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161.
Near-threshold photoionization of hydrogenlike uranium studied in ion-atom collisions via the time-reversed process 总被引:1,自引:0,他引:1
Stöhlker T Ma X Ludziejewski T Beyer HF Bosch F Brinzanescu O Dunford RW Eichler J Hagmann S Ichihara A Kozhuharov C Krämer A Liesen D Mokler PH Stachura Z Swiat P Warczak A 《Physical review letters》2001,86(6):983-986
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. 相似文献
162.
163.
164.
Masami Sawada Masaharu Ichihara Yoshiro Furukawa Yoshio Takai Takashi Ando Terukiyo Hanafusa 《Tetrahedron letters》1982,23(31):3181-3184
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. 相似文献
165.
166.
Toshihiko Toyama Tokuyuki Ichihara Daisuke Yamaguchi Hiroaki Okamoto 《Applied Surface Science》2007,254(1):295-298
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 SiCx 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 SiCx as well as inserting wide-gap intrinsic a-SiCx at the p-type SiCx/Alq interface are effective for improving device performance. 相似文献
167.
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. 相似文献
168.
Eimutis Juzeliūnas Konstantinas Leinartas Meilutė Samulevičienė Aloyzas Sudavičius Povilas Miečinskas Remigijus Juškėnas Vaclovas Lisauskas 《Journal of Solid State Electrochemistry》2002,6(5):302-310
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 相似文献
169.
170.
Hiroyuki Ito Toru Sakurai Takekiyo Matsuo Toshio Ichihara Itsuo Katakuse 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1997,40(1):102-104
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. 相似文献