Four different spectrophotometric methods are used in this study for the determination of Sulfamethoxazole and sulfanilamide drugs in pharmaceutical compounds, synthetic samples, and in their pure forms. The work comprises four chapters which are shown in the following: Chapter One: Includes a brief for Ultraviolet-Visible (UV-VIS) Absorption spectroscopy, antibacterial drugs and sulfonamides with some methods for their determination. The chapter lists two methods for optimization; univariate method and multivariate method. The later includes different types, two of these were mentioned; simplex method and design of experiment method. Chapter Two: Includes reaction of the two studied drugs with sodium nitrite and hydrochloric acid for diazotization reaction followed by coupling with diphenylamine in acidic medium to form, a blue colored azo dye compound which exhibits maximum absorption (λmax) at 530 nm for sulfamethoxazole complex and 531 nm for sulfanilamide complex against the reagent blank and the concentration of these drugs were determined spectrophotometrically. The optimum reaction conditions and other analytical parameters were evaluated. In addition to classical univariate optimization, modified simplex method has been applied in optimization of the variables affecting the color producing reaction. The results show better optical characteristics for calibration curves and statistical data were obtained under optimum conditions obtained by multi simplex optimization, in comparison with those obtained via univariate method for two studied drugs. Beer’s law obeyed in the concentration range of 0.5-12.0 μg.mL-1, 0.5-7.0 μg.mL-1 for sulfamethoxazole and sulfanilamide respectively with molar absorptivity of 4.9617×104 L.mol-1.cm-1 for sulfamethoxazole and 5.9185×104 L.mol-1.cm-1 for sulfanilamide. The detection limits were 0.036 μg.mL-1 and 0.016 µg.mL-1 for the two complexes respectively by simplex method. No interferences from the studied excipients on the determination of these drugs were found therefore, the proposed methods were applied successfully II for the determination of the sulfamethoxazole and sulfanilamide in pharmaceutical compound and in synthetic samples. Chapter Three: Is based on the formation of condensation complexes of each drug with sodium 1,2-naphthoquinon-4-sulfonate as a chromogenic reagent. The absorbance values, for the formed complexes were measured at 460 nm for sulfamethoxazole and 455 nm for sulfanilamide; against reagent blank. Different variables affecting the completion of reaction have been carefully optimized following the classical univariate sequence and design of experiment (DOE) method and the results were obtained under optimum conditions by (DOE) optimization which shows better optical characteristics for calibration curves and statistical data in comparison with those obtained via univariate method for two studied drugs. The calibration graphs are linear in the ranges of (5.0-50.0) µg.mL-1 for sulfamethoxazole and (5.0-30.0) µg.mL-1 for sulfanilamide with detection limit 0.359 µg.mL-1for sulfamethoxazole complex and 0.536 µg.mL-1 for sulfanilamide complex. The molar absorptivity was found to be (7.0918×104 L.mol-1.cm-1) for sulfamethoxazole and (7.0774×104 L.mol-1.cm-1) for sulfanilamide by the design of experiment (DOE) method. Finally no interferences from the studied excipients on the determination of these drugs were found. The proposed methods have been successfully applied for the determination of sulfamethoxazole and sulfanilamide in their pharmaceutical preparation and synthetic samples. Chapter Four: Includes two parts; Derivative spectrophotometry and partial least-squares (PLS). Derivative spectrophotometry is based on the first and second derivative spectra of absorption which has been applied for simultaneous spectrophotometric determination of sulfamethoxazole and sulfanilamide in their mixture in the ultraviolet region. The method offers an advantage of getting rid of the resulting error in the values of absorption because of the presence of each drug with the presence of interferences from the excipients. It was found that the method is able to accurately estimate sulfamethoxazole in the range of (2.0-50.0) μg.mL-1; in mixtures containing III (2.0-30.0) μg.mL-1 of sulfanilamide, as (interferent). The results obtained, with the first derivative measurements, indicate that when the concentration of sulfanilamide is kept constant and the concentration of sulfamethoxazole varied, the peak amplitudes are measured at peak-to-baseline (223, 254,287 nm), peak to peak height between (223- 254 nm), (254-287nm). Moreover, the height at the zero cross of sulfanilamide at (235.62, 258.72 nm), heightto-height of the two zero crosses between (235.62-258.72 nm) and area under peak between (241.95-267.04 nm), (267.04-330 nm) were found to be