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Study of the Optical Properties of 3MPA CdTe and 3MPA CdTe/CdSe Quantum Dots at PH 12 in Different Periods of Time
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This research aims to study the optical characteristics of semiconductor quantum dots (QDs) composed of CdTe and CdTe/CdSe core-shell structures. It utilizes the refluxed method to synthesize these nanoscale particles and aims to comprehend the growth process by monitoring their optical properties over varied periods of time and pH 12. Specifically, the optical evolution of these QDs is evaluated using photoluminescence (PL) and ultraviolet (UV) spectroscopy. For CdTe QDs, a consistent absorbance and peak intensity increase were observed across the spectrum over time. Conversely, CdTe/CdSe QDs displayed distinctive absorbance and peak intensity variations. These disparities might stem from irregularities in forming selenium (Se) layers around CdTe QDs during growth stages, which could potentially induce quenching in the emission spectrum. The optical examinations unveiled a discernible redshift towards higher wavelength values as the reaction progressed. This spectral shift was coupled with an enlargement in QDs size and a decrease in the energy gap. Using PL and UV analysis techniques enabled a comprehensive study of the optical attributes of the CdTe and CdTe/CdSe QD systems. Our findings underscored the influence of growth conditions and shell materials on the optical properties of QDs. The observed changes in absorbance, peak intensity, wavelength values, QDs size, and energy gap with increasing reaction time provided valuable insights into the growth dynamics of these QD structures.

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Publication Date
Tue Sep 01 2009
Journal Name
Journal Of Nonlinear Optical Physics & Materials
SPECTRAL WIDTH VARIATION OF ULTRASHORT LASER PULSES IN MONOMODE OPTICAL FIBERS
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Femtosecond laser pulse propagation in monomode optical fibers is demonstrated and investigated numerically (by simulations) and experimentally in this paper. A passively mode locked Nd:glass laser giving a pulse duration of about 200 fsec at 1053 nm wavelength and 120 mW average optical power with 100 MHz repetition rate is used in the experimental work. Numerical simulations are done by solving the nonlinear Schrödinger equation with the aid of Matlab program. The results show that self phase modulation (SPM) leads to compression of the spectral width from 5 nm to 2.1 nm after propagation of different optical powers (34, 43, 86 and 120 mW) in fibers of different length (5, 15, 35 m). The varying optical powers produced a varying

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Publication Date
Mon Oct 01 2018
Journal Name
Iraqi Journal Of Physics
Simulations of the initiation and propagation of streamers in electrical discharges inside water at 3 mm length gap
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This work is devoted to the modeling of streamer discharge, propagation in liquid dielectrics (water) gap using the bubble theory. This of the electrical discharge (streamer) propagating within a dielectric liquid subjected to a divergent electric field, using finite element method (in two dimensions). Solution of Laplace's equation governs the voltage and electric field distributions within the configuration, the electrode configuration a point (pin) - plane configuration, the plasma channels were followed, step to step. The results show that, the electrical discharge (streamer) indicates the breakdown voltage required for a 3mm atmospheric pressure dielectric liquid gap as 13 kV. Also, the electric potential and field distributions sho

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Publication Date
Mon Mar 08 2021
Journal Name
Baghdad Science Journal
A study the electrical properties of a Se:2.5%as thin films prepared by thermal cvaporation
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thin films of se:2.5% as were deposited on a glass substates by thermal coevaporation techniqi=ue under high vacuum at different thikness

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Publication Date
Fri Dec 01 2017
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Job enrichment, knowledge capital and its impact on strategic success: exploratory study at a sample of the Iraqi government and Private Colleges on Baghdad
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The problem of research was the lack of research that dealt with issue of the job design approach that is more suitable for knowledge work, therefore, the research aims to determine the impact of job enrichment,  and knowledge capitalon strategic success, starting from the hypothesis that there significant impact of job enrichment and knowledge capital on strategic success, to achieve this goal the researchers from the theoretical literature and  related studies conclude to the construction of the scheme shows the hypothetical relationship between the variables, which was adopted job enrichment as independent variable while knowledge capital plays two roles, the first as an independent variable and the second as an intermediate

