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Observation of Magnetic Dipole Forbidden Transitions in LHD and Its Application to Burning Plasma Diagnostics

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Plasma Science and Technology 2010年第3期12卷 341-347页

作者： Shigeru MORITA motoshi goto Ryuji KATAI Chunfeng DONG Hiroyuki SAKAUE Hangyu ZHOU National Institute for Fusion Science Institute of Laser Engineering Osaka University Graduate University for Advanced Studies

Magnetic dipole forbidden （M1） transition was studied in large helical device （LHD） and F-, Si- and Ti-like M1 transitions are successfully observed for highly ionized Ar, Kr, Mo and Xe ions. The wavelengths measured in visible range for the heavy elements, which are carefully determined with extremely small uncertainties of 0.02 - 0.05 A as a standard wavelength of usual electric dipole （El） plasma emissions, are compared with theoretical predictions. The result shows a good agreement with recent Hatree-Fock calculation including semi-empirical adjustment. The M1 intensity for the F-like ions is examined by analyzing the intensity ratio of M1 to El. Density dependence of the ratio is experimentally verified by comparing with collisional- radiative model calculation on level population. The M1/E1 line ratio for the F-like ions is applied to the α （He^2＋） particle diagnostics in ITER, in which a steady-state operation of burning plasmas based on D-T fusion reaction is expected with α particle heating. Unfortunately, the present estimation suggests a negative result for the α particle measurement because the ratio is largely enhanced by the collisional excitation with bulk ions due to high ion temperature of ITER of 10 keV as assumed and the resultant effect of the collisional excitation with α particles becomes less. Meanwhile, the M1 transition, in particular, Ti-like WLIII （W^52＋） transition （3627 A） emitted in visible range, is very useful for diagnostics of the impurity behavior and the core plasma parameters in ITER.

关键词： magnetic dipole transition, α particle ITER

Observation of Impurity Accumulation After Hydrogen Multi-Pellet Injection in Large Helical Device

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Plasma Science and Technology 2013年第3期15卷 230-234页

作者：董春凤 Shigeru MORITA motoshi goto 王二辉 Gen MOTOJIAMA Izumi MURAKAMI Ryuichi SAKAMOTO Norimasa YAMAMOTO National Institute for Fusion Science Department of Fusion Science Graduate University for Advanced Studies Center of Applied Superconductivity & Sustainable Energy Research Chubu University

Impurity accumulation is studied for neutral beam-heated discharges after hydrogen multi-pellet injection in Large Helical Device （LHD）. Iron density profiles are derived from radial profiles of EUV line emissions of FeXV-XXIV with the help of the collisional-radiative model. A peaked density profile of Fe2a＋ is simulated by using one-dimensional impurity transport code. The result indicates a large inward velocity of -6 m/s at the impurity accumulation phase. However, the discharge is not entirely affected by the impurity accumulation, since the concentration of iron impurity, estimated to be 3.3x10-5 to the electron density, is considerably small. On the other hand, a flat profile is observed for the carbon density of C6＋, which is derived from the Zeff profile, indicating a small inward velocity of -1 m/s. These results suggest atomic number dependence in the impurity accumulation of LHD, which is similar to the tokamak result.

关键词： impurity accumulation EUV spectrometer inward velocity

Improvement of Plasma Performance Using Carbon Pellet Injection in Large Helical Device

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Plasma Science and Technology 2011年第3期13卷 290-296页

作者： Shigeru MORITA motoshi goto Kenichi NAGAOKA Chunfeng DONG Hangyu ZHOU Zhengying CUI Yunbo DONC Xiang GAO TKatsumi IDA Katsunori IKED Osamu KANEKO Shiyao LIN Haruhisa NAKANO Masaki OSAKABE Ryuichi SAKAMOTO Yasuhiko TAKEIRI Ang TI Katsuyoshi TSUMORI Mikiro YOSHINUMA LHD experiment group National Institute for Fusion Science Toki 509-5292 Gifu Japan Graduate University for Advanced Studies Toki 509-5292 Gifu Japan Southwestern Institute of Physics Chengdu 610041 China Institute of Plasma Physics Chinese Academy of Sciences Hefei 230031 China

