The effect of the magnetic abrasive finishing (MAF) method on the temperature rise (TR), and material removal rate (MRR) has been investigated in this paper. Sixteen runs were to determine the optimum temperature in the contact area (between the abrasive powder and surface of workpiece) and the MRR according to Taguchi orthogonal array (OA). Four variable technological parameters (cutting speed, finishing time, working gap, and the current in the inductor) with four levels for each parameter were used, the matrix is known as a L16 (44) OA. The signal to noise ratio (S/N) ratio and analysis of the variance (ANOVA) were utilized to analyze the results using (MINITAB17) to find the optimum condition and identify the significant parameters affecting on the TR., and MRR of the steel 304. IR camera was used to measure the experimental temperature. The results showed that the optimum temperature in contact area of workpiece is 70.7 °C.
The corrosion behavior of low carbon steel in washing water of crude oil solution has been studied potentiostatically at five temperatures in the range (30–70)°C .The corrosion potential shifted to more negative values with increasing temperature and the corrosion current density increased with increasing temperature. Folic acid had on inhibiting effect on the corrosion of low carbon steel in washing water at a concentration (5× 10-4-- 5× 10-3 ) mol/dm3 over the temperature range (30–70)°C. Values of the protection efficiency were calculated from the corrosion current density .From the general results for this study, it can be seen that thermodynamic and kinetic function were also calculated (?G, ?S, ?H and Ea )
... Show MoreBackground: Pain and the usage of local anesthetic agents are still real problem in pediatric dentistry, for these reasons, the use of minimal invasive dentistry (MID) in regard to the patient comfort is important especially for children, anxious and uncooperative patients. Chemomechanical caries removal (CMCR) methods involve the selective removal of the carious dentine hence it avoided the painful removal of the sound dentine and the anxiety resulted due to the vibration of the hand piece which is also decreased thus it appears to be more acceptable and comfortable to the patient. Aims of this study: This study was conducted among group of children to assess and compare the anxiety rating scale (during and after treatment) between the
... Show MoreJurisprudential rulings were not once restricted to anyone. Even if some prominent imams were famous in one science, this does not mean that some of them were not very knowledgeable and well versed in another science, but he did not know much about it, given his fame in the first science in which he emerged. It prevailed over him until he became known only through him, and there are a large number of these people, and among them is our imam, the great critic Yahya bin Ma’in, may God be pleased with him. Many people, and even scholars, know about him except that he is the only imam in jarh and ta’deel, and on his words and the words of his strike are relied upon. In terms of the authenticity and weakness of the hadith, he is in this f
... Show MoreThe research aims to define the main and subsidiary criteria for evaluating the industrial market sectors and proposing a model for arranging these criteria according to priority and knowing the highest criteria in terms of relative importance in the General Company for Automobile Trade and Machinery, and for the purpose of establishing this model, experiences in the concerned company were approved, and this study proposes a multi-criteria decision model According to the FEAHP, the expanded fuzzy hierarchical analysis method enables the commercial company to develop clear strategic policies on which the company’s management system depends on determining criteria for evaluating and selecting market sectors and making appropriate
... Show MoreS a mples of compact magnesia and alumina were evaporated
using CO2-laser .The
Processed powders were characterized by electron microscopy
and both scanning and transmission electron microscope. The results
indicated that the particle size for both powders have reduced largely
to 0.003 nm and 0.07 nm for MgO and Al2O3, with increasing in
shape sphericity.
يهدف هذا البحث الى تصميم قائمة بمؤشرات القيم العلمية والاخلاقية التي ينبغي توافرها في محتوى كتاب الحاسوب للصف الثاني المتوسط، وتحليل محتوى الكتاب المذكور آنفاً وفقاً لها، وذلك عن طريق الإجابة عن السؤال الآتي: ما نسبة توافر القيم العلمية والأخلاقية في محتوى كتاب الحاسوب المُعد لطلبة الصف الثاني المتوسط الصادر من وزارة التربية العراقية/ المديرية العامة للمناهج في العام الدراسي ( 2017-2018) م؟ ولتحقيق هدفا البحث أ
... Show Moreالسمخص يهجف البحث الحالي التعخف الى: -1 اعجاد مدتهى مقياس لمقيم العمسية . -2 ما العلاقة بين القييم العمسيية لبمبية قديم الايسيياك ييي لميية التخليية لمعميه الريخية/ ابين الهيي م جامعية – بغجاد. لتحقيق أهجاف البحث استخج الباحث السشهج الهصييي بدي م ملاتستيط لع يعية أهيجاف الج ا رسية لقيا الباحيث ب شياك مقيياس القييم العمسيية ايه مين 40 ( يقيخب بسقيياس لي ي ا خا الخساسيي الاييقد الاييق بذيجبد محايجد لا الايقد لا الاي
... Show MoreThe present investigation is concerned for the purification of impure zinc oxide (80-85 wt %) by using petroleum coke
(carbon content is 76 wt %) as reducing agent for the impure zinc oxide to provide pure zinc vapor, which will be
oxidized later by air to the pure zinc oxide.
The operating conditions of the reaction were studied in detail which are, reaction time within the range (10 to 30 min),
reaction temperature (900 to 1100 oC), air flow rate (0.2 to 1 l/min) and weight percentage of the reducing agent
(petroleum coke) in the feed (14 to 30 wt %).
The best operating conditions were (30 min) for the reaction time, (1100 oC) for the reaction temperature, (1 l/min) for
the air flow rate, and (30 wt %) of reducing