Preferred Language
Articles
/
tBbXlYcBVTCNdQwCZVa4
Threshold Current Density of Al0.1Ga0.9N/GaN Triple Quantum Well Laser
...Show More Authors

Semiconductor laser is used in processing many issues related to the scientific, military, medical, industrial and agricultural fields due to its unique properties such as coherence and high strength where GaN-based components are the most efficient in this field. Current technological developments mention to the strong connection of GaN with sustainable electronic and optoelectronic devices which have high-efficiency. The threshold current density of Al0.1Ga0.9N/GaN triple quantum well laser structure was investigated to determine best values of the parameters affecting the threshold current density that are well width, average thickness of active region, cavity length, reflectivity of cavity mirrors and optical confinement factor. The optimum value of the threshold current density is 2670 A/cm2 was obtained when the well width (w= 2.5 nm), reflectivity of cavity mirrors (R1=0.75, R2=0.9), cavity length (L=2mm), average thickness of active region (d= 11.5 nm), and optical confinement factor ( Γ= 0.034) at room temperature.

Scopus Clarivate Crossref
View Publication
Publication Date
Wed Mar 10 2021
Journal Name
Baghdad Science Journal
Study the Effect of solvent on the Optical Properties Performance of active polymeric laser media
...Show More Authors

The paper include studies the effect of solvent of dye doped in polymeric laser sample which manufactured in primo press way, which is used as an active (R6G) tunable dye lasers. The remarks show that, when the viscosity of the solvent (from Pure Water to Ethanol), for the same concentration and thickness of the performance polymeric sample is increased, the absorption spectrum is shifts towards the long wave length (red shift), & towards short wave length (blue shift) for fluorescence spectrum, also increased the quantum fluorescence yield. The best result we obtained for the quantum fluorescence yield is (0.882) with thickness (0.25mm) in Ethanol solvent in concentration (2*10-3mole/liter), while when we used the Pure Water as a solvent,

... Show More
View Publication Preview PDF
Crossref
Publication Date
Wed Mar 18 2020
Journal Name
Baghdad Science Journal
Effect of CO2 Laser Irradiation on the Topographic and Optical Properties of CdO Thin Films
...Show More Authors

     In this study, cadmium oxide (CdO) was deposited on glass bases by thermal chemical spraying technique at three concentrations (0.05, 0.1, 0.15) M and then was irradiated by CO2 laser with 10.6 μm wave length and 1W power. The results of the atomic force microscope AFM test showed that the surfaces of these CdO thin films were homogenous and that the laser irradiated effect resulted in decreasing the roughness of the surface as well as the heights of the granular peaks, indicating a greater uniformity and homogeneity of the surfaces. The optical properties were studied to determine laser effect. The results of optical tests of these thin films showed that the photoluminescence spectra and absorption s

... Show More
View Publication Preview PDF
Scopus (7)
Crossref (2)
Scopus Clarivate Crossref
Publication Date
Sun Mar 06 2011
Journal Name
Baghdad Science Journal
Stimulation of Hatching Efficiency in Capsulated Cysts of Artemia fransiscana Using 890 nm Diode Laser
...Show More Authors

Artemia fransiscana is one of the most important live food for commercial larval aquaculture. The aim of this study is to investigate the effects of 890 nm diode laser irradiation on Artemia capsulated cysts using (1-10) minutes exposure time, and 2.26x10-3 J/cm2 Fluence. The Artemia samples were obtained from two locations: Dyalaa and Basraa. After irradiation, hatching percentage (H %) and hatching efficiency(HE) of Artemia were measured after 24 and 48 hours of incubation. The results of the effect of laser light on the capsulated cysts from Dyalaa showed that the optimum dose for enhancing (H %) after 24 hours of incubation is using 10 minutes exposure time, while after 48 hours of incubation the (H %) enhancement can be achieved

... Show More
View Publication Preview PDF
Crossref
Publication Date
Thu Dec 01 2011
Journal Name
Iraqi Journal Of Physics
Effect of thermal annealing and laser radiation on the optical properties of AgAlS2 thin films
...Show More Authors

