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(1 − x)ZnMn2O4/xNiFe2O4 (x = 0, 0.05, 0.1, 0.15, 0.2) nanocomposite samples were prepared employing co-precipitation procedure. Phase analysis of the measured x-ray diffraction patterns manifested the formation nanocomposites of two phases ZnMn2O4 (ZMO) and NiFe2O4 (NFO), and the phase percentage of each was determined applying Rietveld method. Analysis established the exchange of cations Zn, Mn, Ni, and Fe among the (ZMO) and (NFO) phases. Also, the influence of alloying parameter (x) on the cell parameters of (ZMO) and (NFO), crystallite size, and different IR vibrational bands was studied. For the prepared (1 − x)ZMO/xNFO nanocomposite samples, the influence of NFO amount of the absorbance, extinction coefficient, refractive index, optical bandgap, and other optical parameters were examined over different wavelength ranges using UV diffused absorption technique. The nonlinear optical behavior of the nanocomposite samples was increased as the percentage of NFO increases. The variations in the photoluminescence intensity and different emitted colors for the prepared nanocomposite samples were explored in detail.

Iron or chromium doped nano ZnMn2O4 samples (ZnMn2−xFexO4 or ZnMn2−xCrxO4, x = 0, 0.1, 0.15, 0.2) were prepared by the sol-gel procedure. Rietveld method analysis applied for Synchrotron x-ray diffraction data revealed single phase ZnMn2O4 (ZMO) tetragonal phase for the samples. The variation in the lattice parameters and crystallite size of different samples upon doping are discussed. X-ray photo-electron spectroscopic (XPS) technique was used to verify the incorporation of doped elements in ZMO matrix and to determine the cation oxidation states. All samples absorb light in wavelengths longer than 500 nm, demonstrating that they can efficiently absorb light in the visible range. Fe or Cr modified the light absorbance characteristics of ZMO sample. The sensitivity of ZMO sample to the daylight was increased as it doped with either Fe or Cr. The optical band gap energy, the photoluminescence intensity and the emitted colors from ZMO sample were affected by the kind of dopant element and the doped concentration. The behavior of extinction coefficient, dielectric constant (real and imaginary) and the optical conductivity of all samples were also explored. Fe or Cr doped samples exhibited a paramagnetic behavior. The small dielectric value and the relative small bandgap nominated the doped materials to be used in optoelectronic applications.

Nano ZnMn2−xCrxO4 samples (x = 0, 0.05, 0.15, 0.2) were synthesized by the sol–gel procedure. The synchrotron X-ray diffraction technique was used to investigate the developed phases, cation distributions of different ions between different sites, lattice parameters, and crystallite size upon increasing the amount of Cr doping in nano ZnMn2O4. X-ray photoelectron spectroscopy (XPS) was utilized to explore the cation oxidation state and the elemental composition of the samples. The valence state of the incorporated chromium is determined to be Cr3+ only. The effect of Cr doping, frequency, and temperature on the dielectric constant, dielectric loss, ac conductivity, complex impedance, and modulus was studied in detail. At a low temperature range, the samples exhibited a semiconductor feature, while at a higher temperature range, the samples revealed metallic behavior. Also, the conduction-type mechanism for each doped sample was determined. The activation energy was affected by the amount of Cr doping. A sample with 15% Cr doping has the highest conductivity among the other samples. Also, the effect of doping and temperature on the Nyquist diagram was examined.

Nano CuCo2-xMxO4 (x = 0, 0.1, 0.2, M = Cr or Fe) samples were synthesized by hydrothermal method. Synchrotron x-ray diffraction data obtained for the samples were subjected to phase analysis and manifested a single-phase cubic spinel structure for Cr-doped samples, while for Fe-doped samples two phases were identified. Cation distribution and cell parameter (a) were obtained from Rietveld X-ray diffraction analysis. FTIR analysis affirmed the formation of the cubic spinel and the cation distribution obtained. The nano nature of the samples and the particle morphology were examined by high-resolution transmission electron microscope (HRTEM) with selected area electron diffraction (SAED). UV-diffuse reflectance revealed that all samples have two optical energy gaps. For all Fe doped samples, the optical band gaps decreased, while for Cr-content x = 0.1 the bandgaps increased then reduced for x = 0.2. Doped samples exhibited a blue or red shift depending on the kind and amount of the dopant ions. The PL intensity and the emitted colors depended on the kind and amount of the dopant ions. Magnetic measurements disclosed the paramagnetic nature of CuCo2O4, while a weak ferromagnetic is revealed for CuCo2-xCrxO4 and a ferromagnetic nature for CuCo2-xFexO4. Lowering the bandgap upon doping could make better mobility of lattice oxygen and enhancing the catalyst reducibility. Thus, the Cr and Fe-doped samples are expected to have better catalytic activity than the pristine one.

