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Gelation kinetics, mechanical spectra, thermal scanning rheology, and differential scanning calorimetry in aqueous solutions of gelling polymers and colloids such as starch, seaweed polysaccharides (agarose, carrageenans), microbial polysaccharides (gellan, curdlan), cellulose derivatives (methylcellulose), globular proteins, gelatin, and polyvinyl alcohol, which are used widely in foods, cosmetics, biomedical and pharmaceutical applications, are described. Some gelation processes at a constant temperature were treated by an equation of first order kinetics or by other modified equations, and the molecular mechanism of gel formation is discussed. Frequency and temperature dependences of gelling biopolymers are also described.

A study was carried out on kinetics of oxygen evolution on lead alloy anodes in sulphuric acidic electrolyte. The influence of alloy elements Ca, Ag and Sn on the overpotential of oxygen evolution was investigated. All anodes had been subjected to a pre-polarisation before the measurement of potential-current curves for oxygen evolution. The overpotential of oxygen evolution was found to be decreased when the alloy anode contained Ca and Ag, whereas it remained unchanged when the alloy anode contained Sn. For oxygen evolution on lead alloy anodes the TAFEL equation was valid. The b vulue for Pb and Pb-Ca anodes was approx. 100, for Pb-Ag, Pb-Ag-Ca anodes it was approx. 140. The a value for Pb-Ca, Pb-Ag, Pb-Ag-Ca anodes decreased with the increase of Ca or/and Ag content. The a and b value was not influenced by Sn in the anodes.

Twelve samples derived from different locations in south central area of China are treated by enrichment and spread-plate technique for initial screening. Seven chitinase-producing strains are isolated. The chitinase present in the culture supernatant of strain CS-01 possesses the maximum activity of 0.118 U/mL. Analysis of the morphological feature and the ITS rDNA sequence reveals that strain CS-01 belongs to Aspergillus fumigatus. Production of the chitinase is regulated by a inducible way and the maximum activity appears at 36 h in colloidal chitin culture. Purification of the chitinase is carried out by salting out, gel filtrate chromatography and anion exchange chromatography sequentially. Native-PAGE and SDS-PAGE indicate that the chitinase from A. fumigatus CS-01 is a monomer with the relative molecular mass estimated to be 4.50×104. Its maximum activity appears at pH 5 and 55 °C. The chitinase is stable at pH 4.0–7.5 and below 45 °C.

TiB2/C cathode composites with various contents of TiB2 were prepared and their characterizations were observed and compared. The expansion of samples due to sodium and bath penetration was tested with a modified laboratory Rapoport apparatus and the appearances of the cut sections of specimens after electrolysis were studied. The results show that the mass of TiB2/C cathode composites with mass fraction of TiB2 less than 70% appreciably increases, but that of the composites with mass fraction of TiB2 more than 70% decreases slightly after being baked. The resistance to sodium and bath penetration of TiB2/C cathode composites increases with the increase of TiB2 content, especially in the composites with high TiB2 content. TiB2/C cathode composites have high resistance to the penetration of sodium and bath as well as good wettability by molten aluminum, and keep integrality and have little change of appearance after electrolysis, which indicates that TiB2/C cathode composites can be used as inert wettable cathode for aluminum electrolysis.

Prussian blue (PB) was used as catalyst to improve the extent of graphitization of polyacrylonitrile (PAN)-based carbon fibers. PB was deposited on carbon fibers by anodic electrodeposition and the thickness of PB coating (PB content) was controlled by adjusting the electrodeposition time. PAN-based carbon fibers with PB coating were heat-treated and the extent of graphitization was measured by X-ray diffractometry and Raman spectroscopy. The results indicate that the extent of graphitization of PAN-based carbon fibers is enhanced in the presence of the coating. When the PB-coated carbon fibers were heat-treated at 1 900 °C, interlayer spacing (d 002) and crystallite size (L c) reach 0.336 8 and 21.2 nm respectively. Contrarily, the values of d 002 and L c are 0.341 4 and 7.4 nm respectively when the bare carbon fibers were heat-treated at 2 800 °C. Compared with the bare carbon fibers, PB can make the heat treatment temperature (HTT) drop more than 500 °C in order to reach the same extent of graphitization. Furthermore, the research results show that PB content also has a certain influence on the extent of graphitization at the same HTT.

The blood and tissue liquid flow are studied by microcirculation method or porous flow model. The blood flow in capillaries is studied by used the porous media flow model in this paper. The advantage of the model is to research the whole flow characteristics, and it can be used to study the blood flow in animal viscera. By used the Casson constitutive model, the differential equation of blood flow in capillaries is derived, and the characteristics of steady flow and transient flow are solved by numerical method. The result shows that the more threshold stress is, the bigger flow resistance is, and the flow is different from the newtonian fluid flow. This method is a new useful approach to study the biological fluid mechanics.