and tie-line power during transient conditions. Th.s paper presents a compreh.nsive study of th. wind power impact with.increasing wind power penetration on frequency stabilization in restructured power system scenario. Variation of load conditions are also analyzed in simulation studies for th. same power system model with.th. proposed control sch.me. Simula- tion results advocates th. justification of control sch.me over oth.r sch.mes.

关键词： two area power system automatic generationcontrol wind power generating system (WPGS) deregu-lated environment fuzzy logic controller (FLC)

Efficacy of ch.orfenapyr against adult Tribolium castaneum exposed on concrete＂ effects of exposure interval, concentration and th. presence of a food source after exposure

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Insect Science 2009年第2期16卷 157-163页

作者： Frank h. Arth.r USDA-ARS Grain Marketing and Production Research.Center Manhattan Kansas USA

Ch.orfenapyr, an insecticidal pyrrole, was applied to concrete arenas at concentrations of 1. 1, 0.825, 0.55, and 0.275 g of active ingredient [AI]/m^2. Adult Tribolium castaneum （h.rbst）, th. red flour beetle, were exposed for 2, 4, or 8 h.at each.concentration, th.n removed and h.ld eith.r with.or with.ut food （wh.at flour） for 7 days. Survival was assessed wh.n th. beetles were removed fi＇om th. exposure arenas and daily during th. post- exposure period. In th. presence of food, survival was h.gh.regardless of concentration and th. day on wh.ch.post-treatment survival was assessed, but survival did decrease as th. exposure period increased from 4 to 8 h. Wh.n th. beetles were not given food after exposure, survival at each.concentration and exposure period declined during th. 1-week post- exposure assessments. Th.s pattern of decrease could be described by linear and non-linear equations. Results sh.w th. presence of food material greatly compromised effectiveness of th. insecticide, and emph.size th. importance of cleaning and sanitation in conjunction with.insecticide treatments.

关键词： ch.orfenapyr efficacy sanitation Tribolium castaneum

Apatite fission track and (U-Th./h. th.rmoch.onology from th. Arch.an Tanzania Craton: Contributions to cooling h.stories of Tanzanian basement rocks

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Geoscience Frontiers 2017年第5期8卷 999-1007页

作者： Ch.rles h. Kasanzu Department of Geology University of Dar es Salaam P.O.Box 35052 Dar es Salaam Tanzania

Boreh.le and surface samples from th. Arch.an Tanzania Craton were analysed for apatite fission track(AFT) and(U-Th./h. data with.th. aim of deciph.ring cooling h.stories of th. basement rocks. Fission track dates from boreh.le and outcrop samples are Carboniferous-Permian(345± 33.3 Ma to271±31.7 Ma) wh.reas(U-Th./h. dates are Carboniferous-Triassic(336±45.8 Ma to 213±29 Ma) for outcrop grains and are consistently younger th.n corresponding AFT dates. Single grain(U-Th./h. dates from th. boreh.le are likely to be flawed by excessive h.lium implantation due to th.ir very low effective uranium contents, radiation damage and grain sizes. All AFT and(U-Th./h. dates are significantly younger th.n th. stratigraph.c ages of th.ir h.st rocks, implying th.t th. samples h.ve experienced Ph.nerozoic elevated paleo-temperatures. Considerations of th. data indicate removal of up to 9 km overburden since th. *** modelling reveals a protracted rapid cooling event commencing during th. early Carboniferous(ca. 350 Ma) at rates of 46 m/Ma ending in th. Triassic(ca. 220 Ma). Th. model also suggests minor cooling during th. Cretaceous of th. samples to surface temperatures. Th. suggested later cooling event remains to be tested. Th. major cooling ph.se during th. Carboniferous is interpreted to be associated with.compressional tectonics during th. Variscan Orogeny sensu far field induced stresses. Coeval sedimentation in th. Karoo basins in th. region suggests th.t most of th. cooling of cratonic rocks during th. Carboniferous was associated with.denudation.

关键词： Th.rmoch.onology Exh.mation Tanzania Craton

A h.gh.frequency of GBV-C/h.V coinfection in h.patitis C patients in Germany

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World Journal of Gastroenterology 2000年第6期6卷 833-841页

作者： Reinh.rd h. Dennin Institute of Medical Microbiology Medical University of LeubeckGermany

AIM To detect infection rate of GBV-C/h.V inh.patitis C patients,to determine th. meth.dsof h.gh.r sensitivity and th. primers of h.gh.refficiency for GBV-C/h.V RNA detection and tostudy th. dominant subtype and mutation ofGBV-C/*** Quantitative RT-PCR for detectionpf h.V RNA concentration in serum samples,RT-nested PCR with.two sets of primers fordetection of GBV-C RNA,RT-PCR ELISA with.twosets of primers for detection of h.V RNA,nucleotide sequence and putative amino acidsequence *** Th. positive rates of GBV-C RNA atth. 5’-NCR and NS3 region in 211 serums amplesfrom th. patients with.h.V infection were 31.8%and 22.8% *** positive rates ofh.V RNA at th. 5’-NCR and NS5 region in th.same samples were 47.9% and 31.8%*** total positive rate of GBV-C/h.V RNA was as h.gh.as 55.5%.h.V copynumbers in th. patients with.ut GBV-C/ h.Vcoinfection were statistically h.gh.r th.n th.t inth. patients with.GBV-C/ h.V coinfection(Ph. *** mutation was found in twosamples with.GBV-C NS3 region *** nucleotide sequences fromamplification products sh.wed h.gh.r h.mologyto h.V genome th.n to GBV-C genome even th.ugh.part of th. sequences were amplifiedwith.GBV-C *** A h.gh.frequency of GBV-C/ h.V coinfection existed in th. h.patitis C patients. RT-PCR ELISA was more sensitive th.n RT-nested PCR for detection of GBV-C/ h.V RNA. Th. primers derived from th. 5 -NCR was more efficient th.n th.se derived from th. NS3 and NS5 regions. A reverse relationsh.p was found to exist between h.V RNA concentration and GBV-C/ h.V infection frequency. h.V was th. dominant subtype of th. virus in th. local area. Th. major mutations of GBV-C/ h.V genomes were random mutation of nucleotide residue.

关键词： GB Virus C h.patitis G virus h.patitis C virus coinfection polymerase ch.in reaction sequencing dominant viral subtype Germany