In this research the electrical conductivity and optical measurements were made on the Iron Oxide (Fe2O3) films prepared by chemical spray pyrolysis method as a function of thickness (250, 350, 450, and 550)  20 nm.    The measurements of electrical conductivity (σ), activation energies (Ea1, Ea2),and optical constant such as absorption coefficient, refractive index, extinction coefficient and the dielectric constants for the wavelengths in the range (300-900) nm have been investigated on (Fe2O3) thin films as a function of thickness. All films contain two types of transport mechanisms, and the electrical conductivity (σ) increases whereas the activation energy (Ea) would decrease as the films thi

      In this work, the performance of single-mode optical fibers (SMFs) for ultraviolet (UV) radiation monitoring and dosimetry applications is presented. In particular, this work will focus on the Radiation-Induced Absorption (RIA) phenomena in the Near-Infrared domain (NIR). Such phenomena play a very important role in the sensing mechanism for SMF. Single mode fibers with a diameter of 50 µm were used for this purpose. These fibers were dipped into germanium (Ge) solution with different concentrations (1, 3, and 5 wt%) to produce the sensing part of the sensor. For all optical fiber sensors under investigation, the results indicated the dependence of the RIA on the applied UV radiation energy. Also, a redshi

Evaluation of trace elements in Iraqi chewing gums are unavailable, particularly pollution of toxic elements, materials which change the values of PH in the Oral. Atomic Absorption Spectroscopy (AAS) were successfully employed to determine the concentration of 7 trace elements (essentially toxic and nonessential) and the PH, in thirteen different brands of chewing gum generally consumed in Iraq. Combined wet and dry digestion procedures were applied. Two types of heated graphite tubes were used, coated and uncoated tubes treated with tungsten solution. Result showed that Cu, Al and Zn were at very high levels in almost all brands whereas Mn was found to be high in brands A and O only.

The present work reports the performance of three types of polyethersulfone (PES) membrane in the removal of highly polluting and toxic lead Pb2+ and cadmium Cd2+ ions from a single salt. This study investigated the effect of operating variables, including pH, types of PES membrane, and feed concentration, on the separation process. The transport parameters and mass transfer coefficient (k) of the membranes were estimated using the combined film theory-solution-diffusion (CFSD), combined film theory-Spiegler-Kedem (CFSK), and combined film theory-finely-porous (CFFP) membrane transport models. Various parameters were used to estimate the enrichment factors, concentration polarization modulus, and Péclet number. The pH values signif

The optical modulator was designed by using iterated function

systems (IFSs) by IFS Construction Kit program. The modulator was inserted into the optical system using ZEMAX optical design program. In this program, it is assumed that the modulator is made from one of Ø¢ the infrared transmitting materials. Eight materials at room temperature were used in this study; these are IRTRAN materials, Si, and Ge for the range of 3-9 l-lm.

Systems were evaluated and analyzed by using different criteria,

including spot diagram, modulation transfer function, and point spread function. The effect of optical modulator change with the chang of Ø¢ its material results in focusing of functions and frequencies as requ

In this work, As60Cu40-xSex thin films were synthesized, and the pulsed laser deposition method was used to study the effected partial replacement of copper with selenium. The electrical characteristics and optical characteristics, as indicated by the absorbance and transmittance as a function of wavelength were calculated. Additionally, the energy gap was computed. The electrical conductivity of the DC in the various conduction zones was calculated by measuring the current and voltage as a function of temperature. Additionally, the mathematical equations are used to compute the energy constants, electron hopping distance, tail width, pre-exponential factor, and density of the energy states in variation zones (densities of the energ

The main purpose of this work is the construction of an optical parametric amplifier (OPA) to generate a 629 nm pulsed laser. KTP nonlinear crystals were used for both parametric oscillation and amplification. A singly resonant parametric oscillator (OPO) is constructed to generate a signal of 1.54 μm and idler of 3.4 μm when the OPO system is pumped by 1.064 μm Q – switched Nd: YAG laser. The signal was then mixed with the pumping beam in OPA system to form the wanted wavelength. The obtained optical conversion efficiency was 60%.

Femtosecond laser pulse propagation in monomode optical fibers is demonstrated and investigated numerically (by simulations) and experimentally in this paper. A passively mode locked Nd:glass laser giving a pulse duration of about 200 fsec at 1053 nm wavelength and 120 mW average optical power with 100 MHz repetition rate is used in the experimental work. Numerical simulations are done by solving the nonlinear Schrödinger equation with the aid of Matlab program. The results show that self phase modulation (SPM) leads to compression of the spectral width from 5 nm to 2.1 nm after propagation of different optical powers (34, 43, 86 and 120 mW) in fibers of different length (5, 15, 35 m). The varying optical powers produced a varying

In this research, optical absorption data (the imaginary part of the dielectric function Ɛ2 as a function of photon energy E) were re-analyzed for three samples of a-Si:H thin films using derivative methods trying to investigate the ambiguity that accompany the interpretation of the optical data of these film in order to obtainm the optical energy gap (Eg) and the factor (r) which in concerned with the density of state distribution near the mobility edge directly without the need for a pre- assumption for the factor r usually followed in traditional methods such as the Tauc plot. The derivative method was used for two choices for the factor q (which in connected with the dependence of the dipole matrix element on the photon energy ) for