Mechanochemical synthesis of zinc ferrite, ZnFe2O4, was attempted from a powder mixture of iron (III) oxide, alpha-Fe2O3 and zinc (II) oxide, ZnO. Nanocrystalline zinc ferrite, ZnFe2O4 powders were successfully synthesized only bymilling for 30 hours. Evidence of the ZnFe2O4 formation was absent for the powders milled for 10 and 20 hours; the milling lowered the crystallinity of the starting materials. Heating after milling enhanced the formation of ZnFe2O4, crystal growth of ZnFe2O4 and the unreacted starting materials. The unreacted starting materials decreased their amounts by heating at higher temperatures.

This study was conducted to improve the durability and decrease the friction of the sintered bushing used in the joints of construction equipment. Research was carried out to examine the effects of the groove pattern on the inner surface. The following results were obtained: (1) The bushing (EK Bush) with grooves on the inner diameter showed increased durability as compared to a non-grooved bushing. (2) The helical-grooved bushing showed the least amount of wear; it was １/10 of the wear of the non-grooved bushing. (3) If the distance between grooves was decreased, then the coefficient of friction also decreased.

Sintered materials have been applied widely in Valve Seat Inserts (VSI). The demands for VSIs are not only good heat and wear resistance but also good machinability. The sintered materials, which are made of a mixture of manganese containing iron powder and certain types of sulfide powder, have superior machinability due to precipitation of the fine MnS particles in the matrix. This report introduces a new VSI material, which has both superior machinability, and wear resistance due to applies of this "MnS precipitation" technique.

Sintered materials have been applied widely in Valve Seat Inserts (VSI). The amount of wear on VSIs increases when used in gas (LPG, CNG) engines because of their dry environments. In this paper, two newly developed high performance VSI materials for gas engines are introduced. These materials applied new techniques, which are both high performance hard particle and new distribution method of solid lubricant, to increase wear resistance.

Stainless steel sludge is generated as a waste in the grinding process, and the possibility of recycling stainless steel is considered here. In this study, we considered the possibility of using the stainless steel sludge as metal powder for MIM or raw material for metal foam. For the MIM process, the metal powder will need some improvement, and flotation and spheroidizing processes of the sludge are necessary. For fabrication of the metal foam, untreated sludge can be used, and steel foam about 90% porosity is produced.

"Epigenetics" means the study of heritable changes in gene-activity without changes in DNA sequences. Methylation of the cytosine residue in a CpG dinucleotide sequence is a characteristic of the vertebrate genome. In vertebrates, methylation of DNA mainly occurs at the 5′-position of cytosine in a CpG dinucleotide forming 5-methylcytosine. Methylation of DNA plays a profound role in transcriptional repression of gene expression through several mechanisms. Generally, DNA of inactive genes is more heavily methylated than that of active ones; conversely demethylation of DNA reactivates gene expression in vivo and in vitro.