The adsorption of hexavalent chromium by preparing activated carbon from date seeds with zinc chloride as chemical activator and granular date seeds was studied in a batch system. The characteristics of date seeds and prepared activated carbon (ZAC) were determined and found to have a surface area 500.01 m2/g and 1050.01 m2/g , respectively and iodine number of 485.78 mg/g and 1012.91 mg/g, respectively. The effects of PH value (2-12), initial sorbate concentration(50-450mg/L), adsorbent weight (0.004-0.036g) and contact time (30-150 min) on the adsorption process were studied . For Cr(VI) adsorption on ZAC, at 120 min time contact, pH solution 2 and 0.02 adsorbent weight will achieve an amount of 35.6 mg/g adsorbed . While when use date seeds as adsorbent , conditions of 3 solution pH, 0.02 absorbent weight , and 120 contact time gave 26.49 mg/g adsorbed amount. Using both Langmuir, Freundlich and Sips models were explain the dsorption isotherms. It declare that the Sips model fits well with the experimental data with a maximum Cr( VI) adsorption capacity for (ZAC) and granular date stone 233.493 and 208.055 mg/g, respectively . The kinetics data which obtained at different initial Cr(VI) concentrations were examined by using pseudo-first-order, pseudo-second-order, and intra-particle diffusion models . The result gained showed that the second-order model was only describing well the empirical kinetics data of both (ZAC) and granular date seeds. It was noticed that the granular date seeds has adsorption performance lower than the (ZAC).
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The simulation of passively Q-switching is four non – linear first order differential equations. The optimization of passively Q-switching simulation was carried out using the constrained Rosenbrock technique. The maximization option in this technique was utilized to the fourth equation as an objective function; the parameters, γa, γc and β as were dealt with as decision variables. A FORTRAN program was written to determine the optimum values of the decision variables through the simulation of the four coupled equations, for ruby laser Q–switched by Dy +2: CaF2.For different Dy +2:CaF2 molecules number, the values of decision variables was predicted using our written program. The relaxation time of Dy +2: CaF2, used with ruby was
... Show MoreBackground: Cyclophosphamide is an alkylating agent that is effective against a broad spectrum of tumors, with nephrotoxicity as a side effect. Irigenin is a natural isoflavonoid isolated from the rhizome of Belamcanda chinensis that has been reported to exert antioxidant activities. Objective: Evaluating the possible protective effects of irigenin on cyclophosphamide-induced nephrotoxicity in male rats. Methods: Fifty apparently healthy male albino rats were divided into five groups: (control, induction, irigenin, irigenin with cyclophosphamide, and vitamin E with cyclophosphamide. At the end of the experiment (day 29), all rats were sacrificed. Different parameters were evaluated, including urea and creatinine serum concentration,
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Surface runoff is considered one of the most significant water resources in arid and semi-arid environments. Estimating the volume of surface runoff through the application of Geographic Information Systems (GIS), along with maps detailing the geomorphological and geological characteristics of the Wadi Haran basin, is an essential process. This estimation is supported by mathematical equations based on the Soil Conservation Service Curve Number method (SCS-CN), which is among the most widely used approaches for calculating runoff volume. The study area, Wadi Haran basin, covers approximately 1,895 km². The Curve Number (CN) was found to be 92, with runoff volume (QV) values ranging between 582.71 m³ and 12.85 m³. The total surfa
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This article introduces a novel procedure to detect an approximate solution to Fredholm fractional integro-differential equations with linear type (LFFIDE) defined using Caputo fractional derivative. The new procedure approximates the solution using three types of polynomials: Laguerre polynomials, Hermite polynomials, and Legendre polynomials, thereafter transforming the problem into a linear programming problem. The approximate solutions are compared using testing examples to examine the efficiency of the suggested approach. Also, a comparison with the other methods using the same polynomials illustrates The effectiveness and consistency of the proposed technique. Finally, the error analysis of the proposed technique and convergent are di
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The fall angle of sun rays on the surface of a photovoltaic PV panel and its temperature is negatively affecting the panel electrical energy produced and efficiency. The fall angle problem was commonly solved by using a dual-axis solar tracker that continually maintains the panel orthogonally positioning to the sun rays all day long. This leads to maximum absorption for solar radiation necessary to produce maximum amount of energy and maintain high level of electrical efficiency. To solve the PV panel temperature problem, a Water-Flow Double Glazing WFDG technique has been introduced as a new cooling tool to reduce the panel temperature. In this paper, an integration design of the water glazing system with a dual-axis tracker has been ac
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