The effect of drying method on the properties and nanoscale structure of cellulose whiskers

Cellulose whiskers were prepared from wood- and cotton-based microcrystalline cellulose and dried by two methods: freeze-drying or air-drying. The effect of drying method on the properties and structure of the whiskers were studied. Furthermore, the influence of the source of cellulose on the nanoscale structure was investigated. Drying method was observed to slightly influence the thermal stability of cellulose whiskers, whereas the char residue varied significantly depending on the drying process performed. Small- and wide-angle X-ray scattering and solid state nuclear magnetic resonance spectroscopy were used to examine the crystallinity and nanoscale structure of the dried whiskers. It was observed that the crystal structure and crystallinity of cellulose whiskers remained during all treatments, whereas their nanoscale structure was significantly influenced by drying method, neutralization, and source of cellulose. Relationships between thermal behavior and nanoscale structure were reported and discussed.     

Intercalation current generation in oxygen- and sulfur-doped talc

The effect of oxygen and sulfur doping of talc on the parameters of Li+ intercalation current generation was studied. The X-ray structural analysis and impedance spectroscopy data and the shape of the discharge curves indicate that the doping changed the crystal and electronic structure of the material. This deter-mines the difference in the character of the change in the intercalation parameters. Modification of talc with oxygen improved the discharge characteristics of cells with talc-based cathodes.     

Synthesis of cinnoline 1-oxides by the reaction of ortho-fluoronitrobenzenes with enediamines

Reaction of α-carbonylacetamidines existing in the enediamine tautomeric form with the substituted ortho-fluoronitrobenzene afforded products of the replacement of the fluorine by the α-C atom of amidine. The latter underwent cyclization into cinnoline 1-oxides on treatment with sodium hydride.     

Adhesion-strong polymeric layers on polyethylene terephthalate films modified by irradiation with accelerated electrons

Regular trends in variation of the functional group composition, surface energy, and amorphous-crystalline structure of oriented polyethylene terephthalate films modified by irradiation with accelerated electrons to the absorbed dose in the range 25–300 kGy were studied by the methods of surface tension, indicator dye adsorption, and X-ray diffraction. The possibility of preparing gelatin emulsion layers exhibiting high adhesion strength was examined.     

Topochemistry regularities in evaluation technique of phosphate raw material reactivity

Experimental approaches for evaluation of reactivity of phosphate raw material and obtaining additional information on its phase composition were suggested in view of physicochemical patterns of the phosphate raw material decomposition in a weakly acidic environment.     

Synthesis of high-purity lower silicon alcoholates for new technology

Purification of a number of silicon derivatives (chloride, lower alcoholates) formed in processing of high-purity silicon for electronic and electrical industries was considered. It was found that high-purity substances suitable for use in electronics and optics can be produced from industrial wastes.     

Synthesis of 1,3,6-triaryl-6-trifluoromethyl-5,6-dihydro-1,3,5-triazine-2,4(1H,3H)-diones by reaction of aryl trifluoromethyl ketone imines with aryl isocyanates

Russian Journal of Organic Chemistry -     

9α-hydroxylation of 25-fluoroponasterone a diacetonide in lithium-ammonia solution

25-Fluoroponasterone A diacetonide reacted with lithium in liquid ammonia to give 25-fluoro-9α,20-dihydroxyecdysone diacetonide whose hydrolysis afforded 25-fluoro-9α,20-dihydroxyecdysone 20,22-acetonide. Nonfluorinated analog of the latter was isolated previously from Silene italica ssp. nemoralis.