In this work, the effects of size, and temperature on the linear and nonlinear optical properties in InGaN/GaN inverse parabolic and triangular quantum wells (IPQW and ITQW) for different concentrations at the well center were theoretically investigated. The indium concentrations at the barriers were fixed to be always x_max = 0.2. The energy levels and their associated wave functions are computed within the effective mass approximation. The expressions of optical properties are obtained analytically by using the compact density-matrix approach. The linear, nonlinear, and total absorption coefficients depending on the In concentrations at the well center are investigated as a function of the incident photon energy for different

Iraqi kaolin was used for the preparation and characterization of NaY zeolite for biodiesel production via esterification reaction. Oleic acid was used usually as a typical simulated feedstock of high acid number for the esterification reaction.

   The chemical composition for the prepared Nay zeolite is as following:  (Ca₂.6Na₁.K_0.1)(Al₆.3Si₁₇.₇)O₄₈.16H₂O, the silica to alumina ratio in the prepared catalyst was found equal to 2.6 and Na₂O content was 12.26 wt. %, with relative crystallinity equal to 147.4 % obtained by the X-ray diffraction. The surface area result shows that the prepared catalyst has 330 m²

Abstract

 Nano-crystalline ZSM-5 zeolite was synthesized by hydrothermal method using chelating agent and two gel compositions:Compositionɪ:Al₂O₃:86SiO₂:5.5TPA:12.7Na₂O:3.4Trien:3320H₂O.Compositionɪɪ:Al₂O₃:68SiO₂:5.4TPA:10Na₂O:2.6Trien:2626H₂O.Study of hydrothermal reaction factors on characteristics of nano- sized zsm-5 has been carried on ,among them are crystallization temperature, crystallization time and concentration of template ( TPAOH ) solution. Synthesis was accomplished in PTFE lined autoclave ( reactor ) . The product were characterized by X-ray diffraction ( XRD ),Atomic force microsc

 The internal administrative spaces of the interior designer formed an obsession for their development and for finding solutions and treatments to advance to enhance the state of adaptation for their employees by providing a healthy, appropriate and sound environment for work and production. . The first chapter focuses on laying theoretical foundations to show what health materials are used in the administrative spaces of the training directorates of the Ministry of Education in Baghdad. The second chapter dealt with the knowledge of health materials, their impact and effectiveness in the interior space, and the variables of their functional characteristics and their work in the interior spaces in a way that enhances the development of

In this work ,pure and doped(CdO)thin films with different concentration of V2O5x (0.0, 0.05, 0.1 ) wt.% have been prepared on glass substrate at room temperature using Pulse Laser Deposition technique(PLD).The focused Nd:YAG laser beam at 800 mJ with a frequency second radiation at 1064 nm (pulse width 9 ns) repetition frequency (6 Hz), for 500 laser pulses incident on the target surface At first ,The pellets of (CdO)1-x(V2O5)x at different V2O5 contents were sintered to a temperature of 773K for one hours.Then films of (CdO)1-x(V2O5)x have been prepared.The structure of the thin films was examined by using (XRD) analysis..Hall effect has been measured in orded to know the type of conductivity, Finally the solar cell and the effici

In this work, the effect of different particle size on the nonlinear optical properties of silver nanoparticles in de-ionized water was studied. The experimental observation of the far field diffraction patterns by CCD camera in two and three dimensions. The maximum change of nonlinear refractive index and the relative phase shift were calculated. The self-defocusing technique was used with a continuous-wave radiation from DPSS Blue laser .The wavelength is 473 nm with an output power of 270 mW. All the Ag colloids samples containing the sizes 15, 30, 50, and 70 nm of silver nanoparticles used in the study were chemically prepared. It was found that the nonlinear refractive index is a particle size dependent and of the order of 10-7 cm2/