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.

Novel nano quaternary metals solid solutions from MgFe2O4 and ZnMn2O4 were synthesized using a sol-gel procedure. The development of a solid solution and the formed phase were examined by phase analysis utilizing the X'Pert High Score Plus program and Fourier transform infrared (FTIR) spectroscopy technique. Rietveld analysis of X-ray diffraction data (XRD), scanning electron microscope (SEM/EDS) and transmission electron microscope (TEM) were applied to determine the lattice parameters, crystallite size, different cations distribution and elemental analysis of the formed solid solutions. The measured dielectric properties of obtained solid solutions are found to be affected by the composition ratio (x). The solid solution (1-x)ZnMn2O4/(x)MgFe2O4 samples exhibited a ferroelectric–paraelectric transition at ferroelectric Curie temperature (Tc). The different hopping mechanisms in the different samples were also examined. The electrochemical performance was tested and influence of composition ratio (x) on the cathodic and anodic potential was investigated. The specific capacitance (Cs) value of electrodes depended on the composition ratio (x) beside the type of cations forming oxides. The (0.9)MgFe2O4/(0.1)ZnMn2O4 sample showed the best performance as a supercapacitor material. The outstanding electrochemical property of the (0.9)MgFe2O4/(0.1)ZnMn2O4 electrode was further confirmed by EIS inspection. The super stability of MgFe2O4/ZnMn2O4 solid solution could be attributed to the activation of the solid solution materials during the CV cycling and the synergistic effects.

Non-stoichiometric cadmium sulfide, CdS0.9, nanomaterials doped with Mn, Co, Cu, and Zn (CdS0.9M0.1, M = Mn, Co, Cu, Zn) were prepared using a thermolysis procedure. X-ray diffraction analysis revealed that all doped samples have the same CdS structure (hexagonal and cubic) except the Co-doped sample, where some slight cobalt oxides were detected. The influence of different transition metals doping on the structural parameters of the phases developed has been examined by performing Rietveld analysis, also the residing of doped metals at the possible crystallographic sites and the possibility to oxygen ion diffusion into the matrix were also studied. Images from high-resolution transmission electron microscope confirmed the quantum dots nature of the formed samples. The optical bandgap could be tailored and photoluminescence properties of the samples were affected by the different types of doped metals. The doped samples emitted violet, blue, and green colors depending on the type of doped metals. DFT calculation was performed to discuss the possibility of the presence of oxygen ions in doped non-stoichiometric CdS samples. DFT calculations demonstrated that the Cu-doped non-stoichiometric CdS sample has the highest photoconductivity in the infrared range. The modified properties of CdS0.9M0.1 nanomaterials by changing the doped metals make them good candidates for photocatalytic activity and optoelectronics applications.

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.

Undoped and 10% Mg or Cu-doped ZnS quantum dots (Zn0.9Mg0.1S and Zn0.9Cu0.1S) were prepared by a simple chemical method at low temperature (300 °C). The effect of doping on structural characteristics was investigated using Rietveld profile method and the high-resolution transmission electron microscope techniques. Differential scanning calorimetry (DSC) scans were recorded in the temperature range 23–600 °C with different heating rates (5 to 30 °C/min). The model-free isoconversional method was applied to explore the effect of doping on the reaction and the growth mechanism of nano-ZnS. Diffuse UV reflectance revealed an increase of the optical energy gap upon doping with Mg, while it decreased as ZnS was doped with Cu. The change in energy gap upon doping was explained using density function theory calculation. The photoluminescence (PL) spectra revealed violet, blue, green colors depended on the composition and excitation wavelength used in the study. The intensity of PL has been increased for doped samples compared with pristine ZnS. Tuning the energy gap of ZnS through doping enable applications for light-harvesting and photocatalytic degradation in the visible region.

Characterization of thermoluminescence (TL) properties of lithium borate glass samples doped with different concentrations of dysprosium (Dy) was carried out. Samples were prepared using a melting method at 1100°C and irradiated with β-particles. The glass samples doped with 0.1% Dy displayed the best TL dosimetric properties compared with other compositions. Deconvoluted analyses of the glow curves displayed five overlapping TL glow peaks located between 392.0 and 510.3 K. A good linear TL dose-response for β-particles was obtained in the dose range 66.6 mGy to 33.3 Gy. The minimum detectible dose was evaluated to be 205.4 μGy and samples revealed thermal fading in 312 h to 29% of their original value.

