The compositions Ce0.8-xSm0.2O2-δ(X=0, 0.02, 0.04, 0.06) were prepared through the sol–gel route. The effect of Pr addition on the crystal structure, densification and thermal expansion of Ce0.8Sm0.2O2-δ was studie...The compositions Ce0.8-xSm0.2O2-δ(X=0, 0.02, 0.04, 0.06) were prepared through the sol–gel route. The effect of Pr addition on the crystal structure, densification and thermal expansion of Ce0.8Sm0.2O2-δ was studied. The phase identification and morphology was studied by X-ray diffraction (XRD) and scanning electron microscopy (SEM). X-ray diffraction analysis showed that all the samples exhibit a fluorite structure. The lattice parameters? were determined by X-ray powder diffraction. Lattice parameters and volume of the unit cell increases with Pr doping. Density of the all samples is more than 90% of theoretical density. The thermal expansion was measured using dilatometric technique in the temperature range 30–1000°C. It was observed that the thermal expansion increased linearly with increasing temperature for all the samples.展开更多
A retrospective evaluation of 42 cases of podiatric brain abscess from 1985 to 1994 was performed. All patients were diagnosed by characteristic contrast-enhancement on CT scan.39 cases did not give a history of infec...A retrospective evaluation of 42 cases of podiatric brain abscess from 1985 to 1994 was performed. All patients were diagnosed by characteristic contrast-enhancement on CT scan.39 cases did not give a history of infection. The maximum diameter of the enhancement area was 2. 2cm Epileptic seizures were usually the initial and main symptoms,but local neurological signs werr absent.All of the cases were treated by antibiotic therapy.The duration of the therapy in most childhood patients was 2￣3 months,3 were over 3 months. They were followed up 1￣7 years after acute illness.Neurological sequelae were diagnosed in 3 of 42 cases.展开更多
文摘The compositions Ce0.8-xSm0.2O2-δ(X=0, 0.02, 0.04, 0.06) were prepared through the sol–gel route. The effect of Pr addition on the crystal structure, densification and thermal expansion of Ce0.8Sm0.2O2-δ was studied. The phase identification and morphology was studied by X-ray diffraction (XRD) and scanning electron microscopy (SEM). X-ray diffraction analysis showed that all the samples exhibit a fluorite structure. The lattice parameters? were determined by X-ray powder diffraction. Lattice parameters and volume of the unit cell increases with Pr doping. Density of the all samples is more than 90% of theoretical density. The thermal expansion was measured using dilatometric technique in the temperature range 30–1000°C. It was observed that the thermal expansion increased linearly with increasing temperature for all the samples.
文摘A retrospective evaluation of 42 cases of podiatric brain abscess from 1985 to 1994 was performed. All patients were diagnosed by characteristic contrast-enhancement on CT scan.39 cases did not give a history of infection. The maximum diameter of the enhancement area was 2. 2cm Epileptic seizures were usually the initial and main symptoms,but local neurological signs werr absent.All of the cases were treated by antibiotic therapy.The duration of the therapy in most childhood patients was 2￣3 months,3 were over 3 months. They were followed up 1￣7 years after acute illness.Neurological sequelae were diagnosed in 3 of 42 cases.
