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71.
This paper proposes a practical measurement system for bidirectional reflectance distribution functions (BRDFs) of a three-dimensional
(3D) object with a linear light source. Using the linear light source, the proposed system can reduce the number of image
acquisitions which are necessary for an estimation of the spatially-varying BRDFs of the object. Furthermore, the size of
the proposed system is much smaller than a conventional system which uses a parallel light. In this proposed system, the light
field of the linear light source is previously measured to determine direction and radiance of incident rays to each point
of the object, because the direction and radiance are not constant at each point. Using the proposed system, the BRDF of a
point of flat objects was experimentally measured, and results showed validation of the estimation accuracy of the proposed
system. Measurement efficiency of the proposed system was also evaluated by comparing reflectance model parameters estimated
by the conventional and proposed systems. For the estimation, the reflectance function of a 3D object was measured by both
systems. The estimation accuracy of the proposed method was also evaluated by comparing among a real image and rendered 3D
objects of the conventional and proposed methods. 相似文献
72.
Kenji Okitsu Hiroshi Nakamura Norimichi Takenaka Hiroshi Bandow Yasuaki Maeda Yoshio Nagata 《Research on Chemical Intermediates》2004,30(7-8):763-774
The reaction of 1,1-diphenyl-2-picrylhydrazyl (DPPH) with a radical intermediate was investigated in the sonolysis of several organic solvents. The rate of the DPPH consumption in the sonolysis of methanol obeyed first-order kinetics at low concentrations of DPPH, while the rate became zero-order as the concentration of DPPH further increased. The radical trapping reactions of DPPH were found to be considerably slow compared with the formation of hydrogen molecules in the sonolysis of alcohols and hydrocarbons. These results indicate that H atoms formed in the solvent sonolysis quickly react to form stable molecules such as hydrogen in the cavitation bubble and/or at the interface region. The rates of the DPPH consumption were strongly dependent on the vapor pressure and relative evaporation rate of the solvents. It was proposed that the optimum vapor pressure exists for an effective formation of radical species. 相似文献
73.
Hirohiko Sato Norimichi Kojima 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4):361-366
Abstract Electronic properties of Na3Cu4S4, K3Cu8S6, Rb3Cu8S6, Rb3Cu8Se6, KCu3S2, and CsCu3S2 are discussed on the basis of the measurements of resistivity and thermopower. 相似文献
74.
Tada M Kojima N Izumi Y Taniike T Iwasawa Y 《The journal of physical chemistry. B》2005,109(20):9905-9916
Vanadium monomers with chiral tridentate Schiff-base ligands were supported on SiO(2) through a chemical reaction with surface silanols, where we found a new chirality creation by the self-dimerization of the vanadyl complexes on the surface. The chiral self-dimerization and the role of surface silanols in the self-assembly were investigated by means of X-ray absorption near-edge structure (XANES), extended X-ray absorption fine structure (EXAFS), diffuse-reflectance ultraviolet/visible (DR-UV/VIS), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FT-IR), electron spin resonance (ESR), and density functional theory (DFT) calculations. The surface vanadyl complexes had a distorted square-pyramidal conformation with a V=O bond. FT-IR spectra revealed that the Ph-O moiety of Schiff-base ligands was converted to Ph-OH by a surface-concerted reaction between the vanadium precursors and surface SiOH groups. The Ph-OH in an attached vanadyl complex interacted with a COO moiety of another vanadyl complex by hydrogen bonding to form a self-dimerized structure at the surface. The interatomic distance of V-V in the surface self-assembly was evaluated to be 0.40 +/- 0.05 nm by ESR after O(2) adsorption. The self-dimerized V structure on SiO(2) was modeled by DFT calculations, which demonstrated that two vanadium monomers with Ph-OH linked together by two hydrogen bonds and their V=O groups were directed opposite to each other. The surface self-dimerization of the vanadium precursors fixes the direction of the V=O bond and the plane of the Schiff-base ligand. Thus, a new chiral reaction field was created by two types of chirality: the chiral Schiff-base ligand and the chiral V center. We have also found that the chiral self-dimerized vanadyl complexes exhibit remarkable catalytic performance for the asymmetric oxidative coupling of 2-naphthol: 96% conversion, 100% selectivity to 1,1'-binaphthol (BINOL), and 90% enantiomeric excess (ee). Increasing the vanadium loading on SiO(2) caused a dramatic swell of enantioselectivity, and the maximum 90% ee was observed on the supported catalyst with the full coverage of the vanadyl complex (3.4 wt % vanadium). This value is equivalent to the maximum ee reported in homogeneous catalysis for the coupling reaction. Furthermore, the supported vanadium dimers were reusable without loss of the catalytic performance. To our knowledge, this is the first heterogeneous catalyst for the asymmetric oxidative coupling of 2-naphthol. 相似文献
75.
A series of 5-aminolevulinic acid and its alkylester methanesulfonates was exploited to photodynamic therapy(PDT) of human lymphocytic cells, U-937 in vitro. The PDT efficiency is influenced by the concentration and incubation time. Generally, for ALA and its alkylester methanesulfonates, the cell survival rate decreases and the accumulation ability of PpIX increases with the concentration and incubation time. We found that the longer carbon chain methanesulfonates(C5-S, C6-S, C8-S) exhibit better PDT effec... 相似文献
76.
Norimichi Hirano 《NoDEA : Nonlinear Differential Equations and Applications》2009,16(2):159-188
In this paper, we consider the multiple existence of nonradial positive solutions of coupled nonlinear Schr?dinger system
where μ1, μ2 > 0 with and β < 0.
It is known that the solutions of (P) is not necessarily radial [12]. We show that problem (P) has multiple nonradial solutions
in case that |β| is sufficiently small.
相似文献
77.
Takenaka N Takahashi I Suekane H Yamamoto K Sadanaga Y Bandow H 《The journal of physical chemistry. A》2011,115(50):14446-14451
A reaction of ammonium nitrite in ice was investigated. Upon freezing, some nitrite is oxidized by dissolved oxygen and some nitrite reacts with ammonium to produce nitrogen and water in a denitrification reaction. The former reaction was accelerated only during freezing, and the latter one was accelerated even after the whole sample was frozen. The denitrification reaction proceeded at very low concentration in ice, which were conditions under which the reaction would not proceed in solution. The nitrogen production increased linearly with increasing initial concentration of ammonium nitrite. The concentration factor in the unfrozen solution in ice was estimated to be 50.6 when the initial concentration was 0.5 mmol dm(-3), as obtained from comparison of reaction rates in solution and in ice. A new method for determination of the activation energy is proposed that gives a value of 53 to 61 kJ mol(-1) for denitrification. The reaction order of the denitrification process is also determined using our method, and it is concluded to follow third-order kinetics. 相似文献
78.
Norimichi Hirano 《Journal of Functional Analysis》2011,261(12):3612-3632
We will show that the problem
79.
Norimichi Hirano 《Journal of Differential Equations》1983,47(2):163-179
An energy decay rate is obtained for solutions of wave type equations in a bounded region in Rn whose boundary consists partly of a nontrapping reflecting surface and partly of an energy absorbing surface. 相似文献
80.