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941.
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Kenta Inagaki Takatoshi Hijikata Takeshi Tsukada Tadafumi Koyama Keiji Ishikawa Shoichi Ono 《Journal of Nuclear Science and Technology》2014,51(7-8):906-915
A simulation code was developed to evaluate the performance of the cesium adsorption instrument operating in Fukushima Daiichi Nuclear Power Station. Since contaminated water contains seawater whose salinity is not constant, a new model was introduced to the conventional zeolite column simulation code to deal with the variable salinity of the seawater. Another feature of the cesium adsorption instrument is that it consists of several columns arranged in both series and parallel. The spent columns are replaced in a unique manner using a merry-go-round system. The code is designed by taking those factors into account. Consequently, it enables the evaluation of the performance characteristics of the cesium adsorption instrument, such as the time history of the decontamination factor, the cesium adsorption amount in each column, and the axial distribution of the adsorbed cesium in the spent columns. The simulation is conducted for different operation patterns and its results are given to Tokyo Electric Power Company (TEPCO) to support the optimization of the operation schedule. The code is also used to investigate the cause of some events that actually occurred in the operation of the cesium adsorption instrument. 相似文献
943.
Kiwamu Tanaka Asako Shimada Akiko Hoshi Mari Yasuda Mayumi Ozawa Yutaka Kameo 《Journal of Nuclear Science and Technology》2014,51(7-8):1032-1043
To characterize the rubble and trees contaminated by radionuclides released by the recent accident at the Fukushima Daiichi Nuclear Power Station, the radiochemical analysis protocols were modified using those developed by the Japan Atomic Energy Agency for the waste generated by research, industrial, and medical facilities. The radioactivity concentrations of gamma-ray-emitting nuclides 60Co, 94Nb, 152Eu, and 154Eu, and beta-particle-emitting nuclides 14C, 129I, 36Cl, 79Se, and 99Tc were successfully applied by the modified analytical method. In contrast, the radioactivity concentrations of 3H, 90Sr, 137Cs, and alpha-particle-emitting nuclides were applied by the conventional method. Unfortunately, 36Cl, 94Nb, 129I, 152Eu, 154Eu, and alpha-particle-emitting nuclides were below the detection limit of the conventional method. The measured radioactivity concentrations, except for that of 3H, were not uniform in the area but depended on the reactor unit. Although the radioactivity concentrations were varied widely, this analysis successfully clarified the characteristics of the radioactivity concentrations of the rubble and trees. 相似文献
944.
作为2008年奥运会的举办城市,北京将会成为国内外游客主要聚集的地区,为了向用户提供"随时随地、方便快捷"的信息查询和位置查询服务,中国网通集团研究院开发了奥运"城市通"系统,通过该系统,用户可以使用一个具有定位功能的小灵通终端进行餐饮、娱乐、观光的出行导航和综合城市信息、企业信息的查询,因此,定位技术是实现"城市通"业务的核心,为开发其他增值业务提供了基础,本文将详细介绍定位技术在"城市通"业务中的应用。 相似文献
945.
依据监控系统自身特点,结合广西龙滩水电站投运过程,以尽量减少对已投运设备的影响、提高项目实施过程中系统安全性为目标,总结大中型水电站监控系统投运过程中需要注意的事项。 相似文献
946.
《International Journal of Hydrogen Energy》2019,44(29):15246-15261
For optimizing locations of hydrogen refueling stations, two popular approaches represent fuel demands as either nodes or paths, which imply different refueling behavior and definitions of convenience. This paper compares path-based vs. node-based models from the perspective of minimizing total additional travel time and feasibly covering all demands with the same number of stations. For this comparison, two new station location models are introduced that extend the Flow Capturing Location Model (FCLM) and p-Median Problem (PMP) by consistently defining upper limits on vehicle driving range and maximum inconvenience on refueling trips. Results for an idealized metropolitan area and Orlando, Florida show that path-based refueling substantially reduces wasteful travel time for refueling and covers more demand feasibly and more equitably in most scenarios. Path-based models incorporate the fact that residents of a zone regularly interact with other zones; therefore, individual stations can cover flows originating both near and far from their locations. This study suggests that path-based approaches to planning hydrogen refueling infrastructure enable more people in more neighborhoods to refuel fuel-cell vehicles without wasting excessive time or running out of fuel. 相似文献
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948.
949.
向家坝水电站二期纵向围堰上游段座落于厚达45~62 m的覆盖层上,为提高接头段深厚覆盖层地基承载力,且保证导流期不同江水位时的堰体稳定,优化调整方案为,将接头段和导水段改为柔性结构。详细介绍了柔性结构段基础处理中所涉及的施工程序、施工技术和异常情况处理等。二纵围堰经过了2009年和2010年两个汛期的考验,安全监测显示与实际运行表明,柔性结构体结构稳定。将导水结构堰体改为柔性结构体,不仅节约了投资,而且保证了二期截流工程按施工总进度计划实施。 相似文献
950.