Pressure-induced superconductivity in beta- Na (0.33) V(2)O(5) beyond charge ordering

We report the discovery of a new superconducting phase in highly correlated 3d electron systems. The compound is beta-vanadium bronze, beta- Na0.33V 2O5, in which the charge-ordered phase collapses under hydrostatic high pressure and a pressure-induced superconducting phase appears around T(S C)=8 K, P=8 GPa. This report presents the first observation not only of superconductivity in vanadium oxides but also of a phase transition from charge ordered to superconducting on a pressure-temperature (P- T) plane. The phase diagrams seem to have universal aspects across the classes of materials. This indicates a profound physics of superconductivity in highly correlated electron systems.     

Direct probe of the bent and linear geometries of the core-excited Renner-Teller pair states by means of the triple-ion-coincidence momentum imaging technique

The doubly degenerate core-excited Pi state of CO2 splits into two due to static Renner-Teller effect. Using the triple-ion-coincidence momentum imaging technique and focusing on the dependence of the measured quantities on the polarization of the incident light, we have probed, directly and separately, the linear and bent geometries for the B1 and A1 Renner-Teller pair states, as a direct proof of the static Renner-Teller effect.     

Coherent magnetic oscillation in the spin ladder system alpha(')- NaV2O5

We report the first observation of coherent magnetic excitations in a spin ladder system NaV2O5 by using femtosecond time-domain spectroscopy. A pronounced coherent oscillation is observed at 127 cm(-1) (nearly twice the spin gap energy) and assigned to a two-magnon bound state, based on the temperature dependence of the intensity below the charge ordering phase transition at T(C) = 34 K. This mode can be observable only when circularly polarized light is used as a pump or a probe beam, suggesting that it corresponds to a spin-flip excitation from the singlet ground state. A phonon mode strongly coupled to the spin state is also found at 303 cm(-1).     

Light attenuation in a semitransparent foam sheet-Thickness measurement for industrial use

An optical method for measuring the thickness of heterogeneous materials has been studied. The method is based on the light attenuation theory. A complete system has been constructed in order to demonstrate the applicability of the present method for industrial use. The experimental set-up consists of semiconductor lasers, focusing lenses, photo-diodes serving as a power meter and a personal computer with an A/D converter for data acquisition. Averaging of numerous measurements is required in the present method because the heterogeneous cell structure of the foam material yields large fluctuations in transmitted light levels. The fluctuations can be reduced to below 1% of the transmitted light power by 80 times averaging. The error of the measurement is considered to be a few tens of micrometers in thickness. The present system is capable of sampling data at a rate of 400 Hz and has been successfully applied to a manufacturing process.     

Die Copolymerisation von Vinylhydrochinon und Acrylnitril mit Tri-n-Butylboran

Ohne Zusammenfassung     

Hochtemperaturphosphidierung von Eisen-Nickellegierungen mittels Phosphordampf

High Temperature Phosphidation of Iron-Nickel Alloys by Phosphorus Vapor A study was undertaken concerning the products and kinetics in the phosphidation of iron-nickel alloys with various ratios of metallic constituents at 700° in phosphorus vapor at 1 atm by a sealed-tube method. X-ray diffraction patterns and an electron microprobe analysis of the products showed that the phosphide-layer structure reaches the expression of NiP₂ ～ Ni₆P₅/Ni₂P, Fe₂P/(Fe? Ni alloy). The phosphidations proceeded according to a parabolic rate law for all the compositions of the alloy. A marker experiment indicated that the diffusing species was not phosphorus but metals. The rate constant decreased with an increase in the content of iron in the alloy.     

Synthese von Polyamiden aus aktiven Diestern von 3-Hydroxybenzothiophen-1,1-dioxid und Diaminen unter milden Bedingungen

Ohne Zusammenfassung