Hydrophilic graphite oxide (GO) of lamellar structure was prepared by oxidation of graphite; the thickness of the individual lamellae was 6.1 Å. GO was hydrophobized by n-alkylammonium cations, and the GO-organocomplex nanocomposites were swollen in organic solvents of various polarities (ethanol, toluene, cyclohexane, n-heptane) and their binary mixtures. The binary liquid composition determined the size (15–45 Å) of the lamellar GO nanostructures. Interlamellar swelling was quantitatively characterized by XRD experiments, determination of liquid sorption excess isotherms and flow microcalorimetry.

A localization criterion for the crystal-liquid phase transition (PT) is suggested, according to which the PT starts when the ratio E_d/k_BT reaches a boundary value E_d(s)/k_BT_m, above which a solid phase, and below which, a liquid phase is located in the phase diagram. Here, E_d is the energy of the delocalization of an atom, k_B is the Boltzmann constant, T is the temperature, and E_d(s) is the energy of delocalization for the solid phase at the melting point T_m. It is shown that this criterion extends the Lindemann criterion of melting to the case of crystallization, and the Löven criterion of crystallization to the case of melting. It is shown that the localization criterion suggested is applicable both for the normally melting substances and for the substances melting with a decrease in the specific volume upon the transition into the liquid phase. The connection of the localization criterion with the vacancy and diffusional criteria of the crystal-liquid PT has been studied. The inequality T_s < T_m, where T_s is the temperature of the start of crystallization, is explained on the basis of the localization criterion. The calculations of the ratio T_s/T_m coincided well with the experimental estimates. It is indicated that the greatest value of T_s/T_m is likely to be characteristic of crystals with a bcc structure and a small value of the Grüneisen parameter. The ratio T_s/T_m has been studied at some specific points of PTs where no changes in the specific volume occurs but a finite entropy jump is observed.

Summary

The stability of the monomeric enzymes α-chymotrypsin and trypsin, and the oligomeric enzyme penicillin amidase in supercritical CO₂ has been studied. They were found to be partly denatured during the depressurization step. The degree of denaturation was larger in humid CO₂ than in dry CO₂. Enzymes with S-S bridges (α-chymotrypsin; trypsin) were denatured to a lesser degree than the enzyme without cysteine (penicillin amidase). These results and electrophoretic and spectroscopic analysis indicated that the denaturation was caused by partial unfolding during the depressurization step.

Summary

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To increase the firing temperature of the goods it is necessary to replace silica walls and roofs with magnesite-chromite or forsterite.

To hold the prescribed schedule in the furnace it is necessary to have automatic regulation of the main parameters.

To increase the life of the burners it is necessary to eliminate decomposition of methane and deposition of sooty carbon in the burner tube which is done by increasing the distance from the burner nozzle to the kiln channel and by intensely cooling the burner tubes with cold air going to the burners.

Cereals provide a good source of dietary fibre and other important compounds with nutritional potential, such as phenolic compounds, antioxidants, minerals and vitamins. Although native Andean cereals are known to have high nutritional value, their minor components have not been studied thoroughly. In this study, two varieties of a native Andean crop, kañiwa (Chenopodium pallidicaule), were investigated as sources of dietary fibre and specific antioxidant compounds. Two products, an extrudate and bran, were also prepared and their functional properties and bioactive compounds were determined. Both varieties were rich in total dietary fibre and lignin, and the phenolic components analyzed had high antioxidant activity. The extrudates had good functional properties, such as degree of gelatinization, sectional expansion index and water solubility index; the bran was high in bioactive compounds, such as total phenolics. In conclusion, kañiwa may offer an alternative to traditional cereals as a health-promoting food ingredient.

Microalgae offer potential for numerous commercial applications, among them the production of long-chain polyunsaturated fatty acids (LC-PUFAs). These valuable fatty acids are important for a variety of nutraceutical and pharmaceutical purposes, and the market for these products is continually growing. An appropriate ratio of LC-PUFA of the ω-3 and ω-6 groups is vital for “healthy” nutrition, and adequate dietary intake has strong health benefits in humans. Microalgae of diverse classes are primary natural producers of LC-PUFA. This mini-review presents an introductory overview of LC-PUFA-related health benefits in humans, describes LC-PUFA occurrence in diverse microalgal classes, depicts the major pathways of their biosynthesis in microalgae, and discusses the prospects for microalgal LC-PUFA production.