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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 Physics
Optical Properties of GaN Thin Flim
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GaN thin films were deposited by thermal evaporation onto
glass substrates at substrate temperature of 403 K and a thickness of
385 nm . GaN films have amorphous structure as shown in X-ray
diffraction pattern . From absorbance data within the range ( 200-
900 ) nm direct optical energy gap was calculated . Also the others
optical parameters like transmittance T, reflectance R , refractive
index n , extinction coefficient k , real dielectric constant 1 Î , and
imaginary dielectric constant 2 Î were determined . GaN films
have good absorbance and minimum transmittance in the region of
the visible light .

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Publication Date
Sun Jul 09 2023
Journal Name
Journal Of Engineering
Reaction Kinetics of Tert-Butanol Esterification
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In this study, the kinetics for the reaction of tert-butanol esterification with acetic acid in the presence of Dowex 50Wx8 catalyst was investigated. The reaction kinetic experiments were conducted in 1000 milliliter vessel at temperatures ranged from 50 - 80 oC, catalyst loading 25-50 g/L, and the molar ratios of acetic acid to tert-butanol from 1/3 – 3/1. The reaction rate was found to increase with increasing temperature and catalyst loading. It was also found the conversion of the tert-butanol increases as the molar ratio of acid to alcohol increases from 1/3 – 3/1. The Non-ideality of the liquid phase was taken into account by using activities instead of molar fractions. The activity coefficients were calculated according to th

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Publication Date
Fri Apr 20 2018
Journal Name
Iaes International Journal Of Artificial Intelligence (ij-ai)
Optimization of Digital Histopathology Image Quality
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One of the biomedical image problems is the appearance of the bubbles in the slide that could occur when air passes through the slide during the preparation process. These bubbles may complicate the process of analysing the histopathological images. The objective of this study is to remove the bubble noise from the histopathology images, and then predict the tissues that underlie it using the fuzzy controller in cases of remote pathological diagnosis. Fuzzy logic uses the linguistic definition to recognize the relationship between the input and the activity, rather than using difficult numerical equation. Mainly there are five parts, starting with accepting the image, passing through removing the bubbles, and ending with predict the tissues

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Publication Date
Sat Sep 21 2019
Journal Name
Journal Of The College Of Education For Women
Problems Facing the Teachers of Kindergartens
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The research aims at:

  1. Identifying the problems facing kindergarten teachers.
  2. Identifying the nature of the problems facing kindergarten teachers.

To achieve the aim of the research, the researcher prepared a questionnaire to identify the problems that face the teachers of kindergartens. The questionnaire was subjected to the consultation of a group of specialized expertise in the educational and psychological sciences to certify the propriety of the items of the questionnaire and it gained a rate of (80%), and the stability of the scale gained (0.91) and it stands for a correlation parameter with a statistical significance and it was calculated by using Person’s R Corre

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Publication Date
Wed Dec 14 2016
Journal Name
Journal Of Baghdad College Of Dentistry
Immunohistochemical Expression of Endocan in Ameloblastoma
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Background: Ameloblastoma is the most common clinically significant odontogenic tumor, known for its locally invasive potential and frequent recurrences unless treated radically. Endocan is a soluble proteoglycan which is reported to have prognostic implications in multiple human diseases and tumors. This study aims to describe the expression of endocan in ameloblastoma. Materials and methods: With immunoperoxidase method; tissue sections of formalin fixed- paraffin embedded blocks for ameloblastomas were stained with monoclonal antibodies to endocan, the localization of the endocan expression was examined and the resulting scores of the tissue sections were analyzed according to age, sex, site and tumor subtype. Results: endocan was found

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Crossref
Publication Date
Fri Sep 01 2023
Journal Name
Journal Of Engineering
Kinetics of Fixed Bed Sorption Processes
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Adsorption and ion exchange are examples of fixed-bed sorption processes that show transient behavior. This means that differential equations are needed to design them. As a result, numerical methods are commonly utilized to solve these equations. The solution frequently used in analytical methods is called the Thomas solution. Thomas gave a complete solution that adds a nonlinear equilibrium relationship that depends on second-order reaction kinetics. A computational approach was devised to solve the Thomas model. The Thomas model's validity was established by conducting three distinct sets of experiments. The first entails the adsorption of acetic acid from the air through the utilization of activated carbon. Following

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Crossref
Publication Date
Tue Oct 10 2023
Journal Name
Journal Of Craniofacial Surgery
CBCT Analysis of Oropharynx Airway Volume
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Objective:

The study was performed to analyze the oropharynx airway and examine the influence of age and gender on the oropharynx volume configuration using cone beam computed tomography.

Materials and Methods:

This study examined the cone beam computed tomographic images of 51 patients 25 male and 26 females, group matched for age and gender. The oropharynx airway volume and area between the posterior nasal spine and top of the epiglottis were measured and compared.

Results:
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Publication Date
Sat Jul 01 2017
Journal Name
Global Journal Of Bio-science And Biotechnology
Efficiency of different denture disinfection methods
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Dentures that are not cleaning and maintained properly may prone to contamination by different microbial pathogens that result in several oral conditions. This study was design to compare the antimicrobial effect of different denture cleansers oxalic, tartaric, citric acids and alkaline peroxide with microwave irradiation on the growth of Candida albicans and Staphylococcus aureus respectively. Microwave oven used to disinfect specimens of heat-activated acrylic resin and soft linear. Oxalic, citric, tartaric acids, and alkaline peroxide were also used. Microorganisms that tested were Candida albicans and Staphylococcus aureus separately. Treatment with microwave or tartaric acid could achieve sterilization of both hot cured acrylic resins

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Publication Date
Fri Oct 01 2010
Journal Name
Iraqi Postgraduate Medical Journal
Frequency of genodermatoses among Iraqi patient
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HR Al-Hamami, AA Noaimi, MM Al-Waiz, AS Al-Kabraty, Iraqi Postgraduate Medical Journal, 2010 - Cited by 4

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Publication Date
Fri Oct 01 2010
Journal Name
Journal
Frequency of genodermatoses among Iraqi patients
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AH Haider R, N Adil A, AW Makram M, AK Abdulkaleq S, 2010

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