This contribution reports on the characterization of laser-induced plasma generated from the surf... more This contribution reports on the characterization of laser-induced plasma generated from the surface of magnesium oxide dispersed in Poly (vinyl alcohol) (MgO/PVA) pellet using laser induced breakdown spectroscopy. For this purpose, Nd:YAG Q-switched pulsed laser with energy ranging from 50 to 250 mJ, operating at both fundamental (1064 nm) and second harmonic (532 nm) was focused on the sample to generate plasma. Based on experimental results, emission lines of magnesium have been used to calculate the plasma parameters. The plasma electron temperature as a function of laser energy ranged from (8596–8900) K and (8000-8700) K, and the electron density from (1.12–1.8) × 10^16 cm^–3, (2.9–4.5) × 10^16 cm^–3 measured at 1064 nm and 532 nm, respectively. Although these values increased with the increase in laser irradiance, they showed different rates of increase with different wavelength dependency.
This study aims to prepare transparent defective p-type TiO 2 films using defects chemistry via t... more This study aims to prepare transparent defective p-type TiO 2 films using defects chemistry via the hydrothermal method, showing that the metal vacancies (V Ti) may be easily presented into undoped oxide, then constructing a p-n homojunction diode. The defective TiO 2 depicts the p-type conductivity with a high charge mobility which was verified via the Hall Effect measurement. The influence of growth time upon the TiO 2 nanorods' morphological, structural, and optical properties was investigated and analyzed using Field Emission Scanning Electron Microscopy (FESEM), X-ray Diffraction (XRD), X-Ray Photoelectron Spectroscopy (XPS), and ultraviolet-visible spectroscopy methods (UV-VIS). The measurements of XPS were utilized for investigating the chemical conditions of the constituent elements and the XRD analysis of deposited films for (24 h) at (180 °C) have confirmed the formation of the polycrystalline-tetragonal phase anatase as a major phase with a minor rutile phase. The FESEM measurements of TiO 2 films evinced the grass shape nanostructure with a diameter range (of 26-76) nm for the prepared films with different growth times. The stoichiometry ratio of (Ti) and (O) in TiO 2 films was confirmed by (EDX) analysis to be 2:1. Optical properties have been investigated, the transmittance, absorbance, and energy gap at various growth times were measured and computed, and the results manifested that the rod length reduced the transmittance, while it augmented the absorbance with slight change in the energy gap, the PL intensity of defective p-type TiO 2 smaller than of n-type. The p-n homo-junction demonstrated the distinct diode-like behavior with ideality factor n = 32.069. These findings could have far-reaching consequences for the development of nanostructured metal-oxide solar cells, photo-catalysts, LEDs, photodiodes, and photo-electrochemical devices.
Indian Journal of Public Health Research and Development, 2018
Concentrations of Cr, Pb, Cu, Zn, Cd and Ni in soil samples gathered from different cities in Ira... more Concentrations of Cr, Pb, Cu, Zn, Cd and Ni in soil samples gathered from different cities in Iraqi were estimated via laser induced breakdown spectroscopy (LIBS). A total of 14 composite soil samples were collected at depths 0–10 cm, including green areas, urban parks and industrial residential districts. Qualitative and quantitative analysis of the samples were achieved by using the locally developed LIBS set up equipped with Q-switched Nd: YAG laser and optical spectrum analyzer. To validate the analysis results, Atomic absorption spectrometry (AAS) was used to analyses the samples as well. PCA was utilized to identify possible sources of detected metals. Concentrations of heavy metals (HMs) in samples were found to decrease with increasing of the distance of the communities from the pollution sources. The results of the multivariate analysis showed Cr, Cu, and Ni concentrations is controlled by gas stations, while Pb, Zn, Cd, and Mn in examined soil are mainly affected by deposi...
