Hydrogen peroxide was determined by a new , accurate , sensitive and rapid method via continuous mode of FIA coupled with total luminescence measurement which include the chemiluminescence generated ,based on the oxidation of Luminol which is loaded on poly acrylic acid gel beads by hydrogen peroxide in presence of Cobalt (II) ion as a chemiluminescence catalyst and the fluorescence that was created by the insitu radiation of the released chemiluminescence light. Fluorescien molecule was used as an accepter fluorophore where it is irradiated internally and instantly by the generation of luminol chemiluminescence light as internal source for irradiation of fluorescien molecule (Fluorescence Energy Transfer (FRET) ) . It can easily give fluorescence light (i.e , no external source for irradiation is used ) at λmax =530 nm. The method is based on the absorbance of the donor molecule (Luminol) by fourteen poly acrylic acid gel beads located in specially designed cell, this cell will measure instantly the emitted light (FRET) . A sample volume of 80 μL was used throughout the whole work. Linear calibration curve extend from 0.1 - 100 μMol .L-1 , with correlation coefficient of 0.9985 and limit of detection L.O.D (S/N =3) 217.60 pg/sample using step wise dilution of the minimum concentration that was achieved by the calibration graph. Repeatability (RSD%) of less than 0.5% for six successive measurement of 50 μMol .L-1 of hydrogen peroxide. The method was applied successively in determination of hydrogen peroxide in some pharmaceutical disinfectants
Citrate-gel auto combustion technique was used to synthesize nickel-copper mixed ferrite nanoparticles NixCu1-xFe2O4 (x= 0.0, 0.4, 1.0) with different calcinating temperatures (200, 450, 650 and 850 °C). Structural, morphological, magnetic, and electrical properties were studied using X-ray diffraction (XRD), transmission electron microscopy (TEM), field emission scanning electron microscopy (FE-SEM), Fourier transform infrared spectroscopy (FTIR), vibrating sample magnetometer (VSM), and LCR meter in order to determine significant influences of Cu2+ cations content in nickel ferrite. The XRD patterns showed that all compositions had cubic spinels, except CuFe2O4
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In the present work, leaching process studiedusing organic acids (acetic acid and lactic acid) to extract phosphate from the Iraqi Akashat phosphate ore by separation of calcareous materials (mainly calcite). This approach characterized by energy conservation, environmental enhancement by recovery of calcite as calcium sulfate (gypsum), keeping the physical and chemical properties of apatite. Samples were analyzed using X-ray diffraction and FTIR spectrophotometer. From the obtained experimental data it was found that using the two organic acids yields closed purity values of the produced apatite at the optimum conditions, while at different acid concentrations, it was found that the efficiency of acetic acid is higher at the low acid co
... Show MoreIn this paper, we study the impact of the variable rotation and different variable on mixed convection peristaltic flow of incompressible viscoplastic fluid. This is investigated in two dimensional asymmetric channel, such as the density, viscosity, rate flow, Grashof number, Bingham number, Brinkman number and tapered, on the mixed convection heat transfer analysis for the peristaltic transport of viscoplastic fluid with consideration small Reynolds number and long wavelength, peristaltic transport in asymmetric channel tapered horizontal channel and non-uniform boundary walls to possess different amplitude wave and phases. Perturbation technique is used to get series solutions. The effects of different values of these parame
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Abstract In this study, an investigation is conducted to realise the possibility of organic materials use in radio frequency (RF) electronics for RF-energy harvesting. Iraqi palm tree remnants mixed with nickel oxide nanoparticles hosted in polyethylene, INP substrates, is proposed for this study. Moreover, a metamaterial (MTM) antenna is printed on the created INP substrate of 0.8 mm thickness using silver nanoparticles conductive ink. The fabricated antenna performances are instigated numerically than validated experimentally in terms of S11 spectra and radiation patterns. It is found that the proposed antenna shows an ultra-wide band matching bandwidth to cover the frequencies from 2.4 to 10 GHz with bore-sight gain variation from 2.2 to
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The 3-parameter Weibull distribution is used as a model for failure since this distribution is proper when the failure rate somewhat high in starting operation and these rates will be decreased with increasing time .
In practical side a comparison was made between (Shrinkage and Maximum likelihood) Estimators for parameter and reliability function using simulation , we conclude that the Shrinkage estimators for parameters are better than maximum likelihood estimators but the maximum likelihood estimator for reliability function is the better using statistical measures (MAPE)and (MSE) and for different sample sizes.
Note:- ns : small sample ; nm=median sample
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In situ gel can be defined as a polymer solution administered as a liquid and when exposed to some physiologic condition such as thepH, ionic, temperature modulation or solvent and UV induced gelation undergo to phase transition to a semisolid gel. Ketotifenfumarate belongs to the histamine H1 receptor antagonists, and Ketotifen fumarate is used in the treatment of allergic conditions likeconjunctivitis and rhinitis. This work aims to study the natural polymer effects (xanthan gum,gellan gum) on the properties of pH-trigger in situ ocular gel, then compared the drug-releasing rate of optimized formula with the market ketotifen eye drop. Eightformulations (F1-F8) were prepared using different concentrations of xanthan gum, gellan gum with ca
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Background/objectives: To study the motion equation under all perturbations effect for Low Earth Orbit (LEO) satellite. Predicting a satellite’s orbit is an important part of mission exploration. Methodology: Using 4th order Runge–Kutta’s method this equation was integrated numerically. In this study, the accurate perturbed value of orbital elements was calculated by using sub-steps number m during one revolution, also different step numbers nnn during 400 revolutions. The predication algorithm was applied and orbital elements changing were analyzed. The satellite in LEO influences by drag more than other perturbations regardless nnn through semi-major axis and eccentricity reducing. Findings and novelty/improvement: The results demo
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The effect of using different R -molar ratio under variable reaction conditions (acidic as well as basic environment and reaction temperature) have been studied. The overall experiments are driven with open and closed systems. The study shows that there is an optimum value for a minimum gelling time at R equal 2. The gelling time for all studied open system found to be shorter than in closed system. In acidic environment and when R value increased from 2 to 10, the gelling time of closed systems has increased four times than open systems at T=30 ?C and fourteen times when temperature reaction increased to 60 ?C. While in basic environment the influence of increasing R value was limited.
In this study, the development of an indirect spectrophotometric method for the determination of folic acid in pure and pharmaceutical preparations is described. The method is based on the oxidation of pyrocatechol with iron (III) in an acidic medium, followed by the reaction with folic acid (FA) to produce a stable, water-soluble orange compound with maximum absorption at 350 nm versus the blank reagent. The complex of charge transfer was studied under optimal conditions; the titration graph was linear over the range of 0.5-25 μg/mL with a relative error of 1.2-2.8 and a relative standard deviation of 2.43-1.45 depending on the concentration level.