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Using the solution casting procedure, poly (vinyl alcohol)/carboxymethyl cellulose/polypyrene/milled multiwall carbon nanotubes, PVA/CMC/PPy/x wt% milled MWCNTs blended polymers were formed. X-ray diffraction and scanning electron microscopy were employed to inspect the structure and morphology of the resulted blends. The lowest direct and indirect optical band gaps are (5, 4.3) eV and (4.37, 3.38) eV, respectively, achieved when the MWCNTs content in the doped blend was 0.25 wt %. By incorporating varying quantities of milled MWCNTs into the PVA/CMC/PPy blended polymer, consistent enhancements were observed in the optical dielectric constant and optical conductivity values. The blend with 0.25 wt% MWCNTs exhibited the maximum values of refractive index. The maximum electric dielectric constant and energy density values were attained as x = 0.15. The temperature impacted the dielectric constants and energy storage values. All blends fit with the CBH model. The impact of MWCNTs doping level and the temperature on the impedance spectroscopy and electric modulus of the host blend was explored. The sample with x = 0.15 has the smallest relaxation time. The impact of MWCNTs doping level on the dc conductivity, activation energy and conductivity mechanism of the host blend was explored. The doped blends with x = 0.15 is viable materials for energy storage purposes.

Polyvinyl alcohol (PVA) and carboxymethyl cellulose (CMC) have been used as polymeric matrices to create polymeric nanocomposite films that contain polypyrrole (PPY) and melanin as fillers. The structure of the PVA/CMC/PPy/x wt % melanin blends was analyzed using the X-ray diffraction technique. The scanning electron microscopy technique was used to investigate the morphologies of the blends. The highest absorbance and reflectance spectra were observed when the melanin content reached 0.25 and 0.2 % wt %, respectively. The smallest direct and indirect optical band gaps are (4.91, 4.44) eV and (4.22, 3.79, 2.34) eV, respectively, achieved when the melanin content was 0.25 wt%. The blend doped with 0.15 wt% PANi yielded the highest refractive index values (1.396 at λ = 600 nm). The optical dielectric constant values of the blends exhibited irregular improvement when the PVA/CMC/PPy blended polymer was filled with varying quantities of melanin. The blend doped with 0.15 wt% melanin exhibits the highest optical conductivity values in the visible range. The blend of PVA/CMC/PPy with a melanin concentration of 0.15 or 0.2 wt% demonstrated the highest nonlinear optical parameters. The blend of PVA/CMC/PPy with a melanin concentration of 0.15 or 0.2 wt% demonstrated the highest nonlinear optical parameter. Based on the observed behavior of the I-V characteristic, the possibility of ohmic conduct ions or space charge limited conduct ions is ruled out in all blends. The charge transport mechanisms that take place in different blends under varying temperatures were examined. These outcomes suggest the opportunity of employing the created blended polymer in capacitive energy storage, optoelectronic devices and photocatalytic application.

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.

Polyvinyl alcohol (PVA)/0.25% polyaniline (PANi)/x wt % MWCNTs (x = 0, 0.1, 0.2, 0.5, 0.8, 1) blends were formed. The X-ray diffraction technique was used to investigate the formation of the different blends. The effects of the MWCNTs amounts on the optical parameters and emitted colours of the different blends were investigated. The optical band gaps for PVA/0.25% PANi/x wt % MWCNTs blends are 3.24, 3.13, 3.05, 2.99, 2.84, and 2.95 eV when the MWCNTs amounts in the blends become 0.0, 0.1, 0.2, 0.5, 0.8, and 1 wt %, respectively. The modifications in optical band gaps upon loading PVA/ PANi with MWCNTs indicated that the investigated blends are promising candidates for solar cell and photocatalysis applications. The DC conductivity exhibited a maximum value in the blend with 0.8 wt% MWCNTs. All blends have two activation energies. The influence of MWCNTs amounts on the dielectric constant, AC conductivity, impedance, electric modulus, characteristic frequency, and Nyquist plot of the different blends was examined.

