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Cyclodextrins (CDs) coupled with oils forms an insoluble inclusion complex that is able to adsorb to the interface between oils and aqueous phases; it thereby stabilizes Pickering emulsions. Three types of oils (triglyceride, linear chain oil, and ring-structured oil) were chosen to work with CDs to prepare bupivacaine (BPC)-encapsulated Pickering emulsions. We also investigated the relationship between oils and CDs; as well as their influences on stability, drug-releasing capability and skin permeability. Particle sizes and microstructures were determined by dynamic light scattering and scanning electron microscopy, respectively. In vitro drug release studies and in vitro skin permeation studies were evaluated by using Franz diffusion model. Particle sizes of all Pickering emulsions were larger than 1 μm, and the morphology was spherical and covered with rough surfaces. BPC was released over an extended period, and the releasing ratios from Pickering emulsions were only 12.2%–23.1% after 48 h. In skin permeation studies, compared with other formulations, a formula involved with ring-structured oil allowed the highest permeation amount through skin. However, after 24 h of exposure, formulation operated with linear chain oil showed the highest skin-retaining amount. These results suggest that Pickering emulsions could regulate the target site of skin depending on various types of oil used.

Algebraic equations were derived for plotting theoretical titration curves involving argentometric titration of binary halide mixtures. These generic equations are applied to three cases of binary halide mixtures in spreadsheet programs. The results are presented graphically as plots of half-cell potential versus volume of the titrant. This approach may serve as a more effective and logical method of showing students how to simulate a complex system involving multiple equilibria.

Revised structures are presented for 5- and 7-iodo-8-quinolinols and for 5- and 7-iodo-2-methyl-8-quinolinols based on NMR studies. UV spectroscopic characterization of the compounds was also carried out.

Photofragmentation of the chlorofluorocarbons, CF3Cl, CF2Cl2, and CFCl3, was investigated at 187, 125, and 118 nm using VUV harmonic generation techniques and (2+1) resonantly enhanced multiphoton ionization detection of ground Cl(2P3/20) and excited Cl*(2P1/20) state fragment atoms. Product translational energy and angular distributions were derived from Cl+ arrival time distributions obtained by time‐of‐flight mass spectrometry. Photolysis of CF3Cl at 125 and 118 nm takes place via the 4s(a1) and 4p(e) Rydberg states, respectively, and two primary fragmentation channels are observed. A ‘‘slow’’ channel with a most probable center‐of‐mass (c.m.) translational energy near zero is assigned to the production CF*3 radicals in the 2A’1, 2A‘2, and 1E’ electronically excited states. The second Cl/Cl* fragmentation channel has a c.m. translational energy distribution peaked at Etr≥1 eV and is tentatively assigned to a sequential dissociation process in which rapid C–Cl single bond rupture is followed by a second...

Photofragmentation of the chlorofluorocarbons, CF3Cl, CF2Cl2, and CFCl3, was investigated at 187, 125, and 118 nm using VUV harmonic generation techniques and (2+1) resonantly enhanced multiphoton ionization detection of ground Cl(2P3/20) and excited Cl*(2P1/20) state fragment atoms. Product translational energy and angular distributions were derived from Cl+ arrival time distributions obtained by time‐of‐flight mass spectrometry. Photolysis of CF3Cl at 125 and 118 nm takes place via the 4s(a1) and 4p(e) Rydberg states, respectively, and two primary fragmentation channels are observed. A ‘‘slow’’ channel with a most probable center‐of‐mass (c.m.) translational energy near zero is assigned to the production CF*3 radicals in the 2A’1, 2A‘2, and 1E’ electronically excited states. The second Cl/Cl* fragmentation channel has a c.m. translational energy distribution peaked at Etr≥1 eV and is tentatively assigned to a sequential dissociation process in which rapid C–Cl single bond rupture is followed by a second...

Revised structures are presented for 5- and 7-iodo-8-quinolinols and for 5- and 7-iodo-2-methyl-8-quinolinols based on NMR studies. UV spectroscopic characterization of the compounds was also carried out.