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Experimental Determination of the Elastic and Viscous Behavior of Polycarbonate Melts at Different Temperatures and Their Relationship to the Steady State Viscosity via the Cox-Merz Rule
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Rheological instrument is one of the basic analytical measurements for diagnosing the properties of polymers fluids to be used in any industry. In this research polycarbonate was chosen because of its importance in many areas and possesses several distinct properties.
Two kinds of rheometers devices were used at different range of temperatures from 220 ˚C-300 ˚C to characterize the rheological technique of melted polycarbonate (Makrolon 2805) by a combination of different investigating techniques. We compared the results of the linear (oscillatory) method with the non-linear (steady-state) method; the former method provided the storage and the loss modulus of melted polycarbonate, and presented the Cox-Merz model as well. One of the major problems in measuring the viscosity of polycarbonate at high shear rates, especially at the extremes of temperatures, was that during the use of the capillary rheometer, long molecule chains led to high viscosity.

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Publication Date
Mon Apr 04 2022
Journal Name
Journal Of Educational And Psychological Researches
Some Indicators of Learning Difficulties and their Relationship to the Self-Concept of Elementary School Students (Case Study)
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The aim of the research is to identify learning difficulties and their role in children's perception of self-concept. The researcher adopted the descriptive and analytical approach method in this study. A questionnaire was designed by the researcher to collect some related information such as biodata, family, health, diagnostic and behavioral patterns of the case. In addition, the researcher adopted the scale of learning difficulties for elementary school students prepared by Zaidan Ahmed Al-Sartawi (1995), the scale of student appreciation for the survey of learning difficulties for primary school students by Michael Best, which was translated to the Arabic language by (Saeed Abdullah Debis). The researcher adopted also the Self-Concept

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Publication Date
Wed Jan 31 2024
Journal Name
Iraqi Geological Journal
Estimation of Rock Mechanical Properties of the Hartha Formation and their Relationship to Porosity Using Well-Log Data
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The physical and elastic characteristics of rocks determine rock strengths in general. Rock strength is frequently assessed using porosity well logs such as neutron and sonic logs. The essential criteria for estimating rock mechanic parameters in petroleum engineering research are uniaxial compressive strength and elastic modulus. Indirect estimation using well-log data is necessary to measure these variables. This study attempts to create a single regression model that can accurately forecast rock mechanic characteristics for the Harth Carbonate Formation in the Fauqi oil field. According to the findings of this study, petrophysical parameters are reliable indexes for determining rock mechanical properties having good performance p

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Publication Date
Fri Aug 31 2012
Journal Name
Al-khwarizmi Engineering Journal
Types of the Fiber Glass-Mat on Fatigue Characteristic of Composite Materials at Constant Fiber Volume Fraction: Experimental Determination
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The aim of this work is to study the influence of the type of fiber glass –mat on fatigue behavior of composite material which is manufactured from polyester and E-glass (woven roving, chopped strand mat (CSM)) as a laminate with a constant fiber volume fraction (VF) of 33%. The results showed that the laminates reinforced with E-glass (woven roving) [0/90, ±45.0/90] and [0/90, CSM, 0/90] have lower fatigue strength than the laminates reinforced with E-glass [0/90]3,[CSM]3 and [CSM, 0/90, CSM]  although they had different tensile strength; the best laminate was [0/90]3 .

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Publication Date
Tue Feb 12 2019
Journal Name
Iraqi Journal Of Physics
A study of the structural and electrical properties of Ni1-x Cox Fe2O4 ferrites
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Ferrite with general formula Ni1-x Cox Fe2O4(where x=0.0.1,0.3,0.5,0.7, and 0.9), were prepared by standard ceramic technique. The main cubic spinel structure phase for all samples was confirmed by x-ray diffraction patterns. The lattice parameter results were (8.256-8.299 °A). Generally, x -ray density increased with the addition of Cobalt and showed value between (5.452-5.538gm/cm3). Atomic Force Microscopy (AFM) showed that the average grain size and surface roughness was decreasing with the increasing cobalt concentration. Scanning Electron Microscopy images show that grains had an irregular distribution and irregular shape. The A.C conductivity was found to increase with the frequency and the addition of Cobal

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Publication Date
Thu Nov 01 2018
Journal Name
Journal Of Economics And Administrative Sciences
The Reflection of self competency of the managers in their behavior
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Abstract

