The present study deals with the effect of cold deformation and subsequent aging on the microstructure and mechanical properties of AI-Cu-Si-Mg alloy. Differential scanning calorimetry indicates that precipitation occ...The present study deals with the effect of cold deformation and subsequent aging on the microstructure and mechanical properties of AI-Cu-Si-Mg alloy. Differential scanning calorimetry indicates that precipitation occurs in the temperature range of 258-272℃ for the as quenched wrought alloy. The activation energy value estimated by Kissinger method for the aforesaid precipitation reaction is obtained as 106 kJ/mol. 45% cold deformation prior to aging indicates the first dissolution reaction at about 50℃ and the precipitation reaction at a temperature of about 82℃. Microstructural investigations have revealed the formation of fine precipitates within the matrix after aging of the cold deformed sample. As-quenched alloy reveals prominently the aging response, The increase in hardness, yield and tensile strength with simultaneous decrease in elongation in the deformed alloy is found to be primarily due to the deformation strengthening and not due to the precipitation hardening.展开更多
The present study deals with the development of a low carbon high strength steel by thermomechanical controlled processing on a pilot scale.The continuous cooling transformation has yielded a flat top "C" cu...The present study deals with the development of a low carbon high strength steel by thermomechanical controlled processing on a pilot scale.The continuous cooling transformation has yielded a flat top "C" curve with the phase field occupied by a mixture of bainite and martensite.The microstructure of water quenched steel essentially consists of highly dislocated lath martensite along with fine (Ti,Nb)CN precipitates and twins.High strength steel with 1217-1298 MPa yield strength and 1372-1513 MPa ultimate tensile strength along with 16-12% total elongation has been obtained in the range of 850 to 750℃ finish rolling temperature.The impact toughness value in the range of 45-72J was also achieved in the present steel.展开更多
Objective:To optimize the concentration of PDC-109 protein in semen for higher cryopreservability and fertility by sequestration or neutralization of PDC-109 by its antibodies(anti-PDC-109 antibodies)in bubaline speci...Objective:To optimize the concentration of PDC-109 protein in semen for higher cryopreservability and fertility by sequestration or neutralization of PDC-109 by its antibodies(anti-PDC-109 antibodies)in bubaline species.Methods:PDC-109 protein was purified by applying two-step chromatography procedures.Purified protein was injected in rabbits to raise antibodies.These raised anti-PDC-109 antibodies were used in neutralization or sequestration of PDC-109 in in-vitro model.Ejaculates were collected from buffaloes and splited for four groups.Group 1 received egg yolk Tris glycerol extender,without anti-PDC-109 antibodies,while group 2 to 4 received anti-PDC-109 antibodies 266μg/mL,80μg/mL,and 26μg/mL in Tris-fructose-citrate buffer,respectively.Semen quality parameters viz.,forward progressive motility,viability,total morphological abnormality,acrosomal integrity,plasma membrane integrity,cryoinjury and in-vitro zona binding index were evaluated.Results:Semen quality parameters of neat semen were within the normal range of bubaline species.Sperm motility,livability,acrosomal integrity,plasma membrane integrity,and cholesterol content of sperm were decreased and total sperm abnormality was increased significantly in post-thaw semen compared to those in pre-freeze and fresh semen(P<0.05).Semen in group 2 had higher sperm motility,livability,acrosomal integrity,plasma membrane integrity,and cholesterol content of sperm and lower total sperm abnormality significantly compared to those in group 1,3 and 4 at pre-freeze and post-thaw stages(P<0.05).Conclusions:Sequestration or neutralization of PDC-109 by its antibodies significantly improves pre-freeze,and post-thaw semen quality parameters and in-vitro zona binding index with simultaneously reducing cryoinjury or cryodamage in the sperm of bubaline species.展开更多
文摘The present study deals with the effect of cold deformation and subsequent aging on the microstructure and mechanical properties of AI-Cu-Si-Mg alloy. Differential scanning calorimetry indicates that precipitation occurs in the temperature range of 258-272℃ for the as quenched wrought alloy. The activation energy value estimated by Kissinger method for the aforesaid precipitation reaction is obtained as 106 kJ/mol. 45% cold deformation prior to aging indicates the first dissolution reaction at about 50℃ and the precipitation reaction at a temperature of about 82℃. Microstructural investigations have revealed the formation of fine precipitates within the matrix after aging of the cold deformed sample. As-quenched alloy reveals prominently the aging response, The increase in hardness, yield and tensile strength with simultaneous decrease in elongation in the deformed alloy is found to be primarily due to the deformation strengthening and not due to the precipitation hardening.
文摘The present study deals with the development of a low carbon high strength steel by thermomechanical controlled processing on a pilot scale.The continuous cooling transformation has yielded a flat top "C" curve with the phase field occupied by a mixture of bainite and martensite.The microstructure of water quenched steel essentially consists of highly dislocated lath martensite along with fine (Ti,Nb)CN precipitates and twins.High strength steel with 1217-1298 MPa yield strength and 1372-1513 MPa ultimate tensile strength along with 16-12% total elongation has been obtained in the range of 850 to 750℃ finish rolling temperature.The impact toughness value in the range of 45-72J was also achieved in the present steel.
文摘Objective:To optimize the concentration of PDC-109 protein in semen for higher cryopreservability and fertility by sequestration or neutralization of PDC-109 by its antibodies(anti-PDC-109 antibodies)in bubaline species.Methods:PDC-109 protein was purified by applying two-step chromatography procedures.Purified protein was injected in rabbits to raise antibodies.These raised anti-PDC-109 antibodies were used in neutralization or sequestration of PDC-109 in in-vitro model.Ejaculates were collected from buffaloes and splited for four groups.Group 1 received egg yolk Tris glycerol extender,without anti-PDC-109 antibodies,while group 2 to 4 received anti-PDC-109 antibodies 266μg/mL,80μg/mL,and 26μg/mL in Tris-fructose-citrate buffer,respectively.Semen quality parameters viz.,forward progressive motility,viability,total morphological abnormality,acrosomal integrity,plasma membrane integrity,cryoinjury and in-vitro zona binding index were evaluated.Results:Semen quality parameters of neat semen were within the normal range of bubaline species.Sperm motility,livability,acrosomal integrity,plasma membrane integrity,and cholesterol content of sperm were decreased and total sperm abnormality was increased significantly in post-thaw semen compared to those in pre-freeze and fresh semen(P<0.05).Semen in group 2 had higher sperm motility,livability,acrosomal integrity,plasma membrane integrity,and cholesterol content of sperm and lower total sperm abnormality significantly compared to those in group 1,3 and 4 at pre-freeze and post-thaw stages(P<0.05).Conclusions:Sequestration or neutralization of PDC-109 by its antibodies significantly improves pre-freeze,and post-thaw semen quality parameters and in-vitro zona binding index with simultaneously reducing cryoinjury or cryodamage in the sperm of bubaline species.