SIMULTANEOUS SPECTROPHOTOMETRIC DETERMINATION OF DICLOFENAC SODIUM, PARACETAMOL, AND CHLORZOXAZONE IN TERNARY MIXTURE USING CHEMOMETRIC AND ARTIFICIAL NEURAL NETWORKS TECHNIQUES

  Objective: The aim of this study is to develop and validate simple, accurate, and precise spectrophotometric methods for the simultaneous determination of diclofenac sodium (DIC), paracetamol (PAR), and chlorzoxazone (CHZ) in ternary mixture using chemometric and artificial neural networks (ANN) techniques.Methods: Three chemometric techniques include classical least squares (CLS), principal component regression (PCR), and partial least squares (PLS) in addition to cascade-forward backpropagation ANN (CFBP-ANN) were prepared using the synthetic mixtures containing the three drugs in methanol. In CLS, PCR, and PLS, the absorbances of the synthetic mixtures in the range 267-295 nm with the intervals Δλ=0.2 nm in their zero-order spectra were selected. Then, calibration or regression was obtained using the absorbance data matrix and concentration data matrix for the prediction of the unknown concentrations of DIC, PAR, and CHZ in their mixtures. In CFBP-ANN, two layers, sigmoid layer with 10 neurons and linear layer were found appropriate for the simultaneous determination of the three drugs in their ternary mixture.Results: The four proposed methods were successfully applied to the analysis of the three drugs in laboratory prepared mixtures and tablets with good percentage recoveries in the range of 98-102%. Relative standard deviation for the precision study was found <1%.Conclusion: The four proposed methods showed simplicity, accuracy, precision, and rapidity making them suitable for quality control and routine analysis of the cited drugs in ternary mixtures and pharmaceutical formulation containing them.Â

EFFECT OF DIFFERENT ALKALI CONCENTRATIONS DURING THE REFINING PROCESS ON THE FATTY ACID COMPOSITION OF SUNFLOWER AND SOYBEAN OILS

The effect of NaOH and KOH at concentrations of 12, 14 and 16 Bé° during the refining of sunflower and soybean oils on the fatty acid composition was studied using GLC technique. The quantity of linolenic, linoleic, oleic, palmitic and stearic acid as well as the USFA (unsaturated fatty acids): SFA (saturated fatty acids) ratio were measured. Only slight changes in the quantity of individual fatty acids were found particularly at higher alkali concentrations. The changes in the USFA : SFA ratio compared with crude or semirefined oil were not significant

EFFECT OF DIFFERENT ALKALI CONCENTRATIONS DURING THE REFINING PROCESS ON THE OXIDATIVE STABILITY OF SUNFLOWER AND SOYBEAN OILS

The oxidative stability of bleached soybean and sunflower oils which were previously refined using NaOH and KOH at concentrations of 12, 14 and 16 Béo was studied in comparison with semirefined sunflower and crude soybean oils. Semirefined sunflower oil and crude soybean oil showed the highest stability. Oils previously refined using 12 Béo NaOH or KOH had an acceptable stability. Higher NaOH concentrations resulted in a decrease of stability

Ultra-high frequency, high Q/volume micromechanical resonators in a planar AlN phononic crystal

Citation: Baboly, M. G., Alaie, S., Reinke, C. M., El-Kady, I., & Leseman, Z. C. (2016). Ultra-high frequency, high Q/volume micromechanical resonators in a planar AlN phononic crystal. Journal of Applied Physics, 120(3), 5. doi:10.1063/1.4958671This paper presents the first design and experimental demonstration of an ultrahigh frequency complete phononic crystal (PnC) bandgap aluminum nitride (AlN)/air structure operating in the GHz range. A complete phononic bandgap of this design is used to efficiently and simultaneously confine elastic vibrations in a resonator. The PnC structure is fabricated by etching a square array of air holes in an AlN slab. The fabricated PnC resonator resonates at 1.117 GHz, which corresponds to an out-of-plane mode. The measured bandgap and resonance frequencies are in very good agreement with the eigen-frequency and frequency-domain finite element analyses. As a result, a quality factor/volume of 7.6 x 10(17)/m(3) for the confined resonance mode was obtained that is the largest value reported for this type of PnC resonator to date. These results are an important step forward in achieving possible applications of PnCs for RF communication and signal processing with smaller dimensions. Published by AIP Publishing

EFFECT OF REFINING ON THE PHYSICAL AND CHEMICAL PROPERTIES OF SUNFLOWER AND SOYBEAN OILS

The effect of different refining processes on the physical (colour, specific gravity, refractive index) and chemical (acidity, saponification number, ester number, iodine value, peroxide value, unsaponifiable matter) properties of sunflower and soybean oils was studied. Degumming and dewaxing procedures caused negligible differences in the properties mentioned above. Treatment with NaOH or KOH of 12, 14 and 16 Be⁰ concentration resulted in a reasonable refining loss and residual acidity. Using Na₂C0₃ and NaHC0₃ or KOH and NaOH of higher concentration (over 16 Be⁰) caused high refining losses and unacceptable residual acidity

Evaluation of some phenolic extracts against aphids (Aphis craccivora) Koch under laboratory conditions

