Transient phenomena of space charge distributions in polypropylene laminated paper

In a multilayer insulator made of two or more materials with different dielectric constants and conductivities, internal space change accumulates at their interfaces. If the local field is increased by the accumulated charge, the electric durability of the insulator should be decreased. In this paper, we describe the space charge accumulation measured when oil-impregnated PPLP (polypropylene laminated paper), which consists of three layers, kraft paper, polypropylene (PP), and kraft paper, was subjected to a strong dc electric field. The experimental results suggest that internal space charge accumulates at both surfaces of a PP layer and that the electric field in the kraft paper layers disappears. © 1998 Scripta Technica, Electr Eng Jpn, 124(1): 1–6, 1998     

A Phylogenetic Analysis of Saccharomyces Species by the Sequence of 18S–28S rRNA Spacer Regions

Sequences of two internally transcribed spacer regions between 18S and 28S rRNA genes were determined to assess the phylogenetic relationship in the strains belonging to the genus Saccharomyces. The sequences of S. bayanus and S. pastorianus were quite similar, but not identical. Two phylogenetic trees constructed by the neighbor-joining method showed that all the species examined were distinguished from one another. The Saccharomyces sensu stricto species: S. cerevisiae, S. bayanus, S. paradoxus and S. pastorianus, were closely related and far from the Saccharomyces sensu lato species including S. barnetti, S. castellii, S. dairensis, S. exiguus, S. servazzii, S. spencerorum and S. unisporus, and an outlying species, S. kluyveri. © 1997 John Wiley & Sons, Ltd.     

A scheduling method considering register‐to‐register transfers

In high‐level synthesis, scheduling is an important stage which assigns each operation appearing in a data flow graph to a specific control step, whose results influence the design quality directly. This paper describes a scheduling approach for pipelined datapaths. Since few previous approaches estimate the interconnection cost between register (register‐to‐register cost), our approach introduces a datapath model with interconnection between registers across buses, and minimizes the total hardware cost including the register‐to‐register cost by force‐directed scheduling. © 1999 Scripta Technica, Electr Eng Jpn, 128(3): 63–71, 1999     

Synthesis of nanocrystalline LaF3 doped silica glasses by hydrofluoric acid catalyzed sol–gel process

Silica glasses doped with LaF₃ nanocrystals were prepared by HF-catalyzed sol–gel method. HF was used both as fluorine source and as catalyst of the sol–gel reaction, making it possible to shorten the processing time with reducing the concentration of SiOH groups to ～10¹⁸ cm^?3. The resultant glasses are transparent at visible spectral range, and the optical loss at the ultraviolet absorption edge is dominated by the Rayleigh scattering from LaF₃ crystallites. The size of LaF₃ crystallites increases with an increase in the sintering temperature and time, and is smaller than ～40 nm in samples showing good visible transparency. Green upconversion photoluminescence is observed in an Er³⁺-doped sample under excitation at 980 nm.     

Impact Force Identification of CFRP Structures Using Experimental Transfer Matrices

This paper presents a method for identifying the location and force history of an impact force acting on CFRP structures such as laminated plates and stiffened panels. The identification method is an experimental one without using any analytical model of the structure. Here, experimental transfer matrices, which relate the impact force to the corresponding responses of PZT sensors, are used to identify the impact force. The transfer matrices are preliminarily constructed from the measured data obtained by impact tests with an impulse hammer. To identify the impact location, the arrival times of the flexural waves to the PZT sensors are used, and an analog band-pass filter is used to obtain waves with a specified frequency. The wave velocity is determined experimentally from impact test results. The present method is verified experimentally by performing impact force identification of CFRP laminated plates and CFRP stiffened panels. The results reveal that the location and force history of the impact force can be identified accurately and rapidly using the present method.     

Mechanical properties of Al–Si–Cu alloys produced by the continuous casting process with heating process

The mechanical properties of aluminium alloys produced by the continuous cast process and heating process (heat-cast-sample) were investigated, where the aluminium alloys are heated continuously to high temperatures for 1 h immediately following heated mould continuous casting (HMC) and sand gravity casting (SGC). The material strength and ductility of the aluminium alloys were irregularly altered depending on the heating temperature. The mechanical properties decreased when the heating temperature increased to 400 °C and were then recovered when the temperature increased to 520 °C. However, these properties decreased again when heated to more than 540 °C. The mechanical properties of the HMC-heat-cast-sample showed overall higher than those for the SGC-sample. In addition to high tensile strength, high ductility was obtained for the HMC-520 °C samples compared with those for the as-cast-sample. Such changes were found to be directly attributable to the different severity of precipitate; moreover the crystal orientation was unchanged even after the heating process.     

