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An experimental and numerical investigation of heat transfer effect on cyclic fatigue of gas turbine blade
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Blades of gas turbine are usually suffered from high thermal cyclic load which leads to crack initiated and then crack growth and finally failure. The high thermal cyclic load is usually coming from high temperature, high pressure, start-up, shut-down and load change. An experimental and numerical analysis was carried out on the real blade and model of blade to simulate the real condition in gas turbine. The pressure, temperature distribution, stress intensity factor and the thermal stress in model of blade have been investigated numerically using ANSYS V.17 software. The experimental works were carried out using a particular designed and manufactured rig to simulate the real condition that blade suffers from. A new controlled method in this rig was suggested to heating the specimen depending on Oxygen-gas flame. The numerical result shows that the temperature distribution over the blade varying with the load change, which leads to increase the stress intensity factor along the crack. The experimental result indicates that the rate of crack propagation varying with the position of crack and with the angle of inclined. Based on this result, more effective cracks on the blade were satisfied which are highly effect the blade lifetime.

 

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Publication Date
Sun Dec 10 2017
Journal Name
Al-academy
cognitive references of the directorial imagination and modeling of the theatrical actor performance
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This research is determined by the study of  the " cognitive references of the directorial imagination and modeling of  the theatrical actor performance ." it has described an Iraqi theatrical model, The research began with the great importance of the director's imagination as the basic premise for crystallizing the  director's vision according to its cognitive references in creating a solid performance model based on the aesthetic, intellectual and technical bases, It is also contributes to the formation of the theatrical show as a technical framework that presents the show in one unified fabric.

The research sought to reach through the problem of research, which is in the question of: What is the modeling of the

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Publication Date
Wed Jun 03 2020
Journal Name
Political Sciences Journal
The world'srefugeesbetween the aggravation of the situation and the endeavors of international organizations
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Human witnessed over the centuries many of the important issues faced by the international community was centered on human rights in general and the persecution of refugees, especially according to many forms may be directly or indirectly leaves behind economic crises, social and humanitarian push world countries to rethink the mechanisms and the feasibility of developing agreements and laws and the role of international and regional organizations to protect peoplerefugeestatus.

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Publication Date
Tue May 16 2023
Journal Name
Journal Of Engineering
Application of Wavelet Packet and S Transforms for Differential Protection of Power Transformer
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The differential protection of power transformers appears to be more difficult than any type of protection for any other part or element in a power system. Such difficulties arise from the existence of the magnetizing inrush phenomenon. Therefore, it is necessary to recognize between inrush current and the current arise from internal faults. In this paper, two approaches based on wavelet packet transform (WPT) and S-transform (ST) are applied to recognize different types of currents following in the transformer. In WPT approach, the selection of optimal mother wavelet and the optimal number of resolution is carried out using minimum description length (MDL) criteria before taking the decision for the extraction features from the WPT tree

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Publication Date
Wed Feb 20 2019
Journal Name
Iraqi Journal Of Physics
Preparation of polyaniline polymer and using it as a Vapor sensor of acids
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 Polyaniline organic Semiconductor polymer was prepared by oxidation polymerization by adding hydrochloric acid concentration of 0.1M and potassium per sulfate concentration of 0.2M to 0.1M of aniline at room temperature, the polymer was deposited at glass substrate, the structural and optical properties were studies through UV-VIS, IR, XRD measurements, films have been operated as a sensor of vapor  H2SO4 and HCl  acids.

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Crossref
Publication Date
Tue Nov 01 2016
Journal Name
Journal Of Engineering
Modeling of Comparative Performance of Asphalt Concrete under Hammer, Gyratory, and Roller Compaction
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The main objective of this study is to develop predictive models using SPSS software (version 18) for Marshall Test results of asphalt mixtures compacted by Hammer, Gyratory, and Roller compaction. Bulk density of (2.351) gm/cc, at OAC of (4.7) % was obtained as a benchmark after using Marshall Compactor as laboratory compactive effort with 75-blows. Same density was achieved by Roller and Gyratory Compactors using its mix designed methods.

