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Optimization Procedures using Effect of Etalon Finesse and Driving Term on Optical Bistability
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        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
Sun Mar 17 2019
Journal Name
Baghdad Science Journal
Studying the Flux Density of Bright Active Galaxies at Different Spectral Bands
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Statistical studies are reported in this article for an active galactic nuclei sample of different type of active galaxies Seyferts 1, Seyferts 2, and Quasars. These sources have been selected from a Catalogue for bright X-ray galaxies. The name of this index is ROSAT Bright Source Catalogue (RBSC) and the NRAO VLA Sky Survey (NVSS). In this research, multi-wavelength observational bands Radio at 1.4 GHz, Optical at 4400 A0, and X-ray at energy 0.1-2.4 KeV have been adopted in this study. The behavior of flux density ratios has been studied ,  with respect to the absolute magnitude . Furthermore, the Seyfert1 and Seyfert 2 objects are combined in one group and the QSOs are collectest in another group. Also, it has been found that t

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Publication Date
Mon Mar 27 2023
Journal Name
Iranian Journal Of Materials Science And Engineering
First-Principles Analysis of Cr-Doped SrTiO 3 Perovskite as Optoelectronic Materials
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The influence of Cr3+ doping on the ground state properties of SrTiO 3 perovskite was evaluated using GGA-PBE approximation. Computational modeling results infered an agreement with the previously published literature. The modification of electronic structure and optical properties due to Cr3+ introducing into SrTiO 3 were investigated. Structural parameters assumed that Cr3+ doping alters the electronic structures of SrTiO 3 by shifting the conduction band through lower energies for the Sr and Ti sites. Besides, results showed that the band gap was reduced by approximately 50% when presenting one Cr3+ atom into the SrTiO 3 system and particularly positioned at Sr sites. Interestingly, substituting Ti site by Cr3+ led to eliminating the ban

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Publication Date
Sun Mar 07 2010
Journal Name
Baghdad Science Journal
Study the Level of Service to Roadways which Leading to Basrah University
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The building of Basrah University located in a rural area at Gramat Ali, its consist of seven colleges and very high number of students, lecturers ,and employers. Therefore, the intersections which leading to university building suffer congestion at morning peak hour (8-9) A.M and evening peak hour (2-3) P.M. In this study we collected the data in intersections which leading to university building at peak hour at same time, then we had analysis this data by using the highway capacity manual (HCM) and program (HCS). Also, we collected that data in University entries with classification of vehicles according to types and number of passengers at peak hour. Then we studied the number of proposals to riddance the congestion, such as the effe

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Publication Date
Fri Dec 01 2023
Journal Name
Caspian Journal Of Environmental Sciences
Assessment of indoor air quality for closed cafés in Baghdad City, Iraq
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The phenomenon of young people frequenting closed cafes spread in Baghdad to smoke hookahs and cigarettes has increased. This phenomenon is associated with unemployment, an increase in leisure time and the deterioration of economic conditions. This phenomenon has an impact on indoor air quality and exposes workers to the risk of exposure to various pollutants, including particulate matter, therefore, we examined some indicators (PM2.5, PM10) IAQ for a month in summer and another month in winter in six different locations in the Rusafa district. PM2.5 and PM10 concentrations, relative humidity (RH) and temperatures were measured using (Multifunction Air Quality Detector BENETECH -China). The results showed an increase in temperatures inside

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Publication Date
Thu Dec 01 2022
Journal Name
Wiadomości Lekarskie
EVALUATION OF TWO CRYOPROTECTANTS USED IN A NEW HUMAN SPERM CRYOPRESERVATION TECHNIQUE
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The aim: To examine the efficiency of different concentrations of Dimethyl sulfoxide (DMSO) and glycerol as a cytoprotectants in protection of human sperms during cryopres¬ervation in this technique. Materials and methods: Thirty oligozoospermic semen samples were used in this study. Samples diagnosed according to WHO 2010 criteria. Sheep’s ovarian follicles obtained from local slaughterhouse and prepared by slicing the ovaries and evacuating the follicular fluid and oocyte. Each semen sample divided into six equal parts, and diluted 1:1 with cryosolution contains 5%, 10%, 15% DMSO or glycerol and injected within the emptied follicles. After freezing and thawing, the semen mixture aspired outside the follicles and sperm concentr