In this study, gold nanoparticles dispersed in poly(methyl methacrylate) were prepared by ablatio... more In this study, gold nanoparticles dispersed in poly(methyl methacrylate) were prepared by ablation with a 532 nm laser at different ablation times of 10, 20, and 30 min. The formation of gold nanoparticles in poly(methyl methacrylate) solution was confirmed using ultraviolet-visible spectroscopy, and their size and concentration were estimated using a dynamic light scattering method and atomic absorption spectroscopy, respectively. Linear optical studies indicated a slight blue shift in the surface resonance plasmon of the absorption wavelength with the increase of ablation time. The nonlinear optical properties of the nanocolloids were investigated by using a continuous wave of the 532 nm diode laser with a beam power of 40 mW in the Z-scan technique. All investigated samples showed negative and large thermally induced nonlinear refractive indices. The results confirm that the nonlinear refractive index increases with the increase in ablation time.
This contribution reports on the characterization of laser-induced plasma generated from the surf... more This contribution reports on the characterization of laser-induced plasma generated from the surface of magnesium oxide dispersed in Poly (vinyl alcohol) (MgO/PVA) pellet using laser induced breakdown spectroscopy. For this purpose, Nd:YAG Q-switched pulsed laser with energy ranging from 50 to 250 mJ, operating at both fundamental (1064 nm) and second harmonic (532 nm) was focused on the sample to generate plasma. Based on experimental results, emission lines of magnesium have been used to calculate the plasma parameters. The plasma electron temperature as a function of laser energy ranged from (8596-8900) K and (8000-8700) K, and the electron density from (1.12-1.8) × 10 16 cm-3 , (2.9-4.5) × 10 16 cm-3 measured at 1064 nm and 532 nm, respectively. Although these values increased with the increase in laser irradiance, they showed different rates of increase with different wavelength dependency.
In this study the boards were fabricated from unsaturated polyester resin reinforced by rice husk... more In this study the boards were fabricated from unsaturated polyester resin reinforced by rice husk and date palm fibers, with the total volume fraction of reinforcement materials was(30%) using different value of filler loading including the ratios (0/30, 5/25, 10/20 15/15, 20/10, 25/5 and 30/0) for volume fraction of date palm fibers/ rice husk, two groups of the hybrid composite were prepared depending on the length of palm fibers, the first group have palm fibers its length 2-3 mm and second group have short fibers its length less than 1mm. The fabricated boards were evaluated for the mechanical properties (tension, compression, flexural, and impact tests) for all the prepared samples were studied. The results from this work show that all of these properties increase with increased the volume fraction of palm fiber at the expense of the proportion of rice husks in hybrid composite. Decreasing the length of fibers from (2-3mm) to micro-sized length (less than 1mm) increased the mechanical properties of flexural strength, maximum shear stress, flexural modulus, and fracture toughness of the prepare composites. Moreover the mechanical properties of the polyester composite reinforced with date palm fibers gave better mechanical properties than the polyester composite reinforced with rice husk.
In this work, we reported a study on the hydrothermal process used to create TiO2 NRs films on FT... more In this work, we reported a study on the hydrothermal process used to create TiO2 NRs films on FTO substrate utilizing two various solutions, the first one is composed of (ethanol, and titanium butoxide) while the second is composed of (HCl, DIW, and titanium butoxide). The study on the structural, morphological, optical, and electrical properties helped to identify the characteristics of the TiO2 film which were prepared by using different solvents, the first sample (TO1) presented anatase-phase crystal structure with (3.2 eV) energy gap while the second (TO2) presented a Rutile phase with (3 eV) energy gap. The (nanorod) morphology was observed for the (TO2) sample while irregular grains were found for the (TO1) sample. Transmittance measurements have been used to investigate the optical properties, which revealed that both samples were transparent in the visible wavelength range, and absorption coefficients were higher for sample (TO2) with a rutile phase. The activation energy was (0.0226) eV and (0.0643) eV for both samples (TO1) and (TO2), respectively. The n-type conductivity was confirmed by Hall Effect measurement for both samples. The highest conductivity (300.655) (Ω-1 .cm-1) and carrier consternation (1.07355 ×10 17) (cm-3) were attained from sample (TO1).
