The nanocompsite of alumina (Al₂O₃) produced a number of beneficial effects in alloys. There is increasing in resistance of materials to surface related failures , such as the mechanical properties , fatigue and stress corrosion cracking .The experimental results observed that the adding of reinforced  nanomaterials  type Al₂O₃  enhanced the   HB hardness, UTS, 0.2 YS and ductility of 2014 Al/Al₂O₃ nano composites . the analysis of experiments, indicated that The maximum enhancement was observed at 0.4 wt.% Al₂O₃. The ultimate improvement percentage were 15.78% HB hardness, 18.1% (UTS), 12.86% (

A friction stir spot welding (FSSW) process is an emerging solid state joining process in which the material that is being welded does not melt. In this investigation an attempt has been made to understand the effect of tool shoulder diameter on the mechanical properties of the joint. For this purpose four welding tools diameter (10,13, 16 and 19) mm at constant preheating time and plunging time were used to carry
out welding process. Effect of tool diameter on mechanical properties of welded joints was investigated using shear stress test and Microhardness of joint which welded was studied. Based on the stir welding experiments conducted in this study the results show that aluminum alloy (1200) can be welded using (FSSW) process with

Objective This study evaluated the effects of adding titanium oxide (TiO2) nanofillers on the tear strength, tensile strength, elongation percentage, and hardness of room-temperature-vulcanized (RTV) VST50F and high-temperature-vulcanized (HTV) Cosmesil M511 maxillofacial silicone elastomers. Methods Two types of maxillofacial elastomers, VST50F RTV and Cosmesil M511 HTV, were used. Nano-TiO2 powder was applied as a nanofiller. A total of 120 specimens were fabricated, 60 each of VST50F and Cosmesil M511. The specimens of each type of elastomer were divided into three equal groups on which tests were conducted for tear strength, tensile strength, and hardness i.e., 20 specimens were used for each test. Each group of 20 specimens was further

Experimental programs based test results has been used as a means to find out the response of individual elements of structure. In the present study involves investigated behavior of five reinforced concrete deep beams of dimension (length 1200 x height 300 x width150mm) under two points concentrated load with shear span to depth ratio of (1.52), four of these beams with hallow core and
retrofit with carbon fiber reinforced polymer CFRP (with single or double or sides Strips). Two shapes of hallow are investigated (circle and square section) to evaluated the response of beams in case experimental behavior. Test on simply supported beam was performed in the laboratory & loaddeflection, strain of concrete data and crack pattern of

The research included the preparation of cyclic compounds from thiazoles, imidazoles and oxazepines from the reaction of cyclization starting material that acts Schiff bases, which is a raw material in the formation of cyclic compounds from Schiff's(B1) by reaction of 4- aminobenzenesulfonylamide with 4-hydroxyacetophenone which can used to synthesized two lines. The first introducing the preparation of pyrazoles [B4, B5] from ester [B2], which derived to acid hydrazide[B3] with hydrazine hydrate and final pyrazoles obtained by the reaction with diethylmalonate and acetylacetone. The second including prepared the new 1,3-oxazepine1,5-dione derivatives[B6,B7,B8] from adding different anhydrides to the base[B1] as a seven membered ring ; te

This paper demonstrates an experimental and numerical study on the behavior of reinforced concrete (RC) columns with longitudinal steel embedded tubes positioned at the center of the column cross-section. A total of 12 pin-ended square sectional columns of 150 × 150 mm having a total height of 1400 mm were investigated. The considered variables were the steel tube diameters of 29, 58, and 76 mm and the load eccentricity (0, 50, and 150) mm. Accordingly, these columns were divided into three groups (four columns in each group) depending on the load eccentricity (e) to column depth (h) ratio (e/h = 0, 1/3, and 1). For each group, one column was solid (reference), and the other three columns contained steel tubes with hollow rat

The use of composite materials has vastly increased in recent years. Great interest is therefore developed in the damage detection of composites using non- destructive test methods. Several approaches have been applied to obtain information about the existence and location of the faults. This paper used the vibration response of a composite plate to detect and localize delamination defect based on the modal analysis. Experiments are conducted to validate the developed model. A two-dimensional finite element model for multi-layered composites with internal delamination is established. FEM program are built for plates under different boundary conditions. Natural frequencies and modal displacements of the intact and damaged

Herein, the interfacial polymerization method has been used for the synthesis of PPy/NaVO3 composites with different compositions of NaVO3 (10 %, 20 %, 30 %, 40 % and 50 %) as an efficient electrode material for supercapacitors. The successful formation and composition of the as-prepared composites (PV1-PV5) were confirmed by FTIR, XRD, EDX, and SEM analysis. The electrochemical properties were investigated by cyclic voltammetry (CV), galvanometric charge–discharge measurement (GCD), and electrochemical impedance spectroscopy (EIS) in 0.5 M H2SO4 electrolyte. As compared to other, the PV4 composite exhibit excellent specific capacitance of 391 F g−1 at a current density of 0.75 A/g with good cycling stability of ∼59 % after 1000 cycle

This paper presents an application of a Higher Order Shear Deformation Theory (HOST 12) to problem
of free vibration of simply supported symmetric and antisymmetric angle-ply composite laminated plates.
The theoretical model HOST12 presented incorporates laminate deformations which account for the effects
of transverse shear deformation, transverse normal strain/stress and a nonlinear variation of in-plane
displacements with respect to the thickness coordinate – thus modeling the warping of transverse crosssections more accurately and eliminating the need for shear correction coefficients. Solutions are obtained in
closed-form using Navier’s technique by solving the eigenvalue equation. Plates with varying number of

      In this research, a variable stiffness actuator is proposed to enhance the damping of the mechanical vibrating system. The frequency response analysis of the vibrating system is dependant in order to analyze and synthesis this semi-active damping, where the suggested process is using active filter to estimate the present frequency of the vibration system, and this will limit the value of the stiffness of the vibrated system. Two active filter s are needed, low-pass-filter (LPF) to choose the higher stiffness of the actuator at small frequencies as well as more damping and high-pass-filter (HPF) to choose the lower stiffness of the actuator at high frequencies as well as more damping, and so