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Laser Peening on Aluminum Alloy 7049 Using Black Paint Surface Coating
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Abstract

Black paint laser peening (bPLP) technique is currently applied for many engineering materials , especially for aluminum alloys due to high improvement in fatigue life and strength . Constant and variable   bending fatigue tests have been performed at RT and stress ratio R= -1 . The results of the present  work observed that the significance of the surface work hardening which generated high negative residual stresses in bPLP specimens .The fatigue life  improvement factor (FLIF)  for bPLP constant fatigue behavior was from 2.543 to 3.3 compared to untreated  fatigue and the increase in fatigue strength at 107 cycle was 21% . The bPLP cumulative fatigue life behavior was improved by 1.786 at L-H and 1.55 at H-L due to black paint coating .

 Keywords: Constant and variable fatigue behavior , Black paint laser peening , 7049 Al- alloy .

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Publication Date
Tue Dec 31 2013
Journal Name
Al-khwarizmi Engineering Journal
Beneficiation of Iraqi Akash at Phosphate Ore Using Organic Acids for the Production of Wet Process Phosphoric Acid
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In the present work, leaching process studiedusing organic acids (acetic acid and lactic acid) to extract phosphate from the Iraqi Akashat phosphate ore by separation of calcareous materials (mainly calcite). This approach characterized by energy conservation, environmental enhancement by recovery of calcite as calcium sulfate (gypsum), keeping the physical and chemical properties of apatite. Samples were analyzed using X-ray diffraction and FTIR spectrophotometer. From the obtained experimental data it was found that using the two organic acids yields closed purity values of the produced apatite at the optimum conditions, while at different acid concentrations, it was found that the efficiency of acetic acid is higher at the low acid co

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Publication Date
Thu Feb 26 2026
Journal Name
Journal Of Baghdad College Of Dentistry
Retentive forces, tensile strength and deflection fatigue of Acetal thermoplastic clasp material in comparison with cobalt-chromium alloy
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Background: Nowadays there is an increasing of the emphasis on aesthetic, dentist have been concerned about providing aesthetics and functional removable partial dentures to their patients and this was make the mission more difficult because of the goal now is achieving optimal aesthetic of the denture - while maintaining retentive, stable, and conservative to the health of supporting tooth and supporting tissue. The traditional use of metal clasp like cobalt-chromium, gold, stainless-steel and titanium hampers esthetics because of its obvious display conflicts with patient’s prosthetic confidentiality. Acetal resin (poly oxy methylene) may be used as alternative denture clasp material. This material was promoted primarily on the basis of

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Publication Date
Wed Sep 20 2023
Journal Name
Chalcogenide Letters
Calculation of the localized and extended energy states density for Ge60Se40-xTex alloy prepared by melting point method
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The DC electrical conductivity properties of Ge60Se40-xTex alloy with x = 0, 5, 10, 15 and 20). The samples were formed in the form of discs with the thickness of 0.25–0.30 cm and the diameter of 1.5 cm. Samples were pressed under a pressure of 6 tons per cm2 , using a ton hydraulic press. They were prepared after being pressed using a ton hydraulic press using a hydraulic press. Melting point technology use to preper the samples. Continuous electrical conductivity properties were recorded from room temperature to 475 K. Experimental data indicates that glass containing 15% Te has the highest electrical conductivity allowing maximum current through the sample compared to Lu with other samples. Therefore, it is found that the DC co

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Publication Date
Sun May 03 2015
Journal Name
Lasers In Medical Science
Investigations of radicular dentin permeability and ultrastructural changes after irradiation with Er,Cr:YSGG laser and dual wavelength (2780 and 940 nm) laser
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Publication Date
Sun Sep 04 2016
Journal Name
Baghdad Science Journal
Surface-Subface Geochemical and Mineralogical Study of Gypcrete in Alexandria Area Central Iraq
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Gypsiferous soil deposits (Gypcrete) are weakly consolidate earthy mixture of secondary gypsum, sand and clay. It is formed in arid and semi- arid area with annual precipitation rainfall less than 400mm. These sediments occur in surface and subsurface in region of little rainfall and rapid evaporation. This research deals with the study of gypcrete in Alexandria to improve the mineralogical and geochemical properties of the gypcrete. The gypcrete soil is used as raw material to produce the plaster for building purposes. Three samples of gypcrete were chemically and geochemically analyzed. The common mineral is howed in 0-0.5m Gypsum followed by Calcite in 0-1m and Quartz in 1-1.5m due to leaching and infiltration by rainfall as well as it

