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排序方式: 共有3018条查询结果,搜索用时 343 毫秒
71.
Nobuyoshi Koshino Masayuki Harada Yasuji Morita Toshiaki Kiikuchi Yasuhisa Ikeda 《Progress in Nuclear Energy》2005,47(1-4):406-413
We have developed a simple reprocessing process for spent FBR fuels using N-cyclohexyl-2-pyrrolidone (NCP) which has selective precipitation ability for UO22+ ions. It was confirmed that NCP has sufficient precipitation ability for UO22+ ions, decontamination capability (separation of UO22+ from simulated fission products), and resistance to γ-ray radiation in nitric acid solutions. These findings indicate that NCP is applicable to our reprocessing process. We have also evaluated performances of other precipitants such as N-n-propyl-2-pyrrolidone (NProP), N-n-butyl-2-pyrrolidone (NBP), and N-n-butyl-2-pyridone (NBPyr). It was found that higher decontamination factors (DFs) are obtained by using NProP and NBP. This can be interpreted that the hydrophobicity of NProP and NBP is lower than that of NCP. Furthermore, we have obtained an experimental result that the resistance of NBPyr to γ-ray radiation is superior to that of NCP. 相似文献
72.
分布式防空C~3I智能辅助决策模型 总被引:2,自引:0,他引:2
文章针对战场环境的动态性、不确定性和不可预测性,依据分布式防空C3I系统结构,对决策需求进行了分析,以战区级为背景,提出了智能辅助决策模型。 相似文献
73.
H. Araki M. Nakamura S. Harada T. Obata N. Mikhin V. Syvokon M. Kubota 《Journal of Low Temperature Physics》2004,134(5-6):1145-1151
Hydrogen in palladium, Pd-H(D), is an interesting system because of the highly mobile hydrogen and the presence of a phase boundary below 100 K. Experimentally, however, the nature of this transition has not been established. Historically this transition around 55 to 100 K has been thought to be an order-disorder transition. Such a transition would produce a phase boundary with anomalies at specific hydrogen concentrations corresponding to the specific ordered structures. In order to check this phase boundary we have performed a detailed study of the hydrogen concentration dependence of the specific heat of PdH x over the temperature range from below 0.5 K to above 100 K using PdH x specimens with x up to 0.8753. The measured heat capacity has been analyzed as the sum of contributions due to the lattice specific heat of Pd, the electronic specific heat of PdH x , and the excess contribution caused by hydrogenation of the specimen. The excess specific heat result shows a sharp peak which indicates a phase boundary with transition temperature T 1=55 K to 85 K depending linearly on the hydrogen concentration from x=0.6572 to 0.8753. We do not observe anomalies at specific x values as would be expected for the specific ordered structures. 相似文献
74.
固化剂对环氧树脂/蒙脱土纳米复合材料中蒙脱土剥离行为的影响 总被引:2,自引:0,他引:2
采用阳离子交换的方法对蒙脱土进行了有机改性,使蒙脱土由亲水性变成亲油性,并使其层间距由原来的1.2nm扩大到2.2nm。分别使用甲基四氢苯酐和4,4’-二胺基二苯基甲烷为固化剂,制备两种环氧树脂/蒙脱土纳米复合材料,并用x一射线衍射仪和透射电镜(TEM)分析有机蒙脱土在环氧树脂中的剥离行为。研究表明,固化剂的选择对有机蒙脱土的剥离行为有很大的影响,用固化剂甲基四氢苯酐和促进剂苄基二甲胺后,有机蒙脱土容易被剥离而得到剥离型的纳米复合材料,而用4,4’-二胺基二苯基甲烷固化剂未能使有机蒙脱土剥离后形成插层型纳米复合材料。 相似文献
75.
Zhou H. Ro Y. Koizumi Y. Kobayashi T. Harada H. Okada I. 《Metallurgical and Materials Transactions A》2004,35(6):1779-1787
The deformation structure after the out-of-phase thermomechanical fatigue (OP TMF) of the single-crystal (SC), Ni-based superalloy
TMS-75 has been studied. Mechanical experiments were performed at temperatures between 400 °C and 900 °C under different total
strain ranges with varying hold times in the compression stage. The lives of TMF for samples with hold times of 10 and 60
minutes dropped drastically by one order of magnitude as compared with those without it. Different structures developed during
TMF were correlated to the difference in mechanical behavior for the two cases. The dislocations in the γ phase and the stacking faults (SFs) in the γ′ phase were quantitatively analyzed by transmission electron microscopy (TEM). This work verified that shearing of the γ′ precipitates occurred with a single-dislocation mechanism rather than a dislocation-reaction mechanism. The implications
of this work on the design of superalloys are presented. 相似文献
76.
Kazushi Terada Shoji Nakamura Taro Nakao Atsushi Kimura Osamu Iwamoto Hideo Harada 《Journal of Nuclear Science and Technology》2016,53(11):1881-1888
Gamma-ray emission probabilities of 241, 243Am and 239Np have been precisely measured with gamma- and alpha-ray spectroscopic methods. The activities of the samples were determined by measuring alpha particles using a Si semiconductor detector. Gamma rays emitted from the samples were measured with a planar type High-Purity Germanium (HPGe) detector. An efficiency curve of the HPGe detector was derived with uncertainties from 0.7% to 2.5% by combining measured efficiencies and Monte Carlo simulation. The gamma-ray emission probabilities for the major gamma rays of these nuclides were determined with uncertainties less than 1.2%. 相似文献
77.
78.
Iron was recovered from blast furnace dust and high-phosphorus oolitic hematite in the presence of Na2CO3 and CaCO3 additives. The functions of Na2CO3 and CaCO3 during the coreduction roasting process were investigated by XRD and SEM-EDS analyses. Results indicate that these additives not only hinder the reduction of fluorapatite, CaCO3 also decreases the P content of direct reduced iron (DRI) by increasing the reduction alkalinity. P remains as fluorapatite in the slag, which can be removed by grinding and magnetic separation under optimal conditions. The Na2CO3 promotes hematite reduction and improves the iron recovery (εFe) by replacing the FeO from fayalite, which results in quick growth and aggregation of metallic iron and improvement of εFe in DRI. A DRI with 91.88 mass% Fe, and 0.065 mass% P can be achieved at a recovery of 87.86 mass% under the optimal condition. 相似文献
79.
AbstractChina has experienced a surge in innovation output in which state-owned enterprises (SOE) play an essential role. Using panel data of Chinese listed firms, this paper examines the influence of state ownership on innovation output at the firm level. Controlling for size, we analyse the effects of central and local government control on the number of firms’ patent applications in different time periods. Doing so, standard assumptions on state ownership’s inhibiting character are confirmed. However, we then qualify these findings by running separate models for different regions and sectors finding that the impact of state-control on innovation performance depends on a number of conditions. More precisely, state control of firms has a negative impact on innovation output in particular in China’s Northeast region and in mid-tech sectors whereas under other circumstances it does either not matter or can even exert a positive influence. 相似文献
80.
This paper presents the silicon based on-chip antenna using a LC resonator. The proposed antenna consists of a stacked capacitor and a spiral inductor on silicon substrate. The spiral inductor structure without underpass was proposed for improvement the performance of the silicon based-antenna. The resonant frequency of the fabricated antenna was measured as 465 MHz. Its return loss was 23.4 dB at resonant frequency. The antenna has a gain of ?35.75 dBi due to small size and silicon substrate. However, the fabricated antenna has good performance in the near-field. 相似文献