[Flocculating mechanism of microbial flocculant MBFTRJ21].

The bioflocculant MBFTRJ21 for nature soda was exploited in our lab, and its flocculating mechanism was studied. The bioflocculant produced by Lactobacillus, has some advantages, such as less dosage, better flocculating effects, and etc. MBFTRJ21 is mainly composed of polysaccharide, which is determined by Anthrone reaction, Coomassie blue reaction and Elson-Morgan method. The acting force between bioflocculant and nature soda is hydrogen bond, which is determined by xi electric potential, hydrogen bond and electrovalent bond determination. The bioflocculant is treated by heat and KIO4, which indicate the active ingredient of bioflocculant is protein and osamine. Bridge occur during flocculation process, which is determined by particle size distribution. The results showed that the flocculating mechanism of MBFTRJ21 resulted from the combination of nature soda with MBFTRJ21 by hydrogen bond at the active position of glycosaminoglycan.

[Measurement of diffusion coefficients of polar solvent and nonpolar solvent at infinite dilution in polyethylene].

Gas chromatography is a new, fast, accurate and convenient technique to study the correlation of small molecule solvents and polymer membrane materials. It can measure many parameters of dissolution and diffusing characters of a small molecule in a polymer. The retention times and the peak widths at half-height of five small molecule solvents (n-hexane, n-heptane, n-decane, ethanol and water) in the stationary phase of polyethylene were measured. The diffusion coefficients of the small molecule solvents at infinite dilution were calculated with van Deemter equation. The graph plotted according to the results of the diffusion coefficients of n-decane at infinite dilution vs temperatures agreed with the Arrhenius equation. The variance in the diffusion coefficients at infinite dilution of five small molecule solvents was analyzed according to the differences in molecular mass and polarity.