Mass Transfer Enhancement of Gas Absorption by Adding the Dispersed Organic Phases

Mass transfer enhancement of gas absorption by adding a dispersed organic phase has been studied in this work. Various dispersed organic phases （heptanol, octanol, isoamyl alcohol, heptane, octane, and isooctane） were tested respectively in the experiment. According to the theoretical model and experimental data, the overall volumetric mass transfer coefficient and enhancement factor were obtained under different dispersed organic phase volume fraction and stirring speed. The experimental results indicate that gas-liquid mass transfer is enhanced at different level by adding a dispersed organic phase. The best performance of enhancement were achieved with the dispersed organic phase volumetric fraction of 5% and under an intermediate stirring speed of 670 r·min^-1. Among the organic phases tested in the experiment, alcohols show better performance, which gave 20% higher enhance-ment of overall volumetric mass transfer coefficient than adding alkanes.

A RP-HPLC method for determination of paclitaxel in its solid dispersion

Aim To develop and validate a RP-HPLC method for the analysis of paclitaxel in a solid dispersion. Methods Paclitaxel and the internal standard norethisterone were separated using a Phenomenex ODS 3 column and monitored at a wavelength at 227 nm. The isocratic mobile phase consisting of methanol-acetonitrile-water （40：30：30, V/V） was pumped at a flow-rate of 1.0 mL·min^-1. The dissolution studies were performed according to published studies. Results Under these chromatographic conditions, the calibration curve was linear in the range of 4-40 μg·mL ^-1 with the correlation coefficient of 0.9999. The mean recovery was 98.42 % （RSD = 1.19 %）. At the 60 min time point, the dissolution of paclitaxel from the solid dispersion was nearly 100 %, however, the original form of paclitaxel was about 30 %. Conclusion The method was proven to be specific, accurate and precise for determining the dissolution of paclitaxel from solid dispersion.

Separation of Quercentin by Pre-dispersed Solvent Extraction

Pre-dispersed solvent extraction (PDSE) was used to extract quercentin from its diluted solution. The influences of temperature, phase volume ratio (PVR), concentration of sodium Dodecyl benzene sulphonate and pH value etc. on the extraction efficiency were examined. It is found that, compared with traditional extraction techniques under the same condition, a higher extraction productivity can be obtained by PDSE. The stability of colloidal liquid aphrons plays an important role in this process. In a certain scope, the extraction efficiency increases with PVR. Excessive amount of solvent is not much helpful. A new analytical method by using ultraviolet spectrometer to determine the concentration of quercentin is established.

Self-trapping Characteristics of Partially Coherent Optical Beam in Photonic Crystal Fiber under Compton Scattering

Using the mutually coherent function, the self-trapping of the circle partially coherent optical beam in the total internal reflective photonic crystal fiber(TIRPCF) under Compton scattering is studied. The study shows that the composition of the non-coherent optical beam in the optical spectrum and the diffraction effect are decreased by Compton scattering, and the probability of forming the soliton is greatly increased. The vibration peak value in the propagation, compressed degree, changed cycle, and radius of the soliton are all smaller than those before the scattering, but its coherent radius is larger than that before the scattering. In this propagation, the self-focusing plays a key role.

Transport phenomena for a spherical particle in pure extensional and simple shear flows

Particles(including solid particles,liquid drops and gas bubbles)are ubiquitous in a large number of natural processes as well as in industrial productions.Their behaviors are of fundamental importance in multiphase systems since the existence of such dispersed particles influences the momentum,mass and heat transport behaviors in these systems.Up to now,a vast body of literature has been published in dealing with the transport phenomena related to a particle surrounded by a fluid under various physical circumstances.In this paper,principal research results for the transport process of a single spherical particle in pure extensional and simple shear flows presented in the literature,including our recent work,are generally reviewed in order to give a comprehensive knowledge in this area.