This paper describes a new finishing process using magnetic abrasives were newly made to finish effectively brass plate that is very difficult to be polished by the conventional machining processes. Taguchi experimental design method was adopted for evaluating the effect of the process parameters on the improvement of the surface roughness and hardness by the magnetic abrasive polishing. The process parameters are: the applied current to the inductor, the working gap between the workpiece and the inductor, the rotational speed and the volume of powder. The analysis of variance(ANOVA) was analyzed using statistical software to identify the optimal conditions for better surface roughness and hardness. Regressions models based on statistical mathematical approach by using the MINITAB-statistical software for both surface roughness and hardness were obtained. Experimental results indicated that rotational speed is the most significant parameters on change in surface roughness(ΔRa), and for change in surface hardness (ΔHa), volume of powder is the significant one. As a result, it was seen that the magnetic abrasive polishing was very useful for finishing the brass alloy plate.
New twin compounds having four-, five-, and seven- membered heterocyclic rings were synthesized via Schiff bases (1a,b) which were obtained by the condensation of o-tolidine with two moles of 4- N,N-dimethyl benzaldehyde or 4- chloro benzaldehyde. The reaction of these Schiff bases with two moles of phenyl isothiocyanate, phenyl isocyanate or naphthyl isocyanate as in scheme(1) led to the formation of bis -1,3- diazetidin- 2- thion and bis -1,3- diazetidin -2-one derivatives (2-4 a,b). While in scheme (2) bis imidazolidin-4-one (5a,b) ,bistetrazole (6a,b) and bis thiazolidin-4-one (7a,b) derivatives were produced by reacting the mentioned Schiff bases(1a,b)with two moles of glycine, sodium azide or thioglycolic acid, respectively. The new b
... Show MoreThe ability of A.hydrophila isolates (63 isolates) to form biofilm, was studied and the results showed that fifty six isolates (88.8%) gave positive results in Congo red agar, while 51 isolates ( 80.7%) gave positive results in Christensen method, sixty isolates( 95.2%) produced biofilm on Polystyrene microtiter plates. Results revealed that all drinking water isolates produced biofilm (18 isolates )and 42 raw water isolates produced biofilm (depending on Polystyrene microtiter plates test). The more two efficient isolates(one isolated from drinking water DW, and other isolated from raw watervRW) which produced biofilm was chosen to study the effect of different values of temperature and disinfectants on the ability of A.hydrophila to ad
... Show Morethe traumatic memory of their ancestors. The novel navigates sites of trauma, memory, and blues music while resisting the bourgeoisie-capitalist relationships that permeated not only white society but also African American communities. Jones’s novel presents the plight of an African American woman, Ursa, caught between the memory of her enslaved foremothers and her life in an emancipated world. The physical and spiritual exploitation of African American women who bear witness to the history of slavery in Corregidora materializes black women’s individuality. This article is framed by trauma studies as well as the Marxists’ concepts of commodification, accumulation, and production. Ursa, one of the Corregidora women, represents
... Show MoreBeing a doctoral student is not easy because it presupposes having a number of technical skills, among which digital skills, defined by the European Commission (2006) as "the safe and critical use of the technologies of the society of the information". and the variety of digital use in the personal and professional context, allows us to ask the question that any doctoral student should master and acquire in terms of digital skills? And on what basis can we define these skills?
In this work we expect to develop a baseline of digital skills, is a document that includes the set of essential digital skills that represents a fundamental tool for the doctoral student who can in no way bypass it. And for this, we conducted interviews with ab
2,2'-(1-(3,4-bis(carboxydichloromethoxy)-5-oxo-2,5-dihydrofuran-2-yl)ethane-1,2-diyl)bis(oxy)bis(2,2-dichloroacetic acid) a derivative of L-ascorbic acid was prepared by reaction of L-ascorbic acid with trichloroacetic acid (1:4) ratio, in the presence of potassium hydroxide. A series of new metal complexes of this ligand were prepared by a reaction with the chlorides of Cd(II), Co(II), Ni(II), Cu(II) and Zn(II). The new ligand and its complexes were identified by C.H.N., IR, UV-visible spectra, Thermogravimetric analysis (TGA), as well as 1H, 13C-NMR and Mass spectra for ligand L. The complexes were also identified by molar conductance, atomic absorption, magnetic susceptibility and X-ray diffraction for Cu (II) complex. FT-IR spectra
... Show MoreThe new bidentate Schiff base ligand namely [(E)-N1-(4-methoxy benzylidene) benzene-1, 2-diamine] was prepared from condensation of 4-Methoxy benzaldehyde with O-Phenylene diamine at 1:1 molar ratio in ethanol as a solvent in presence of drops of 48% HBr. The structure of ligand (L) was characterized by, FT-IR, U.V-Vis., 1H-, 13C- NMR spectrophotometer, melting point and elemental microanalysis C.H.N. Metal complexes of the ligand (L) in general molecular formula [M(L)3], where M= Mn(II), Co(II), Ni(II),Cu(II) and Hg(II); L=(C14H14N2O) in ratio (1:3)(Metal:Ligand) were synthesized and characterized by Atomic absorption, FT- IR, U.V-Vis. spectra, molar conductivity, chloride content, melting point and magnetic susceptibility from the above d
... Show MoreDiabetes mellitus type II is a disorder of metabolism and complex diseases affected by genetic environmental factors and associated with inflammation. The symptoms of type II diabetes develop gradually, which are associated with increased blood concentration of marker of the endothelial inflammatory factors. The expression of adhesion molecules, including E-selectin, intracellular adhesion molecule-1(ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) on the surface of vascular endothelial cells to help leukocyte stick to other surrounding tissues. Many researchers have made attempts to determine the significance of particular ABO phenotype for the susceptibility to diseases. Many reports show a strong association with the ABO blood grou
... Show MoreThe levels of shooting in basketball not very good appears un healthy phenomenon for age stages especially youth players on Iraq and therefore there is lower level in skills especially shooting that seems the players represent their players not good levels which cause difficult in choosing players for youth national team. The research sample were youth teams in Baghdad for season 2012-2013 their birth 1996 and the number teams (7) and after getting results and treat it statically the important ones were : there is a large number of failure attempts on success ones in basic shooting in basketball for youth teams in Baghdad teams (2012-2013) season and basic shooting have effective participation (positive relation) in youth teams ranking in B
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