Elimination of redundant operations in relational queries with general selection operators

The optimization of relational expressions concerning the elimination of “redundant” operations has been dealt with sofar for a limited class of expressions that puts restrictions on the selection operators involved. We propose a solution for the case of arbitrary selection criteria.     

Novel Wear-Resistant Superhard Diamond Composite Polycrystalline Material

Using the activated HPHT-sintering of diamond powders with addition of n-layered graphene of the N002-PDR grade, was produced a novel superhard composite polycrystalline material that does not contain free silicon and has a strength by 35% higher and wear-resistance by 7 times higher than samples produced without addition of graphene.     

Viscoelastic properties of lupin proteins produced by ultrafiltration-diafiltration

The linear and nonlinear rheological properties of defatted lupin proteins produced by ultrafiltration-diafiltration were investigated. Five concentrations ranging from 10 to 30% of the defatted ultrafiltered-diafiltered (DUD) lupin proteins were prepared. The viscoelastic properties strongly depended on concentrations. Below 12%, the DUD lupin proteins exhibited more fluid-like behavior. At 15%, lupin proteins became more viscoelastic, and above 20%, the viscoelastic solid-like properties became stronger. Below 12%, the high-frequency behaviors of moduli were proportional to ω^1/2, as expected for a semiflexible coil. Above 20%, the high-frequency behaviors of moduli were proportional to ω^1/2, indicating a flexible coil. The nonlinear steady shear rheological properties were also concentration-dependent and showed shear-thinning behavior, which could be described by a power law constitutive model. The trend of the power law exponent shift is very consistent with the linear viscoelastic behavior change with the lupin protein concentration. These results suggest DUD lupin proteins undergo a structural change between 12 and 20%.     

TiO2–CeO2 composite coatings for photocatalytic degradation of chloropesticide and organic dye

Journal of Materials Science: Materials in Electronics - Spray pyrolysis was used to deposit CeO2–TiO2 coatings on stainless steel substrates. The addition of CeO2 to TiO2 changes morphology...     

Oats protein isolate: Thermal,rheological, surface and functional properties

Oat protein isolate (OPI) was extracted in 0.015 N NaOH and acetylated or succinylated. The thermal analysis of the isolate showed a glass transition (T_g) at 43.4 °C and ΔC_p of 0.102 J/g/°C. The positive net charge of OPI and the positive or neutral charge of the modified OPI were apparent from the free capillary zone electrophoresis (FZCE) profiles. Acetylation significantly lowered foaming and emulsifying properties of OPI, while succinylation showed the highest foaming capacity, foam stability, and emulsion stability. Acetylated OPI showed the highest surface hydrophobicity compared to the other samples, while OPI was the most soluble of all. The water holding capacity of all samples analyzed was the same except for acetylated-crosslinked (ACXL). The surface tension test confirmed that unmodified and modified OPI possessed surface activity and the equilibrium surface tensions decreased sharply with increasing protein concentration and leveled off to a constant value. The elastic modulus, G′, for the acetylated OPI suspension exhibited the highest value, while the G′ of the crosslinked (XLOPI) had the lowest. The plateau of G′, was 2961 Pa, 920 Pa, 223 Pa, 41 Pa, and 1.8 Pa for the ACOPI, ACXL, SOPI, and XL, respectively.     

Efficient immobilization of lipase from Candida rugosa by entrapment into poly(N-isopropylacrylamide-co-itaconic acid) hydrogels under mild conditions

Temperature and pH-sensitive hydrogels, based on N-isopropylacrylamide and itaconic acid, with varying comonomer ratios and crosslinking agent content, were prepared by free radical crosslinking copolymerization. The immobilization of lipase from Candida rugosa was carried out by post-loading entrapment method at different temperatures until equilibrium swelling was achieved. The effects of the hydrogel composition and the immobilization temperature on the hydrogel-binding capacity, immobilized lipase specific activity, as well as the enzyme leakage were studied. It was found that the NiPAAm/IA ratio, crosslinking agent concentration and the temperature at which the entrapment was performed significantly affected the hydrogel-binding capacity. The biocatalysts obtained by entrapment into hydrogel with the highest itaconic acid content at 5?°C exhibited both highest binding capacity and the highest specific activity, but appeared to be less suitable for repeated uses than those obtained at 25?°C.     

Traditional Rosa damascena flower harvesting practices evaluated through GC/MS metabolite profiling of flower volatiles

Industrial cultivation of Rosa damascena and rose oil production is a centuries-old industry based on well-established traditional hand-picking of rose flowers. Here the traditional rose harvesting practices were evaluated through GC/MS analysis of the volatile compounds accumulation in R. damascena flowers at eight different developmental stages, flower buds with arrested development and flowers collected at six daytime points related to flower picking. The accumulation of 80 out of 100 volatile compounds was significantly influenced by the stage of flower development while 62 out of 103 compounds were significantly influenced by the daytime period of flower collection. Principal component analysis showed close clustering of the flower developmental stages and daytime periods preferable for flower harvesting and production of high quality and quantity of rose oil. Taken together the obtained results provide further support to the currently applied traditional rose flower harvesting practices. The possible applications of more precise flower harvesting for fine modulation of rose oil composition and reduction levels of the unwanted compound methyl eugenol are discussed.