A Comparative Analysis of Vanadyl Porphyrins Isolated from Resins of Heavy Oils with High and Low Vanadium Content

The composition of purified vanadyl porphyrins recovered from the resins of heavy oils possessing high and low vanadium contents was investigated. Vanadium content in the resins of the heavy oils under study differs by a factor of ca. 15. To recover and purify vanadyl porphyrins from the resins, extraction by N,N–dimethylformamide (DMF) with subsequent two-stage column chromatography on silica gel and sulfocationite were employed. The change of structural-group composition and content of vanadyl porphyrins in the products obtained at each stage was evaluated using Fourier IR and UV-Vis spectroscopy. Analysis of the purified vanadyl porphyrins using MALDI mass spectrometry determined distribution of their most abundant types (etio- and DPEP) and identified C27–C39 homologs for the resins possessing high vanadium content and C28–C39 homologs for the resins with low vanadium content.

Production of Bitumen Modified with Low-Molecular Organic Compounds from Petroleum Residues. 3. Tar Modified with Formaldehyde

The chemical modification of tar with formaldehyde as 37% aqueous solutionhas been studied in the presence of the catalysts. Hydrochloric acid, sulfuric acid, sodium hydroxide and acid tar were used as the catalysts. The effect of the catalyst nature and amount, as well as temperature, process time and initial components ratio on the softening point, penetration, brittle point and adhesion to crushed stone has been determined. The structure of the modified tars was confirmed by IR spectroscopy. The structural-group composition was determined. Arene-formaldehyde resins have been synthesized on the basis of toluene and modified tars using hydrochloric acid as a catalyst. The synthesized resins were characterized using IR spectroscopy. The chemistry of the tar modification with formaldehyde has been proposed.

Drawingvoice 2.0: classroom joint designing and Facebook interactions to develop reflexivity and awareness

Drawingvoice 2.0 is an instructional method of collaborative pencil and paper drawing to use in the school classroom, followed by Facebook interaction on the drawing produced in class. It is based on a participatory and meta reflective approach, explicitly aimed at deconstructing, negotiating, and reconstructing the meaning that students attribute to themselves regarding their professional expectations and educational pathways. In particular, the collaborative pencil and paper drawing allows for the student’s emotional symbolisation processes underlying their educational pathway. Drawingvoice 2.0 induces a multidimensional cognitive and meta-cognitive process further supported by the following interaction on Facebook. Therefore, the World Wide Web is the added resource for sharing and deepening the classmates’ discussion. Finally, Drawingvoice 2.0 supported structural group interaction and was an important supportive and instructional method to bring about transformational and developmental training practices. As the main result, in our experience, psychology students increased their reflectivity about their strengths and threats in being psychologists within their cultural contexts and potential positive resources underlying their choice. Drawingvoice 2.0 thus enhanced their self-awareness about the lights and shadows of their training and future professional career.

Transformation of Resinous Components of the Ashalcha Field Oil during Catalytic Aquathermolysis in the Presence of a Cobalt-Containing Catalyst Precursor

The aim of this work was to study the fractional composition of super-viscous oil resins from the Ashalcha field, as well as the catalytic aquathermolysis product in the presence of a cobalt-containing catalyst precursor and a hydrogen donor. The study was conducted at various durations of thermal steam exposure. In this regard, the work enabled the identification of the distribution of resin fractions. These fractions, obtained by liquid adsorption chromatography, were extracted with individual solvents and their binary mixtures in various ratios. The results of MALDI spectroscopy revealed a decrease in the molecular mass of all resin fractions after catalytic treatment, mainly with a hydrogen donor. However, the elemental analysis data indicated a decrease in the H/C ratio for resin fractions as a result of removing alkyl substituents in resins and asphaltenes. Moreover, the data of 1H NMR spectroscopy of resin fractions indicated an increase in the aliphatic hydrogen index during catalytic aquathermolysis at the high molecular parts of the resins R3 and R4. Finally, a structural group analysis was carried out in this study, and hypothetical structures of the initial oil resin molecules and aquathermolysis products were constructed as well.

The Scalar Curvature of a Riemannian Almost Paracomplex Manifold and Its Conformal Transformations

A Riemannian almost paracomplex manifold is a 2n-dimensional Riemannian manifold (M,g), whose structural group O(2n,R) is reduced to the form O(n,R)×O(n,R). We define the scalar curvature π of this manifold and consider relationships between π and the scalar curvature s of the metric g and its conformal transformations.

A WOODEN-COLUMNED MOSQUE FROM ANATOLIA. BEYŞEHİR EŞREFOĞLU MOSQUE

Wooden-columned mosques constitute a major structural group in Turkish mosque architecture. Inspired by the abundance of forestation in the region in which they were built, the mosques that made use of wood boasted of rich architectural ornamentation. It is the aim of this study to offer a presentation of Beyşehir Eşrefoğlu Mosque, one of the wooden-columned mosques that were widely constructed in the Anatolian Selçuk Era, taking their place in Anatolian Turko-Islamic architecture. A product of the local master builders of its time, the structure was included in UNESCO’s List of Provisional World Heritage Sites. In this context, the paper will describe the characteristics and elements of the layout of the Beyşehir Eşrefoğlu Mosque, its structural system, roof structure, and the distinctive features of the materials and adornments used.

Study of oxygen compounds of acid character of Garbi Absheron field oil

The paper presents the results of fraction and structural-group composition of acids and phenols of Garbi Absheron field oil. Studied oil is heavy, tarry, low paraffinic. The acids and phenols have been purified from the oil with their differentiation on the free and associated (in the form of compound esters) forms. Free acids and phenols were purified from the oil via alkali extraction. Their associated forms were purified after saponification of the oil released from the samples. To study the structure-group content of acids and phenols, proton-magnetic resonance spectroscopy method was used. Obtained results showed that acidic oxygen-containing compounds in Garbi Absheron field oil predominantly consist of associated acids and phenols in the form of compound esters. Middle molecules of these phenols contain condensed naphtenic-aromatic cycles, the acids by their structure belong to the derivatives of hydrocarbons of paraffin series of CH3 residual-substitutes.

A Structure Hierarchy for the Aluminofluoride Minerals

ABSTRACT The structure hierarchy hypothesis states that structures may be ordered hierarchically according to the polymerization of coordination polyhedra of higher bond-valence, and such hierarchies are useful in understanding the general compositional, structural, and paragenetic variations within the structural group of interest. Here we develop a structure hierarchy for the aluminofluoride minerals based on the polymerization of the dominant (AlΦ6) octahedra and their linkage with other strongly bonded complex anionic groups. The minerals are divided first into the following categories: (1) simple aluminofluorides and (2) compound aluminofluorides containing other oxyanions. The minerals are then ordered according to the polymerization of the constituent polyhedra into a coherent structural hierarchy. The chemical composition and crystal-chemical details of the ions of the interstitial complex are a collective function of the Lewis acidity of the interstitial cations; the presence of interstitial anions, both simple [F–, (OH)–] and complex [(SO4)2–]; self-polymerization of the (AlF6)3– octahedra; and polymerization with both Mg(F,OH)6 octahedra and other complex anions: (SO4)2–, (PO4)3–, (CO3)2–.