Local farmers worldwide have complained in recent years that insect pests have become resistant to the majority of insecticides, owing to pesticide abuse. In addition, highly poisonous and harmful substances may cause health and environmental dangers. Friendly alternatives such as plant extracts are the main targets as substituents to synthetic pesticides. The present study aimed to extract total phenols from some plants and evaluate their efficacy on aphids, Aphis craccivora, under laboratory conditions. Four methanolic plant extracts from Punica granatum, Lantana camara, Portulaca oleracea and Ziziphus jujuba, containing phenolic components were evaluated against A. craccivora through: slide dipping, spraying, and leaf dipping techniques. Generally, positive relationships between the concentrations of the tested phenolic extracts and their mortality percentages were noticed in the case of slide dipping and spraying techniques. Conversely, no biological efficacy was found using the leaf dipping technique. The descending order of effectiveness of the tested extracts depending on their EC50 values was 0.017, 0.321, 1.142 and 16.114 ppm for Z. jujuba, P. oleraceae P. granatum and L. comara, respectively, in the case of the slide dipping technique. In contrast, P. granatum, L. camara, P. oleraceae and Z. jujuba had EC50 values of 0.0023, 0.017, 0.321 and 2.3409 ppm, respectively, in the case of the spraying technique. Additionally, a direct proportion was found between mortality percentages and treatment period for plant extracts under study with both techniques. After formulation and completion of additional essential field research, phenols isolated from the plants under study could be employed to combat A. craccivora

Molecular characterization of cytochrome P450 1B1 and effect of benzo(a) pyrene on its expression in Nile tilapia (Oreochromis niloticus)

Cytochrome P4501 (CYP1) family enzymes are most active in hydroxylating a variety of environmental contaminants including Polyaromatic Hydrocarbons (PAH), planar polychlorinated biphenyls and arylamines. CYP1B which belongs to the cytochrome  P450 superfamily of genes, is involved in the oxidation of endogenous and exogenous compounds, and could potentially be a useful biomarker in fish for exposure to arylhydrocarbon receptors (AhR) ligands. In this study, a new complementary   DNA (cDNA) of the CYP1B subfamily encoding 1B1 was isolated from Nile tilapia (Oreochromis niloticus) liver after intracoelomic injection with benzo (a) pyrene (BaP). The full-length cDNA was 2107 base pair (bp) long and contained a 5' noncoding region of 29 bp, an open reading frame of 1527 bp coding for 508 amino acids and a stop codon, and a 3' noncoding region of 551 bp, respectively. The deduced amino acid sequence of Nile tilapia CYP1B1 shows similarities of 79.7, 70.3, 65.7, 65.4, 65.0, and 63.7% with Plaice CYP1B1, Japanese eel CYP1B1, zebra fish CYP1B1, common carp CYP1B1, common carp CYP1B2 and  Channel catfish CYP1B1, respectively. The phylogenetic tree based on the amino acid sequences clearly shows tilapia CYP1B1  and Plaice CYP1B1 to be more closely related to each other than to the other CYP1B subfamilies. Furthermore, real-time PCR  was used for measuring BaP induction of CYP1B1 mRNA in different organs of tilapia (O. niloticus), using β-actin gene as internal control, and the results revealed that there was a large increase in CYP1B1 mRNA in liver (22.8), intestine (2.0) and muscles (1.3).Keywords: Oreochromis niloticus, benzo (a) pyrene, CYP1B1 cDNA, sequence analysis, real-time PCR

Demonstration of acoustic waveguiding and tight bending in phononic crystals

Citation: Baboly, M. G., Raza, A., Brady, J., Reinke, C. M., Leseman, Z. C., & El-Kady, I. (2016). Demonstration of acoustic waveguiding and tight bending in phononic crystals. Applied Physics Letters, 109(18), 4. doi:10.1063/1.4966463The systematic design, fabrication, and characterization of an isolated, single-mode, 90 degrees bend phononic crystal (PnC) waveguide are presented. A PnC consisting of a 2D square array of circular air holes in an aluminum substrate is used, and waveguides are created by introducing a line defect in the PnC lattice. A high transmission coefficient is observed (-1 dB) for the straight sections of the waveguide, and an overall 2.3 dB transmission loss is observed (a transmission coefficient of 76%) for the 90 degrees bend. Further optimization of the structure may yield higher transmission efficiencies. This manuscript shows the complete design process for an engineered 90 degrees bend PnC waveguide from inception to experimental demonstration. Published by AIP Publishing

Transmission Studies of Left-handed Materials

Left-handed materials are studied numerically using an improved version of the transfer-matrix method. The transmission, reflection, the phase of the reflection and the absorption are calculated and compared with experiments for both single split-ring resonators (SRR) with negative permeability and left-handed materials (LHMs) which have both the permittivity and permeability negative. Our results suggest ways of positively identifying materials that have both permittivity and permeability negative, from materials that have either permeability or permittivity negative

A review of size and geometrical factors influencing resonant frequencies in metamaterials

Although metamaterials and so-called left-handed media have originated from theoretical considerations, it is only by their practical fabrication and the measurement of their properties that they have gained credibility and can fulfil the potential of their predicted properties. In this review we consider some of the more generally applicable fabrication methods and changes in geometry as they have progressed, exhibiting resonant frequencies ranging from radio waves to the visible optical region