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A Real-coded Genetic Algorithm has been used to develop a new correlation to estimate the enthalpy of vaporization for pure compounds and petroleum fractions as a function of the normal boiling point and specific gravity. In developing the correlation 80% of the data was used and the remaining are used for validation. The results of the proposed correlations are compared to others in literature. The comparison indicates that the proposed model is simple to use and more accurate than the most common correlations for predicting the enthalpy of vaporization of pure compounds and petroleum fractions.  相似文献   
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The objective of this study was to evaluate the effect of sample presentation (tissue type) and maturity (ripe and unripe) on the classification of banana (Musa Cavendish) samples sourced from two different geographical regions and analysed using mid infrared (MIR) spectroscopy. The coefficient of determination (R2) and the standard error of cross-validation (SECV) obtained using partial least squares discriminant analysis were 0.83 (0.33), 0.75 (0.25) and 0.94 (0.19) for the prediction of maturity, geographical origin and tissue type, respectively. No effect of either of type of tissue (e.g. pulp or peel) or maturity was observed. The results of this study demonstrated that MIR spectroscopy might be used to classify the origin of the banana samples at different degrees of ripeness. However, one of the limitations of this study is on the number of samples analysed and further validation must be recommended using samples from other sources, regions and harvest seasons.  相似文献   
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A novel quinazoline derivative, 3-cyclopropyl-3,4-dihydroquinoline-2(1H)-One (CPHQ), was successfully designed and synthesized. Then, its corrosion inhibition behavior on carbon steel (CS) surface in 1.0?M HCl at different temperatures was investigated using chemical, electrochemical and theoretical techniques. The experiments confirmed that the studied inhibitor shows inhibition efficiency as high as 95% even at very low concentration of 5?×?10?3 M. To ascertain the nature of adsorption of CPHQ molecules on CS surface, Langmuir adsorption isotherm model was best fitted. From potentiodynamic polarization (PDP) calculations, it was concluded that the CPHQ acted as a mixed type corrosion inhibitor. Electrochemical impedance spectroscopy (EIS) studies revealed that increase in CPHQ concentration, resulted in an increase in the polarization resistance with a simultaneous decrease in the double-layer capacitance values. PDP tests were also performed to understand the corrosion behavior of CS as a function of temperature without and with varying concentrations of CPHQ, at temperatures 303, 313, 323, and 333?K. It can be concluded that the corrosion inhibition effect was dependent on the concentration of the inhibitor and the solution temperature. In order to understand the basic insights of the action mode of CPHQ molecules, Density Functional Theory (DFT) method, and Molecular Dynamic (MD) simulations were also employed on the optimized structure of CPHQ.  相似文献   
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A cartographic-oriented model uses algebraic map operations to perform spatial analysis of medical data relative to the human body. A prototype system uses 3D visualization techniques to deliver analysis results. A prototype implementation suggests the model might provide the basis for a medical application tool that introduces new information insight.  相似文献   
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Changes in bacterial counts on beef carcasses at specific points during slaughter and fabrication were determined, and the effectiveness of nisin, lactic acid, and a combination of the lactic acid and nisin in reducing levels of microbiological contamination was assessed. Swab samples were obtained from the surfaces of randomly selected beef carcasses. Carcasses were swabbed from the neck, brisket, and renal site after skinning, splitting, and washing. Treatments involving lactic acid (1.5%), nisin (500 IU/ml), or a mixture of nisin and lactic acid were applied after the neck area was washed. A control group was not sprayed. Results indicated that the highest prevalence of aerobic plate counts (APCs), total coliforms, and Escherichia coli was found in the neck site after splitting, and the lowest level of microbial contamination was found after skinning. Washing with water did not significantly reduce the bacterial load. The largest reduction in APCs, total coliforms, and E. coli occurred on carcasses treated with a mixture of nisin and lactic acid. A mixture of nisin and lactic acid can be applied to beef carcasses through spray washing and can reduce bacterial populations by 2 log units.  相似文献   
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Because propolis contains many types of antioxidant compounds such as polyphenols and flavonoids, it can be useful in preventing oxidative damages. Ethyl acetate extracts of propolis from several Algerian regions show high activity by scavenging free radicals, preventing lipid peroxidation and inhibiting myeloperoxidase (MPO). By fractioning and assaying ethyl acetate extracts, it was observed that both polyphenols and flavonoids contribute to these activities. A correlation was observed between the polyphenol content and the MPO inhibition. However, it seems that kaempferol, a flavonoid, contributes mainly to the MPO inhibition. This molecule is in a high amount in the ethyl acetate extract and demonstrates the best efficiency towards the enzyme with an inhibiting concentration at 50% of 4 ± 2 μM.  相似文献   
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