Advanced Materials Research Vol. 485

Abstract: This paper deals with the partittion-diffusion model of transport and enantioseparation of phenylalanine across hollow fiber supported liquid membranes. Observed partition coefficient between the feed phase and the membrane phase, the stripping phase and the membrane phase, mass transfer resistance of boundary layer in strip phase inside the hollow fibers, boundary layer in feed phase and the diffusion in the membrane phase are taken into account in the model equations.

Abstract: This PID temperature measurement and control experiment platform is composed of LabVIEW software, PCI-6024E data acquisition card and SC-2075 breadboard. Its hardware uses thermocouple to measure temperature and controllable silicon to control the current of the electric heater, thus to control temperature; and its software uses LabVIEW to design the front panel and block program of the control system. After the hardware experiment platform is built and connected with the program, it could realize PID temperature control and high or low temperature alarm at the same time. The system is proved to have practical value and application significance.

Abstract: L-theanine was extracted by bulk liquid membrane containing Aliquat 336 as a carrier and kerosene as solvent. The effects of theanine initial concentration, carrier concentration and ion concentration in the extracting phase on separation performance were discussed and appropriate extractive conditions were established.

Abstract: A feasible driver fatigue monitoring system based on controllable infrared light is presented. This system adopts controllable infrared light to get the light and dark image of the pupil, and preprocess the image using differences, gaussian smoothing filter and binaryzation. Then the location of driver’s eyes is detected by template matching algorithm. Finally, Kalman Filter is implemented to track the eyes in order to detect the state of the eyes. This mechanism features accuracy, responsiveness and adaptability to various situations.

Abstract: A graphite furnace atomic absorption spectrometry (GFAAS) method for cadmium determination in Chinese herbal medicines was prepared. In this study, 2% (NH4)2HPO4 was used as matrix modifier, which could enhance the ashing temperature and eliminate the matrix interference.Cadmium has been determined using GFAAS method with deuterium background correction. The linear ranges of cadmium was 0 to 10 µg/L and the analytical detection limits was 0.13 µg/L, respectively. The precision relative standard deviations was 3.82% and the spike recoveries range from 97.5% to 101.3%.

Abstract: Photoelectrocatalytic oxidation of methyl orange on TiO2 films were investigated in KHCO3 solution. Electro-degradation alone could degrade little methyl orange in the solution. The film electrode prepared using PEG had less activity than the film without PEG. In the potential range from 0 to 1.3 V, degradation rate on film without PEG increased slowly until a sharp increase at potential of 1.2 V. Electrolyte concentration in the solution is not a key factor influencing degradation activity since the total potential was not high. With increasing reaction time, degradation rates on the two film electrodes increased at the same time, while the electrode prepared without PEG performed better than the electrode prepared with PEG.

Abstract: A simple and effective extraction method based on solid-phase extraction (SPE) was developed to determine chlorothalonil, metalaxyl, triadimefon, dimetachlone, procymidone, flumetralin, oxadixyl and iprodione in Panax Notoginseng using gas chromatography-mass spectrometry with selected ion monitoring (GC/MS, SIM). The prepared samples were analysed with GC-MS in the selected ion monitoring mode (SIM) using one target and two or three qualitative ions for each analyte. In the method, hexane - dichloromethane（6:4，v/v）was selected to effectively extract the pesticides from the Panax Notoginseng samples. Solid-phase extraction was carried out using Supelclean ENVI-Carb/NH2 SPE Column with acetonitrile-toluene (3:1, v/v) as the eluted solvent. In the linear range of each pesticide, the correlation coefficient was R2≥0.99. The limit of detection ranged from 0.001 to 0.05 µg.mL-1, average recoveries ranged from 79.80% to 95.00%, with relative standard deviations between 1.96% and 4.32% for all 8 pesticides.They were readily achieved with this method for all tested pesticides.

Abstract: HZSM-5 was prepared from NaZSM-5 through treatment with NH4Cl. Adsorption and photocatalytic degradation of methyl orange was investigated as the factors of HZSM-5 amount and reaction time. Adsorption of methyl orange on the mixtures varied slightly in the range from 1% to 10% when using zeolite in the concentration up to 800 mg/l. Adsorption contributed a small percent in the total decoloration of methyl orange. With increasing HZSM-5 concentration in the solution, total decoloration rate changed in a wide range. The maximum decoloration value was obtained in HZSM-5 concentration of 104 mg/l. After 70 min of irradiation, methyl orange decoloration on the mixture reached 99.5%.

Abstract: A new type composite catalyst Co-Mo/V2O5 was prepared by immersion method and characterized by XRD, BET and FT-IR. The effects of Mo mass fraction, immersion time and calcination temperature on catalyst activity for oxidation of cyclohexane were investigated. Co-Mo/V2O5 subjected to immersion with 20% ammonium molybdate solution at room temperature for 1 h and calcination at 600°C exhibited the best performance. Using 0.5 ml of cyclohexane, 3 ml of hydrogen peroxide and 30 mg of catalyst at a reaction temperature of 65°C for 3 h, the cyclohexane conversion was 32.3% and the total selectivity to cyclohexanol and cyclohexanone was 100%.

Abstract: HZSM-5 zeolite was prepared by modification of NaZSM-5 with NH4Cl and was used as support for TiO2. Maximum decoloration rates appeared when using 200 mg/l TiO2 in both photocatalysts. At TiO2 concentration below 130 mg/l, pure TiO2 could degrade more methyl orange molecules in the solution than using mixture of TiO2 and HZSM-5. At even higher photocatalyst concentrations, the mixture performed better decoloration activity than using pure TiO2. After 70 min of irradiation, nearly all of the initial methyl orange was degraded on the two photocatalysts. When using mixed photocatalysts prepared by solid state dispersion, adsorption of methyl orange was nearly constant in all the HZSM-5 using amount, which was not more than 3% of the initial methyl orange. Decoloration of methyl orange increased constantly with increasing HZSM-5 doping amount.