Engineering and Technology Journal

Quintessential characteristics of sawdust were investigated in this study as well as to to investigate the ability of reed as a Production of gases via gasification technique by using special gasifier made for this purpose. The physical properties of solid waste results showed that sawdust were suitable for using in production of syngas due to its high volatile matter and cellulose content and low moisture content. The CHNS analysis results showed that high content of hydrogen for sawdust has generated higher amount of syngas heat value, while gravimetric analysis results showed that high cellulose and hemicellulose content gave higher concentration of hydrogen gas. The percentage of production gases was 15.6%, 10.2%, 7.81% and 1.69% for carbon monoxide, carbon dioxide, hydrogen and methane respectively. The effect of operation time on composition of syngas was investigated to generate good quality gas from different types of solid waste. The quality of syngas was started decreasing after about 30 min of gasifier operation. Therefore, each full capacity run should be limited to only 30 min until refeeding is required.

This paper investigated the effect of incorporating two types of micro particles micro CaCO3 and micro SiO2 on mechanical properties and durability of concrete. Micro materials were added in four different dosages of 1%, 2%, 3% and 4% by weight as partial replacement of cement in concrete mixture. Mechanical properties of hardened concrete (compressive strength, flexural strength and split tensile strength) have been done after 28 days of water curing. In addition, water absorption test was carrying out for obtaining the durability properties of concrete specimen. Binary combination of micro CaCO3 + micro SiO2 were also studied the combined effect of the micro particles. Micro-structural characteristic of modified concrete was done through the scanning electron microscope. The results showed that incorporation of micro CaCO3 and micro SiO2 particles lead to increase the packing and enhance the mechanical properties and durability of concrete. A significant performance was observed in case of micro silica addition to the concrete in comparing with other micro particles.

Analysis using scanning electron microscope (SEM) at high magnification showed that the microstructure of the nano composites exhibited uniform distribution of SiC particles and less porosity. The experimental results revealed that adding Nano Reinforcement to 7075Al alloy improve the electrical conductivity for the metal matrix composites with 3, 6, 9 wt. % SiC were adopted in this work. The maximum enhancements were observed at 9wt. %SiC of 5200(Ω. m) -1 compared with the metal base of 35 (Ω. m) -1.

Submerged Arc Welding (SAW) process is generally used for industries, such as petroleum storage tanks, pressure vessels, and structural components.
Good mechanical properties of welded joint lead to crack-free strong joints. In this research, included angle, current, welding travel speed and arc voltage were utilized as welding parameters to weld ASTM A516 Grade 60 (low carbon steel). The experiments were carried out according to a design matrix that established by DOE (Version10) with RSM technique. Microhardness of welded samples was measured by a Digital Microhardness Tester, and then RSM technique was used to model and optimize the microhardness based on the welding parameters. The results showed that the including angle and welding current have a great effect on the microhardness. The optimum solution for minimum microhardness was found at 450 Amp welding current, 38 cpm welding speed, 34-volt arc voltage and included angle of 60⁰. The optimum value of microhardness was (186.7 HV). Eventually, the experimental and predicted results of microhardness were found in good agreement with 4.6%. maximum error.

This research aims to investigate the effect of punch profile radius on the drawing force, cup wall thickness, amount of spring back induced in the drawn cup, contact regions between blank and punch, strain distributions over the cup wall and height of drawn cup, in deep drawing operation. In this study, a commercial FEA software package (ANSYS11.0) was employed to model a deep drawing operation. A 3-D model of cylindrical cup of (53.4 mm) outer diameter and (33mm) height from a low carbon steel (1008–AISI) of (0.7mm) sheet thickness has been developed and then the FE simulations results are compared with experimental results. To carry out the experimental work, six types of punches of (52mm) diameter with various punch profile radius of (4, 8, 12, 16, 20, 26 mm), die of (53.75mm) die opening diameter with die profile radius of (4 mm) and blanks of (95 mm) diameter have been manufactured. The results indicate that the strain distributions for all punches chosen are similar in shape, and have the same trends. The length of contact distance between the punch and blank increases as the punch corner radius increases and its value approximately is equal to punch corner radius. Drawing force dose not significantly influence by punch corner radius. Thinning increases as punch profile radius increases, and the greatest thinning occurs with the hemispherical punch of (Rp= 26mm). The cup height and the amount of spring back percentage increases as punch profile radius increases.

