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71.
Seung H. Son 《Journal of Number Theory》2006,121(1):114-117
Ramanujan recorded additive formulae of theta functions that are related to modular equations of degree five. We present elementary and simple proofs. 相似文献
72.
S.I. Jung J.J. Yoon H.J. Park Y.M. Park M.H. Jeon J.Y. Leem C.M. Lee E.T. Cho J.I. Lee J.S. Kim J.S. Son J.S. Kim D.Y. Lee I.K. Han 《Physica E: Low-dimensional Systems and Nanostructures》2005,26(1-4):100
We investigate the effects of a thin AlAs layer with different position and thickness on the optical properties of InAs quantum dots (QDs) by using transmission electron microscopy and photoluminescence (PL). The energy level shift of InAs QD samples is observed by introducing the thin AlAs layer without any significant loss of the QD qualities. The emission peak from InAs QDs directly grown on the 4 monolayer (ML) AlAs layer is blueshifted from that of reference sample by 219 meV with a little increase in FWHM from 42–47 meV for ground state. In contrast, InAs QDs grown under the 4 ML AlAs layer have PL peak a little redshifted to lower energy by 17 meV. This result is related to the interdiffusion of Al atom at the InAs QDs caused by the annealing effect during growing of InAs QDs on AlAs layer. 相似文献
73.
D. N. Son N. ArboledaJr W. A. Dino H. Kasai 《The European Physical Journal B - Condensed Matter and Complex Systems》2007,57(1):27-35
We consider a two-terminal Aharonov-Bohm (AB) interferometer with a quantum dot inserted in one path of the AB ring.
We investigate the transport properties of this system in and out of the Kondo regime. We utilize perturbation theory to
calculate the electron self-energy of the quantum dot with respect to the intradot Coulomb interaction. We show the expression
of the Kondo temperature as a function of the AB phase together with its dependence on other characteristics such as the
linewidth of the ring and the finite Coulomb interaction and the energy levels of the quantum dot. The current oscillates
periodically as a function
of the AB phase. The amplitude of the current oscillation decreases with increasing Coulomb interaction. For a given temperature,
the electron transport through the AB interferometer
can be selected to be in or out of the Kondo regime by changing the magnetic flux threading perpendicular to the AB ring of
the system. 相似文献
74.
The effect of entrainment and the role of the interface during the interaction between an axisymmetric turbulent mass plume
and a strong stratified layer are investigated. We describe mainly the characteristics of the plume: the change in the profiles
of the density, the horizontal component of the velocity and the corresponding intensity of turbulence, the change in the
entrainment co-efficient, when the plume goes through the impingement interface, assuming a self-similar Gaussian property
of the axial velocity component and of the density difference. The influence of the stratification on the plume angle coefficient
is studied, and compared with the results related to a homogeneous environment, obtained elsewhere. Experimental correlation
on the mean entrainment coefficient in a given plume cross-section, is formulated. 相似文献
75.
A closed system of equations for the second moments, determining the turbulent transfer in inhomogeneous flows with body forces, is obtained in the local equilibrium approximation. Taking diffusion and convective transfer into account does not present difficulties, since the expressions obtained for the terms containing the fluctuations of the body forces and transfer terms are preserved. The effect of the external forces is considered for two cases: turbulent motion in a stratified medium and conducting flows in a longitudinal magnetic field. In the latter case the external forces are divergenceless and they therefore do not affect the pressure fluctuations. A single-scale model, in which the transverse scale is taken as the scale in the boundary layer, is considered.Translated from Izvestiya Akademii Nauk SSSS, Mekhanika Zhidkosti i Gaza, No. 3, pp. 33–40, May–June, 1985. 相似文献
76.
