Applicability of angular flux discontinuity factor preserving region-wise leakage for integro-differential transport equation

In the current core analysis, spatial homogenization is utilized to reduce the computational time. The discontinuity factor (DF) is one of the effective correction factors to reduce spatial homogenization error. The DF in diffusion equation is widely used; on the other hand the DF in transport equation has not been put to practical use although several efforts have been carried out. In this paper, the angular flux discontinuity factor (AFDF) as the DF for the integro-differential transport equation (e.g., the discrete-ordinate method, the method of characteristics) is theoretically described and its applicability is discussed. The AFDF is used to preserve the region-wise neutron leakage at each spatial mesh and defined as a ratio of heterogeneous and homogeneous angular fluxes at the homogenized region surface. In a homogeneous calculation with the AFDF, the angular flux is discontinuous at the region surface. In this paper the applicability of the AFDF to fuel pin cell homogenization is verified for one-dimensional slab geometry. As a result of this verification, it is confirmed that the AFDF has the capability to reduce the spatial homogenization error of fuel pin cell homogenization.     

Photocatalytic Property and Electronic Structure of Lanthanide-based Oxysulfides

Lanthanide-based oxysulfides and sulfide, LnTaO_3.5S_0.5, Ln₁₀OS₁₄ (Ln = La, Pr, Nd, Sm) and La₄In₅S₁₃, were successively synthesized by sulfurization in a flowing H₂S. The sulfurization decreased the band-gap energies from >4 eV to <3eV, because of the formation of occupied S3p orbitals on the top of valence band. In accordance with the small band gap, the H₂ evolution from a 0.01 M Na₂S and 0.01 M Na₂SO₃ solution system was observed under irradiation of light up to >500 nm. The rate of H₂ evolution under light irradiation of >500 nm increased in the order of Ni/LaTaO_3.5S_0.5 < Ru/La₁₀OS₁₄ < Pt/La₄In₅S₁₃.     

Preparation of novel porous solids from alumina-pillared fluorine micas by acid-treatment

New porous solids from alumina-pillared fluorine micas (APMs), which were obtained from synthetic Na-tetrasilicic fluorine mica [NaMg_2.5Si₄O₁₀F₂], were prepared by sulfuric acid-treatment under mild conditions at 25 °C. The products were investigated by XRD, ICP, SEM, TEM and N₂ adsorption–desorption isotherm at 77 K. XRD measurements indicated that the interlayer pillared structure having a large basal spacing collapsed during the early stages of the acid-treatment. ICP analyses indicated that Al³⁺ and Mg²⁺ ions were leached out from the pillared micas during the acid-treatment. The pore properties of the leached products were found to differ from those of the mother pillared micas: the acid leaching of the pillared micas leads to the formation of mesopores around 3.2 nm in diameter. The correlation between the change in pore properties and cation elution behavior suggests that the mesopore formation results from the leaching of Mg²⁺ ions from the octahedral sheet of the pillared micas. The leached products thus obtained retained the flaky morphology of the mother pillared micas. These results show that the mild acid-treatment using APMs provides a novel route for obtaining unique mesopore solids having the large particle sizes of the mother micas.     

An energy trading system with consideration of CO2 emissions

Abatement of CO₂ emission is one of the most important issues in the 21st century regarding preservation of the earth environment. This paper addresses a utility operations planning problem for distributed energy management systems (DEMSs), where we are to obtain optimal plans that minimize both costs and CO₂ emissions. A DEMS consists of multiple entities that seek their own economic profits. In this paper, we give a mathematical formulation of the utility operations planning problem for each entity, and propose an energy trading market, which utlizes a multi‐attribute auction protocol in order to deal with both a price and a CO₂ emission rate. Experimental results show that collaboration among entities through the market provides a more profitable plan for each entity and abatement of CO₂ emission is also achieved. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 162(4): 54–63, 2008; Published online in Wiley InterScience ( www.interscience.wiley. com ). DOI 10.1002/eej.20418     

Analysis of annotations on documents for recycling of information

In order to make collaborative business activities fruitful, it is essential to know characteristics of organizations and persons in more details and to gather information relevant to the activities. In this paper, we describe a notion of “information recycling” that actualizes these requirements by analyzing documents. The key of recycling information is to utilize annotations on documents as clues for generating user profiles and for weighting contents in the context of the activities. We also propose a method of extracting annotations on paper documents just by pressing one button with the help of techniques of camera‐based document image analysis. Experimental results demonstrate that it is fundamentally capable of acquiring annotations on paper documents on the condition that their electronic versions without annotations are available for the processing. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 165(2): 60–68, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20516     