Dietary Tuna Dark Muscle Protein Attenuates Hepatic Steatosis and Increases Serum High‐Density Lipoprotein Cholesterol in Obese Type‐2 Diabetic/Obese KK‐Ay Mice

Tuna muscle consists of light and dark muscle in approximately equal proportions. However, besides for the light muscle of tuna, cod, sardine, and salmon, few researches have assessed the health‐promoting functions of fish protein. Therefore, we evaluated the mechanisms underlying the alteration of lipid storage and cholesterol metabolism following the intake of tuna dark muscle protein (TDMP) by obese type‐2 diabetic/obese mice. Four‐week‐old male KK‐A^y mice were separated into 2 dietary groups, with one group receiving a casein‐based diet and the other receiving a diet with the substitution of part of the protein (50%, w/w) by TDMP (TDMP diet) for 4 wk. The TDMP diet significantly increased the content of serum high‐density lipoprotein cholesterol, partly due to the reduction of the expression of scavenger receptor class B member 1 in epididymal white adipose tissue. In addition, dietary TDMP decreased the content of hepatic triacylglycerol, which could be due to the enhancement of carnitine palmitoyltransferase‐2 activity through the activation of the expression of the peroxisome proliferative activated receptor‐α in the liver. These results suggest that TDMP could have the potential to prevent the development of obesity‐related diseases by suppressing the storage of hepatic triacylglycerol and cholesterol.     

Porcine hemoglobin promotes lipid excretion to feces more strongly than globin protein in rats

In an effort to clarify whether the lipid-lowering effect of hemoglobin is due to globin protein or heme, this study investigated the effects of dietary porcine hemoglobin (PH) and porcine globin (PG) on lipids contents of serum, liver, and feces in rats. Five-week-old male Wistar rats were divided into 3 dietary groups of 7 rats each, with one group receiving a control diet and the other groups receiving diets containing 1.25% (w/w) PH or 1.18% (w/w) PG for 4 weeks. The PH diet decreased triacylglycerol content in serum and cholesterol in serum and liver, whereas the PG diet reduced triacylglycerol content in serum and cholesterol in liver. Fecal lipid excretion in the PH group was significantly higher than in the PG group. Therefore, PH affected lipid excretion to feces due to globin protein as well as heme.     

Biodegradable β-tricalcium phosphate cement with anti-washout property based on chelate-setting mechanism of inositol phosphate

Novel biodegradable β-tricalcium phosphate (β-TCP) cements with anti-washout properties were created on the basis of chelate-setting mechanism of inositol phosphate (IP6) using β-TCP powders. The β-TCP powders were ball-milled using ZrO₂ beads for 0–6 h in the IP6 solutions with concentrations from 0 to 10,000 ppm. The chelate-setting β-TCP cement with anti-washout property was successfully fabricated by mixing the β-TCP powder ball-milled in 3,000 ppm IP6 solution for 3 h and 2.5 mass% Na₂HPO₄ solution, and compressive strength of the cement was 13.4 ± 0.8 MPa. An in vivo study revealed that the above cement was directly in contact with host and newly formed bones without fibrous tissue layers, and was resorbed by osteoclast-like cells on the surface of the cement. The chelate-setting β-TCP cement with anti-washout property is promising for application as a novel injectable artificial bone with both biodegradability and osteoconductivity.     

Hydrothermal conversion of Mg2TiO4 into brookite-type TiO2 under mild conditions

A simple and mild synthetic route via a hydrothermal treatment of Mg₂TiO₄ has been developed to prepare brookite-type TiO₂. The hydrothermal conversion of Mg₂TiO₄ to brookite proceeded in 1 M HCl solution even at 100 °C. The converted brookite grains were composed of the angular particles covered on the textured surface, leaving the original morphology of Mg₂TiO₄ grains. Compared with the commercially available TiO₂ catalysts (rutile, anatase, and P25), the brookite obtained in this study showed a good photocatalytic activity toward the oxidation of benzyl alcohol to benzaldehyde under a simulated sunlight irradiation.