A cylindrical carbon pellet with a size of 1.2L x 1.2φ mm to 1.8L x 1.8φ mm and a velocity of 100 m/s to 300 m/s was injected into large helical device （LHD） for an efficient fueling based on its deeper deposition instead of hydrogen gas puffing and ice pellet injection. Electron density increment of Ane = 10^14 cm^-3 is successfully obtained by single carbon pellet injection without plasma collapse. Typical density and temperature of the ablation plasma of the carbon pellet, e.g., 6.5× 10^16 cm^-3 and 2.5 eV for CII, are examined respectively by spectroscopic method. A confinement improvement up to 50% compared to ISS-95 stellarator scaling is clearly observed in a relatively low-density regime of ne = 2 × 10^13 cm^-3 to 4×10^13 cm^-3, and high ion temperature Ti（0） of about 6 keV is also observed with an internal transport barrier at ne = 1.2 × 10^13 cm^-3. In particular, the improvement in the ion temperature largely exceeds that observed in hydrogen gas-puffed discharges, which typically ranges below 3 keV.

关键词： carbon pellet injection confinement improvement high ion temperature

Edge and Core Impurity Transport Study With Spectroscopic Instruments in LHD

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Plasma Science and Technology 2009年第4期11卷 402-408页

作者： Shigeru MORITA motoshi goto Masahiro KOBAYASHI Sadatsugu MUTO Malay Bikas CHOWDHURI 董春凤周航宇崔正英 Keisuke FUJII Akihiro FURUZAWA Masahiro HASUO AtsushiI WAMAE 揭银先 Mohammed KOUBITI Ikuya SAKURAI Yuzuru TAWARA 万宝年吴振伟 Naohiro YAMAGUCHI National Institute for Fusion Science Department of Fusion Science Graduate University for Advanced Studies Southwestern Institute of Physics Department of Engineering Physics Kyoto University EcoTopia Science Institute Nagoya University Institute of Plasma Physics Chinese Academy of Sciences PIIM University of Province Physics Laboratory Graduate School of Medicine and Pharmaceutical SciencesUniversity of Toyama

Impurity transport was investigated at both edge and core regions in large helical de- vice （LHD） with developed spectroscopic instruments which can measure one- and two-dimensional distributions of impurities. The edge impurity behavior was studied recently using four carbon resonant transitions in different ionization stages of CIII （977A）, CIV （1548A）, CV （40.3A） and CVI （33.7A）. When the line-averaged electron density, ne, is increased from 1 to 6 × 10^13 cm-3, the ratio of （CIII^CIV）/ne increases while the ratio of （CV＋CVI）/ne decreases. Here, CIII^CIV （CV＋CVI） expresses the sum of CIII （CV） and CIV （CVI） intensities. The CIII＋CIV indicates the carbon influx and the CV＋CVI indicates the emissions through the transport in the ergodic layer. The result thus gives experimental evidence on the impurity screening by the ergodic layer in LHD, which is also supported by a three-dimensional edge particle simulation. The core impu- rity behavior is also studied in high-density discharges （ne 〈 1 × 10^15 cm 3） with multi H2-pellets injection. It is found that the ratio of V/D （V： convection velocity, D： diffusion coefficient） decreases after pellet injection and Zeff profile shows a flat one at values of 1.1,-1.2. These results confirm no impurity accumulation occurs in high-density discharges. As a result, the iron density, rife, is analyzed to be 6 × 10^-7（=- nFe/ne） of which the amount can be negligible as radiation source even in such high-density discharges. One- and two-dimensional impurity distributions from space-resolved VUV and EUV spectrometers newly developed for further impurity transport study are also presented with their preliminary results.

