Cooling towers is one of the most important unit in industry, they are used to dispose heat from cooling media used in the integrated units. The choice of the cooling media plays recently an important rule due to fresh-water scarcity. The use of saline as a cooling media become of growing interest, but the corrosion problem has to be taken in consideration. In this study the simultaneous effect of cooling tower operation parameters on the corrosion rate of mild-steel is considered. The role of NaCl content is found to be pronounced more than the working solution temperature and flowrate. The corrosion of mild-steel in these studied factors had shown an interesting result especially with the NaCl% content. Firstly, there was an increase in the corrosion rate with increasing the salt content to 3.5% four times compared to that of 0%, but after a critical point (3.5%) the corrosion rate had been decreased to reach a level lower than that of pure water. While increasing the solution flowrate to 2.5 l/min and the temperature to 50°C will increase the corrosion rate by 25 and 20% respectively. From the results, it is obvious that the high concentration (>10%) of NaCl will inhibit the corrosion rate of mild-steel significantly and this prologue the gate to the use of saline instead of fresh water without hesitation
Background: Radioactive iodine-131 therapy is highly effective in treating patients with hyperthyroidism. An ablative dose is preferred by a number of endocrinologists, and, a fixed dose protocol seems to be better than a calculated dose in real practice.
Objective: To check for hypothyroidism in hyperthyroid patients one year after RAI therapy, comparing between the results of high ablative versus usual dosages of RAI-131.
Methods: This study included 174 hyperthyroid patients, 101 males and 73 females, divided into 2 groups, the first consisted of 162 patients given a usual fixed dose of RAI while the second consisted of 12 patients given a high fixed ablati
... Show MoreOur research is based on the fact that the reflection of entertainment programs in Arab satellite channels on the social behavior of Iraqi youth … a field analysis of the Arab ldol program) and that its importance is the entertainment programs and their reflection on social behavior، which occupies
large areas of time from Satellite channels in the form of various episodes and each episode contains several categories، or in the form of templates and forms of various goals and contents، but the problem of
research boils down to (how far iraqi youth follow the entertainment programs in Arab satellite channels and what are the motives for watching the Program Arab ldol )) by For Iraqi youth and what are the positive and negative
Abstract
The present study investigates the effect of acetic acid on corrosion behavior and its potential of hydrothermally sealed anodized AA2319-Al-alloys. Anodizing treatment was performed in stagnant phosphoric acid electrolyte with or without addition of acetic acid. Hydrothermal sealing was carried out in boiling water for each anodized specimen. The open circuit potential of the unsealed and sealed anodized samples was examined using open circuit potential measurement for the purpose of starting in scanning polarization diagrams. The potentiostatic polarization technique measurements were performed to assess corrosion behavior and sealing quality (i.e., degree of sealing) of
... Show MoreThe steel jetty selected for strengthening is in Baghdad city, over Tigris River, consists of 55 short spans, each of approximately 4 meters and one naviga-tional opening of 12 m. The bridge is 224 meters length and 8 meters in width. The strengthening system was designed to remove overstresses that occurred when the bridge was subjected to abnormal loads of 380 tons. A strengthening system which installed in spring 2008 was used where the main concept is to depend on added side supporting elements which impose reversal forces on the bridge to counteract most of the loads expected from the abnormal heavy loads. The bridge was load tested before and after the strengthening system was activated. The load test results indicate that the strengt
... Show MoreCarbon fibre reinforced polymers are widely used to strengthen steel structural elements. These structural elements are normally subjected to static, dynamic and fatigue loadings during their life-time. A number of studies have focused on the characteristics of CFRP sheets bonded to steel members under static, dynamic and fatigue loadings. However, there is a gap in understanding the bonding behaviour between CFRP laminates and steel members under impact loading. This paper shows the effect of different load rates from quasi-static to 300 × 103 mm/min on this bond. Two types of CFRP laminate, CFK 150/2000 and CFK 200/2000, were used to strengthen steel joints using Araldite 420 epoxy. The results show a significant bond strength enhancemen
... Show MoreThe electron mirror phenomenon has been explored to describe the behavior of a probing electron trajectory inside the chamber of scanning electron microscope (SEM). This investigation has been carried out by means of the modulated mirror plot curve technique. This method is based on expanding sample potential to a multipolar form to detect the actual distribution of the trapped charges. Actually an experimental result is used to guiding results of this work toward the accurate side. Results have shown that the influence of each type of multipolar arrangement (monopole, dipole, quadruple, octopole … etc.) mainly depends on the driving potential.
This research aims to introduce a new technique-off-site and self-form segmental concrete masonry arches fabrication, without the need of construction formwork or centering. The innovative construction method in the current study encompasses two construction materials forms the self-form masonry arches, wedge-shape plain concrete voussoirs, and carbon fiber-reinforced polymer (CFRP) composites. The employment of CFRP fabrics was for two main reasons: bonding the voussoirs and forming the masonry arches. In addition, CFRP proved to be efficient for strengthening the extrados of the arch rings under service loadings. An experimental test was conducted on four sophisticated masonry arch specimens. The research parameters were the Keystone thic
... Show More