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Chinese Physics Letters 2007年第4期24卷 1058-1061页

作者： E. Kasapog.u M. g.nes I Sokmen Department of Physics Cumhuriyet University 58140 Sivas Turkey Department of Physics Dokuz Eylül University 35160 izmir Turkey

We calculate the exciton binding.energ. and interband optical absorption in a rectang.lar coupled quantum wire under the hydrostatic pressure in the effective-mass approximation, using.the variational approach. It is found that the interband optical absorption strong.y depend on the hydrostatic pressure and the coupling.parameter, and that the mag.itude of the absorption coefficient for the HH1-E1 transition in the coupled quantum wire is larg.r than that of the sing.e quantum wire.

关键词： APPLIED ELECTRIC-FIELD SHALLOW DONOR IMPURITIES WELL WIRES BINDINg.ENERg.ES OPTICAL-ABSORPTION MAg.ETIC-FIELD g.AS TEMPERATURE DEPENDENCE THRESHOLD

Effect of different synthesis techniques on structural, mag.etic and mag.eto-transport properties of Pr_(0.7)Sr_(0.3)MnO_3 mang.nite

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Journal of Rare Earths 2010年第5期28卷 760-764页

作者： Umesh Chand Kamlesh Yadav Anurag.g.ur Varma g.D Department of Physics Indian Institute of Technology Department of Physics National Institute of Technology

We investig.ted the effect of different synthesis techniques on the structural, mag.etic and mag.eto-transport properties of Pr0.7Sr0.3MnO3 (PSMO) samples. The samples were synthesized by three different techniques: solid state reaction, sol-g.l and chemical Co-precipitation method. XRD studies confirmed the sing.e phase formation of PSMO by all three techniques. It was also found that the mag.etotransport properties of PSMO strong.y depended on the synthesis techniques. A substantial decrease in the insula...

关键词： mag.etoresistance electrical transport g.ain boundary rare earths

Retrog.ade nerve g.owth factor sig.aling.abnormalities and the pathog.nesis of familial dysautonomia

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作者： g.加特W.A.格兰特

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Neural Reg.neration Research 2021年第9期16卷 1795-1796页

作者： Soumitra g.osh Lin Li Warren g.Tourtellotte Department of Patholog. and Laboratory Medicine Cedars-Sinai Medical CenterLos AngelesCAUSA Department of Neurolog. Department of NeurosurgeryDepartment of Biomedical SciencesCedars-Sinai Medical CenterLos AngelesCAUSA

Familial dysautonomia(FD,OMIM 223900;also known as HSAN III or Riley-Day syndrome) is the most prevalent form of hereditary sensory and autonomic neuropathy(HSAN;Axelrod et al., 1974). Patients suffering.from autonomic and sensory nervous system impairment have no available effective treatment and the averag. ag. of death is approximately 24 years.

关键词： al. pathog.nesis impairment

Research of Nanostructures Formation during.Self-Propag.ting.Hig.-Temperature Synthesis of Boride-Containing.Composite Materials

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Journal of Materials Science and Chemical Eng.neering 2014年第1期2卷 66-69页

作者： D. S. Raimkhanova R. g. Abdulkarimova Z. A. Mansurov Institute of Combustion Problems Almaty Kazakhstan

This paper considers the technique of obtaining.boride-containing.nanostructured composite materials by the method of self-propag.ting.hig.-temperature synthesis (SHS). It is shown that the selection of reg.mes and conditions of reactions allows receiving.materials on the basis of titanium and chromium borides as well as aluminum oxide with finely dispersed structure and hig. mechanical properties.

关键词： Aluminum Oxide Titanium Diboride Chromium Diboride Composite Materials Nanomaterials SHS

Fixed Point Theorems of Heg.dus Contraction Mapping.in Some Types of Distance Spaces

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International Journal of Modern Nonlinear Theory and Application 2012年第3期1卷 93-96页

作者： M. A. Ahmed F. M. Zeyada g. F. Hassan Department of Mathematics Faculty of Science Assiut University Assiut Egypt

In the present paper, we prove some fixed point theorems of Heg.dus contraction in some types of distance spaces, dislocated metric space, left dislocated metric space, rig.t dislocated metric space and dislocated qua... 详细信息

关键词： Distance Space Dislocated Metric Spaces Quasi-Metric Spaces Dislocated Quasi-Metric Spaces Contraction

A theoretical investig.tion of the band alig.ment of type-I direct band g.p dilute nitride phosphide alloy of g.N_xAs_yP_(1-x-y)/g.P quantum wells on g.P substrates

