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 %.
Dental clinicians and professionals need an affordable, nontoxic, and effective disinfectant against infectious microorganisms when dealing with the contaminated dental impressions. This study evaluated the efficiency of hypochlorous acid (HOCl) as an antimicrobial disinfectant by spraying technique for the alginate impression materials, compared with sodium hypochlorite, and its effect on dimensional stability and reproduction of details. HOCl with a concentration of 200 ppm for 5 and 10 min was compared with the control group (no treatment) as a negative control and with sodium hypochlorite (% 0.5) as a positive control. Candida albicans, Staphylococcus aureus, and Pseudomonas aeruginosa were selected to assess the antimicrobi
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The inhibitory behavior of L-Cysteine (Cys) and its derivatives towards iron corrosion through density functional theory (DFT) was investigated. The current research study undertakes a rigorous evaluation of global as well as local reactivity descriptors of the Cys in protonated as well as neutral forms and the changes in reactivity after the combination of Cys into di- and tripeptides. The inhibitory effect of di- and tri-peptides increases since, in the molecular structure, the number of reaction centers increase. We computed the adsorption energies (Eads) and low energy complexes with most stability for the adsorption of small peptides and Cys amino acids onto the surfaces of Fe (1 1 1). We found that the adsorption of tri-peptides onto
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In this study, a different design of passive air Solar Chimney(SC)was tested by installing it in the south wall of insulated test room in Baghdad city. The SC was designed from vertical and inclined parts connected serially together, the vertical SC (first part) has a single pass and Thermal Energy Storage Box Collector (TESB (refined paraffin wax as Phase Change Material(PCM)-Copper Foam Matrix(CFM))), while the inclined SC was designed in single pass, double passes and double pass with TESB (semi refined paraffin wax with copper foam matrix) with selective working angle ((30o, 45o and 60o). A computational model was employed and solved by Finite Volume Method (FVM) to simulate the air i
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The absence of ecological perception in the local urbanization resulted in the lack of a clear conception of achieving sustainability in its simplest form in the urban reality and in the city of Baghdad in particular. The research assumes the possibility of achieving urban sustainability in Iraqi cities by applying the cities for the most effective methods to implemented ecological solutions and introducing appropriate urban planning tools and improve the living environment. The research focuses on the ability to define some aspects to achieve a sustainable local urban identity from global experiences. This was performed by proposing a scheduled theoretical framework, through which the features of sustainability can be extrapolated from the
... Show MoreThe Local manufacturing scanning gamma system designed in Tuwaitha site for nondestructive assay method of radioactive waste drums, where it consist of two main parts with their belongings for controlling the of detector and drum movements up-down and rotation respectively. The volume of the used drum is 220 L with 85 cm height. The drum filled with Portland cement. Six cylindrical holes were made within cement drum and distributed in radial arrangement.The152Eu source inserted in these holes individually, to measure the average angular count rate of gamma radiation. The full energy efficiency value for geometry of drum and detector is computed for thirteen photo peaks. The average efficiency represented by the curve of these peaks indic
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Sorting and grading agricultural crops using manual sorting is a cumbersome and arduous process, in addition to the high costs and increased labor, as well as the low quality of sorting and grading compared to automatic sorting. the importance of deep learning, which includes the artificial neural network in prediction, also shows the importance of automated sorting in terms of efficiency, quality, and accuracy of sorting and grading. artificial neural network in predicting values and choosing what is good and suitable for agricultural crops, especially local lemons.
In this study, the investigation of flavorings used in 567 model of local food products and imported in our local markets through information contents cards media shoddy standard Iraqi has been found that foods that appeal to children of sugar confectionery and Crapt and other barely Atkhalo of flavorings used that lead tohealth risks
Specialized Escherichia coli (E. coli) isolates, called uropathogenic E. coli (UPEC), cause most of urinary tract infections (UITs). Once bacteria reached the urinary tract of the host, they have to adhere to the host cell for the colonization. For this purpose, bacteria have different structures including fimbrial adhesins. Most of the UPECs contain type 1 fimbriae encoded by fim operon (fimB, E, A, I, C, D, F, G, H) which is responsible for the adhesive ability in these isolates. Ninety-four isolates of UPEC were obtained from UTI patients in Baghdad hospitals and their diagnosis were confirmed by the PCR method using 16srDNA as a housekeeping gene. The UPEC isolates were tested for their ability of adherence to the urothelial cells obtai
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Morphometric traits or body conformation traits also called linear body measurements are important in predicting marketing body weight especially for commercial breeders and producers. The total number of reared Domyati ducklings are 168 hatched, at marketing age (8 wks.) 44 brown and 14 white Domyati ducks were used to estimate the body weight and body measurements such as shank length (ShL), keel length (KL), body circumference (BC), breast length (BrL), breast width (BrW), beak width (BL), and body length (BL). Our results showed that there is no significant difference between both white and brown Domyati ducks for body measurements. There was high positive correlation among body weight and body measurements on both white and bro
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