In this work, the effects of size, and temperature on the linear and nonlinear optical properties in InGaN/GaN inverse parabolic and triangular quantum wells (IPQW and ITQW) for different concentrations at the well center were theoretically investigated. The indium concentrations at the barriers were fixed to be always xmax = 0.2. The energy levels and their associated wave functions are computed within the effective mass approximation. The expressions of optical properties are obtained analytically by using the compact density-matrix approach. The linear, nonlinear, and total absorption coefficients depending on the In concentrations at the well center are investigated as a function of the incident photon energy for different values of temperature and quantum wells size. The results show that the In concentrations, size and temperature have a significant effect on these optical properties. The positions of the resonance peaks of the absorption coefficients were blue-shifted under increasing indium compositions in the quantum wells (InGaN) and temperature while they were red-shifted with the increase in the thickness of the wells. Moreover, the amplitudes of the resonance peaks were enhanced under the increase of the In composition, the temperature, and the thickness of the quantum wells. The optical absorption in ITQW structure is slightly greater than that in IPQW one.
A modern, rapid RP-HPLC-UV method was developed and validated in compliance with FDA and EMA guidelines for simultaneous quantification of 15 βlactam antibiotics) Ampicillin, Amoxicillin, cephalexin, cefotaxime, cefoxitin, cefamandole, cephalothin, piperacillin, penicillin, oxacillin, cloxacillin, nafcillin Carbenicillin, Mezlocillin and Dicloxacillin) in pharmaceutical formulations and pure forms. The method employs Column NEUCLEODUR C-18 (4.0 mm x 100 mm, 5µm particle size), at a temperature of thirty degrees Celsius, and the mobile phase was acetonitrile and KH2PO4 using gradient elution with a total separation time of 13 minutes, a flow rate of 1.3 ml/min, at = pH 4.5 for the buffer solution and the λ max was 220 nm. The met
... Show MoreBackground: The main purpose of this study is to find if there is any correlation between the level of C-reactive protein (CRP) in gingival crevicular fluid with its serum level in chronic periodontitis patients and to explore the differences between them according to the probing depth. Materials and methods: Forty seven male subjects enrolled in this study. Thirty males with chronic periodontitis considered as study group whom further subdivided according to probing depth into subgroup 1 with pocket depth ≤6mm, subgroup 2 with pocket depth >6mm. The other 17 subjects considered as controls. For all subjects, clinical examination where done for periodontal parameters plaque index (PLI), gingival index (GI), bleeding on probing (BOP),
... Show MoreThe simple and available technique of colorimetry and indirect X-ray fluorescence determination of tetracycline hydrochloride (in the form of colored complex with iron(III) ions) and cyanocobalamine (in the form of the colored thiocyanate complex with cobalt(II) ions) is offered. The analytes were separated from the accompanying components by sorption to polyurethane foam based on ethers. The conditions of sorption separation and measurement of analytical signal of these substances are optimized. The obtained results of tetracycline drugs and injection solution B12 vitamin are in satisfactory agreement with data declared by the manufacturer.
This study is an attempt to investigate the semantic and syntactic features of English and Arabic verbs of eating. After surveying the literature on the meaning of verbs in both languages, three chapters address the major issues in this subject. The problem to be investigated in this study can be summarized in the following points: 1. The overlapping of semantic and syntactic features within the category of verbs of eating in English and Arabic. 2. Which semantic classification is more accurate and through which method? 3. Which classification, the semantic or the syntactic, is more important? This study hypothesized the following: 1. The semantic features are more influential in analyzing the category of verbs of eating than the syntactic
... Show MoreIntroduction: The bacteriological and histopathological study of Raoultella planticola in local rabbits is not presented in previous research. There is no specific information about studying this bacterium in local rabbits. Hypothesis: The present study was based on Bacteriological and Histopathological changes in the trachea and lung of local rabbits after Samples were collected from 50 unhealthy animals that appear to be suffering from respiratory signs. Aim: To study the bacteria that were isolated for the first time from sheep suffering from respiratory infections, and diagnose them through Vitk2. Methods: We injected them into a group of local rabbits and studied the histopathological changes in the trachea and lungs. d
... Show MoreA simple, economic, rapid, reliable, and stability-indicating high-performance liquid chromatography (HPLC) method has been developed and validated for the simultaneous determination of paracetamol (PCM) and caffeine (CF) in solid dosage form. The chromatographic separations were achieved with a Waters Symmetry® C18 column (5 μm, 4.6 × 150 mm), using a mixture of methanol and water (40:60, v/v) as a mobile phase, under isocratic elution mode with a flow rate of 0.8 mL/min, and ultraviolet (UV) detection was set at 264 nm. The oven temperature for the column was set and maintained at 35 °C. The method was validated according to International Conference on Harmonization (ICH) guidelines, and it demonstrated excellent linearity, wi
... Show MoreOne common heavy metal that is extremely harmful to the kidneys, reproductive system, and nervous system of humans is lead (Pb). This study aimed to investigate the effectiveness of a novel nanocomposite adsorbent, synthesised from polypyrrole, zinc oxide, and nickel (PPy/ZnO-NiO), in eliminating Pb(II) ions from a waterbased solution. This adsorbent offers excellent metal selectivity, environmental stability, ease of manufacture, and reusability. Several techniques, namely XRD, FTIR, TGA, SEM, TEM, EDX, and BET, were employed to characterize the synthesised nanocomposite adsorbent. The study examined the impact of multiple factors influencing the adsorption process, including pH, temperature, contact period, metal ion concentration, and ad
... Show More<p><strong>Objective: </strong>The aim of our study was to compare between flavonoids and phenolic acids contents of leaves and fruits of <em>Melia azedarach</em> since no phytochemical investigation had done previously in Iraq.</p><p><strong>Methods: </strong>The leaves and fruits of <em>Melia azedarach </em>were extracted by soxhlet using 80% ethanol then the dried extract was suspended in water and fractionated using petroleum ether, chloroform, ethyl acetate, and n-butanol. The n-butanol fraction was hydrolyzed by acid and partitioned with ethyl acetate. The different fractions containing flavonoids and phenolic acids were analyzed by HPLC and HPTLC.</p><
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