A new scheme of plasma-mediated thermal coupling has been implemented which yields the temporal distributions of the thermal flux which reaches the metal surface, from which the spatial and temporal temperature profiles can be calculated. The model has shown that the temperature of evaporating surface is determined by the balance between the absorbed power and the rate of energy loss due to evaporation. When the laser power intensity range is 107 to108 W/cm2 the temperature of vapor could increase beyond the critical temperature of plasma ignition, i.e. plasma will be ignited above the metal surface. The plasma density has been analyzed at different values of vapor temperature and pressure using Boltzmann’s code for calculation of electron distribution function. This analysis has been used to determine the temporal distribution of the net heat flux, which reaches the solid surface. The net heat flux has been proved to vanish at high plasma density. Accordingly the temporal and spatial distributions of temperature profiles within the solid metal have been modeled depending upon the net heat flux which reaches the target surface.
Three different rotational speeds (800, 1000 and 1250 rpm) and traverse speeds of (0.42 mm/sec) at a constant taped pin have been employed to produce the stir zones generated from friction stir processing (FSP) of near eutectic Al- 14 wt.% Si alloy. The processed samples were thoroughly analyzed macroscopically and microscopically. The as-cast microstructure of eutectic (α Al+ Si) and primary Si were fragmented to produce spheroidization of small size of Si and deformed matrix. The stir zones showed an increase in hardness from around 45-50 Hv for as-cast to 40-65 depending on the variables applied. All the processed samples were characterized by advanced and retreated regions with large single piping defects formed m
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The evolution in materials’ technology in the last decades resulted in interesting projects that aimed at preserving the environment and energy and reduce pollution. They have been taken the principles of environmental design as a basis for architectural thought, starting from the early stages of the design process ending in choosing appropriate building materials to achieve sustainable buildings, but these trying are limited in our local environment and there isn’t demanded seriousness. The research problem emerges in the ignorance of the environmental aspect (ecological system) when selecting building materials during design process to achieve sustainable buildings. The aim of this research is revealing the mechanisms of selecting
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Radiological assessment due to existing of natural occurring radioactive materials
(NORM) in South Rumaila oil field was achieved in this study. Different samples
including soil, sludge, scale, oil, and water were collected from different stages of
oil and gas production in Markazia Degassing Station (SDS) in South Rumaila oil
field. Radioactivity of Ra-226, Th-232 and K-40 were measured using gamma
spectrometry system based on HPGe detector with efficiency of 30%. The results
show that some locations within SDS are contaminated with NORM. The activity of
Ra-226, Th-232 and K-40 range between 18.4 to 312.8, 9.4 to 140.8 and 66.4 to
800.8 (Bq/kg) respectively. The places to be more contaminated among the other
p
Experienced organizations in recent years, significant challenges , especially with the spread of economic globalization, making it required to provide new and better through experience , creativity and innovation to achieve the quality and high-quality products of all kinds , in order to achieve the objectives of the study and to answer its questions tested the study in the woolen Industries sector in Baghdad . The study was applied to a sample of 30 people in the senior management and the middle and lower in the company (managers of sections , and managers of people , and managers of the units , and office managers ) and for the processing of data and information used several statistical methods and extracted result
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In this article, the effects of the O2 ratio on the electrical characteristics, including the I-V characteristic curve, Panchen’s curve, and I-P curve, were tested in a sample of O2/Ar gaseous mixture . The sample was produced by plasma-based DC magnetron sputtering with niobium metal as a target material. The inter-electrode spacing value was 4 cm. Plasma diagnosis via the Optical Emission Spectroscopy (OES) method was used to achieve Te and Ne mixture values of 20 %, 30 %, 50%, and 70% in the Ar/O2 system. The results showed that the discharge is operating in the abnormal glow region and the discharge current was decreased by increasing O2 percentage. In addition, the experimenta
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In this research, we obtained nanoparticles (NPs) using a type of microwave (cold plasma) and water extract from Origanum vulgare with the addition of silver nitrate (AgNO3) solution. Silver nanoparticles are characterized by high production techniques. Experimental factors such as morphology, structure, optical properties and active compounds of the nanoparticle extract were studied through specific tests such as morphology, UV spectroscopy, FE-SEM, FT-IR, and Atomic Force Microscopy (AFM). Plants were used in manufacturing the nanoparticles, as plants are well known for their accessibility and applicability in different pathological areas. The current research provides information on the Green Union System of N
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Background: Laparoscopic cholecystectomy (LC) has become the standard treatment for symptomatic cholelithiasis. Bile duct injury and accidental gallbladder perforation with spillage of bile and stone are common complications of LC. This study was carried out to assess the early complications of gallbladder perforation during LC, and identify the risk factor of that perforation.
Objectives: to evaluate the early complications which may occur after the perforation of the gallbladder during laparoscopic cholecystectomy and to determine the risk factors which are associated with the perforation of the gall bladder.
Subjects and methods: A prospective comparative study o
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The latest events in Iraq and notably the fall of Mosul in the summer of 2014 have marked a turning point in The modern history of Iraq. Violent terrorist groups have overrun a vast area comprising of many towns in mid and northern Iraq causing many casualties and mass migration. Despite Iraq’s long history of pain and suffering the events of the second half of the year 2014 have been the most violent ever witnessed. From this point of view the researcher has tried to identify specifically in this time and place the effect these events have had on the Iraqi artist and to understand how the Iraqi artists depicted this violence in their works of art. The research comprises four parts; the first looked at the language used and the and pro
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Cardiovascular disease (CVD) is a class of diseases that involve the blood vessels or heart. Chlamydia pneumoniae has been considered as the most reasonable; also, it is able to increase and persevere inside vascular cells and to make the chronic inflammation in atherosclerosis. In this study, blood samples were subjected for molecular detection of Chlamydia pneumoniae by using conventional polymerase chain reaction (PCR) depending on 16S rRNA. Seventy patients who suffer from cardiovascular diseases (angina, myocardial infarction and atherosclerosis) aged between 33-86
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