Refine your search:     
Report No.
 - 
Search Results: Records 1-16 displayed on this page of 16
  • 1

Presentation/Publication Type

Initialising ...

Refine

Journal/Book Title

Initialising ...

Meeting title

Initialising ...

First Author

Initialising ...

Keyword

Initialising ...

Language

Initialising ...

Publication Year

Initialising ...

Held year of conference

Initialising ...

Save select records

Journal Articles

Data of heavy elements for light sources in EUV and XUV and for other applications

Koike, Fumihiro*; Funaba, Hisamichi*; Goto, Motoshi*; Kato, Daiji*; Kato, Takako*; Morita, Shigeru*; Murakami, Izumi*; Sakaue, Hiroyuki*; Sudo, Shigeru*; Suzuki, Chihiro*; et al.

AIP Conference Proceedings 1545, p.202 - 211, 2013/07

 Times Cited Count:3 Percentile:81.12

Atomic ionic states and transition properties of elements with atomic numbers Z ranging from 50 to 80 are discussed as these are important to the understanding of plasmas containing such heavy elements. As such, data productions and the current status of theoretical calculations in this field are discussed. Further, recent spectroscopic measurements and respective theoretical analyses for W, Gd, and Nd are provided.

Journal Articles

A Study of tungsten spectra using Large Helical Device and Compact Electron Beam Ion Trap in NIFS

Morita, Shigeru*; Dong, C. F.*; Goto, Motoshi*; Kato, Daiji*; Murakami, Izumi*; Sakaue, Hiroyuki*; Hasuo, Masahiro*; Koike, Fumihiro*; Nakamura, Nobuyuki*; Oishi, Tetsutaro*; et al.

AIP Conference Proceedings 1545, p.143 - 152, 2013/07

 Times Cited Count:26 Percentile:99.38

Tungsten spectra have been observed from Large Helical Device (LHD) and Compact electron Beam Ion Trap (CoBIT) in wavelength ranges of visible to EUV. The tungsten spectra from LHD are well analyzed based on the knowledge from CoBIT tungsten spectra. The C-R model code has been developed to explain the UTA spectra in details. Radial profiles of EUV spectra from highly ionized tungsten ions have been measured and analyzed by impurity transport simulation code with ADPAK atomic database code to examine the ionization balance determined by ionization and recombination rate coefficients. The ablation cloud of the impurity pellet is directly measured with visible spectroscopy.

Journal Articles

Alignment creation and deviation from statistical population distribution in hydrogen $$n$$=3 levels observed on MSE spectra of LHD plasma

Iwamae, Atsushi; Sakaue, Atsushi*; Atake, Makoto*; Sawada, Keiji*; Goto, Motoshi*; Morita, Shigeru*

Plasma Physics and Controlled Fusion, 51(11), p.115004_1 - 115004_15, 2009/11

 Times Cited Count:6 Percentile:26.14(Physics, Fluids & Plasmas)

Journal Articles

Extended steady-state and high-beta regimes of net-current free heliotron plasmas in the Large Helical Device

Motojima, Osamu*; Yamada, Hiroshi*; Komori, Akio*; Oyabu, Nobuyoshi*; Muto, Takashi*; Kaneko, Osamu*; Kawahata, Kazuo*; Mito, Toshiyuki*; Ida, Katsumi*; Imagawa, Shinsaku*; et al.

Nuclear Fusion, 47(10), p.S668 - S676, 2007/10

 Times Cited Count:34 Percentile:76.72(Physics, Fluids & Plasmas)

The performance of net-current free heliotron plasmas has been developed by findings of innovative operational scenarios in conjunction with an upgrade of the heating power and the pumping/fuelling capability in the Large Helical Device (LHD). Consequently, the operational regime has been extended, in particular, with regard to high density, long pulse length and high beta. Diversified studies in LHD have elucidated the advantages of net-current free heliotron plasmas. In particular, an internal diffusion barrier (IDB) by a combination of efficient pumping of the local island divertor function and core fuelling by pellet injection has realized a super dense core as high as 5$$times$$10$$^{20}$$ m$$^{-3}$$, which stimulates an attractive super dense core reactor. Achievements of a volume averaged beta of 4.5% and a discharge duration of 54 min with a total input energy of 1.6 GJ (490 kW on average) are also highlighted. The progress of LHD experiments in these two years is overviewed by highlighting IDB, high-beta and long pulse.