Undoped and doped polyvinyl pyrrolidone/ carboxymethyl cellulose (PVP/CMC: 50/50%) blended polymers with melanin were formed. X-ray diffraction analysis confirmed the amorphous nature of all blends. Scanning electron microscopy results confirmed the smooth and homogeneous surface of the undoped and doped PVP/CMC blend with melanin. The optical parameters and fluorescence spectra of the PVP/CMC blend were investigated as functions of melanin content. The direct optical band gap (Eg) for the used melanin is 2.86 eV. The direct and indirect Eg values for the PVP/CMC blend are 5.1 and (4.9, 3.2) eV, respectively. The direct and indirect Eg values were reduced to (4.5, 3.23) and (2.2, 1.33) eV as the amount of melanin became 3 wt % in the doped blend. The effect of melanin doping on the dielectric constant, dielectric loss, AC conductivity, complex impedance, Nyquist plot of the complex impedance, and electric modulus of the PVP/CMC blend was also studied.

Nano Zn0.75−xMnxCd0.25S (x = 0, 0.05. 0.1, 0.15) doped PVA/PEG (7:3) polymer blend was fabricated . X-ray diffraction and scanning electron microscope techniques were used to investigate the possible formed phases in the nanofiller samples, and the formation of the blends. The changes in different optical parameters of PVA/PEG (7:3) upon doping with nano Zn0.75−xMnxCd0.25S were investigated . The optical bandgap of the polymer blend was decreased from 5.78 to 4.83 eV upon doping with Zn0.75Cd0.25S, and then increased a little by increasing the Mn content (x). The enhancement of nonlinear parameters as the blend doped especially with Zn0.75Cd0.25S nominated this blend to employ in various nonlinear optical and photonic fields. The fluorescence (FL) intensity was decreased as the PVA/PEG (7:3) blend was doped with nano Zn0.75−xMnxCd0.25S. The FL intensity of the doped blends was enhanced as the amount of Mn increased in the nanofiller. All samples emitted three violets and two blues colours.

Nano gadolinium oxide doped polyvinyl alcohol/polyethylene glycol blend (PVA/PEG) was prepared by sol–gel and casting methods. Rietveld refinement method was used for structural and microstructural investigation. The X-ray diffraction (XRD), scanning electron microscope (SEM) and Fourier transform infrared (FTIR) techniques were applied to study the formation of nano Gd2O3 doped PVA/PEG-blend. Differential scanning calorimetry technique (DSC) was utilized to investigate the glass transition, the melting and degradation temperatures of undoped and doped PVA/PEG blends. The melting temperature was increased slightly while the degradation temperature was reduced upon doping with nano Gd2O3. The behavior of the absorbance and other different optical parameters were studied in detail using UV-spectrophotometer. A variation in the optical bandgap of the PVA/PEG blend was observed while the values of refractive index and extinction coefficient were enhanced as the amount of Gd2O3 increased in the blend. The influence of nano Gd2O3 doping on the different dispersion parameters was examined using Wemple and DiDomenico approximation model. The nature of electronic transitions of different samples was examined by comparing the optical band gap obtained from Tauc’s relation and dielectric loss parameter.

Methylammonium lead iodide perovskites (MAPbI3) thin films were prepared by changing the molarity concentration of methylammonium iodide and lead iodide in the N,N- dimethylformamide solvent, with and without chlorobenzene (CB). Rietveld refinement analysis revealed that all prepared samples belong to tetragonal CH3NH3PbI3 phase (sp. gr. I4/mcm). The effect of MAPbI3 concentration on the lattice parameters, crystallite size, lattice microstrain and dislocation density of the prepared films with and without CB was investigated in detail. The FESEM images of perovskite films indicated the presence of pinholes in each sample, and the number of pinholes reduced as CB added to MAPbI3. Generally, the transmission and reflection spectra decreased as the amount of MAPbI3 increased in the films; also, both are reduced as CB added to films. The value of the reflectivity over measured wavelengths changed from about 1% to about 18% and 12% in the case of films without and with CB, respectively. Without CB, the highest absorbance intensity was obtained for 1.3 M films, while with CB the 1.5 M film has the highest absorbance. The number of bandgaps appeared in different samples depending on the concentration of MAPbI3 and CB. The refractive index at 500 nm for (1, 1.3 and 1.5 M) MAPbI3 films without CB are 1.6, 1.44, 1.43 and 1.31 respectively, where its value in the corresponding films with CB are 1.34, 1.3, 1.3 and 1.28, respectively. The effect of MAPbI3 concentration and the existence of CB during the film preparation on the extinction coefficient, refractive index, dielectric constant, the photoluminescence peak position, and PL intensity for the different films were explored.

