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891.
Nonlinear Dynamics - In this article, we present a system of coupled short pulse equations as integrability condition of associated generalized linear eigenvalue problem. We obtain system of... 相似文献
892.
Radiophysics and Quantum Electronics - We study the emergence of steady wave packets in the form of envelope solitary waves (envelope solitons) which evolve from localized pulse-type initial... 相似文献
893.
At DIII-D, a slot divertor concept, called small-angle-slot (SAS), is under development, aiming to enable detachment at relatively low plasma edge density. We report on simulations using the SOLPS-ITER two-dimensional edge code to examine the performance of conceptual “SAS 2” slot configurations. The focus of the analysis is on E × B drift effects on upstream density at detachment (UDD), with detachment marked by electron temperature Te ≤ 3 eV at the outer strike point (OSP). With toroidal field such that radial E × B drift carries particles from the OSP towards the private flux region (PFR), placing the OSP near the inner slot wall gives ≈20% lower UDD than having the OSP near the outer wall. The inner wall effectively traps the radial E × B drift flux, resulting in low Te and associated radial electric field in the PFR, and thus small losses from the slot to the inner target via poloidal E × B drift flux. With toroidal field reversed such that radial E × B drift is reversed, OSP placement near the inner wall gives ≈10% lower UDD than OSP placement near the outer wall. Although radial E × B flux is from the OSP towards the outer wall, this flux largely escapes the slot, raising the UDD. A change in the slot shaping is suggested with the goal of eliminating such E × B -driven particle losses from the slot. 相似文献
894.
Artem Yakovliev Tymish Y. Ohulchanskyy Roman Ziniuk Tereza Dias Xin Wang Hao Xu Guanying Chen Junle Qu Anderson S. L. Gomes 《Particle & Particle Systems Characterization》2020,37(2):1900445
In this work, the application of near infrared (NIR)-emitting NaYbF4:1%Tm3+@NaLuF4:30%Nd3+ core–shell nanoparticles is reported for noninvasive probing and monitoring the temperature during photopolymerization of dental materials. When excited at 808 nm, the synthesized nanoparticles emit NIR photoluminescence (PL) with two distinctive peaks at 865 and 980 nm which correspond to radiative transitions from the doped Nd3+ and Yb3+ ions, respectively. Luminescence intensity ratio between these two bands is found to vary with temperature due to temperature-dependent electronic excitation energy transfer between Nd3+ and Yb3+ ions at the core/shell interface. This finding allows luminescence ratiometric evaluation of the in situ temperature during photopolymerization of resin cement (doped with nanoparticles) in a veneer placement procedure. In addition, the NIR emission also enables PL imaging of the distribution of the adhesive under the veneer. The results highlight that rare-earth ions–doped nanoparticles with both excitation and emission in the NIR spectral range are advantageous for both PL-based nanothermometry and imaging due to the reduced attenuation of NIR light by dental ceramics. 相似文献
895.
Pham Y. Yu Y. K. Manh T. V. Gamzatov A. Tartakovsky D. M. Yu S.-C. Yang D.-S. Kim D.-H. 《Physics of the Solid State》2020,62(5):845-850
Physics of the Solid State - Structural and magnetic properties of Sr-doped Pr0.7Ba0.3MnO3 polycrystallines prepared by solid state reaction are presented. Samples were in monoclinic structure... 相似文献
896.
Russian Physics Journal - A new mathematical model of oscillations of mesh micropolar geometrically nonlinear cylindrical panels under the action of a normal alternating distributed load has been... 相似文献
897.
N. S. Takahashi Y. Hunyu E. Shibano N. Mochizuki S. Kurita 《Crystal Research and Technology》1993,28(5):711-716
The fabrication and characterization of double-heterostructure (DH) laser that utilizes an indium-tin oxide (Ito) transparent cladding and top contact layer. The first room-temperature lasing operation has been obtained form ITO/InGaAsP/AlGaAs DH laser diode at threshold current density of 12.1 kA/cm2. The interfacial recombination velocity of ITO/InGaAsP Interface was estimated to be 4.9 × 104 cm/s from a simple model to account for high threshold current, and optical measurements of spontaneous emission and lasing spectra from top stripe window and facet were done. 相似文献
898.
Y. S. Wang P. Bennema M. N. Zheng C. M. Fu P. van der Linden 《Crystal Research and Technology》1993,28(7):1015-1020
A mechanism of high-Tc superconductivity related to the perovskite crystal structure is proposed by a “phonon attenuation model”, which means that in the perovskite-like crystal structure, a number of “ordering” vacancies or holes occur due to the non-stoichiometric structure features. Such a reticular “spongly-like” structure facilitates lattice thermovibration attenuation perovskite (phonon attenuation) during temperature reduction. This leads to an abrupt drop of the resistivity, owing to the conduction electrons transmitted through the media without collision with irregularities in the lattice due to the lattice thermovibration. This probably is the main reason for high-Tc superconductivity of the perovskite cuprates. 相似文献
899.
900.
Guo J. Dadashi S. Bender M. Paruchuri S. T. Powell N. Sharma Y. Kurdila H. McGlothlin J. W. Kurdila A. J. 《Nonlinear dynamics》2019,98(1):195-213
Nonlinear Dynamics - In contrast to many systems studied in the field of classical mechanics, models of animal motion are often distinguished in that they are both highly uncertain and evolve in a... 相似文献