Triple-stripe phase-locked diode lasers emitting 100 mw CW with single-lobed far-field patterns

AlGaAs laser arrays with inner stripe configuration have been developed. Transverse mode control was accomplished by introducing nonuniform refractive index and gain distributions, which are built in utilising growth features of liquid-phase epitaxy. The maximum light outputs are 130 mW and 400 mW in CW and pulsed operation, respectively.     

Reflection-wavelength control method for layer-by-layer controlled x-ray multilayer mirrors

A reflection-wavelength control method for a layer-by-layer controlled x-ray multilayer mirror without interface roughness is proposed. The reflection wavelength of the multiperiodic mirror is found to be simply determined by a combination ratio of periodic layers. Multiperiodic x-ray mirrors with reflectance wavelengths at 3.374 nm (C VI 1s-2p) and 3.950 nm (Ca XVIII 3d-5f) are successfully designed.     

Improvement of a physical model for blockage formation of solid–liquid mixture flow with freezing for core safety evaluation of SFRs

The SIMMER code has been developed to analyze event progression during core disruptive accidents (CDAs) in sodium-cooled fast reactors. One of the key phenomena during CDAs is the discharge of molten fuel from the core region which reduces the reactivity effectively. The discharge flow is inhibited by blockage formation due to freezing of the molten fuel. Then, the blockage formation is enhanced by unmolten fuel which forms solid–liquid mixture flow with the molten fuel. A physical model for blockage formation of solid–liquid mixture flow with freezing in the SIMMER code is improved in this study to dissolve some inconsistencies between the modeling and the physical phenomena involved in the solid–liquid mixture flow with freezing for more precise evaluation of CDA. The improved model is validated with a systematical procedure through a benchmark analysis of an experiment. Consequently, experimental penetration behaviors are simulated reasonably by the SIMMER code analysis with the improved model while excessive blockage formation occurred in the analysis with the original model.     

Sodium Dodecylsulphate Electrophoretic Demonstration of Selective Adsorption of Gelatin Polypeptides on Silver Halide Particles-A Qualitative Examination

The gelatin fraction adsorbed on silver iodobromide particles was recovered by dissolution of the particles with sodium thiosulphate. The sodium dodecylsulphate, SDS, electrophoretic pattern of the recovered fraction was clearly different from that of the original gelatin. This is a direct indication of selective adsorption. Extraction of the adsorbed gelatin from the particles was examined with several reagents. Among them, the SDS extract gave a similar electrophoretic pattern to that of the fixation-recovered fraction. Electrophoretic patterns of SDS-extracted fractions from AgCl, AgBr and Agl particles indicate that the absorptions by these silver halides are selective and selectivity by each silver halide is different.     

Asymmetric oxidative coupling polymerization of dihydroxynaphthalene derivatives with cobalt-salen complexes

Summary The oxidative coupling polymerization of dihydroxynaphthalene derivatives with a novel catalyst system, the cobalt(II)-salen complexes, was investigated. For example, the asymmetric polymerization of 2,3-dihydroxynaphthalene with (R,R)-(–)-N,N’-bis(3,5-di-tert-butylsalicylidene)-1,2-cyclohexanediaminocobalt(II) in a dichloromethane-methanol mixed solvent at room temperature for 0.5 h under an oxygen atmosphere, followed by acetylation of the hydroxyl groups, produced a methanol-insoluble polymer with the specific rotation value [α]_D of +165, which was rich in the R-configuration. To estimate the enantioselectivity during the polymerization, the corresponding acetylated dimer product was isolated from a polymerization mixture and determined to be 58% e.e.     

Electrochemical oxidation of cholesterol in acetonitrile leads to the formation of cholesta-4,6-dien-3-one

Cholesterol was shown to be oxidized at the glassy carbon electrode in an acetonitrile–2-propanol mixture and this oxidation reaction was applied to the determination of serum total cholesterol by high-performance liquid chromatography with electrochemical detection (K. Hojo, H. Hakamata, A. Ito, A. Kotani, C. Furukawa, Y.Y. Hosokawa, F. Kusu, J. Chromatogr. A 1166 (2007) 135–141). To gain insight into the detection mechanisms of cholesterol, an electrolytic product of cholesterol was collected and characterized by infrared spectroscopy, one- and two-dimensional nuclear magnetic resonance, and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. The three techniques, together with comparisons of literature spectral data, confirmed the formation of cholesta-4,6-dien-3-one. The conversion of cholesterol to cholesta-4,6-dien-3-one, a four-electron, four-proton electrochemical process, has been proposed as an electrochemical oxidation mechanism of cholesterol in acetonitrile.     

Shape-memory surface with dynamically tunable nano-geometry activated by body heat

Shape-memory surfaces with on-demand, tunable nanopatterns are developed to observe time dependent changes in cell alignment using temperature-responsive poly(?-caprolactone) (PCL) films. Temporary grooved nanopatterns are easily programmed on the films and triggered to transition quickly to permanent surface patterns by the application of body heat. A time-dependent cytoskeleton remodeling is also observed under biologically relevant conditions.