Abstract. Shock chlorination is a well-known practice in swimming pools and domestic wells. One of the limitations for using this technique in drinking water purification facilities is the difficulty of quickly removing high chlorine concentrations in water distribution systems or production facilities. In order to use this method in the drinking water industry a shock de-chlorination method should be introduced for producing microorganism and biocide free water. De-chlorination using natural stagnant aeration (leaving the water to lose the chlorine naturally) is the safest known method if compared with chemical and charcoaling methods. Unfortunately, stagnant aeration is a slow process. Therefore, developing a process for accelerating de-chlorination by aeration would pave the way for using shock de-chlorination in drinking water industry. Forced air bubbling is a possible technique for de-chlorination but there is lack of data supporting such a process. The theory is that air bubbling has the advantages of higher mass transfer area, higher Reynolds number across the bubble water interface, and higher mass transfer concentration gradient as the bubbling presents a continuous stream of fresh bubbles. All of these factors accelerate aeration to various extents. A 20 cm diameter, 1-meter height column provided with air sparger was designed to collect the desired data used in this study. Trichloroisocyanuric acid, sodium hypochlorite and chlorine gas were the three familiar sources of chlorine used to investigate their response to air bubbling. Chlorine gas was the fastest and safest chlorine source to be dechlorinated. It dropped from 200 ppm to 0.02 ppm within 4 minutes or zero ppm within 6 minutes using an air flowrate of 9 l/min. Sodium hypochlorite decreased from 200 ppm to 0.02 ppm within 6 minutes using air flowrate of 9 l/min. Trichloroisocyanuric acid found to be the chlorine source slowest to respond to de-chlorination. It decreased from 200 ppm to 0.02 ppm within 8 minutes using an air flowrate of 9 l/min. Shock de-chlorination by aeration is found to be a promising method that opens up the drinking water industry and could produce microorganism and biocide free drinking water.
In this research, the focus was placed on estimating the parameters of the Hypoexponential distribution function using the maximum likelihood method and genetic algorithm. More than one standard, including MSE, has been adopted for comparison by Using the simulation method
AS Muhsen, International Journal of Psychosocial Rehabilitation (1475-7192), 2020 - Cited by 1
This study were implemented on (60) broiler chick with one day age divided into three equal groups , first one was given basal diet while group two and three given adiet contain 0.01% ,0.02% tryptophan respectively for 7 weeks . The results show that the chicks recevd the tryptophan have asigneficant increasment in hemoglobin concentration, red blood cells count, packed cell volume and increased the level of globuline concentration and lymphocyte % which mean that the addition of tryptophan improve blood picture charactores and the immunity of the broiler chickens and this evident from the good health state and decrease the mortality among birds .
Iron oxide (Fe3O4) nanoparticles were synthesized via an eco-friendly green approach by adding Phoenix dactylifera extract to the aqueous solution of ferric chloride. The effect of annealing temperature (Ta) (100-150) °C on particle size was studied. X-ray diffraction (XRD), UV-visible spectroscopy, atomic force microscopy (AFM), and field emission scanning electron microscopy (FESEM) were used to evaluate the produced nanoparticles. According to XRD spectra, the crystallite size of the samples was determined using the Scherrer formula. AFM and FE-SEM were used to determine surface morphology. A UV-Vis optical spectroscopic examination was carried out to determine the band gap energy of the iron oxide nanoparticles. It was found th
... Show MoreBACKGROUND: Volar Barton’s fracture is a shearing mechanism of injury that results in fracture and subluxation of distal end radius in which volar rim of the distal radius is displaced with hand and carpus. Open reduction and volar plate fixation ensure more stable change of displacement, preservation of reduction, and early mobilization. AIM: This study aims to assess the functional and radiological outcome results of volar Barton’s fracture treated by volar buttress plate using the demerit points system of Gartland and Werley. PATIENTS AND METHODS: This study is a prospective descriptive observational study on 32 patients who were treated with ORIF by volar buttress plate for isolated volar Barton’s fractures between Fe
... Show MoreNowadays nanoparticles are used in many fields of life all over the world, and there are numerous ways to obtain them: chemical, physical and biological processes. In recent times, the biological method for the synthesis of nanoparticles associated with using plant extract is widely spread. Optimal conditions for synthesis of silver nanoparticles using aqueous seeds extract of Myristica fragrance were highlighted in this research, such as type of plant extract, weight of extracted plant material, volume ratio of plant extract to AgNO3 and temperature of reaction. The study proved that the optimal status for AgNPs synthesis by using 10 g of M. fragrance seeds powder were added to 100 mL boiled distilled water, then homogenized and filt
... Show MoreThis deals with estimation of Reliability function and one shape parameter (?) of two- parameters Burr – XII , when ?(shape parameter is known) (?=0.5,1,1.5) and also the initial values of (?=1), while different sample shze n= 10, 20, 30, 50) bare used. The results depend on empirical study through simulation experiments are applied to compare the four methods of estimation, as well as computing the reliability function . The results of Mean square error indicates that Jacknif estimator is better than other three estimators , for all sample size and parameter values