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Electrocatalytic oxidation technology has been proved as an efficient method for degradation in organic wastewater. The service lifetime and degradation efficiency of the electrode, one crucial struggle, limits the broad application of electrocatalytic oxidation technology. Herein, a Ru/Ir doped TiO2 electrode with a long service lifetime was developed. Accelerated life experiment showed that the service life of an electrode was 33 h when the concentration of sulfuric acid was 1 M and the current density was 2000 mA·cm−2. The influence on the phenol degradation was evaluated by researching the operating parameters. In particular, the possible mechanism of phenol removal at different pH is elucidated. It is found that acidic environment is favorable for chemical oxygen demand (COD) and phenol removal at a current density of 20 mA·cm−2, pH 3 at 800 ppm NaCl, which can make the removal rates of phenol and COD with Ru/Ir doped TiO2 anode up to 97.21% and 100%. In addition, it was demonstrated that the hydroxyl radicals play a foremost role in the degradation of phenol. Given the well stability and high service life, the Ru/Ir doped TiO2 electrode holds promise for further industrial application in wastewater treatment. [ABSTRACT FROM AUTHOR]

The 1,914-bp open reading frame of xylC from Thermoanaerobacterium saccharolyticum JW/SL-YS485 encodes a calculated 73-kDa β-xylosidase, XylC, different from any glycosyl hydrolase in the database and representing a novel glycohydrolase family. Hydrolysis occurred under retention of the anomeric configuration, and transglycosylation occurred in the presence of alcohols as acceptors. With the use of vector pHsh, expression of XylC, the third β-xylosidase in this bacterium, increased approximately 4-fold when a loop within the translational initiation region in the mRNA was removed by site-directed mutagenesis. The increased expression of xylC(m) is due to removal of a stem-loop structure without a change of the amino acid sequence of the heterologously expressed enzyme (XylC(rec)). When gel filtration was applied, purified XylC had molecular masses of 210 kDa and 265 kDa using native gradient gel electrophoresis. The protein consisted of 78-kDa subunits based on SDS gel electrophoresis and contained 6% carbohydrates. XylC and XylC(rec) exhibited maximum activity at 65°C and pH(65°C) 6.0, a 1-h half-life at 67°C, a K(m) for p-nitrophenyl-β-D-xyloside of 28 mM, and a V(max) of 276 U/mg and retained 70% activity in the presence of 200 mM xylose, suggesting potential for industrial applications.