The effects of aggressive peat nature (pH) on the strength of peat treated by cement and cement-sodium silicate grout were investigated by evaluating the changes in unconfined compressive strength,moisture content,and...The effects of aggressive peat nature (pH) on the strength of peat treated by cement and cement-sodium silicate grout were investigated by evaluating the changes in unconfined compressive strength,moisture content,and scanning electron microscopy (SEM) of samples with time in different pH media.The results indicate that peats treated by cement-silicate have higher strength than peats treated by cement,due to an increase in pH value of the media.Furthermore,cement and cement-silicate are highly effective in reducing the moisture content and void ratio of the treated peats.The microstructures of treated peats support the laboratory test results.展开更多
Lead-free Ba(Fe_(1/2)Nb_(1/2))O_(3)/PVDF O_(3) composites were fabricated using melt.mixing technique.X-ray diffraction,scanning electron microscopy,dielectric,impedance,ac conductivity,magnetic force microscopy(MFM)a...Lead-free Ba(Fe_(1/2)Nb_(1/2))O_(3)/PVDF O_(3) composites were fabricated using melt.mixing technique.X-ray diffraction,scanning electron microscopy,dielectric,impedance,ac conductivity,magnetic force microscopy(MFM)and vibrating sample magne-tometer studies were undertaken to characterize the samples.Average crstallite size of the Ba(Fe_(1/2)Nb_(1/2))O_(3) powder,estimated using Williamson-Hall approach,was found to be~42 nm.The fller particles of~0.5-1 pum were found to disperse in the polymer matrix of all the composites.Filler concentration dependent values of real and imaginary parts of complex permittivity showed increasing trend and were seen to follow Bruggeman and Furukawa equations.The data for ac conductivity exhibited negative temperature coeficient of resistance character of the test materials and were found to obey Jonscher's power law.The correlated barier hopping model was found to explain satisfactorily the mechanism of charge transport occurring in the system.MFM confirmed the presence of magnetic phases in the composites.Typical magnetization versus applied field curves indicated the possibility of magnetoelectric coupling in the system.Hence,the present composites have shown themselves as potential multi-functional candidate materials for use in high density data storage applications.展开更多
基金the Ministry of Science,Technology Innovation,Malaysia (Project No.03-01-04-SF0889) for the financial support of this research
文摘The effects of aggressive peat nature (pH) on the strength of peat treated by cement and cement-sodium silicate grout were investigated by evaluating the changes in unconfined compressive strength,moisture content,and scanning electron microscopy (SEM) of samples with time in different pH media.The results indicate that peats treated by cement-silicate have higher strength than peats treated by cement,due to an increase in pH value of the media.Furthermore,cement and cement-silicate are highly effective in reducing the moisture content and void ratio of the treated peats.The microstructures of treated peats support the laboratory test results.
文摘Lead-free Ba(Fe_(1/2)Nb_(1/2))O_(3)/PVDF O_(3) composites were fabricated using melt.mixing technique.X-ray diffraction,scanning electron microscopy,dielectric,impedance,ac conductivity,magnetic force microscopy(MFM)and vibrating sample magne-tometer studies were undertaken to characterize the samples.Average crstallite size of the Ba(Fe_(1/2)Nb_(1/2))O_(3) powder,estimated using Williamson-Hall approach,was found to be~42 nm.The fller particles of~0.5-1 pum were found to disperse in the polymer matrix of all the composites.Filler concentration dependent values of real and imaginary parts of complex permittivity showed increasing trend and were seen to follow Bruggeman and Furukawa equations.The data for ac conductivity exhibited negative temperature coeficient of resistance character of the test materials and were found to obey Jonscher's power law.The correlated barier hopping model was found to explain satisfactorily the mechanism of charge transport occurring in the system.MFM confirmed the presence of magnetic phases in the composites.Typical magnetization versus applied field curves indicated the possibility of magnetoelectric coupling in the system.Hence,the present composites have shown themselves as potential multi-functional candidate materials for use in high density data storage applications.