Nanocomposites (1−x)MnS‒xZnS (x = 0, 0.25, 0.5, 0.75, 1) heterostructures were synthesized by a simple chemical procedure at low temperature (300 °C). The influence of the alloying ratio (x) on the phases developed was investigated utilizing the Rietveld X-ray diffraction (XRD) analysis and Fourier transform infrared (FTIR). Zinc sulfide crystallized in one phase having zincblende structure, while manganese sulfide was formed in three phases having cubic and hexagonal structures. The determined crystallite size for ZnS was in the range 3–4 nm, resembling quantum dots, while for the cubic MnS phase the size was bigger in the range 15–20 nm, and it is much bigger for MnS hexagonal phase, about 76 nm. A High-resolution transmission electron microscope (HRTEM) images confirmed the big difference in particle sizes of MnS and ZnS. The UV diffused reflectance was obviously affected by the ratio of MnS to ZnS in the matrix; the intermediate composites (0.25, 0.5, and 0.75) had bandgap energy less than those of pure MnS and ZnS. The refractive index value was influenced by the degree of crystallinity and density of the samples. Photoluminescence (PL) analysis revealed high dependence on the sample composition with ZnS and the intermediate composites samples had broader spectra compared to the MnS sample; the intermediate samples were blue shifted. Also, PL intensities of intermediate nanocomposites were less than those of MnS and ZnS samples.

Nanocomposites of polyaniline loaded with different weight-fractions of double-wall carbon nanotubes were fabricated by in situ polymerizations of the polyaniline in the presence of double-wall carbon nanotubes. The composition of the nanocomposites is examined by X-ray diffraction and scanning electron microscopy techniques. The functionality of the synthesized composites was studied by electrical conductivity and fluorescence analyses. The dc conductivity of polyaniline was increased by introducing 2.5 wt% of DWCNTs into polyaniline matrix. The fluorescence emission from the double-wall carbon nanotubes/polyaniline showed a broad emission range in the visible region between 350 and 560 nm with appreciable enhancement in the intensity at 434 nm.

Undoped and doped with nano-ZnO (Zn0.9X0.1O, X = Co, Cu and Mn) blended polymers (70% polyvinyl alcohol/30% polyvinyl pyrrolidone) were formed using solid-state reaction and casting methods. X-ray diffraction measurements were used to examine the incorporation of the nanofiller into the polymer matrix. Rietveld analysis showed an average crystallite size of 20 nm for ZnO with a little change upon doping Co, Cu, or Mn. The variations in the absorbance, extinction coefficient, refractive index, direct optical band gap energy, the single-oscillator energy, the oscillator strength and static refractive index of the blend with the nanofiller were studied in detail. The optical bandgap of the pristine blend, 4.97 eV, was reduced upon doping reaching a minimum of 4.82 eV for pure ZnO. The obtained values of electric characteristics and nonlinear optical properties are affected by the kind of dopant and the value of wavelength used. The reduction obtained in the optical band gap can nominate the doped blended polymers to be used as an absorbing layer in a solar cell to improve the efficiency of photovoltaic devices. Also, the enhancement of the nonlinear parameters nominates them to be applied in different nonlinear optical and photonic applications. The emitted fluorescence spectra depended on the excitation wavelength and the kind of dopants.

Nano Zn0.75Cd0.25S and Zn0.65Cd0.25M0.1S (M = Co, Fe, Mn, V) doped 70%PVA/30%PVP polymer blends were formed. The synchrotron x-ray diffraction was employed to investigate the nature of the nanofiller. Rietveld analysis of x-ray diffraction data revealed a single ZnS phase for the nanofillers and confirmed the inclusion of the M-metal into the ZnS lattice. SEM images of PVA/PVP doped blends revealed uniform film morphology and nanofiller distribution. The highest transmittance (90%) was observed in the undoped blend at the visible region, and it decreased as the PVA/PVP doped with the nanofiller reached its minimum value (15%) as the blend doped with Zn0.75Cd0.25S (ZCS). The refractive index value of blended polymer changed in the order 0.750.25ZCS > ZCS/Co > ZCS/Mn > ZCS/V > ZCS/Fe > undoped blended polymer at 600 nm. The highest dielectric values were observed in PVA/PVP blend doped with ZSC/Mn or ZSC/Co. The nonlinear optical parameters reached their highest value in UV and visible regions as the blended polymer doped with ZSC/Mn and ZCS, respectively. The emitted colors of different blended polymers and their intensities were depended on the kind of nanofillers and the excitation wavelengths.