A total of (75) specimens, for Marshall, Gyratory, and Roller Compactors have been prepared, based on OAC of (4.7) % with an additional asphalt contents of more and less than (0.5) % from the optimum value. All specimens have been subjected to Marshall Test. Mathematical model

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Publication Date
Sun Jan 01 2023
Journal Name
International Journal Of Economics And Finance Studies
THE ROLE OF EXTERNAL INDEBTEDNESS OF THE ECONOMIC AND FINANCIAL DEVELOPMENT IN IRAQ
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The imperative of achieving financial stability has transcended national boundaries, necessitating heightened attention from both researchers and policymakers. Consequently, this article delves into an examination of the impact of government debt and public debt on financial development within the context of Iraq. The study employs monetary policy, interest rate, inflation, and population growth as control variables to prognosticate financial development. Utilizing data extracted from the World Development Indicators (WDI) spanning the period from 1995 to 2022, the study employs the dynamic autoregressive distributed lag (DARDL) approach to scrutinize the associations under investigation. The findings underscore a negative association betwe

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Scopus
Publication Date
Wed May 01 2019
Journal Name
Solid State Phenomena
Preparation and Study of the Mechanical Properties of Unsaturated Polyester Resin/Graphene Nanocomposite
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Nanocomposite was prepared using unsaturated polyester (UP) resin as a matrix and graphene nanoparticles as a reinforcement material in six percentage weights (0, 0.1, 0.2, 0.3, 1 and 1.5%). Mechanical, calorimetric and thermal studies were performed on the (UP) resin/graphene nanocomposite. All tests showed a clear improvement of all mechanical properties examined (hardness, flexural strength (F.S), impact strength (I.S) and tensile strength (T.S)) with increasing graphene percentage. In addition, the temperature of glass transition and thermal conductivity of this composite increased with increasing graphene content.

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Publication Date
Sun Mar 05 2017
Journal Name
Baghdad Science Journal
Synthesis and Modification of Some New Transition Metal Complexes of Poly (vinyl chloride)
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Theligand4-[5-(2-hydoxy-phenyl)- [1,3,4- thiadiazole-2- ylimino methyl]-1,5-dimethyl -2-phenyl-1,2-dihydro-pyrazol-3-one [HL1] is prepared and characterized. It is reacted with poly(vinyl chloride) (PVC) in THF to form the PVC-L compounds ,PVC-L interacted with ions of transition metals to form PVC-L-MII complexes .All prepared compounds are characterized by FTIR spectroscopy, u.v-visible spectroscopy, C.H.N.S. analysis and some of them by 1HNMR

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Publication Date
Sun Mar 07 2010
Journal Name
Baghdad Science Journal
Identification and Purification of Cholera Like Toxin from Environmental Isolate of Vibrio cholerae
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The presence and prevalence of V. cholerae were investigated in forty five water samples collected from different locations of Tiger River/ Baghdad city. Twenty one isolates were isolated by adopting a simple isolation techniques. The final identification revealed that only three isolates were confirmed as V. cholerae. They were named 1J, 1R and Dial 131 which are all serogrouped as non-O1. Toxin Coregulated Pili (TCP) and heat labile enterotoxin (LT) were determined in only the environmental isolate 1J while non of the isolates produced heat stabile toxin (ST). The purification scheme was improved, few steps were adopted to include back extraction of ammonium sulfate, saturation between 80-20%, desalting through Sephadex G25, and gel filt

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Crossref
Publication Date
Sat Oct 01 2016
Journal Name
Journal Of The College Of Basic Education
Some Thermodynmic Properties of binary Mixtures of Alcohol isomers and Sulfolane at 298.15K
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The refractive indices, nD densities 𝜌, and viscosities  of binary mixtures of sulfolane + n -butanol + sec- butanol + iso- butanol + tert – butanol + n-propanol and iso- propanol were measured at 298.15K. Form experimental data, excess molar volum VE , excess molar refractivity ∆nD, excess molar viscosity  E and excess molar Gibbs free energy of activation of viscous flow G *E were calculated. From n-propanol – sulfolane and iso- propanol sulfolane mixtures showed negative ∆nD, n-butanol – sulfolane, sec-butanal – sulfolane, iso-butanol – sulfolane and tert- butanol sulfolane , nD was positive over the whole mole fraction rang , while VE ,  E and G *E show a negative deviation. The

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