The mechanical behavior of coconut shell (CS) particulate epoxy composites was concentrated on keeping in mind the end goal to create designing materials for modern application. Minute of the support with various weight portions (5, 10, 15, 20 and 25) wt%. Epoxy and composite materials were prepared by hand lay-up molding. The physical properties are thermal conductivity while the mechanical properties were hardness, tensile properties, impact properties, and flexural strength. The resulting composites of thermal conductivity 0.1005 W∕ m.c° that is lower than pure epoxy and commonplace materials utilized for home-structures. As for the mechanical properties, composite materials with (Epoxy+25%CS) has the maximum hardness of (76.6) shore D, The ultimate tensile strength of 33.42MPa was obtained from (Epoxy+25%CS), while the elongation at fracture with addition in filler concentration of 1.50 % was obtained from (Epoxy+25%CS) is lower than other composites. The highest impact strength, fracture toughness was 80J∕m2, 12.87 MPa.m-1/2 respectively. Flexural strength & shear stress of the composite materials with addition in reinforcement content at 5wt % &10wt% (39, 40.5)Mpa & (1.95,2.03)Mpa respectively while is other composites.

TiO2NP’s were synthesis by sol-gel method at different calcination temperatures. The prepared TiO2NP’s were characterized by X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and UV-Vis spectrophotometer. The antimicrobial activities of the prepared TiO2NP’s were investigative for two kinds of bacteria, (Gram-negative and Gram-positive bacterium. XRD results shows that the type of the TiO2 structure was anatase (A) at low temperatures, rutile (R) with rise of calcination temperature (Tc) into 800 ᵒC and mixed phases .SEM demonstrated that the size of nanoparticles seems larger and the accumulations appears clearly with raise calcinations temperature. The optical properties measured by the UV-Vis. Spectroscopy to compute the energy band gap for all phases around (3.75- 3.5 eV) for anatase and (3.4eV) for rutile. TiO2 nanoparticles in both phases showed excellent antibacterial activity against two representative bacteria, Pseudomonas aeruginosa and Staphylococcus aurous.

A series of Zinc Oxide Nanoparticles (ZnONPs)-functionalized Multi-Walled Carbon Nanotubes (F-MWCNTs) Nano composites were developed as antibacterial. In this study, chemical oxidation of pristine MWCNTs were carried out with a mixture of strong acids (3H2SO4 98%:1 HNO3 65%).The F-MWCNTs were used as templates to prepare hybrid material like ZnONPs decorated F-MWCNTs. Pristine MWCNTs, F-MWCNTs and (ZnONPs/F-MWCNTs) Nano composites powder were investigated using Fourier Transform Infrared spectroscopy (FTIR) and Scanning Electron Microscopy (SEM). Anti-bacterial activity has been carried out using standard agar dilution (plate count) method against Escherichia coli (E. coli). This study demonstrated that (ZnONPs/F-MWCNTs) Nano composite has a powerful bactericidal effect against Escherichia coli (E. coli) at concentration 0.5 mg/ml after 3 hr, which led to speculation that the combination of ZnONPs and F-MWCNTs altered their toxicity and improved antibacterial property of Nano composite.

