Pelargonic acid (PA) is commercially obtained by oxidative cleavage of fatty acid double bonds. Its esters are interesting compounds used to create bio-based products. An industrially relevant application of these compounds is in the field of solvent manufacturing and formulation of green lubricating oils. The physical-chemical and rheological properties of these esters are influenced by the structural features of the alcohol used as starting materials, such as chain length, number of unsaturation, and degree of branching. This work provides an in-depth study of the existing structure-properties relations for fatty acid alkyl esters obtained from PA and different alcohols [i.e., 2-ethylhexanol (EtHex), ethylene glycol, 1,3-propanediol, 1,4-butanediol, trimethylolpropane, and pentaerythritol]. The aim is to evaluate the use of the synthesized product for the formulation of bio-based lubricants. The chosen alcohols are frequently employed in the preparation of bio-based lubricants. In addition, most of them, such as EtHex and diols, can be derived from biomass sources, contributing to the sustainability of the obtained products. For comparison purposes, some of these alcohols were also used for the synthesis of the corresponding oleic acid esters, which were chosen as a benchmark due to their common use in the synthesis of bio-based lubricants. The influence of the structural factors on the viscosity, pour point (PP), and oxidation stability of the synthesized esters was highlighted by comparing the obtained results. Pelargonates showed lower viscosities and higher PPs than that of the oleates, but they present high stabilities to the oxidation due to the absence of unsaturation.

♦ Background: Anterior ischemic optic neuropathy (AION) is characterized by infarction of the optic nerve head due to hypoperfusion of the posterior ciliary arteries and causes sudden blindness in adults on chronic dialysis, but has rarely been described in children. Unlike adults, children do not have comorbidities related to aging.

Metakaolin-based geopolymers with different molar ratios of Si/Al were synthesized and utilized as an efficient adsorbent for the removal of methylene blue (MB) as a model cationic dye from aqueous solution. Various analytical techniques were employed to characterize the synthesized geopolymers. The influence of the main operation conditions on the adsorption kinetics of MB onto the geopolymer was examined under various operating conditions. Results showed a significant maximum MB adsorption capacity at the temperature of 30 °C for all four types of geopolymers studied (designated as A, B, C, and D) up to 35.3, 23.6, 25.5, and 19.0 mg g⁻¹, respectively. The corresponding order of Si/Al ratio was A < C < B < D. Adsorption kinetics was so fast and reached equilibrium in 10 min, and the experimental results were described using the adsorption dynamic intraparticle model (ADIM). The equilibrium data for MB removal was in agreement with the Langmuir isotherm.

Introduction: The aim of this work was to describe the optical coherence tomography (OCT) angiography (OCTA) features in paediatric Leber-Coats disease. Methods: Three children presenting with unilateral, clinically active Leber-Coats disease were evaluated using spectral domain OCT and OCTA. OCT angiograms were analysed and compared with the current literature. Results: All 3 OCT angiograms showed that the vessels had lost most of their collateral branches and presented many loops. The capillaries were rarefied and anomalies in vessel size, vasodilatation, and macroaneurysms were evident. Conclusion: This is the first case series of OCTA performed in children with Leber-Coats disease. OCTA is a non-invasive and non-contact technique, which can be considered of fundamental importance for the diagnosis, clinical management, and follow-up of the disease.