Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Shimojo, Kojiro; Fujiwara, Iori*; Oshima, Tatsuya*; Yokoyama, Keiichi; Yaita, Tsuyoshi
Analytical Sciences, 38(7), p.1003 - 1006, 2022/07
Times Cited Count：0 Percentile：0(Chemistry, Analytical)Liquid-liquid extraction of lanthanide (Ln) ions was investigated using 
-dioctylthiodiglycolamic acid (DOTDGAA), which is a sulfur donor ligand with an amide group and a carboxyl group connected by a thioether chain. The extraction performance and selectivity of DOTDGAA for Ln ions were compared with those of -dioctyldiglycolamic acid (DODGAA), which is also an oxygen donor ligand with a similar chemical structure, to assess the effect of the soft/hard donor atom on Ln separation. DOTDGAA quantitatively extracted all Ln ions while being selective toward light and middle Ln ions, in contrast to the selectivity of DODGAA for heavier Ln ions. Slope analysis demonstrated that the Ln
transfer using DOTDGAA proceeded through a proton-exchange reaction, forming a 1:3 complex, Ln(DOTDGAA)
. The back-extraction of Ln ions from the extracting phase was successfully achieved under acidic conditions.
Akagi, Hiroshi; Kasajima, Tatsuya*; Kumada, Takayuki; Itakura, Ryuji; Yokoyama, Atsushi; Hasegawa, Hirokazu*; Oshima, Yasuhiro*
Physical Review A, 91(6), p.063416_1 - 063416_7, 2015/06
Times Cited Count：7 Percentile：39.53(Optics)We propose a strategy of isotope-selective ionization for a binary mixture of isotopologues of homonuclear diatomic molecules, utilizing field-free alignment with a train of femtosecond laser pulses. Field-free alignment can be achieved simultaneously for two isotopologues consisting of two atoms with the same atomic mass number 
or 
, utilizing a pulse train with their time interval of T
= T() = T(), where T() and T() are the rotational revival times of the isotopologues. We demonstrate experimentally that a train of four alignment pulses with their interval of T ( = 14, = 15) creates transiently aligned 
N
and anti-aligned 
N just before T/2 after the last pulse, and vice versa just after T/2. Highly isotope-selective N ionization is achieved at these timings with another femtosecond laser pulse, which induces the non-resonant multiphoton ionization with the cross section remarkably depending on the angle between the molecular axis and the laser electric field direction. The ion yield ratio I(N
)/I(N) ranges from 0.49 to 2.00, which is wider than the range obtained with single alignment pulse.
SiTabata, Chihiro*; Inami, Toshiya; Michimura, Shinji*; Yokoyama, Makoto*; Hidaka, Hiroyuki*; Yanagisawa, Tatsuya*; Amitsuka, Hiroshi*
Philosophical Magazine, 94(32-33), p.3691 - 3701, 2014/00
Times Cited Count：15 Percentile：59(Materials Science, Multidisciplinary)Sato, Toshinori; Tanno, Takeo; Sanada, Hiroyuki; Yokoyama, Tatsuya*; Shimoyama, Masahiro*
Heisei-25 Nendo (2013 Nen) Shigen, Sozai Gakkai Shuki Taikai Koenshu, p.257 - 258, 2013/09
Japan Atomic Energy Agency is operating underground research laboratory projects in order to establish a firm scientific basis for safe geological disposal of HLW. One of these is the Mizunami Underground Research Laboratory (MIU) project focused on crystalline rock. In situ stress measurement by Compact Conical-ended Borehole Overcoring (CCBO) are conducted to understand in situ stress state at 300 m depth.
Tanno, Takeo; Sato, Toshinori; Sanada, Hiroyuki; Hikima, Ryoichi*; Yokoyama, Tatsuya*; Shimoyama, Masahiro*
Heisei-25 Nendo (2013 Nen) Shigen, Sozai Gakkai Shuki Taikai Koenshu, p.255 - 256, 2013/09
rock stresses were measured by Compact Conical-ended Borehole Overcoring (CCBO) technique in the 300m depth gallery at the Mizunami Underground Research Laboratory and the measurement results were evaluated using a conventional method and a new test of strain sensitivity method. To compare the 
rock stress evaluated by both methods, the new test of strain sensitivity method resulted in more accurate evaluation than the conventional method, because of its improved stress deviations.
