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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This research sheds light on the contributions of a group of scientific Kurdish scholars in the seventh and eighth Hijri centuries, who devoted themselves to serving science with the bad political and economic conditions at the time, and the research pointed to the flowering of science and how students travel in order to provide them with science, obtain a scientific certificate, then take up The research efforts of the scholars in the two Hijri century mentioned in the science of the Qur’an, whether in the field of recitations, intonation or interpretation, and the research ends with a conclusion in which I mentioned the most important conclusions reached in this research.
In light of the increasing importance of interim financial statements they provided these lists of information that enables users of accounting information to make wise investment decisions and predict the company's activities in light of changes the updated rather than wait until the end of the year and accessing information provided by the annual financial statements. In light of this research has come to the most important set of conclusions the adoption of interim financial information has been audited by the external auditor to the availability of basic qualitative characteristics in the accounting information contained in the (appropriate and timely manner, reliability and comparability) and this in turn leads to the impact on reli
... Show MoreThe herein research was carried out in order to identified the presence of bacteria in cervix and uterine lumen in Iraqi cattle during the different estrus phase with focusing on Protus and E coli. Estrus phases were determined by the structures which found on ovary (follicular growth for pro-estrus, mature growing follicle for estrus, hemorrhagic corpus luteam for meta-estrus and active corpus luteam for di-eatrus). Forty cervical swabs (ten for each estrus phase) and forty uterine swabs (ten for each estrus phase) were taken from macroscopically healthy reproductive animals after slaughtering and cultivated on nutrient agar and blood agar, the bacterial isolation were identified with biochemical teats. The present study found that
... Show MoreIn this paper, several conditions are put in order to compose the sequence of partial sums , and of the fractional operators of analytic univalent functions , and of bounded turning which are bounded turning too.
In this research, the preparation of bidentate Schiff base was carried out via the condensation reaction of both the salicylaldehyde with 1-phenyl-2,3-dimethyl-4-amino-5-oxo-pyrazole to form the ligand (L). The mentioned ligand was used to prepare complexes with transition metal ions Mn(II), Co(II), Ni(II), Cu(II) and Zn(II). The resulting complexes were separated and characterized by FTIR and UV-Vis spectroscopic technique. Elemental analysis for Carbon, Hydrogen and Nitrogen elements, electronic spectra of the ligand and complexes were obtained, and the magnetic susceptibility tests were also achieved to measure the dipole moments. The molar conductivities were also measured and determination of chlorine content in the complexes and
... Show MoreText science presented a set of criteria to make the text essentially a project to create
texts and use. Me and means of cohesion script text scientists, two standard foundries and
knitting. Find this means their equivalent in the Arab rhetorical Heritage has been found, it
means foundries find Accompanying represented (link grammar in the classroom and link),
and referrals represented by (Baldmair, Ldefinition, and the name of the signal), and
deletion, and repetition, and presentation delays. As in the standard knitting it has confirmed
Albulagjun Arabs on the semantic consistency between the text components, as reflected in
the moral link in Chapter interfaces, as well as in moral coherence between parts of the te
This research deals with the study of pathways in terms of the negative effect in proving them
And the fact of this influence among fundamentalists.
The research consists of two subjects and a conclusion.
In the first section, I learned about the terms in the title of the research:
Denial and pathology.
In the second section I reviewed the pathways of illness that affect exile in it
Five: the nodding, the fitting, the sounding, the division, the rotation, the inference
A description of the absence of evidence of non-reference to it. And I figured out how
Negation in it by striking some illustrative examples as fruit
Arising from the effect of negation in proving those routes.
As a result of this research, a
This study aims to explain the purposes of thinking in light of the Holy Qur’an. The study adopted the deductive method by analyzing the meanings of the eighteen thinking verses mentioned in the Holy Qur’an That is by referring to the ancient and contemporary book interpretations and inferring the purposes of thinking from the context of those verses. The study concluded that there are seven main purposes, for thinking in the light of the Holy Qur’an, are understanding the universal regulations, contemplating the social codes, inferring, extracting maxims and meanings from the Qur’anic proverbs, analyzing the situation objectively, balancing between interests and evils, and freeing the mind from the authority of the paranormal. T
... Show MoreAbstract: In this paper, a U-shaped probe with a curvature diameter of half a centimeter was implemented using plastic optical fibers. A layer of the outer shell of the fibers was removed by polishing to a D-section. The sensor was tested by immersing it in a sodium chloride solution with variable refractive index depending on solution concentrations ranging from 1.333 to 1.363. In this design, the sensor experienced a decrease in its intensity as the concentration of the solution increased. The next step The sensor was coated with a thin layer of gold with a thickness of 20 nm, and the sensor was tested with the same solutions which resulted in a shift in wavelengths where the shift in wavelength was 5.37 nm and sensiti
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