An experimental investigation of the variation of argon discharge current with a glow and afterglow time intervals of a square discharge voltage was carried out at low pressure (6-11 mbar). The discharge was created between two circular metal electrodes of diameter (7.5 cm), separated horizontally by a distance (10 cm) at the two ends of a Pyrex cylindrical tube. A composite of two Gaussian functions has been suggested to fit and explain the variation graphs clearly. It is shown that the necessary times of glow and afterglow needed to attain a maximum discharge current are (70 us) and (60 us), respectively. The discharge current is observed to drop to the lowest value when the two times are serially longer than (85 us) and (72 us). Furthermore, the difference between the two times required to obtain a maximum rate of change in the discharge current, or a maximum discharge current, is deduced to be comparable to the breakdown time delay of gases reported in the literature. These observations can be useful for the design of plasma devices requiring specialized engineering.
The aim of this research is to study the effect of using computer
techniques to increase students information at the experimenting the speed
control of dc motor by the magnetic field.
Simulation of the experiment has been used by implementing
“Electronics Workbench” software.
The random sample, included (30) second year electrical department
students, divided into two groups , experimental and control with pre-test and
post-test .
The results showed great advantages for the experimental group
through the use of computer program in the laboratory. The calculated (t) was
(10.6) which was significant and showed statistical differences between the
experimental and control group.
According to the result
هدفت هذه الدراسة إلى التعرف على دور نظام معلومات الموارد البشرية في تحقيق متطلبات عملية تقويم أداء أعضاء الهيئة التدريسية في كلية الإدارة والاقتصاد/جامعة بغداد. وقد تحددت مشكلة الدراسة في عدد من التساؤلات، أهمها: ما تأثير كل متغير من متغيرات نظام معلومات الموارد البشرية في عملية تقويم أداء أعضاء الهيئة التدريسية في الكلية المبحوثة؟ وما تأثير متغيرات نظام معلومات الموارد البشرية مجتمعة في عملية تقويم الأداء
... Show MoreNarrators who ruled Bukhari weak
In its great history, the small weak
And their strength Abu Hatim narrated by his son in his book wound and amendment
تواجه الوحدات الاقتصادية في العراق منافسة قوية بسبب مشكلات خاصة بإرتفاع الاسعار وارتفاع تكاليف الانتاج وضعف الاهتمام بدراسة السوق وغيرها من المشاكل ، فضلاً عن استخدام نظام التكاليف التقليدي الذي لا يوفر معلومات ملائمة لقرارات التسعير الامر الذي يتطلب دراسة وتحليل تلك المشكلات ومعالجتها بالاعتماد على تقنيات حديثة بما يمكنها من المنافسة ولهذا جاء هذا البحث والذي يعتبر من المداخل الحديثة لتخفيض التكاليف وم
... Show MoreMass transfer was studied using a rotating cylinder electrode with different lengths of legs acting as turbulence promoters. Two types of rotating cylinder ,made of brass, were examined : an enhanced cylinder one, with four rectangular extensions 10 mm long, 10 mm wide, and 1mm thick, and an enhanced cylinder two with four longitudes 30 mm long,10 mm wide, and 1mm thick. The best performance was obtained for enhanced cylinder two at low rotation speeds while enhanced cylinder one was realized at high rotation speeds. The mass transfer enhancement as compared with a normal rotating cylinder electrode, devoid of promoters, is 53% or 58% higher. The enhancement percentage decreased as rotation speeds increased further, since, seemingly, ful
... Show MoreObjective: To assess the functional outcome, time to union, shoulder pain, blood loss, operative time, iatrogenic radial nerve injury, hospitalization, and infection. Methodology: It is a prospective randomized study on 30 patients with mid-shaft humerus fracture according to AO classification (1.2A1, 2, 3 and 1,2B) with functioning radial nerve. They were randomly dividing into two groups. Group A were treated by a closed antegrade interlocking nail, and group B treated by open reduction and locked compression plate fixation. The follow-up was up to 6 months, including time to union, shoulder pain, intraoperative blood loss, operative time and iatrogenic radial nerve injury. Functional outcome was assessed by quick DASH score. Resu
... Show MoreAromatic Schiff-bases are known to have antibacterial activity, but most of these compounds are sparingly soluble in water. The present work describes the synthesis of new Schiff-bases derived from branched aminosugars. Treatment of 3-Amino-3-Cyano-3-Deoxy-1,2:5,6-Di-O-Isopropylene-α-D-Allofuranose (1) with the aldehydes (2) under reflux in methanol afforded the Schiff-bases (3) in good yields. The new Schiff-bases were in accord with their NMR, IR spectral data and elemental analysis.
Background: The present in-vitro study was undertaken to evaluate and compare fracture resistance of weakened endodontically treated premolars with class II MOD cavities restored with different bulk fill composite restorations (EverX posterior, Alert, Tetric EvoCeram Bulk Fill, and SDR). The type and mode of fracture were also assessed for all the experimental groups. Materials and Method: Forty-eight human adult maxillary premolar teeth were selected for this study. Standardized extensive class II MOD cavities with endodontic treatment were prepared for all teeth, except those that were saved as intact control. The teeth were divided into six groups of eight teeth each (n=8): (Group 1) intact control group, (Group 2) unrestored teeth with
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