Esterification considers the most important reaction in biodiesel production. In this study, oleic acid was used as a suggested feedstock in order to study and simulate production of biodiesel. The batch esterification reaction of oleic acid was carried out at various operating conditions; temperature from 40 to 70 °C, ethanol to oleic acid molar ratio from 3/1 and 6/1 and a reaction time up to 180 min.
The catalyst used was prepared NaY zeolite, which is added to the reaction mixture as 2, 5 and 10 wt.% of oleic acid.
The results show that the optimum conditions, gives 0.81 conversion of oleic acid, were 6/1 molar ratio of ethanol/oleic acid, 5 wt.% NaY relative to initial oleic acid, 70°C and 60 minutes. The activation energy of the suggested model was 42692 J/mole for forward reaction and 17218 J/mole for backward reaction.
A linear engine generator with a compact double-acting free piston mechanism allows for full integration of the combustion engine and generator, which provides an alternative chemical-to-electrical energy converter with a higher volumetric power density for the electrification of automobiles, trains, and ships. This paper aims to analyse the performance of the integrated engine with alternative permanent magnet linear tubular electrical machine topologies using a coupled dynamic model in Siemens Simcenter software. Two types of alternative generator configurations are compared, namely long translator-short stator and short translator-long stator linear machines. The dynamic models of the linear engine and linear generator, validated
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Background: Simvastatin (SIM) is a lipid-lowering agent to prevent disorders caused by clogged blood vessels. Because of its low solubility, it has low bioavailability. The adsorption technique is effective in improving drug solubility and dissolution rate. Objective: To use magnesium aluminum silicate (MAS) as an adsorbent in combination with Soluplus® as a hydrophilic polymer to formulate SIM as immediate-release tablets (IRTs). Methods: We used the solvent evaporation method to make MAS-loaded SIM in the presence of Soluplus®, making sure that the ratio of SIM to MAS to SOLU was 1:6:3. We then used this mixture to make IRTs. Using the direct compression method, we made all of the SIM-IRT formulas. We used diluents like Avicel
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A new method for determination of allopurinol in microgram level depending on its ability to reduce the yellow absorption spectrum of (I-3) at maximum wavelength ( ?max 350nm) . The optimum conditions such as "concentration of reactant materials , time of sitting and order of addition were studied to get a high sensitivity ( ? = 27229 l.mole-1.cm-1) sandal sensitivity : 0.0053 µg cm-2 ,with wide range of calibration curve ( 1 – 9 µg.ml-1 ) good stability (more then24 hr.) and repeatability ( RSD % : 2.1 -2.6 % ) , the Recovery % : ( 98.17 – 100.5 % ) , the Erel % ( 0.50 -1.83 % ) and the interference's of Xanthine , Cystein , Creatinine , Urea and the Glucose in 20 , 40 , 60 fold of analyate were also studied .
Water one of the most important sources Which is no doubt essential for life surviving, water is vital in many sectors of life e.g. ( agriculture, industrial, power and so many things can’t be restricted on the mentioned items, water has become major problem facing the world today. Competition over water resources between nations has made it as a vital commodity and a justification for waging wars against its neighbor’s countries, there are currently 263 rivers that either cross or demarcate international political boundaries. Geographically, Europe has the largest number of international basins (69), followed by Africa (59), Asia (57), North America (40), and South America (38).The absolute numbers of international basins, as well as t
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Groupwise non-rigid image alignment is a difficult non-linear optimization problem involving many parameters and often large datasets. Previous methods have explored various metrics and optimization strategies. Good results have been previously achieved with simple metrics, requiring complex optimization, often with many unintuitive parameters that require careful tuning for each dataset. In this chapter, the problem is restructured to use a simpler, iterative optimization algorithm, with very few free parameters. The warps are refined using an iterative Levenberg-Marquardt minimization to the mean, based on updating the locations of a small number of points and incorporating a stiffness constraint. This optimization approach is eff
... Show MoreThree azo compounds were synthesized in two different methods, and characterized by FT-IR, HNMR andVis) spectra, melting points were determined. The inhibitory effects of prepared compounds on the activity of human serum cholinesterase have been studied in vitro. Different concentrations of study the type of inhibition. The results form line weaver-Burk plot indicated that the inhibitor type was noncompetitive with a range (33.12-78.99%).
the effecth of some chemicals on growth of two azotobacter chroococcum and aniline caused significant increase of growth