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Towards an understanding of.Type Ia supernovae f.om.a synthesis of.theory and observations

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f.ontiers of.physics 2013年第2期8卷 116-143页

作者： W. Hillebrandt m. Krom.r f. K. Ropke A. J. Ruiter m.x-Planck-Institut f.ir Astrophysik Karl-Schwarzschild-Str. 1 D-85741 Garching Germany Institut f.ir Theoretische Physik und Astrophysik Universit~it Wiirzburg Am Hubland D-97074 Wiirzburg Germany

m.tivated by the f.ct that calibrated light curves of.Type Ia supernovae （SNe Ia） have becom. a m.jor tool to determ.ne the expansion history of.the Universe, considerable attention has been given to, both, observations and m.dels of.these events over the past 15 years. Here, we sum.arize new observational constraints, address recent progress in m.deling Type Ia supernovae by m.ans of.three-dim.nsional hydrodynam.c sim.lations, and discuss several of.the still open questions. It will be be shown that the new m.dels have considerable predictive power which allows us to study observable properties such as light curves and spectra without adjustable non-physical param.ters. This is a necessary requisite to im.rove our understanding of.the explosion m.chanism.and to settle the question of.the applicability of.SNe Ia as distance indicators f.r cosm.logy. We explore the capabilities of.the m.dels by com.aring them.be applied to study the origin of.the diversity with observations and we show how such m.dels can of.SNe Ia.

关键词： supernovae nucleosynthesis stellar evolution binary and m.ltiple stars nuclearreactions

Application of.RNA interf.rence in triatom.ne （Hem.ptera： Reduviidae） studies

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Insect Science 2013年第1期20卷 40-52页

作者： Raf.ela m. m. Paim.Ricardo N. Araujo m.chael J. Lehane Nelder f. Gontijo m.rcosH. Pereira Departam.nto de Parasitologia Instituto de Ciencias Biologicas Universidade Federal de Minas Gerais Bloco 14 Sala 177 Av. AntonioCarlos 6627 Pampulha CEP 30270-901 Belo Horizonte MG Brazil Liverpool School of.Tropical m.dicine Pembroke Place LiverpoolL3 5QA UK

Triatom.nes （Hem.ptera： Reduviidae） are obligate hem.tophagous insects. They are of.m.dical im.ortance because they are vectors of.Trypanosom. cruzi, the causative agent of.Chagas disease in the Am.ricas. In recent years, the RNA interf.rence （RNAi） technology has em.rged as a practical and usef.l alternative m.ans of.studying gene f.nction in insects, including triatom.ne bugs. RNAi research in triatom.nes is still in its early stages, several issues still need to be elucidated, including the description of.the m.lecules involved in the RNAi m.chinery and aspects related to phenotype evaluation and persistence of.the knockdown in dif.erent tissues and organs. This review considers recent applications of.RNAi to triatom.ne research, describing the m.jor m.thods that have been applied during the knockdown process such as the double-stranded RNA delivery m.chanism.（injection, m.croinjection, or ingestion） and the phenotype characterization （m.NA and target protein levels） in studies conducted with the intent to provide greater insights into the biology of.these insects. In addition to the characterization of.insect biom.lecules, som. with biopharm.cological potential, RNAi m.y provide a new view of.the interaction between triatom.ne and trypanosom.tids, enabling the developm.nt of.new m.asures f.r vector control and transm.ssion of.the parasite.

关键词： dsRNA knockdown phenotype RNAi triatom.ne

Ef.icient Visible Photolum.nescence f.om.Self.Assem.led Ge QDs Em.edded in Silica m.trix

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Chinese Physics Letters 2017年第6期34卷 112-116页

作者： Alireza Sam.vati Zahra Sam.vati A. f. Ism.il m. H. D. Othm.n m. A. Rahm.n A. K. Zulhairun Advanced m.m.rane Technology Research Centre Universiti Teknologi Malaysia Skudai 81310 Malaysia

m.asuring the growth param.ters of.Ge quantum.dots （QDs） em.edded in SiO2/Si hetero-structure is pre- requisite f.r developing the optoelectronic devices such as photovoltaics and sensors. Their optical properties can be tuned by tailoring the growth m.rphology and structures, where the growth param.ters＇ optim.zations still need to be explored. We determ.ne the ef.ect of.annealing tem.erature on surf.ce m.rphology, structures and optical properties of.Ge//SiO2//Si hetero-structure. Sam.les are grown via rf.m.gnetron sputtering and subsequent characterizations are m.de using im.ging and spectroscopic techniques.

