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Parametric study of thermal behavior of thrust chamber cooling channels
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A numerical investigation is adopted for two dimensional thermal analysis of rocket thrust chamber wall (RL10), employing finite difference model with iterative scheme (implemented under relaxation factor of 0.9 for convergence) to compute temperature distribution within thrust chamber  wall (which is composed of Nickel and Copper layers). The analysis is conducted for different boundary conditions: only convection boundary conditions then combined radiation, convection boundary conditions also for  different aspect ratio (AR) of cooling channel. The results show that Utilizing cooling channels of high aspect ratio leads to decrease in temperature variation across thrust chamber wall, while no effects on heat transferred to the coolant is indicated. The radiation has a considerable effect on the  computed wall temperature values.

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Publication Date
Wed Dec 30 2009
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Monitoring of Evaporated Cooling Tower
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Thep resent study was conducted for monitoring of the evaporative cooling tower in methanol production plant using digital computer' visuql Basic computer program was used for the monitoring of the performance of the cooling tower. The structure program consists of sub programs and forms to show all the related variabltes such as temperature, flow rate, pressure ...etc, that affect the cooling tower operation and give alarms and important function informition regarding these variables.

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Publication Date
Fri Mar 01 2024
Journal Name
Baghdad Science Journal
Study the Structural Properties of Porous Silicon and their Applications as Thermal Sensors
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The photo-electrochemical etching (PECE) method has been utilized to create pSi samples on n-type silicon wafers (Si). Using the etching time 12 and 22 min while maintaining the other parameters 10 mA/cm2 current density and HF acid at 75% concentration.. The capacitance and resistance variation were studied as the temperature increased and decreased for prepared samples at frequencies 10 and 20 kHz. Using scanning electron microscopy (SEM), the bore width, depth, and porosity % were validated. The formation of porous silicon was confirmed by x-ray diffraction (XRD) patterns, the crystal size was decreased, and photoluminescence (PL) spectra revealed that the emission peaks were centered at 2q of 28.5619° and 28.7644° for et

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Publication Date
Sun Dec 02 2018
Journal Name
Journal Of The College Of Education For Women
The Role of Local Satellite Channels in the formation of knowledge and trends of the Iraqi Public Towards Terrorism: A Field Study
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Terrorism is a global phenomenon that engulfs most regions of the world to varying degrees. Media outlets are aware of the many incidents of violence and terrorism that have increased in recent times. The differences between the size of the phenomenon in different societies are the causes and severity of the phenomenon. On the role of local satellite channels in shaping the knowledge and trends of the Iraqi public towards the events of terrorism, in light of the assumptions of reliance on the media. The importance of this study is that it assesses the role of local satellite channels in the formation of knowledge and trends The study seeks to know the extent of exposure of the Iraqi public to local satellite channels, and to reveal the e

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Publication Date
Wed Jun 30 2021
Journal Name
Iraqi Journal Of Market Research And Consumer Protection
THE ROLE OF SATELLITE CHANNELS IN FORMING TRAFFIC AWARENESS AND PREVENTING ACCIDENTS - A FIELD STUDY: THE ROLE OF SATELLITE CHANNELS IN FORMING TRAFFIC AWARENESS AND PREVENTING ACCIDENTS - A FIELD STUDY
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The importance of the research comes from dealing with the problem of lack of traffic awareness, which causes accidents and the occurrence of human and material losses, and the research aims to study the role of satellite channels in forming traffic awareness among the public, and a sample was chosen from Baghdad consisting of (280) individuals, male and female, and used the questionnaire tool. To obtain the data, which included several questions, the results were analyzed statistically and several results were reached, the most important of which is that there is an interest among the public in following traffic programs at a rate of one to two hours to receive information through traffic programs and to identify and apply gener

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Publication Date
Sun Feb 24 2019
Journal Name
Iraqi Journal Of Physics
Construction and performance study of a solar - powered hybrid cooling system in Iraq
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The systems cooling hybrid solar uses solar collector to convert solar energy into the source of heat for roasting Refrigerant outside of the compressor and this process helps in the transformation of Refrigerant from the gas to a liquid state in two-thirds the top of the condenser instead of two-thirds the bottom of the condenser as in Conventional cooling systems and this in turn reduces the energy necessary to lead the process of cooling. The system cooling hybrid use with a capacity of 1 ton and Refrigerant type R22 and the value of current drawn by the system limits (3.9-4.2A), the same value of electric current calculated by the system are  Conventional  within this atmosphere of Iraq, and after taking different readings

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Publication Date
Thu Aug 01 2013
Journal Name
Micron
Computational investigation of electron path inside SEM chamber in mirror effect phenomenon
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Publication Date
Thu Jan 01 2015
Journal Name
Journal Of Engineering
Experimental Study of the effect of closed cavity wall on buildings cooling loads saving
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The experimental study showed the use of closed cavity wall (the thickness of the cavity 5cm) made a percentage reduction in the cooling load caused by heat gain from the wall by (21.5 %) compared with the conventional wall. also the thermal resistance of the closed cavity was an average (0.2 m2.oC/W).

The experimental results of the study showed that the use of closed cavity wall reduced the average temperature of the inner surface of the wall during the day, and that the reduction was an average (0.45 oC)  when compared with the conventional wall , as well as the use of closed cavity wall reduced the temperature difference range of the inner surface of the wall during the day, and that the

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Publication Date
Sun Sep 01 2019
Journal Name
Baghdad Science Journal
Studies on Surface Morphology and Electrical Conductivity of PS Thin Films in Presence of Divalent Complexes
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       Optical properties and surface morphology of pure and doped Polystyrene films with different divalent metals of Zn, Cu and Sn and one concentration percentage have been studied. Measurements of UV-Vis spectrophotometer and AFM spectroscopy were determined. The absorbance, transmittance and reflectance spectrums were used to study different optical parameters such as absorption coefficient, refractive index, extinction coefficient and energy gap in the wavelengths rang 200-800nm. These parameters have increased in the presence of the metals. The change in the calculated values of energy gaps with doping metals content has been investigated in terms of PS matrix structural modification. The value of opt

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Scopus (11)
Crossref (8)
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Publication Date
Wed Oct 17 2018
Journal Name
Journal Of Economics And Administrative Sciences
Comparison of Two of (Turnbull) and (Generalization Turnbulls)non-parametric methods in estimating conditional survival function (applied study on breast cancer patients)
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   This research includes the application of non-parametric methods in estimating the conditional survival function represented in a method (Turnbull) and (Generalization Turnbull's) using data for Interval censored of breast cancer and two types of treatment, Chemotherapy and radiation therapy and age is continuous variable, The algorithm of estimators was applied through using (MATLAB) and then the use average Mean Square Error (MSE) as amusement  to the estimates and the results showed (generalization of Turnbull's) In estimating the conditional survival function and for both treatments ,The estimated survival of the patients does not show very large differences

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Publication Date
Fri Feb 08 2019
Journal Name
Journal Of The College Of Education For Women
الاختیار الامثل لالوان غرفة الطفل وفق بعض المتغیرات
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Color is perhaps the most important element in art because it is what first attracts
attention when looking at any thing or any work of art.the important of colors is clear in
the life of every one of the people. A good color scheme in all aspect s of life is a clear
indication of a highly developed society and nation. It also has appositive effect on the
individual s by providing feeling s of joy and comfort – such feeling encourage hard work
and productivity whether at home. At school or at work.
A study of childhood and attention of the criteria by which to measure the progress
of society and its development as the interest in childhood is in fact interesting Bmstqubla
the whole nation. The current research s

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