Preferred Language
Articles
/
jbcd-632
The effect of addition nano particle ZrO2 on some properties of autoclave processed heat cure acrylic denture base material
...Show More Authors

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.

View Publication Preview PDF
Quick Preview PDF
Publication Date
Tue Oct 20 2020
Journal Name
Indian Journal Of Forensic Medicine & Toxicology
Biological Activity of Complexes of Some Amino Acid
...Show More Authors

Biological Activity of Complexes of Some Amino Acid

Publication Date
Mon Jan 01 2001
Journal Name
University Of Jordan
A Study of Some Generalizations of Proper Mappings
...Show More Authors

Preview PDF
Publication Date
Mon Apr 25 2022
Journal Name
Diversity
Genetic Structure and Diversity of Native Tench (Tinca tinca L. 1758) Populations in Hungary—Establishment of Basic Knowledge Base for a Breeding Program
...Show More Authors

Tench is a cyprinid fish that has undergone human-induced translocations. The natural populations of the species are on the decline due to habitat loss and spawning grounds degradation. The genetic diversity of seven natural populations was investigated to establish the genetic knowledge base for successful conservation efforts and for selective breeding. Twelve microsatellite markers, the sequencing of a 615 bp section of mtDNA (Cytb) and PCR-RFLP analysis of two nuclear markers (Act) and (RpS7) were used to analyze the genetic variation and structure among 175 individuals. All microsatellite loci were found to have moderate levels of polymorphism. The pairwise Fst values between population pairings were moderate; the populations w

... Show More
View Publication
Scopus (7)
Crossref (7)
Scopus Clarivate Crossref
Publication Date
Wed Jan 01 2003
Journal Name
Turkish Journal Of Chemistry
Gas Chr Gas Chromatographic Separ aphic Separation of Phenol Deriv ation of Phenol Derivatives by Schiff- y SchiffBase Liquid Crystalline Stationary Phases
...Show More Authors

The chromatographic behaviour of liquid crystalline compounds benzylidene-p-aminobenzoic acid and 4-(p-methyl benzylidene)-p-aminobenzoic acid as stationary phases for the separation of dimethylphenol isomers was investigated. These isomers were analysed on benzylidene-p-aminobenzoic acid within a nematic range of 169-194 ◦C with a temperature interval of 5 ◦C. Better peak resolution was at a column temperature of 190 ◦C. The analysis was repeated on a 4-(p-methyl benzylidene)-p-aminobenzoic acid column at a nematic temperature of 256 ◦C, which represented the end of the nematic range, and gave the optimum peak resolution. It was found that isomer better separation was obtained at 20% loading for both liquid crystal materials. Other

... Show More
Publication Date
Sat Dec 01 2018
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
" Measuring the competitive performance of the National Insurance Company and some of its branches using the Revealed comparative advantage index RCAI "
...Show More Authors

The research dealt with the subject of measuring the competitive performance of the National Insurance Company and some of its branches (Basra, Ninwa, Kirkuk and Babil), Depending on the Revenue Growth Index at the activity level, and the Revealed Comparative Advantage Index RCAIAt the branch level,To measure the competitiveness of the company And some branches, As the problem of research in the lack of adoption by some companies in the insurance service sector on scientific indicators to measure their competitive performance, The aims of the research is to measure the competitiveness of the National Insurance Company, as well as the competitiveness of its branches according to the scientific method, One of the main Conclusions of the re

... Show More
View Publication
Crossref
Publication Date
Sat Jun 01 2019
Journal Name
Journal Of Economics And Administrative Sciences
Comparison of some methods for estimating the parameters of the binary logistic regression model using the genetic algorithm with practical application
...Show More Authors

Abstract

   Suffering the human because of pressure normal life of exposure to several types of heart disease as a result of due to different factors. Therefore, and in order to find out the case of a death whether or not, are to be modeled using binary logistic regression model

    In this research used, one of the most important models of nonlinear regression models extensive use in the modeling of applications statistical, in terms of heart disease which is the binary logistic regression model. and then estimating the parameters of this model using the statistical estimation methods, another problem will be appears in estimating its parameters, as well as when the numbe

