As a kind of formal specification language, Z has gained a position in the field of software development, but there is still no standard way of transforming Z specification into executable code that is promising in in...As a kind of formal specification language, Z has gained a position in the field of software development, but there is still no standard way of transforming Z specification into executable code that is promising in increasing the quality, reusability and maintainability of software.With the automatic programming model of software engineering, through the analysis for Z specification language, a feasible semi-automatic way of refinement and transformation is proposed, and the correctness of the procedure is also discussed.展开更多
In this study, we present a facile method to prepare thiocyanato-functionalized porous silica nanospheres. Thiocyanato functionalized silica shells were coated on positively charged cetyltrimethylammonium bromide （C...In this study, we present a facile method to prepare thiocyanato-functionalized porous silica nanospheres. Thiocyanato functionalized silica shells were coated on positively charged cetyltrimethylammonium bromide （CTAB） micelles via hydrolysis and condensation of （3-thiocyanatopropyl）triethoxysilane （TCPTES）, the CTAB cores were removed subsequently to form thiocyanato-functionalized porous sil- ica nanospheres. We demonstrate that the contents of the thiocyanato groups within the functionalized porous silica nanosphere frameworks gradually diminished as a function ofhydrothermal treatment time at 100~C until complete removal, confirmed by TGA and FTIR spectra. The data indicate that extended operation at relatively elevated temperatures may lead to the decomposition of the thiocyanato functional groups. In addition, at a lower CTAB concentration （0.0009 M）, non-porous thiocyanato functionalized sil- ica nanospheres were formed. However, increasing the CrAB concentration to 0.01 M resulted in porous nanospheres inferring that a CTAB concentration threshold is needed to form thiocyanato-functionalized porous silica nanospheres.展开更多
文摘As a kind of formal specification language, Z has gained a position in the field of software development, but there is still no standard way of transforming Z specification into executable code that is promising in increasing the quality, reusability and maintainability of software.With the automatic programming model of software engineering, through the analysis for Z specification language, a feasible semi-automatic way of refinement and transformation is proposed, and the correctness of the procedure is also discussed.
文摘In this study, we present a facile method to prepare thiocyanato-functionalized porous silica nanospheres. Thiocyanato functionalized silica shells were coated on positively charged cetyltrimethylammonium bromide （CTAB） micelles via hydrolysis and condensation of （3-thiocyanatopropyl）triethoxysilane （TCPTES）, the CTAB cores were removed subsequently to form thiocyanato-functionalized porous sil- ica nanospheres. We demonstrate that the contents of the thiocyanato groups within the functionalized porous silica nanosphere frameworks gradually diminished as a function ofhydrothermal treatment time at 100~C until complete removal, confirmed by TGA and FTIR spectra. The data indicate that extended operation at relatively elevated temperatures may lead to the decomposition of the thiocyanato functional groups. In addition, at a lower CTAB concentration （0.0009 M）, non-porous thiocyanato functionalized sil- ica nanospheres were formed. However, increasing the CrAB concentration to 0.01 M resulted in porous nanospheres inferring that a CTAB concentration threshold is needed to form thiocyanato-functionalized porous silica nanospheres.
