Near-threshold photoionization of hydrogenlike uranium studied in ion-atom collisions via the time-reversed process

Radiative electron capture, the time-reversed photoionization process occurring in ion-atom collisions, provides presently the only access to photoionization studies for very highly charged ions. By applying the deceleration mode of the ESR storage ring, we studied this process in low-energy collisions of bare uranium ions with low- Z target atoms. This technique allows us to extend the current information about photoionization to much lower energies than those accessible for neutral heavy elements in the direct reaction channel. The results prove that for high- Z systems, higher-order multipole contributions and magnetic corrections persist even at energies close to the threshold.     

A simple preparation of 1,3,5-triazine derivatives from 4-pyridones

The reaction of 4-pyridone or 4-quinolone with methyl or benzyl isocyanate in the presence of triethylamine or 1,1,3,3-tetramethylguanidine base gave the corresponding 1,3,5-triazine derivative (e. g., II) in a good yield via stepwise additions.     

Synthesis and characterization of organic/inorganic heterostructure films for hybrid light emitting diode

Thin-film light emitting devices based on organic materials have been gathering attentions for applying a flat-panel display and a solid-state lighting. Alternatively, inorganic technologies such as Si-based thin-film technology have been growing almost independently. It is then expected that combining the Si-based thin-film technology with the organic light emitting diode (OLED) technology will develop innovative devices. Here, we report syntheses of the hybrid light emitting diode (LED) with a heterostructure consisting of p-type SiC_x and tris-(8-hydroxyquinoline) aluminum films and characterization for the hybrid LEDs. We present the energy diagram of the heterostructure, and describe that the use of high dark conductivities of the p-type SiC_x as well as inserting wide-gap intrinsic a-SiC_x at the p-type SiC_x/Alq interface are effective for improving device performance.     

Facile synthesis of quinone epoxides and 5,6-epoxy-4-hydroxy-2-cyclohexenones via the retro-diels-alder reaction

From commercially available quinoes, quinone epoxides and 5,6-epoxy-4-hydroxy-2-cyclohexenones were easily prepared through the retro-Diels-Alder reactions under rather mild conditions.     

Microgravimetric corrosion study of magnetron-sputtered Co-Cr-Mo and Ni-Cr-Mo alloys in an oxygen-containing atmosphere

A quartz crystal microbalance (QCM) has been used for in situ corrosion studies of magnetron-sputtered Co-Cr-Mo and Ni-Cr-Mo alloys, which are of great importance in various technical and medical applications. The corrosion monitoring has been performed in an oxygen-containing atmosphere and in NaCl solution. The alloys were deposited on quartz substrates by means of DC magnetron sputtering. X-ray photoelectron spectroscopy analysis showed that the composition of the deposits was similar to that of the magnetron-sputtering targets. X-ray diffraction revealed an amorphous structure of the sputtered deposits, while the casting alloys had a crystalline structure. The polarization resistance of sputtered alloys in NaCl solution was higher than the activity of conventional alloys, which implied a superior corrosion resistance of the sputtered deposits. Corrosion was initiated by supplying oxygen gas into a wet argon atmosphere and the QCM detected corrosion with nanogram resolution as the increase in mass. Corrosion currents were calculated from the mass versus time curves. The QCM appeared to be an effective tool for corrosive characterization of sputtered alloys in gaseous environments. A corrosion current calculation in solution was complicated by metal transfer to the liquid phase. Electronic Publication     

Observation of doubly charged mercury cluster ions Hg n 2+, n=1-10 using secondary ion mass spectrometry

Mass spectra of doubly charged mercury clusters (m/z=30-1065) were investigated by secondary ion mass spectrometry. Positively charged ions were generated from an amalgam of mercury and silver by bombardment with a xenon ion beam and mass analysis by a grand-scale sector type mass spectrometer. Hg _n ²⁺, n=1-10 and Hg _n +, n =1- 5 were observed. Some doubly charged mercury clusters, (Hg _n ²⁺) survived at least for 0.1 ms.