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.
Background: Noise injury and hearing loss are significant problems in Nigerian community. The hearing loss sustained from noise injury can have disabled personnel and social consequences for the affected persons and their families. This study was carried out to quantify the noise level of over eighty (80) different sources using the sound level meter (GB: 2266204) at different locations in Akure, capital of Ondo State, Nigeria. Standard procedure specified by the manufacturer was strictly followed and the results were statistically analyzed. The range of results obtained were: household products (48.5±0.5 - 105.7±3.2dBA), traffic (60.9±0.6 - 77.5±1.2dBA), market (55.0±0.5 - 68.1±0.7dBA), automobile/ workshop (65.7±0.5 - 105.7
... Show MoreBackground: Many variables determine the destructive capacity of a weapon; missile velocity is an important consideration. Wounding capability of a missile depends on the amount of kinetic energy dissipated in the tissues. A penetrating high velocity missile (usually bullets) transfers a destructive energy called shock wave to the surrounding tissues.
Objective: To detect and estimate tissues damage away from the main track of high velocity missiles in firearm rifled weapons injuries.
Methods: This cross-sectional study is performed in medico-legal institute in Baghdad for (8) month’s duration from (1-1-2010) to (1-9-2010). Full proper autopsy including external and internal examination of the body for all cases was performed, an
IR, MIR, UV – Visible spectra have been studied for Cobalt chloride molecule (CoCl2. 6H2O) compound, In wide range spectra (40000 – 410) cm-1 specially MIR range. Assignment were achieved for the fundamental vibrational bands of (CoCl2 . 6H2O ) to symmetry stretching ?1 (?^+) Anti – symmetry stretching ?3(?^+), these bands are non-degenerate , and the bending band is ?2(?) is doubly degenerate thought they have activity in IR and Raman , which explain the weakness in symmetry of this molecule, the fundamental bands for the molecule are centered at the following wave numbers (615, 685, 795, 1115, 1340, 1375, 1616.35, 2091, 2386, 2410, 3364) cm-1 which are corresponding to wave lengths (16260, 14598, 12578, 8968, 7462, 7272, 6186,
... Show MoreExperimental results for the density of states of hydrogenated amorphous silicon due to Jackson et al near the valence and conduction band edges were analyzed using Levenberg-Marquardt nonlinear fitting method. It is found that the density of states of the valence band and the conduction band can be fitted to a simple power law, with a power index 0.60 near the valence band edge, and 0.55 near the conduction band edge. These results indicate a modest but noticeable deviation from the square root law (power index=0.5) which is found in crystalline semiconductors. Analysis of Jackson et al density of states integral J(E) data over about (1.4 eV) of photon energy range, showed a significant fit to a simple power law with a power index of 2.11
... Show MoreExternal Morphologicalstudy of species DiplacodestrivialesRambure of family :
Libellulidae from suborder Anisoptera of the order Odonata which were collected from
Maisan Governorate 2010.
such study was included : Detailed description of most body parts (Head,
Thorax,Abdomen and their appendages), identification and recognition of species, study male
and female genitalia. The species Diplacodes Triviales Rambure was new record to Iraqi
fauna of Odonata.
Abstract
The mine object for this research is determine the nature of the relation and effect between Human resources management strategic to less the work stress , Human resources management strategic represent a set of procedures and practices to manage the human resources at the organization. the stress of work effect on the performance of the human resources , al rasheed bank select to applied the qustioneer on the 32 person the work on the sebaa branch , using the qustioneer as a tool to collect data that is design according some of the standards and make the validity and stability. to analyses this data by using spss for computation " percentage , mean , standard , deriation
... Show MoreBackground: Long QT syndrome is an important cause of arrhythmic death, and it is characterized by electrocardiographic changes and a prolonged QT interval. Patients may present with sudden cardiac death, recurrent syncope, and palpitation.
Objective: Clinical orientation for the Long QT syndrome and minimizing its misdiagnosis to achieve high diagnostic index.
Patients and Methods: Patients presenting with ventricular arrhythmias, syncope, dizzy spells, and prolonged, non-drug-induced QT interval from 2004 uptil 2019 at Al Nasirya Heart Center , Al Sulaimanya Heart Hospital, and Al Nahrain Teaching Hospital were enrolled in this study. All aptients studied clinically and followed up. Management included beta blocker drug therapy a
Background: Acute idiopathic thrombocytopenic purpura (ITP) is a self – limiting illness, usually occurring after an infectious disease, and it is due to decrease number of circulating platelets manifests as a bleeding tendency, easy bruising (purpura), or extravasations of blood from capillaries into skin and mucous membranes. &n
... Show MoreIn this work, nanostructure porous silicon surface was prepared using electrochemical etching method under different current densities. I have studied the surface morphology and photoluminescence (PL) of three samples prepared at current densities 20, 30 and 40 mA/cm2 at fixed etching time 10 min. The atomic force microscopy (AFM) images of porous silicon showed that the nanocrystalline silicon pillars and voids over the entire surface has irregular and randomly distributed. Photoluminescence study showed that the emission peaks centered at approximately (600 – 612nm) corresponding energies (2.06 – 2.02eV).
While current-voltage characteristics shows, as the current density increase the current flow in the forward bias is decreasi
The current study included interpretations of the three-dimensional seismic survey data of the Najaf-Karbala region, which was recently implemented by the Fifth Amphibious Seismic crew of the Oil Exploration Company for the period from 30/1/2016 to 13/10/2017. The total area planned to be covered by the three-dimensional survey program was about (3340 km ²). The Zubair reflector was picked, interpreted, and tracked within the region. The faults affecting this reflector were captured. The reflector's temporal, velocity, and depth maps showed the presence of structural closure features in the southeast of the region and extensions to the structural noses to the northwest of the study area. The structural maps showed a general ten
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