The rheological behavior of phosphoric acid-water glass grout in different mixing ratios was studied. Grout made of water glass with Baume degree of 20° and 13.4% phosphoric acid by 1:1 volume ratio is found to b...The rheological behavior of phosphoric acid-water glass grout in different mixing ratios was studied. Grout made of water glass with Baume degree of 20° and 13.4% phosphoric acid by 1:1 volume ratio is found to be more effective in stopping water. Laboratory model test of water shutoff by grouting was conducted. Test results show that the diffusion length and water cutoff effect of the grout are significantly improved as the grout head is raised, due to the dilution of underground water, and it takes the grout longer than its gel time to cut off water.展开更多
The azeotrope disappeared when the formic acid-water mixtures were treated by membrane distillation. Membrane distillation were used for separation of formic acid-water azeotropic mixtures for the first time.
Fluorescence spectra of acetic acid-water solution excited by ultraviolet （UV） light are studied, and the relationship between fluorescence spectra and molecular association of acetic acid is discussed. The results ...Fluorescence spectra of acetic acid-water solution excited by ultraviolet （UV） light are studied, and the relationship between fluorescence spectra and molecular association of acetic acid is discussed. The results indicate that when the exciting light wavelength is longer than 246 nm, there are two fluorescence peaks located at 305 and 334 nm, respectively. By measuring the excitation spectra, the optimal wavelengths of the two fluorescence peaks are obtained, which are 258 and 284 nm, respectively. Fluorescence spectra of acetic acid-water solution change with concentrations, which is primarily attributed to changes of molecular association of acetic acid in aqueous solution. Through theoretical analysis, three variations of molecular association have been obtained in acetic acid-water solution, which are the hydrated monomers, the linear dimers, and the water separated dimers. This research can provide references to studies of molecular association of acetic acid-water, especiMly studies of hydrogen bonds.展开更多
基金Projects(41472278,41202220)supported by the National Natural Science Foundation of ChinaProject(20120022120003)supported by the Research Fund for the Doctoral Program of Higher Education,China+1 种基金Project(2652012065)supported by the Fundamental Research Funds for the Central Universities,ChinaProject supported by Beijing Higher Education Young Elite Teacher Program,China
文摘The rheological behavior of phosphoric acid-water glass grout in different mixing ratios was studied. Grout made of water glass with Baume degree of 20° and 13.4% phosphoric acid by 1:1 volume ratio is found to be more effective in stopping water. Laboratory model test of water shutoff by grouting was conducted. Test results show that the diffusion length and water cutoff effect of the grout are significantly improved as the grout head is raised, due to the dilution of underground water, and it takes the grout longer than its gel time to cut off water.
文摘The azeotrope disappeared when the formic acid-water mixtures were treated by membrane distillation. Membrane distillation were used for separation of formic acid-water azeotropic mixtures for the first time.
基金supported by the Natural Science Foundation of Jiangsu Province (No. BK2007204)the Natural Science Foundation of Jiangsu Province Educational Committee (No. 07KJD140208).
文摘Fluorescence spectra of acetic acid-water solution excited by ultraviolet （UV） light are studied, and the relationship between fluorescence spectra and molecular association of acetic acid is discussed. The results indicate that when the exciting light wavelength is longer than 246 nm, there are two fluorescence peaks located at 305 and 334 nm, respectively. By measuring the excitation spectra, the optimal wavelengths of the two fluorescence peaks are obtained, which are 258 and 284 nm, respectively. Fluorescence spectra of acetic acid-water solution change with concentrations, which is primarily attributed to changes of molecular association of acetic acid in aqueous solution. Through theoretical analysis, three variations of molecular association have been obtained in acetic acid-water solution, which are the hydrated monomers, the linear dimers, and the water separated dimers. This research can provide references to studies of molecular association of acetic acid-water, especiMly studies of hydrogen bonds.
