Background: Polymethylmethacrylate (PMMA) is the most ‎commonly used mâ€aterial in denture construction. This material is ‎far from ideal in fulfilling the‎ mechanical requirements, like low impact and transverse strength and poor thermal conductivity are present in this material. The purpose of this study was to study the effect of addition a composite which include 1%wt silanized silicone dioxide nano fillers (SiO2) and 1wt% oxygen plasma treated polypropylene fiber (PP) on some properties of heat cured acrylic resin denture base material (PMMA). Materials and methods: One hundâ€red (100) prepared specimens were divided into five groups according to the tests, each group consisted of 20 specimens and these were subdivided into two groups (unreinforced heat cured acrylic resin as control group)and reinforced acrylic resin with ( 1%wt Nano SiO2 and 1% wt oxygen plasma treated polypropylene ‎fibers) ‎group. The transverse strength¸ impact ‎strength, indentation hardness (shoreD), surface roughness and water sorption and solubility were investigated. The results were statistically analyzed using descriptive and t-test. Results: The results of this study show that a highly significant increase in impact strength (10.4939 Kj/m2),surface hardness (89.9375) surface roughness (0.9498) and water sorption (0.0171mg/cm2) was observed with the addition of 1%wt silanized (SiO2) nanoparticles and 1%wt oxygen plasma treated polypropylene fibers to (PMMA) , also significant decrease in transverse strength (103.4753 N/mm2), nonsignificant decrease occurred in water solubility which was (0.0005mg/cm2). Conclusion: The incorporation of 1%wt silanized SiO2 nanoparticles and 1%wt oxygen plasma treated polypropylene fiber to heat cure PMMA form a composite improves the impact strength, surface hardness and surface roughness of acrylic resin, at the same time this addition increase the water sorption and decrease water solubility; while significant decrease in transverse strength.
A new compound 2-(4-methoxyphcnyl)-5-(4-aminophenyl)-1,3,4-
oxadiazole (VI) was prepared by intramol ecular condensation reaction followed by elimination of some simple moieties such as IhO and HCI by using POCI3 with acid hydrazide. A series of new ShiffsÂ
bases 2-(4-methoxyphenyl)-5-[4(4:alkoxybenzoyloxy) benzylidene amino phenyl] I,3,4-oxadia:t.ole (VII].was synthesized from treatment
of oxadiazole derivative [VI] with an appropriate aromatic aldehyde
(IU). Struct\lfe of the resulting products have been ascertaim:d by their melting pointS, elemental analysis ( some of them) and spectral data.
In this article four samples of HgBa2Ca2Cu2.4Ag0.6O8+δ were prepared and irradiated with different doses of gamma radiation 6, 8 and 10 Mrad. The effects of gamma irradiation on structure of HgBa2Ca2Cu2.4Ag0.6O8+δ samples were characterized using X-ray diffraction. It was concluded that there effect on structure by gamma irradiation. Scherrer, crystallization, and Williamson equations were applied based on the X-ray diffraction diagram and for all gamma doses, to calculate crystal size, strain, and degree of crystallinity. I
... Show MoreAllah Almighty has aggrandized the position of orphans and elevated their status in the society and has given the graces for those who sponsor the orphan and care for and protecting them, even those who rub their heads. The divine care is manifested in the verses of the Holy Bible and the Holy Quran. Therefore, the whole world cared for the orphan, and called for the rights of the orphans in the conferences and the channels. But all that was little effort that does not meet what the orphan need and some were only ink on paper that were not applied. All that mentioned above is necessary in dealing with the study (the rights of orphans in the Old Testament and Islam, a Comparative Study). The study was divided into a Preface and four inquirie
... Show MoreThe upbringing of Yehuda Amichai and the conditions he lived in had a great influence on his deep sense of pain, which made him think of death and suicide. Especially after the Nazis came to power in Germany, and his emigration with his family. Amichai searched for love throughout his life, and his failure was one of the most important factors affecting his psyche, which is A deep influence that made him live in harsh and painful pains that broke him, and prevented her from achieving his ambitions in life.Dramatic texts are characterized by repetition in writing and presentation. It is a textual discourse that has two advantages, first, that it can be read as a literary text like all other literary texts, and second, that it can be consider
... Show MoreCommunicating effectively by gaining productive skills in a classroom setting is one of the critical goals of learning the English language. The current study was conducted to explore the correlation of EFL learners’ level of academic intelligence with their productive skills. The study tries to find an answer to what is the correlation between EFL learners’ academic intelligence and level of production skills. The study population represents EFL students at the departments of English language of the Iraqi Colleges of Education for the academic year (2022-2023). The sample includes 310 EFL students selected from the 3rd year of the Department of English of the College of Education, Ibn-Rushd for Human Sciences/University of Bagh
... Show MoreMusic and singing are always associated with the movement of society and the emergence of cultural and artistic activities other.
The social and political transformations of the 1930s helped to disseminate the study Music and music in the city of Baghdad and across Iraq This is the beginning of a new era of musical art alongside other arts.
While achieving musical arts A new step was advanced by publishing a technical study among the younger generation they were looking for to contribute to the musical field On the other hand, the city of Baghdad during the period of research many musical and musical performances Egyptian teams have provided many artistic activities and events which have had a significant impact on the development
Warm dark matter (WDM) models offer an attractive alternative to the current cold dark matter (CDM) cosmological model. We present a novel method to differentiate between WDM and CDM cosmologies, namely, using weak lensing; this provides a unique probe as it is sensitive to all of the “matter in the beam,” not just dark matter haloes and the galaxies that reside in them, but also the diffuse material between haloes. We compare the weak lensing maps of CDM clusters to those in a WDM model corresponding to a thermally produced 0.5 keV dark matter particle. Our analysis clearly shows that the weak lensing magnification, convergence, and shear distributions can be used to distinguish
Turkish policy towards Africa witnessed important developments over time that began before the Ottoman era and then developed during the Ottoman era when the Ottoman state played an important role in maintaining security by confronting Portuguese interventions in North Africa and sending military aid. Thus, the Ottoman state was able to develop its policy towards Africa for important considerations based mainly on the employment of the religious factor and the spread of Islam for the African acceptance of the Ottomans in the African territories and thus, achieve economic, strategic and political motives. Later, these relations declined in the Republican era due to the weak political and economic potential of Turkey on the one hand and th
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