Experimental and field applications of nanotechnology for enhanced oil recovery purposes: A review

Pyrochlores belong to a numerous family of crystalline materials with a rich variety of technologically important functional properties and developed structural diversity of possible transformation...

Structural Diversity of Ordered Pyrochlores

A new member of fluorooxoborates, Li2Na0.9K0.1B5O8F2, was obtained in the sealed system, and single-crystal X-ray diffraction was used to determine its structure. It contains a three-dimensional framework stacking of [B5O8F2]3– layers extending into the ac plane. Detailed structural comparisons among all of the fluorine-containing alkali-metal borates suggest that the [B5O8F2]3– layer composed of the new fundamental building blocks B5O10F2 represents a new structure type of fluorooxoborate. The IR spectrum verifies its structural validity. The deep-ultraviolet spectral measurement shows that it has no obvious absorption in the range of 180–300 nm, and its cutoff edge is under 180 nm. In addition, theoretical calculations were done to help us understand its electronic structure and optical properties.

A Member of Fluorooxoborates: Li2Na0.9K0.1B5O8F2 with the Fundamental Building Block B5O10F2 and a Short Cutoff Edge.

Structure analysis and electronic properties of ATe4+0.5Te6+1.5-xM6+xO6 (A=Rb, Cs, M6+=Mo, W) solid solutions with β-pyrochlore structure

Membranes are a promising technology for bulk CO2 separation from natural gas mixtures due to their numerous advantages. Despite the numerous fundamental studies on creating better quality membrane efficiency, scaling up the research work for field testing requires huge efforts. The challenge is to ensure the stability of the membrane throughout the operation while maintaining its high performance. This review addresses the key challenges in the application of polymeric technology for CO2 separation, focusing on plasticization and aging. A brief introduction to the properties and limitations of the current commercial polymeric membrane is first deliberated. The effect of each plasticizer component in natural gas towards membrane performance and the relationship between operating conditions and the membrane efficiency are discussed in this review. The recent technological advancements and techniques to overcome the plasticization and aging issues covering polymer modification, high free-volume polymers, polymer blending and facilitated transport membranes (FTMs) have been highlighted. We also give our perspectives on a few main features of research related to polymeric membranes and the way forwards. Upcoming research must emphasize mixed gas with CO2 including minor condensable contaminants as per real natural gas, to determine the competitive sorption effect on CO2 permeability and membrane selectivity. The effects of pore blocking, plasticization and aging should be given particular attention to cater for large-scale applications.

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Recent Advances of Polymeric Membranes in Tackling Plasticization and Aging for Practical Industrial CO2/CH4 Applications—A Review

Regulating of MnO2 photocatalytic activity in degradation of organic dyes by polymorphic engineering

Cod Gelatin as an Alternative to Cod Collagen in Hybrid Materials for Regenerative Medicine

The role of surface and electronic structure features of the CsTeMoO6 β-pyrochlore compound during the photooxidation dyes process

Radical polymerization of methyl methacrylate in an aqueous emulsion was carried out using the complex oxide RbTe15W05O6 as a photoinitiator under visible light irradiation with λ = 400–700 nm Study of the polymerization process and reaction products using methods of physical and chemical analysis (GPC, IR, NMR, etc) has shown that there are several directions of monomer transformations at the same time Polymethyl methacrylate with Mn ~ 140–145 kDa, produced in the organic phase, is a result of polymerization initiation by a hydroxyl radical formed due to complex transformations of electron–hole pairs during photocatalyst irradiation Moreover, the interaction of the hydroxyl radical with OH-groups on the complex oxide RbTe15W05O6 surface and the subsequent formation of oxygen-centered radicals lead to grafting polymer macromolecules on the photocatalyst surface In addition, methyl methacrylate is able to oxidize to a cyclic dimer with terminal double bonds and form a polymer with cyclic dimer links due to coordination by double bonds on the RbTe15W05O6 surface The high activity of the hydroxyl radical allows to obtain the graft copolymer PMMA-pectin by grafting the polymer product on the surface of the natural polymer-pectin Comparison of the sponge morphology of the graft copolymer PMMA-pectin and the initial pectin samples using the scanning electron microscopy has shown a noticeable difference in their structural and topological organization It is especially interesting in terms of studying the properties of the graft copolymer as a material for the scaffolds

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Features of Polymerization of Methyl Methacrylate using a Photocatalyst—the Complex Oxide RbTe1.5W0.5O6

Photocatalytic oxidative desulfurization has attracted much attention in recent years due to the continuous tightening of the sulfur content requirements in motor fuels and the disadvantages of the industrial hydrodesulfurization process. This work is devoted to the investigation of the photocatalytic activity of Bi2WxMo1−xO6 solid solutions (x = 1, 0.75, 0.5, 0.25, 0) in the oxidative desulfurization of hydrocarbons under visible light irradiation using hydrogen peroxide as an oxidant. The synthesized photocatalysts were characterized in detail using XRD, SEM, EDS, low-temperature nitrogen adsorption–desorption, and DRS. It was shown that the use of solid solutions Bi2WxMo1−xO6 with x = 0.5–0.75 leads to the complete oxidation of organosulfur compounds to CO2 and H2O within 120 min. The high photocatalytic activity of solid solutions (x = 0.5–0.75) is attributed to their ability to absorb more visible light, the presence of the corner-shared [Mo/WO6] octahedral layers, which may promote the generation and separation of photogenerated charges, and the hierarchical 3D flower-like structure. The reaction mechanism of the desulfurization was also analyzed in this work.

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D.G. Fukina

Papers

Regulating of MnO2 photocatalytic activity in degradation of organic dyes by polymorphic engineering

Cod Gelatin as an Alternative to Cod Collagen in Hybrid Materials for Regenerative Medicine

The role of surface and electronic structure features of the CsTeMoO6 β-pyrochlore compound during the photooxidation dyes process

Features of Polymerization of Methyl Methacrylate using a Photocatalyst—the Complex Oxide RbTe1.5W0.5O6

Synthesis and Characterization of Bi2WxMo1−xO6 Solid Solutions and Their Application in Photocatalytic Desulfurization under Visible Light