Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Yokoyama, Tatsunori; Misawa, Keiji*; Okano, Osamu*; Minowa, Haruka*; Fukuoka, Takaaki*
Journal of Radioanalytical and Nuclear Chemistry, 310(1), p.81 - 89, 2016/10
Times Cited Count:1 Percentile:10.71(Chemistry, Analytical)The identification of alkali-rich components in extraterrestrial materials along with their separation from other constituents is indispensable for subsequent cosmochemical and isotopic studies. This paper presents a simple pre-screening method for such materials by autoradiography using imaging plates (IPs), which is applicable to identification of mm-sized samples containing ca. 30 g of potassium in the Yamayo-74442 chondrite. The detection limit of IPs was 1 mBq of K under 49 days exposure. The method provides an opportunity to screen meteorite materials non-destructively and to inexpensively check potassium-rich areas and suitable for the K-Ca and K-Ar (Ar-Ar) age determinations.
Sugai, Hiroyuki; Matsunami, Noriaki*; Fukuoka, Osamu*; Sataka, Masao; Kato, Teruo; Okayasu, Satoru; Shimura, Tetsuo*; Tazawa, Masato*
Nuclear Instruments and Methods in Physics Research B, 250(1-2), p.291 - 294, 2006/09
Times Cited Count:15 Percentile:70.56(Instruments & Instrumentation)We have investigated the effects on electrical properties of Al-doped ZnO (AZO) semiconductor films induced by high-energy heavy ion. The AZO films with c-axis on SiO glass substrate were prepared by a RF-sputter-deposition method at 400 C. Rutherford backscattering spectroscopy shows that the Al/Zn composition and the film thickness are 4 % and 0.3 m. We find that the conductivity monotonically increases from 1.510 to 810 S/cm with increasing the fluence up to 410/cm, as already been observed for 100 keV Ne irradiation. The fluence of 100 keV Ne at which the conductivity takes its maximum is 310/cm (7 dpa). The dpa of 100 MeV Xe at 410/cm is estimated as 0.008. Hence, the conductivity increase by 100 MeV Xe ion is ascribed to the electronic excitation effects.
Fukuoka, Osamu*; Matsunami, Noriaki*; Tazawa, Masato*; Shimura, Tetsuo*; Sataka, Masao; Sugai, Hiroyuki; Okayasu, Satoru
Nuclear Instruments and Methods in Physics Research B, 250(1-2), p.295 - 299, 2006/09
Times Cited Count:24 Percentile:83(Instruments & Instrumentation)We have investigated the effects on electrical and optical properties of Al-doped ZnO (AZO) semiconductor films induced by high-energy heavy ion. The AZO films with c-axis on SiO glass substrate were prepared by a RF-sputter-deposition method at 400 C. Rutherford backscattering spectroscopy shows that the Al/Zn composition and the film thickness are 4 % and 0.3 m. No appreciable change was observed in optical transparency. We find that the conductivity monotonically increases from 1.510 to 810 S/cm with increasing the fluence up to 410/cm, as already been observed for 100 keV Ne irradiation. The fluence of 100 keV Ne at which the conductivity takes its maximum is 310/cm (7 dpa). The dpa of 100 MeV Xe at 410/cm is estimated as 0.008. Hence, the conductivity increase by 100 MeV Xe ion is ascribed to the electronic excitation effects.
Matsunami, Noriaki*; Fukuoka, Osamu*; Shimura, Tetsuo*; Sataka, Masao; Okayasu, Satoru
Nuclear Instruments and Methods in Physics Research B, 230(1-4), p.507 - 511, 2005/04
Times Cited Count:14 Percentile:67.94(Instruments & Instrumentation)no abstracts in English