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An Evaluation of Some Mechanical Properties of Autopolymerizing Acrylic Resin with the Modified One after Changing the Curing Environment: (In vitro Study)
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Background: Studying and investigating the transverse strength(Ts), impact strength(Is), hardness (Hr) and surface roughness(Ra) of conventional and modified autopolymerizing acrylic resin with different weight percentages of biopolymer kraftlignin, after curing in different water temperatures; 40°C and 80°C. Material and Methods: Standard acrylic specimens were fabricated according to ADA specification No.12 for transverse strength, ISO 179 was used for impact testing, Shore D for hardness and profilometerfor surface roughness. The material lignin first dispersed in the monomer, then the powder PMMA is immediately added. Ligninadded in different weight percentages. Then cured using pressure pot (Ivomet) in two temperatures;40°C and 80°C under 2 bar pressure, for 30 minutes.Atotal of 144samples were prepared for this study. Ts, Is, Ra, and Hr were tested, by using Instron universal testing machine, charpy impact tester, shore D tester, and profilometer respectively. Results: The transverse strength increased in both the conventional and modified onewhen compared with that cured in air. The addition of 0.5wt% lignin gave the higher effect (78.0017MPa) with highly significant difference found between groups at 40°C polymerizing temperature. While the impact strength in both temperatures in the modified resin revealed increased results than conventional one, 1.25wt% of kraft lignin gave the highest value (12.7355KJ/m2) with highly significant differences found between groups at 80°C polymerizing temperature. Hardness and surface roughness showed also highly significant differences found between groups at 40°C polymerizing temperature, all the groups had increased Hr. than the control one (78.95), while the Ra. decreased for 1.0% ,1.25,1.50 and 1.75 wt% lignin content to (0.26,0.10,0.063, 0.12µm) respectively in 40°C polymerizing temperature, the lowest value present in 1.75 wt% lignin (0.05 µm) at 80°Cpolymerizing temperature. Conclusions: It seems that increasing the polymerizing temperature to 40°C had a positive effect on the mechanical properties of autopolymerizing acrylic resin and the one enforced by kraft lignin biopolymer in low percentages. Increasing the polymerizing temperature to 80°C will doesn’t have much positive effect but it doesn’t deteriorate the mechanical properties. However, when submitted to increasing the temperature to 80°C, specimens showed a significant increase in impact strength.

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Publication Date
Wed Jun 01 2022
Journal Name
Civil And Environmental Engineering
Effect of Alkali - Activated Natural Pozzolan on Mechanical Properties of Geopolymer Concrete
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As an alternative to Ordinary Portland Cement (OPC), the alkali-activated binders have been developed with better technical characteristics and more extended durability. The Alkali-Activated Iraqi Natural Pozzolans (AANP) could produce geopolymer cementation building materials and make them ecologically acceptable. The primary advantage of geopolymer cement is that it has a lower environmental effect that contributes to it. The engineering characteristics of geopolymer concrete produced using activated Iraqi natural Pozzolan are summarized in this research. The mechanical properties, modulus of elasticity, and ultrasonic pulse velocity of various concrete mixes were determined via experimental study. The impact of essential variables like w

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Publication Date
Thu Jul 01 2021
Journal Name
Review Of International Geographical Education (rigeo)
Walkability as one of the Planning Treatments to Face Epidemics in Cities
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Walkability as one of the Planning Treatments to Face Epidemics in Cities

Publication Date
Sun Mar 07 2010
Journal Name
Baghdad Science Journal
Evaluation for the Effect of Heat Stable Enterotoxin (a) Produced by Enterotoxigenic Escherichia coli on Different Cancer Cells In Vitro
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This study was conducted for evaluating the cytotoxic effect of heat stable enterotoxin a (STa) produced by enterotoxigenic Escherichia coli on the proliferation of primary cancer cell cultures, obtained from tumor samples that were collected from (13) cancer patients and as follows: (five colon cancer patients, two bladder cancer patients, two breast cancer patients, two stomach cancer patients and two lung cancer patients), and on normal cell line (rat embryonic fibroblast / REF) (in vitro) with the use of different concentrations starting from (1) mg/ml and ending with (0.0002) mg/ml by making two fold serial dilutions by using the 96- well microtiter plate, and in comparison with negative (PBS) and positive (MMC, at concentration

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Publication Date
Wed Feb 05 2020
Journal Name
Political Sciences Journal
“The constitutional- political structures in Iraq after 2003”
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It is obvious that the constitutional- political structures which has been emerged in Iraq after the occupation in 2003 frame worked by many sectarian, ethnic, tribal and political orientations, pushing forewords to escalating the contradictions between social- political powers, however, these changes unfortunately result not just destroy and taking apart the political regime and his authority, but the state and his institutions as well, although, did not stamped as wise and rational change for better future to new Iraq and its political, civil and military institutions. Finally, as quick as Iraq start to bisects to sectarian, ethnic and national components according to the new political – social components of Iraq. Indeed, what is req

