Background: In dentistry, dentist takes the advantages of soft lining materials due to the viscoelastic properties. The major problem is the adhesion of the soft liner with the denture base material. Materials and Methods: Heat cured of high impact acrylic resin specimens prepared with dimensions 75x13x13mm for shear bond strength test, soft lining material (Refit and Mollosil) with a 3-mm thickness and used to join each two acrylic blocks. Also four specimens with the same previous dimensions utilized for chemical and physical surface analysis. The specimens grouped as control (without plasma) and experiment (with oxygen plasma) treated high impact acrylic specimens. Results: Plasma treatment increased the shear bond strength for both Refit and Mollosil soft lining material after immersion in distilled water for 30 days as compared with the control group, also there was decrease in shear bond strength for both Refit and Mollosil soft lining material of the experimental group after immersion in denture cleanser for 30 days as compared with the control (without plasma treated) group. AFM analysis revealed that oxygen plasma treatment led to formation of (pits and protuberances) that increase the surface area and increase the shear bond between soft liners and high impact acrylic denture base. Conclusions: Oxygen plasma surface treatment was an effective method for increasing adhesion by physical topographic surface (due to the plasma etching process which in turn led to removal of some material from the surface and this led to increase the bond strength).
Critical buckling and natural frequencies behavior of laminated composite thin plates subjected to in-plane uniform load is obtained using classical laminated plate theory (CLPT). Analytical investigation is presented using Ritz- method for eigenvalue problems of buckling load solutions for laminated symmetric and anti-symmetric, angle and cross ply composite plate with different elastic supports along its edges. Equation of motion of the plate was derived using principle of virtual work and solved using modified Fourier displacement function that satisfies general edge conditions. Various numerical investigation were studied to exhibit a convergence and accuracy of the present solution for considering some design parameters such as edge
... Show MoreThis paper presents a grey model GM(1,1) of the first rank and a variable one and is the basis of the grey system theory , This research dealt properties of grey model and a set of methods to estimate parameters of the grey model GM(1,1) is the least square Method (LS) , weighted least square method (WLS), total least square method (TLS) and gradient descent method (DS). These methods were compared based on two types of standards: Mean square error (MSE), mean absolute percentage error (MAPE), and after comparison using simulation the best method was applied to real data represented by the rate of consumption of the two types of oils a Heavy fuel (HFO) and diesel fuel (D.O) and has been applied several tests to
... Show MoreThe main aim of this work is to investigate the existence and approximate controllability of mild solutions of impulsive fractional nonlinear control system with a nonsingular kernel in infinite dimensional space. Firstly, we set sufficient conditions to demonstrate the existence and uniqueness of the mild solution of the control system using the Banach fixed point theorem. Further, we prove the approximate controllability of the control system using the sequence method.
The present work involved preparation of new substituted and unsubstituted and poly imides (1-17) using reaction of acryloyl chloride with different amides (aliphatic ,aromatic) in the presence of a suitable solvent and amount tri ethyl amine (Et3N) with heating – the structure confirmation of all polymers were proved using FT-IR,1H-NMR,C13NMR and UV spectroscopy ,thermal analysis (TG) for some polymers confirmed their thermal stabilities . Other physical properties including softening and melting points, PH and solubility of the polymers were also measured
In this paper a stirred-bed performed of the copper catalyzed synthesis of ethylchlorosilanes from silicon and ethyl chloride was described. A Si-catalyst mixture prepared by reaction of CuCl and Si was employed. The compositions of products were mainly ethyltrichlorosilane, diethyldichlorosilane, and ethyldichlorosilane and mainly depended on the extent of Cu in the mixture and the reaction temperature. A promoting effect on the extent of adsorption was observed on the addition of certain additives. The kinetic data revealed the direct depended of the reaction rate on C2H5Cl pressure.
It must be emphasized that media is amongst human studies fusing older and more recent sciences together, and that its disclosures are the physics of the new communication. Michio Kaku, a theoretical physicist, in his book “ Visions”, confirms this fact when he says :” As a research physicist, I believe that physicists have been particularly successful at predicting the broad outlines of the future .Professionally, I work in one of the most fundamental areas of physics, the quest to complete Einstein's dream of a "theory of everything." As a result, I am constantly reminded of the ways in which quantum physics touches many of the key discoveries that shaped the twentieth century. “ He then got to the fact that the physical disclo
... Show MoreThis study attempts to test the interactive role played by organizational agility in enhancing the effect of organizational anomie on the behavior of planned human resources. The study of organizational anomie has increased because of the moral and legal pressures facing the organization by the external environment within its framework. To adapt to all external developments faced by these organizations, the behavior of human resources planned reflects the ability of individuals to control their behavior in different situations and situations that face them in the work.
The problem of the research indicates that there is a clear lack of understanding of what is meant by the variables studied in the sample
... Show MoreIn this paper, inelastic longitudinal electron scattering form factors C2 and C4
transitions have been studied in Ti 48,50
and Cr 52,54
nuclei with the aid of shell
model calculations. The core polarization transition density was evaluated by
adopting the shape of Tassie model togther with the derived form of the ground state
two-body charge density distributions (2BCDD's). The following transitions have
been investigated; 0 2 2 2 1 1
and 0 2 4 2 1 1
of Ti 48 , 0 3 2 3 1 1
and
0 3 4 3 1 1
of Ti 50 , 0 2 2 2 1 1
and 0 2 4 2 1 1
of Cr 52 and
0 3 2 3 1 1
and 0 3 4 3 1 1
of Cr 54 nuclei. It is fou
This research reviews the aesthetic variables that were founded according to (theatrical rehearsal) as one of the most important pillars on which the theatrical process is based, because of its necessity in developing theatrical art on several levels that helped the theatrical director in organizing his work, and this became clear through the research chapters represented in the first chapter (methodological framework) and the second chapter, which consisted of the first topic (the duality of watching / rehearsal) and the second topic (the applications of theatrical rehearsal in theatrical experiences), all the way to the third chapter (research procedures), which included the analysis of theatrical rehearsals (sharing on life), and the
... Show More