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15. Impact assessment of the increase in fossil fuel prices on the global energy system, with and without CO(sub 2) concentration stabilization

Author

Rout, Ullash K., Akimoto, Keigo, Sano, Fuminori, Oda, Junichiro, Homma, Takashi, and Tomoda, Toshimasa

Subjects
Energy minerals -- Prices and rates, Fossil fuels -- Prices and rates, Pricing -- Influence, Pricing -- Comparative analysis, Emissions (Pollution) -- Environmental aspects, Energy conservation -- Comparative analysis, Product price, Company pricing policy, Business, Environmental issues, Petroleum, energy and mining industries
Published
2008

18. Changes in Fruit Quality Factors in Japanese Chestnut (Castanea crenata Siebold & Zucc.) during Long-term Storage

Author

HOMMA, Takashi / INOUE, Eiichi / MATSUDA, Toshiaki / HARA, Hiromichi

Abstract

application/pdf, 論文(Article), ニホングリ(Castanea crenata Siebold & Zucc.)果実の長期貯蔵試験を2004年10月から2005年9月までポリエチレンフィルムを包装材として行った.処理区として包装材1枚区,2枚重ね区,5枚重ね区を設け,品質要因として可食部の可溶性糖含量,デンプン含量および微細構造を調査した.健全果率は貯蔵2か月後から大きく減少し,5枚区では貯蔵10か月の時点ですべての果実が商品価値を失った.袋内のガス組成は包装材の枚数が多い区ほど酸素濃度が低く,二酸化炭素濃度が高い値を示した. 果実の微細構造は貯蔵3か月で処理区間に大きな差異が観察された.すなわち,すべての処理区でデンプンの分解像が観察されたが,その進行程度は1枚区,2 枚区に比較し,5枚区で抑制されていた.5枚区では,袋内の低酸素・高二酸化炭素により果実の呼吸が抑えられ,結果としてデンプン分解が抑制されたと考えられた.最終調査日の1枚区および2枚区において,健全果ではデンプンの分解像が少なく,デンプン含量も高い値であった.この時点での健全果率は50%程度であったが,健全果ではデンプンの蓄積量が高いことから,収穫時におけるデンプン蓄積量,すなわち成熟度の高い果実ほど貯蔵性が高いことが示唆された., Long-term storage of Japanese chestnut (Castanea crenata Siebold & Zucc.) fruit using a polyethylene bag was carried out between October 2004 to September 2005. In order to create different O_2/CO_2 compositions in the bags, we used 1,2, or 5 layers of polyethylene bags. The concentrations of soluble sugars and starch and the microstructure of cotyledonary parenchyma cells were investigated as fruit quality factors. The rate of sound fruits was decreased for all treatments at 2 months of storage. When 5 layers of polyethylene bag were used, all fruits lost their commercial quality at 10 months of storage. At 3 months of storage, there were large differences in gas composition among the treatments. The higher number of polyethylene films facilitated a decrease in the O_2 content and increase in the CO_2 content. Scanning electron microscopic observation of cotyledonary parenchyma cells demonstrated that the degree of starch breakdown in each treatment was also different at 3 months of storage. Starch breakdown was extensive when 1 or 2 layers of polyethylene bag were used but was decreased when 5 layers of polyethylene bag were used. These morphological differences indicate that gas composition in the bags affects fruit respiration and reserves mobilization. The amyloplast density and starch concentration in sound fruits were relatively high at 11 months of storage when I and 2 layers of polyethylene bag were used. At this stage, although the sound fruits rate was low (approx. 50%), a high amount of storage reserves was retained in these fruits. These findings suggest that the amount of storage reserves in chestnut fruit at harvest affects fruit storability; in other words, well-matured fruits have a good potential for longterm storage.

Published
2008

20. Analysis of Technological Portfolios for CO2 stabilizations and Effects of Technological Changes

Author

Sano, Fuminori, Akimoto, Keigo, Homma, Takashi, and Tomoda, Toshimasa

Subjects
Environmental Economics and Policy
Abstract

In this study, cost-effective technological options to stabilize CO2 concentrations at 550, 500, and 450 ppmv are evaluated using a world energy systems model of linear programming with a high regional resolution. This model treats technological change endogenously for wind power, photovoltaics, and fuel-cell vehicles, which are technologies of mass production and are considered to follow the 'learning by doing' process. Technological changes induced by climate policies are evaluated by maintaining the technological changes at the levels of the base case wherein there is no climate policy. The results achieved through model analyses include 1) cost-effective technological portfolios, including carbon capture and storage, marginal CO2 reduction costs, and increases in energy system cost for three levels of stabilization and 2) the effect of the induced technological change on the above mentioned factors. A sensitivity analysis is conducted with respect to the learning rate.

Published
2005
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23. テストブランケット側壁の冷却水流量配分特性

Author

吉河 朗, Yoshikawa, Akira, 谷川 尚, Tanigawa, Hisashi, 関 洋治, Seki, Yohji, 廣瀬 貴規, Hirose, Takanori, 鶴 大悟, Tsuru, Daigo, 江里 幸一郎, Ezato, Koichiro, 横山 堅二, Yokoyama, Kenji, 西 宏, Nishi, Hiroshi, 鈴木 哲, Suzuki, Satoshi, 丹澤 貞光, Tanzawa, Sadamitsu, 本間 隆, Homma, Takashi, 榎枝 幹男, Enoeda, Mikio, 吉河 朗, Yoshikawa, Akira, 谷川 尚, Tanigawa, Hisashi, 関 洋治, Seki, Yohji, 廣瀬 貴規, Hirose, Takanori, 鶴 大悟, Tsuru, Daigo, 江里 幸一郎, Ezato, Koichiro, 横山 堅二, Yokoyama, Kenji, 西 宏, Nishi, Hiroshi, 鈴木 哲, Suzuki, Satoshi, 丹澤 貞光, Tanzawa, Sadamitsu, 本間 隆, Homma, Takashi, 榎枝 幹男, and Enoeda, Mikio

