巻号一覧
後続誌
34 巻, 2 号
選択された号の論文の6件中1～6を表示しています
- |<
- <
- 1
- >
- >|
-
井上 信1992 年 34 巻 2 号 p. 101-107
発行日: 1992/02/29
公開日: 2010/04/19
ジャーナル フリーPDF形式でダウンロード (2700K) -
一色 正彦, 高橋 秀武, 市川 博喜, 白井 英次1992 年 34 巻 2 号 p. 108-118
発行日: 1992/02/29
公開日: 2010/04/19
ジャーナル フリーPDF形式でダウンロード (3069K) -
村田 幹生, 野口 宏1992 年 34 巻 2 号 p. 149-152
発行日: 1992/02/29
公開日: 2010/04/19
ジャーナル フリーPDF形式でダウンロード (2511K) -
福井 正美, 林 正俊1992 年 34 巻 2 号 p. 153-160
発行日: 1992/02/29
公開日: 2010/04/19
ジャーナル フリーTritiated water (HTO), approximately 0.34 TBq leaked from the heavy water facility of the Kyoto University Research Reactor during the period of one and half years, which caused the increase of HTO concentration in water in pools. The amount (46 GBq), 13.6% of the HTO leaked was retrieved as condensate with concentrations of 3-5MBq/ml from the graphite block set adjacent to the heavy water tank. About 2.2% (7.4GBq) of the HTO leaked moved into pool waters such as primary coolant system and sub-pool via the containment building air of which concentrations have drastically changed according to the history of ventilation. After a few days of the ventilation shut down the HTO concentration in condensate in the containment building air reached a steady state with that on the concrete wall. The concentration in air under such condition decreased with a half-life of ca. 20 weeks corresponding to the attenuation of the amount absorbed in the concrete material after removing and/or isolating the HTO sources. Of the HO leaked about 80% was estimated to be exhausted soon from the source into the atmosphere, and the residue was retrieved and/or transferred into both water and concrete after discharge.抄録全体を表示PDF形式でダウンロード (2591K) -
荒川 秋雄, 関水 浩一, 川上 誠志郎1992 年 34 巻 2 号 p. 161-173
発行日: 1992/02/29
公開日: 2010/04/19
ジャーナル フリーThis paper describes schemes for automated control rod operation during an approach to critical and heatup/pressurization regions in the BWR startup process. These schemes were developed to reduce the operators' work load. In the approach to critical region, a integral-plus-proportional control scheme, using estimated reactivity, is proposed. This scheme aims to control the reactor period to the specified level and determine the critical state. During the heatup/pressurization region, a non-linear integral-plus-proportional control scheme, where the logarithm of the neutron flux and the heatup rate deviation are fed back, has been developed to prevent heatup rate overshoot and to maintain the heatup rate at the specified value.
The performance of these control schemes was evaluated using BWR simulators and compared with performances of a period feedback control and a neutron flux feedback cascade control scheme. In the approach to the critical region, the proposed method was able to hold the reactor period constant and achieved criticality faster than the period feedback control scheme. In the heatup/pressurization region, the proposed scheme also had a faster response than the cascade control scheme and showed a stable response for a disturbance caused by opening the main steam drain valves.抄録全体を表示PDF形式でダウンロード (2536K) -
多田 薫, 藤原 鉄雄, 蓮沼 正彦, 河合 光雄1992 年 34 巻 2 号 p. 174-180
発行日: 1992/02/29
公開日: 2010/04/19
ジャーナル フリーThis study is aimed at developing a cobalt-free hardfacing alloy alternative to Co based alloy, whose use in a nuclear environment is not desirable. The new alloy, presently under development, consists of Cr, Mo, Nb and Ni. Effects of these alloy contents on wear resistance were investigated at room temperature. The alloys studied contain 15-35%Cr, 7-12.5%Mo and 5-14%Nb. The wear loss of Ni-Cr-Mo-Nb alloys decreased with increasing Cr content, but showed a minimum at 30%Cr content. It also decreased with increasing Mo content, but little improvement was observed above 10%Mo. The wear loss decreased with increasing Nb content. Above 10%Nb content, it seemed to increase slightly. An increase of (Cr, Ni)2(Nb, Mo) intermetallic compound and matrix strengthening with increasing Cr, Mo and Nb contents seemed to improve the wear resistance. Enlarged CraNi2 intermetallic compounds, however, decreased the wear resistance. Ni-(25-30%)Cr-(10-12%)Mo-(8-12%)Nb alloys are desirable from a viewpoint of wear resistance.
The Ni-25%Cr-11%Mo-10%Nb alloy powder was manufactured for trial and welded on carbon steel using the plasma-transfer-arc process. Sound deposits were obtained and the weld deposit showed wear and corrosion resistance equivalent to that for Co based alloy Stellite 6.抄録全体を表示PDF形式でダウンロード (9413K)
- |<
- <
- 1
- >
- >|