Preferred Language
Articles
/
bsj-6822
A Study of a-Si:H Absorption Edge Using Dunstan’s Model
...Show More Authors

The optical absorption data of Hydrogenated Amorphous Silicon was analyzed using a Dunstan model of optical absorption in amorphous semiconductors. This model introduces disorder into the band-band absorption through a linear exponential distribution of local energy gaps, and it accounts for both the Urbach and Tauc regions of the optical absorption edge.Compared to other models of similar bases, such as the O’Leary and Guerra models, it is simpler to understand mathematically and has a physical meaning. The optical absorption data of Jackson et al and Maurer et al were successfully interpreted using Dunstan’s model. Useful physical parameters are extracted especially the band to the band energy gap , which is the energy gap in the absence of disorder, that can be interpreted as the mobility gap of the material.

Scopus Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Thu Jan 01 2015
Journal Name
Political Sciences Journal
Fiscal federalism: a study of the concept and models
...Show More Authors

يمثل الأخذ بالنظام الفيدرالي أطاراً تنظيمياً لشكل الدولة و مرحلة تحول مهمة في بنية الدولة العامة في مختلف مجالاتها، فالانتقال من المركزية في أدارة الشؤون العامة للدولة الى النمط الفيدرالي يمثل تحولا بنيوياً وسيكولوجياً ،حيث يكون هنالك توزيع مكاني - عمودي للسلطة والثروة بين الوحدات المكونة للدولة بشكل يختلف كليا عن الحالة المركزية، ونجد صور تنظيمية عديدة تتأسس ضمن اطار الفيدرالية العام ،

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sat Sep 23 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
A Study of using Mesocyclops hyalinus and Cyclops agilis as A biological Control of Anophles larvae
...Show More Authors

The fresh water ecosystem constitute an essential and very important for human life, for this reason it should be kept away from all the chemical pollutants including the pesticides The best way for Fighting harmful insects.(such as Anophles larvae) is by the biological control.

 

In the present study two species of Cyclopoida: Copepod, Mesocyclops hyalinus and Cyclops agilis Ø¢ were used as predators for Anophles larvae.

 

The data showed that the percentages of predation were 65% and 56%

forM. hyalinus and C. agilis respectively

 

and the means of predation were 1.3 larvae/ female and 1.1

... Show More
View Publication Preview PDF
Publication Date
Sun Aug 06 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Computer Analysis Of A simplified Eye Model
...Show More Authors

  Computer analysis of simple eye model is performed in the present work by using the Zemax optical design software 2000E . The most important optical parameters of the eye were calculated such as the effective focal length (EFL) , the image spot size at the retina and found to be in a reasonable agreement with the values needed for the laser retinal treatment .The present eye model leads to an effective wavelength and we found the image spot diagram at the surface of the retina and the wavefront error which are provided at zero field angle. This gives a good evidence of the validity of the model in one hand, and can be used to determine the compatibility of any optical design intended for visual applications. By using the pulse fre

... Show More
View Publication Preview PDF
Publication Date
Sat Oct 28 2023
Journal Name
Baghdad Science Journal
Experimental Investigation of the Mechanical and Structural Properties of a Functionally Graded Material by Adding Alumina Nanoparticles Using A Centrifugal Technique
...Show More Authors

In this work, functionally graded materials were synthesized by centrifugal technique at different
volume fractions 0.5, 1, 1.5, and 2% Vf with a rotation speed of 1200 rpm and a constant rotation time, T
= 6 min . The mechanical properties were characterized to study the graded and non-graded nanocomposites
and the pure epoxy material. The mechanical tests showed that graded and non-graded added alumina
(Al2O3) nanoparticles enhanced the effect more than pure epoxy. The maximum difference in impact strength
occurred at (FGM), which was loaded from the rich side of the nano-alumina where the maximum value was
at 1% Vf by 133.33% of the sample epoxy side. The flexural strength and Young modulus of the fu

... Show More
View Publication Preview PDF
Scopus (4)
Crossref (2)
Scopus Crossref
Publication Date
Tue Sep 01 2009
Journal Name
Journal Of Economics And Administrative Sciences
Evaluating the quality of educational services according to the modified Servqual modelStudy of a sample of students of the Faculty of Management and Economics / University of Baghdad
...Show More Authors

The research aims to apply a modified SERVQUAL model to evaluate the quality of the educational services via conducting exploratory research for students from the College of Administration and Economics- Department of Business Administration- Evening studies at the University of Baghdad. Questionnaire of two parts was distributed to a sample of (72) students out of (720) students of the 2nd.,3rd. and 4th. year in the beginning of the second semester of the year 2008-2009 to measure the expectations and perceptions to the quality of the educational services. Five major dimensions were analyzed to see the gaps for (22) variables. The study concluded that there were (13) variables confirmed that the