The 70% polyvinyl alcohol/30% polyvinyl pyrrolidone (PVA/PVP) polymer blends, with different weight ratios of tetrapropylammonium iodide (TPAI) or tetrahexylammonium iodide (THAI) salt, were prepared using dimethyl sulfoxide (DMSO) as a solvent. The X-ray diffraction technique was used to trace the crystalline nature of the formed blends. The SEM and EDS techniques were applied to figure out the morphology of the blends. The variation in the FTIR vibrational bands was used to investigate the chemical composition and the effect of different salt doping on the functional groups of the host blend. The influence of the salt type (TPAI or THAI) and its ratio on the linear and nonlinear optical parameters for the doped blends were investigated in detail. Absorbance and reflectance are highly enhanced in the UV region reaching a maximum for the blend with 24% TPAI or THAI; so, it can be employed as shielding materials for UVA and UVB types. The direct (5.1 eV) and indirect (4.8 eV) optical bandgaps were reduced continuously to (3.52, 3.63 eV) and (3.45, 3.51 eV) while increasing the content of TPAI or THAI, respectively. The blend doped with 24% wt TPAI exhibited the highest refractive index (around 3.5 in 400–800 nm). The DC conductivity is affected by the content and type of salt, its dispersion, and blend-salt interaction. The activation energies of different blends were obtained by applying the Arrhenius formula.

The most efficient way to create novel materials that may be used in a variety of optoelectronic applications is thought to be doped mixed polymers with appropriate fillers. Undoped and doped PVC polymers with ZnS/Mn formed at different temperatures were fabricated using the casting method. The Rietveld method was used to discover the structure and microstructure of Zn0.95Mn0.05S prepared at T = 300, 400, and 500 °C. The distribution and existence of the nanofiller over the PVC matrix were determined via XRD, FTIR, EDS, and SEM techniques. The effect of the preparation temperatures of the ZnS/Mn nanofiller on the absorption, transmittance, reflectance, refractive index, extinction coefficient, dielectric constant, AC conductivity, electrical modulus, and DC conductivity activation energy data of the PVC polymer was studied using the diffused reflectance technique. Doping PVC with ZnS/Mn (prepared at 300 °C) lowered the direct and indirect optical band gaps from 5.4 and 4.52 eV to minimum values of 4.55 and 3.63 eV. The fluorescence intensity of pure PVC is greatly enhanced upon loading with ZnS/Mn. The PVC exhibited two near UV peaks, one violet and one blue color, while, in addition, the doped polymers exhibited green and orange colors. The corresponding CIE diagram for all the samples was also determined.

Nano (Mg1-xZnx)[Fe2-2x Mn2x]O4 solid solution was synthesized by a simple chemical route. The obtained samples were fully characterized utilizing Rietveld x-ray diffraction analysis, Fourier transform infrared (FTIR), high resolution transmission electron microscope (HRTEM), field emission scanning electron microscope (FESEM), diffuse UV absorbance, and photoluminescence (PL) techniques. Single phase cubic spinel structure MgFe2O4 was obtained confirming the formation of a solid solution. The influence of alloying on the cell parameter, cation distribution, crystallite size and particle morphology were determined. The bandgap reduced upon alloying and the PL intensity decreased as the amount of Zn and Mn increased in MgFe2O4 matrix. Measurements of photocatalytic degradation under UV light irradiation proved that alloying of magnesium ferrite with Zn and Mn ions greatly enhanced the photocatalytic activities, and optimum performance achieved with allying ratio x = 0.1. The enhancement in photocatalytic degradation was correlated with the characteristics changes.