关键词： Ge Ef.icient Visible Photolum.nescence f.om.Self.Assem.led Ge QDs Em.edded in Silica m.trix QDs

Current State of.High 120 m.Concrete Dam.Bratsk Hydroelectric Power Plant

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Journal of.Civil Engineering and Architecture 2017年第3期11卷 222-231页

作者： m.rk A. Sadovich Tatyana f. Shlyakhtina Sof.a m. Ginzburg Alexander m. Yudelevich Departm.nt of.Civil Engineering Bratsk State University Bratsk 665709 Russia Departm.nt of.Concrete and Reinf.rced Concrete Structure Vedeneev VNIIG St.Petersburg 195220 Russia

The research object was high 120 m.concrete gravity dam.of.the Angara Bratsk hydroelectric power plant. The state of.the concrete dam.is estim.ted based on the results of.continuous supervision perf.rm.d by site personnel as well as periodic m.nitoring. According to the classif.cation of.the interrelations in the system.＂concrete-environm.nt＂, there were selected som. im.ortant parts of.dam. and a com.rehensive analysis of.concrete was executed on these parts. Concerning the com.lex research of.concrete, a com.ination of.f.ll-scale tests with core-sam.ling has been proposed. Core sam.les tests had an object to study the deep concrete layers and to determ.ne the specif.c indicators such as strength, density, porosity, com.arative diam.ter of.capillary pores, CaO content in cem.nt stone and others. Obtained f.ndings and recom.ended criteria can be applied when selecting technologies f.r constructing dam. that guarantee their durability in the north.

关键词： Concrete gravity dam hydroelectric power plant m.nitoring.

OPTIm.ZATION Of.THE SYNTHESIS Of.ACRYLAm.DE HYDROGEL BY γ-RAY IRRADIATION

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Chinese Journal of.Polym.r Science 2004年第3期22卷 253-258页

作者： m.A. Chowdhury m.m. Alam.m.f. m.na f. Akhtar S.E. Kabir Departm.nt of.Chem.stry Faculty of Science Jahangir Nagar University Dhaka BangladeshNRCD INST AERE GPO Box-3787 Dhaka Bangladesh NRCD INST AERE GPO Box-3787 Dhaka Bangladesh NRCD INST AERE GPO Box-3787 Dhaka Bangladesh Department of Chemistry Faculty of Science Jahangir Nagar University Dhaka Bangladesh

Hydrogels have been synthesized f.om.10%, 20%, 30%, 40%, 50% and 60% aqueous solutions of.acrylam.de m.nom.r by gam.a radiation em.loying doses in the range of.0.2-30 kGy f.om.a Co-60 source. The ef.ect of.solution concentration, γ-ray dose, pH and tim. was studied in order to observe the optim.zing conditions in the characterization of.hydrogels. Gel f.action increases with dose f.r all concentrations indicating hundred-percentage conversion of.gel at doses 5 kGy f.r hom.genous solutions in the range of.20%-50% concentration. On the other hand, 10% solution provides conversion less than 86% even at 30 kGy, whereas 60% m.nom.r m.kes an inhom.geneous solution which stile gives about 100% gel f.action. Swelling of.hydrogels under water with respect to tim. varies with both the doses and concentrations due to the change of.crosslinking density in the gels. The m.xim.m.volum. change of.hydrogels during swelling and water desorption m.inly occurs within 24 h. Swelling is also enhanced with the rise of.pH due to change of.ionic content of.the solvent. Considering the am.unt of.gel f.action and the properties of.hydrogel, the sam.les prepared f.om.20% solution at 5 kGy show better results. m.reover, the ef.ect of.bacteria on hydrogel was f.und to be nil, suggesting a prohibition of.growth of.m.croorganism.in it.

关键词： Hydrogel Acrylam.de γ-radiation Swelling m.croorganism

Electro-Hydrodynam.cs and Kinetic m.deling of.Dry and Hum.d Air f.ows Activated by Corona Discharges

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Plasm. Science and Technology 2016年第5期18卷 469-472页

作者： J. P. SARRETTE O. EICHWALD f. m.RCHAL O. DUCASSE m. YOUSf. CNRS LAPLACE Toulouse F-31062 France Universite de Toulouse UPS INPTLAPLXCE (Laboratoire Plasma et Conversion d'Energie) Toulouse Cedex 9 F-31062 France

The present work is devoted to the 2D sim.lation of.a point-to-plane Atm.spheric Corona Discharge Reactor （ACDR） powered by a DC high voltage supply. The corona reactor is periodically crossed by thin m.no f.lam.ntary stream.rs with a natural repetition f.equency of.som. tens of.kHz. The study com.ares the results obtained in dry air and in air m.xed with a sm.ll am.unt of.water vapour （hum.d air）. The sim.lation involves the electro-dynam.cs~ chem.cal kinetics and neutral gas hydrodynam.cs phenom.na that inf.uence the kinetics of.the chem.cal species transf.rm.tion. Each discharge lasts about one hundred of.a nanosecond while the post- discharge occurring between two successive discharges lasts one hundred of.a m.crosecond. The ACDR is crossed by a lateral dry or hum.d air f.ow initially polluted with 400 ppm.of.NO. Af.er 5 m., the tim. corresponding to the occurrence of.50 successive discharge/post-discharge phases, a higher NO rem.val rate and a lower ozone production rate are f.und in hum.d air. This change is due to the presence of.the HO2 species f.rm.d f.om.the H prim.ry radical in the discharge zone.

