The pendent drop or standing bubble method is applied to measure the interfacial tensions between water and nonpolar fluids (n-hexane, n-heptane, nitrogen, oxygen and methane)up to 473K and 220MPa. The high pressure a...The pendent drop or standing bubble method is applied to measure the interfacial tensions between water and nonpolar fluids (n-hexane, n-heptane, nitrogen, oxygen and methane)up to 473K and 220MPa. The high pressure autoclave with t wo visual windows and the auxiliary equipment are described. The sizes(ca 2mm) and shapes of drops or bubbles are recorded with microscope and video camera. The use of digital image permits fast, precise determination of the contour parameters. The densit y values of the liquids or gases have been chosen from literature.A special program is proposed to calculate the interfacial tensions automatically from drop shape at given temperature and pressure. The interfacial tensions σ12 increase with pr essure for the twoliquid-liquid systems,but decrease with pressure for the three gas-liquid systems.展开更多
A mode of capillary electrochromatography(CEC) based on the dynamical adsorption of an nonpolar monolithic stationary phases with a cationic surfactant, long chain quaternary ammonium slat of cetyltrimethylammonium br...A mode of capillary electrochromatography(CEC) based on the dynamical adsorption of an nonpolar monolithic stationary phases with a cationic surfactant, long chain quaternary ammonium slat of cetyltrimethylammonium bromide(CTAB) has been developed. The effects of pH value and the concentration of cetyltrimethylammonium bromide in mobile phase on electroosmotic mobility and the retention factors of solutes were investigated.展开更多
文摘The pendent drop or standing bubble method is applied to measure the interfacial tensions between water and nonpolar fluids (n-hexane, n-heptane, nitrogen, oxygen and methane)up to 473K and 220MPa. The high pressure autoclave with t wo visual windows and the auxiliary equipment are described. The sizes(ca 2mm) and shapes of drops or bubbles are recorded with microscope and video camera. The use of digital image permits fast, precise determination of the contour parameters. The densit y values of the liquids or gases have been chosen from literature.A special program is proposed to calculate the interfacial tensions automatically from drop shape at given temperature and pressure. The interfacial tensions σ12 increase with pr essure for the twoliquid-liquid systems,but decrease with pressure for the three gas-liquid systems.
文摘A mode of capillary electrochromatography(CEC) based on the dynamical adsorption of an nonpolar monolithic stationary phases with a cationic surfactant, long chain quaternary ammonium slat of cetyltrimethylammonium bromide(CTAB) has been developed. The effects of pH value and the concentration of cetyltrimethylammonium bromide in mobile phase on electroosmotic mobility and the retention factors of solutes were investigated.