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121.
Abstract We propose an approach to manipulate the convergence in multiple solutions of phase conjugate reflectivity in photorefractive four-wave mixing. Although a method forcibly adding a π-phase shift to an incident beam has been already proposed to control the reflectivity, some restrictions have been required in the boundary conditions for the successful operation. Here, we control the reflectivity with the boundary conditions in which the phase shift operation is ineffective by itself. In our method, the phase shift operation is combined with the procedure of turning an incident beam on and off. With a numerical analysis of four-wave mixing, we show that our new approach brings drastic change in the spatial distribution of the index grating and leads the phase conjugate reflectivity which was not manipulated previously. 相似文献
122.
123.
Kimiyoshi Ichida Yoshihiro Amaya Ken Okamoto Takeshi Nishino 《International journal of molecular sciences》2012,13(11):15475-15495
Xanthine oxidoreductase (XOR) catalyzes the conversion of hypoxanthine to xanthine and xanthine to uric acid with concomitant reduction of either NAD+ or O2. The enzyme is a target of drugs to treat hyperuricemia, gout and reactive oxygen-related diseases. Human diseases associated with genetically determined dysfunction of XOR are termed xanthinuria, because of the excretion of xanthine in urine. Xanthinuria is classified into two subtypes, type I and type II. Type I xanthinuria involves XOR deficiency due to genetic defect of XOR, whereas type II xanthinuria involves dual deficiency of XOR and aldehyde oxidase (AO, a molybdoflavo enzyme similar to XOR) due to genetic defect in the molybdenum cofactor sulfurase. Molybdenum cofactor deficiency is associated with triple deficiency of XOR, AO and sulfite oxidase, due to defective synthesis of molybdopterin, which is a precursor of molybdenum cofactor for all three enzymes. The present review focuses on mutation or chemical modification studies of mammalian XOR, as well as on XOR mutations identified in humans, aimed at understanding the reaction mechanism of XOR and the relevance of mutated XORs as models to estimate the possible side effects of clinical application of XOR inhibitors. 相似文献
124.
125.
H. Okamoto 《Journal of Phase Equilibria and Diffusion》2012,33(2):162-162
126.
127.
Abstract The dynamic properties of doubly-scattered speckles produced at the image plane have been investigated using a scattering model that consists of a coherent Gaussian beam, a cascade of two moving diffusers and a single imaging lens. Dependence of the fluctuation speed of time-varying image speckles on the velocities of the diffusers is found to change with the size of illuminating speckles and the width of the point-spread function of the imaging lens. When the point-spread function and the focal position satisfy certain conditions, three kinds of velocity information—the velocity of each diffuser, the average velocity of the diffusers and the velocity difference between the diffusers—can be obtained by measuring a temporal correlation length of the time-varying speckle intensity. Experimental results confirm the theoretical predictions. 相似文献
128.
H. Okamoto 《Journal of Phase Equilibria and Diffusion》2012,33(5):415-416
129.
H. Okamoto 《Journal of Phase Equilibria and Diffusion》2011,32(4):389-390
130.
Hirobumi Shibata Tomoaki Morita Taku Ogura Keishi Nishio Hideki Sakai Masahiko Abe Mutsuyoshi Matsumoto 《Journal of Materials Science》2009,44(10):2541-2547
Mesostructured zirconia particles having monoclinic-type crystalline walls were prepared using a low-temperature crystallization
technique. Crystalline zirconia particles with highly-ordered mesostructures were obtained through the sol–gel process of
zirconium sulfate tetrahydrate at 333 K in the presence of molecular self-assemblies of cetyltrimethylammonium bromide (CTAB)
or mixtures of CTAB and anionic molecules such as sodium dodecyl sulfate and sodium p-toluenesulfonate. Variations in the molar ratios of CTAB and the chemical species of anionic molecules led to the variations
in the periods of highly-ordered zirconia having crystalline walls. Calcination of the mesostructured zirconia particles prepared
using templates consisting solely of CTAB yielded crystalline mesoporous zirconia particles. 相似文献