Background: With the increasing demands for adult orthodontics, a growing need arises to bond attachments to porcelain surfaces. Optimal adhesion to porcelain surface should allow orthodontic treatment without bond failure but not jeopardize porcelain integrity after debonding.The present study was carried out to compare the shear bond strength of metal bracket bonded to porcelain surface prepared by two mechanical treatments and by using different etching systems (Hydrofluoric acid 9% and acidulated phosphate fluoride 1.23%). Materials and Methods: The samples were comprised of 60 models (28mm *15mm*28mm) of metal fused to porcelain (feldspathic porcelain). They were divided as the following: group I (control): the porcelain surface left u

An experimental study was performed to estimate the forced convection heat transfer performance and the pressure drop of a single layer graphene (GNPs) based DI-water nanofluid in a circular tube under a laminar flow and a uniform heat flux boundary conditions. The viscosity and thermal conductivity of nanofluid at weight concentrations of (0.1 to 1 wt%) were measured. The effects of the velocity of flow, heat flux and nanoparticle weight concentrations on the  enhancement of the heat transfer are examined. The Nusselt number of the GNPs nanofluid was enhanced as the heat flux and the velocity of flow rate  increased, and the maximum Nusselt number  ratio (Nu nanofluid/ Nu base fluid)   and thermal performance factor

Tetradentate complexes type [M (HL) 2] were prepared from the reaction of 2-hydroxy -1, 2-diphynel-ethanone oxime [H2L] and KOH with ( Mn II, Fe II, Co II, Ni II , Cu II and Hg II ), in methanol with (2:1) metal: ligand ratio. The general formula for Cu II and Mn II complexes are [M (HL) 2 Cl.H2O] K, for Co II [Co (HL) 2. H2O] and [M (HL) 2] for the rest of complexes. All compounds were characterised by spectroscopic methods, I.R, U.V-Vis, H.P.L.C, atomic absorption and conductivity measurements chloride content. From the data of these measurements, the proposed molecular structures for Fe II and Hg II complexes are tetrahedrals, while Mn II and Cu II complexes are octahedrals, Ni II complex adopting square planar structure and the complex

the  civil relation between Iraqis and Egyptian was close , it is clear that is the opening relation between two countries esoecally in trade and demand education , but after mongle occupation  , For the capital of the Abbasid Caliphate, the situation in  Baghdad, had changed in 656 AH/1258 AD,  the Iraqi migration  started security and safety,

    Sought researcher to try to detect the type and size of the problems detected in or discovered or exposed or trying to find solutions to them as teachers and lecturers who are studying the educational, psychological and social articles in college studying these materials, whether the jurisdiction or extra materials, and clarified language definitions and terminology for search terms, indicating the importance of research into the problem of these either for teachers or for their students, and prepared a questionnaire organization questions open to get a clear responses and the Organization of the kind of problems faced by the lecturers and their students who are dealing with the educational, ps

the  civil relation between Iraqis and Egyptian was close , it is clear that is the opening relation between two countries esoecally in trade and demand education , but after mongle occupation  , For the capital of the Abbasid Caliphate, the situation in  Baghdad, had changed in 656 AH/1258 AD,  the Iraqi migration  started security and safety, including scholars and writers, in addition to the presence of entire Iraqi families who immigrated to Egypt and resided there, including the family of Al-Hafiz Al-Iraqi The Ibn al-Kwaik family, the subject of the study, had an important impact on the scientific movement in Egypt.

      MRP is a system intended for the batch manufacturing of discrete parts including assemblies and subassemblies that should be stocked to support future manufacturing needs.  Due to the useful information provided by MRP it has evolved into a Manufacturing Resources Planning, MRP II, a system that ties the basic MRP system to the other functional areas of the company such as marketing, finance, purchasing, etc.  The objective of this research, which was conducted at the State Company for Batteries Manufacturing, is to test the performance of some popular lot-sizing techniques used within MRP II framework. It is hypothesized that the technique which minimizes the total inventory costs does no

The problem of job burnout has become one of the main problems for researchers in social welfare organizations (social protection bodies) - one of the formations of the Ministry of Labor and Social Affairs. Its negative effects increased in light of the COVID-19 pandemic, and in light of the Corona pandemic, the pressures and burdens of workers varied, which resulted in high rates of anxiety, tension, and intellectual and physical exhaustion, and then negatively affected their efficiency in performing work at the individual and organizational level, especially after the increasing tasks of these Bodies in carrying out their role in achieving the general goals and objectives as being The general goals are that they are responsible for provid

This research has taken to the knowledge of the scope of  applying the international specification of (ISO 10015) which is regarded to training by the Iraqi ministry of municipalities and public works ,in order to determine its training quality .By using the checklist made based upon the items of the specification ,after translating the English copy into Arabic ,which takes the indications of training depending on qualitative bases. The results of the analysis emphasized that occurred total average by comparison the evaluation of the training activity in the mentioned ministry with the international specification in all of its main items, which was (%55) ,and totally documented ,which finally refer to the existence of great