Spinel ferrites exhibit exceptional magnetic properties,making them a distinctive class of magnetic materials.The sol-gel technique was utilized for the synthesis of spinel ferrites with the chemical formula Co_(0.6)S...Spinel ferrites exhibit exceptional magnetic properties,making them a distinctive class of magnetic materials.The sol-gel technique was utilized for the synthesis of spinel ferrites with the chemical formula Co_(0.6)Sr_(0.4)Ce_(x)Fe_(2-x)O_(4). Following that,a comprehensive X-ray diffraction analysis unveiled the crystalline cubic structure of the synthesized materials.Through the utilization of the M-H loop approach,the ferromagnetic attributes of ferrites were assessed,and the assimilation of rare earth elements led to substantial enhancements in saturation magnetization,remanence,and coercivity.Spinel ferrites with a high concentration of rare earth elements have improved direct current resistivity and activation energy.The logarithm of a material's resistance increased from 5.29 to 8.12 Ω·cm as cerium is added.With a change in the amount of cerium,the activation energy goes up from 0.19 to 0.29.By changing the frequency from 5.5 to 9.5 GHz,the dielectric characteristics were determined.As the frequency goes up,the dielectric constant goes down.Spinel ferrites that have been made better in every way can be used in high-frequency applications.展开更多
A series of copper cobalt composite oxides with different composition were synthesized by solid phase reaction using citric acid as a complex agent, and characterized with XRD, BET and TPR. The effects of the copper/c...A series of copper cobalt composite oxides with different composition were synthesized by solid phase reaction using citric acid as a complex agent, and characterized with XRD, BET and TPR. The effects of the copper/cobalt ratio on the crystal structure, specific surface area, reduction performance and catalytic activity of the catalyst for xylene combustion were studied. It was found that the catalytic activity of the catalyst has close relation with the copper/cobalt ratio. The interaction between copper and cobalt improved the specific surface area and reduction properties of the samples. The catalyst sample with n (Cu)/ n (Co)=1 has the largest specific surface area, the highest activity and the lowest reduction temperature. At the same time, the experimental results indicated that the spinel CuCo 2O 4 has high catalytic activity for xylene complete oxidation. The addition of opportune copper oxide promotes the CuCo 2O 4 dispersion on the composite oxide.展开更多
基金the Deanship of Scientific Research at King Khalid University for funding this work through the large group research project under grant number (RGP2/82/44)。
文摘Spinel ferrites exhibit exceptional magnetic properties,making them a distinctive class of magnetic materials.The sol-gel technique was utilized for the synthesis of spinel ferrites with the chemical formula Co_(0.6)Sr_(0.4)Ce_(x)Fe_(2-x)O_(4). Following that,a comprehensive X-ray diffraction analysis unveiled the crystalline cubic structure of the synthesized materials.Through the utilization of the M-H loop approach,the ferromagnetic attributes of ferrites were assessed,and the assimilation of rare earth elements led to substantial enhancements in saturation magnetization,remanence,and coercivity.Spinel ferrites with a high concentration of rare earth elements have improved direct current resistivity and activation energy.The logarithm of a material's resistance increased from 5.29 to 8.12 Ω·cm as cerium is added.With a change in the amount of cerium,the activation energy goes up from 0.19 to 0.29.By changing the frequency from 5.5 to 9.5 GHz,the dielectric characteristics were determined.As the frequency goes up,the dielectric constant goes down.Spinel ferrites that have been made better in every way can be used in high-frequency applications.
文摘A series of copper cobalt composite oxides with different composition were synthesized by solid phase reaction using citric acid as a complex agent, and characterized with XRD, BET and TPR. The effects of the copper/cobalt ratio on the crystal structure, specific surface area, reduction performance and catalytic activity of the catalyst for xylene combustion were studied. It was found that the catalytic activity of the catalyst has close relation with the copper/cobalt ratio. The interaction between copper and cobalt improved the specific surface area and reduction properties of the samples. The catalyst sample with n (Cu)/ n (Co)=1 has the largest specific surface area, the highest activity and the lowest reduction temperature. At the same time, the experimental results indicated that the spinel CuCo 2O 4 has high catalytic activity for xylene complete oxidation. The addition of opportune copper oxide promotes the CuCo 2O 4 dispersion on the composite oxide.