关键词： impurity transport screening effect VUV spectroscopy

Spectroscopic Studies on Impurity Transport of Core and Edge Plasmas in LHD

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Plasma Science and Technology 2006年第1期8卷 55-60页

作者： Shigeru MORITA motoshi goto SadatsuguMUTO Ryuji KATAI Hisamichi YAMAZAKI Hideaki NOZATO AtsuslliI WAMAE Makoto ATAKE Takashi FUJIMOTO Atsushi SAKAUE Hiroaki NISHIMURA Ikuya SAKURAI Chiho MATSUMOTO Akihiro FURUZAWA Yuzuru TAWARA Mitsutoshi ARAMAKI Yuji OKUMURA Koichi SASAKI 龚先祖李建刚万宝年崔正英 National Institute for Fusion Science Toki 509-5292Japan Department of Fusion Science Graduate University for Advanced StudiesToki 509-5292Japan National Institute of Advanced Industrial Science and Technology Tsukuba 305-8563Japan Department of Engineering Physics Kyoto UniversityKyoto 606-8502Japan Institute of Laser Engineering Osaka UniversityOsaka 565-0871Japan Eco Topia Science Institute Nagoya UniversityNagoya 464-8603Japan Department of Electrical Engineering and Computer Science Nagoya UniversityNagoya 464-8603Japan Institute of Plasma Physics Chinese Academy of SciencesHefei 230031China Southwestern Institute of Physics Chengdu 610041China

Spectroscopic diagnostics have been extensively developed for studies of impurity and neutral particle transports at core and edge plasmas in LHD. Diagnostics of core plasmas are similar to a tokamak case, i.e., Zeff from visible bremsstrahlung, K-x-ray measurements from xray spectroscopy using Si（Li） detectors and a compact crystal spectrometer, and high-Z impurity diagnostics from VUV spectroscopy using a flat-field EUV spectrometer. A combination of impurity pellet injection and visible bremsstrahlung is an active tool for determination of the diffusion coeffici＇ent D and convective velocity V. Using this tool the spatial structures of D and V are obtained and discussed with a neoclassical effect. On the other hand, the spectroscopic method for edge diagnostics is considerably different from the tokamak case because of the existence of a thick ergodic layer in addition to the z-points necessarily included into the diagnostic chord view. In order to break this negative situation, Zeeman and polarization spectroscopy are adopted to LHD edge plasmas. As a result, 2-dimensional emission contours of HeI and Ha are successfully obtained. Laser absorption spectroscopy is tried to measure hydrogen neutrals directly. Radial profiles of edge impurities are also measured with a mirror-assembled 3 m VUV spectrometer. Recent results of and progress in LHD spectroscopy are briefly reviewed.

关键词： impurity transport plasma spectroscopy hydrogen neutral

Line identification of boron and nitrogen emissions in extreme-and vacuumultraviolet wavelength ranges in the impurity powder dropping experiments of the Large Helical Device and its application to spectroscopic diagnostics

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Plasma Science and Technology 2021年第8期23卷 6-17页

作者： Tetsutarou OISHI Naoko ASHIKAWA Federico NESPOLI Suguru MASUZAKI Mamoru SHOJI Eric P GILSON Robert LUNSFORD Shigeru MORITA motoshi goto Yasuko KAWAMOTO Chihiro SUZUKI Zhen SUN Alex NAGY David A GATES Tomohiro MORISAKI Department of Fusion Science The Graduate University for Advanced StudiesSOKENDAI322-6 Oroshi-choToki 509-5292GifuJapan Princeton Plasma Physics Laboratory 100 Stellarator RoadPrincetonNJ 08540United States of America National Institute for Fusion Science National Institutes of Natural Sciences322-6 Oroshi-choToki 509-5292GifuJapan

