In this paper, the performance of an optical modulator based on indium tin oxide is investigated at telecommunication wavelength for different accumulation thickness. The plan of metal-oxide-semiconductor is utilized to change the carrier concentration at indium tin oxide-hafnium oxide interface. An optical mode solver based finite element method has been used to calculate the basic parameters such as the insertion loss and extinction ratio. A typical model is presented for carrier concentration modeling of indium tin oxide. The simulation result shows a peak in insertion loss plot with value of 8. 4 dB/μ m. Also, the variation of ITO and HfO2 thicknesses have been investigated. The results show that by increasing the thicknesses, insertion loss and extinction ratio decrease. Furthermore, the effect of accumulation Layer thickness of indium tin oxide is investigated on modulator performance.

The impact behavior of steel– polyurea bi-Layer panel is studied and the effect of nano clay addition to polyurea is investigated. Experimental and numerical analysis is used. Polymeric and nano polymeric biLayer specimens are fabricated and Simple tension test and drop impact test are carried out. Impactor acceleration for each test is recorded and compared with numerical one. Experimental results show that adding nano clay to polyurea will improve impact energy Absorption and plastic deformation of bi-Layer panel. nano clay with 1% weighting is added to soft part of the polyurea i.e. polyamine. Mechanical mixing and ultrasonic dispersion system is used for good dispersion of nano particles before mixing in polyamine.Experimental results show that elastic modulus is increased about 60% and elongation at break is decreased about 7% with nano clay addition. Also nano clay effects on bi-Layer panel is studied with drop impact test and the results is verified with numerical analysis. It is shown that adding nano clay to polyurea as a reinforcement filler has increased the impact energy Absorption about 3% and has decreased the maximum plastic deformation about 7 %. The experimental results show a good agreement with the numerical ones when compared together.

Aim: The aim of this study was to compare the effects of Ethylen glycol tetra acetic acid (EGTA) and EDTA for their smear Layer removal capability using scanning electron microscopy technique.Material and Methods: A group of 28 single rooted teeth were instrumented to size 60 master file. Four teeth were also kept as control while the remaining teeth were divided into two groups. Group A: in which 12teeth were irrigated with 10 ml of 17% EGTA for 2 minutes? Group B: consisted of 12teeth irrigated with 10 ml of 17% EDTA for 2 minutes. Both groups were then irrigated with 10 ml of 5% Naocl. the control group were just irrigated with 10 ml of 5 % Naocl. All teeth in then the control group were only irrigated with 10 ml of 5% Nacl. Specimeus were then sectioned longitudinally. A scanning electrone microscope was wsed to in vetig ate the intenal surfaces of the canal.Results: EGTA chelated dentin surface more conservatively than EDTA without causing erosion.Conclusion: It seems that EGTA can be used safely to remove smear Layer from the canal surfaces.

The purpose of this paper is to present an analytical model for analyzing the penetration process by aspherical noseshape cylindrical on the kevlar/elastomer and the kevlar/epoxy composites and comparing them with each other using the energy method. To investigate this issue, energy Absorptionequations forlinear andnonlinear materials are analyzed as a criterion for the performance of matrix-reinforced fabric. In this predicted model, the dependence of the ballistic behavior of the first and second Layers of the composites on each other during the impact is considered. In this presented model, the components of energy Absorption include the initial kinetic energy of the projectile, the kinetic energy of the projectile, the kinetic energy of the composite cone ahead of the tip of the projectile, the energies absorbed by primary and secondary yarns, the energies absorbed by the delamination among the Layers and the cracking of the matrix, the energy dissipated by plugging of the Layers is calculated during impact. The results of this study show a positive effect of elastomer use on thermoset matrix in composite. Also, analytical results are validated with the experimental results of previous studies and the perturbation analysis is done to examine the reason for error.

In the present study the effect of change in thickness and material of the middle Layer in fiber metal laminates (FMLs) with squared section on the energy Absorption is investigated. In this work four types of specimens, based on the change in the material of the middle Layer, were produced. In order to fabricate FML samples, Glass-epoxy, Carbon-epoxy, polyurethane foam and aluminum 2024 were utilized as the middle Layer and aluminum 2024 for inner and outer Layers, respectively. The specimens were then subjected to the compression test and their forcedisplacement curves were experimentally obtained. Additionally, the effect of the middle Layer thickness on the energy abortion performance was studied by numerical simulation using Ls-Dyna explicit code. The numerical model was initially validated by experiment. In conclusion, it was found that the maximum and minimum efficiency were determined for the FML specimen made of Carbon-epoxy and foam, respectively. Moreover, by changing the middle Layer thickness, it was numerically demonstrated that the specimen with three Layers of the same thickness yields the best Absorption energy capability.