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This study explores a simple method of fabricating hybrid supercapacitor electrodes, which could potentially broaden the application of this technology. The method involves electrospinning a uniform solution of Matrimid/Metal−Organic Polyhedra 18 (MOP−18) followed by carbonization at a relatively low temperature of 700 °C in air, rather than in an inert atmosphere, to create free−standing, redox−active hybrid supercapacitor electrodes. Additionally, the synthesis procedure requires no stabilization or activation steps, which enhances the cost effectiveness of the synthesized electrode materials. The resulting C/CuO composite was used as the working electrode, with a polyacrylonitrile (PAN)/Poly(methyl methacrylate) (PMMA) carbon nanofiber (CNF) electrode as the counter and 6 M KOH as the electrolyte in a T−cell configuration. The cell performance and redox activity were evaluated using cyclic voltammetry (CV), galvanostatic charge–discharge (GCD), electrochemical impedance spectroscopy (EIS) and cycling stability tests. Additionally, the physical and chemical structures of the electrode materials were assessed using X−ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron spectroscopy (TEM), X−ray diffractometry (PXRD), surface area analysis and other characterization techniques. The electrode material demonstrated a specific capacitance of up to 206 F/g. Supercapacitors utilizing this material display an energy density of 10.3 Wh/kg (active material) at a current density of 1 A/g in electrochemical testing. [ABSTRACT FROM AUTHOR]

Gas separation for industrial, energy, and environmental applications requires low energy consumption and small footprint technology to minimize operating and capital costs for the processing of large volumes of gases. Among the separation methods currently being used, like distillation, amine scrubbing, and pressure and temperature swing adsorption, membrane-based gas separation has the potential to meet these demands. The key component, the membrane, must then be engineered to allow for high gas flux, high selectivity, and chemical and mechanical stability at the operating conditions of feed composition, pressure, and temperature. Among the new type of membranes studied that show promising results are the inorganic-based and the metal-organic framework-based mixed-matrix membranes (MOF-MMMs). A MOF is a unique material that offers the possibility of tuning the porosity of a membrane by introducing diffusional channels and forming a compatible interface with the polymer. This review details the origins of these membranes and their evolution since the first inorganic/polymer and MOF/polymer MMMs were reported in the open literature. The most significant advancements made in terms of materials, properties, and testing conditions are described in a chronological fashion. [ABSTRACT FROM AUTHOR]

This publication proposes a novel approach to automatically colour and texture a given terrain mesh in real time. Through the use of weighting rules, a simple syntax allows for the generation of texture and colour values based on the elevation and angle of a given vertex. It is through this combination of elevation and angle that complex features such as ridges, hills and mountains can be described, with the mesh coloured and textured accordingly. The implementation of the approach is done entirely on the GPU using 2D lookup textures, delivering a great performance increase over typical approaches that pass colour and weighting information in the fragment shader. In fact, the rule set is abstracted enough to be used in conjunction with any colouring/texturing approach that uses weighting values to dictate which surfaces are depicted on the mesh. [ABSTRACT FROM AUTHOR]

Abstract: A microporous metal-organic framework Cu–4,4′-bipyridine–hexafluorosilicate (Cu–BPY–HFS), having a surface area of 2000m2/g, was combined with Matrimid® polymer to form free standing films. The permeability properties of Cu–BPY–HFS–Matrimid® mixed-matrix membranes were tested for the pure gases H2, N2, O2, CH4, and CO2 and the gas mixtures CO2/CH4, H2/CO2 and CH4/N2. The ideal selectivity of CH4/N2 increased from 0.95 to 1.21, which suggests that Cu–BPY–HFS has a strong affinity towards CH4 and favors its permeation. The higher solubility of CH4 in the membranes leads to higher selectivity for CH4/N2. The enhanced CH4 transport is also apparent in the case of ideal selectivity for CO2/CH4 and H2/CH4. For CH4/N2 gas mixtures, the selectivity increased from 0.95 to 1.7. The Cu–BPY–HFS''s affinity towards CH4, and its large surface area increased the solubility of CH4 in the mixed-matrix membranes, which led to higher selectivity towards CH4. [Copyright &y& Elsevier]

Abstract: Exfoliated graphite nanoplatelet (xGnP) and V2O5 nanotube (VNT) composite electrodes were fabricated and tested as electrodes for supercapacitors. Enhancement of the electrochemical performance of the composite over its component materials was demonstrated using cyclic voltammetry (CV), constant current charge/discharge testing and electrochemical impedance spectroscopy in aqueous and organic electrolytes. The calculated specific capacitance of the composite was 35Fg−1 in the aqueous electrolyte and 226Fg−1 in the organic electrolyte at a scan rate of 10mVs−1 using a three-electrode system. Asymmetric coin cell devices were fabricated using activated carbon cloth as the positive electrode and xGnP–VNT composite as the negative electrode. The energy and power densities in 1M LiTFSI were 28Whkg−1 and 303Wkg−1, respectively, at a discharge current density of 250mAg−1. [Copyright &y& Elsevier]

Abstract: Mixed-matrix membranes were prepared from Matrimid® and mesoporous ZSM-5 nanoparticles containing crystalline ZSM-5. The ideal selectivity for H2/N2 separation increased from 79.6 for pure Matrimid® to 143 at 10% loading, while the selectivity of O2/N2 increased from 6.6 for pure Matrimid® to 10.4 at 20% loading. The ideal H2/CH4 separation factor increased from 83.3 to 169 at 20% loading. The results suggest that the mesopores of the ZSM-5 material provide good contact between the nanoparticles and the polymer, since the polymer chains can penetrate into the mesopores. The micropores of ZSM-5 crystals provide size and shape selectivity. [Copyright &y& Elsevier]