IR Li2Ga2 GeS6 nonlinear crystals were directly obtained with the composition of 40 GeS2-30Ga2S3-30Li2 S, by the conventional melt-quenching method. The high depth digital image indicated that the obtained Li2Ga2 Ge S6 crystals showed a big size of 0.3 × 0.25 × 0.3 mm3. It was shown that the compound was very susceptive to H2 O with second harmonic observation. Besides, the glass-forming region of Ge S2-Ga2S3-Li2 S system was further studied by the conventional melt-quenching method.Ge S2-Ga2S3-Li2 S glass-ceramics containing IR Li2Ga2 Ge S6 nonlinear nanocrystals were obtained at a more carefully controlled heating rate.
The mesoporous silica modified with magnesium oxide(MgO) was synthesized by one step method and impregnating method,respectively.The samples were characterized by small angle X-Ray diffraction(XRD),N_2 adsorption-desorption and transmission electron microscopy(TEM),and the carbon dioxide adsorption capacity was analyzed by thermal gravimetric analysis(TGA).Compared with the original mesoporous silica(20.7 mg/g),the CO_2 adsorption capacity of MgO-modified mesoporous silica processed by one step method increases to 32.9 mg/g.Although its surface area greatly decreases compared with that of the original mesoporous silica,the MgO-modified mesoporous silica prepared by impregnating reaches an adsorptive value of 31.1 mg/g because the number of basic sites increases on the surface of the mesoporous silica.