Journal Articles

Extended steady-state and high-beta regimes of net-current free heliotron plasmas in the large helical device

Motojima, Osamu*; Yamada, Hiroshi*; Komori, Akio*; Oyabu, Nobuyoshi*; Kaneko, Osamu*; Kawahata, Kazuo*; Mito, Toshiyuki*; Muto, Takashi*; Ida, Katsumi*; Imagawa, Shinsaku*; et al.

Proceedings of 21st IAEA Fusion Energy Conference (FEC 2006) (CD-ROM), 12 Pages, 2007/03

The performance of net-current free Heliotron plasmas has been developed by findings of innovative operational scenarios in conjunction with an upgrade of the heating power and the pumping/fueling capability in the Large Helical Device (LHD). Consequently, the operational regime has been extended, in particular, with regard to high density, long pulse length and high beta. Diversified studies in LHD have elucidated the advantages of net-current free heliotron plasmas. In particular, an Internal Diffusion Barrier (IDB) by combination of efficient pumping of the local island divertor function and core fueling by pellet injection has realized a super dense core as high as 5$$times$$10$$^{20}$$m$$^{-3}$$, which stimulates an attractive super dense core reactor. Achievements of a volume averaged beta of 4.5 % and a discharge duration of 54-min. with a total input energy of 1.6 GJ (490 kW in average) are also highlighted. The progress of LHD experiments in these two years is overviewed with highlighting IDB, high $$beta$$ and long pulse.

Journal Articles

Spatial structure and dynamics of ELM crash

Oyama, Naoyuki; Morita, Shigeru*

Purazuma, Kaku Yugo Gakkai-Shi, 82(9), p.575 - 581, 2006/09

no abstracts in English

Journal Articles

Radiation loss by impurities measured from the large helical device

Kato, Takako*; Murakami, Izumi*; Goto, Motoshi*; Morita, Shigeru*; Ida, Katsumi*; Peterson, B. J.*; Funaba, Hisamichi*; Nakano, Tomohide

Journal of Plasma and Fusion Research SERIES, Vol.7, p.1 - 4, 2006/00

We analyzed impurity VUV spectral emission quantitatively. Electron temperature is derived from the intensity ratio of CIII line intensities. Radiation loss sources are identified using spectroscopy and bolometer in the case of radiation collapse caused by neon gas puffing. Time dependent radiation loss of impurity ions are derived from line intensities of impurities.

Journal Articles

Development of SiC/SiC composite from precursor polymer by radiation application

Sugimoto, Masaki; Morita, Yosuke; Tanaka, Shigeru; Seguchi, Tadao; Ito, Masayoshi*; Okamura, Kiyohito*

IAEA-SM-365/7, p.35 - 40, 2003/09

no abstracts in English

Journal Articles

Fine SiC fiber synthesized from organosilicon polymers; Relationship between spinning temperature and melt viscosity of precursor polymers

Idesaki, Akira; Narisawa, Masaki*; Okamura, Kiyohito*; Sugimoto, Masaki; Tanaka, Shigeru; Morita, Yosuke; Seguchi, Tadao; Ito, Masayoshi*

Journal of Materials Science, 36(23), p.5565 - 5569, 2001/12

 Times Cited Count:36 Percentile:77.69(Materials Science, Multidisciplinary)

A very fine silicon carbide (SiC) fiber with diameter of 6 $$mu$$ m, about a half of that of a commercially available SiC fiber, was synthesized from a polymer blend of polycarbosilane (PCS) and polyvinylsilane (PVS). The fine SiC fiber was obtained by optimizing the composition and the spinning temperature of PCS-PVS polymer blends. In order to determine these optimum conditions, the relationship between temperature and melt viscosities of the polymer blends was investigated. As a result, it was found that the optimum spinning temperature range was within a temperature range where the melt viscosity is 5-10Pa$$cdot$$s. Moreover, by blending PVS with PCS, the spinning temperature of the polymer blends was lowered, the spinnability of polymer system was improved, and finer polymer fiber was obtained compared with PCS. The optimum content of PVS in the polymer blend was 15-20wt%.

