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Kobayashi S.,Ehime University | Takeda T.,Ehime University | Takeda T.,Taiyo Oil Co. | Oe T.,Osaka University | And 5 more authors.
ISIJ International | Year: 2014

The growth and coarsening of Cu-particles in 18%Cr-1.5%Cu ferritic stainless steels as a function of Nb content was investigated quantitatively. The samples were solution-treated at 1 250°C and then isothermally aged at 700°C for up to 86 400 s. Fine, spherical Cu-particles nucleated and grew during aging. The radius of the Cu particles increased in proportion to the one-third power of the aging time in all the stainless steels. The radius of the Cu particles in the Nb-added stainless steels was always smaller than that in the Nb-free stainless steel. The normalized standard deviation of the size distribution of the Cu particles increased and reached saturation at a certain value during aging. The increase in the standard deviation during aging was delayed by the addition of Nb. The volume fraction of Cu particles increased and reached saturation at a certain value during aging. The addition of niobium delayed the saturation of the volume fraction of the Cu particles. The slow growth of Cu particles in Nb-added stainless steels is thought to be owing to the slow diffusion of Nb atoms from the Cu particles. © 2014 ISIJ. Source

Yamaguchi S.,Ehime University | Asamoto M.,Ehime University | Inoue S.,Ehime University | Kawahito S.,Ehime University | And 3 more authors.
Chemistry Letters | Year: 2010

CaO catalysts supported on several metal oxides and zeolites were investigated for transesterification of triolein with methanol. Zeolite-supported CaO catalysts showed high catalytic activity for transesterification compared to the metal oxide-supported CaO catalysts; among the zeolites tested in this work, mordenite exhibited the best support. The catalytic activity of mordenite-supported CaO catalyst depended on both the amount of CaO loading and the calcination temperature for catalyst precursor. © 2010 The Chemical Society of Japan. Source

Amano T.,Albemarle Corporation | Amano T.,Taiyo Oil Co. | Wilcox J.,Albemarle Corporation | Wilcox J.,Taiyo Oil Co. | And 4 more authors.
Petroleum Technology Quarterly | Year: 2012

A discussion on the most important elements of chemistry and catalyst design considerations for maximizing propylene make from the FCC unit covers classification of FCC gasoline, i.e., paraffins, iso-paraffins, olefins, naphthenes, and aromatics; parameters that impact FCC catalyst components, i.e., acidity, cracking, hydrogen transfer, and isomerization; operating parameters that should be optimized to the unit's constraints, i.e., reaction temperature, catalyst circulation rate, and hydrocarbon partial pressure in the reaction zone; and commercial application of Albemarle's AFX catalyst and technology with its unique zeolite system. Source

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