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Publication Date
Thu Jun 27 2019
Journal Name
Bulletin Of The Iraq Natural History Museum (p-issn: 1017-8678 , E-issn: 2311-9799)
RECORD OF GYRODACTYLUS BYCHOWSKIANUS BOGOLEPOVA, 1950 (MONOGENEA, GYRODACTYLIDAE) FOR THE FIRST TIME IN IRAQ FROM GILLS OF THE CYPRINID FISH ARABIBARBUS GRYBUS
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The monogenean Gyrodactylus bychowskianus Bogolepova, 1950 is recorded in the present study for the first time in Iraq from the gills of the cyprinid fish Arabibarbus grypus (Heckel, 1843); which was collected from the Tigris River at Al-Taji Beach north of Baghdad Province during the period from July until November 2018.

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Publication Date
Sun Jun 05 2016
Journal Name
Baghdad Science Journal
Density functional theory study of molecular structure, Electronic properties, UV–Vis spectra on coumarin102.
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The various properties of the ground and excited electronic states of coumarins 102 using density functional theory (DFT) and time-dependent density functional theory (TDDFT) was calculated by the B3LYP density functional model with 6-31G(d,p) basis set by Gaussian 09 W program. Spectral characteristics of coumarin102 have been probed into by methods of experimental UV-visible, and quantum chemistry. The UV spectrum was measured in methanol. The optimized structures, total energies, electronic states (HOMO- LUMO), energy gap, ionization potentials, electron affinities, chemical potential, global hardness, softness, global electrophilictity, and dipole moment were measured. We find good agreement between experimental data of UV spectrum and

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Publication Date
Wed Jan 01 2020
Journal Name
Periodicals Of Engineering And Natural Sciences (pen)
Estimating the reliability function of the asymmetrical hybrid parallel-series system: Applied study at the state company for vegetable oils industry
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The research studied and analyzed the hybrid parallel-series systems of asymmetrical components by applying different experiments of simulations used to estimate the reliability function of those systems through the use of the maximum likelihood method as well as the Bayes standard method via both symmetrical and asymmetrical loss functions following Rayleigh distribution and Informative Prior distribution. The simulation experiments included different sizes of samples and default parameters which were then compared with one another depending on Square Error averages. Following that was the application of Bayes standard method by the Entropy Loss function that proved successful throughout the experimental side in finding the reliability fun

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Scopus
Publication Date
Sun Oct 02 2016
Journal Name
Journal Of Educational And Psychological Researches
The Effect of Driver and Posner Models in correcting Alternative Perceptions in Educational Psychology Material for the Students at the Institute of Fine Arts
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To achieve the goals, the researcher followed the design of equal and   independent groups of partial control and post-test . The research has chosen the Institute of Fine Arts in the area Almansour area as deliberate sample where three sections of students have been chosen and the   number of students is (69) students. The researcher conducted equivalence in the variables (age, and IQ , and the overall rate for grade III). in diagnostic phase,  (21) concepts of alternative    image out of (46) concepts have been identified in addition to the goals of formulation of acquisition concepts according to the three processes (definition, discrimination and application). Achievement test has been

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Publication Date
Mon Feb 01 2016
Journal Name
Journal Of Economics And Administrative Sciences
Relation & effect of Human resources management strategic with at work stress : Explorative study
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Abstract

The mine object for this research is determine the nature of the relation and effect between Human resources management strategic to less the  work stress , Human resources management strategic represent a set of procedures and practices to manage the human resources   at the organization. the stress of work effect on the performance of the human resources , al rasheed bank select to applied the qustioneer on the 32 person the work on the sebaa branch , using the qustioneer as a tool to collect data that is design  according some of the standards and make the validity and stability. to analyses this data by using spss for computation " percentage , mean , standard , deriation

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Publication Date
Wed Jun 01 2011
Journal Name
Journal Of Economics And Administrative Sciences
Selection of the initial value of the time series generating the first-order self-regression model in simulation modeAnd their impact on the accuracy of the model
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In this paper, compared eight methods for generating the initial value and the impact of these methods to estimate the parameter of a autoregressive model, as was the use of three of the most popular methods to estimate the model and the most commonly used by researchers MLL method, Barg method  and the least squares method and that using the method of simulation model  first order autoregressive through the design of a number of simulation experiments and the different sizes of the samples.

                  

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