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Optimization Procedures using Effect of Etalon Finesse and Driving Term on Optical Bistability

        In this work, analytical study for simulating a Fabry-Perot bistable etalon (F-P cavity) filled with a dispersive optimized nonlinear optical material (Kerr type) such as semiconductors Indium Antimonide (InSb). Because of a trade off between the etalon finesse values and driving terms, an optimization procedures have been done on the InSb etalon/CO laser parameters, using critical switching irradiance (Ic) via simulation systems of optimization procedures of optical cavity. in order to achieve the  minimum switching power and faster switching time, the optimization parameters of the finesse values and driving terms on optical bistability and switching dynamics must be studied.

        In addition, for different values of a cavity finesse (for example, F = 25 and 2.37) the switching intensity takes low values with a high finesse etalon compared to a high switching intensity with a low finesse etalon. So, the minimum switching power for a low finesse etalon is ⁓0.785mW, and is about 0.0785mW for a high finesse etalon. The driving term peak of a high finesse etalon becomes higher and the slowing down region becomes less, leading to a fast switching as compared with a slow switching in a low finesse etalon. So that, the minimum switching time was about 300ns for a low finesse etalon, and about 150ns for a high finesse etalon.

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Publication Date
Wed Oct 01 2014
Journal Name
Journal Of The Faculty Of Medicine Baghdad
Bone Marrow Procedures in Children Welfare Teaching Hospital/Medical City Complex Indications and results

Background: Bone marrow aspiration (BMA) and biopsy is a procedure that is used to evaluate the cause of abnormal blood test results, to confirm a diagnosis or check the status of severe anemia of unknown cause, to evaluate abnormalities in the blood's ability to store iron and also to diagnose infection.

Objectives: To identify the main indications of bone marrow aspiration and the most common diagnoses encountered in children welfare teaching hospital.

Patients and methods: This was a prospective and retrospective descriptive study over 6- month period from 8th of February 2010 to 8th of August 2010 in children younger than 14 years. All bone marrow aspirate results wer

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Publication Date
Tue Nov 01 2022
Journal Name
Chemical Methodologies
Study of Optical and Structural Properties of CdTe Quantum Dots Capped with 3MPA Using Hydrothermal Method

Quantum dots (QDs) can be defined as nanoparticles (NPs) in which the movement of charge carriers is restricted in all directions. CdTe QDs are one of the most important semiconducting crystals among other various types where it has a direct energy gap of about 1.53 eV. The aim of this study is to exaine the optical and structural properties of the 3MPA capped CdTe QDs. The preparation method was based on the work of Ncapayi et al. for preparing 3MPA CdTe QDs, and hen, the same way was treated as by Ahmed et al. via hydrothermal method by using an autoclave at the same temperature but at a different reaction time. The direct optical energy gap of CdTe QDs is between 2.29 eV and 2.50 eV. The FTIR results confirmed the covalent bonding betwee

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Publication Date
Wed Jun 01 2022
Journal Name
Chalcogenide Letters
Influence of Al dopant on structural and optical parameters of AgInSe2 thin film

Chalcopyrite thin films ternary Silver Indium Diselenide AgInSe2 (AIS) pure and Aluminum Al doped with ratio 0.03 was prepared using thermal evaporation with a vacuum of 7*10-6 torr on glass with (400) nm thickness for study the structural and optical properties. X-ray diffraction was used to show the inflance of Al ratio dopant on structural properties. X-ray diffraction show that thin films AIS pure, Al doped at RT and annealing at 573 K are polycrystalline with tetragonal structure with preferential orientation (112). raise the crystallinity degree. AFM used to study the effect of Al on surfaces roughness and Grain Size Optical properties such as the optical band gap, absorption coefficient, Extinction coefficient, refractive ind

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Publication Date
Wed Oct 20 2021
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Dynamics and its Effects on Saturation Region in Semiconductor Optical Amplifiers

We focus on studying the dynamics of bulk semiconductor optical amplifiers and their effects on the saturation region for short pulse that differ, however there is the same unsaturated gain for both dynamics. Parameters like current injection, fast dynamics present by carrier heating (CH), and spectra hole burning (SHB) are studied for regions that occur a response to certain dynamics. The behavior of the saturation region is found to be responsible for phenomena such as recovery time and chirp for the pulse under study.

