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This study presents the effects of mixture fractions of nuclear fuels (mixture of fissile–fertile fuels and mixture of two different fertile fuels) and 6Li enrichment on the neutronic parameters (the tritium breeding ratio, TBR, the fission rate, FR, the energy multiplication ratio, M, the fissile breeding rate, FBR, the neutron leakage out of blanket, L, and the peak-to-average fission power density ratio, Γ) of a deuterium–tritium (D–T) fusion neutron-driven hybrid blanket. Three different fertile fuels (232Th, 238U and 244Cm), and one fissile fuel (235U) were selected as the nuclear fuel. Two different coolants (pressurized helium and natural lithium) were used for the nuclear heat transfer out of the fuel zone (FZ). The Boltzmann transport equation was solved numerically for obtaining the neutronic parameters with the help of the neutron transport code XSDRNPM/SCALE4.4a. In addition, these calculations were performed by also using the MCNP4B code. The sub-limits of the mixture fractions and 6Li enrichment were determined for the tritium self-sufficiency. The considered hybrid reactor can be operated in a self-sufficiency mode in the cases with the fuel mixtures mixed with a fraction of equal to or greater than these sub-limits. Furthermore, the numerical results show that the fissile fuel breeding and fission potentials of the blankets with the helium coolant are higher than with the lithium coolant. 相似文献
94.
Kanayama Gen; Amiaz Revital; Seidman Stuart; Pope Harrison G. Jr. 《Canadian Metallurgical Quarterly》2008,16(2):189
Reports an error in Testosterone supplementation for depressed men: Current research and suggested treatment guidelines by Gen Kanayama, Revital Amiaz, Stuart Seidman and Harrison G. Pope Jr. (Experimental and Clinical Psychopharmacology, 2007[Dec], Vol 15[6], 529-538). In the Recent Studies section (pp. 531-532), citations to Pope and Katz (2003) should have been to Pope, Kanayama, Cohane, Siegel, and Hudson (2003) to reflect the following source, which was omitted from the reference list: Pope, H. G., Jr., Kanayama, G., Cohane, G., Siegel, A., & Hudson, J. I. (2003). Testosterone gel supplementation for men with refractory depression: A randomized placebo-controlled trial. American Journal of Psychiatry, 160, 105-111. (The following abstract of the original article appeared in record 2007-18976-003.) Several lines of accumulating evidence suggest that testosterone might be effective for the treatment of depression, especially in older men who exhibit low testosterone levels. However, despite the potential promise of this approach, the available literature of controlled studies of testosterone in depression remains extremely limited. Therefore, testosterone treatment of depression must still be considered an experimental procedure. At the present state of research, it appears that testosterone might most likely show benefit as an augmentation strategy in men who exhibit low or borderline testosterone levels and who show only a partial response to conventional antidepressants. In this article, we provide some suggested practical guidelines for the treatment of such individuals. However, it should be recognized that these suggestions are tentative and will likely require revision as additional data become available. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
95.
以河南某低品位铝土矿作为原矿,利用实验室XFD-1.0型浮选机系统地研究了矿浆pH值、捕收剂用量、调浆转速和浮选转速对低品位铝土矿浮选的影响。试验结果表明:最佳矿浆pH值为9.5左右,捕收剂用量为1200g/t,调浆转速为2500r/min,浮选转速为2000r/min。浮选产品分析结果表明:调浆转速的提高有利于提高低品位铝土矿各个粒级的回收率,尤其是-0.038mm的细粒级,浮选转速提高也能强化-0.038mm细粒级的回收,但会造成细泥夹带,同时+0.074mm粗粒级的浮选回收率略有降低。 相似文献
96.
97.
Ji-long?Li Yan-ping?Zhao Yu-zhou?Mao Gen?ChenEmail author Jia-hui?Zhang Zhao?Chen 《Journal of Fusion Energy》2015,34(5):1067-1070
The fast ferrite tuning (FFT) real-time matching system has been designed and tested for the ion cyclotron range of frequency (ICRF) in EAST tokamak, which is necessary to transfer ICRF power to the plasma against variations in the antenna impedance. Through the test results, we proved this FFT system is feasible in EAST. Therefore this system have been upgraded recently to achieve real-time matching by the upgrading of the coil power supply and optimizing of the tuning structure. Finally the new FFT system achieved a response time of 10 ms and operated with a peak power of 1.5 MW, which satisfied the requirements of matching system in EAST. 相似文献
98.
An experimental evaluation of spatial distribution for deeply penetrating protons in carbon material
Mitsuo Tosaki Daisuke Ohsawa Yasuhito Isozumi 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2005,230(1-4):59-62
The peak profile of the 4.8-MeV resonance by the 12C(p,p)12C reaction in backscattering geometry has been analyzed to examine two kinds of stragglings of proton, i.e. the depth straggling in the incoming path and the energy loss straggling in the outgoing path. The analysis, which is combined with existing theoretical treatments for the stopping process and the energy loss straggling, has made it possible to deduce the penetration depth and its spread at the resonance position in carbon materials. The present method, as a new tool for direct inspection of ion beams inside target material, is explained in detail. 相似文献
99.
Atsushi Ikeda Tatsuya Suzuki Masao Aida Yasuhiko Fujii Toshiaki Mitsugashira Mitsuo Hara Masaki Ozawa 《Progress in Nuclear Energy》2005,47(1-4):454-461
A novel chromatographic separation technique using a tertiary pyridine type resin has been applied to the partitioning of the trivalent actinides (An) and lanthanides (Ln) and several successful results have been shown. In an alcoholic hydrochloric acid system, the trivalent An were clearly separated from the Ln, while no such group separation was achieved in an alcoholic nitric acid system. On the other hand, the nitric acid system was more effective for the intragroup (i.e. individual) separation of the trivalent An and the Ln than the hydrochloric acid system. On the basis of these results, a novel concept for the partitioning of the trivalent An and Ln using the present separation technique and its flowchart have been proposed with its advantages and disadvantages. 相似文献
100.
针对γ辐射监测系统,应用ARM微处理器控制多通道AD芯片,实现对4路输入信号的高速数据采集.详细介绍了LPC2300系列ARM与高速模数转换芯片AD7656 -1基于SPI串行通信的应用方案,给出了二者之间的硬件连接图以及μC/OS -Ⅱ实时操作系统下的软件实现方法,为ARM嵌入式系统在高速数据采集方面的应用提供了一个解决方案. 相似文献