An application of metal fuel cycle technology toward Self-Consistent Nuclear Energy System (SCNES) concept

A fast reactor core and fuel cycle concept has been discussed for Self-Consistent Nuclear Energy System (SCNES) concept. This paper discussed loading material candidates for long-lived fission products (LLFPs) and LLFPs burning capability. Some of LLFPs were possible to be loaded in metal of the generated form. The potential for LLFP-confinement in the reactor system is discussed along with metallic fuel cycle concept. The proposed fuel cycle scheme is a successful candidate for SCNES concept.     

Study on demagnetizing field in coil method using FEM

The central demagnetizing factor was calculated when the B–H curve of the specimen is given by a straight line using three-dimensional axial symmetrical finite element method (FEM). It is shown that the results obtained with FEM are almost similar to those reported by Bozorth. The central demagnetizing factor was calculated and the distribution of lines of magnetic flux was examined when (1) the coil length is modified for a constant specimen length and (2) when the specimen length is changed for a constant coil length. Moreover, we examined the influence of the relative permeability on the central demagnetizing field and calculated the central demagnetizing factor for the material whose B–H curve is non-linear.     

Separation of red (Y2O3:Eu3+), blue (BaMgAl10O17:Eu2+) and green (CeMgAl10O17:Tb3) rare earth phosphors by liquid/liquid extraction

A novel process for separation of red (Y₂O₃:Eu³⁺), blue(BaMgAl₁₀O₁₇:Eu²⁺) and green (CeMgAl₁₀O₁₇:Tb³) rare earth fluorescent powders was proposed. At first, the blue powder can be extracted selectively from an aqueous solution using a chelating collector 2-thenoyltrifluoroacetone (TTA) dissolved in heptane at alkaline pH condition, then, chloroform was used for extracting the green powder into organic phase. The red phosphor remains in aqueous phase with potassium sodium tartrate depressant (PST). Therefore, three phosphors can be separated successfully from their artificial mixtures by liquid/liquid extraction, and grades and recovery of separated products reach respectively as follows: red is 96.9% and 95.2%, blue is 82.7% and 98.8%, green is 94.6% and 82.6%. Funded by the Scientific Research Foundation for the Returned Overseas Chinese Scholars, State Education Ministry (ROCS, SEM [2005] No. 383)     

A Machinable Calcia–Alumina–Yttria–Silica Glass-Ceramic

It is found that a crystallized aluminosilicate glass having needlelike Ca₄Y₆O(SiO₄)₆ crystals is machinable. Densities, Vickers hardnesses, Young's moduli, thermal expansion coefficients, and fracture toughnesses of the crystallized glasses were measured.     

铜合金的疲劳寿命预测

采用平面弯曲疲劳试验,测定了C1100P-1／4H纯铜和C2801P-1／4H黄铜的S-N曲线。结果表明,实验铜合金没有疲劳极限。随外加交变应力增大,疲劳寿命缩短。在相同外加应力条件下,轧制态合金的疲劳寿命高于退火态合金的疲劳寿命。利用Manson—Coffin法则和塑性应变幅与疲劳循环次数的理论关系,通过计算得到了铜合金的理论S-N关系曲线,与实验结果吻合较好,表明该理论S-N关系曲线可用来预测铜合金的疲劳寿命。     

A pulsed-field gel electrophoresis typing scheme for Vibrio parahaemolyticus isolates from fifteen countries

Vibrio parahaemolyticus is an important foodborne pathogen in Taiwan and many other maritime Asian countries where seafood is frequently consumed. A total of 535 strains of V. parahaemolyticus were recovered mostly (97%) from clinical samples obtained in Taiwan or in 14 other countries. These strains were typed by pulsed-field gel electrophoresis following SfiI digestion and a typing scheme was generated. The 115 different patterns identified were grouped into 13 types with dissimilarity values less than 15, plus 16 miscellaneous patterns not grouped into any of the types. Types I, A, D and J contained the most patterns, with the numbers of patterns being 17, 13, 12, and 11, respectively. However, types I, B, D, A, H and C contained the most strains, with the numbers of strains being 204, 73, 71, 54, 29 and 25, respectively. Type I consisted exclusively of the pandemic O3:K6 strains and genetically closely related strains. This PFGE typing scheme for V. parahaemolyticus could be used for the characterization of pathogenic isolates.     

Molybdenum (IV) pyrophosphate isostructural with ZrP2O7

A new molybdenum pyrophosphate, MoP₂O₇, isomorphic with ZrP₂O₇, was prepared at the reductive atmosphere and its magnetic property was measured. The lattice constant of this compound was determined to be $\text{a}\text{=7.952(4)}\text{A}\text{?}$ in the cubic system. A paramgnetic behavior was observed from the liquid N₂ temperature to 500K. The effective magnetic moment for this compound was calculated to be 2.6μ_B in agreement with the calculated spin-only value of 2.83μ_B for Mo⁴⁺.     

Chemical erosion and sputtering of solid surfaces with liquid cluster ions

The sputtering phenomena of solid surfaces such as Si(111) and SiO₂ surfaces were investigated using ethanol and water cluster ion beams. To be compared with Ar monomer ion irradiation, the sputtering yield of Si surfaces was approximately 100 times higher for ethanol cluster ion irradiation and approximately 10 times higher for water cluster ion irradiation. Furthermore, for the ethanol cluster ion irradiation, chemical erosion such as silicon hydride and hydro-carbide reaction occurred on the Si surface, which resulted in the high-rate sputtering of the surface. On the other hand, for the water cluster ion irradiation, oxidation occurred on the Si surface, and physical sputtering was performed on the surface. Based on these results, chemical reaction at a nano-scale area on the Si(111) surfaces was discussed from the thermodynamic approach, and the impact of cluster ions on the surface exhibited high temperature such as a few tens of thousands degrees, which resulted in the enhancement of the chemical reaction. Thus, liquid cluster ion irradiation exhibited unique erosion and sputtering even at room temperature, which were not obtained by a conventional wet process.     

离散时间MIMO系统极限零点的稳定性

不稳定零点限制了系统可达到的控制性能, 当采用ZOH对一个连续系统进行离散化, 零点的稳定性不能得到保证. 针对无限初等因子次数为2或3时, MIMO系统极限零点的渐近特性和稳定条件不确知问题, 分析了在ZOH条件下, 当采样周期T→0时离散时间系统极限零点的渐近特性, 推导出了关于极限零点稳定性的线性近似公式和保证极限零点稳定的条件, 并给出了详细的证明. 所给出的定理是对Ishitobi定理的进一步扩展.     

Composite heat transfer with thermal radiation in non-grey medium part I: Interaction of radiation with conduction

The energy equation including thermal radiation is a non-linear high order integro-differential equation and the spectroscopic constants involved are usually complex functions of frequency. Accordingly, it is formidable to solve the equation rigorously. On this basis many investigators have introduced the assumption of the grey gas that spectroscopic constants are independent of wavelength. This assumption, however, might smear the essential feature of radiative heat transfer. Alternatively dividing a spectral band into parts of center and wings and estimating an appropriate effective absorption coefficient in each part, the opaque (Rosseland) approximation is applicable to the central part in a band and the transparent approximation to the part of wings. Such an analytical procedure reduces to simple treatment despite of taking into account of non-grey behaviour. The current study considers a simple interaction problem between conduction and radiation excluding the convection in the mediums. Numerical calculations are performed on carbon monoxide and carbon dioxide.