The changes in the properties of the supercapacitor electrode material copper cobaltite, prepared by a simple hydrothermal procedure, were investigated upon doping with Mo with different ratios (CuCo1-xMoxO4, x = 0.0, 0.1, 0.2). The effect of doping on the structural, microstructural parameters, cation distribution was studied using Rietveld analysis for x-ray diffraction patterns. Results evidenced the incorporation of Mo6+ ions substitutionally for Co3+ ions, which is confirmed by the vibrational bands obtained from Fourier transform infrared spectrometry and by the vibrating sample magnetometer measurements. The particle morphology and size distribution of the samples were investigated using high-resolution transmission electron microscope (HRTEM) imaging. The influence of Mo-doping on the absorbance behavior of copper cobaltite was examined utilizing measured absorbance diffused spectra; the bandgap structure of doped samples was greatly affected. The changes that occurred in the optical band gap upon doping were explained using the Burstein–Moss shift effect. The photoluminescence intensity was affected by the amount of Mo doping. The samples emitted violet, blue, and yellow colors depending on the amount of doping.

The functional properties of (1-x)CuCo2O4/(x)CuS nanocomposite as an improved supercapacitor electrode have been investigated. X-ray diffraction with Rietveld analysis, HRTEM, FESEM, and FTIR techniques were employed for the full structural characterization of the nanocomposites. The particle size and morphology, the phase composition and percentage, the lattice parameters, the cation distribution and the crystallite size were accurately determined for the prepared samples. The variation of the bandgap of the phases developed with the alloying parameter (x) was studied utilizing the UV diffuse spectrum. All samples exhibited a blue shift except the sample with x = 0.25, it revealed a redshift. The photoluminescence intensity and the color emitted were affected by CuCo2O4 and CuS alloying. The preliminary test of cyclic voltammetry (CV) proved that alloying of CuS nanoparticles with CuCo2O4 enhanced the electrochemical activities, and optimum performance achieved with allying ratio x = 0.25.

The heterostructure nanocomposite (1-x)ZnFe2O4/xZnMn2O4 (x = 0, 0.5, 0.8, 1) samples were prepared using the sol–gel method. The structural parameters and the percentages of the phases formed were determined utilizing the Rietveld method. Beside the two phases formed ZnFe2O4 (ZFO) and ZnMn2O4 (ZMO), a minor phase ZnO (3%) was observed in the sample x = 0.5. Analysis revealed phase percentages for composite samples different from intended (x) values due to the exchange of cations between the phases formed. The effect of composition ratio (x), as well as the frequency and temperature on the dielectric constant, dielectric loss, impedance spectroscopy and complex electric modulus and ac conductivity, was examined. The degree of correlation in each sample was also determined. Different conductivity mechanisms are found for different samples and frequency ranges. The 0.2ZFO-0.8ZMO sample disclosed higher conductivity and higher dispersion relative to other samples. The effect of temperature on the Cole–Cole plots was also studied.

Nano LiFe2.5-xVxO4 and LiFe2.5-1.667xVxO4 systems were prepared by a sol–gel procedure at low temperatures. The influence of vacancies and vanadium doping on the structure parameters; lattice parameter, cation distribution, crystallite size, dislocation density, intrinsic distances, and bond angles between different cations and anions was fully studied by x-ray diffraction analysis applying Rietveld method. The nano nature and the particles morphology of the formed samples were examined by the transmission electron microscope. The change and the splitting, upon doping, of vibration bands obtained by Fourier-transform infrared spectroscopy were discussed. Magnetic measurements manifested that all samples exhibited a superparamagnetic behavior with a single domain characteristic. The change of saturation magnetization (Ms) and remnant magnetization (Mr) was correlated with the change in the crystallite size, and the cation distribution of different ions between different sites. The high concentrations of vacancies presented due to doping with vanadium ions is enhancing the electrochemical charge–storage properties of the samples making them a good potential electrode for Li-ion batteries.

