Background: Polymethyl methacrylate (PMMA) is used in denture fabrication and considered as the most reliable material for the construction of removable prosthodontic appliances. The material is far from ideal in fulfilling the mechanical requirements and the effect of autoclave processing has not been fully determined. The purpose of this study was to evaluate the effect of addition of salinized (ZrO2) Nano fillers in percentages 3%, 5% and 7% by weight on some properties of heat cured acrylic processed the by autoclave and compare it with 0% (control) group . Materials and methods: The silanized(ZrO2) Nano-particles was added to PMMA powder by weight in three different percentages 3%, 5% and 7%, mixed by probe ultra-sonication machine.Two hundred specimens were constructed and processed by autoclave and divided into 5 groups according to the test (each group consist of 40 specimens ) and each group was subdivided into 4 sub-groups according to the percentage of added (ZrO2) nano-particles( with 10 specimens for each subgroups) . The tests conducted were transverse strength, hardness (shore D), Impact strength test, surface morphology and apparent porosity. AFM can provide 3D image of the specimen the homogeneity of nanostructure film, roughness of surface and crystallite size. Scanning electron microscope SEM of control and salinized Nano ZrO2 reveal the Nano fillers distribution and it is shaped. Results: Highly significant increase in impact strength recorded when acrylic (vertex) mixed with 3%, 5% ZrO2 nano filler, while a non-significant reduction was observed with 7% ZrO2 addition in comparison to control. Non-significant improvement in transverse strength when 3% ZrO2 was added, 5% nano addition ZrO2 improved transverse strength significantly while 7% nano addition showed anon significant reduce when these groups compared to the control group .Anon significant reduction in the deformity was seen within 3% nano addition ZrO2 also 5% nano ZrO2 addition reduce the deformity significantly and significant increase was recorded when 7% nano addition ZrO2 was add and when these groups are compared to the control group. A significant increase in surface hardness was observed with the addition of (ZrO2) nano-particles to (PMMA) at the percentage of 3%, highly significant increase at 5% and 7% with addition of modified nano-ZrO2. A non-significant decrease in apparent porosity at 3% and highly significant decrease in apparent porosity at 5% and 7% with addition of modified nano-ZrO2 were observed. SEM results showed a good distribution of the modified nano-ZrO2 fillers at 3%, 5% and showed aggregation at 7% in the polymer matrix. Conclusion: The addition of modified nano-ZrO2 particles to acrylic resin cured by autoclave improved impact and transverse strength of denture base nano composite containing 5% of nano-ZrO2. And this strength decreases with further increase of nano-ZrO2 filler content. Also addition of modified nano-ZrO2 slightly increaseshardness, thesurface roughness and the apparent porosity also decrease by addition of nano ZrO2 percentage increase. Key words: Salinized (ZrO2) nano fillers, PMMA.
The probability is considered one of the grammatical cases in all languages of the world. Expressions of probability in Spanish language are expressed by various structures, expressions and some verb tenses. By this study explains the grammatical cases, the verbal periphrases, the impersonal expressions, the future tenses (simple and perfect) and the conditional mode of probability in Spanish language .We have explains these cases in detail with examples that have extracted from various spanish grammar books .The specific objective of this study is to know the resources and constructions of probability in Spanish language and their translation in Arabic language.
The new organic reagent 2-[Benzo thiazolyl azo]-4,5-diphenyl imidazole was prepared and used as complexing agent for separation and spectrophotometric determination of Cu2+ ion in some samples include plants, soil, water and human blood serum. Initially determined all factors effect on extraction method and the results show optimum pH was (pHex=9), optimum concentration was 40?g/5mLCu2+ and optimum shaking time was (15min.), as well stoichiometry study appears the complex structure was 1:1 Cu2+: BTADPI. Interferences effect of cations were studied. Synergism effect shows MIBK gave increasing in distribution ratio (D). Organic solvent effect appears there is no any linear relation between dielectric constant for organic solvent used and dis
... Show MoreDiabetic mellitus is one of the main risk factors of fungal infections because poor glycemic control is associated with a high level of glucose in blood and saliva which could be treated as nutrient to fungi. This study aimed to isolate and identification of pathogenic fungi from diabetic patient. 140 samples were taken from different places of human body from the national center of diabetic patients that related to Mustansiriyah University / college of medicine and Al-yarmuk Hospital in Baghdad. 84 sample (60%) tested positive to fungi and 56 sample (40%) tested negative to fungi. The most frequented fungi isolated have been chosen for molecular identification by PCR (Millerozyma farinosa and Candida orthopsilosis) using specific pri
... Show MoreObjective(s): To assess mothers’ knowledge about their children with sickle cell anemia and non-Pharmacological approaches to pain management and found some relationship between mothers knowledge and their demographic data of age, level of education, and occupation.
Methodology: A descriptive design used in the present study established was for a period from September 19th, 2020 to March 30th, 2021. The study was conducted on a non-probability (purposive) sample of (30) mother their children with sickle cell anemia was chosen. The data were analyzed through the application of descriptive and inferential statistical approaches which are applied by using SPSS version 22.0.
Results: The findings of the study indicated that moderate
The current study was to examine the reliability and effectiveness of using most abundant, inexpensive waste in the form of scrap raw zero valent aluminum ZVAI and zero valent iron ZVI for the capture, retard, and removal of one of the most serious and hazardous heavy metals cadmium dissolved in water. Batch tests were conducted to examine contact time (0-250) min, sorbent dose (0.25-1 g ZVAI/100 mL and 2-8 g ZVI/100 mL), initial pH (3-6), pollutant concentration of 50mg/L initially, and speed of agitation (0-250) rpm . Maximum contaminant removal efficiency corresponding to (90 %) for cadmium at 250 min contact time, 1g ZVAI/ 6g ZVI sorbent mass ratio, pH 5.5, pollutant concentration of 50 mg/L initially, and 250 rpm agitation speed wer
... Show MoreWith the fast-growing of neural machine translation (NMT), there is still a lack of insight into the performance of these models on semantically and culturally rich texts, especially between linguistically distant languages like Arabic and English. In this paper, we investigate the performance of two state-of-the-art AI translation systems (ChatGPT, DeepSeek) when translating Arabic texts to English in three different genres: journalistic, literary, and technical. The study utilizes a mixed-method evaluation methodology based on a balanced corpus of 60 Arabic source texts from the three genres. Objective measures, including BLEU and TER, and subjective evaluations from human translators were employed to determine the semantic, contextual an
... Show MoreThe gas sensing properties of Co3O4and Co3O4:Y nano structures were investigated. The films were synthesized using the hydrothermal method on a seeded layer. The XRD, SEM analysis and gas sensing properties were investigated for Co3O4and Co3O4:Y thin films. XRD analysis shows that all films are polycrystalline in nature, having a cubic structure, and the crystallite size is (11.7)nm for cobalt oxide and (9.3)nm for the Co3O4:10%Y. The SEM analysis of thin films obviously indicates that Co3O4possesses a nanosphere-like structure and a flower-like structure for Co3O4:Y.The sensitivity, response time and recovery time to a H2S reducing gas were tested at different operating
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