The design secret of Kyokusui-no-En’s meandering channel

The purpose of this study is to investigate the characteristics of the flow through the Jonangu channel which is used for ceremonial game called as ‘Kyokusui-no-En’ in Japanese. The geometry of the channel is measured, a visualization technique is used to measure the actual flow characteristics, and then a numerical flow model is used to represent the flow including unsteady flow characteristics. Numerical model of drifting cup is introduced to investigate an interaction between flow and motion of the cup. Finally, the intention of the channel design is interpreted from the viewpoint of fluid mechanics using observed and calculated results.     

Masking effect of potassium iodide on the interferences in the atomic-absorption spectrophotometric determination of antimony utilizing stibine generation by sodium borohydride tablet reduction

Summary The masking effect of potassium iodide with or without hydroxylamine on the interferences in the atomic-absorption spectrophotometric determination of antimony via its hydride by sodium borohydride tablet reduction has been studied. It has been well known in the conventional colorimetric method [21] that both potassium iodide and stannous chloride completely suppress the evolution of stibine. However, in this sodium borohydride tablet reduction, potassium iodide plays a role in masking the interferences of not only stannous chloride but also other numerous ions. By the procedure established here, the calibration curve was linear up to a concentration of 0.04g/ml of antimony with the coefficient of variation of 2.4 %. The method was successfully applied to the determination of antimony in a river sediment.

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Maskierende Wirkung von Kaliumiodid auf Störungen bei der AAS-Bestimmung von Antimon durch Stibinerzeugung mit Hilfe der Natriumborhydridreduktion

Zusammenfassung Es ist bekannt, daß bei der colorimetrischen Bestimmungsmethode [21] sowohl KI als auch SnCl₂ die Entwicklung von Stibin vollständig verhindern. Bei der hier beschriebenen Reduktion mit Hilfe einer NaBH₄-Tablette maskiert jedoch KI (mit oder ohne Hydroxylaminzusatz) Störungen durch SnCl₂ sowie durch zahlreiche andere Ionen. Die Eichkurve verläuft bis zu 0,04 g Sb/ml linear. Der Variationskoeffizient beträgt 2,4 %. Als Anwendungsbeispiel wird die Antimonbestimmung in Flußsedimenten erwähnt.

     

Strange giant resonance in (K −,π−) reaction

We point out a possibility of strange giant resonances that can be excited by the (K ^?,π^?) reaction on nuclear targets. Recent experimental data on⁴⁰Ca are analyzed from this point of view.     

A coordination gelator that shows a reversible chromatic change and sol-gel phase-transition behavior upon oxidative/reductive stimuli

A novel coordination gelator exhibits reversible chromatic and sol-gel phase-transition phenomena triggered by thermal and chemical stimuli.     

Freie Diffusion in einem Zweikomponenten-System, in dem Volumen?nderung beim Mischen eintritt

Ohne Zusammenfassung     

Substituent effects of iridium complexes for highly efficient red OLEDs

This study reports substituent effects of iridium complexes with 1-phenylisoquinoline ligands. The emission spectra and phosphorescence quantum yields of the complexes differ from that of tris(1-phenylisoquinolinato-C2,N)iridium(iii)(Irpiq) depending on the substituents. The maximum emission peak, quantum yield and lifetime of those complexes ranged from 598-635 nm, 0.17-0.32 and 1.07-2.34 micros, respectively. This indicates the nature of the substituents has a significant influence on the kinetics of the excited-state decay. The substituents attached to phenyl ring have an influence on a stability of the HOMO. Furthermore, those substituents have effect on the contribution to a mixing between 3pi-pi* and (3)MLCT for the lowest excited states. Some of the complexes display the larger quantum yield than Irpiq, which has the quantum yield of 0.22. The organic light emitting diode (OLED) device based on tris [1-(4-fluoro-5-methylphenyl)isoquinolinato-C2,N]iridium(iii)(Ir4F5Mpiq) yielded high external quantum efficiency of 15.5% and a power efficiency of 12.4 lm W(-1) at a luminance of 218 cd m(-2). An emission color of the device was close to an NTSC specification with CIE chromaticity characteristics of (0.66, 0.34).     

Effect of disorder outside the CuO2 planes on Tc of copper oxide superconductors

The effect of disorder on the superconducting transition temperature T(c) of cuprate superconductors is examined. Disorder is introduced into the cation sites in the plane adjacent to the CuO2 planes of two single-layer systems, Bi(2.0)Sr(1.6)Ln(0.4)CuO(6+delta) and La(1.85-y)Nd(y)Sr0.15CuO4. Disorder is controlled by changing rare earth (Ln) ions with a different ionic radius in the former, and by varying the Nd content in the latter with the doped carrier density kept constant. We show that this type of disorder works as weak scatterers in contrast to the in-plane disorder produced by Zn, but remarkably reduces T(c), suggesting novel effects of disorder on high-T(c) superconductivity.