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alkej-204
Experimental Study of the Effect of Exhaust Gas Recirculation (EGR) and Injection Timing on Emitted Emissions at Idle Period
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Abstract

Heavy-duty diesel vehicle idling consumes fossil fuel and reduces atmospheric quality at idle period, but its restriction cannot simply be proscribed. A comprehensive tailpipe emissions database to describe idling impacts is not yet available. This paper presents a substantial data set that incorporates results from DI multi-cylinders Fiat diesel engine. Idle emissions of CO, hydrocarbon (HC), oxides of nitrogen (NOx), smoke opacity, carbon dioxide (CO2) and noise have been reported, when three EGR ratios (10, 20 and 30%) were added to suction manifold.

CO2 concentrations increased with increasing idle time and engine idle speed, but it didn’t show clear effect for IT advancing. CO concentrations increased for all the studied tests with adding EGR. HC concentration increased with idle time advance, but it reduced with increasing idle speed and advancing engine IT. NOx concentrations reduced with adding EGR for all the tested variables. NOx increased with increasing idle time, engine speed and advancing IT. Smoke opacity increased with increasing idle time and retarding IT. Using EGR increased opacity for all tested cases. EGR addition reduced engine noise for all tested cases. Engine noise increased with increasing idle time and retarding IT.

 

 

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Publication Date
Sun Jul 06 2014
Journal Name
Journal Of Educational And Psychological Researches
The influence of Online Training Courses on Iraqi EFL Instructors Teaching and Learning Process
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For over a decade, educational technology has been used sparingly in our schools and universities. Online training courses have been used since 2003 to fill the gaps in our learning system and to add extra program besides classroom learning. This paper aims to investigate the Iraqi EFL instructors’ participating in online training courses and its influence on the process of teaching and learning.

       The sample of present study consists of 30 instructors from University of Baghdad. The questionnaire of sixteen items was constructed. After ensuring validity and reliability of questionnaire, it was applied on March 2013 and the result shows that most of instructors improve their teaching methods b

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Publication Date
Wed Dec 18 2019
Journal Name
Baghdad Science Journal
Effect of Refractive Index on Photon Natural Mass and Wavelength
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In this article it is proved experimentally that the photon is a particle that has mass and constant wavelength by explaining the effect of refractive index on the wavelength and the natural mass of photon. It is very difficult to measure the mass of photon, a simple and easy process was proposed in this paper to calculate the mass length of photon in vacuum (Y) and in medium (Y*), by measuring the length of laser beam in air (Lair) and in medium (Lmed). A new method was postulated to calculate refractive index by using these relations (n = Y*/Y), and (n = Lmed / Lair) which supposed a new theory of light.

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Publication Date
Mon Oct 06 2014
Journal Name
Journal Of Educational And Psychological Researches
The Effect of the Problem Based Learning on EFL Learners’ Achievement
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The present study discusses the problem based learning in Iraqi classroom. This method aims to involve all learners in collaborative activities and it is learner-centered method. To fulfill the aims and verify the hypothesis which reads as follow” It is hypothesized that there is no statistically significant differences between the achievements of Experimental group and control group”. Thirty learners are selected to be the sample of present study.Mann-Whitney Test for two independent samples is used to analysis the results. The analysis shows that experimental group’s members who are taught according to problem based learning gets higher scores than the control group’s members who are taught according to traditional method. This

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Publication Date
Sun Jan 04 2015
Journal Name
Journal Of Educational And Psychological Researches
The Effect of the Problem Based Learning on EFL Learners’ Achievement
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The present study discusses the problem based learning in Iraqi classroom. This method aims to involve all learners in collaborative activities and it is learner-centered method. To fulfill the aims and verify the hypothesis which reads as follow” It is hypothesized that there is no statistically significant differences between the achievements of Experimental group and control group”. Thirty learners are selected to be the sample of present study.Mann-Whitney Test for two independent samples is used to analysis the results. The analysis shows that experimental group’s members who are taught according to problem based learning gets higher scores than the control group’s members who are taught according to traditional method. This

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Publication Date
Sat Apr 01 2023
Journal Name
Egyptian Journal Of Veterinary Sciences
Effect of Crocin on the Spermatogenesis Indices of Mice Testis: A Histopathological and Histomorphological Study
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Publication Date
Mon Feb 01 2021
Journal Name
International Medical Journal
The Effect of Adding Poloxamer Surfactant on Cleaning Efficiency of NaOCl and NaOH (SEM Study)
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Objectives: The purpose of this in vitro study was to compare the effect of adding a poloxamer surfactant to the irrigant solutions on its cleaning efficiency. Design: In this study the roots of extracted permanent premolar teeth were used and evaluated by using Scanning Electronic Microscopy (SEM). Materials and Method: 72 human single tooth of permanent premolar (8 for each group) were used in this in vitro study. Roots after sectioning at cervical area to get 15 mm were embedded in a plastic container filled with impression silicon, then instrumented with ProTaper rotary instruments till size F4. Each group (8 root) were irrigated with one of the nine solutions used in study: three concentrations of NaOH [5% (A1), 2.5%(A2), 0.5%(A3)], th

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Publication Date
Sat Nov 30 2019
Journal Name
Journal Of Engineering And Applied Sciences
Study the Effect of Heat Treatment and Pressure on Some Electrical Properties of Nano Polycarbonate
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In the present research, the electrical properties which included the ac-conductivity (σac), loss tangent of dielectric (tan δ) and real dielectric constant (ε’) are studied for nano polycarbonate in different pressures and frequencies as a function of temperature these properties were studied at selective temperature gradients which are (RT-50-100-150-250)°C. The results of the study showed that the values of dielectric constant and dissipation factor increase with increasing pressure and temperature and decreases by increasing frequency. And the results of electrical conductivity showed that it increases with increasing temperature, pressure and frequency.

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Publication Date
Thu Feb 01 2024
Journal Name
Journal Of Materials Science
Investigations on TiO2–NiO@In2O3 nanocomposite thin films (NCTFs) for gas sensing: synthesis, physical characterization, and detection of NO2 and H2S gas sensors
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Publication Date
Tue Mar 30 2010
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
The Inhibition Effect of Peach Juice on Corrosion of Low Carbon Steel in Hydrochloric Acid at Different Temperatures
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The corrosion inhibition of low carbon steel in1N HCl solution in the presence of peach juice at temperature (30,40,50,and 60)°C at concentration ( 5, 10, 20, 30, 40and 50 cm3/L)were studied using weight loss and polarization techniques. Results show that the inhibition efficiency was increased with the increase of inhibitor concentration and increased with the increase of temperature up to 50ºC ,above 50ºC (i.e. at 60 ºC) the values of efficiency decreases. Activation parameters of the corrosion process such as activation energies, Ea, activation enthalpies, ΔH, and activation entropies, ΔS, were calculated. The adsorption of inhibitor follows Langmuir isotherm. Maximum inhibition efficiency obtained was a bout 91% at 50ºC in the

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Publication Date
Tue Mar 01 2011
Journal Name
Journal Of Economics And Administrative Sciences
Effect of Financial Performance of Jordanian Islamic Banks In the Amman Stock Exchange for the period (1990-2008)
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The last four decades have witnessed a number of rapid and successive international changes in terms of future impacts and orientations. International economy has transformed into a competitive small village due to the information technology revolution and the liberation processes and the economic openness that the market witnesses, there became one market and the activists in this international market are not governments only but rather international organizations and huge multinational corporations where each spares no effort to take every opportunity and face challenges within the frame of  removing all impediments and release transactions under the auspices of  these global developments, the idea of creating Islamic

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