The study and simulation of a PI speed controller for small UAV or quadcopter motor is discussed in this research. The motor under consideration is MAXON 2260 215, which is a brushless DC motor that has permanent magnets on the rotating part and the stationary windings are connected so that the back electromotive force is trapezoidal. The motor utilizes a PI controller, which dominate the duty cycle of the PWM pulses applied on the switches of the inverter so that the motor can run at the required speed. A Chopper is used as a power converter and a proportional–integral as speed and current controller. The DC motor, which is being run individually, can be controlled on a wide range of operation up to the rated speed. The simulation is implemented and evaluated using PSIM software program under a wide range of speed, voltage and load torque inputs such as the rated speed and load torque, half the rated load torque and half speed since these tests are vital to test maneuver movement such as roll, pitch, yaw and throttle. The main objectives of this paper are; to understand the process of deriving the model for a propeller motor, to evaluate the stability and accuracy of the control loop for successful aviation, to apply a tuning plan on a closed loop system (PI) and to check the system procedure versus the given technical specifications.

The purpose of this study is designate quenching and tempering heat treatment by using Taguchi technique to determination optimal factors of heat treatment (tempering temperature, percentage of nanoparticles, type of base media, nanoparticles type and tempering time)for increasing ultimate tensile strength, yield strength and ductility properties of medium carbon steel. An (L18) orthogonal array was chosen for the design of experiment. The optimum process parameters were determined by using signal-to-noise ratio (larger is better) criterion. The importance levels of process parameters on tensile properties were obtained by using analysis of variance, which applied with the help of (Minitab18) software. Percentage of volumetric fractions of nanoparticles with three different levels(0.01, 0.03 and 0.08 %) were prepared by dispersing nanoparticles that are (α-Al2O3,TiO2 and CuO) with base fluids (De-ionized water, salt solution and engine oil).Medium carbon steel specimens were suffered to hardening and tempering heat treatment process. The variables of tempering heat treatment were temperatures (400 C˚, 550 C˚) and a soaking times (30, 45 and 60 minutes) respectively. Tensile testing performed on samples using united universal hydraulic machine. The results for ( S/N) ratios showed the order of the factors in terms of the proportion of their effect on ultimate tensile strength, yield strength and ductility properties as follow: Tempering temperature ( 400 C˚) ,Nanoparticles type (TiO2 ),Tempering time (30 min),Type of base media (salt solution, engine oil) and Percentage of nanoparticles ( 0.03%) was the least influence for ultimate strength and yield strength while for the elongation were as follows: Tempering temperature (550 C˚),Tempering time(60min), Nanoparticles type (CuO),Type of base media (deionized water) and last percentage of nanoparticles (0.08%).

This paper presents design controllers by using control strategies and (LMI) in order to attenuate the vibrations of a beam. An Aluminum beam with fixed-fixed configuration was chosen as an application example of (AVC) of structure. Six conditions had been taken for (AVC) of the beam. In each condition the beam was the same, the changes was in the actuator and in the disturbance according to the location and the kind of the force applied. The attenuation in vibrations of this beam is in maximizing the decay rate (increasing the damping) and limiting the amplitude of the Beam. In this study Pzt actuator had be used, this Pzt have some constraints in the maximum voltage that can be applied, so the input signal must be bounded and limited to some value. In the result there are four requirements for (AVC), stability, input peak bound, output peak bound, and maximizing the decay rate. These requirements had been formulated in the form of (LMI). These (LMI) can be solved by using The Method of Centers For Minimizing The Eigen values. Once the problem solved, the response of the system in the time domain and in frequency domain had been plotted with controller and without controller. The percentage of reduction in the settling time for condition one was (75.9%), while for condition four was (94.6%) and for condition five was (88.32%). The settling time for conditions two and three had increased which means these two conditions are not useful for active vibration control

In this work, two robust controllers, which are full state feedback, ????2 and full state feedback ????∞ controllers are proposed for the two wheeledinverted pendulum system. The nonlinear equations for the two wheeled inverted pendulum system are developed using Euler – Lagrange equation. The system parameters changes are considered to show the effectiveness of the proposed robust controllers. These controllers are proposed not only to stabilize the pendulum in upright position but also to drive the position to track a given reference input. The results show that more desirable robustness and time response specifications can be achieved using the proposed controllers. The effectiveness of the proposed controllers is verified experimentally using real two wheeled inverted pendulum system.