7 reconstructionAsaoka, Hidehito; Yamazaki, Tatsuya; Yokoyama, Yuta; Yamaguchi, Kenji
Journal of Crystal Growth, 378, p.37 - 40, 2013/09
Times Cited Count：3 Percentile：32.2(Crystallography)We have focused on stress measurements of the reconstructed Si(111) 77 and the H-terminated Si(111) 11 surfaces. In order to obtain information on both the surface stress and the surface structure simultaneously, we have combined the surface-curvature and the reflection-high-electron-energy-diffraction instrumentations in an identical ultrahigh vacuum system. At the beginning of Ge wetting layer growth on H-terminated Si(111), the stress gradient drastically changes accompanied by change in the surface structure resulting from the H desorption. Comparison of the surface stress behaviors between Ge wetting layer growth on the H-terminated Si(111) 11 and the Si(111) 77 surfaces reveals that the Si(111) 11 surface releases 1.6 N/m (=J/m
), or (1.3 eV/(11 unit cell)), of the surface energy from the strong tensile Si(111) 77 reconstruction.
Yokoyama, Yuta; Yamazaki, Tatsuya; Asaoka, Hidehito
Journal of Crystal Growth, 378, p.230 - 232, 2013/09
Times Cited Count：2 Percentile：23.87(Crystallography)The initial processes of Ge nano cluster formation on Si(110)-162 reconstructed structure were investigated via scanning tunneling microscopy. For a small amount of Ge deposited on Si(110)-162 single-domain structure at room temperature, the surface structure did not change significantly. After direct current heating at 973 K for 20 min, the striped structure almost broken and disordered-like structure was formed on the terrace. With increasing the annealing time, the surface structure changed from disordered-like structure to the 162 double-domain structure and pyramidal nano clusters were formed at the domain boundary. These results suggest that the surface stress was induced by Ge nano cluster formation and the double-domain structure was formed in order to relax the stress.
Akagi, Hiroshi; Kasajima, Tatsuya; Kumada, Takayuki; Itakura, Ryuji; Yokoyama, Atsushi; Hasegawa, Hirokazu*; Oshima, Yasuhiro*
Applied Physics B, 109(1), p.75 - 80, 2012/10
Times Cited Count：16 Percentile：61.87(Optics)We demonstrate a laser nitrogen isotope separation, which is based on field-free alignment and angular dependent ionization of N and N isotopomers. A linearly-polarized short laser pulse (
795 nm, 
60 fs) creates rotational wave packets in the isotopomers, which periodically revive with different revival times as a result of different moments of inertia. Another linearly-polarized short laser pulse (795 nm, 60 fs) ionizes one of the isotopomers selectively as a result of their different angular distributions. In the present experiments, the ion yield ratio 
[= 
(N)/(N)] can be changed in the range from 0.85 to 1.22, depending on the time delay between the two laser pulses.
Matsuoka, Leo; Kasajima, Tatsuya; Hashimoto, Masashi; Yokoyama, Keiichi
Journal of the Korean Physical Society, 59(4), p.2897 - 2900, 2011/10
Times Cited Count：12 Percentile：60.77(Physics, Multidisciplinary)Matsuoka, Leo; Kasajima, Tatsuya; Hashimoto, Masashi; Yokoyama, Keiichi
arXiv.org (Internet), 5 Pages, 2011/04
Sato, Shoichi*; Ichimura, Makoto*; Yamaguchi, Yusuke*; Katano, Makoto*; Imai, Yasutaka*; Murakami, Tatsuya*; Miyake, Yuichiro*; Yokoyama, Takuro*; Moriyama, Shinichi; Kobayashi, Takayuki; et al.
Plasma and Fusion Research (Internet), 5, p.S2067_1 - S2067_4, 2010/12
Ion cyclotron emissions (ICEs) due to deuterium-deuterium fusion-product (FP) ions on JT-60U are studied. ICE due to H-ions is identified from the difference of the toroidal wave number of 2nd ICE(D). The parameter dependence for the appearance of ICE(H) is investigated from the experimental conditions and also is studied by using "Escape Particle Orbit analysis Code (EPOC)".
