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Recently, it was found that flux w and charge q are a pair of complementary basic physical attributes generating elementary circuit elements. With such a finding, two basic electrical circuit laws and constitutive relations of three fundamental circuit elements are rebuilt, upon which new dynamical equations describing dynamical circuits containing memristors are established. This leads to investigation of whether the memristor is a dynamic element.

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Aims: To isolate a new exopolysaccharide bioflocculant produced by the myxobacterium Sorangium cellulosum NUST06, and to characterize its chemical composition and expolysaccharide production relative to carbon source. Methods and Results: Exopolysaccharide levels and biomass production by S. cellulosum NUST06 were analysed relative to carbon source. Glucose in the medium at a level of 3 g l )1 completely inhibited cell growth and exopolysaccharide production, but low concentrations of glucose (1-2 g l )1 ) could stimulate cell utilization of starch. The chemical composition and flocculating activity of the NUST06 exopolysaccharide was investigated. The flocculant comprised 38AE3% proteins and 58AE5% carbohydrates, of which glucose, mannose and glucuronic acid were present at 51AE3%, 39AE2% and 10AE5%, respectively. The flocculating activity of the NUST06 flocculant depended strongly on cations. Conclusions: It is feasible to produce an exopolysaccharide bioflocculant by the strain NUST06 in a mineral salts medium using starch as a carbon source. Significance and Impact of the Study: This strain may be advantageous for commercial bioflocculant production and may enrich existing knowledge of myxobacteria.

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Polytetrafluoroethylene (PTFE) coatings were prepared on Si and acrylonitrile-butadiene rubber substrates by lowenergy electron beam dispersion. The effects of substrate nature, distance of target to substrate (d ts ) and coatings thickness on the surface morphology, structure, and tribological properties of the coatings were investigated. The results showed that substrate nature affects the shape and size distribution of surface conglomerations of PTFE coatings due to the interaction process of active dispersion particles with underlying polymer layer. Surface energy of PTFE coatings decreases first with the coatings thickness increases to 1.25 μm and then slowly increases with the thickness. Structure defects (pore, interstice, and so on) in the coatings increase with the thickness increases but reduce significantly with the d ts increases. PTFE coating prepared at the d ts of 20 cm had a higher intensity of the amorphous absorption bands. Friction experiment indicated that the destroyed area of the coatings in the friction region decreases with increases the coatings thickness but increases with the d ts . The rubber modified by PTFE coatings with spherical structure possesses a higher stability in the friction process and a lower coefficient of friction.