This contribution reports on the characterization of laser-induced plasma generated from the surf... more This contribution reports on the characterization of laser-induced plasma generated from the surface of magnesium oxide dispersed in Poly (vinyl alcohol) (MgO/PVA) pellet using laser induced breakdown spectroscopy. For this purpose, Nd:YAG Q-switched pulsed laser with energy ranging from 50 to 250 mJ, operating at both fundamental (1064 nm) and second harmonic (532 nm) was focused on the sample to generate plasma. Based on experimental results, emission lines of magnesium have been used to calculate the plasma parameters. The plasma electron temperature as a function of laser energy ranged from (8596–8900) K and (8000-8700) K, and the electron density from (1.12–1.8) × 10^16 cm^–3, (2.9–4.5) × 10^16 cm^–3 measured at 1064 nm and 532 nm, respectively. Although these values increased with the increase in laser irradiance, they showed different rates of increase with different wavelength dependency.
This study aims to prepare transparent defective p-type TiO 2 films using defects chemistry via t... more This study aims to prepare transparent defective p-type TiO 2 films using defects chemistry via the hydrothermal method, showing that the metal vacancies (V Ti) may be easily presented into undoped oxide, then constructing a p-n homojunction diode. The defective TiO 2 depicts the p-type conductivity with a high charge mobility which was verified via the Hall Effect measurement. The influence of growth time upon the TiO 2 nanorods' morphological, structural, and optical properties was investigated and analyzed using Field Emission Scanning Electron Microscopy (FESEM), X-ray Diffraction (XRD), X-Ray Photoelectron Spectroscopy (XPS), and ultraviolet-visible spectroscopy methods (UV-VIS). The measurements of XPS were utilized for investigating the chemical conditions of the constituent elements and the XRD analysis of deposited films for (24 h) at (180 °C) have confirmed the formation of the polycrystalline-tetragonal phase anatase as a major phase with a minor rutile phase. The FESEM measurements of TiO 2 films evinced the grass shape nanostructure with a diameter range (of 26-76) nm for the prepared films with different growth times. The stoichiometry ratio of (Ti) and (O) in TiO 2 films was confirmed by (EDX) analysis to be 2:1. Optical properties have been investigated, the transmittance, absorbance, and energy gap at various growth times were measured and computed, and the results manifested that the rod length reduced the transmittance, while it augmented the absorbance with slight change in the energy gap, the PL intensity of defective p-type TiO 2 smaller than of n-type. The p-n homo-junction demonstrated the distinct diode-like behavior with ideality factor n = 32.069. These findings could have far-reaching consequences for the development of nanostructured metal-oxide solar cells, photo-catalysts, LEDs, photodiodes, and photo-electrochemical devices.
Indian Journal of Public Health Research and Development, 2018
Concentrations of Cr, Pb, Cu, Zn, Cd and Ni in soil samples gathered from different cities in Ira... more Concentrations of Cr, Pb, Cu, Zn, Cd and Ni in soil samples gathered from different cities in Iraqi were estimated via laser induced breakdown spectroscopy (LIBS). A total of 14 composite soil samples were collected at depths 0–10 cm, including green areas, urban parks and industrial residential districts. Qualitative and quantitative analysis of the samples were achieved by using the locally developed LIBS set up equipped with Q-switched Nd: YAG laser and optical spectrum analyzer. To validate the analysis results, Atomic absorption spectrometry (AAS) was used to analyses the samples as well. PCA was utilized to identify possible sources of detected metals. Concentrations of heavy metals (HMs) in samples were found to decrease with increasing of the distance of the communities from the pollution sources. The results of the multivariate analysis showed Cr, Cu, and Ni concentrations is controlled by gas stations, while Pb, Zn, Cd, and Mn in examined soil are mainly affected by deposi...
