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Ishiyama, Shintaro; Imahori, Yoshio*; Itami, Jun*; Koivunoro, H.*
Global Journal of Medical Research; F, 15(4), p.1 - 5, 2015/11
In defining the biological effects of the neutron capture reaction, we have proposed a deterministic parsing model (ISHIYAMA-IMAHORI model) to determine the Compound Biological Effectiveness (CBE) factor in Borono-Phenyl-Alanine (BPA)-mediated Boron Neutron Capture Therapy (BNCT). To determine the CBE factor, we derived new calculation formula founded on the deterministic parsing model with three constants, CBE0, F, n and the eigen value Nth/Nmax. where, Nth and Nmax are the threshold value of boron concentration of N and saturation boron density. In order to determine Nth and Nmax in the formula, sigmoid logistic function was employed for 
B concentration data, Db(t) obtained by dynamic PETtechnique, where, A, a and t0 are constants. From the application of sigmoid function to dynamic PET data, it is concluded that the Nth and Nmax for tissue and tumor are identified with the parameter constants in the sigmoid function in tion as: th b at 0 and max N = D t = N = x.
Itami, Toshio*; Saito, Junichi; Ara, Kuniaki
Metals, 5(3), p.1212 - 1240, 2015/09
Times Cited Count：2 Percentile：3.38(Materials Science, Multidisciplinary)A new kind of suspension liquid was developed by dispersing Ti nanoparticles (10 nm) in liquid Na, which was then determined by TEM (transmission electron microscopy) analysis. The volume fraction was estimated to be 0.0088 from the analyzed Ti concentration (2 at.%) and the densities of Ti and Na. This suspension liquid, Liquid Sodium containing nanoparticles of titanium (LSnanop), shows, despite only a small addition of Ti nanoparticles, many striking features, namely a negative deviation of 3.9% from the ideal solution for the atomic volume, an increase of 17% in surface tension, a decrease of 11% for the reaction heat to water, and the suppression of chemical reactivity to water and oxygen. The decrease in reaction heat to water seems to be derived from the existence of excess cohesive energy of LSnanop. The excess cohesive energy was discussed based on simple theoretical analyses, with particular emphasis on the screening effect. The suppression of reactivity is discussed with the relation to the decrease of heat of reaction to water or the excess cohesive energy, surface tension, the action as a plug of Ti oxide, negative adsorption on the surface of LSnanop, and percolation.
Ishiyama, Shintaro; Imahori, Yoshio*; Itami, Jun*; Koivunoro, H.*
Journal of Cancer Therapy, 6(8), p.759 - 766, 2015/08
From the concentration of 10BPA drug was intravenously injected into the tumor and normal cells of brain tumor patients measured by dynamic PET method, the CBE factor for the BNCT treatment can be calculated by using ISHIYAMA-IMAHORI model.
Yoshida, Masafumi; Tanabe, Tetsuo*; Adachi, Ayumu*; Hayashi, Takao; Nakano, Tomohide; Fukumoto, Masakatsu; Yagyu, Junichi; Miyo, Yasuhiko; Masaki, Kei; Itami, Kiyoshi
Journal of Nuclear Materials, 438, p.S1261 - S1265, 2013/07
Times Cited Count：6 Percentile：42.36(Materials Science, Multidisciplinary)Fuel retention rates and carbon re-deposition rates in the plasma shadowed areas in JT-60U were measured. Distributions of the fuel retention as well as the carbon re-deposition in the whole in-vessel of a large tokamak were clarified for the first time in the world. The fuel retention in the plasma shadowed areas was about two times larger than that in the carbon re-deposited layers on the plasma facing surface, although the amount of the carbon re-deposited on the plasma shadowed areas were about a half of that on the plasma facing surface, because of relatively lower temperature in the shadow areas causing higher hydrogen saturation concentration in the carbon re-deposited layers. The total fuel retention rate in JT-60U, including previously measured for all plasma facing areas, was evaluated to be 1.3
10
H+Ds
, which was lower than that in other devices, due to probably to higher temperature operation in JT-60U.