      This research aims to measure the effect of Self competency of the Managers in their behavior from the view point of the working individual in the organization since the behavior of managers is considered to be one of the essential variables in the organization which can affect the performance and the commitment of the working individual. the questioners was used to gather the data and the Iraqi Rail Road co. was the field of the study . and a random sample of (36) individual of the subordinates of the managers society of the study and used the (SPSS) statistical program was used in the analysis of the data of the research . the findings refer to the existence of a

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Publication Date
Fri Oct 01 2010
Journal Name
Iraqi Journal Of Physics
The effect of TiO2 addition on the thermal conductivity of Polymethylmetha acrylate, Polycarbonate and Polystyrene Polymers
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Thermal conductivity measurement was done for specimens of Polystyrene/ titanium dioxide, Polycarbonate/ titanium dioxide and Polymethylmetha acrylate/ titanium dioxide composites for weight ratio of 1.9/ 0.1 and 1.8/ 0.2 wt% for different thickness of the samples. The experimental results show that the thermal conductivity is increased with the increasing of thickness of layers and with the weight ratio of TiO2

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Publication Date
Sun Mar 26 2017
Journal Name
Iraqi Journal Of Pharmaceutical Sciences ( P-issn 1683 - 3597 E-issn 2521 - 3512)
The Spectrophotometric Determination of Olanzapine via Coupling with Diazotized p-Nitroaniline
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A new spectrophotometric method has been developed for the assay of olanzapine (OLN.) in pure and dosage forms. The method is based on the diazocoupling of (OLN.) with diazotized p-nitroaniline in alkaline medium to form a stable brown colored water-soluble azo dye with a maximum absorption at 405 nm.  The variables that affect the completion of reaction have been carefully optimized. Beer’s law is obeyed over the concentration range of (0.5-45.0 μg.mL-1) with a molar absorptivity of 1.5777×104 L.mol-1.cm-1.  The limit of detection was  0.3148  Î¼g.mL-1 and  Sandell’s  sensitivity value was 0.0198 μg.cm-2. The propose

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Publication Date
Sun May 01 2022
Journal Name
International Journal Of Early Childhood Special Education (int-jecs)
Study of some visual functions and functional variables of the respiratory and nervous systems and their relationship to the level of achievement of air rifle shooting
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The purpose of this paper is to identifying the relationship between some visual functions and the level of achievement of air rifle shooting among young Iraqi female, and identifying the relationship between some functional variables of the respiratory and nervous systems at the level of achievement of air rifle shooting among young Iraqi female. The researchers used the descriptive approach in the correlative relationships style for its suitability and the research problem. The researchers determined the research community by the intentional method represented by (10) young female shooters who represent the national team with air rifle shooting effectiveness, and who represent (100%) of the research community. One of the most important re

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Publication Date
Mon Jan 01 2018
Journal Name
Al–bahith Al–a'alami
The Interactive Relationship between the Formation Elements and their Implications in the Structure of the Television Image
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The image of television dominates the cognitive and artistic motivations. It is the formulation of ideas and visions along with its documentary ability. It is the main element in television work as it is a story that is narrated in pictures. Therefore, attention to image building is a major point of gravity in the work structure as a whole. On the image is the element carrying all aesthetic and expressive values of news and information directly to the hints that work to stimulate and stir the imagination of the recipient to evoke mental images added to the visual images to deepen the meanings.
All visual arts carry elements and components that follow in a particular pattern to give special meanings and specific connotations. However,

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Publication Date
Wed Jun 07 2023
Journal Name
Journal Of Educational And Psychological Researches
The Difficulties Facing the Schools of Challenge and Resilience and their Relationship to Motivation towards School Work for Its Workers in Hebron Governorate
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The current study aims to examine the level of problems faced by university students in distance learning, in addition to identify the differences in these problems in terms of the availability of internet services, gender, college, GPA, interactions, academic cohort, and family economic status. The study sample consisted of (3172) students (57.3% females). The researchers developed a questionnaire with (32) items to measure distance learning problems in four areas: Psychological (9 items), academic (10 items), technological (7 items), and study environment (6 items). The responses are scored on a (5) point Likert Scale ranging from 1 (strongly disagree) to 5 (strongly agree). Means, standard deviations, and Multivariate Analysis of Vari

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