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In the current study, the effects of cement or lime content, fibre content, partial cement or lime replacement with zeolite and curing time on the Unconfined Compressive Strength (UCS) of sand have been investigated. The results reveal that increasing cement or lime content increases Maximum Dry Density (MDD) and Optimum Water Content (OMC). However, increasing zeolite replacement percentage decreases MDD and OMC. Increasing the fibre content from 0 to 4% reduces the MDD and increases OMC. The optimum combination of the stabiliser and fibre has been derived from an array of tests. Results comparison shows the 0.5% fibre content and 8% stabiliser results in maximum effect. Also, the optimum percentage of 80% replacement of lime and 30% and 40% replacement of the cement with zeolite leads to the maximum UCS. Observing failure patterns demonstrates the influential performance of fibre content such as controlling the crack length and brittle behaviour. Moreover, SEM analysis was conducted to compare the microscale behaviour. [ABSTRACT FROM AUTHOR]

Modified TiO2 nanoparticles were successfully embedded into Pebax-1657 as a polymer matrix. The resulting mixed-matrix membranes are highly efficient for CO2 removal especially at high pressures. Nanofiller grafting with 3-aminopropyl-diethoxymethylsilane (silane agent) and surface modification with carboxymethyl chitosan led to Pebax-modified-TiO2 composite membranes with 50–60% increase in CO2 permeability and 30–33% in CO2/N2 selectivity compared to the pristine Pebax. The performance of the nanocomposite membranes is favorably above the 2008 Robeson upper bound. Stability analyses of the prepared membranes showed acceptable durability of the membranes in permeation experiments. Characterization techniques such as FT-IR, DSC, TGA, and SEM showed the compatibility of the nanoparticles and the polymer, better thermal stability of the nanocomposite membranes, and satisfactory dispersion of nanofillers into the polymer. [ABSTRACT FROM AUTHOR]

The title complex compound, [Ir(C 27 H 29 N 5 )Cl(C 10 H 8 N 2 )](CF 3 SO 3 ) 2 , was synthesized for a study of iridium(III)/periodate redox systems in water. The coordination geometry of the complex can be best described as distorted octa-hedral, with an r.m.s. deviation of 8.8 (8)% from ideal octa-hedral rectangular geometry. In the crystal, C-H⋯O and C-H⋯F inter-actions between the complex cation and the tri-fluoro-methane-sulfonate anions are observed, as well as a C-H⋯Cl inter-molecular inter-action between neighboring complex cations. In addition, the benzimidazole ring systems display parallel-displaced π-π stacking with centroid-centroid distances of 3.585 (3)-3.907 (3) Å. One of the two tri-fluoro-methane-sulfonate anions is disordered over two orientations with an occupancy ratio of 0.582 (6):0.418 (6). The title complex was characterized using FT-IR, cyclic voltammetry/rotating disc electrode polarography, fluorescence spectrometry, high resolution mass spectrometry, CHN elemental analysis and 1 H NMR spectroscopy.