Yoshida, Masafumi; Tanabe, Tetsuo*; Hayashi, Takao; Nakano, Tomohide; Fukumoto, Masakatsu; Yagyu, Junichi; Miyo, Yasuhiko; Masaki, Kei; Itami, Kiyoshi
Fusion Science and Technology, 63(1T), p.367 - 370, 2013/05
Times Cited Count：0 Percentile：0.00(Nuclear Science & Technology)In this study, the retentions of hydrogen isotopes (H and D) in the gaps in JT-60U are clarified. Carbon tiles used in 1992-2004 were poloidally and toroidally taken out from outboard first wall in JT-60U to measure the retentions. The H and D retentions in the samples were measured by thermal desorption spectrometry (TDS). The H+D retention in the top side was higher than that of the bottom side, which might be due to thicker re-deposited carbon layers on the surface of the top side. The retentions in the surface of the side surfaces were slightly lower than that in the plasma facing surface where the retention was saturated to be 3-4e22 atoms/m
. The retention rate was evaluated to be 3e17 H+D atoms/m/s from the measured retentions in two different discharge times by assuming the retention to increase linearly with the discharge time.
Saito, Junichi; Itami, Toshio; Ara, Kuniaki
Journal of Nanoparticle Research, 14(12), p.1298_1 - 1298_17, 2012/12
Times Cited Count：4 Percentile：19.26(Chemistry, Multidisciplinary)Tojo, Hiroshi; Ejiri, Akira*; Hiratsuka, Junichi*; Yamaguchi, Takashi*; Takase, Yuichi*; Itami, Kiyoshi; Hatae, Takaki
Journal of Instrumentation (Internet), 7(4), p.P04005_1 - P04005_11, 2012/04
Times Cited Count：3 Percentile：16.82(Instruments & Instrumentation)Tojo, Hiroshi; Ejiri, Akira*; Hiratsuka, Junichi*; Yamaguchi, Takashi*; Takase, Yuichi*; Itami, Kiyoshi; Hatae, Takaki
Review of Scientific Instruments, 83(2), p.023507_1 - 023507_4, 2012/02
Times Cited Count：11 Percentile：45.67(Instruments & Instrumentation)
8 and 14 keVYanagibayashi, Jun*; Nakano, Tomohide; Iwamae, Atsushi; Kubo, Hirotaka; Hasuo, Masahiro*; Itami, Kiyoshi
Journal of Physics B; Atomic, Molecular and Optical Physics, 43(14), p.144013_1 - 144013_6, 2010/07
Times Cited Count：26 Percentile：73.17(Optics)We observe the vacuum ultraviolet spectra of highly charged tungsten ions in plasmas at electron temperatures of 8 keV and 14 keV. The observed emission lines in a wavelength range of 2.6 
3.2 nm for the plasma at 8 keV are identified to be the 
transitions of 
. The observed emission lines at 2.0 nm and 2.3 nm at 14 keV are identified to be the 
transitions of 
and 
transitions of 
, respectively.
Matsuda, Norihiro; Nakashima, Hiroshi; Kasugai, Yoshimi; Sasamoto, Nobuo*; Kinno, Masaharu*; Kitami, Takayuki; Ichimura, Takahito; Hori, Junichi*; Ochiai, Kentaro; Nishitani, Takeo
Journal of Nuclear Science and Technology, 41(Suppl.4), p.74 - 77, 2004/03
In high power proton accelerator facilities, concrete shield can be highly activated, which makes maintenance work quite difficult. So, a low-activationized concrete (limestone concrete) is to be partially adopted as a concrete shield for Japan Proton Accelerator Research Complex (J-PARC) aiming at reducing 
-ray exposure dose during maintenance period. A new quantity, 
Na-equivalent, was introduced as a criterion to assure effectiveness of the low-activationized concrete. In order of its verification, powdered low-activationized concrete and ordinary one were irradiated using FNS at JAERI. The measurements were analyzed by a shielding design code system being used for J-PARC, showing that the calculations reproduce the measured induced activity within a factor of 2. Furthermore, by using the same code system, -ray exposure dose was calculated for the configuration of J-PARC to find out that -ray exposure dose by the low-activationized concrete was about 10 times lower than that by the ordinary concrete in a period of less than a few days after operation.