In this study, gold nanoparticles dispersed in poly(methyl methacrylate) were prepared by ablatio... more In this study, gold nanoparticles dispersed in poly(methyl methacrylate) were prepared by ablation with a 532 nm laser at different ablation times of 10, 20, and 30 min. The formation of gold nanoparticles in poly(methyl methacrylate) solution was confirmed using ultraviolet-visible spectroscopy, and their size and concentration were estimated using a dynamic light scattering method and atomic absorption spectroscopy, respectively. Linear optical studies indicated a slight blue shift in the surface resonance plasmon of the absorption wavelength with the increase of ablation time. The nonlinear optical properties of the nanocolloids were investigated by using a continuous wave of the 532 nm diode laser with a beam power of 40 mW in the Z-scan technique. All investigated samples showed negative and large thermally induced nonlinear refractive indices. The results confirm that the nonlinear refractive index increases with the increase in ablation time.
This contribution reports on the characterization of laser-induced plasma generated from the surf... more This contribution reports on the characterization of laser-induced plasma generated from the surface of magnesium oxide dispersed in Poly (vinyl alcohol) (MgO/PVA) pellet using laser induced breakdown spectroscopy. For this purpose, Nd:YAG Q-switched pulsed laser with energy ranging from 50 to 250 mJ, operating at both fundamental (1064 nm) and second harmonic (532 nm) was focused on the sample to generate plasma. Based on experimental results, emission lines of magnesium have been used to calculate the plasma parameters. The plasma electron temperature as a function of laser energy ranged from (8596-8900) K and (8000-8700) K, and the electron density from (1.12-1.8) × 10 16 cm-3 , (2.9-4.5) × 10 16 cm-3 measured at 1064 nm and 532 nm, respectively. Although these values increased with the increase in laser irradiance, they showed different rates of increase with different wavelength dependency.
In this study the boards were fabricated from unsaturated polyester resin reinforced by rice husk... more In this study the boards were fabricated from unsaturated polyester resin reinforced by rice husk and date palm fibers, with the total volume fraction of reinforcement materials was(30%) using different value of filler loading including the ratios (0/30, 5/25, 10/20 15/15, 20/10, 25/5 and 30/0) for volume fraction of date palm fibers/ rice husk, two groups of the hybrid composite were prepared depending on the length of palm fibers, the first group have palm fibers its length 2-3 mm and second group have short fibers its length less than 1mm. The fabricated boards were evaluated for the mechanical properties (tension, compression, flexural, and impact tests) for all the prepared samples were studied. The results from this work show that all of these properties increase with increased the volume fraction of palm fiber at the expense of the proportion of rice husks in hybrid composite. Decreasing the length of fibers from (2-3mm) to micro-sized length (less than 1mm) increased the mechanical properties of flexural strength, maximum shear stress, flexural modulus, and fracture toughness of the prepare composites. Moreover the mechanical properties of the polyester composite reinforced with date palm fibers gave better mechanical properties than the polyester composite reinforced with rice husk.
In this work, we reported a study on the hydrothermal process used to create TiO2 NRs films on FT... more In this work, we reported a study on the hydrothermal process used to create TiO2 NRs films on FTO substrate utilizing two various solutions, the first one is composed of (ethanol, and titanium butoxide) while the second is composed of (HCl, DIW, and titanium butoxide). The study on the structural, morphological, optical, and electrical properties helped to identify the characteristics of the TiO2 film which were prepared by using different solvents, the first sample (TO1) presented anatase-phase crystal structure with (3.2 eV) energy gap while the second (TO2) presented a Rutile phase with (3 eV) energy gap. The (nanorod) morphology was observed for the (TO2) sample while irregular grains were found for the (TO1) sample. Transmittance measurements have been used to investigate the optical properties, which revealed that both samples were transparent in the visible wavelength range, and absorption coefficients were higher for sample (TO2) with a rutile phase. The activation energy was (0.0226) eV and (0.0643) eV for both samples (TO1) and (TO2), respectively. The n-type conductivity was confirmed by Hall Effect measurement for both samples. The highest conductivity (300.655) (Ω-1 .cm-1) and carrier consternation (1.07355 ×10 17) (cm-3) were attained from sample (TO1).
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Papers by Aseel S . Jasim