Kasajima, Tatsuya; Yokoyama, Keiichi; Matsuoka, Leo; Yokoyama, Atsushi
Chemical Physics Letters, 485(1-3), p.45 - 48, 2010/01
Times Cited Count：1 Percentile：3.08(Chemistry, Physical)Yokoyama, Keiichi; Matsuoka, Leo; Kasajima, Tatsuya; Tsubouchi, Masaaki; Yokoyama, Atsushi
Proceedings of 5th Asian Symposium on Intense Laser Science (ASILS-5), p.113 - 119, 2009/05
The current status of the fundamental research for the quantum control conducted at Kansai Photon Science Institute are reported. In particular, the experimental studies on vibrational control of diatomic molecules, the nitrogen molecules and the iodine molecules, and the theoretical study on the rotational control of the diatomic molecule, the cesium iodide molecule (CsI), are introduced. For the study of vibrational control of N, the vibration selective excitation with extremely broadband white light pulses is demonstrated by tuning the time interval of a linearly chirped white light pulse pair. For the study of vibrational control of I, the direction control of stimulated impulsive Raman transition is demonstrated by changing the sign of the chirp rate. For the study of rotational control of CsI, the isotope-selective population distribution transfer is demonstrated numerically using frequency comb in the terahertz-wave region.
Suzuki, Satoshi; Ito, Tatsuya*; Nobuta, Yuji*; Yamauchi, Yuji*; Hino, Tomoaki*; Ezato, Koichiro; Yokoyama, Kenji; Akiba, Masato
no journal, ,
A reduced activation ferritic-maternstic steel, F82H, is one of candidate structural materials for the first wall of fusion machines. For F82H, retention and desorption behavior of F82H has not been clarified though such behavior is considered to be significant from the plasma density control and safety points of view. In this study, F82H samples were irradiated by hydrogen ion in JAEA. In addition, these samples with surface defects were also irradiated by deuterium ion to investigate the retention and the desorption behavior based on its surface defects. As a result, while the amount of the deuterium retention has not been changed at a holding temperature below 550 K, it is significantly decreased at a holding temperature over 770 K.
Kasajima, Tatsuya; Yokoyama, Keiichi; Matsuoka, Leo; Yokoyama, Atsushi
no journal, ,
no abstracts in English
in the B 
(0
) stateMatsuoka, Leo; Yokoyama, Keiichi; Kasajima, Tatsuya; Yokoyama, Atsushi
no journal, ,
no abstracts in English
Sato, Shoichi*; Ichimura, Makoto*; Yamaguchi, Yusuke*; Katano, Makoto*; Imai, Yasutaka*; Murakami, Tatsuya*; Miyake, Yuichiro*; Yokoyama, Takuro*; Moriyama, Shinichi; Kobayashi, Takayuki; et al.
no journal, ,
Ion cyclotron emissions (ICEs) due to deuterium-deuterium fusion-product (FP) ions on JT-60U are studied. ICE due to H-ions is identified from the difference of the toroidal wave number of 2nd ICE(D). The parameter dependence for the appearance of ICE(H) is investigated from the experimental conditions and also is studied by using "Escape Particle Orbit analysis Code (EPOC)".
Kasajima, Tatsuya; Tsubouchi, Masaaki; Matsuoka, Leo; Yokoyama, Keiichi; Yokoyama, Atsushi
no journal, ,
no abstracts in English
Yokoyama, Keiichi; Matsuoka, Leo; Akagi, Hiroshi; Kasajima, Tatsuya; Tsubouchi, Masaaki
no journal, ,
Pure rotational transition shows evenly spaced line spectra, the rotational comb, when the molecule is diatomic and has a closed-shell electronic structure. Let us consider irradiating an optical frequency comb tuned to the rotational comb. We studied numerically the dynamics of the molecular rotation in such a irradiation. As a result, the dynamics was found to obey the diffusion equation within the quantum mechanics. Also, we found that an isotope-selective excitation based on this scheme is a novel example of coherent control effective even at high temperature.
Kasajima, Tatsuya; Tsubouchi, Masaaki; Yokoyama, Keiichi
no journal, ,
no abstracts in English