... Show More
View Publication Preview PDF
Crossref
Publication Date
Fri Apr 01 2022
Journal Name
Baghdad Science Journal
Iron (II) Determination in Lipstick Samples using Spectrophotometric and Microfluidic Paper-based Analytical Device (µPADs) Platform via Complexation Reaction with Iron Chelator 1, 10-phenanthroline: A Comparative Study
...Show More Authors

This study was undertaken to introduce a fast, accurate, selective, simple and environment-friendly colorimetric method to determine iron (II) concentration in different lipstick brands imported or manufactured locally in Baghdad, Iraq. The samples were collected from 500-Iraqi dinars stores to establish routine tests using the spectrophotometric method and compared with a new microfluidic paper-based analytical device (µPAD) platform as an alternative to cost-effective conventional instrumentation such as Atomic Absorption Spectroscopy (AAS). This method depends on the reaction between iron (II) with iron(II) selective chelator 1, 10-phenanthroline(phen) in the presence of reducing agent hydroxylamine (HOA) and sodium acetate (NaOAc) b

... Show More
View Publication Preview PDF
Scopus (7)
Crossref (3)
Scopus Clarivate Crossref
Publication Date
Sat Dec 01 2018
Journal Name
Al-khwarizmi Engineering Journal
Biodegradation of Diesel Contaminated Soil Using Single Bacterial Strains and a Mixed Bacterial Consortium
...Show More Authors

This study was conducted to assess the hydrocarbon degradation abilities of Sphingomonas paucimobilis, Pentoae species, Staphylococcus aureus, and Enterobacter cloacae, which isolated from diesel contaminated soil samples. Single strains and mixed bacterial consortia have been investigated their ability to degrade 1.0 % (v/v) of diesel oil in Bushnell- Haas medium as sole.carbon.and.energy.source. At temperature 30C, the individual.bacterial.isolates exhibited low growth and low degradation.than did the.mixed. bacterial.culture. After 28 days.of incubation the.combination.of four isolates degraded.an upper limit.of diesel  88.4%. This was. continued.by 85.1% by S. paucimobilis, 84 % by Pentoae sp., 79% by S.aureus, and

... Show More
View Publication Preview PDF
Publication Date
Sun Mar 01 2020
Journal Name
Journal Of Engineering
The effect of titanium oxide microparticles on mechanical properties, absorption and solubility processes of a glass ionomer cement
...Show More Authors

Glass Ionomer Cement (GIC) is one of the important dental temporary filing materials. The aim of this study is to evaluate the effect of adding 3, 5 and 7 wt. % of TiO2 microparticles to conventional GIC powder (Riva Self Cure) on mechanical properties and its effect on absorption and solubility processes. TiO2 particles additives improved compressive strength and biaxial flexural strength, where the compressive strength increased with increasing in the added ratio, while the highest value of the biaxial flexural strength was at 3 wt.%. The addition of TiO2 particles improved the surface Vickers microhardness values, with highest value at 5 wt. %. On other hand TiO2 addition im

... Show More
View Publication Preview PDF
Crossref (2)
Crossref
Publication Date
Tue Dec 05 2023
Journal Name
Baghdad Science Journal
A Novel System for Confidential Medical Data Storage Using Chaskey Encryption and Blockchain Technology
...Show More Authors

Secure storage of confidential medical information is critical to healthcare organizations seeking to protect patient's privacy and comply with regulatory requirements. This paper presents a new scheme for secure storage of medical data using Chaskey cryptography and blockchain technology. The system uses Chaskey encryption to ensure integrity and confidentiality of medical data, blockchain technology to provide a scalable and decentralized storage solution. The system also uses Bflow segmentation and vertical segmentation technologies to enhance scalability and manage the stored data. In addition, the system uses smart contracts to enforce access control policies and other security measures. The description of the system detailing and p

... Show More
View Publication Preview PDF
Scopus (2)
Scopus Crossref
Publication Date
Wed Sep 30 2020
Journal Name
College Of Islamic Sciences
Saba is a semantic study of examples of pronouns
...Show More Authors

which is much useful in the Arabic Language generally in the Holly Quran especially. It is the pronoun  I have taken in the semantic aspect from it and I have done on the surra sabba which varities  the semantical pronoun in it among the pronoun of the speaker the conscience of the addressee the absent  such the the siprat pronoun that comes in it with the explanation for its importance and its work and this is the subject of the first unit which I advanced it from the concept of the pronoun Linguistically and convention. After that I have lighten in some meanings which I have done in the surrat as a semantic , magnification , proud, reprimand and others which I ended my research I have reached the results from it

... Show More
View Publication Preview PDF