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Publication Date
Tue Jun 15 2021
Journal Name
Al-academy
Rhetorical connections to the head-covers of Mesopotamian gods: جهينة حامد حساني
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The Rafidian artist discussed the headdresses of his idols with a varied scholarly momentum, so each idol had its own cover as this door of diversity contributed to the enrichment of Rafidian thought and full knowledge of their ideas and beliefs consistent with their multiple symbolic connections such as architecture, for example. The previous one, if not its entirety.
A research such as this (the discursive connections to the head-covers of the deities of the Mesopotamian civilization) aims to clarify the confusion that occurs through four chapters: The first chapter included: the research problem, the importance of research and the need for it, the objectives of the research, the temporal, spatial and objective limits of research, a

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Publication Date
Wed Dec 30 2020
Journal Name
Journal Of Planner And Development
Urban improvement, a mechanism of tourism development: Tébessa (Algeria) as a model
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The tourism industry has become, currently, an art, an industry and a science. It is also one of the components that make up touristic regions. Tourist attractions are no longer the exclusive visits of museums and archeological sites, but also involve other service facilities. It is, therefore, imperative that the authorities should become aware of the degradation of tourist resorts and prevent them from getting worse. Moreover, the authorities should take a set of decisions concerning the protection of the urban aspect with its historical, social, and environmental dimensions, as well as, adapting it to the modern requirements that can bring comfort to the citizens and tourists at physical and psychological levels.

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Publication Date
Wed Mar 30 2022
Journal Name
Journal Of Educational And Psychological Researches
Science Processes Included in the Teacher's Handbook of Middle School Science Experiments
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The aim of this research is to uncover the science processes included in the teacher’s guide to scientific experiments for science books for grades (first-second) for the intermediate stage, The research sample included all the scientific experiments contained in the teacher’s guide for scientific experiments for the intermediate stage, The researcher used the descriptive and analytical method, and designed an analysis tool, The content of science operations, and verified its validity and consistency, and after using percentages and ranks for statistical treatment, the research reached the following results: The number of practical experiments varies from one class to another in the intermediate stage, where the highest percentage ap

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Publication Date
Wed Oct 05 2016
Journal Name
Al-academy
The Stylistic Development in the Crafts of the Sculptor Mohammed Ghani Hikmat
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The present study aims at examining the stylistic development in the crafts of the sculptor Mohammed Ghani Hikmat. It gives answers to the following two questions: what is the nature of the stylistic development? And what are these principles and techniques led him to this development? The researcher has used the descriptive, analytic approach in examining the selected five samples out of the sculptor’s displayed crafts. The observational technique is used as a tool of examination. Among the main findings are: integrating space in the cubic crafts, represented by the existence of holes within this general construction of that space; the evident influence of critical contemporary orientations through the direct insertion of recipients i

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Publication Date
Sun Mar 01 2009
Journal Name
Al-khwarizmi Engineering Journal
Mass Transfer Coefficient During Cathodic Protection of Low Carbon Steel in Seawater
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The aim of this research is to calculate mass transfer coefficient, kd, during cathodic protection of low carbon steel in neutral seawater (3.5% W/V NaCl in distilled water with pH = 7). Two types of cathodic protection were used:

First: Sacrificial anode cathodic protection (SACP) were a pipeline of steel carrying seawater  using zinc as a sacrificial anode and with variable temperatures ranged (0 – 45oC) and volumetric flow rate ranged (5 – 900 lit/hr). It was found that the kd increases with increasing temperature and volumetric flow rate of seawater, where kd ranged (0.24×10-6 – 41.6×10-6 m/s).

Second: Impressed current cathodic pr

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