Journal Articles

Fine silicon carbide fiber synthesized from a silicon-based polymer blend using radiation curing

Idesaki, Akira; Sugimoto, Masaki; Tanaka, Shigeru; Morita, Yosuke; Narisawa, Masaki*; Okamura, Kiyohito*; Ito, Masayoshi*

High Temperature Ceramic Matrix Composites, p.35 - 40, 2001/00

Silicon carbide (SiC) fiber, which is one of the likeliest candidates as a reinforcement fiber of ceramic matrix composites (CMCs), is synthesized from polycarbosilane (PCS). The diameter of thus SiC fibers is 10-15 $$mu$$m. In order to fabricate CMCs with 3-dimensional complex shapes, it is important to develop a SiC fiber with diameter of less than 10 $$mu$$m, flexibility, and high strength. In order to improve the spinnability of precursor polymer, we have blended polyvinylsilane (PVS), which is a liquid polymer at room temperature, to PCS as a spinning additive. According to relationship between temperature and melt viscosity of the polymer blend, it was found that the polymer can be melt-spun at about 490K, 110K lower than PCS (about 600K), and that the spinnability of the polymer is improved by blending PVS. Fine polymer fiber was obtained from the polymer blend, and finally, very fine SiC fiber with the average diameter of 6 $$mu$$m was synthesized from the PCS-PVS polymer blend.

Journal Articles

Development of a partitioning method for the management of high-level liquid waste

Kubota, Masumitsu; Dojiri, Shigeru; Yamaguchi, Isoo; Morita, Yasuji; ; *; *

Proc. of the 1989 Joint Int. Waste Management Conf., Vol. 2, p.537 - 542, 1989/00

no abstracts in English

Journal Articles

Dosimetric characteristics of alanine dosimeter AMINOGRAY and its application

Kashiwazaki, Shigeru*; *; *; *; Kojima, Takuji; Tanaka, Ryuichi; Morita, Yosuke

EIM-88-124, p.61 - 67, 1988/12

no abstracts in English

Journal Articles

AMINOGRAY, Alanine dosimeter

Kojima, Takuji; Morita, Yosuke; Tanaka, Ryuichi; Kashiwazaki, Shigeru*; *

Hitachi Cable Review, 0(7), p.85 - 88, 1988/08

no abstracts in English

Journal Articles

Alanine dosimeter; Aminogray

Kojima, Takuji; Morita, Yosuke; Tanaka, Ryuichi; Kashiwazaki, Shigeru*; *

Hitachi Densen, 0(7), p.79 - 82, 1988/00

no abstracts in English

Oral presentation

Study of nLTE kinetic model of high-z ions for laser plasma produced (LPP) EUV sources to fusion plasmas

Sasaki, Akira; Murakami, Izumi*; Kato, Daiji*; Morita, Shigeru*

no journal, , 

The non-local thermodynamic equilibrium (nLTE) atomic kinetics in high-Z plasmas is investigated for Ag, Sn through W, which are used for X-ray lasers, EUV sources and fusion devices. We develop the atomic model based on nl configuration averaged levels structure, with atomic energy levels, radiative rates and autoionization rates calculated using the HULLAC code. The dielectronic recombination processes are included into the model by including autoionizing levels explicitly. We investigate the mean charge and radiative power loss with respect to the size of the model; by defining the groups of the levels, which consist of core a configuration and one excited electron, and by performing calculations increasing the number of groups. It is found that as a general trend, the mean charge decreases and the radiative power loss increases, until convergence is obtained when sufficiently large number of dielectronic recombination channels is included. The model is validated at code comparison workshops and also comparison with spectroscopic measurements, which are carried out using magnetic fusion devices.

Oral presentation

Hybrid process combining solvent extraction and low pressure loss extraction chromatography for a reasonable MA recovery, 6; Evaluation of adsorption and elution behavior of adsorbent for MA/Ln separation

Yoshida, Masaaki*; Nemoto, Shuhei*; Nagase, Midori*; Arai, Tsuyoshi*; Emori, Tatsuya; Morita, Keisuke; Ban, Yasutoshi; Watanabe, So; Sano, Yuichi; Kunii, Shigeru*

no journal, , 

In this study, we investigated the adsorption characteristics of simulated nuclides of adsorbents carrying various NTA amide extracts. From the results of this test, It has become clear that HONTA-impregnated adsorbent showed a high adsorption distribution coefficient with respect to Ln (III) at a nitric acid concentration of 10$$^{-3}$$ - 10$$^{-2}$$ M. It has also revealed that all elements quickly reached adsorption equilibrium. In addition, the elution of the extractant and Sty / DVB was not occurred from the results of the extractant elution test from the impregnated adsorbent. We discuss the applicability of the extraction chromatography method using various NTA adsorbents.

16 (Records 1-16 displayed on this page)
  • 1