Polyvinyl alcohol, (PVA) was prepared using polyvinyl acetate emulsion (manufactured by Al-Jihad factory,
That-Al-Sawary Company) as a local raw material. In this investigation, polyvinyl acetate emulsion was converted to
solid form by coagulation the polymer from its emulsion using sodium sulphate salt as coagulant aid, then alcoholyzed
the solid polyvinyl acetate in methanol using sodium hydroxide as catalyst, polyvinyl alcohol produced by this method is
a dry, white to yellow powder.
Three affecting variables on the degree of hydrolysis of PVA were studied, these variable are Catalyst to
polymer weight ratio in the range of 0.01 – 0.06, reaction time in the range of 20 – 90 min, and reaction temperature in
the range of 25 – 50 oC. The effect of degree of hydrolysis of PVA produced on its properties such as water solubility
and degree of polymerization were studied also.
Finally the alcoholysis reaction kinetics were studied to determine the reaction constants such as initial rate
constant and degree of autocatalytic effect of the alcoholysis reaction. It was found that the degree of hydrolysis of
formed polyvinyl alcohol increase with increasing of variables catalyst concentration, reaction time and reaction
temperature, furthermore, the water solubility of PVA increase with increasing degree of hydrolysis up to about 87 %
after this value the solubility is decrease, also the degree of polymerization of PVA decrease with increasing of degree of
hydrolysis up to about 89 %.
The purpose of this study is to illuminate the role of CBCT in forensic dentistry through variations of mandibular measurements of Bonwill’s triangles in gender determination among the Iraqi population.
In this retrospective study 70 CBCT scans were analyzed to measure the Bonwill’s triangle, 35 for males and 35 for females aged between 20 and 50 years, all data were collected at the oral and maxillofacial radiology department in Ghazi AL-Hariri hospital for 3 months, and the data were obtained using a Kavo CBCT device (3D On De
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Background: A Catheter-associated with candidiasis infection is the most common nosocomial infection and the objective of this work is to isolate and identify Candida species from catheterized patients by ordinary culture and PCR.Objective:To study the isolation and identification of Candida species from catheterized patients by culture media and polymerase chain reaction(PCR).Methods: One hundred and thirty five Candida species isolates were obtained from urine culture of catheterized specimens from male and female patients , During the period between October 2011 to April 2012 , attending AL-Ramadi general teaching Hospital. A quantitative urine culture for isolation and identification of Candida species was. The isolation of Candida s
... Show MoreThis research aims to solve the problem of selection using clustering algorithm, in this research optimal portfolio is formation using the single index model, and the real data are consisting from the stocks Iraqi Stock Exchange in the period 1/1/2007 to 31/12/2019. because the data series have missing values ,we used the two-stage missing value compensation method, the knowledge gap was inability the portfolio models to reduce The estimation error , inaccuracy of the cut-off rate and the Treynor ratio combine stocks into the portfolio that caused to decline in their performance, all these problems required employing clustering technic to data mining and regrouping it within clusters with similar characteristics to outperform the portfolio
... Show MoreHepatitis B virus (HBV) infection is a significant global health problem. Populations of different ethnicities show great heterogeneity in HBV genotype frequency distributions. A cross-sectional study was conducted during June–October 2018 to determine frequency of HBV genotypes among chronic HBV patients from Baghdad, Iraq. The method of detection was nested polymerase chain reaction system. Further, the study assessed the impact of HBV genotypes on serum level of liver-function tests: total serum bilirubin, alkaline phosphatase, alanine aminotransferase and aspartate aminotransferase. Eighty chronic HBV patients were enrolled in the study. Six HBV genotypes were identified (A, B, C, D, E and F). The most frequently encountered genotypes
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Education by lectures has been standard for 100 years or more. Given the 21st century technology, people can connect with others around the world instantly, electronically. With the pandemic, teaching changed to one-way information transfer with the loss of interpersonal learning experience. SNI® and now SNI Digital™ have been experimenting with different forms of communication to transfer information.
Using an interactive education model, a meeting for neurosurgeons in Baghdad was held for students, residents, and neurosurgeons
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Five subsurface sections covering the entire length of the Jeribe Limestone Formation (Early Middle Miocene) were studied from four oilfields in northern Iraq. It is hoped to unravel this formation microfacies ; depositional environment; diagenetic attributes and their parental processes; and the relationship between these processes and the observed porosity patterns. The microfacies were found to include mudstone, wackestone, packstone, and grainstone, which have been deposited respectively in open platform, restricted platform, and edge platform which represent the lagoonal environment, while the deposits of the lower parts of the Jeribe formation especially in well Hamrin- 2 reflect a deeper fore slope environment. By using the lithofac
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This research concentrate on cultivated Iraqi Agave attenuata dried leaves and roots, because of little studies on this plant especially on the root that lead to the eager of study and comparison of phytochemical constituents between leaves and root. Extraction of bioactive constituents was carried out using several solvents with increasing polarity (n-hexane, ethyl acetate and methanol) by soxhlet apparatus. Steroidal saponins in Agave genus is well documented in many species, lightening the minds in this research on extraction method which is specific for steroidal saponins. Phytochemical screening was done by GC/MS for n-hexane fraction, qualitative and quantitative estimation of several bioactive constituents (caffe
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