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排序方式: 共有9073条查询结果,搜索用时 15 毫秒
971.
Sang Chil Lee Jeong Woo Kang Hyung Soo Ahn Min Yang Nam Lyong Kang Suck Whan Kim 《Physica E: Low-dimensional Systems and Nanostructures》2005,28(4):402-411
Optical detected electrophonon resonance (ODEPR) effects in quantum wells of n-GaAs materials are investigated for square potential and parabolic potential, respectively. We also obtain the ODEPR conditions as functions of confinement frequency in parabolic potential and well-width in square potential for the various photon frequencies, respectively. In particular, anomalous behaviors of the ODEPR lineshape such as the splitting of ODEPR peaks for incident photon frequency are discussed. Furthermore, we obtain the selection rules for transition in quantum wells of two different potentials, respectively. 相似文献
972.
Six peptides with various phosphorylation sensitivities for protein kinase A (PKA) were used for the simultaneous analysis of phosphorylated peptides using matrix-assisted laser desorption/ionization-time-of-flight (MALDI-TOF) mass spectrometry. The mixture of six peptides was reacted with PKA and was analyzed by MALDI-TOF mass spectrometry. The intensity of all peaks except one phosphorylated peptide peak was very low (<20%). Moreover, we examined whether the addition of diammonium citrate to CHCA matrix at concentrations of 1–20 mg mL?1 can increase the peak intensity of peptides and phosphorylated peptides. The addition of diammonium citrate increased the peak intensity of peptides and phosphorylated peptides, but an increase in the intensity was unsatisfactory. Our study strongly suggests that MALDI-TOF mass spectrometry is not suitable for the simultaneous analysis of phosphorylated peptides. 相似文献
973.
We demonstrate a bidirectional WDM self-healing ring network for hub/remote nodes with one fiber. In this network, self-healing can be achieved within 8 ms. The transmission capacity can be doubled in the operating state. 相似文献
974.
On an open interval we follow the paths of a Brownian motion which returns to a fixed point as soon as it reaches the boundary and restarts afresh indefinitely. We determine that two paths starting at different points either cannot collapse or they do so almost surely. The problem can be modelled as a spatially inhomogeneous random walk on a group and contrasts sharply with the higher dimensional case in that if two paths may collapse they do so almost surely. 相似文献
975.
In this article, a class of nonlinear evolution equations – reaction–diffusion equations with time delay – is studied. By
combining the domain decomposition technique and the finite difference method, the results for the existence, convergence
and the stability of the numerical solution are obtained in the case of subdomain overlap and when the time-space is completely
discretized.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
976.
Vazid Ali Raminder Kaur Sukhmehar Singh H.P.S. Kang M. Husain 《Journal of Physics and Chemistry of Solids》2006,67(4):659-664
The structural modification and properties of polymeric materials are of utmost importance in deciding their applications. In the present study, the synthesis of polyaniline (PANI) has been carried out via chemical oxidation in acidic medium by potassium-dichromate and the yield of synthesized polyaniline was found to be 75-80%. The copper per chlorate tetrabenzonitrile salt (CuClO4·4BN) used for chemical doping in synthesized polyaniline is stable in organic solvent like acetonitrile (AN) and benzonitrile (BN). The effect of Cu+1 oxidation state (dopant) in polyaniline has been characterized by FTIR. Electrical and dielectric measurements show the decrease in the intensity of the Cu+1 salt signal and the appearance of a radical signal due to the formation of oxidative coupled in polymeric species. Electrical and dielectric properties of doped polyaniline samples show significant changes due to the effect of dopant (CuClO4·4BN). It is observed that the conductivity is contributing both by formation of ionic complex and particularly dominated by electronic due to the mobility of charge carriers along the polyaniline chain. 相似文献
977.
978.
Jong-Chul Park Bongkoo Kang 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1997,25(3):499-506
Magnetic and collisional effects on capacitive radio frequency (RF) discharges for magnetically enhanced reactive ion etching (MERIE) are investigated. Using simplified plasma and sheath models, a collisional magnetic-sheath equation that governs the sheath dynamics under a de magnetic field crossed with a sinusoidal RF electric field is obtained. The sheath equation includes global effects of the bulk plasma. Together with the power-balance equation and the particle-conservation equation, the sheath equation is used to extract a circuit model and predict the electrical behavior of MERIE reactors. Numerical results on the plasma density and the power in MERIE reactors agree well with reported experimental results and the circuit model describes the repeated discharge properties well 相似文献
979.
Jong-Chul Park Bongkoo Kang 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1997,25(6):1398-1405
Modeling and measurement results of the RF input impedance of a helical resonator discharge are given. A simple microstrip transmission line model is used to extract an equivalent circuit of a helical resonator discharge. The transmission line model consists of a grounded cylinder for RF shielding, a helical copper coil for RF heating, and a high density plasma. Transmission line parameters for an experimental helical resonator discharge chamber are extracted, and the results are compared with the measured results. The measured transmission line parameters for the experimental reactor are the characteristic impedance of 200 Ω, the attenuation constant of 6×10-3 Np/m, and the wave number of 0.36 rad/m, which have good agreement with the calculated values 相似文献
980.