Background: Fluoridated acrylic resin material can present more stable properties when compared with conventional one.The most widely used fluoride –containing substance added to dental resin materials is sodium fluoride (Naf). This study evaluated the effect of Naf in different concentration to the acrylic resin denture base material and its effect on tensile strength ,modules of elasticity with long –term water immersion (after 4 months immersion in de-ionized water) Materials and methods: Eighty specimens from dumbbells shaped metal pattern for tensile strength test were preparedaccording to ISO 527: 1993 plastic –Determination tensile properties ,in dimensions(60mm, 12mm, 3 ± 0.2mm) length, width and depth respectively were allocated to two groups according to water immersion there were 40 specimens before immersion and 40 specimens after water immersion for 4 months in de-ionized water(the de-ionized water was changed every day),these two groups were sub divided in to four groups according to the concentration of Naf,Naf powder were added to monomer of acrylic in concentrations of 1%,2%and 5% Naf .0% Naf(control group) ,then mixing were done with polymer according to manufacture instructions ,the conventional flasking ,packing procedure were used following that (fast cycle). For tensile strength test the measuring was done by Instron machine,the values of modulus of elasticity were obtained from tensile test . Results: Results showed that the addition of sodium fluoride to acrylic resin material werelower the tensile strength and modules of elasticity with highly significant differences p<0.01 when compared to control group regardless the concentration of Naf,But after immersion (for 4 month ) the tensile strength and modules of elasticity increased in comparison to groups before immersion (with highly significance differences p <0.01 ), highly significance differences (p <0.0)were found between groups after and before immersion in all concentrations except for tensile strength between 1%Naf and 2%Naf after immersion there was no significant differences(p>0.05), and for modules of elasticity between control and 1%Naf, 1% Naf and 2%Naf( after immersion ),there was only significant differences between them(p<0.05). Conclusions: Addition of fluoride to acrylic resin material lower the tensile strength and modules of elasticity when compared to control group regardless the concentration of Naf, But after immersion (for 4 months ) the tensile strength and modules of elasticity increased in comparison to groups before immersion (with highly significance differences p <0.01).
The promotion by its means lead a vital and important role at the level of all organizations, whether (industrial or service) in general, and financial markets in particular. The promotion is earns delved to be as one of the main operations which market uses it through various means of financial markets and companies which its shares listed in the aim of (finance or investment), with a view to the implementation and financing of public and private projects the one hand, or with a view to achieving profits through investment of speculative or... For other purposes, on the other hand.Accordingly, we find that the set of public and private goals joint between the financial markets and listed companies respectively, will serve the stra
... Show MoreThe present study has conducted to investigate the effect of hot aqueous extract of seeds and leaves of fenugreek (Trigonella foenum-graecum) on embryonic development in Swiss albino mice morphologically , the results is showed throught dosage pregnant female orally after period 4, 8, 12days at the beginning of pregnancy by doses 100 , 200 , 300 mg/kg of body weight , the results showed normal period of pregnancy 21 days and abortion did not occur when the pregnant mice take the hot aqueous extract of leaves of fenugreek, but the pregnant mice that take the hot aqueous extract of seeds of fenugreek occurred abortion of embryos and showed some histopathological changes in ovaries and uterus such as congestion, hemorrhage, necrosis, odema,
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(2)
The objective of this experiment was to determine the effects of dietary supplementation with different fat sources on blood parameters of Japanese quail (Coturnix coturnix japonica). Eighty four 7-week old laying quail were randomly assigned to 4 treatment groups (21 birds per group) with 3 replicates for each treatment group and fed for three months on a commercial diet supplemented with 3% of either sunflower oil (T1), flax oil (T2), corn oil (T3) or fish oil (T4). The birds received water and feed ad libitum during the experiment. During the last month of experiment blood samples were collected fortnightly from each bird. The first blood samples collection was used to determine fresh blood parameters, while the second blood samples coll
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(15)
The Islamic orthodox caliphs had a great importance in the history of Arabs in
particular, and of Muslims in general.
Some attributed poetry to them. This issue to see whether such an attribution is correct
or not.
This research tried to deal objectively with this poetry .it discussed the topic,
exploring the scholars’ opinions about poetry attributed to the Islamic orthodox
Caliphs, stating their dispute : some of them agreed while others rejected the
attribution.
The research adopted the opinon that had rejected for reasons stated in the
research, of them: the weakness of poetry and its dealing with unimportant things, for
example, the caliph Omar composed verses about a new garment worn by him.
Is it
The aim of the research is to present and discuss the subject of the budgeting estimates and how to activate the role of the Federal board of supreme audit in examining these estimates through reference to Articles 6 and 10 of the Federal board of supreme Law, which did not restrict Federal board of supreme in Preventive control on examination process for planning which is prepared from the government units, as the result of a large amount of government units Provisions and the weakness of estimates in most of its items, which rely on personal assessment and not based on scientific and logical basis of the estimate, which leads to the emergence of a deficit is not true in the general budget and this seems clear in most Iraq
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China's economic policy and its huge capabilities operate according to an expansion strategy, especially in investing foreign projects, as the past ten years have witnessed a major development in the elements of comprehensive strength, especially in the economic field, in 2014 China launched the largest initiative in the world, represented by the Belt and Road Project (BRI), which links nearly 70 countries, through this project, a very important region has emerged, which is (the port of cadres) in Pakistan, as China has headed towards that region and given the highest importance that is in its interest in the first place regardless of the great Pakistani interest, This is consistent with its future aspirations, especially after breaking
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The research aims to identify the extent to which the theatrical and musical arts contribute to diagnosing and treating psychological problems among the residents of children’s villages in Jordan, and the methodologies adopted by the theatrical and musical arts to achieve this. It moves on to prove the theory that theatrical and musical arts have an impact on improving the psychology of the residents of children’s villages in Jordan by reviewing the theories and opinions that address the subject from a scientific point of view proven by experiences and expertise. The research took place in the period between (2019-2020), and the spatial limits came within the (SOS) children's villages in Jordan. The importance of the research is to
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Abstract
This research was to provide a definition of quality, dimensions and concepts, whether traditional or modern concept, as well as review the dimensions of quality in higher education and vision and mission with the overall objectives of the Statistics Department.
After reviewing quality goals and purposes achieved as well as the mechanisms used to achieve them. and use standard Six-Sigma as one of the methodologies used in quality with the historical roots of using this methodology and methods applied and their definitions t
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The study is aimed at social support to the students of the College of Education for women (The research sample) and measuring the quality of life at students of the College of Education for women (The research sample) And to identify the relationship between social support and quality of life of students of the College Education for Women and research sample consisted of 200 students The adoption of the resolution as a tool for data collection and the most important results of the search results that the students of the College Education for Women have social support. In other words, parents and friends are supporting the students. The students have the quality of life any positive meaning to life and that when a person has a quality of
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