Various types of storing tanks are used to store municipal water at homes. This study was carried out to examine several water physical and chemical variables such as pH, EC, TSS and TDS after different storing periods. The obtained results showed no significant differences between the mean of pH values which ranged from 7.27 ± 0.04 in a water sample of galvanized tank after six days of storing to 8.10 ± 0.12 in water sample of aluminum tank after nine storing days. In case of electric conductivity, Highest mean values (1.85±0.09 μS/cm and 1.44 ± 0.21μS/cm) were found in galvanized tank samples for different storing periods while the lowest mean values (0.58±0.06 μS/cm and 1.04±0.06 μS/cm) were recorded in aluminum tank samples. However in plastic tanks samples, the mean values were moderated (0.94 ±0.05 μS/cm and 1.16±0.03 μS/cm) between means of both tanks. In case of TSS, the current data have shown significant differences between mean values of examined stored water samples where highest values (730.0±31.97 mg/l - 1060.0±141.42 mg/l) were in galvanized tank water samples and the lowest mean values (27.67±21.36 mg/l – 118.33 ±18.46 mg/l) were in plastic tank water samples whilst in aluminum tank water samples, these values were varied from 193.33±10.66 mg/l – 253.33±22.2 mg/l). In general, only water samples stored in galvanized tank had mean value significantly higher that of control sample which had 251.33±3.21 mg/l. Regarding TDS, this study has found that highest mean values (800.0±40.0 mg/l – 1600.0±100.0 mg/l) were recorded in water samples of aluminum tank and the lowest mean values (40.0±10.0 mg/l – 120.0±10.0 mg/l) were found in water samples of plastic tank while water samples of galvanized tank had mean values varied from 680.0 ±10.0 mg/l – 1172.0 ±18.08 mg/l. Control sample, however had mean value of 495.0±5.0 mg/l which was only higher than that of plastic tank
Phosphorus is usually the limiting nutrient for eutrophication in inland receiving waters; therefore, phosphorus concentrations must be controlled. In the present study, a series of jar test was conducted to evaluate the optimum pH, dosage and performance parameters for coagulants alum and calcium chloride. Phosphorus removal by alum was found to be highly pH dependent with an optimum pH of 5.7-6. At this pH an alum dosage of 80 mg/l removed 83 % of the total phosphorus. Better removal was achieved when the solution was buffered at pH = 6. Phosphorus removal was not affected by varying the slow mixing period; this is due to the fact that the reaction is relatively fast.
The dosage of calcium chloride and pH of solution play an importa
study was conducted on a stretch of Tigris river crossing Baghdad city to determine the concentration of some chlorophenols pollutants. Aqueous samples were preliminary enriched about 500 times and the chlorophenols have determined using high performance liquid chromatography HPLC. Limits of detection LOD were (0.007–0.012 mg L-1), relative standard deviations RSD% were 2.4%–5.59% and relative recoveries were 51.06%– 104.07%. The existence of chlorophenols in Tigris river was in the range 0.023–4.596 mg L-1. The developed method suggested in this study can be applied for routine analysis and monitoring of chlorinated phenols in environmental aqueous samples.
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Interest in the teaching profession is one of the most important steps on the road to education reform to develop the quality of education is not only through the teacher's professional competencies required, interest in the teaching profession in any society stems from fingerprints left by the teacher on his behavior and morals and their minds and their personalities. Today we are going to provide scientific, technical and research is enormous, we need more powerful skills and ways of thinking that must be acquired by the teacher. The current search is gaining importance in terms of:
- This is the first of its kind on the researcher's knowledge _ which deals with the modern trends in t
The study aims to identify the acceptability of drinking water for human consumption depend on Iraqi specification and WHO standards. Samples collected monthly for each station from March to December2014. The samples collected from six stations distributed in Baghdad City, the first two stations located in al-Kadmyai area , the 3rd and 4th located in AL- Doora while the last two stations located in Al-Amryai area. The study measured physical, chemical and bacteriological factors. The measured parameters were ranged each for pH 6.63-7, turbidity 0.4-1.3NTU,TDS394.2-960mg/l,total hardness 259.1-578while Ca and Mg were 43-134,20.1-72 mg /l respectively. Other chemical parameters like chloride ranged from 56.8-184 mg/l and heavy metals range
... Show MoreBackground: To evaluate the ISO depth of cure of bulkfill composites and depth of cure which determined by Vickers microhardness test. Materials and Methods: Bulkfill resin composite specimens (n=150) were prepared of three bulkfill composite materials (TetricEvo Ceram, Quixfil and SDR) and light cured by Flash max p3 for 3, 10, 20 seconds and by wood pecker for 10, 20 seconds respectively, a mold was filled with one of the three bulkfill composites and light cured. The specimens removed from the mold and scraped by plastic spatula and the remaining length (absolute length) was measured which represent the ISO depth of cure. After that the specimens were returned into the mold and a microhardness indentation device applied on the specimen
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Background: The mechanical and physical properties of Polymethyl methacrylate (PMMA) don’tfulfill the entire ideal requirements of denture base materials. The purpose of this study was to produce new modified polymer nanocomposite (PMMA /ZrO2-TiO2) andassess itsimpact strength, transverse strength and thermal conductivity in comparison to the conventionalheat polymerized acrylic resin. Materials and Methods: Both ZrO2 and TiO2nano fillers were silanized with TMSPM (trimethoxysilyl propyl methacrylate) silane coupling agent before beingdispersed by ultrasonication with the methylmethacrylate (monomer) and mixed with the polymer by means of 2% by weight in (1:1) ratio, 60 specimens were constructed by conventional water bath processing
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In this research Epoxy resin was reinforced by nano alumina (AL2O3) particles in grain size(25-30 nm) with two weight ratios (2,4)% then compared with pure Epoxy. Four mechanical tests were performed on these materials include Hardness, flexural, impact & compression strengths before and after immersion in tap water and chemical solutions (CH3COOH) acid, (KOH) base at (0.5N) ,The diffusivity coefficients of all prepared samples were calculate after immersion in water and chemical solutions mentioned above , the results were showed that the Flexural, Impact & Hardness increase after addition the ceramic particles (AL2O3) while the immersion process results showed illustrated different values from sample to other.
Background: The fracture of instruments within root canal during endodontic treatment is a common incidence, fracture because of fatigue through flexure occurs due to metal fatigue, this study aimed to assess the effect of curvature angle and rotational speed on the cyclic fatigue of different type of Endodontic NiTi Rotary Instruments and compare among them. Materials and method: Three types of rotary instruments with tip size 0.25: ProTaPer F2 (Densply, Malifier) Revo-S SU( 0.06 taper, MicroMega) and RaCe system (0.06 taper, FKG, Dentaire), Forty file of each instrument were used within two canals with angle of curvature (40 &60 )at two speed (250&400)RPM, twelve group were formed for all instruments(total number=120),ten file fo
... Show MoreThe purpose of this study was to find out the connection between the water parameters that were examined in the laboratory and the water index acquired from the examination of the satellite image of the study area. This was accomplished by analysing the Landsat-8 satellite picture results as well as the geographic information system (GIS). The primary goal of this study is to develop a model for the chemical and physical characteristics of the Al-Abbasia River in Al-Najaf Al-Ashraf Governorate. The water parameters employed in this investigation are as follows: (PH, EC, TDS, TSS, Na, Mg, K, SO4, Cl, and NO3). To collect the samples, ten sampling locations were identified, and the satellite image was obtained on the
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