Information on phase equilibria in the Co-Al based systems which are related to some magnetic and heat resistance materials is important for their microstructural control. Recently, it was proposed with a theoretical ...Information on phase equilibria in the Co-Al based systems which are related to some magnetic and heat resistance materials is important for their microstructural control. Recently, it was proposed with a theoretical calculation on electronic band structure that some Heusler-type alloys Co2XAl （X: Cr and Mn） should be a new type of spinelectronic materials so-called half-metallic ferromagnet. In the case of the Co2CrAl, however, magnetic properties expected from the theoretical work can not been experimentally obtained and the reason has been still unknown. On the other hand, a tunneling magnetoresistance （TMR） effect due to the half-metallic properties was reported in Co2（Cr<sup>0.6 Fe<sup>0.4 ）Al alloy, but not the Co2CrAl alloy.In the present paper, it is reported that this discrepancy with the theoretical work in the Co2CrAl alloy is bought about by phase separation between A2 and B2 phases, and that the substitution of Fe for Cr can suppress the precipitation of A2 phase in the B2 phase. Such a phase separation is originally due to the miscibility gap between CoAl and Cr formed in the Co-Al-Cr ternary system as well as that reported by Hao et al. in the Ni-Co-Al-Fe system.展开更多
The present study aimed to evaluate the effect of thermal processing, press throughput and roller-die gap on pellet physical quality, protein solubility and starch gelatinization in a corn-soybean based broiler diet. ...The present study aimed to evaluate the effect of thermal processing, press throughput and roller-die gap on pellet physical quality, protein solubility and starch gelatinization in a corn-soybean based broiler diet. The different processing factors were combined in a 2 × 5 × 3 factorial arrangement with eight randomized block consisting of eight production series： two thermal processing treatments （conditioning-pelleting or conditioning-expanding-pelleting）, five press throughput levels （18, 21, 24, 27 and 30 ton/h） and three roller-die gap （0.50, 0.75 and 1.00 mm）, which resulted in 30 different processed feeds. For determination of pellet durability index （PDI）, amount of intact pellets, degree of starch gelatinization and protein solubility, one composed feed sample was collected per treatment in each of eight production series, totaling eight replicates per treatment. Data concerning the amount of intact pellet and protein solubility in KOH were transformed using a variation of Box-Cox transformation in order to fit a normal distribution （P 〉 0.05）. Pellet physical quality was enhanced by conditioning-expanding treatment （P 〈 0.01）, narrower roller-die-gap （P 〈 0.01） and reduced press throughput （P 〈 0.01）. Protein solubility in KOH was impaired （P 〈 0.01） in the expander treatment and larger roller-die distance （0.75 mm and 1.00 mm） （P 〈 0.01）. Finally, greater starch gelatinization degree was achieved in expanded treatment （P 〈 0.01） and in 1.00 mm roller-die gap （P 〈 0.05）. The factors evaluated in this study resulted in interactions and significant effects on physicochemical properties of broiler feed pellets.展开更多
文摘Information on phase equilibria in the Co-Al based systems which are related to some magnetic and heat resistance materials is important for their microstructural control. Recently, it was proposed with a theoretical calculation on electronic band structure that some Heusler-type alloys Co2XAl （X: Cr and Mn） should be a new type of spinelectronic materials so-called half-metallic ferromagnet. In the case of the Co2CrAl, however, magnetic properties expected from the theoretical work can not been experimentally obtained and the reason has been still unknown. On the other hand, a tunneling magnetoresistance （TMR） effect due to the half-metallic properties was reported in Co2（Cr<sup>0.6 Fe<sup>0.4 ）Al alloy, but not the Co2CrAl alloy.In the present paper, it is reported that this discrepancy with the theoretical work in the Co2CrAl alloy is bought about by phase separation between A2 and B2 phases, and that the substitution of Fe for Cr can suppress the precipitation of A2 phase in the B2 phase. Such a phase separation is originally due to the miscibility gap between CoAl and Cr formed in the Co-Al-Cr ternary system as well as that reported by Hao et al. in the Ni-Co-Al-Fe system.
文摘The present study aimed to evaluate the effect of thermal processing, press throughput and roller-die gap on pellet physical quality, protein solubility and starch gelatinization in a corn-soybean based broiler diet. The different processing factors were combined in a 2 × 5 × 3 factorial arrangement with eight randomized block consisting of eight production series： two thermal processing treatments （conditioning-pelleting or conditioning-expanding-pelleting）, five press throughput levels （18, 21, 24, 27 and 30 ton/h） and three roller-die gap （0.50, 0.75 and 1.00 mm）, which resulted in 30 different processed feeds. For determination of pellet durability index （PDI）, amount of intact pellets, degree of starch gelatinization and protein solubility, one composed feed sample was collected per treatment in each of eight production series, totaling eight replicates per treatment. Data concerning the amount of intact pellet and protein solubility in KOH were transformed using a variation of Box-Cox transformation in order to fit a normal distribution （P 〉 0.05）. Pellet physical quality was enhanced by conditioning-expanding treatment （P 〈 0.01）, narrower roller-die-gap （P 〈 0.01） and reduced press throughput （P 〈 0.01）. Protein solubility in KOH was impaired （P 〈 0.01） in the expander treatment and larger roller-die distance （0.75 mm and 1.00 mm） （P 〈 0.01）. Finally, greater starch gelatinization degree was achieved in expanded treatment （P 〈 0.01） and in 1.00 mm roller-die gap （P 〈 0.05）. The factors evaluated in this study resulted in interactions and significant effects on physicochemical properties of broiler feed pellets.