An impurity powder dropper was installed in the 21 st campaign of the Large Helical Device experiment(Oct.2019–Feb.2020)under a collaboration between the National Institute for Fusion Science and the Princeton Plasma Physics Laboratory for the purposes of real-time wall conditioning and edge plasma *** order to assess the effective injection of the impurity powders,spectroscopic diagnostics were applied to observe line emission from the injected ***,extreme-ultraviolet(EUV)and vacuum-ultraviolet(VUV)emission spectra were analyzed to summarize observable impurity lines with B and BN powder *** lines released from B and N ions were identified in the EUV wavelength range of 5–300Ameasured using two grazing incidence flat-field EUV spectrometers and in the VUV wavelength range of 300–2400Ameasured using three normal incidence 20 cm VUV ***–BV and NIII–NVII emission lines were identified in the discharges with the B and BN powder injection,*** B and N emission lines which have large intensities and are isolated from other lines were successfully identified as follows:BI(1825.89,1826.40)A(blended),BII 1362.46A,BIII(677.00,677.14,677.16)A(blended),BIV 60.31A,BV 48.59A,NIII(989.79,991.51,991.58)A(blended),NIV765.15A,NV(209.27,209.31)A(blended),NVI 1896.80A,and NVII *** of the line identifications to the advanced spectroscopic diagnostics were demonstrated,such as the vertical profile measurements for the BV and NVII lines using a space-resolved EUV spectrometer and the ion temperature measurement for the BII line using a normal incidence 3 m VUV spectrometer.

关键词： plasma spectroscopy extreme ultraviolet vacuum ultraviolet magnetically confined fusion impurity seeding wall conditioning

Adapted REDD plus Based on Local People’s Capabilities: A Case Study from Luang Prabang Province, Lao PDR

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Open Journal of Forestry 2017年第2期7卷 228-241页

作者： Marie Iwadare motoshi Hiratsuka Mitsubishi UFJ Research and Consulting Tokyo Japan Faculty of Human Sciences Waseda University Saitama Japan

The reducing emissions from deforestation and forest degradation (REDD plus) has been proposed as a key tool for reducing greenhouse gases (GHG) from deforestation and forest degradation in land use sector. The development of a REDD plus that considers national, sub-national, and/or local circumstances in relation to a target area requires an analysis of site-specific deforestation drivers and land use characteristics. This study aimed to analyze the capability of forest-dependent people to find the way for reducing pressures on forest resources, i.e. reducing shifting cultivation and identified their patterns of land and forest use, as this knowledge is essential for developing a REDD plus for land and forest management for an area. The study target area was Luang Prabang Province in the northern part of the Lao People’s Democratic Republic (Lao PDR). We conducted questionnaire-based surveys and participatory workshops to identify the drivers of deforestation and forest degradation as well as current local capabilities. Our findings, which focused on the characteristics of ethnic groups (Khmu and Hmong) and the agricultural techniques used by villagers, revealed significant differences between upland rice farmers without paddy fields and farmers with paddy fields who cultivated upland rice in terms of their capabilities to maintain livelihoods. The results of a discriminant function analysis indicated that 66.7% of the initially categorized respondents were correctly classified for the variable Khmu or Hmong and 82.1% classified for the variable upland rice farmers with paddy or upland rice farmers without paddy. The results indicated a lower capability to transition to alternative livelihoods among farmers relying on upland cultivation (i.e. shifting cultivation) than among farmers who cultivate paddy. Moreover, the study revealed the importance of applying a capability approach when planning REDD plus in Lao PDR that account for differential capabilities attribut

关键词： Capability Approach Capacity Building Deforestation Drivers Safeguards

Prognosis of metastatic splenic hilum lymph node in patients with gastric cancer after total gastrectomy and splenectomy

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World Journal of Hepatology 2010年第2期2卷 81-86页

作者： Keishiro Aoyagi Kikuo Kouhuji motoshi Miyagi Takuya Imaizumi Junya Kizaki Kazuo Shirouzu Department ofSurgery Kurume University School of MedicineFukuoka830-0011Japan

