The main factors that make it possible to get the corrosion of reinforcing steel in concrete are chloride ions and the absorption of carbon dioxide from the environment, and each of them works with a mechanism which destroys the stable immunity of rebar in the concrete. In this work the effect of carbon dioxide content in the artificial concrete solution on the corrosion behavior of carbon steel reinforcing bar (CSRB) was studied, potentiostatically using CO2 stream gas at 6 level of concentrations; 0.03 to 2.0 weight percent, and the effect of rising electrolyte temperature was also followed in the range 20 to 50ᴼ C. Tafel plots and cyclic polarization procedures were obeyed to investigate the corrosion parameters and pitting susceptibility respectively. The change in the microstructure and morphology of the CSRB after polarization in the simulate concrete solution was studied using optical and atomic force microscopes. The results show that the corrosion rate of the CSRB in artificial concrete greatly increases with the existence of CO2 gas and highly depends on its concentration in the range 0.03 to 2.0% .No sign for pitting corrosion is recorded at all CO2 concentrations and the general corrosion is the main problem in the conditions under consideration.
The aggregation capacity of human reb blood cells lies between that of the non- aggregated arythrocyte and the remarkably full sedimentation. As the ability to aggregate is atributed to many factors such as the availability of macromolecules and plasma lipids, the role of plasm lipid profile on RBC aggregation and sedimentation changes in normal and diabetic patients is studied.Also serum lipid profile measurement (Total cholesterol, Triglyceride, HDL, LDL, VLDL) in normal and diabetic subjects were made. The principle of measurement includes detecting the transmitted laser light through a suspension of 10% diluted red blood cells in plasma. In all diabetics, the raulux formation and sedimentation rate is enhanced.
Electrochemical Grinding (ECG) process is a mechanically assisted electrochemical process for material processing. The process is able to successfully machine electrically conducting harder materials at faster rate with improved surface finish and dimensional control. This research studies the effect of applied current, electrolyte concentration, spindle speed and the gap between workpiece and tool on hardness and material removal rate during electrochemical grinding for stainless steel 316. The characteristic features of the electrochemical grinding process are explored through Taguchi-design-based experimental studies. The better hardness can be obtained at 10 A of the current, 150 g/l of the electrolyte concentration, 0.3 mm of gap an
... Show MoreConstruction is the opening of the important pillars of the construction of the film as a whole for this, we find that the first of any narrative of my film begin at the borders of this construction is the window that we look through the contents tale and puzzle narrative is of significance that degrade traveler when reservoirs expression later in reasoning and find justifications ills that came by those initiation, this initiation may be the window that lead us to the core, understanding the story through signals received to the recipient to sail because of the paths of pickling what is which is encoded, but this initiation may serve as keys that understanding the be puppies and signals that beset and surrounded to what He holds inevita
... Show MoreSelf-compacting concrete (SCC) is an innovative concrete that does not require vibration for placing and compaction. It is able to flow under its own weight, completely filling formwork and achieving full compaction, even in the presence of congested reinforcement. The effect of external sulfate attack was studied-Es (very sever exposure SO4>10000ppm) according to ACI 318-11. The mix design method of SCC used is according to EFNARC 2002, and then must satisfy the criteria of filling ability, passing ability and segregation resistance. The experimental program focuses to study two different chemical composition of sulfate resistance Portland cement with different percentage of silica fume replacement by weight of cement and W/cm (0.3 and 0.3
... Show MoreThis researchable paper aims to focus of the role & mechanism of market makers in Iraqi stock market through analyzing its role in other Arabian as well as global stock ones, especially in current period through activate the use of bonds, shares, and trying to create a continued price balance. Then decreasing the opportunity having gaps between highest and lowest level without reasonable causes. In addition trying to deactivate the common decision without supported information. Moreover, this paper aims to explain the rules of increasing liquidity and having balance to lead the market into positive direction. Thus, for achieving the above-mentioned requirements, such conditions should be underlined by market makers as well as t
... Show MoreMany countries are very important in their interest not only in diversifying foreign reserves, but in determining and planning their volume in accordance with the goals set, namely facing potential external shocks, as the research aims to determine the extent of the strength of foreign reserves in the possession of the Central Bank in relation to every influential variable in the Iraqi economy. , in order to determine the minimum level of reserves that requires reconsideration of the exchange rate, as the research adopted the inductive analytical method in analyzing real (Quantitative data) for the research variables in the years of study, as the research adopted a set of analytical indicators approved by the International Moneta
... Show MoreAbstract:
Taghlib tribe had an important part in the history of the first century of
hijra. She managed to get the best social, economic and political basis in the
Arab- Islamic state. In this basis Taghlib was the best Dhimies in the Islamic
state. This tribe refused to be among the people of the book, and to be from
the people of dhima. That tribe refused to pay the Jizya and Khraj, but
accepted to pay double Sadaqa in stead of Jizya and Khraj, so in that case
many Muslims become angry.
Although their Christianity was naïve and simple, Taghlib hold it until the
end of the third century A.H. Taghlib did so because her people wanted to
keep their good relation with the Byzantine. Taghlib thought that the