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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Bearing capacity of soil is an important factor in designing shallow foundations. It is directly related to foundation dimensions and consequently its performance. The calculations for obtaining the bearing capacity of a soil needs many varying parameters, for example soil type, depth of foundation, unit weight of soil, etc. which makes these calculation very variable–parameter dependent. This paper presents the results of comparison between the theoretical equation stated by Terzaghi and the Artificial Neural Networks (ANN) technique to estimate the ultimate bearing capacity of the strip shallow footing on sandy soils. The results show a very good agreement between the theoretical solution and the ANN technique. Results revealed that us
... Show MoreAl-Aziz's book was chosen as a subject for research as it is one of the important books in the Islamic world in general and the Shafi'i school in particular and its author Imam Abdul Karim bin Mohammed bin Abdul Karim Al-Rafi's, who in the doctrine of the jurisprudence has made prominent lines and left behind invaluable scientific treasures in the service of religion. Its importance is summarized as follows:
1. Being an explanation of the book (brief) of the argument of Islam Imam Ghazali (God's mercy), one of the five books adopted in Shafi'i jurisprudence.
2. His work is Imam Abu al-Qasim al-Rafii known for the brilliance of the investigation and the power of weighting in the doctrine.
3. It is considered an encyclopedia in Sh
: The terrestrial snail Eobania vermiculata (O. F. Müller, 1774) were collected from three station in Baghdad Al- Karkh, Iraq between the period from June 2016 to July 2017. Then we studied the life cycle from the egg to maturity. We studied and photographed the external morphology of it’s shell to identified the species. This species was recorded for the first time in Baghdad.
This study is conducted to determine the activity of plant Vica faba and two isolated from arbuscular mycorrhizae fungi (A,B) in bioremediation of soil pollution by Nickel and Lead elements in north and south of Baghdad city. The results showed that the average of soil pollution by Nickel and Lead elements in north of Baghdad was less than the average of soil pollution in the south of Baghdad which recorded 29.0,9.0PPm and 42.0, 25.0PPm respectively. The results show that the isolate A from the polluted soil is more active from isolate B which isolate from unpolluted soil for bioremediation. Vica faba recorded more in accumulate the Lead element in shoot system which was 19.65PPm and in root system was 27.2PPm and for Nickel element 24.65
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Circular thin walled structures have wide range of applications. This type of structure is generally exposed to different types of loads, but one of the most important types is a buckling. In this work, the phenomena of buckling was studied by using finite element analysis. The circular thin walled structure in this study is constructed from; cylindrical thin shell strengthen by longitudinal stringers, subjected to pure bending in one plane. In addition, Taguchi method was used to identify the optimum combination set of parameters for enhancement of the critical buckling load value, as well as to investigate the most effective parameter. The parameters that have been analyzed were; cylinder shell thickness, shape of stiffeners section an
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