D
) in JT-60UNakano, Tomohide; Higashijima, Satoru; Kubo, Hirotaka; Yagyu, Junichi; Arai, Takashi; Asakura, Nobuyuki; Itami, Kiyoshi
Journal of Nuclear Materials, 313-316(1-3), p.149 - 152, 2003/03
Times Cited Count：30 Percentile：85.79(Materials Science, Multidisciplinary)In JT-60U, boronization using hydride-decaborane (BD) was performed to reduce oxygen impurity and particle recycling. A problem of the boronization was that hydrogen originating from hydride-decaborane diluted core deuterium plasmas. In order to minimize the number of conditioning tokamak discharges, boronization using deuterated-decaborane (BD) has been introduced recently. In order to investigate durability of the boronization effects, discharges with an identical condition were repeated. Boronization using 20 g of deuterated-decaborane could reduce a core oxygen content from 1.9% to only 1.3% in L-mode discharges with a neutral beam heating power of 4 MW. Boronization using 70 g of deuterated-decaborane reduced the core oxygen content from 2.2% to 0.5%. After the boronization using 70 g of deuterated-decaborane ( thickness of the Boron layer 135 nm ), the core oxygen content increased gradually from 0.5% to 1% in 400 shots.
Sumita, Junya; Sawa, Kazuhiro; Mogi, Haruyoshi; ; Kitami, Takayuki; Akutsu, Yoichi; ; ;
JAERI-Research 99-054, p.41 - 0, 1999/09
JAERI-Research-99-054.pdf:1.19MB
no abstracts in English
Nishitani, Takeo; Takeuchi, Hiroshi; Barnes, C. W.*; Iguchi, Tetsuo*; Nagashima, Akira; Kondoh, Takashi; Sakasai, Akira; Itami, Kiyoshi; Tobita, Kenji; Nagashima, Keisuke; et al.
JAERI-M 91-176, 23 Pages, 1991/10
no abstracts in English
Itami, Toshio; Ara, Kuniaki; Saito, Junichi; Nishimura, Masahiro
no journal, ,
no abstracts in English
Yanagibayashi, Jun; Nakano, Tomohide; Hasuo, Masahiro*; Iwamae, Atsushi; Kubo, Hirotaka; Itami, Kiyoshi
no journal, ,
Tungsten is one of the candidates for the divertor material of ITER because of its low retention and low hydrogen inventory. However, it is a problem that tungsten ions accumulated in a core plasma emit intense radiation and cool the plasma. For preparation of investigating the mechanism of the tungsten ion accumulation, Vaccum Ultra Violet (VUV) lines emitted from tungsten ions are identified. A VUV spectrum from a JT-60U plasma (
keV) is observed with a flat-field grazing-incidence spectrometer. The observed spectrum is compared with a theoretical spectrum calculated with Flexible Atomic Code. It is found that the observed peaks around 3 nm are due to transitions between 
levels of W
(
), and that those around 5, 6 and 13 nm are due to transitions between 
levels of W (
). It is believed that the former lines are useful to diagnose the tungsten ion accumulation in a high-temperature (
10 keV) plasma of ITER.
Tojo, Hiroshi; Hatae, Takaki; Sakuma, Takeshi; Hamano, Takashi; Itami, Kiyoshi; Ejiri, Akira*; Hiratsuka, Junichi*; Yamaguchi, Takashi*; Takase, Yuichi*
no journal, ,
no abstracts in English
Sato, Junya; Suzuki, Shinji*; Kato, Jun; Sakakibara, Tetsuro; Nakazawa, Osamu; Meguro, Yoshihiro; Ueda, Hiroshi*; Kurosaki, Fumio*; Yoneyama, Takashi*; Matsukura, Minoru*; et al.
no journal, ,
no abstracts in English
Mori, Koichi*; Komori, Hideyuki*; Kitami, Katsunobu*; Sato, Junya; Nakazawa, Osamu; Meguro, Yoshihiro; Ueda, Hiroshi*; Kurosaki, Fumio*; Matsukura, Minoru*; Mimura, Hitoshi*
no journal, ,
no abstracts in English
Itami, Toshio; Ara, Kuniaki; Saito, Junichi
no journal, ,
no abstracts in English
Tojo, Hiroshi; Ejiri, Akira*; Hiratsuka, Junichi*; Yamaguchi, Takashi*; Takase, Yuichi*; Itami, Kiyoshi
no journal, ,
Saito, Junichi; Itami, Toshio; Nagai, Keiichi; Ara, Kuniaki
no journal, ,
no abstracts in English
