Raman spectra of the PbTiO3 films via sol-gel process were investigated by using a Jobin Yvon U1000 system. Compared with the Raman spectra of the PbTiO3 single crystals, Raman peaks of PbTiO3 films shift downward, wh...Raman spectra of the PbTiO3 films via sol-gel process were investigated by using a Jobin Yvon U1000 system. Compared with the Raman spectra of the PbTiO3 single crystals, Raman peaks of PbTiO3 films shift downward, which is attributed to the stress effect in the PbTiO3 films exerted by the substrate and the size effect on the Raman frequencies.展开更多
Photoluminescence of nanometer SiC powder was found firstly. By TEM, SAED, FTIR and chemical analyses, it is suggested that the quantum confinement effect of nanometer beta-SiC be responsible for the blue light and vi...Photoluminescence of nanometer SiC powder was found firstly. By TEM, SAED, FTIR and chemical analyses, it is suggested that the quantum confinement effect of nanometer beta-SiC be responsible for the blue light and violet emission.展开更多
A transparent bulk sodium borosilicate gel with the composition of 72SiO(2) . 23B(2)O(3) . 5Na(2)O (wt pct) was prepared by using tetraethyl orthosilicate, boric acid, sodium methoxide, sodium alkoxide, sodium acetate...A transparent bulk sodium borosilicate gel with the composition of 72SiO(2) . 23B(2)O(3) . 5Na(2)O (wt pct) was prepared by using tetraethyl orthosilicate, boric acid, sodium methoxide, sodium alkoxide, sodium acetate as precursor, methanol, ethanol and glycolic methyl ether as precursor solvent and hydrochloric acid as catalyst. Properties of gel, varied principle and related mechanism of conversion for sol to gel are discussed. Ideal composition and dry process are given in this work.展开更多
文摘Raman spectra of the PbTiO3 films via sol-gel process were investigated by using a Jobin Yvon U1000 system. Compared with the Raman spectra of the PbTiO3 single crystals, Raman peaks of PbTiO3 films shift downward, which is attributed to the stress effect in the PbTiO3 films exerted by the substrate and the size effect on the Raman frequencies.
文摘Photoluminescence of nanometer SiC powder was found firstly. By TEM, SAED, FTIR and chemical analyses, it is suggested that the quantum confinement effect of nanometer beta-SiC be responsible for the blue light and violet emission.
文摘A transparent bulk sodium borosilicate gel with the composition of 72SiO(2) . 23B(2)O(3) . 5Na(2)O (wt pct) was prepared by using tetraethyl orthosilicate, boric acid, sodium methoxide, sodium alkoxide, sodium acetate as precursor, methanol, ethanol and glycolic methyl ether as precursor solvent and hydrochloric acid as catalyst. Properties of gel, varied principle and related mechanism of conversion for sol to gel are discussed. Ideal composition and dry process are given in this work.