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Publication Date
Fri Sep 29 2023
Journal Name
Pakistan Journal Of Ophthalmology
Corneal Parameters Measurement in Healthy Subjects Using Scheimpflug and Anterior Segment Optical Coherence Tomography

Purpose:  To compare the central corneal thickness (CCT),minimum corneal thickness (MCT) and corneal power measured using theScheimpflug-Placido device and optical coherence tomography (OCT) in healthy eyes. Study Design:  Descriptive observational. Place and Duration of Study:  Al-Kindy college of medicine/university of Baghdad, from June 2021 to April 2022. Methods:  A total of 200 eyes of 200 individuals were enrolled in this study. CCT and MCT measurements were carried out using spectral-domain optical coherence tomography (Optovue) and a Scheimpflug-Placido topographer (Sirius).The agreement between the two approaches was assessed using Bland-Altman analysis in this study. Results:  Mean age was 28.54 ± 6.6 years, me

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Publication Date
Sun Sep 01 2019
Journal Name
Journal Of Global Pharma Technology
Calculation of Stabilization Energy of Tetrahedrane with its Nitrogen Substituted Derivatives by DFT Method and Driving an Empirical Relation Connect it with Charge Functions of the Molecule

In this work the strain energy of tetrahedrane and its nitrogen substituted molecules were calculated by isodesmic reaction method according to DFT quantum chemical fashion, the used basis set was 6-31G/B3-LYP, in addition all structures were optimized by RM1 semi-empirical method. From the obtained data we estimate an empirical equation connect between strain energy of the molecule with charge functions represented by dipole moment of the molecule plus accumulated charge density involved within the tetrahedron frame plus the number of nitrogen atoms. The results indicate the charge spreading factors by polarization and processes are the most important factors in decreasing the strain energy.

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Publication Date
Sun Dec 31 2017
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Study the Effect of Using Microwave Radiation and H-Donors on Improving Heavy Oil

The present research has investigated the effect of microwave energy on improving the flow properties of heavy crude oil. The fragmentation of crude oil molecules was carried out with and without using 1 and 10 wt. % concentration of various types of H-donors like tetralin, cyclohexane, and naphtha.  Microwave power of 320, 385, and 540 W and radiation time 1-9 min, and temperature were studied. The kinematic viscosity and asphaltene content were measured for evaluation the improving of heavy crude oil.

   Results show that viscosity of crude oil decreased with increase H-donor concentration, a maximum percentage of viscosity reduction was10.63 % for tetralin at 6 min radiation time, while 8.67%, and 7.34% for cycl

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Publication Date
Thu Oct 01 2015
Journal Name
Journal Of Engineering
Modeling and Optimization the Influence of CO2-MAG Welding Parameters on the Weld Joint Shape Factors

This paper represents an experimentalattempt to predict the influence of CO2-MAG welding variables on the shape factors of the weld joint geometry. Theinput variables were welding arc voltage, wire feeding speed and gas flow rate to investigate their effects on the shape factorsof the weld joint geometry in terms of weld joint dimensions (bead width, reinforcement height, and penetration). Design of experiment with response surface methodology technique was employed to buildmathematical models for shape factors in terms of the input welding variables. Thepredicted models were found quadratic type and statistically checked by ANOVA analysis for adequacy purpose. Also, numerical and graphical optimizations were carried out

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Publication Date
Sun Apr 29 2012
Journal Name
Journal Of Karbala University
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Publication Date
Wed Dec 25 2019
Journal Name
Journal Of Engineering
Corrosion Rate Optimization of Mild-Steel under Different Cooling Tower Working Parameters Using Taguchi Design

This study investigates the implementation of Taguchi design in the estimation of minimum corrosion rate of mild-steel in cooling tower that uses saline solution of different concentration. The experiments were set on the basis of Taguchi’s L16 orthogonal array. The runs were carried out under different condition such as inlet concentration of saline solution, temperature, and flowrate. The Signal-to- Noise ratio and ANOVA analysis were used to define the impact of cooling tower working conditions on the corrosion rate. A regression had been modelled and optimized to identify the optimum level for the working parameters that had been founded to be 13%NaCl, 35ᴼC, and 1 l/min. Also a confirmation run to establish the p

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