Abstract

固体増殖水冷却方式のテストブランケットモジュール(TBM)における側壁内の冷却流路は、2本の母管の間を複数の枝管で平行に接続する管路網(平行多流路)としているため、各枝管を流れる冷却水には流量の分布が生じると予想される。本研究では、平行多流路における流量分布を予測し、TBMの使用条件において構造材料を使用制限温度以下に保持するために必要となる管路網を設計することを目的とした。1次元熱計算により、必要となる冷却流量を評価した。また、圧力損失計算に基づく簡易評価により、必要な流量が得られるような管路網を設計した。塩化ビニル管を用いた試験体を用いて流量分布を測定し、設計の妥当性を確認した。この設計に基づき、F82H製の実規模試験体を製作し、流量分布と圧力損失とを計測したところ、枝管における流量の低下は最大でも平均流量の12%であり、除熱の観点からは十分に余裕があることを確認した。また、圧力損失についても計算値と実測値でよく一致した。以上の結果から、TBMの側壁における冷却管路網について、除熱の観点から必要となる流量を確保するための設計を確立することができた。, In the side wall of TBM, parallel flow channels are considered. In the cooling channels structure, the flow distribution probably arises from the pressure drop in the channels. The purpose of this study is to clarify the water flow distribution in the side wall and design the cooling channels structure so that structural material of the side wall can be kept under the allowable temperature. The structural material for assumed flow rates and the flow distribution were estimated, and then the cooling channels structure was designed. The design was verified using the mockup made of the vinyl chloride pipe. For the verified design, the mockup made of F82H is manufactured, and the water flow distribution and the pressure drop were measured. It was found that the heat removal capability was sufficient in this design. From these results, the design for the cooling channels structure in the side wall is established so that enough water flow to cool the structural material is kept., 著者所属: 日本原子力研究開発機構(JAEA), JAEA-Technology 2009-077

Published
2010

26. 核熱解析による固体増殖水冷却方式テストブランケットモジュールのトリチウム増殖比に関する検討

Author

関 洋治, Seki, Yohji, 谷川 尚, Tanigawa, Hisashi, 鶴 大悟, Tsuru, Daigo, 榎枝 幹男, Enoeda, Mikio, 秋場 真人, Akiba, Masato, 江里 幸一郎, Ezato, Koichiro, 丹澤 貞光, Tanzawa, Sadamitsu, 西 宏, Nishi, Hiroshi, 廣瀬 貴規, Hirose, Takanori, 本間 隆, Homma, Takashi, 毛利 憲介, Mori, Kensuke, 横山 堅二, Yokoyama, Kenji, 関 洋治, Seki, Yohji, 谷川 尚, Tanigawa, Hisashi, 鶴 大悟, Tsuru, Daigo, 榎枝 幹男, Enoeda, Mikio, 秋場 真人, Akiba, Masato, 江里 幸一郎, Ezato, Koichiro, 丹澤 貞光, Tanzawa, Sadamitsu, 西 宏, Nishi, Hiroshi, 廣瀬 貴規, Hirose, Takanori, 本間 隆, Homma, Takashi, 毛利 憲介, Mori, Kensuke, 横山 堅二, and Yokoyama, Kenji

Abstract

本報告は、ITERでの試験を予定している固体増殖水冷却方式のテストブランケットモジュール(TBM)について、トリチウム増殖比(TBR)に注目しつつ、層の厚さと配置を最適化するために実施した一次元核熱計算の成果をまとめたものである。今回検討を行ったTBMには、箱構造体の内部にトリチウム増殖材(Li2TiO3),中性子増倍材(Be)の微小球が層状に充填されている。増殖・増倍材の健全性が維持される最高温度以下でTBRの増加を目指し、増殖・増倍材の層の厚さを最適化した。本研究によって得られた代表的な知見を以下に示す。(1)「充填層の多層構造においても、体積比R=V(Be)/V(Li2TiO3) = 4 5にTBRの最大値が存在する。」(2)「増殖材層の背面にSingle Packingの増倍材層を2層配置することで、TBRのピーク付近であるR=4 5が可能である。」本成果は、6Li濃縮度,増倍材の充填率,増殖・増倍材層の厚さに対して、TBRを系統的にまとめたことにある。これらの結果は、TBRの見積りに貢献する一つのデータベースであり、原型炉を見据えたTBM設計の研究開発に資するものである。, This report is result of one-dimensional nuclear and thermal analyses on Test Blanket Module (TBM) for ITER emphasizing on optimized layer structures of a ceramic tritium breeder (Li2TiO3) and a beryllium neutron multiplier Be. Taking into account increment of Tritium Breeding Ratio (TBR), the radial widths of the breeder and multiplier layers are optimized. The main results of our study are as follows: (1) In multilayered structures of pebble beds, the peak of the TBR exists within the range of the volume ratio R = V(Be) / V(Li2TiO3) = 4 - 5. (2) In the case of the single packing, the R stayed in the range of 4 - 5 by setting the two layers of Be behind a layer of Li2TiO3. This database of TBR for optimized layer structures contributes to the estimation of TBR at the design stage of the TBM and demonstration blanket., 著者所属: 日本原子力研究開発機構(JAEA), JAEA-Technology 2007-067

Published
2008

41. A case of diabetic mastopathy

Author

KOBAYASHI, Kuniko, primary, FUKUNAGA, Masaharu, additional, HOMMA, Takashi, additional, SHIOMORI, Yukiko, additional, and KATO, Hiroyuki, additional

Published
2005
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