Fabrication of dense β-calcium orthophosphate with submicrometer-sized grains and its high-temperature superplastic deformation

High-density β-calcium orthophosphate (β-Ca₃(PO₄)₂, also called β-tricalcium phosphate: β-TCP) ceramics with submicrometer-sized grains were fabricated using a pulse-current pressure firing route. The maximum relative density of the β-TCP compacts was 98.7% at 1050 °C and this was accompanied by a translucent appearance. The mean grain size of the β-TCP compacts increased slightly with temperature to reach 0.78 μm at 1000 °C. However, upon further increasing the firing temperature to 1050 °C the mean grain size increased significantly to 1.6 μm. The extent of plastic deformation during tensile testing was examined at temperatures between 900 and 1100 °C using a strain rate in the range 9.26 × 10⁻⁵ to 4.44 × 10⁻⁴ s⁻¹. The maximum tensile strain achieved was 145% for a test temperature of 1000 °C and strain rate of 1.48 × 10⁻⁴ s⁻¹ and this was attributed to the relatively high density and small grain size.     

MC180295 Inhibited Epstein–Barr Virus-Associated Gastric Carcinoma Cell Growth by Suppressing DNA Repair and the Cell Cycle

DNA methylation of both viral and host DNA is one of the major mechanisms involved in the development of Epstein–Barr virus-associated gastric carcinoma (EBVaGC); thus, epigenetic treatment using demethylating agents would seem to be promising. We have verified the effect of {"type":"entrez-nucleotide","attrs":{"text":"MC180295","term_id":"1885105835","term_text":"MC180295"}}MC180295, which was discovered by screening for demethylating agents. {"type":"entrez-nucleotide","attrs":{"text":"MC180295","term_id":"1885105835","term_text":"MC180295"}}MC180295 inhibited cell growth of the EBVaGC cell lines YCCEL1 and SNU719 in a dose-dependent manner. In a cell cycle analysis, growth arrest and apoptosis were observed in both YCCEL1 and SNU719 cells treated with {"type":"entrez-nucleotide","attrs":{"text":"MC180295","term_id":"1885105835","term_text":"MC180295"}}MC180295. MKN28 cells infected with EBV were sensitive to {"type":"entrez-nucleotide","attrs":{"text":"MC180295","term_id":"1885105835","term_text":"MC180295"}}MC180295 and showed more significant inhibition of cell growth compared to controls without EBV infection. Serial analysis of gene expression analysis showed the expression of genes belonging to the role of BRCA1 in DNA damage response and cell cycle control chromosomal replication to be significantly reduced after {"type":"entrez-nucleotide","attrs":{"text":"MC180295","term_id":"1885105835","term_text":"MC180295"}}MC180295 treatment. We confirmed with quantitative PCR that the expression levels of BRCA2, FANCM, RAD51, TOP2A, and CDC45 were significantly decreased by {"type":"entrez-nucleotide","attrs":{"text":"MC180295","term_id":"1885105835","term_text":"MC180295"}}MC180295. LMP1 and BZLF1 are EBV genes with expression that is epigenetically regulated, and {"type":"entrez-nucleotide","attrs":{"text":"MC180295","term_id":"1885105835","term_text":"MC180295"}}MC180295 could up-regulate their expression. In conclusion, {"type":"entrez-nucleotide","attrs":{"text":"MC180295","term_id":"1885105835","term_text":"MC180295"}}MC180295 inhibited the growth of EBVaGC cells by suppressing DNA repair and the cell cycle.     

Analysis of ultrasonic welding process of mild steel and 5052 aluminium alloy

Ultrasonic welding of mild steel sheet (SPCC) and aluminium alloy sheet (A5052) was conducted using two different weld tips of a knurled tip (K-tip) and a curved shape tip without knurled edges (C-tip). Behaviours of the weld tip and the welded materials during the weld process were analysed using a high-speed camera observation and an image correlation. The C-tip welding shows a completely different displacement behaviour from the K-tip welding; a relative motion between the tool tip and A5052 in contact with the tip predominantly occurs in the C-tip in contrast to a relative motion between A5052 and SPCC observed in the K-tip. The joint strength using the C-tip was higher than that using the K-tip under the weld conditions in this study. It is demonstrated that the relative motion behaviour in the C-tip causes a macroscopic deformation of A5052 in the vibration direction. This phenomenon promotes growth of a bonded region, resulting in the increase of joint strength. It is surmised that Fe–Al intermetallic layer forms at the weld interface, and the joint strength consequently decreases for the longer weld time condition.