Luminescence fatigue and optically detected magnetic resonance in amorphous silicon-hydrogen alloys

Fatigue of the luminescence in amorphous SiH alloys has been investigated as a function of dangling bond density and of hydrogen content at 2 K. Optically detected magnetic resonance measurements have also been carried out to elucidate the origin of the fatigue effect for those samples.     

Radiative and nonradiative recombination processes in hydrogenated amorphous silicon as elucidated by optically detected magnetic resonance

Radiative and nonradiative recombination processes have been investigated by measurements of optically detected magnetic resonance at 2 K in hydrogenated anorphous silicon. Relevant processes are discussed on the basis of the experimental results.     

Spallation of niobium by 12 GeV protons

Cross sections for the production of approximately 50 radionuclides in the interaction of niobium with 12 GeV protons were determined by the activation technique. The results were parametrized in terms of a 6-parameter equation which reproduced the measured charge-dispersion and mass-yield curves.     

Elemental analysis of airborne fine particles collected at the roadside of an arterial road

Airborne particulate matter was collected at the intersection of Industrial Road in Kawasaki-city, Kanagawa, Japan using a 12-stage low-pressure impactor. High concentrations of airborne particulate matter have been observed in this area. The collected samples were analyzed for 34 elements by instrumental neutron activation analysis (INAA), and data on the elemental concentrations were obtained. High concentrations of fine particles of As, Br, Sb, V, and Zn were observed. It was further observed that these fine particles were originated predominantly from the wear of tires and brakes, and not from automobile exhaust emissions.     

Study on the combustion kinetic characteristics of biomass tar under catalysts

TG and DTA experiments were performed to investigate the biomass tar combustion behavior in coexistence of dolomite and mayenite at two different heating rates as 5 and 15°C min⁻¹. Different reaction kinetic mechanisms with the classical Arrhenius model were used to treat TG data, and showed that the first-order combustion model fitted the data well. Three stages combustion model was proposed and applied for the calculation of kinetics parameters successfully. The starting temperature of high temperature combustion stage moved up near 100°C because of the coexistence catalysts, and the combustion amount of biomass of the stage also improved nearly 10 mass%. By calculation a uniform trend of decreasing activation energies was observed with the addition of dolomite and mayenite, and also greatly improved the amount and speed of tar combustion process.     

Voltammetric evaluation of the binding between wheat germ agglutinin and thionine/glucose-modified magnetic microbeads.

The binding between glucose residues and wheat germ agglutinin (WGA) on thionine/glucose-modified magnetic microbeads was evaluated using voltammetry. Thionine is an electroactive compound and has two amino groups. Thionine was immobilized to magnetic beads via cross-linking of the amino groups on the beads with an amino group on thionine. Glucose was bound to the other amino group of thionine via the formation of a Schiff base. The beads were only several micrometers in size the same size, as cells. WGA-binding to glucose on the bead surface blankets the thionine moiety. Thus, WGA-binding could be detected as a decrease in peak current of the thionine moiety.     

Iridium complex-catalyzed addition of water and alcohols to non-activated terminal alkynes

The addition of water and alcohols to non-activated terminal alkynes was found to be promoted by an iridium complex combined with Lewis acid and phosphite. Thus, terminal alkynes reacted with water or alcohols to give ketones or ketals, respectively, in good to excellent yields. α,ω-Diyne like 1,7-octadiyne was converted into 1-(2-methyl-cyclopent-1-enyl)ethanone through the intramoleculer aldol condensation of the resulting 2,7-octanedione induced by Lewis acid.     

Acid catalyzed reduction of nitrosobenzene by 3,5-dipyrrolidinocarbamoyl-N-benzyl-1,4-dihydropyridine as a nadh analog

Acid catalyzed reduction of substituted nitrosobenzenes to the hydroxylamines by 3,5-dipyrrolidinocarbamoyl-N-benzyl-1,4-dihydropyridine has been studied in anhydrous acetonitrile.