This work dealt with separation of naphthenic hydrocarbons from non-naphthenic hydrocarbons and in particular concerns an improved process for increasing the naphthenes concentration in naphtha, The separation was examined using adsorption by Y and B zeolite in a fixed bed process. The concentration of naphthenes in the influent and effluent streams was determined using PONA classification. The effect of different operating variables such as feed flow rate (2- 4 L/hr); bed length (50 - 80 cm) on the adsorption capacity of Y and zeolite was studied. Increasing the bed length lead to increase the naphthenes concentration, and increasing the flow rate lead to decrease in the concentration of naphthenes, It was found that the decrease in flow rate to 2 L/hr and increase the bed length to 80 cm lead to increase the naphthenes concentration from 6.2 to 24.8 Wt. %.
Resumen
Este trabajo de investigación ofrece uno de los temas relevantes en la lengua, el cual es estudiar las dimensiones sintácticas, semánticas y pragmáticas de las preposiciones, en general, y de las dos preposiciones "Para" y "Por" en concreto, en una unidad linguística más amplia que la llamada "Oración". En la parte referida al estudio de las dos preposiciones mencionadas, estudiamos sus distntos usos funcionales, usos que se acercan, unas veces, entre sí y se alejan en otras.
Abstract
... Show MoreRESUMEN:
Pretendemos hacer con este trabajo un breve recorrido sobre lo que han dicho algunos gramáticos de las construcciones condicionales, a la par señalaremos los criterios que los mismos establecen y siguen para diferenciar entre distintos tipos de estructuras condicionales o entre las construcciones que ellos entienden o consideran como tales y las que no, atendiendo fundamentalmente a dos criterios; formal y semántico-pragmático. El presente trabajo tiene como objetivo la clasificación y la descripción de las construcciones condicionales, demostrando que no todas las condicionales son hipotéticas ni todas las hipotéticas son condicionales.
Abstract
We intend to make this work
... Show MoreIodine-doped polythiophene thin films are prepared by aerosol assisted plasma jet polymerization at atmospheric pressure and room temperature. The doping of iodine was carried out in situ by employing iodine crystals in thiophene monomer by weight mixing ratios of 1%, 3%, 5% and 7%. The chemical composition analyses of pure and iodine-doped and heat-treated polythiophene thin films are carried out by FTIR spectroscopy studies. The optical band gaps of the films are evaluated from absorption spectrum studies. Direct transition energy gaps are determined from Tauc plots. The structural changes of polythiophene upon doping and the reduction of optical band gap are explained on the basis of the results obtained from FTIR spectroscopy, UV–V
... Show MoreBackground: In type 2 diabetes mellitus there is a progressive loss of beta cell function. One new
approach yielding promising results is the use of the orally active dipeptidyl peptidase-4 (DPP-4)
inhibitors for type 2 diabetes mellitus.
Objective: This study aims at comparing the possible occurrence of macrovascular & microvascular
complications in Iraqis patients with type 2 diabetes mellitus using two combinations of drugs
metformin + glibenclamide and metformin + sitagliptin.
Methodology: Sixty eight T2DM patients and 34 normal healthy individuals as control group were
enrolled in this study and categorized in to two treatment groups. The group 1 (34 patients ) received
metformin 500 mg three times daily
Pectin is available in many plants and in this study, the peels of tomatoes and beet were used to be an economical source of pectin production instead of dumping it with waste or using it as animal feed. The pectin extracted from the peels using different solutions, namely citric acid (2 M), oxalic acid (2%) and hydrochloric acid (0.5 M) the outcome of the extraction methods, 7. 1%, 6% and 11% respectively for tomatoes peels, while the pectin of beet peels were 8%, 6.5%, and 8.3%, and the highest percentage obtained in the manner of hydrochloric acid adopted in the manufacture of yogurt.Yogurt was manufactured with four treatments, in the first treatment standard pectin was added and the second treatment in addition to the pectin extracted
... Show MoreCoupling reaction of 4-nitroaniline with 3-aminobenzoic acid provided the corresponding bidentate azo ligand. The prepared ligand was identified by Microelemental Analysis, 1H-NMR, FT-IR, and UV-Vis spectroscopic techniques. Treatment of the prepared ligand with Y(III) and La(III) metal ions in 1:3 M:L ratio in aqueous ethanol at optimum pH yielded a series of neutral complexes with the general formula of [M(L)3]. The prepared complexes were characterized by flame atomic absorption, Elemental Analysis (C, H, N), FT-IR, and UV-Vis spectroscopic methods, as well as conductivity measurements. The nature of the complexes formed were studied following the mole ratio and continuous variation methods; Beer's law obeyed over a concentration range o
... Show MoreWe studied in this research how to find a method of estimating the quantity (Kinetically) of three kinds of Insecticide and their mixture, which are used in agriculture. The extracted insecticide from the polluted samples with these insect from air, soil, and the leaves of trees, have be used into the reaction with H2O2 and benzedine. The kinetic study of this reaction was formed in basic medium,( pH= 8.6), using UV. Spectra at (?= 420nm). The study showed that the reaction is the first order, and the speed of the reaction was used to estimate the concentration of insecticide in solution and mixture. The experiments of this study indicated that this method has the speed and efficiency for quantitatively estimating these
... Show MoreTwo simple methods spectrophotometric were suggested for the determination of Cefixime (CFX) in pure form and pharmaceutical preparation. The first method is based without cloud point (CPE) on diazotization of the Cefixime drug by sodium nitrite at 5Cº followed by coupling with ortho nitro phenol in basic medium to form orange colour. The product was stabilized and measured 400 nm. Beer’s law was obeyed in the concentration range of (10-160) μg∙mL-1 Sandell’s sensitivity was 0.0888μg∙cm-1, the detection limit was 0.07896μg∙mL-1, and the limit of Quantitation was 0.085389μg∙mL-1.The second method was cloud point extraction (CPE) with using Trtion X-114 as surfactant. Beer
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