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Mar 06 2016
Journal Name
Baghdad Science Journal
Synthesis and Characterization of Some New Azo Dyes Derivatives Via Chalcone and Study Some of Their Biological Activity
...Show More Authors

This work includes synthesis of new six membered heterocyclic rings with effective amino group using the reaction of benzylideneacetophenone (chalcone) (1) with thiourea or urea in alcoholic basic medium to form: 1,3-thiazen-2-amine (2), and 1,3-oxazin-2-amine (8) respectively. The diazotization reaction was carried out with sodium nitrite in presence of hydrochloric acid to form diazonium salts which suffered coupling reaction with naphthols and phenols in the presence of sodium hydroxide to form colored azo dyes (4-7, and 10-13). o-methylation reaction of compounds (7) and (10) yielded : 1,3-thiazin -2-yl-diazenyl (14), and 1,3-oxazin-2-yl-diazenyl (15) respectively.The new compounds were characterized using vario

... Show More
View Publication Preview PDF
Crossref (2)
Crossref
Publication Date
Tue Jan 01 2013
Journal Name
Al- Mustansiriyah J. Sci.
Synthesis and Characterization of Some Mixed Ligand Complexes of Quinaldic Acid and α-Picoline with Some Metal Salts
...Show More Authors

Some metal ions (Mn+2, Co+2, Ni+2, Cu+2, Zn+2, Cd+2 and Hg+2) complexes of quinaldic acid (QuinH) and α-picoline (α-Pic) have been synthesized and characterized on the basis of their , FTIR, (U.V-Vis) spectroscopy, conductivity measurements, magnetic susceptibility and atomic absorption. From the results obtained the following general formula has suggested for the prepared complexes [M(Quin)2( α-Pic)2].XH2O where M+2 = (Mn, Co, Ni, Cu, Zn, Cd and Hg), X = 2, X = zero for (Co+2 and Hg+2) complexes, (Quin-) = quinaldate ion, (α-Pic) = α-picoline. The results showed that the deprotonated ligand (QuinH) by using (KOH) coordinated to metal ions as bidentate ligand through the oxygen atom of the carboxylate group (-COO-) and the nitrogen ato

... Show More
Publication Date
Wed Apr 10 2019
Journal Name
Iraqi Journal Of Market Research And Consumer Protection
QUALITY SYSTEMS.POSSIBILITY OF IMPLEMENTING IN SOME LOCAL FOOD ESTABLISHMENTS: QUALITY SYSTEMS.POSSIBILITY OF IMPLEMENTING IN SOME LOCAL FOOD ESTABLISHMENTS
...Show More Authors

In order to have an idea about what happens in Iraqi food establishments in relation to implement quality management system ISO 9001, this study was performed to show the actual situation of Iraqi food establishments concerning quality management system (ISO 9001:2015), reasons of implementing, factors that hinder implementing and problems faced high administration for getting establishments certification ISO 9001:2015. The study demonstrated from the questionnaire some difficulties to implement ISO 9001 for both of establishments that implemented the quality system or which in implementing of this international standard. The most important problems during implementing were business culture and costs and the most important proble

... Show More
View Publication Preview PDF
Publication Date
Mon Jul 29 2013
Journal Name
Al- Mustansiriyah J. Sci.
Synthesis and Characterization of Some Mixed Ligand Complexes of Quinaldic Acid and α-Picoline with Some Metal Salts
...Show More Authors

Some metal ions (Mn+2, Co+2, Ni+2, Cu+2, Zn+2, Cd+2 and Hg+2) complexes of quinaldic acid (QuinH) and α-picoline (α-Pic) have been synthesized and characterized on the basis of their , FTIR, (U.V-Vis) spectroscopy, conductivity measurements, magnetic susceptibility and atomic absorption. From the results obtained the following general formula has suggested for the prepared complexes [M(Quin)2( α-Pic)2].XH2O where M+2 = (Mn, Co, Ni, Cu, Zn, Cd and Hg), X = 2, X = zero for (Co+2 and Hg+2) complexes, (Quin-) = quinaldate ion, (α-Pic) = α-picoline. The results showed that the deprotonated ligand (QuinH) by using (KOH) coordinated to metal ions as bidentate ligand through the oxygen atom of the carboxylate group (-COO-) and the nitrogen ato

... Show More
Preview PDF