Effect of the thermal annealing at 400oC for 2 hours and Argon laser radiation for half hour on the optical properties of AgAlS2 thin films, prepared on glass slides by chemical spray pyrolysis at 360oC with (0.18±0.05) μm thickness .The optical characteristics of the prepared thin films have been investigated by UV/Vis spectrophotometer in the wavelength range (300 – 1100)nm .The films have a direct allow electronic transition with optical energy (Eg) values decreased from (2.25) eV for untreated thin films to (2.10) eV for the annealed films and to (2.00) eV for the radiated films. The maximum value of the refractive index (n) for all thin films are given about (2.6). Also the extinction coefficient (K) and the real and imaginary d

... Show More
View Publication Preview PDF
Publication Date
Sun Feb 03 2019
Journal Name
Journal Of The College Of Education For Women
Improvement of the surface hardness and wear resistant of low carbon steel using laser radiation
...Show More Authors

0

View Publication Preview PDF
Publication Date
Sun Jan 01 2006
Journal Name
Journal Of Cosmetic And Laser Therapy
Use of the pulsed infrared diode laser (904 nm) in the treatment of alopecia areata
...Show More Authors

View Publication
Scopus (53)
Crossref (56)
Scopus Crossref
Publication Date
Sun Dec 01 2019
Journal Name
Al-khwarizmi Engineering Journal
Effect of Laser Shock Peening on the Fatigue Behavior and Mechanical Properties of Composite Materials
...Show More Authors

In this study, Laser Shock Peening (LSP) effect on the polymeric composite materials has been investigated experimentally. Polymeric composite materials are widely used because they are easy to fabricate and have many attractive features. Unsaturated polyester resin as a matrix was selected and Aluminum powder with micro particles as a reinforcement material was used with different volume fraction (2.5%, 5% and 7.5%). Hand lay-up process was used for preparation the composites. Fatigue test with constant amplitude with stress ratio (R =-1) was carried out before and after LSP process with two levels of energy (1Joule and 2Joule). The result showed an increase in the endurance strength of 25.448% at 7.5% volume fraction when peened is 1J

... Show More
View Publication Preview PDF
Crossref
Publication Date
Wed Nov 12 2025
Journal Name
Journal Of Baghdad College Of Dentistry
Bone density determination for the maxilla and the mandible in different age groups by using computerized tomography (Part I)
...Show More Authors

Background: Mini implant stability is primarily related to local bone density; no studies have evaluated bone density related to mini implant placement for orthodontic anchorage between different age groups in the maxilla and the mandible. The present research aims to evaluate side, gender, age, and regional differences in bone density of the alveolar bone at various orthodontic implant sites. Materials and method: Fifty three individuals who were divided into two groups according to their age into: group I (ages 16-20 years) and group II (ages 21-29 years) had subjected to clinical examination, then 64-multislice computed tomography scan data were evaluated and bone density was measured in Hounsfield unit at 102 points (51 in the maxilla

... Show More
View Publication Preview PDF
Publication Date
Sat Jun 01 2013
Journal Name
Journal Of Economics And Administrative Sciences
Comparison between some well- Known methods to estimate the parameter of the proposed method of measurement and the reliability of the distribution function with two parameters Rally by simulation
...Show More Authors

 

 

Abstract

            Rayleigh distribution is one of the important distributions used for analysis life time data, and has applications in reliability study and physical interpretations. This paper introduces four different methods to estimate the scale parameter, and also estimate reliability function; these methods are Maximum Likelihood, and Bayes and Modified Bayes, and Minimax estimator under squared error loss function, for the scale and reliability function of the generalized Rayleigh distribution are obtained. The comparison is done through simulation procedure, t

... Show More
View Publication Preview PDF
Crossref
Publication Date
Wed May 10 2023
Journal Name
Journal Of Planner And Development
The impact of population density in sustainable housing - An applied study in the city of Baghdad (Mahalla 817), Al-Bayaa as a model
...Show More Authors

Population density represents an important indicator for determining the growth of the size of urban areas. Population density has a direct impact on the quality of life, and its excessive rise may lead to the deterioration of basic service facilities. The problem of the research is that the increase in the total population densities of the residential neighborhood may reflect negatively on the nature of the services provided to the residents in these shops, and thus the failure to achieve sustainability in the residential locality. The research assumes that the increase in population densities negatively affects the achievement of sustainability in the residential neighborhood.

 

      

... Show More
View Publication Preview PDF