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In this study, we aim to quantify coating uniformity and correlate fluorescence intensity to drug loading for drug-coated angioplasty balloons (DCB) coated with 5, 10, 15, or 20 layers of poly(lactic-co-glycolic acid) nanoparticles (NPs) entrapped with quercetin. Uniformity was quantified from histograms and horizontal line profiles of microscopic fluorescent images acquired with sample specific parameters, and cracks in the coating were measured and counted. The fluorescence of images acquired with global parameters was correlated with quercetin loading measured via gravimetric/HPLC analysis. More layers on DCBs may be associated with less uniform coatings, as indicated by differences in histogram standard deviations. The line profile percent deviation from average for each sample was <20%. Cracks were present on all balloons, but their length was not significantly different between samples. The 5-layer DCBs had the fewest cracks, whereas the 15-layer DCBs had the most cracks. A strong positive correlation (R = 0.896) was identified between fluorescence intensity and drug loading. A relationship between the number of layers and coating uniformity seems to exist, but further investigations are required for confirmation. Fluorescence intensity appears to strongly predict drug loading, demonstrating that fluorescent imaging may be a viable alternative to drug release studies. [ABSTRACT FROM AUTHOR]

Amphiphilic copolymers were synthesized by grafting poly(lactic-coglycolic) acid with two lignin types: alkaline lignin and lignosulfonate. An interphase formation technique was used to produce films based on the copolymers. Films presented one side as being more hydrophobic (Oside) and smoother, and the second side more polar and with an uneven surface (W-side). Contact angle of water on the W-side was lower than the O-side corresponding to a higher lignin content and influenced by the lignin type (alkaline < lignosulfonate) and lignin: PLGA ratio. X-ray photoelectric spectroscopy analysis showed higher percentages of sulfur on the W-side, which supports a preferential partitioning of the lignin. Tensile testing demonstrated the significant impact of lignin type on the mechanical properties of the films. Alkaline films showed a higher maximum strength, a higher stiffness, and a higher tensile strength at the elastic limit compared to lignosulfonate films. However, for lignosulfonate films, ductility at break point was 4-fold higher than that of alkaline films. [ABSTRACT FROM AUTHOR]

Willow wood presents a real interest for biomass pyrolysis due to its fast growth, renewability, and high energy density. Following the pyrolysis of willow wood in an inert atmosphere, a multi-fuel gaseous mixture was obtained, with the following composition (by volume): 38.20% CO/21.87% H2/17.44% CH4/1.15% O2/17.15% CO2/4.19% N2. The propagation of laminar premixed flames in these multifuel mixtures with air was investigated numerically for initial temperatures from 298 to 500 K, initial pressures from 1 to 20 bar, and fuel equivalence ratios between 0.60 and 2.00. The combustion of these gaseous mixtures as free laminar premixed flames was simulated by means of the INSFLA package and an extended reaction mechanism with 592 elementary reactions and 53 species. The modelling of the gas-phase combustion delivered several important parameters: the laminar burning velocities, Su, the maximum flame temperatures, Tfl,max, the flame front thicknesses, dfl, and the peak concentrations of the main reaction intermediates. The obtained parameters, discussed in correlation with the initial pressure and temperature, afforded the determination of the overall activation parameters of multifuel oxidation with air. [ABSTRACT FROM AUTHOR]

Due to the ever-increasing consumption of fossil fuels, their impact on the environment, and the volatility of the market, it is advisable to use biofuels that can be produced locally from renewable sources, which supports the local economy, agriculture, and related processing industries. This article deals with how to improve the flow properties and pour point of biofuels for diesel engines. For the experiment, biodiesels in the form of rapeseed methyl ester (RME) and methyl ester made from waste animal fats and tallow (WAFME) were used. The pour point, viscosity, and density of WAFME were improved by mixing with RME and/or by adding bio-alcohols (alcohols produced from biomass, e.g., lignocellulosic). All used biofuels were classified as 2nd generation biofuels. The flow properties of the mixtures were monitored and subsequently modelled at temperatures from -10 to 60 °C. The addition of bio-alcohol had a statistically significant effect on the decrease in the viscosity and pour point of ternary blends (p < 0.05). Mathematical models of the dependence of kinematic viscosity on the temperature of mixtures (power law, exponential, Arrhenius, and Vogel) were created. [ABSTRACT FROM AUTHOR]