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Publication Date
Thu Oct 12 2017
Journal Name
Iraqi Journal Of Laser
A Comparative Evaluation of Post-Operative Pain and Function after Gingival Depigmentation Using 940 Nm Diode Laser And Conventional Bur Method: 6 Months Study
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The aim of the study was to evaluate the efficacy of diode laser (λ=940 nm) in the management of gingival hyperpigmentation compared to the conventional bur method. Materials and methods: Eighteen patients with gingival hyperpigmentation were selected for the study with an age between 12-37 years old. The site of treatment was the upper gingiva using diode laser for the right half and the conventional method for the left half. All patients were re-evaluated after the following intervals: 3 days, 7 days, 1 month and 6 months post-operation. Pain and functions were re-evaluated in each visit for a period of 1 day, 3 days and 1 week post-operation. Laser parameters included 1.5 W in continuous mode with an initiated tip (400 μm) placed in

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Publication Date
Sun Dec 01 2019
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Measuring the impact of internal control on tax performance using balanced score card indicators: An applied research in a sample of the branches of the General Tax Authority in Iraq
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This research dealt with the impact of internal control on tax performance using balanced scorecard indicators because of its special importance in improving tax performance and reform. The internal control system is a safety valve for senior management in all organizations, it plays an important role in the regularity and development of work and the fight against corruption To provide reliable and accurate data and information, follow up on compliance with laws, regulations and instructions. The aim of this research is to demonstrate how control affects tax performance and how to adapt internal control components to improve tax performance. In the General Authority for taxes and its branches,. The research resulted in a number of conclu

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Publication Date
Mon Feb 18 2019
Journal Name
Iraqi Journal Of Physics
Preparation and characterization of colloidal CdTe nanoparticles by laser ablation in liquids
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Nanoparticles generation by laser ablation of a solid target in a liquid environment is an easy method. Cadmium Telluride (CdTe) colloidal nanoparticles have been synthesized by laser ablation Nd:YAG with wavelengths of 1064nm and double frequency at 532 nm, number of pulses 50 pulses, with pulse energy= 620mJ, 700mJ of a solid target CdTe is immersed in double distilled deionized water (DDIW) and in methanol liquid. Influences of the laser energy and different solutions on the formation and optical characterization of the CdTe nanoparticles have been studied using atomic force microscope (AFM) and the UV-Vis absorption. As a results, it leads to the absorbance in UV-Vis spectra of samples prepared in water at laser wavelength of 532nm i

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Publication Date
Mon Dec 20 2021
Journal Name
Baghdad Science Journal
Recurrent Stroke Prediction using Machine Learning Algorithms with Clinical Public Datasets: An Empirical Performance Evaluation
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Recurrent strokes can be devastating, often resulting in severe disability or death. However, nearly 90% of the causes of recurrent stroke are modifiable, which means recurrent strokes can be averted by controlling risk factors, which are mainly behavioral and metabolic in nature. Thus, it shows that from the previous works that recurrent stroke prediction model could help in minimizing the possibility of getting recurrent stroke. Previous works have shown promising results in predicting first-time stroke cases with machine learning approaches. However, there are limited works on recurrent stroke prediction using machine learning methods. Hence, this work is proposed to perform an empirical analysis and to investigate machine learning al

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Scopus (13)
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Publication Date
Fri Mar 01 2019
Journal Name
Al-khwarizmi Engineering Journal
Peak to Average Power Ratio Reduction of OFDM Signals Using Clipping and Iterative Processing Methods
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One of the serious problems in any wireless communication system using multi carrier modulation technique like Orthogonal Frequency Division Multiplexing (OFDM) is its Peak to Average Power Ratio (PAPR).It limits the transmission power due to the limitation of dynamic range of Analog to Digital Converter and Digital to Analog Converter (ADC/DAC) and power amplifiers at the transmitter, which in turn sets the limit over maximum achievable rate.

        This issue is especially important for mobile terminals to sustain longer battery life time. Therefore reducing PAPR can be regarded as an important issue to realize efficient and affordable mobile communication services.

   

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