(1−x) CuCo2O4-xCuS (x = 0, 0.1, 0.25, 0.5) nanocomposite samples were prepared using hydrothermal and thermolysis procedures. The crystal structure and the percentages of phases formed in the nanocomposite samples were studied employing Fullprof software. X-ray photoelectron spectroscopy (XPS) was carried out to identify the different ions present in samples and their oxidation states. The specific capacitance is remarkably enhanced after adding CuS emphasizing the synergistic effect between CuCo2O4 and CuS. The optimum performance of 735 Fg−1 was achieved for 25% CuS. At a higher amount of CuS, the electrochemical activities become less compared with a low CuS amount. The supercapacitor electrode of 0.75CuCo2O4/0.25CuS exhibited high stability with a longer discharging time compared with pristine CuCo2O4 and CuS. Also, it maintained 88.9% of its initial Cs and consequently, this material can work as an excellent supercapacitor electrode. Electrochemical impedance spectroscopy (EIS) analysis was also performed.

Background Breast cancer is the most common non-skin cancer and the second leading cause of cancer related death in women. Breast cancer strikes women of all ages, races, ethnicities, socioeconomic strata, and geographic locales. Once breast cancer is diagnosed, the tumor stage has to be accurately determined before therapy chosen and the prognosis known. Aim of the Work to highlight the role of PET-CT imaging in staging of patients with breast cancer. Patients and Methods This study was carried out on a total of 51 female patients biopsy-proved to have cancer breast coming to perform PET/CT scans for staging, pre-operative or pre-therapeutic assessment with ages ranging from 27 to 78 years, in specialized private center in Cairo using combined PET-CT machine (Phillips Ingenuity TF PET/CT 128 Slice) from October 2017 to June 2019. Results Combined PET/CT staged 3 patients as stage IA, 10 patients as stage IIA, 6 patients as stage IIB, 2 patients as stage IIIA, 3 patients as stage IIIB, 2 patients as stage IIIC and 25 patients as stage IV. Out of 51 patients, combined PET/CT upgraded the staging of 13 patients compared to initial CT staging. Conclusion PET/CT is the technique of choice and indispensable tool for evaluation of the patients with breast cancer.

Blended polymers, polyvinyl alcohol (PVA)/polyvinyl pyrrolidone (PVP), embedded with nano Sn0.75M0.25S2, (M = Y, Fe, Cr, V) were prepared using thermolysis and casting procedures. Rietveld refinement was used to investigate the structure and microstructure of the powder nano-filler Sn0.75M0.25S2, (M = Y, Fe, Cr, V). SEM images of 50%PVA/50%PVP doped with the powder samples revealed a homogeneous distribution of the nano-filler over the polymer blend. X-ray diffraction patterns exhibited small degree of crystallinity coupled with a diffuse scattering referring to an amorphous phase. Transmission FTIR spectra confirmed the incorporation of nano-filler into the blend matrix. The effect of nano-filler on the transmittance, optical absorption coefficient, extinction coefficient, refractive index, the optical bandgap, Urbach energy, steepness parameter, optical conductivity, the real and imaginary parts of the dielectric constant of the 50%PVA/50%PVP blend was studied using UV–vis spectrophotometry technique. Fluorescence (FL) spectra analysis revealed that the emitted color and Fl intensity depended on the kind of nano-filler and excitation wavelength.

(1-x)ZnMn2O4/xNiFe2O4 (x = 0, 0.05, 0.1, 0.15, 0.2) nanocomposite system was prepared using the sol–gel technique. Rietveld analysis revealed the presence of two phases ZnMn2O4 and NiFe2O4 for all composites, but with phase percentages different from nominated values of (x). The effect of alloying parameter (x) on the lattice parameters and crystallite size of the obtained phases was also examined. The oxidation states of different ions were determined using X-ray photoelectron spectroscopy (XPS) technique. For the prepared nanocomposite samples, the dependence of dielectric constant, impedance and electric modulus on the frequency and temperature was performed using complex impedance technique. It was found that the obtained samples have ferroelectric characteristics. The degree of correlation for the different nanocomposite samples was explored using ac conductivity.