Objective: The objective of the study was to compare maintenance versus single course of intravesical Bacillus Calmette–Guerin (BCG) in the management of high-risk nonmuscle invasive bladder cancer (NMIBC) regarding recurrence, progression, survival, and complications. Patients and Methods: After transurethral resection of bladder tumor (TURBT), Group I patients (33) received weekly doses of 90 mg of live attenuated Pasteur strain of BCG. The course was started 14 days after the second TURBT for 6 consecutive weeks. In Group II: 35 patients, the induction schedule was followed by 3 weekly instillations at months 3, 6, and 12 as a maintenance course. Recurrence, progression rates, survival, and toxicity were assessed in both the groups. Results: Patients with induction therapy alone had significantly higher recurrence rate than those received maintenance therapy (55.6% vs. 19.2%, P = 0.01). The 5-year recurrence-free survival rate was 41% and 78% in both the groups, respectively. There was no significant difference regarding the progression rate for both the groups. The mean 5-year progression-free time was comparable between the two groups. The 5-year progression-free survival was 69.8% for patients who underwent induction therapy alone compared to 70.7% for maintenance therapy. Overall local adverse events were significantly higher in patients who underwent maintenance treatment protocol. Statistical Analysis Used: SPSS package version 20 and Kaplan–Meier curves were used to evaluate the survival rate. Conclusions: Maintenance doses of BCG significantly decrease and delay the recurrence of high-risk NMIBC. However, there is no significant favor as regards tumor progression. Maintenance doses of BCG are significantly associated with a higher incidence of local adverse effects than induction doses alone.

Perovskite solar cell (CH3NH3PbI3) films were prepared with spin coating technique using different molarity concentrations of CH3NH3I and PbI2 in dimethyl sulfoxide (DMSO) solution as a solvent. Another set of films was formed with the same molarity concentrations, but chlorobenzene (CB) was dropped on the film surface as an anti-solvent at the last step of the spin coating. The phases formed, lattice parameters, crystallite size, and dislocation density were determined by applying Rietveld method for analyzing X-ray diffraction patterns measured for the samples. Field Emission Scanning Electron Microscope revealed that the number of pinholes were affected by the molarity concentrations of CH3NH3I and CB. The effects of molarity concentrations of the perovskite precursors solution, and using the anti-solvent on the transmission, reflection and absorption spectra and the direct optical band gaps were studied in detail. The dielectric constant, dissipation factor, and the optical conductivity of the films prepared with CB were observed to be higher than the corresponding films prepared without CB. The influence of molarity concentrations of MAPbI3 and the presence of CB on the photoluminescence (PL) peaks positions and their intensities was explored using PL technique with the laser source 532 nm.

Indium doped GaFeO3 (Ga1-xInxFeO3, 0 ≤ x ≤ 0.25) samples were synthesized by the ceramic’s procedure. The correlation between lattice parameter, different ions occupancies between different sites and the octahedral and tetrahedral distortion of indium doped GaFeO3 were studied in detail. Zero field cooled (ZFC) and field cooled (FC) magnetization measurements revealed that all samples exhibited a ferrimagnetic to paramagnetic phase transition below room temperature. Applying the law of approach to saturation, the 10% indium doped GaFeO3 sample revealed the highest saturation magnetization than the other samples. The dielectric constant (ε,), dielectric loss (tanδ), ac-conductivity, complex impedance parts and the hopping probability of electrons variation with temperature and frequency were studied in detail at different values of indium doping in GaFeO3 sample. The influence of doping on the activation energy of the conduction process was also investigated. Impedance Nyquist plot was used to differentiate between the grain and grain boundary contribution in indium doped GaFeO3 samples.