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The influence of the size and oxidation state of Au nanoparticles (AuNPs) as electrocatalysts for the electro-oxidation of cellulose was studied. Carbon paper electrodes modified with AuNPs were used as the electrocatalysts for the electro-oxidation of cellulose dissolved in 1.3 m NaOH. The size and oxidation state of the AuNPs were determined by using SEM, TEM, and X-ray photoelectron spectroscopy. Both the size and the oxidation state of the AuNPs were found to influence the electrocatalytic properties of the electrode, as studied by using cyclic voltammetry, square wave voltammetry, and electrochemical impedance spectroscopy. The carbon paper electrodes decorated with AuNPs (less than 25 nm) that consist of metallic Au gave rise to a significantly higher electrocatalytic activity than a bare polycrystalline Au electrode. [ABSTRACT FROM AUTHOR]

BACKGROUND Two types of bleaching earths used in the production of green diesel, namely, sepiolite and palygorskite, were characterized by various physico-chemical methods, such as nitrogen adsorption, Hg porosimetry, scanning electron microscopy, transmission electron microscopy, energy dispersive X-ray analysis, Fourier transfom infrared spectroscopy, pH of the clay slurry, thermogravimetrical analysis ( TGA) and X-ray diffraction analysis. The characteristics of fresh, spent and extracted bleaching earths were compared in the current study. RESULTS The results showed that particle sizes of the extracted adsorbents have decreased. Furthermore, some leaching of elements was confirmed by elemental analysis. A decrease in specific surface area of the adsorbents was observed thus compromising the economical feasibility of the reuse of these clays. TGA results showed that the oil content in spent sepiolite and palygorskite, which could be extracted was 35% and 12%, respectively. Extraction efficiencies were affected by the specific surface area of the clay. CONCLUSIONS Structural characterization of extracted bleaching earths showed that some changes occurred for sepiolite and palygorskite during bleaching and extraction in addition to decrease in their particle sizes. The specific surface areas of the extracted bleaching earths decreased substantially compared with those determined for fresh bleaching earths. This result indicates that reuse of spent, extracted bleaching earths might not be economically feasible. © 2014 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Context: Electrospraying was used in drug particle production. Objective: The aim of the research was to evaluate the possibilities to produce drug particles with desired pharmaceutical properties by electrospraying. In particular, the effect of drying pressure on particle properties was studied. Materials and methods: A poorly water soluble model drug (budesonide) was dissolved in chloroform, and the solution was atomized by electrospraying. Following this, the charged droplets were neutralized and dried in a drying chamber. The pressure in the drying chamber was varied. The dried particles were collected and analyzed. Results: The pressure reduction had a slight impact on particle size distribution. The particles produced in reduced pressure turned out to be notably more porous than the particles produced in atmospheric pressure. The pressure reduction also affects the degree of crystallinity of the product. The dissolution of the particles produced in reduced pressures was faster to a certain extent than that of the particles produced in atmospheric pressure. Discussion and conclusions: A setup for electrospraying materials in a reduced pressure was presented. The pressure reduction had a notable impact on particle morphology. The possibilities to tailor the particle properties during electrospraying were studied. [ABSTRACT FROM AUTHOR]