Two vacuum residues were delivered from two different petroleum refineries, one from Suez Petroleum Company and the second from Alexandria Petroleum Company. Two heavy residues were subjected to solvent extraction using n-pentane, n-heptane, and ethyl acetate. The studied residues were fractionated into their components. Infrared spectroscopy was applied to study the distribution of functional groups contained in samples and their components. Some ratios calculated from the peak heights of selected infrared bands allow for a better comparison. The UV-Vis spectroscopic technique was applied to the aromatic fraction to determine how much mono-, di-, and polyaromatics are present in the aromatic fraction. The monoaromatics represent the lowest constituent among the aromatics present, whereas the polyaromatics and diaromatics are predominantly present and form the major constituent.
Conducting polymers have great attention due to their electrical activity in π-electrons conjugation over backbone of the polymeric chain. These properties make them attractive for enormous applications. On that account, we prepared polyanisidines (PAs) derivatives ( ortho, meta, and para) by chemical oxidation process using ammonium peroxydisulfate as an initiator. The prepared PAs were characterized using various techniques. Moreover, conductivity measurements of PA derivatives showed that the ortho-derivative gave the highest value. The prepared PAs were investigated as photostabilizers for poly(vinyl chloride) (PVC) films. Different PVC films were prepared in the absence and the presence of PA derivatives and they were exposed to ultraviolet (UV) irradiation for 30 days. The gel weight % for irradiated PVC films was followed as a function of irradiation time. The results revealed that the blank PVC film (free PA derivatives) was completely degraded reaching 100% gel content. PVC films contain PA derivatives showed higher photostability than PVC blank film. A comparison between the investigated PA derivatives as UV stabilizers and Chimassorb commercial UV absorber was also investigated. PA derivatives showed better efficiency as UV stabilizers than the commercial one till 288 h of UV irradiation.
Cardiac and ocular manifestations were evaluated in 21 patients clinically suspected of mucopolysaccharidosis. After electrophoresis analysis of urinary glycoaminoglycans, 3 patients were excluded because their results did not correlate with any known type of mucopolysaccharidosis. Echocardiography revealed abnormal findings in 11 patients [61.1%]. The mitral valve was the most commonly affected valve; 7 patients [38.9%] had thickened mitral valve and 6 had mitral regurge. Corneal opacities were found in 3 patients [16.7%] and progressive increase in intraocular pressure in 1 patient [5.6%], while fundus examination showed early optic atrophy in 1 patient [5.6%] and bilateral papilloedema in 2 patients [11.1%].
Two vacuum residues were delivered from two different petroleum refineries, one from Suez Petroleum Company and the second from Alexandria Petroleum Company. They were subjected to solvent extraction using n-pentane, n-heptane, and ethyl acetate. The process of solvent extraction aims to separate maltenes and asphaltenes. The maltenes were further subjected to liquid chromatography (column chromatograph) in order to separate them into saturates and aromatics (mono-, di-, and poly-) and resins. The saturates that were separated from the maltenes of the two vacuum residues with different solvents were studied by gas chromatography in order to determine how much n-paraffins and cyclo-paraffins they contained.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.