Laser patterning and preferential orientation of two-dimensional planar β-BaB2O4 crystals on the glass surface

The laser-induced crystallization method is applied to pattern two-dimensional planar β-BaB₂O₄ crystals on the surface of Sm₂O₃–BaO–B₂O₃ glass. By scanning Yb:YVO₄ fiber lasers (wavelength: 1080 nm) continuously with a small step (0.5 μm) between laser irradiated areas, homogeneous planar β-BaB₂O₄ crystals are patterned successfully, and a preferential growth orientation of β-BaB₂O₄ crystals is confirmed from linearly polarized micro-Raman scattering spectrum and second harmonic intensity measurements. It is found that the crystal growth direction is perpendicular to the laser scanning direction. This relation, i.e., the perpendicular relation, is different from the behavior in discrete crystal line patterning, where the crystal growth direction is consistent with the laser scanning direction. The present study proposes the possibility of the control of crystal growth direction in laser-induced crystallization in glasses.     

Blockade of inflammatory responses by a small-molecule inhibitor of the Rac activator DOCK2

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Highlights? CPYPP binds to DOCK2 DHR-2 domain and inhibits its catalytic activity ? CPYPP inhibits DOCK2-mediated Rac activation in cells ? The structural features of CPYPP required for its inhibitory effect were revealed ? CPYPP inhibits lymphocyte migration and activation in vitro and in vivo     

Batch recording of multiple SQAM signal and self-reference detection technique

Optical Review - The development of holographic data storage is expected as a next-generation large-capacity memory. The recording scheme of spatial quadrature amplitude modulated (SQAM) signal,...     

Comparison of ultrasonic degradation rates constants of methylene blue at 22.8 kHz, 127 kHz, and 490 kHz

Techniques such as solvent extraction, incineration, chemical dehalogenation, and biodegradation have been investigated for the degradation of hazardous organic compounds. We found ultrasound to be an attractive technology for the degradation of hazardous organic compounds in water. However, the effects of ultrasonic frequency on degradation rate constants were not investigated quantitatively. In this study, the degradation process of a model for hazardous organic compound methylene blue was investigated using ultrasonic irradiation. The study focused on the effects of ultrasonic frequency and ultrasonic power on the degradation rate constant. The apparent degradation rate constants were estimated based on time dependence of methylene blue concentration assuming pseudo-first-order kinetics for the decomposition. A linear relationship between the apparent degradation rate constant and ultrasonic power was identified. In addition, the apparent degradation rate constants at frequencies of 127 and 490 kHz were much larger than those at 22.8 kHz. A relationship between the apparent degradation rate constant and the sonochemical efficiency value (SE value) was also found. Based on these results, a simple model for estimating the apparent degradation rate constant of methylene blue based on the ultrasonic power and the SE value is proposed in this study.     

Imaging spectroscopy of the nonequilibrium shock front radiation in air

The nonequilibrium radiation of shock fronts in air is experimentally investigated by means of the imaging spectroscopy technique. Shock velocity ranges from 9.7 to 11.6 km/s and initial pressure from 13.3 to 41.6 Pa. The spectral diagnostic system consists of an imaging spectrograph, a streak camera, a gated image-intensified CCD camera and a personal computer for data acquisition/processing. This spectral diagnostic system is capable of simultaneous wavelength-, intensity- and time-resolved spectroscopic measurements in the nanosecond order. The image processing of the streak images includes a combined smoothing/deconvolution process in the time direction to diminish experimental noise effects and the temporal broadening due to the streak camera entrance slit. Wavelength range is chosen to investigate the first negative band of . “Large” and “slim” streak image types are observed. In the “large” streak images greater contribution from (1-)(1,0) behind the radiation peak is observed. Experimental data are compared with a streak image numerically simulated. The numerical simulation agrees better with the “slim” streak image. Received 7 July 1995 / Accepted 10 January 1996     

Hexagonally ordered mesoporous ternary Li2O-TiO2-P2O5 oxides with high lithium content

Hexagonally ordered mesoporous Li2O-TiO2-P2O5 oxides with high lithium content have been synthesized using surfactant-templated self-assembly; this ternary oxide has been specifically designed to yield a variety of mesoporous frameworks including a nanocomposite, amorphous multicomponent oxide, and almost fully nanocrystalline anatase.     

Conjugate addition of organosiloxanes to alpha,beta-unsaturated carbonyl compounds catalyzed by a cationic rhodium complex

[reaction: see text] A novel, additive-free, and clean conjugate addition reaction of organosiloxanes to alpha,beta-unsaturated carbonyl compounds catalyzed by a cationic rhodium complex in water-containing solvent has been developed. A plausible reaction mechanism involving the additive-free transmetalation step between the rhodium complex and the silicon reagent is proposed.     

Reaction dynamics of V(a4FJ)+NO-->VO(X 4Sigma-)+N studied by a crossed-beam laser-induced fluorescence technique

The dynamics of the reaction, V(a 4FJ)+NO-->VO(X 4Sigma-)+N was studied by using a crossed-beam technique at 16.4 kJ/mol of collision energy. The V atomic beam was generated by laser vaporization and crossed with the O2 beam at a right angle. The laser-induced fluorescence (LIF) for the transition of VO(B 4Pi-X 4Sigma) was used to determine the rotational state distribution of the reaction product in the vibrational ground state. Almost pure V(a 4FJ) beam was obtained by using the mixture of NH3 with N2 as a carrier gas. Comparing the LIF spectra of VO measured for two carrier gases, i.e., NH3N2 and pure N2, it was concluded that the vibrational ground state of VO(X 4Sigma-) is formed almost entirely from the reaction of V(a 4FJ) and the contribution of the metastable V(a 6DJ) is negligible. The observed rotational distribution was similar to a statistical prior prediction, and suggested that the title reaction proceeds via a long-lived intermediate, which is consistent with an electron transfer mechanism.