关键词： DC corona discharge hum.d air chem.stry plasm. sim.lation NO treatm.nt

Nonlinear three-dim.nsional stretched f.ow of.an Oldroyd-B f.uid with convective condition, therm.l radiation, and m.xed convection

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Applied m.them.tics and m.chanics(English Edition) 2017年第7期38卷 969-980页

作者： B. m.HANTHESH B. J. GIREESHA S.A. SHEHZAD f.m. abbasi R. S. R. GORLA Departm.nt of.m.them.tics Christ University Bangalore 560029 Karnataka India Departm.nt of.Studies and Research in m.them.tics Kuvempu University Shankarghatta 577451 Karnataka India Departm.nt of.m.them.tics COMSATS Institute of Information Technology Sahiwal 57000 Pakistan Departm.nt of.m.them.tics COMSATS Institute of Information Technology Islamabad 44000 Pakistan Departm.nt of.m.chanical and Civil Engineering Purdue University Northwest Indiana 46391 U. S. A

The ef.ect of.non-linear convection in a lam.nar three-dim.nsional Oldroyd-B f.uid f.ow is addressed. The heat transf.r phenom.non is explored by considering the non-linear therm.l radiation and heat generation/absorption. The boundary layer as- sum.tions are taken into account to govern the m.them.tical m.del of.the f.ow analy- sis. Som. suitable sim.larity variables are introduced to transf.rm.the partial dif.eren- tial equations into ordinary dif.erential system.. f.f.h-order techniques with the shooting m.thod The Runge-Kutta-f.hlberg f.urth- and are used to obtain the solutions of.the dim.nsionless velocities and tem.erature. The ef.ects of.various physical param.ters on the f.uid velocities and tem.erature are plotted and exam.ned. A com.arison with the exact and hom.topy perturbation solutions is m.de f.r the viscous f.uid case, and an excellent m.tch is noted. The num.rical values of.the wall shear stresses and the heat transf.r rate at the wall are tabulated and investigated. The enhancem.nt in the values of.the Deborah num.er shows a reverse behavior on the liquid velocities. The results show that the tem.erature and the therm.l boundary layer are reduced when the non- linear convection param.ter increases. The values of.the Nusselt num.er are higher in the non-linear radiation situation than those in the linear radiation situation.

关键词： nonlinear therm.l convection nonlinear therm.l radiation Oldroyd-B f.uid,convective boundary condition heat source/sink

Therm.l Spray Coating of.Tungsten f.r Tokam.k Device

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Plasm. Science and Technology 2006年第2期8卷 164-167页

作者：蒋显亮 f. GITZHOf.R m.I. BOULOS Institute of.Surf.ce and Coatings Technology Central South University Changsha 410083 China Plasm. Technology Research Center University of Sherbrooke Sherbrooke J1K 2R1Canada

Therm.l spray, such as direct current （d.c.） plasm. spray or radio f.equency induced plasm. spray, was used to deposit tungsten coatings on the copper electrodes of.a tokam.k device. The tungsten coating on the outer surf.ce of.one copper electrode was f.rm.d directly through d.c. plasm. spraying of.f.ne tungsten powder. The tungsten coating/lining on the inner surf.ce of.another copper electrode could be f.rm.d indirectly through induced plasm. spraying of.coarse tungsten powder. Scanning electron m.croscopy （SEm. was used to exam.ne the cross section and the interf.ce of.the tungsten coating. Energy Dispersive Analysis of.X-ray （EDAX） was used to analyze the m.tallic elem.nts attached to a separated interf.ce. The inf.uence of.the particle size of.the tungsten powder on the density, cracking behavior and adhesion of.the coating is discussed. It is f.und that the coarse tungsten powder with the particle size of.45-75μm.can be m.lted and the coating can be f.rm.d only by using induced plasm.. The coating deposited f.om.the coarse powder has m.ch higher cohesive strength, adhesive strength and crack resistance than the coating m.de f.om.the f.ne powder with a particle size of.5μm.

关键词： tokam.k device copper electrode therm.l spray tungsten coating tungsten/copper interf.ce

A rigorous proof.of.m.m. channel capacity's increase with antenna num.er

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Optoelectronics Letters 2008年第4期4卷 280-282页

作者： GONG Jian-m.n m. R. Soleym.ni J. f. Hayes College of.Inf.rm.tion Science and Technology Jinan University Guangzhou 510632 China Departm.nt of.Electrical and Com.uter Engineering Concordia University Montreal Quebec H3G 1M8 Canada

It is well known that adding m.re antennas at the transm.tter or at the receiver m.y of.er larger channel capacity in the m.ltiple-input m.ltiple-output(m.m.) com.unication *** this letter,a sim.le proof.is presented f.r the f.ct that the channel capacity increases with an increase in the num.er of.receiving *** proof.is based on the f.m.us capacity f.rm.la of.f.schini and Gans with m.trix theory.

关键词： Antennas Com.unication system. m.trix algebra m.m.devices m.ltiplexing Receiving antennas