An opportunity to operate by laser-induced nonlinear optical efficiencies of Ga2S3–La2S3 glasses doped with Er3+ and La3+ ions in the visible and near-infrared spectral ranges was explored. The laser-stimulated nonlinear optical properties were studied. The observed laser power and temperature dependences of the laser-stimulated second-harmonic generation and third-harmonic generation confirm the huge role of anharmonic phonon subsystems. Due to an occurrence of local structural distortions, the efficiency of laser nonlinear optical generation has been enhanced. Simultaneous occurrence of the second and third-order nonlinear optical response may indicate on the possibility of multifunctional applications of the investigated glasses in different electronic devices.

Cd1−xMnxFe2O4/PMMA nanocomposites are prepared using hydrothermal and casting procedures. Rietveld analysis is performed for Cd1−xMnxFe2O4 (x = 0, 0.3, 0.5, 0.7) nano ferrite. X-ray diffraction and Fourier transform infrared are used to examine the homogenous distribution of Cd1−xMnxFe2O4 throughout PMMA matrix. The influence of nano ferrite on the absorbance, transmittance and refractive index for all samples are examined utilizing UV–Vis spectrophotometer technique. The direct energy gap and other optical parameters of nanocomposite samples are changed depending on the amount of manganese doped Cd-ferrite. All nanocomposite samples display four sub-emissions in UV and visible regions.

We demonstrated experimentally an opportunity to form space grating patterns in Ag3AsS3 semiconductor crystals under an influence of coherent femtosecond (195 fs) laser beams. The observation of the laser stimulated gratings has been performed using a cw He–Ne laser with power about 15 mW at 1150 nm wavelength. The photoinducing femtosecond laser with pulse duration about 190 fs and frequency 65 MHz bandpass has been used in the two-beam coherent regime at wavelength 1045 nm. The set of dichroic mirrors, polarizers, and lenses have been applied to form two space-separated beams, which interact with the studied Ag3AsS3 trigonal single crystals. The treatment has been performed during additionally applied dc-electrical strength equal to about 8 kV/cm with a frequency about 20 kHz directed perpendicularly to the optical axis. The monitoring of the photo-thermal effects and photo-destruction have been done using the optical fiber spectrometer Ocean Optics with spectral resolution 1 nm.

We demonstrated a way to achieve tunable fluorescence from reduced graphene oxide (rGO) by selecting appropriate solvents. This work begins a new area of research that seeks to improve the fluorescence properties of rGO, offering novel strategies for realizing printed flexible opto-electronics with tunable device performance. We investigated the effect of solvents and report that solvents play a vital role in the optical properties of rGO. The dispersion of rGO was analyzed by UV–Visible spectroscopy, FTIR spectroscopy, and fluorescence spectroscopy, demonstrating that rGO dissolved in polar solvents exhibits enhanced fluorescence covering the entire visible range as opposed to non-polar solvents. The synthesis strategy may possibly facilitate the manipulation and processing of rGO toward vital printed flexible optoelectronics applications, which could be tuned by selecting a suitable solvent.

Rapid synthesis of cesium-doped hydroxyapatite (Ca10(PO4)6(OH)2, (HAp)) by rapid microwave synthesis technique is reported. The crystal, chemical, and dielectric properties, along with the phase co...

A new type of elastooptic materials based on PbO–Bi2O3–Ga2O3–BaO glasses have been fabricated. The studies of piezooptical effect at 1150 nm He-Ne laser wavelength have shown that the elastoopticity is crucially dependent on the nanoparticle (NP) sizes. The optimal effect exists at NP concentration equal to about 25%. The principal role of the interfaces between the glass nanoparticles and photopolymer PVA matrices is found. The piezooptic effect has shown sensitivity to the temperature also. The obtained values of piezooptical coefficients are compared with other glasses.

We demonstrate a possibility to vary structural, morphological and optoelectronics parameters for kesterite Cu2ZnSnS4 nanocrystalline films using external laser beams at 1540 nm, and 770 nm or 1064 nm, and 532 nm. The illumination is performed both by single mode laser beams as well as by bicolor coherent treatment. The principal changes were observed for the density of electronic states in the valence band, third-order nonlinear optics, surface states. The energy density of the fundamental laser beams was continuously varied up to 250 J/m2. The role of photo-thermal and phonon anharmonic contributions play here crucial role. The maximal changes of the electronic density of states and effective masses were achieved during simultaneous illumination by 1540 nm/770 nm Er: glass laser coherent bicolor laser beams. This result correlates well with the occurrence of the optical interference gratings, the formation of the nanocrystallites and surface morphology.