Tigris River is one of the main important surface water resources in Iraq. This necessitates continuous study of its quality . The present study is concerned with the characteristics and quality of Tigris water passing through in Baghdad city. (eight) samples were collected from the river in the area Grea't City. The study periods were carried over four season, which has been sampled once represent the every season. First sampling 12-11-2012 represent the autumn season The second sampling 20-1-2013 to represent the winter season. The third in 25-3- 2013 to represent the Springer season. The fourth during 29-5-2013 to represent the summer spring season. In order to specify the water quality, a group of physical and chemical analyses have been conducted. The physical measurements included the temperature, and the Specific electrical Conductance while the chemical analyses included measuring the pH , hardness , Salinity, alkalinity, Total Dissolved Solids(TDS) , and total suspended solids (TSS),Chemical Oxygen Demand (COD ) and measuring the quantity of greases and oils via the gravimetric methods. The chemical analyses also included measuring the anions such as the (Sulphate (SO4 -2), phosphate (pO4 -3) and Nitrate (NO3 -) by using the techniques of the UV – VIS Spectrophotometer.In order to identify the main cations in the water , the concentration of K+2,Ca+2 and Mg+2 were measured . The above mentioned analyses varied from using the classical chemical analyses such as titration as in measuring the [Cl- , (HCO3 - ,Ca+2 ,Mg+2 ]Ions.Owing to the importance of assessing the trace and heavy metals in water due to their direct effect on human health and reliability, metals were measured; Flame Atomic Absorption spectrophotometer was used to measure the metals . Also, The correlation coefficients between the quality parameter pairs of the river water samples were calculated in order to indicate the nature and the sources of the polluting substances.all results are not matched with the values of national (Central Organization for Standardization and Quality Control) and international except(pH &E.C.) but (HCO3 - &Mg+2 ,Ca+2 ) and heavy metals where matched in some station and not in others.
A metal-assisted chemical etching process employing p-type silicon wafers with varied etching durations is used to produce silicon nanowires. Silver nanoparticles prepared by chemical deposition are utilized as a catalyst in the formation of silicon nanowires. Images from field emission scanning electron microscopy confirmed that the diameter of SiNWs grows when the etching duration is increased. The photoelectrochemical cell's characteristics were investigated using p-type silicon nanowires as working electrodes. Linear sweep voltammetry (J-V) measurements on p-SiNWs confirmed that photocurrent density rose from 0.20 mA cm-2 to 0.92 mA cm-2 as the etching duration of prepared SiNWs increased from 15 to 30 min. The
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Activated carbon was Produced from coconut shell and was used for removing sulfate from industrial waste water in batch Processes. The influence of various parameter were studied such as pH (4.5 – 9.) , agitation time (0 – 120)min and adsorbent dose (2 – 10) gm.
The Langmuir and frandlich adsorption capacity models were been investigated where showed there are fitting with langmmuir model with squre regression value ( 0.76). The percent of removal of sulfate (22% - 38%) at (PH=7) in the isotherm experiment increased with adsorbent mass increasing. The maximum removal value of sulfate at different pH experiments is (43%) at pH=7.
Recycling process presents a sustainable pavement by using the old materials that could be milled, mixed with virgin materials and recycling agents to produce recycled mixtures. The objective of this study is to evaluate the impact of water on recycled asphalt concrete mixtures, and the effect of the inclusion of old materials into recycled mixtures on the resistance of water damage. A total of 54 Marshall Specimens and 54 compressive strength specimens of (virgin, recycled, and aged asphalt concrete mixtures) had been prepared, and subjected to Tensile Strength Ratio test, and Index of Retained Strength test. Four types of recycling agents (used oil, oil + crumb rubber, soft grade asphalt cement, and asphalt cement + Su
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The process of transformation from the central economy to a free economy requires restructuring the economy according to a new economic philosophy that relies on activating the role of private economic activity in which private and medium-sized institutions occupy an essential axis for their active role in the economies of all countries, especially those countries that have directed towards the market mechanism and sector leadership. The special process of economic development and the role that commercial banks can play in advancing the financing of these projects by establishing specialized business incubators for financing.
What encouraged countries to pay attention to these institutions is the ease of
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