Phosphorescent Ruthenium Complexes with a Nitroimidazole Unit that Image Oxygen Fluctuation in Tumor Tissue 下载免费PDF全文
Dr. Aoi Son Atsushi Kawasaki Daiki Hara Dr. Takeo Ito Dr. Kazuhito Tanabe 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(6):2527-2536
Understanding oxygen fluctuation in a cancerous tumor is important for effective treatment, especially during radiotherapy. In this paper, ruthenium complexes bearing a nitroimidazole group are shown to report the oxygen status in tumor tissue directly. The nitroimidazole group was known to be accumulated in hypoxic tumor tissues. On the other hand, the ruthenium complex showed strong phosphorescence around 600 nm. The emission of ruthenium is quenched instantaneously by molecular oxygen due to energy transfer between triplet states of oxygen and ruthenium complex, but the emission is then recovered by the removal of oxygen. Thus, we could observe oxygen fluctuation in tumor tissue in a real‐time manner by monitoring the phosphorescence of the ruthenium complex. The versatility of the probe is demonstrated by monitoring oxygen fluctuation in living cells and tumor tissue planted in mice. The ruthenium complex promptly penetrated plasma membrane and accumulated in cells to emit its oxygen‐dependent phosphorescence. In vivo experiments revealed that the oxygen level in tumor tissue seems to fluctuate at the sub‐minute timescale. 相似文献
77.
Gobinda Gyawali Jieun Son Nguyen Huy Hao Sung Hun Cho Tae-Ho Kim Soo Wohn Lee 《Research on Chemical Intermediates》2017,43(9):5055-5065
TiO2 nanotubes (TNTs) were successfully synthesized from different alkaline media (i.e., NaOH and KOH) by using a microwave hydrothermal process. The effects of different alkaline media on the formation of TiO2 nanotubes and their physicochemical properties were investigated. The phases of different TiO2 nanostructures were studied by using X-ray diffraction patterns. Morphologies of the nanostructures were observed with a transmission electron microscope. The optical properties of the nanostructures were evaluated through the absorption behavior using UV–Vis diffuse reflectance spectroscopy. The photocatalytic activities of the TiO2 nanostructures were evaluated by the degradation of methylene blue aqueous dye solution under the simulated solar light irradiation. Similarly, the photovoltaic efficiencies of the prepared samples were investigated by making photo-anode layers in the Dye Sensitized Solar Cells (DSSCs). The results revealed that in comparison to the single layered TiO2 nanostructures in the DSSC, creation of a double layer structure significantly enhanced the efficiency of DSSC. 相似文献
78.
Le Hoang Son 《Fuzzy Optimization and Decision Making》2017,16(3):359-378
In this paper, we extend the basic distance measure in picture fuzzy sets to the new measures called generalized picture distance measures and picture association measures. Some properties of these measures are examined. An application to clustering problem is given to illustrate applicability of the proposed works. 相似文献
79.
Quoc Son Nguyen 《Comptes Rendus Mecanique》2003,331(1):99-112
A review on the stability analysis of solids in unilateral and frictional contact is given. The presentation is focussed on the stability of an equilibrium position of an elastic solid in frictional contact with a fixed or moving obstacle. The problem of divergence instability and the obtention of a criterion of static stability are discussed first for the case of a fixed obstacle. The possibility of flutter instability is then considered for a steady sliding equilibrium with a moving obstacle. The steady sliding solution is generically unstable by flutter and leads to a dynamic response which can be chaotic or periodic. This dynamic response leads to the generation of stick–slip–separation waves on the contact surface in a similar way as Schallamach waves in statics. Illustrating examples and principal results recently obtained in the literature are reported. Some problems of friction-induced vibration and noise emittence, such as brake squeal for example, can be interpreted in this spirit. To cite this article: Q.S. Nguyen, C. R. Mecanique 331 (2003). 相似文献
80.
Diffusion of chemical elements into an ionized multicomponent gaseous mixture is considered in a model of local thermodynamic equilibrium. A linear dependence of the mass flows of chemical elements and the heat flow on the temperature gradient, mass fractions of the chemical elements, and the electric field is obtained. An example is given of a calculation of the effective diffusion coefficients for a hydrogen-helium mixture. 相似文献