The two novel green oxidation processes of p/o-cresols to p/o-hydroxybenzaldehydes catalyzed by metalloporphyrins in the presence of molecular oxygen were developed in this work.Among the metalloporphyrins with different central ions and substituents studied,T(p-NO 2)PPCoCl and T(p-OCH 3)PPFeCl presented the highest activities for p-cresol and o-cresol oxidation reactions respectively.The molar ratio of sodium hydroxide to cresols and different reaction parameters including reaction temperature,reaction time and reaction pressure have been investigated,and 69.8%/50.4% conversions of p/o-cresol and 86.6%/26.6% selectivities for p/o-hydroxybenzaldehydes were reached under optimized conditions.
Rapid and sensitive recognition of herbal pieces according to different concocted processing is crucial to quality control and pharmaceutical effect. Near-infrared （NIR） and mid-infrared （MIR） technology combined with supervised pattern recognition based on partial least-squares discriminant analysis （PLSDA） was attempted to classify and recognize six different concocted processing pieces of 600 Areca catechu L. samples and the influence of fingerprint information preprocessing methods on recognition performance was also investigated in this work. Recognition rates of 99.24%, 100% and 99.49% for original fingerprint, multiple scatter correct （MSC） fingerprint and second derivative （2nd derivative） fingerprint of NIR spectra were achieved by PLSDA models, respectively. Meanwhile, a perfect recognition rate of 100% was obtained for the above three fingerprint models of MIR spectra. In conclusion, PLSDA can rapidly and effectively extract otherness of fingerprint information from NIR and MIR spectra to identify different concocted herbal pieces ofA. catechu.
Featuring an assembly of identical pores, through-pore anodic alumina （AAO） makes an ideal monolith-like cat- alyst support for volatile organic compound （VOC） combustion. This work employs the oxidation of toluene as a model reaction to investigate the applicability of AAO supported Pt catalysts in VOC catalytic combustion. In order to modify the microstructure of AAO, some AAO samples were exposed to hot water treatment （HWT） firstly. Re- sults show that the optimum HWT time is 18 h. Pt/HWT18 gives a toluene conversion of95%; at 200 ℃, which is comparable to the initial activity of commercial γ-A1203 particle supported Pt catalyst. Considering its confine- ment effect for the supported metal and its monolith-like compact unit, AAO support offers potential applications in VOC catalytic combustion.
