Engineering and Technology Journal 

About: Engineering and Technology Journal is an academic journal published by Everant Journals. The journal publishes majorly in the area(s): Computer science & Engineering. It has an ISSN identifier of 2456-3358. It is also open access. Over the lifetime, 2468 publications have been published receiving 5647 citations.

Removal of Heavy Metals Using Chemicals Precipitation

Abstract: The single component and multi-component hydroxide pr cipitation and adsorption were studied for different heavy metals namely Iron (III), Chromium (III), Copper (II), Lead (II), Nickel (II), and Cad mium (II) from aqueous solutions. By using the jar tester Magnesia (MgO) was used as a precipitator at different doses and compared with other chemicals like lime ( CaO) and caustic soda (NaOH). The treatment involves the addition of eith r magnesia or lime-water suspensions (combined with cationic polyelectrolyte , CPE) in various doses, 1.0 – 5.0 g/l for the metal samples to study the effect o f varying doses on the treatment efficiency. The results show that the percent remov al f metal ions increases to about 99 % with increasing the MgO dose to some lim its. The optimum values of MgO doses were found to be 1.5-3.0 g/l. The pH valu e ranges are 9.5 to 10 with MgO precipitant and pH of 11.5 to 12 with CaO preci pitant. In the jar experiment the rotation speed, N, 180-200 rpm, (G of 460-480 s ) of mixing for two minutes was the most favorable speed of rapid mixing and th e slow mixing speed of 15-30 rpm, G of (14-35 s ), for twenty minutes gave the best results.At the best operating conditions of the pilot plant, the removal efficien cy of metal ions was more than 97% at doses of MgO (1.0-4.0 g/l).

A Finite Element Analysis of Orthogonal Machining Using Different Tool Edge Geometries

Abstract: This paper summarizes the effects of edge preparation of the cutting tool in orthogonal cutting on the following variables: stress distributions at the tool rake face, cutting forces and tool-chip contact length. The Finite Element Method (FEM) is selected using the ANSYS /V4.5 code. Six models of cutting tools have been suggested having edge radii of (0.01, 0.05, 0.1, 0.15, 0.2, and 0.25) mm. The results obtained provide a fundamental understanding of the process mechanics for cutting with realistic cutting tool edge radius in order to assist in the optimization of tool edge design. The results show that the optimum edge radius from the six simulated models is (0.05) mm; this edge radius gives minimum value of effective stress. The results show also that the optimum edge radius that shows minimum tangential cutting and feed forces is (0.01) mm. The results investigated that the tool-chip contact length is increased, until reaching maximum value of (2.4) mm at (r=0.15mm), and minimum value of (0.75) mm at (r=0.01mm). The maximum relative difference between simulated results of this work and other previous paper results is (2% - 17%) for the tool effective stresses, (5%) for the tangential force, and (11%) for the feed force.

Mechanical Properties of High-Strength Fiber Reinforced Concrete

Abstract: Experimental results of this work in addition to a wide range of data from previous work were analyzed to study the mechanical properties and strength of high-strength concrete with and without fibers. Different types of steel fibers (straight, hooked, duoform, crimped) with a volume fraction ranging from 0 to 2 percent were studied. The concrete compressive strength ranged from 41 to 115 MPa. The influence of fiber on the compressive strength, axial strain, modulus of elasticity, Poisson's ratio, modulus of rupture, and splitting tensile strength, were studied. In addition to that, size effect of control specimens on high-strength fiber reinforced concrete materials, was observed. The main conclusion indicates that high-strength concrete (HSC) properties, especially with fibers are significantly different from normal-strength concrete (NSC).

The Effect of Using Glass Powder Filler on Hot Asphalt Concrete Mixtures Properties

Abstract: The early use of asphalt for road and street constr uction began in the late 1800s, and grew rapidly with the emerging auto mobile industry. Since that time, asphalt technology has made strides such that today the equipment, techniques and materials used to build asphalt pave ment structures are highly sophisticated. Waste glass has been used in highway construction a s an aggregate substitute in hot mix asphalt paving. Many countrie s have recently incorporated glass into their roadway specification s, which had encouraged greater use of the material. While the use of waste glass as filler in hot mix asphalt is still not widely experimented. In this research glass powder is proposed as an alt ernative to traditional lime stone powder (Gubraa) and ordinary Portland cement fillers in hot asphalt mixtures. Where, the effect of using waste glass powder as mi neral filler on Marshall Properties of hot asphalt concrete mixtures is investigated. N ine mixtures with three types of fillers (lime stone powder, ordinary Portland cemen t and glass powder) and three filler contents (4%, 7% and 10% by weight of total aggregate) are investigated. The main outcome of this research is the possibilit y of using glass powder as filler in hot asphalt concrete mixtures. The optimu m glass powder content is 7%. Where it is found that using of glass powder as fil ler with such replacement leading to produce asphalt mixture with higher stability (% of increase up to 13%), lower flow (% of decrease up to 39%) and lower density (% of decrease up to 10%) comparing to corresponding ordinary Portland cement or lime stone powder mixtures.

The Effect of Cutting Tool Vibration on Surface Roughness of Workpiece in Dry Turning Operation

Abstract: This study is to find a correlation between surface roughness and cutting tool vibration in turning. The ranges of process cutting parameters in the present study are limited: cutting speed (34, 70, 130 m/min), depth of cut (0.1, 0.2mm), feed rate (0.07, 0.13, 0.17mm/rev) and tool overhanging (25, 30, 35, 40mm). The data are generated by lathe dry turning of medium carbon steel samples at different levels of the mentioned above parameters. Dry cutting tests (without using cutting fluid) are conducted to simulate a good turning, the dry turning provided a clean environment to obtain undisturbed clear cutting vibration, which results in more accurate and clear correlation between cutting vibrations and roughness. The analysis of variance reveale in this study is that the best surface roughness condition is achieved at a low (feed rate less and equal 0.13mm/rev), and with smaller tool overhang less and equal 30mm). The results also show that the cutting speed has small effect on surface roughness than feed rate and tool overhang. The depth of cut has not a significant effect on surface roughness in this study. Above results can be obtained when there is no built up edge and no damage of the tool tip. Finally experimental results have shown good correlation between the cutting tool vibration and surface roughness which can be used to control the finish surface of the workpieces during the mass production.