Low temperature synthesis of TiO2−xNy powders and films with visible light responsive photocatalytic activity

Nitrogen-doped titania powders and films with excellent visible light photocatalytic activity were successfully prepared by an unadulterated ‘low-temperature process’ below 60 °C using mechanochemical doping and oxygen plasma treatment.     

Molecular orbital quantities of conjugated ketenes and influence of structural variations on their electronic features

MO quantities by CNDO/2 method on several valence isomeric ketenes and structurally corresponding allene molecules were calculated to evaluate the influence of structural feature on magnitude of back-donation of oxygen n-electrons in ketene, and to rationalize an unusual cycloaddition involved in diphenyl ketene.     

Amperometric determination of cholinesterase with use of an immobilized enzyme electrode

A choline-sensitive electrode consisting of an immobilized choline oxidase layer and an oxygen electrode is described. Cholinesterase (0.5–60 I.U. l^-1) is measured by addition of acetylcholine, and detection of the choline produced. The precision is 3%, and the electrode is stable for more than 2 weeks (140 assays).     

Reaction of diazonium salts with transition metals : X. Formylation of arenediazonium salts with carbon monoxide and silyl hydrides under palladium catalysis

Arenediazonium tetrafluoroborates (ArN₂BF₄ where Ar = X-C₆H₄; X = H, 2-Me, 3-Me, 4-Me, 4-MeO, 4-MeCO, 4-EtOCO, 2-Ph, 2-Cl, 3-Cl, 4-Cl, 4-Br, 4-I, 3-NO₂ and 4-NO₂) were easily converted to aromatic aldehydes (ArCHO) in good yields through the palladium-catalyzed reaction with CO and Et₃SiH or polymethylhydrosiloxane (PMHS) at room temperature.     

The specific heat of linear polyethylene after annealing at low temperatures

After annealing at low temperature, linear polyethylene displays an unusual feature in its specific heat curve. On heating, a maximum is observed just above the annealing temperature. The magnitude of this excess specific heat is dependent on the initial level of crystallinity and the temperature and time of annealing. The maximum does not reappear on subsequent cooling followed by rapid heating and represents the formation and disappearance of an unstable structure. These results can be interpreted as a crystallization-melting phenomenon and are consistent with the wide-angle x-ray diffraction patterns. The optimum effects are observed in the β-region (?50°C to 0°C) and could possibly lead to complications in interpreting other phenomena in this temperature range.     

Refractive indices of LiNb1−yTayO3 single crystals

The refractive indices of LiNb_1?yTa_yO₃ single crystals grown by the Czochralski method were determined in the wavelength range 5893 to 10600 Å at 20 ± 0.5°C. The results indicate that a single crystal (0.95 < y < 0.96) has zero birefringence. Such composition is independent of the wavelength.