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.
The existing study aimed to assess four soil moisture sensors’ capacitive (WH51 and SKU: S EN0193) and resistive (Yl69 and IC Station) abilities, which are affordable and medium-priced for their accuracy in six common soil types in the central region of Iraq. The readings’ calibration for the soil moisture sensor devices continued through two gravimetric methods. The first depended on the protocols’ database, while the second was the traditional calibration method. The second method recorded the lowest analysis error compared with the first. The moderate-cost sensor WH51 showed the lowest standard error (SE), MAD , and RMSE and the highest R² in both methods. The performance accuracy of WH51 was close to readings shown by the manufac
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Wettability of CO2-brine-mineral systems plays a vital role during geological CO2-storage. Residual trapping is lower in deep saline aquifers where the CO2 is migrating through quartz rich reservoirs but CO2 accumulation within a three-way structural closure would have a high storage volume due to higher CO2 saturation in hydrophobic quartz rich reservoir rock. However, such wettability is only poorly understood at realistic subsurface conditions, which are anoxic or reducing. As a consequence of the reducing environment, the geological formations (i.e. deep saline aquifers) contain appreciable concentrations of various organic acids. We thus demonstrate here what impact traces of organic acids exposed to storage rock have on their wettabil
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The construction industry plays a crucial role in the countries' economy, especially in the developed country. This point encourages the concerned institution to use new techniques and integrate many techniques and methods to maximize the benefits. The main objective of this research is to evaluate the use of risk management, value management, and building information modeling in the Iraqi construction industry. The evaluation process aims at two objectives. The direct objective was to evaluate the knowledge in risk management (RM), value management (VM), and building information modeling (BIM). The indirect objective was to support the participants with information related to the main items mentioned. The questionnaire
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The effects of three different additives formulations namely Lubrizol 21001, HiTEC 8722B and HiTEC 340 on the efficiency of VII namely OCP of three base lubricating oils namely 40 stock and 60 stock and 150 stock at four temperatures 40, 60, 80 and 100oC were investigated. The efficiency of OCP is decreased when blended with 4 and 8 wt% of Lubrizol 21001 for all the three base oil types. But it is increased when adding 4 wt% and 8 wt% of H-8722B in 40 stock. While for 60 stock and 150 stock the OCP efficiency decreased by adding 4 and 8 wt% of H-8722B. In the other hand, it is decreased with a high percentage by adding 4 and 8 wt% of H-340 for 60 stock and 150 stock and for 40 stock it is increased by adding 4 wt% of H-340 and decreased
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The loose sand is subject to large settlement when it is exposed to high stresses. This settlement is due to the nature of the high drainage of sand, which displays foundations and constructions to a large danger. The densification of loose sandy soils is required to provide sufficient bearing capacity for the structures. Thus soil stabilization is used to avoid failure in the facilities. Traditional methods of stabilized sandy soil such as fly ash, bituminous, and cement often require an extended curing period. The use of polymers to stabilize sandy soils is more extensive nowadays because it does not require a long curing time in addition to being chemically stable. In this study, the effect of adding different percent
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Electro-chemical Machining is significant process to remove metal with using anodic dissolution. Electro-chemical machining use to removed metal workpiece from (7025) aluminum alloy using Potassium chloride (KCl) solution .The tool used was made from copper. In this present the optimize processes input parameter use are( current, gap and electrolyte concentration) and surface roughness (Ra) as output .The experiments on electro-chemical machining with use current (30, 50, 70)A, gap (1.00, 1.25, 1.50) mm and electrolyte concentration (100, 200, 300) (g/L). The method (ANOVA) was used to limited the large influence factors affected on surface roughness and found the current was the large influence f
... Show MoreThe primary components of successful engineering projects are time, cost, and quality. The use of the ring footing ensures the presence of these elements. This investigation aims to find the optimum number of geogrid reinforcement layers under ring footing subjected to inclined loading. For this purpose, experimental models were used. The parameters were studied to find the optimum geogrid layers number, including the optimum geogrid layers spacing and the optimum geogrid layers number. The optimum geogrid layers spacing value is 0.5B. And as the load inclination angle increased, the tilting and the tilting improvement percent for the load inclination angles (5°,10°,15°) are (40%,28%, and 5%) respectively. The reduction percent o
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In order to promote sustainable steel-concrete composite structures, special shear connectors that can facilitate deconstruction are needed. A lockbolt demountable shear connector (LB-DSC), including a grout-filled steel tube embedded in the concrete slab and fastened to a geometrically compatible partial-thread bolt, which is bolted on the steel section's top flange of a composite beam, was proposed. The main drawback of previous similar demountable bolts is the sudden slip of the bolt inside its hole. This bolt has a locked conical seat lug that is secured inside a predrilled compatible counter-sunk hole in the steel section's flange to provide a non-slip bolt-flange connection. Deconstruction is achieved by demounting the tube from the t
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In this study tungsten oxide and graphene oxide (GO-WO2.89) were successfully combined using the ultra-sonication method and embedded with polyphenylsulfone (PPSU) to prepare novel low-fouling membranes for ultrafiltration applications. The properties of the modified membranes and performance were investigated using Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), contact angle (CA), water permeation flux, and bovine serum albumin (BSA) rejection. It was found that the modified PPSU membrane fabricated from 0.1 wt.% of GO-WO2.89 possessed the best characteristics, with a 40.82° contact angle and 92.94% porosity. The permeation flux of the best membrane was the highest. The pure water permeation f
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Nimodipine (NMD) is a dihydropyridine calcium channel blocker useful for the prevention and treatment of delayed ischemic effects. It belongs to class ? drugs, which is characterized by low solubility and high permeability. This research aimed to prepare Nimodipine nanoparticles (NMD NPs) for the enhancement of solubility and dissolution rate. The formulation of nanoparticles was done by the solvent anti-solvent technique using either magnetic stirrer or bath sonicator for maintaining the motion of the antisolvent phase. Five different stabilizers were used to prepare NMD NPs( TPGS, Soluplus®, HPMC E5, PVP K90, and poloxamer 407). The selected formula F2, in which Soluplus
has been utilized as a stabilizer, has a par
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