AIM:To clarify the significance of combined resection of the spleen to dissect the No.10 lymph node(LN). METHODS:We studied 191 patients who had undergone total gastrectomy with splenectomy,excluding non-curative cases,resection of multiple gastric cancer, and those with remnant stomach *** clinico-pathological factors were evaluated for any independent contributions to No.10 LN metastasis,usingχ 2 test. Significant factors were extracted for further analysis, carried out using a logistic regression ***,lymph node metastasis was evaluated for any independent contribution to No.10 LN metastasis,using the same *** cumulative survival rate was calculated using the Kaplan-Meier *** significance of any difference between the survival curves was determined using the Cox-Mantel test,and any difference was considered significant at the 5%level. RESULTS:From the variables considered to be potentially associated with No.10 LN metastasis,age, depth,invasion of lymph vessel,N factor,the numberof lymph node metastasis,Stage,the number of sites, and location were found to differ significantly between those with metastasis(the Positive Group)and those without(the Negative Group).A logistic regression analysis showed that the localization and Stage were significant parameters for No.10 LN *** was no case located on the lesser curvature in the Posi-tive *** numbers of No.2,No.3,No.4sa,No. 4sb,No.4d,No.7,and No.11 LN metastasis were each found to differ significantly between the Positive Group and the Negative Group.A logistic regression analysis showed that No.4sa,No.4sb,and No.11 LN metastasis were each a significant parameter for No.10 LN *** was no significant difference in survival curves between the Positive Group and the Negative Group. CONCLUSION:Splenectomy should be performed to dissect No.10 LN for cases which have No.4sa,No. 4sb or No.11 LN ***,in cases where the tumor is located on th

关键词： Gastric cancer Lymph node metastasis Lymphadenectomy,Splenectomy Total gastrectomy

Estimation of Potential GHG Emission Reduction through Corresponded REDD Plus Activities in Remote Area in Central Kalimantan, Indonesia—Case Study in the Paduran Area

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Open Journal of Forestry 2014年第4期4卷 338-348页

作者： motoshi Hiratsuka Seiji Iwanaga Hayato Tsuzuki Hirohumi Yaginuma Faculty of Agriculture Ehime University Matsuyama Japan Faculty of Human Sciences Waseda University Tokorozawa Japan Faculty of Life and Environmental Sciences University of Tsukuba Tsukuba Japan Mitsubishi UFJ Research and Consulting Tokyo Japan

REDD plus activities corresponded in Central Kalimantan Province, Indonesia and their GHG emission reductions potential were analyzed. Target area is located in a remote area from Pa-langkaraya, Capital of Central Kalimantan Province and consisted of immigrating people mainly from Java Island. In the target area, most of local people conducted unsustainable land use activities (e.g. slash-and-burn agriculture). From analysis of past land use in the target area, there were drastic changes in land use from 1989 after migration began. Natural secondary forest with high density was greatly reduced (2010 levels are approximately 80% of 1996 levels) and converted to cropland and settlement. Also, the reduction in natural secondary forest with high density allowed Melaleuca cajuputi Powell forest to rapidly increase in size (2010 levels are approximately 3.7 times as 1996 levels). Additionally, as marked point, there was an increase in oil palm plantations from 2008 and onwards. From results of land use change in the past, mean annual GHG emissions of 5450 Gg CO2e year-1 had been continued until year 2010. To consider counter-measure for reducing GHG emissions in the target area, the relationship between past land use changes and human activities was analyzed through workshops with stakeholders of 6 different groups (village authorities, forest fire fighting team, members of farmers group, large landowners, workers outside of village and oil palm plantation and mother having small children). The results of the workshops showed that the core problem of unsustainable land use faced by 4 of the 6 groups of stakeholders was the lack of job opportunities (means to earn a living) in the target area. Also, it was learned that core groups considered oil palm plantations is to alleviate the problem and provide a source of alternative income. Furthermore, the workshops indicated that future land use scenario (reference scenario) will be based on income from oil palm plantations and,

关键词： GHG Emission Reduction REDD Plus Alternative Livelihood