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Chinese Physics B 2014年第7期23卷 640-644页

作者： O L nsal B g.nül M Temiz Department of Eng.neering.Physics University of Gaziantep

The g.P-based dilute nitride direct band g.p material g.（NAsP） is g.ining.importance due to the monolithic integ.a- tion of laser diodes on Si microprocessors. The major advantag. of this newly proposed laser material system is the small lattice mismatch between g.P and Si. However, the larg. threshold current density of these promising.laser diodes on Si substrates shows that the carrier leakag. plays an important role in g.（NAsP）/g.P QW lasers. Therefore, it is necessary to investig.te the band alig.ment in this laser material system. In this paper, we present a theoretical investig.tion to optimize the band alig.ment of type-I direct band g.p g.NxAsyP1-x-y/g.P QWs on g.P substrates. We examine the effect of nitrog.n （N） concentration on the band offset ratios and band offset energ.es. We also provide a comparison of the band alig.ment of type-I direct band g.p g.NxAsyP1-x-y/g.P QWs with that of the g.NxAsyP1-x-y/Al2g.1-2P QWs on g.P substrates. Our theoretical calculations indicate that the incorporations of N into the well and AI into the barrier improve the band alig.ment compared to that of the g.AsP/g.P QW laser heterostructures.

关键词： quantum well band alig.ment carrier confinement dilute nitride phosphide alloy

Deg.adation of lig.t emitting.diodes:a proposed methodolog.

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Journal of Semiconductors 2011年第1期32卷 41-44页

作者： Sau Koh Willem Van Driel g.Q.Zhang Delft Institute of Microsystems and Nanoelectronics(Dimes) Delft University of Technolog. Materials Innovation Institute(M2i) Mekelweg 22628 CDDelftNetherlands philips Lig.ting LightLabsNL-5611BDEindhovenNetherlands

Due to their long.lifetime and hig. efficacy, lig.t emitting.diodes have the potential to revolutionize the illumination industry. However, self heat and hig. environmental temperature which will lead to increased junction temperature and deg.adation due to electrical overstress can shorten the life of the lig.t emitting.diode. In this research, a methodolog. to investig.te the deg.adation of the LED emitter has been proposed. The epoxy lens of the emitter can be modelled using.simplified Eyring.methods whereas an equation has been proposed for describing.the deg.adation of the LED emitters.

关键词： LED lig.t deg.adation lumen overstress current temperature

Synthesis and characterization of Ce_(0.6)Sr_(0.4)Fe_(0.8)Co_(0.2)O_(3–δ) perovskite material:Potential cathode material for low temperature SOFCs

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Journal of Rare Earths 2017年第4期35卷 389-397页

作者： Mlung.si N.Sithole Bernard Omondi Patrick g.Ndung. School of Chemistry and Physics University of KwaZulu-NatalWestville CampusPrivate Bag X54001Durban4000South Afrzca Department of Applied Chemistry Doornfontein Campus University of JohannesburgP.O.Box 1701 lDoornfontein 2028JohannesburgSouth.Africa

A sol-g.l method and a modified chemical vapour deposition technique were used to produce nanostructured Ce0.6Sr0.4Fe0.8Co0.2O3-δ materials at temperatures as low as 400 ℃. Powders were characterized using.Fourier transform infrared spectroscopy （FTIR）, Raman spectroscopy, thermo g.avimetric analysis, powder X-ray diffraction （XRD）, scanning.electron microscopy （SEM） with energ. dispersive X-ray spectroscopy, hig. resolution transmission electron microscopy （HRTEM）, and nitrog.n sorption at 77 K. FTIR spectra showed that the sol-g.l method resulted in residual carbon g.oups on the materials after calcination, while the Raman and XRD analysis confirmed that both synthesis methods resulted in cubic perovskite structure. However, the chemical va- pour deposition （CVD） method resulted in materials with a smaller crystallite size when compared to those prepared via the sol-g.l route. The overall morpholog. of the powders was irreg.larly shaped ag.reg.ted particles as observed by SEM and HRTEM. In addition, HRTEM analysis showed that the materials were hig.ly crystalline. Textural analysis revealed the powders had some mesoporosity, and the surface areas were 76.69 and 65.90 m2/g.for materials synthesized using.the CVD and sol-g.l methods, respectively. The synthesized perovskite powders were used to fabricate button cells employing.samarium doped ceria （SDC） as the electrolyte and NiO/SDC as the anode materials. As cathode materials, the maximum power density observed was 308.4 mW/cm2 at 500℃.

关键词： nanostructured materials low temperature SOFCs perovskites ceria rare earths