in proportion to the sulfamethoxazole concentration therefore they are used for the determination of it. The careful inspection of the second derivative spectra obtained for the mentioned mixtures of sulfamethoxazole and sulfanilamide shows that peak to basline is at (239.5, 263.5, 267.75, 301, 215 nm) , height to basline is at zero cross is at (245.86, 271.28 nm) , peak to peak is between (239.5-264.25 nm), (239.5-267.75 nm), (271.28-301 nm), (215-239.5 nm), height to height is at two zero cross (245.86-271.28 nm) in addition to peak area at the interval between (254.12-281 nm), (286.95- 329.5 nm), (221.75-254.12 nm) measurements at specified wavelength could be used to quantify the exact concentration of sulfamethoxazole in presence of sulfanilamide. Sulfanilamide was determined for the range of (2.0-50.0) μg.mL-1; in a mixture containing (2.0-50.0) μg.mL-1 of sulfamethoxazole as (interferent). The procedure gave good results over the studied range of concentration depending on peak-to-baseline at (224, 246, 271 nm), height at zero cross at (241.95, 267.04 nm), peak to peak between (224-246 nm), (246-271 nm), height to height at two zero cross (241.95-271 nm) and area under the peak at (235.62-258.72 nm) measurements were found to be used for the determination of sulfanilamide in the first derivative technique. On other situation, the wavelengths are at 218 nm, 231 nm, 260 nm and 278 nm (peak to base line measurements), and height at two zero cross at 254 nm and 281 nm, and peak to peak measurements between (218-231 nm), (231-260 nm) and (260-278 nm), and height at zero cross at (254, 281 nm), wavelengths at (210-224 nm) , (224-245.84 nm) and (271.28-330 nm) peak area at the interval measurements were used for the estimation of sulfanilamide on second derivative.
Some children are suffering from introversion in kindergartens , so it must be confront and obviated by specialists because it will inevitably lead to unsatisfactory results reflect negatively on the individual and the community together . And the introvert child is a miserable child incapable of social interaction or give - and - take with colleagues , lack of integration of the child to life leads to the obstruction of participation with his peers in various activities. Introversion causes a real emotional deficit to the children of kindergartens which limits of possibility of their intellectual development and mental growth and that because of their isolation and poor focus in education
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In this paper, a compartmental differential epidemic model of COVID-19 pandemic transmission is constructed and analyzed that accounts for the effects of media coverage. The model can be categorized into eight distinct divisions: susceptible individuals, exposed individuals, quarantine class, infected individuals, isolated class, infectious material in the environment, media coverage, and recovered individuals. The qualitative analysis of the model indicates that the disease-free equilibrium point is asymptotically stable when the basic reproduction number R0 is less than one. Conversely, the endemic equilibrium is globally asymptotically stable when R0 is bigger than one. In addition, a sensitivity analysis is conducted to determine which
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This study investigates the Linguistic and Conceptual equivalence of Conner’s Revised Scales when applied on a Sudanese sample. Sudanese parents and teachers completed behavior-rating scales on a stratified sample of 200 children. These instruments were based on Conner’s parent -48 and teacher-28 questionnaires. Following a reliable translation into Sudanese Arabic the test-retest reliability of the items and the internal consistency of the original Conner’s' revised scales were explored. The associations between scale scores and between parents and teachers scores were also examined. Both instruments displayed good reliability and the original Conners scales had satisfactory internal consistency. The inter-correlation sugg
... Show MorePortland cement concrete is the most commonly used construction material in the world for decades. However, the searches in concrete technology are remaining growing to meet particular properties related to its strength, durability, and sustainability issue. Thus, several types of concrete have been developed to enhance concrete performance. Most of the modern concrete types have to contain supplementary cementitious materials (SCMs) as a partial replacement of cement. These materials are either by-products of waste such as fly ash, slag, rice husk ash, and silica fume or from a geological resource like natural pozzolans and metakaolin (MK). Ideally, the utilization of SCMs will enhance the concrete performance, minimize
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