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Publication Date
Tue Mar 28 2023
Journal Name
International Journal Of Dentistry
The Effect of Different Obturation Techniques in Primary Teeth on the Apical Microleakage using Endoflas: A Comparative In Vitro Study
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Objectives. This study was carried out to quantitatively evaluate and compare the sealing ability of Endoflas by using differentobturation techniques. Materials and Methods. After 42 extracted primary maxillary incisors and canines were decoronated, theircanals were instrumented with K files of size ranging from #15 to #50. In accordance with the obturation technique, the sampleswere divided into three experimental groups, namely, group I: endodontic pressure syringe, group II: modified disposable syringe,and group III: reamer technique, and two control groups. Dye extraction method was used for leakage evaluation. Data wereanalyzed using one-way ANOVA and Dunnett’s T3 post hoc tests. The level of significance was set at p<0:05. Results.

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Publication Date
Wed Mar 13 2019
Journal Name
Al-khwarizmi Engineering Journal
Investigation Microwave Furnace Effects on Mechanical Properties and Fatigue Life of AA 7075-T73 with Dry and Acid Treatments
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Microwave heating is caused by the ability of the materials to absorb microwave energy and convert it to heat. The aim of this study is to know the difference that will occur when heat treating the high strength aluminum alloys AA7075-T73 in a microwave furnace within different mediums (dry and acidic solution) at different times (30 and 60) minutes, on mechanical properties and fatigue life. The experimental results of microwave furnace heat energy showed that there were variations in the mechanical properties (ultimate stress, yielding stress, fatigue strength, fatigue life and hardness) with the variation in mediums and duration times when compared with samples without treatment. The ultimate stress, yielding stress and fatigue streng

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Publication Date
Tue Oct 02 2018
Journal Name
Iraqi Journal Of Physics
Study the effect of thermal annealing on some physical properties of thin Cu2SiO3 films prepared by pulsed laser deposition
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The Cu2SiO3 composite has been prepared from the binary compounds (Cu2O, and SiO2) with high purity by solid state reaction. The Cu2SiO3 thin films were deposited at room temperature on glass and Si substrates with thickness 400 nm by pulsed laser deposition method. X-ray analysis showed that the powder of Cu2SiO3 has a polycrystalline structure with monoclinic phase and preferred orientation along (111) direction at 2θ around 38.670o which related to CuO phase. While as deposited and annealed Cu2SiO3 films have amorphous structure. The morphological study revealed that the grains have granular and elliptical shape, with average diameter of 163.63 nm. The electrical properties which represent Hall effect were investigated. Hall coeffici

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Publication Date
Sun Mar 01 2020
Journal Name
Baghdad Science Journal
Evaluation of Some Trace Elements Pollution in Sediments of the Tigris River in Wasit Governorate, Iraq
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The main objectives of present study are to evaluate the trace elements pollution in the sediment of the Tigris River and drainage canals in Wasit Governorate, Iraq. Assessment of trace elements pollutants were conducted for 18 sediment samples collected in March 2017. Trace elements were analyzed in sediment Tigris River samples in Wasit Governorate. This metal pollution was evaluated using geo-accumulation (I-geo) index, Contamination Factor (CF) and Pollution Load Index (PLI). According to  these statistical indices, the sediments collected from Tigris River in the study area are highly polluted with Titanium (71.9 ppm), Nickel (226.6 ppm) Chromium (425.2 ppm), Cadmium (2ppm) and Molybdenum (15.8 ppm) while  the sediments&nb

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Publication Date
Sun Jul 30 2023
Journal Name
Iraqi Journal Of Science
A Mathematical Modelling of a Plant-Herbivore Community with Additional Effects of Food on the Environment
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     By taking into account various food components in the ecosystem, the research intends to develop a set of difference equations to simulate a plant-herbivore interaction of Holling Type II. We determine the local stability of the equilibrium points for the scenarios of extinction, semi-extinction (extinction for one species), and coexistence using the Linearized Stability Theorem. For a suitable Lyapunov function, we investigate theoretical findings to determine the global stability of the coexisting equilibrium point. It is clear that the system exhibits both Flip and Neimark-Sacker bifurcation under particular circumstances using the central manifold theorem and the bifurcation theory. Numerical simulations are

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Publication Date
Fri Dec 24 2021
Journal Name
Iraqi Journal Of Science
The Optimum Site Selection for Solar Energy Farms using AHP in GIS Environment, A Case Study of Iraq
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    Recently, renewable energy (RE), such as solar energy, sources have proven their importance as an alternative source of fuel. The utilizing of solar energy can contribute to move the world towards relying on clean energy to curb global warming. However, the placement of solar farms is a major priority for planners as it is a critical factor in the succession energy project. This study combines one of the multi-criteria decision-making techniques Analytic Hierarchy Process (AHP) and Geographic Information System (GIS) to assess the suitability of land for establishing solar farms in Iraq. Numerous climatic, geomorphological, economic, and environmental criteria and some exclusionary constraints have been adopted in mode

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