A polycrystalline CdTe film has been prepared by thermal evaporation technique on glass substrate at substrate temperature 423 K with 1.0 m thicknesses. The film was heated at various annealing temperature under vacuum (Ta =473, 523 and K). Some of physical properties of prepared films such as structural and optical properties were investigated. The patterns of X-ray diffraction analysis showed that the structure of CdTe powder and all films were polycrystalline and consist of a mixture of cubic and hexagonal phases and preferred orientation at (111) direction.
The optical measurements showed that un annealed and annealed CdTe films had direct energy gap (Eg). The Eg increased with increasing Ta. The refractive index and the real part of dielectric constant for films were observed to decrease with increasing Ta, while the extinction and the imaginary part of dielectric were increased. Our result is good candidate for manufacturing optoelectronic device such as solar cells.
In this study two types of extraction solvents were used to extract the undesirable polyaromatics, the first solvent was furfural which was used today in the Iraqi refineries and the second was NMP (N-methyl-2-pyrrolidone).
The studied effecting variables of extraction are extraction temperature ranged from 70 to 110°C and solvent to oil ratio in the range from 1:1 to 4:1.
The results of this investigation show that the viscosity index of mixed-medium lubricating oil fraction increases with increasing extraction temperature and reaches 107.82 for NMP extraction at extraction temperature 110°C and solvent to oil ratio 4:1, while the viscosity index reaches to 101 for furfural extraction at the same extraction temperature and same
Three-dimensional nonlinear thermal numerical simulations are conducted for the friction stir welding (FSW) of AA 7020-T53. Three welding cases with tool (rotational and travel) speeds of 900rpm-40mm/min, 1400rpm-16mm/min and 1400rpm-40mm/in are analyzed. The objective is to study the variation of transient temperature in a friction stir welded plate of 5mm workpiece thickness. Based on the experimental records of transient temperature at several specific locations during the friction stir welding process for the AA 7020-T53, thermal numerical simulation is developed. The numerical results show that the temperature field in the FSW process is symmetrically distributed with respect to the welding line, increasing travel speed decreasing tran
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Permanent deformation (rutting) of asphalt mixtures is one of the major forms of distress. Aggregate gradation is one of the most important factors affecting the permanent deformation of asphalt mixtures. Other variables are also important to understand their effects on the mixture such as temperature, binder content and compaction level. For this purpose 6 different aggregate gradations have been chosen and each one of them has been manufactured / tested with different variables. The results showed that at relatively low temperature there is little effect of aggregate packing on the permanent deformation. However, as the temperature increases the effect of gradation becomes apparent, in that the better the packing the better the resistance
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Objective(s): This study aims to evaluate the hardness of two commercially available cold cured acrylic resin material
(Vertex and PAN) when polymerized at different temperature in comparison to those polymerized by conventional
methods in air at 23C ± 5C.
Methodology: Eighty specimens, forty from cold cured acrylic (Vertex Type) and forty from cold cured acrylic (PAN
type) were prepared, flasking and packing procedure were done according to manufacturer direction and divided
according to processing as follow: 20 specimens (10 from Vertex type and 10 from PAN type) were processed in air for
two hours at 23C ± 5C under press (bench curing) as a control, and 60 specimens (30 from Vertex type and 30 from
PAN type) wer
Friction stir welding (FSW) process is an emerging solid state joining process in which the material that is being welded does not melt. This process uses a nonconsumable tool to generate frictional heat in the abutting surfaces. The welding parameters such as tool rotational speed, welding speed, axial force, etc., and tool pin profile play a major role in deciding the weld quality. In this investigation an attempt
has been made to understand the effect of tool pin profile and rotation diameter on microstructure and mechanical properties in aluminum alloy (2218-T72). Five different tool pin profiles (straight cylindrical, threaded cylindrical, triangular, square, and threaded cylindrical with flat), with three different rotation
d
كانت وسائل الاعلام- التقليدية والحديثة – وستبقى وسيلة مهمة لتدفق المعلومات والتعبير عن المشاعر ووصف الاحداث وتشكيل الرأي العام المحلي والدولي عن مختلف القضايا التي تهم الافراد والمجتمعات وفي مقدمتها قضايا العنف بمستوياته كافة ،والتطرف الديني والارهاب بكل مسمياته وستحاول هذه الدراسة ان تقدم اجابات عن اسئلة محددة تمثل الاطار النظري لدراسات مسحية ترصد النظريات التي ترسم الاطر النظرية الت
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The Role of the Deubiquitylase MYSM1 During Alphavirus Infection Amer Nubgan The members of the genus Alphavirus are positive-sense RNA viruses and it is one of two within the family Togaviridae. Most alphaviruses are predominantly transmitted to susceptible vertebrates by a mosquito vector. Alphavirus disease in humans can be severely debilitating, and depending on the particular viral species, infection may result in encephalitis and possibly life threatening symptoms. Chikungunya virus (CHIKV) is the aetiological agent represents a substantial health burden to affected populations, with clinical symptoms that include severe joint and muscle pain, rashes, and fever, as well as prolonged periods of disability in some patients. In recent
... Show MoreThe media plays an important role in a number of functions performed by them. Press is one of those media which had and still have a clear role in addressing the various issues, topics, and events. Journalism is no longer as expressed by owners of the liberal theory – it seeks to raise the instincts – but it began to excite the minds of readers to meet their needs. At the same time, it does not neglect the search for the truth and work to deliver it to readers. Some have identified a set of tasks carried out by the press including the interest in public affairs, the needs of the community, work to provide happiness, what is beneficial and useful and combat the negative phenomenon and to address the deviations facing society. The comi
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After the political change in Iraq in 2003, Iraq witnessed a stage of social and political development and the strengthening of the legal foundations of the state system, by the approval of the permanent Iraqi constitution of 2005, and stipulating the quota system.
Iraqi women participated in the parliamentary elections from 2005 until 2021, and despite the participation of Iraqi women in all elections, there are challenges that women in Iraq face that prevent their political participation in general and participation in parliament in particular. There are factors behind this, including those related to Iraqi women themselves, including those concerning the political institution and factors related to the nature of society, and it
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The Economist opinion (views) gathered on the great Importance’s of small enterprise on the production sectors at Developed or in developing countries, statistics indicate that these enterprise represent almost 90% of the total enterprises in most economies in the world.
Many of these enterprises have originated in Iraq since the beginning of last century and the question of financing these enterprises remained an issue facing the most of workers in this sector, because of the peculiarty of which are characterized by which as a lack of financial abilities and the difficulty of obtain the sources of financing in Iraq and considered the enterprise as the guarantor of fulfilling Financial obligations. Afte
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