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61.
This paper gives a new characterization of Euler's gamma function from the aspect of complex analysis. To this end the Gauss multiplication formula is used.  相似文献   
62.
We have analyzed the transfer efficiency of ballistic electron emission microscopy (BEEM), taking the finite spot size of the emitted electron beam from scanning probes into account. Three-dimensional diffraction from an aperture at a surface-metal/air interface is introduced to model an effect caused by the finiteness of spot size. As a general trend, the diffraction decreases BEEM transfer efficiency. The diffraction effect increases as the spot size decreases and the air-gap distance increases. In a Au/GaAs sample, BEEM transfer efficiency markedly deteriorates down to 6% of the value derived from a conventional planar tunneling theory when a spot size of 0.2 nm, an air-gap distance of 0.6 nm, and an electron energy of 0.2 eV, measured from the bottom of the GaAs conduction band, are assumed. BEEM transfer efficiency is markedly dependent on the spot size of the emitted hot electron. This result indicates that the BEEM current depends on the spatial resolution of the scanning probe, that is, the condition of the tip apex.  相似文献   
63.
We study a way ofq-deformation of the bi-local system, the two-particle system bounded by a relativistic harmonic-oscillator type of potential, from both points of view of mass spectra and the behavior of scattering amplitudes. In our formulation, the deformation is done so thatP 2, the square of center-of-mass momentum, enters into the deformation parameters of relative coordinates. As a result, the wave equation of the bi-local system becomes nonlinear with respect toP 2; then, the propagator of the bi-local system suffers significant change so as to get a convergent self energy to the second order. The study is also made on the covariantq-deformation in four-dimensional spacetime.  相似文献   
64.
A catalyst deposited on a polypropylene sheet having an activity of almost the same level as commercially available Pd black and capable of promoting hydrogenolysis-free hydrogenation was developed.  相似文献   
65.
The utility of the absorption promoters, sodium glycocholate (GC-Na), ethylenediamine dihydrochloride (EDTA-2Na), sodium caprylate (Cap-Na) and sodium salicylate (Sal-Na), in the intranasal administration of human fibroblast interferon-beta (HuIFN-beta) in rabbits was investigated. The optimal amount of added EDTA-2Na, Cap-Na and Sal-Na with respect to HuIFN-beta was examined for nasal absorption in the powder dosage form. Formulations of HuIFN-beta with GC-Na showed greatly enhanced intranasal HuIFN-beta absorption, as compared to the other absorption promoters. The results of a stability study on HuIFN-beta in homogenates of nasal mucosa suggested that GC-Na behaved as a hydrolysis inhibitor in the nasal mucosa and maintained the activity of HuIFN-beta.  相似文献   
66.
An alkylyttrium complex supported by an N,N′-bis(2,6-diisopropylphenyl)ethylenediamido ligand, (ArNCH2CH2NAr)Y(CH2SiMe3)(THF)2 (1, Ar = 2,6-iPr2C6H3), activated an ortho-phenyl C–H bond of 2-phenylpyridine (2a) to form a (2-pyridylphenyl)yttrium complex (3a) containing a five-membered metallacycle. Subsequently, a unique C(sp2)–C(sp2) coupling of 2-phenylpyridine proceeded through a bimetallic yttrium intermediate, derived from an intramolecular shift of the yttrium center to an ortho-position of the pyridine ring in 3a, to yield a bimetallic yttrium complex (4a) bridged by two-electron reduced 6,6′-diphenyl-2,2′-bipyridyl. Aryl substituents at the ortho-position of the pyridine ring were key in order to destabilize the μ,κ2-(C,N)-pyridyldiyttrium intermediate prior to the C(sp2)–C(sp2) bond formation.  相似文献   
67.
We propose a novel application of the Wang-Landau method (WLM) for multicanonical molecular dynamics (McMD) simulations. Originally, WLM was developed for Monte Carlo (MC) simulations. Fundamentally, WLM remarkably reduces simulation efforts because it estimates the optimal multicanonical energy function automatically. When WLM is applied to McMD, not only the multicanonical energy but also energy gradient must be estimated adequately. However, because of the rugged multicanonical energy function at the early simulation stage, applications of WLM for MD simulations are difficult and require a smoothing procedure: simulation efforts such as cubic-spline extrapolation and gathering multiple preruns are utilized for smoothing. We propose a simple and effective smoothing method that requires only one additional equation and two time-dependent parameters. As a result, our method produced the correct multicanonical energy function and succeeded in the flat sampling of a small biomolecule with reduced simulation effort.  相似文献   
68.
A new technique for the preparation of a highly clear and transparent emulsified aqueous solution containing immiscible monomer droplets with diameters of a few tens of nanometres under surfactant-free conditions using tandem acoustic emulsification is described. Highly conductive transparent polymer films were successfully prepared from such an emulsified solution.  相似文献   
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