In this paper, magnesium oxide nanoparticles (MgO NPS) have been prepared and characterized and its concentration effect has been studied on polymers surface (MgO NPS). The results showed that the degradation of poly methyl methacrylate increased when using such metal oxide. The results also showed that the metal oxide increased the degradation of poly methyl methacrylate. X-ray diffraction, scanning electron microscopy, atomic force microscopy were used to study the morphological characteristics and size of nano MgO particles analysis. Films were prepared by mixing the different masses of MgO NPS (0.025, 0.05, 0.1, 0.2 and 0.4) % with a polymer solution ratio (W/V) 7 %. Photo- degradation rate was monitored irradiation’s time by measuring the incident frequency of the index value of the hydroxyl coefficient of growth (IOH) at fixed film thickness and constant concentration. Spectrophotometry (IR, and UV. Visible) techniques were used to determine the change in the intensity of the spectrum bundles.
Statement of the Problem. The use of orthodontic fixed appliances may adversely affect oral health leading to demineralizing lesions and the development of gingival problems. Aims of the Study. The study aimed to coat orthodontic archwires with chlorhexidine hexametaphosphate nanoparticles (CHX-HMP NPs) and to evaluate the elusion of CHX from CHX-HMP NPs. Materials and Methods. A solution of CHX-HMP nanoparticles with an overall concentration of 5 mM for both CHX and HMP was prepared, characterized (using atomic force microscope and Fourier transformation infrared spectroscopy), and used to coat orthodontic stainless steel (SSW) and NiTi archwires (NiTiW). The coated segments were characterized (using scanning electron microscopy
... Show MoreBackground: Nanoparticles are clusters of atoms in a size range from (1-100) nm. Nano dentistry creates amazing useful structures from individual atoms or molecules (nanoparticles), which provides a new alternative and a possibly superior strategy in prevention and treatment of dental caries through management of dental plaque biofilms. The aim of the study was to test the sensitivity of Streptococcus mutans to different concentrations of hydroxyapatite and iron oxide nanoparticles suspension solutions, in comparison to chlorhexidine, and de-ionized water, in vitro. Materials and methods: Agar well technique was applied to test the sensitivity of Streptococcus mutans to different concentrations of hydroxyapatite and iron oxide nanoparticle
... Show MoreInsurance is one of effective high-impact activities in the economic and social aspects of development and that the insurance companies after the creation of stability, balance and support other sectors. The insurance of financial institutions with economic and social importance has an impact on the development and help shoulder the burden of risk and distribution. And measuring Indicators of service and cost her help in evaluating the performance and activity of insurance, and the study of sectors needed by society, institutions and individuals and development of the company. Covering all aspects of life and activity. In this study will focus on the insurance sector in the field of car accidents and so plentiful and their problems and d
... Show MoreThis study discussed the effects of doping with silver (Ag) on the optical and structural properties of
CdO nanoparticles at different concentrations 0, 1, 2, 3, 4, 5 wt% prepared by the precipitation method. The
materials were annealed at 550˚C for 1 h. The structural, topographical, and optical properties were
diagnosed by X-ray diffraction analysis, atomic force instrument, and visible and ultraviolet spectrometers.
The results show that the average diameter of the grains depends on the percentage of added silver to the
material, as the diameter decreased from 88.8 to 59.7 nm, and it was found that the roughness increased from
5.56 to 26.5. When studying the optical properties, it was noted that th
The concept of TQM is based on one of the concepts that combine administrative and innovative methods. The aim of the research is to demonstrate the dimensions of TQM in enhancing the satisfaction of the taxpayers through a survey of a sample of officials in the General Authority for Taxation and 50 officials. In the collection of data and information, and the results were analyzed using the SPSS program to find the most important compounds and factors in he method of analysis.
The research problem was represented by the non-application of the General Authority for Taxation to the entrances and modern practices in the administrative work. The results of some of the complications that accompany the tax accounting process, which af
... Show MoreIncreasing need for day after day to find ways and innovative means of
helping to educate and give children the skills of different kind, has found a
researcher on the subject of hats, six room to give children language skills
through the experience of field reconnaissance conducted on the three
children found that language skills improved, he decided to make these study.
Objectives of the study:
Understand the differences between the experimental group first (the way the
debate) and second (six caps) depending on the test post administration.
to identify the language skills of the second group according to the pre and
post test
Differences between males and females in the second group (Six Hats)
Search T
The research aims at conducting a follow-up evaluation of a number of strategic projects implemented by the Directorate of Public Municipalities, one of the Ministry of Construction, Housing and Municipalities and Public Works. The sample included (35) varied strategic projects implemented in most Iraqi governorates. Buildings, municipal buildings, minarets, massacres, multi-story parking, paving and rehabilitation of streets and residential neighborhoods. The difference between the actual and planned times and costs of these projects was then measured and analyzed. These projects were used as a tool for collecting data and information. The questionnaire included four axes, each representing one of the parties to the project, whi
... Show MoreInvestments in shares represent an essential component of companies’ assets and a source of profit making resources. These investments are linked to the areas of trading and speculation, which is reflected on their market value, which makes accounting for and evaluating these investments require their own accounting standards, and thus several international standards were issued regarding this as well as a statement of their impact on growth Sustainable, as the research problem is to show the impact of measuring investments in shares according to international accounting and financial reporting standards on the sustainable growth of economic units, the research sample and its reflection on audit procedures. In accordance with i
... Show MoreThis investigation was carried out to estimate the antiparasitic potential of chitosan nanoparticles loaded with paromomycin against