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231.
Yutaka Fujimoto Hiroaki Tanno Shigetomo Yoshida Masanobu Shirai Kouichirou Tanaka Yutaka Kawabe Eiichi Hanamura 《Journal of luminescence》2008,128(3):282-286
Spinel MgAl2O4 crystals doped with transition metals show charge-transfer transitions for Ti:MgAl2O4 on one hand and multiplet transitions of (3d)-electrons for Mn:, Fe:, and Co:MgAl2O4 on the other hand. We will show that optical responses of V:MgAl2O4 are closer to those of Ti:MgAl2O4 and also that white emission spectrum is observed. The microscopic process of the white emission is also proposed. 相似文献
232.
233.
A newly designed jet-type, water-cooled heat sink (the funryu heat sink, meaning fountain flow in Japanese) yielded 255-W cw laser output at 808 nm from a 1-cm bar made from InGaAsP/InGaP quantum-well active layers with a 67% fill factor [70 quantum-well laser diode (LD) array along the 1-cm bar]. A funryu heat sink measuring 1.1 mm in thickness gave the LD 0.25 degrees C/W thermal resistance, one of the lowest values achieved with a 1-cm LD bar. Over a short period of operation, the device reached a maximum cw power of 255 W. To the best of our knowledge, this is the highest power ever achieved in 808-nm LD operation. In the future, the funryu heat sink may be capable of 80-W cw operation over an extended lifetime of several thousand hours. 相似文献
234.
235.
Ion-exclusion/adsorption chromatography of dimethylsulfoxide (DMSO) and its derivatives, i.e., methanesulfinic acid (MSI), methanesulfonic acid (MSA) and sulfuric acid (SA), was developed in order to clear the decomposition mechanism of DMSO on quality-test of TiO2-photocatalyst in water. The separation was achieved by the adsorption effect for DMSO and ion-exclusion effect for MSI, MSA and SA under optimum conditions, using a weakly acidic cation-exchange resin column with 20 mM succinic acid as the eluent. In this system, DMSO and MSI with UV at 195 nm and MSA and SA with conductivity detection were consecutively determined by single injection and single separation column. This method was used to monitor the artificial decomposition of DMSO induced by a photocatalyst. The concentration of DMSO by active oxygens (e.g., OH radical) generated from surface of photocatalyst was found to be decreased through the stoichiometric reaction in the order of MSI, MSA and SA. 相似文献
236.
We used an asymmetric layered system functioning as a plasmon waveguide coupler to couple surface plasmon modes with gap plasmon
modes. The planar system was analyzed by the transfer matrix method to design the optical dimensions of the system. We simulated
the effective mode indexes and H-field distribution of the coupled modes, for different gap widths and refractive indexes. For the calculated modes the propagation
lengths were calculated. Furthermore, a sample structure was fabricated and odd gap plasmon modes were excited with a coupling
prism in an attenuated-total-reflection (ATR) configuration. The mode index measurement showed good agreement with the simulation
data. 相似文献
237.
A zero-valent [M(Ph(2)PCH(2)CH(2)PPh(2))(2)] moiety (M = Mo, W) generated in situ by dissociation of the N(2) ligands in trans-[M(N(2))(2)(Ph(2)PCH(2)CH(2)PPh(2))(2)] can activate pi-accepting organic molecules including isocyanides and nitriles, which undergo the electrophilic attack caused by a strong pi-donation from a zero-valent metal center. Cleavage of a variety of C-X bonds (X = H, C, N, O, P, halogen) also occurs at their electron-rich sites through oxidative addition to form reactive intermediates, which subsequently degradate to yield smaller molecules either bound to or dissociated from the metal center. The mechanism is substantiated unambiguously by isolation of numerous intermediate stages. 相似文献
238.
Wakasa M 《The journal of physical chemistry. B》2007,111(32):9434-9436
The magnetic field effects (MFEs) on photoinduced hydrogen abstraction reactions of benzophenone (BP) with thiophenol (PhSH) in the ionic liquids (ILs) N,N,N-trimethyl-N-propylammonium bis(trifluoromethanesulfonyl) imide (TMPA TFSI), N-methyl-N-propylpyrrolidinium bis(trifluoromethanesulfonyl) imide (P13 TFSI), and N-methyl-N-propylpiperidinium bis(trifluoromethanesulfonyl) imide (PP13 TFSI) were investigated at 296 K by using a nanosecond laser flash photolysis technique under magnetic fields of 0-1.7 T. Large MFEs were observed for the first time in the ILs. In TMPA TFSI, the yield of the benzophenone ketyl radical gradually decreased with increasing magnetic field strength from 0 to 1.7 T, producing a 20% decrease at 1.7 T. 相似文献
239.
240.
Gakuse Hoshina Masanobu Tsuchimoto Shigeru Ohba 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(4):e122-e122
In crystals of the title compound, [Ni(C28H22N2O2)], the coordination geometry around the Ni atom is square planar with a slight tetrahedral distortion. The five‐membered N,N′‐chelate ring adopts a distorted gauche conformation with the two phenyl groups in axial and equatorial orientations. 相似文献