In this study, we synthesize tungsten oxide thin films by electrodeposition and characterize their electrochromic properties. Depending on the deposition modes, compact and porous tungsten oxide films are fabricated on a transparent indium tin oxide (ITO) substrate. The morphology and crystal structure of the electrodeposited tungsten oxide thin films are investigated by scanning electron microscopy (SEM) and X-ray diffraction (XRD). X-ray photoelectron spectroscopy is employed to verify the chemical composition and the oxidation state of the films. Compared to the compact tungsten oxides, the porous films show superior electrochemical activities with higher reversibility during electrochemical reactions. Furthermore, they exhibit very high color contrast (97.0%) and switching speed (3.1 and 3.2 s). The outstanding electrochromic performances of the porous tungsten oxide thin films are mainly attributed to the porous structure, which facilitates ion intercalation/deintercalation during electrochemical reactions.
Recent studies on enzyme reactions in organic solvents are revived. The reactions are classified into three categories: heterogeneous, biphasic and homogeneous systems. The following subjects are described and discussed about the heterogeneous system. 1) The maximal expression of enzyme activity in organic solvents in terms of water content, hydration of enzyme, and equilibriun of water between enzyme and substrate solution. 2) Solvent effect on the catalytic power of enzyme. 3) Thermostability and thermoreactivity. 4) Applications of the enzyme reactions to synthetic chemistry.
Biosurfactant have a low toxicity, good biodegradable, various structure. It can be used for a broad range of purposes in a large variety of different applications. Sorbitol mono alkyl ester synthesized by the Porcine Pancreatic lipase catalyzes transesterification reaction between a sugar alcohol and plant oils. We are examined the surface tension, emusion stability and critical micelle concentration were evaluated. Consequently It has a good properties of biosurfactant.