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joe-2020
Experimental and Theoretical Investigation of Noise Effect in Centrifugal Fan Impeller
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In this work a study was made in centrifugal fan blower to investigate the effect of impeller blade design on sound pressure level (SPL). Shroud and unshroud impeller of nine blades are used. The sound generation from flow inside the test rig at different positions was displayed by using spectral analyzer. The experiments were carried out in anechoic chamber with small holes in its walls, under ambient condition about (25-27) C ° to avoid the effect of temperature on the sound pressure level. The results showed that (SPL) decreased with the increase of distance from the source about (3-4)dB when distance varied about (0.8-1.06)m, and the (SPL) decreased with the decrease of velocity about (8-12)dB when velocity varied between (13000-2600) r.p.m., and when the velocity remain constant (SPL) increased with the increased of pressure about (7-15)dB when the pressure varied between (36-8)mbar. For the purpose of comparison, two types of impellers were tested under same conditions, the results showed that (SPL) increased when shroud used on the impeller. The mathematical results show good agreement with the experimental results. The study also concluded a spectral analysis of the noise generated using 1/3 octave band filter. The analysis showed that (SPL) increased with frequency range of (0.8-400) Hz. The maximum sound pressure level was appeared clearly in the frequency range between 200 – 400 Hz .

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Publication Date
Sun Mar 01 2020
Journal Name
Iraqi Journal Of Physics
Study the performance of pentacene based organic field effect transistor by using monolayer, bilayer and trilayer with different gate insulators
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In this paper, Pentacene based-organic field effect transistors (OFETs) by using different layers (monolayer, bilayer and trilayer) for three different gate insulators (ZrO2, PVA and CYEPL) were studied its current–voltage (I-V) characteristics by using the gradual-channel approximation model. The device exhibits a typical output curve of a field-effect transistor (FET). Source-drain voltage (Vds) was also investigated to study the effects of gate dielectric on electrical performance for OFET. The effect of capacitance semiconductor in performance OFETs was considered. The values of current and transconductance which calculated using MATLAB simulation. It exhibited a value of current increase with increasing source-drain voltage.

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Publication Date
Wed Jan 18 2017
Journal Name
Effect Of Cutting Angle And Knives Type On Some Operational Characteristics For A Locally Manufactured Palm Pruning Motorized Vibration Cutter‏ Aa Jasim, Mr Abbood, Sm Abbood‏
Effect of Cutting Angle and Knives Type on Some Operational Characteristics for a Locally Manufactured Palm Pruning Motorized Vibration Cutter‏
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Publication Date
Thu Jan 16 2020
Journal Name
Indian Journal Of Forensic Medicine & Toxicology
Effect of Addition of Composite Polyamide Micro Particles and Silicone Dioxide NanoParticle on Some Mechanical Properties of Room Temperature Vulcanized Maxillofacial Silicone Elastomer Before and after Artificial Aging
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Background: The most common reason for re-making a maxillofacial prosthesis is the degradation of the mechanical properties of the silicone. Aim of this study: To assess some mechanical properties of VST-50F maxillofacial silicone reinforced with a composite of silicon dioxide nanoparticle and polyamide-6 microparticle before and after artificial aging. Material and Method: Preparing 240 samples tested for tear strength, tensile strength and elongation percentage, hardness, and roughness before and after aging. The Silicon dioxide was added in concentrations of 1% by weight and Polyamide-6 in the concentration of 0.25% and 0.5% by weight to the VST-50F RTV maxillofacial silicone. The one-way ANOVA and post hoc tests were used for inferentia

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Publication Date
Sun Sep 01 2013
Journal Name
Baghdad Science Journal
Effect of Polyherbs-Mixture Composed of Nigella sativa, Trigonella foenum - graceum, Cyperus rotundus and Teucrium polium on the Levels of Malondialdehyde and Glutathione for Diabetic Patients Type II
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This study included estimation of glutathione (GSH) and Malondialdehyde (MDA) levels in the serum of diabetic patients type II who are treated with a polyherbs mixture (Nigella sativa, Trigonella foenum-graeum, Cyperus rotundus and Teucrium polium) for three months of treatments. Seventy samples of diabetic patients Type II male and females with age about (35-60) years were taken including 44 samples for group one (24 male, 20 female) who used herbs accompanied with chemical treatment (drugs) and 26 samples for the second group (13male and 13 female) who used herbs only. These groups were compared with 60 samples obtained from healthy persons (29 male, 31 female) at the same age of patients as a control group. Effect of age and treatment fo

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Publication Date
Wed Dec 04 2024
Journal Name
المورد
((The effect of mentioning, deleting, or changing the form of some Arabic letters on the meaning of the context of the sentence in Arabic))
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The letters are exposed in some texts of the classical Arabic language (poetry or prose), or in some of the Qur’anic texts, which are the main sources that were adopted on the day when provisions, rules and linguistic controls were established. I say that some of these letters are exposed in some contexts to deletion, mention, or change in the structure and shape of the letter. As for the omission, it is one of the aspects that distinguished Arabic, as well as other languages, for many purposes that differ among their user.

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Publication Date
Wed Jan 21 2026
Journal Name
Journal Of Physical Education
The effect of special exercises using a designer device and added relative weights to develop some of the physical abilities of volleyball players
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Publication Date
Tue Jan 01 2013
Journal Name
العلوم التربوية والنفسية
The effect of a strategy for creative thinking on the achievement of chemistry and the reading comprehension ability of secondary school female students
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Publication Date
Wed Dec 14 2016
Journal Name
Journal Of Baghdad College Of Dentistry
Evaluation the Effect of Addition of Plasma Treated Polypropylene Fiber and Silanized Silicon Dioxide Nanoparticles Composite on Some Properties of Heat-Polymerized Polymethylmethacrylate
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Background: Polymethylmethacrylate (PMMA) is the most ‎commonly used m‏aterial in denture construction. This material is ‎far from ideal in fulfilling the‎ mechanical requirements, like low impact and transverse strength and poor thermal conductivity are present in this material. The purpose of this study was to study the effect of addition a composite which include 1%wt silanized silicone dioxide nano fillers (SiO2) and 1wt% oxygen plasma treated polypropylene fiber (PP) on some properties of heat cured acrylic resin denture base material (PMMA). Materials and methods: One hund‏red (100) prepared specimens were divided into five groups according to the tests, each group consisted of 20 specimens and t

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Publication Date
Wed Jan 01 2020
Journal Name
Annals Of Tropical Medicine And Public Health
EFFECT OF EUCALYPTUS AND MYRTUS EXTRACTS IDENTIFICATION BY GAS CHROMATOGRAPHY-MASS SPECTROMETRY ON SOME SPECIES OF CANDIDA AS A MODEL OF MEDICAL PLANTS
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Publication Date
Sun Oct 15 2023
Journal Name
Bionatura
Study of the Effect of Diabetes Mellitus I on Bone Mineral Density of Upper and Lower Limbs by Dual-Energy X-Ray Absorptiometry
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Background: Bone mineral density (BMD) has been assessed using Dual-Energy X-ray absorptiometry (DEXA). This procedure is considered to be of vital importance in assessing the general condition of individuals concerning their skeletal mineralization. BMD is measured according to the results of the DEXA examination of the vertebral column and pelvis. Although diabetes mellitus (D.M.)is known to affect BMD, the information regarding this relationship is not currently particularly clear. Objective: This study concentrates on the point that the assessment of BMD for the vertebral column is insuffi-cient to give a realistic and correct picture of the mineralization of the remaining part of the skeleton. Besides, this study elicited a gen

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