In this study multi objective optimization is utilized to optimize a turning operation to reveal the appropriate level of process features. The goal of this work is to evaluate the optimal combination of cutting parameters like feed, spindle speed, inclination angle and workpiece material to have a best surface quality Taguchi technique L9 mixed orthogonal array, has been adopted to optimize the roughness of surface. Three rods of length around (200 mm) for the three metals are used for this work. Each rod is divided into three parts with 50 mm length. For brass the optimum parametric mix for minimum Ra is A1, B1 and C3, i.e., at tool inclination angle (5), feedrate of 0.01, spindle speed of 1200 rpm. For copper the optimal parameters combination for best Ra is A1, B1 and C3, i.e., at tool inclination angle (5), feedrate of 0.01, spindle speed of 1200 rpm. For bronze the optimum parameters mix for minimum Ra is A1, B1and C3, i.e., at tool inclination angle (5), feedrate of 0.01, spindle speed of 1200 rpm.
This study expands the state of the art in studies that assess torsional retrofit of reinforced concrete (RC) multi-cell box girders with carbon fiber reinforced polymer (CFRP) strips. The torsional behavior of non-damaged and pre-damaged RC multi-cell box girder specimens externally retrofitted by CFRP strips was investigated through a series of laboratory experiments. It was found that retrofitting the pre-damaged specimens with CFRP strips increased the ultimate torsional capacity by more than 50% as compared to the un-damaged specimens subjected to equivalent retrofitting. This indicated that the retrofit has been less effective for the girder specimen that did not develop distortion beforehand as a result of pre-loading. From
... Show MoreIn this study, biodiesel was prepared from chicken fat via a transesterification reaction using Mussel shells as a catalyst. Pretreatment of chicken fat was carried out using non‐catalytic esterification to reduce the free fatty acid content from 36.28 to 0.96 mg KOH/g oil using an ethanol/ fat mole ratio equal to 115:1. In the transesterification reaction, the studied variables were methanol: oil mole ratio in the range of (6:1 ‐ 30:1), catalyst loading in the range of (9‐15) wt%, reaction temperature (55‐75 °C), and reaction time (1‐7) h. The heterogeneous alkaline catalyst was greenly synthesized from waste mussel shells throughout a calcin
Mixed ligand metal complexes of CrIII, FeIII,II, NiII and CuII have been synthesized using 5-chlorosalicylic acid (5-CSA) as a primary ligand and L-Valine (L-Val) as secondary ligand. The metal complexes have been characterized by elemental analysis, electrical conductance, magnetic susceptibility measurements and spectral studies. The electrical conductance studies of the complexes indicate their electrolytic nature. Magnetic susceptibility measurements revealed paramagnetic nature of the all complexes. Bonding
The research aims to know the relation between positive thinking and self academic motivation, trend towards teaching profession. So a sample of (344) male and female student of the morning study of education colleges from the two universities of Baghdad and al Mustansria for the academic year 2012-2013.
So three tools had been used to achieve the procedures of the research which are: the scale of positive thinking constracted by Abdal satar Ibrahim year 2010, the scale of self academicmotivation constracted by (Gottfried) and adapted by Hanan Hussan year 2010, the scale of teaching profession trend constracted by Enayat Zaki year 1974.
And by using the statistical means of person
... Show MoreOne of the most difficult tasks in modern medical societies is the process of identifying a cure for many infectious diseases caused by drug-resistant microbes. Therefore, it has become necessary to discover new compounds that work in this regard. The currently prepared Schiff base, derived from thiazole, has a biological activity against bacteria and biofilms and its activity increases when it is associated with copper, zinc and platinum ions and forms metal complexes. This study highlights the synthesis and evaluation of novel biological compounds as inhibitors of bacterial growth and biofilms. A three newly complexes are resulting from the reaction of a new Schiff base ligand (LC) with metal ions (Zn, Cu, Pt). The new ligand (LC)
... Show MoreThe effectiveness of upward training with weights to develop explosive power, characterized by speed and some functional variables for young volleyball players Many efforts of sports laboratories in various countries have been devoted to laying scientific foundations and rules in caring for the physical, skilled, planning, and psychological preparation of players and creating the conditions and requirements for reaching players to higher standards. The research aims to:1- Preparing an ascending training program with weights to develop explosive strength, which is characterized by speed and some functional variables for volleyball players.2- Identify the effect of the training program with upward training in weights to develop explosive stre
... Show MoreThis investigation reports application of a mesoporous nanomaterial based on dicationic ionic liquid bonded to amorphous silica, namely nano-N,N,N′,N′-tetramethyl-N-(silican-propyl)-N′-sulfo-ethane-1,2-diaminium chloride (nano-[TSPSED][Cl]2), as an extremely effectual and recoverable catalyst for the generation of bis(pyrazolyl)methanes and pyrazolopyranopyrimidines in solvent-free conditions. In both synthetic protocols, the performance of this catalyst was very useful and general and presented attractive features including short reaction times with high yields, reasonable turnover frequency and turnover number values, easy workup, high performance under mild conditions, recoverability and reusability in 5 consecutive runs without lo
... Show MoreThis study reports on natural convection heat transfer in a square enclosure of length (L=20 cm) with a saturated porous medium (solid glass beads) having same fluid (air) at lower horizontal layer and free air fill in the rest of the cavity's space. The experimental work has been performed under the effects of heating from bottom by constant heat flux q=150,300,450,600 W/m2 for four porous layers thickness Hp (2.5,5,7.5,1) cm and three heaters length δ(20,14,7) cm. The top enclosure wall was good insulated and the two side walls were symmetrically cooled at constant temperature. Four layers of porous media with small porosity, Rayleigh number range (60.354 - 241.41) and (Da) 3.025x10-8 has been investigated. The obtained data of temperatu
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