Cost efficiency of Yemen Islamic banks: An inefficiency effects approach (2002-2014)

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Impact of ZnMn2O4/CdS nanocomposite on the structural, optical and dielectric characteristics of PMMA/PEO blend

Herein, polymethyl methacrylate (PMMA)/ polyethylene oxide (PEO) blend doped with nanocomposite (1 − x) ZnMn2O4/xCdS samples were prepared through two steps, the first comprising nanocomposite (1 − x) ZnMn2O4/xCdS samples synthesizing, while the second was the incorporation of nanocomposites into the blend matrix, and finally the films were obtained through the casting solution method. Various techniques, such as X-ray diffraction, scanning electron microscopy, diffused reflection and impedance spectroscopy were used to determine the change in the PMMA/PEO structure after the inclusion of the nanocomposites. The direct and indirect optical bandgap values for the PMMA/PEO blend decreased from 5.04 and 4.8 eV to 4.99 and 4.7 eV, respectively, as the blend doped with (1 − x) ZnMn2O4/xCdS samples. At 600 nm, the refractive index of the blend was raised from 1.37 to 1.53 as it doped with 0.9 ZnMn2O4/0.1CdS sample. The linear and nonlinear optical parameters grow with the insertion of (1-x)ZnMn2O4/xCdS nanocomposites into the PMMA/PEO blend. Variation of CdS in the doped nanocomposites affects slightly the linear and nonlinear optical parameters of the host blend. Blend containing 10 % CdS has the highest linear and nonlinear optical parameters as compared with other doped blends. All of the blends exhibited different shades of blue color, except for the blend that contained 10 % CdS, which displayed a violet color. The effect of doping on the dielectric properties of different blends was also explored. Blend with 20 % CdS has the highest energy density. This improvement implies the use of prepared blends in different optoelectronic, photocatalytic and storage device applications

Optical and structure properties of CH

Methylammonium lead iodide doped with cesium (MA1–xCsxPbI3, x = 0, 0.03, 0.05, 0.1) thin films were prepared with and without chlorobenzene (CB). X-ray diffraction analysis applying the Rietveld refinement method is carried out, and the effect of Cs and CB on the lattice parameters, crystallite size, lattice microstrain, and dislocation density of the formed films is examined. SEM images with different magnifications are used to investigate the films' morphology and homogeneity. Adding CB reduced the number of pinholes and the grain size in the formed films. The UV-Vis-NIR spectroscopy technique was used to investigate the transmittance, reflectance, and absorbance spectra for Cs doped MAPbI3 with and without CB. In general, for Cs doped films, adding CB increases the film transmittance. The refractive index of 3% Cs doped film has the highest value among the films without CB. The optical bandgap, refractive index, and optical conductivity for films with CB are higher than those without CB for all doping Cs values. The influence of Cs doping and CB addition on the photoluminescence (PL) emitted spectra was studied using a PL set-up with a laser source of 532 nm