A liquid membrane process of Alkaloids extraction from Datura Innoxia solution was studied applying pertraction process in rotating discs contactor (RDC). Decane as a liquid membrane and dilute sulphuric acid as stripping solution were used. The effect of the fundamental parameters influencing the transport process, eg type of solvent used, effect of disks speed, amount of liquid membrane and effect of pH for feed and strip solution. The transport of alkaloids was analysed on the basis of kinetic laws of two consecutive irreversible first order reactions. Thus, the kinetic parameters (k1, k1,, tmax, and) for the transport of alkaloids were determined. The effect of organic membrane type on percentage of Alkaloids transport was found to be in the order (n-decane> n-heptane> n-hexane> ethyl ether). The results showed that the highest alkaloids extraction was obtained when using two stages,(10 rpm) discs speed,(pH= 9.5) of feed solution and (pH= 2) of acceptor solution in n-decane. Observation showed that the membrane entrance rate constant k1 and percentage of alkaloids transported in strip phase increased with increasing numbers of stages but the exit rate constant k2 decreased. The alkaloids extraction ratio increased with increasing the disks speed from 5 to 10 rpm but decreased at 15 rpm and decreased when increasing the volume of membrane. Also pH of feed and strip solution affected the extraction ratio and rate constants.
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The process of accurate localization of the basic components of human faces (i.e., eyebrows, eyes, nose, mouth, etc.) from images is an important step in face processing techniques like face tracking, facial expression recognition or face recognition. However, it is a challenging task due to the variations in scale, orientation, pose, facial expressions, partial occlusions and lighting conditions. In the current paper, a scheme includes the method of three-hierarchal stages for facial components extraction is presented; it works regardless of illumination variance. Adaptive linear contrast enhancement methods like gamma correction and contrast stretching are used to simulate the variance in light condition among images. As testing material
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<span>One of the main difficulties facing the certified documents documentary archiving system is checking the stamps system, but, that stamps may be contains complex background and surrounded by unwanted data. Therefore, the main objective of this paper is to isolate background and to remove noise that may be surrounded stamp. Our proposed method comprises of four phases, firstly, we apply k-means algorithm for clustering stamp image into a number of clusters and merged them using ISODATA algorithm. Secondly, we compute mean and standard deviation for each remaining cluster to isolate background cluster from stamp cluster. Thirdly, a region growing algorithm is applied to segment the image and then choosing the connected regi
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Production of the steroidal saponin digitonin in multiplied shoots of Digitalis purpurea , (var. Excelsior Mixed) has been achieved in vitro by two experiments. In the experiment 1, shoot tips ( 1cm length ) explants from the sterilized seedlings were excised and cultured on MS medium ( Murashige and Skoog medium) supplemented with 0.5 mg/L TDZ (thidiazuron) and cholesterol at the concentrations 0.0, 0.1, 0.3, 0.5, 1.0, 1.5, 2.0 or 4.0 mg/L. After 45 day, results showed that the treatment with 0.5 mg/L TDZ and 2.0mg/L cholesterol had a positive effected on increasing the dry weight of multiplied shoots and their production of digitonin when compared with other treatments, where this treatment gave 2
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