The investigation of the effect of tempering on thermal analysis of
Al-Ti-Si alloy and its composites with MgO and SiC particles was
performed. Thermal analysis was performed before and after
tempering by DSC scan. Optical microscopy was used to identify the
phases and precipitations that may be formed in base alloy and
composites. X-ray diffraction test indicated that the Al3Ti is the main
phase in Al-Ti-Si alloy in addition to form Al5Ti7Si12 phase. Some
chemical reactions can be occurred between reinforcements and
matrix such as MgO.Al2O3 in Al-Ti/MgO, and Al4C3 and Al(OH)3 in
Al-Ti/SiC composite. X-ray florescence technique is used to
investigate the chemical composition of the fabricated specimens.
Heat treatment (Tempering) changes the microstructure of base alloy
and its composites which was assessed by DSC scan. Generally,
three main peaks appeared in DSC represented by GP zone, S phase
(precipitations) and dissolution of phases or precipitations. After
tempering, composite with SiC particles showed better results than
base alloy and composite with MgO. Since the optical microscopy
revealed reforming the stable phase Al3Ti with evaporation some
gases from composite. DSC analysis showed the stability of
composite with SiC was up to 270oC.
Healthcare professionals routinely use audio signals, generated by the human body, to help diagnose disease or assess its progression. With new technologies, it is now possible to collect human-generated sounds, such as coughing. Audio-based machine learning technologies can be adopted for automatic analysis of collected data. Valuable and rich information can be obtained from the cough signal and extracting effective characteristics from a finite duration time interval that changes as a function of time. This article presents a proposed approach to the detection and diagnosis of COVID-19 through the processing of cough collected from patients suffering from the most common symptoms of this pandemic. The proposed method is based on adopt
... Show MoreThe main objective of the audit is The asset is maintained and operated efficiently and is done through to detect fraud and errors in the financial statements and to verify the accuracy and accuracy of the information contained therein and to give a neutral technical opinion on the basis of that, thus the auditor has a professional responsibility in achieving this goal, and that the effects of issuing a wrong opinion works on The loading of the beneficiaries is significant damage, And therefore the presence of any error or bias of the auditor when taking personal judgments in relation to the determination of the relative importance and the selection of audit samples and determine the adequacy and validity of evidence and implemen
... Show Morethis research paper aims at measuring and analyzing the influence of the stock exchange on the economic development in the Kingdom. This is done through comparing the Gross Domestic Product (GDP) as a changeable factor affiliated with some independent variables in the KSA stock exchange. These variables are (All Share Index {TASI}, Market Value, Trade Volume Index, number of companies and number of shares). The study covers the period from 2003 to 2017 and adapts the measuring method in analyzing this relation using the Multiple Linear Regression (Stepwise) and (SPSS). The study affirmed the validity of the
... Show MoreThe primary aim of this research was to study visual spatial attention and its impact on the accuracy of the diagonal spike in volleyball. A total of 20 volleyball players of Baghdad participated in this study. The sample was homogeneous in terms of height, weight and age of the players. The tests used in the present study were: 1) Visual Spatial Attention Test. 2) Volleyball Spike Test. Based on the findings of the study, the researcher concluded that visual spatial attention has a significant impact on the accuracy of the diagonal spike in volleyball.
The research aims to determine the impact of Human Resources Accounting (HRA) on employee’s performance. The research’s problem was embodied in the lack of interest in HRA, which was reflected on the performance of employees in the Ministry of Education; the research adopted the descriptive-analytical approach, and the research community included the directors of departments and people at the headquarters of the Ministry of Education. The sample size was (224) individuals from the total community of 533. The questionnaire was adopted as the main tool for collecting data and information, as well as the interviews that were conducted by the researcher. In order to analyze t
... Show MoreThe preparatory phase since it corresponds to adolescence are the most important stages of life , where the individual 's personality to take shape at this stage and start asking questions about the same , trying to discover the positive and negative traits hehas in order to form distinctive character and also is being he have Love Poll For everything that goes on around him.
And attention to cognitive motivation is important for students because the student who owns a motive cognitively looking for self - knowledge with conviction, and learning then be meaningful and lasts long. The motive of knowledge are common in which cognitive components does not mean exclusive knowledge on academic books and research in the narrow borders but a
The aim of this project was to study the in vitro effect of antineoplastic drugs (vincristine and vinblastine) on mice spermatozoa. Eighteen adult (age 8-9 weeks) male mice were divided into three groups equally. The animals in each group were slain by cervical dislocation, the testes were removed and two tails of epididymides isolated. Spermatozoa were obtained from the two tails of epididymides by mincing in 500 µl TCM-199.The first group non-treated (unadded) as a control group, second group added 10 µg/ml of vincristine to TCM-199 and the third group added 10 µg/ml of vinblastine to TCM-199. After 10 minutes from added of vincristine and vinblastin measured the following test: spermatozoa activity, percentage dead spermatozoa and mor
... Show MoreIn this article it is proved experimentally that the photon is a particle that has mass and constant wavelength by explaining the effect of refractive index on the wavelength and the natural mass of photon. It is very difficult to measure the mass of photon, a simple and easy process was proposed in this paper to calculate the mass length of photon in vacuum (Y) and in medium (Y*), by measuring the length of laser beam in air (Lair) and in medium (Lmed). A new method was postulated to calculate refractive index by using these relations (n = Y*/Y), and (n = Lmed / Lair) which supposed a new theory of light.
This study was conducted in a laboratory experiment at the University of Baghdad, College of Science, computing Department, 5 km from the center of Baghdad city, in 2021 to evaluate the sorting method for the tomato crop. The experiments were conducted in a factorial experiment under a complete randomized design with three replications and using SAS analysis, artificial neural network, image processing, the study of external characteristics, and physical features; fruit surface area and fruit circumference were 1334.46 cm2,57.53 cm2 and free diseases. The error value was less than zero, while training with outputs recorded the highest value and which was 5. The neural network's performance between the input and the mean square of th
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