In this paper, turbidimetric and reversed-phase ultra-fast liquid chromatography (UFLC) methods were described for the quantitative determination of ephedrine hydrochloride in pharmaceutical injections form. The first method is based on measuring the turbidimetric values for the formed yellowish white precipitate in suspension status in order to determine the ephedrine hydrochloride concentration. The suspended substance is formed as a result of the reaction of ephedrine hydrochloride with phosphomolybdic acid which was used as a reagent. The physical and chemical characteristics of the complex were investigated. The calibration graphs of ephedrine were established by turbidity method. While the second method (UFLC) was conducted using the methanol-water (55+45, v/v) as the mobile phase with adjusted water pH 3.5. The ephedrine hydrochloride was detected and measured using UV detector at 260 nm. The linearity of ephedrine was obtained in the range of 0.09–0.39 mmol·l-1 . The detection limits (LOD) for the ephedrine hydrochloride were found to be 0.4 and 0.0044 mmol·l-1 by turbidity and UFLC, respectively. The developed methods were successfully applied for the quantitative determination of ephedrine hydrochloride in laboratory preparations (standard) and in commercial pharmaceutical injections. The two methods have given relative standard deviations (R.S.D.) in the range of 0.65–1.69 %, which indicates reasonable repeatability and high precision of both methods.
In this work, a novel design for the NiO/TiO2 heterojunction solar cells is presented. Highly-pure nanopowders prepared by dc reactive magnetron sputtering technique were used to form the heterojunctions. The electrical characteristics of the proposed design were compared to those of a conventional thin film heterojunction design prepared by the same technique. A higher efficiency of 300% was achieved by the proposed design. This attempt can be considered as the first to fabricate solar cells from highly-pure nanopowders of two different semiconductors.
Seventy five isolates of Saccharomyces cerevisiae were identified, they were isolated from different local sources which included decayed fruits and vegetables, vinegar, fermented pasta, baker yeast and an alcohol factory. Identification of isolates was carried out by cultural microscopical and biochemical tests. Ethanol sensitivity of the isolates showed that the minimal inhibitory concentration of the isolate (Sy18) was 16% and Lethal concentration was 17%. The isolate (Sy18) was most efficient as ethanol producer 9.36% (v/w). The ideal conditions to produce ethanol from Date syrup by yeast isolate, were evaluated, various temperatures, pH, Brix, incubation period and different levels of (NH4)2HP04. Maximum ethanol produced was 10
... Show MoreDirect FIA methods for estimation of Naringenin (NG) in different samples were proposed. These methods are based on diazotization coupling reactions of two reagents: method (A) p-chloroaniline (PCA) and method (B) procaine hydrochloride (PRH) with NG in basic medium. Yellow dyes with maximum absorption at 416 and 415 nm were formed respectively. Calibration curves were constructed over different NG concentrations, linearity was from 1- 70 and 1- 40 µgmL-1 with detection limits of 0.55 and 0.24 µgmL-1 for (A) and (B) respectively. All analytical variables involved in the FIA procedure were evaluated and optimized. The established methods were successfully applied for the determination of NG in its supplements and u
... Show MoreHighly-fluorescent Carbon Quantum Dots (CQDs) are synthesized in simple step by hydrothermal carbonization method of natural precursor such as orange juice as a carbon source. Hydrothermal method for synthesized CQDs requires simple and inexpensive equipment and raw materials, thus this method are now common synthesis method. The prepared CQDs have ultrafine size up to few nanometers and several features such as high solubility in water, low toxicity, high biocompatibility, photo-bleaching resistant, Chemical inertness and ease of functionalization which qualifies it for use in many applications such as bio-imaging, photo-labeling and photo-catalysis.
This research demonstrates the
... Show MoreA newly photometric analytical method characterized by its speed and sensitivity was developed for the determination of folic acid in pure and pharmaceutical samples via its oxidation to reddish-orange coloured complex through oxidation by cerium (IV) sulphate in aqua medium using homemade Ayah 3Sx3-3D-solar cell CFI photometer. The colored species were determined using supper bright green light emitting diode (LED) as a source. A 100μl was taken as a best sample volume for the determination of folic acid. The linearity of calibration curve for the instrument response versus folic acid concentration was 0.005-20 mmol.L-1 while the L.O.D. was 0.5 mol.L-1 from the stepwise dilution for the minimum concentration of lowest concentration
... Show MoreThree cohesionless free flowing materials of different density were mixed in an air fluidized bed to study the mixing process by calculating performance of mixing index according to Rose equation (1959) and to study the effect of four variables (air velocity, mixing time, particle size of trace component and concentration of trace component) on the mixing index and as well as on mixing performance. It was found that mixing index increases with increasing the air velocity, mixing time and concentration of trace component until the optimum value. Mixing index depends on the magnitude of difference in particle size The first set of experiments (salt then sand then cast iron) give higher mixing index and better performance of mixing than the
... Show MoreA reliable and environmental analytical method was developed for the direct determination of tetracycline using flow injection analysis (FIA) and batch procedures with spectrophotometric detection. The developed method is based on the reaction between a chromogenic reagent (vanadium (III) solution) and tetracycline at room temperature and in a neutral medium, resulting in the formation of an intense brown product that shows maximum absorption at 395 nm. The analytical conditions were improved by the application of experimental design. The proposed method was successfully used to analyze samples of commercial medications and verified throughout the concentration ranges of 25–250 and 3–25 µg/mL for both FIA and batch procedures, respecti
... Show MoreThe importance of Public Relations activity has increased during the last half of the last century as a specialized and modern administrative function in most institutions. It has, moreover, become an integral part of activities of those institutions of various types, due to its pivotal role in building its reputation and drawing a good mental image among its audiences, as well as its influential and basic role in maintaining communication and the communication between its members at its various levels and their job tasks to ensure the greatest amount of understanding and to enhance trust between them. This is why public relations activity has become indispensable in all institutions, and without it, it is difficult to achieve any coordi
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