The Experts below are selected from a list of 6 Experts worldwide ranked by ideXlab platform
Yoram Cohen - One of the best experts on this subject based on the ideXlab platform.
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Morphometric characterization of calcium sulfate dihydrate (gypsum) scale on reverse osmosis membranes
Journal of Membrane Science, 2005Co-Authors: Wen-yi Shih, Anditya Rahardianto, Ron-wai Lee, Yoram CohenAbstract:The axial development of calcium sulfate dihydrate (gypsum) scaling on selected reverse osmosis (RO) membrane surfaces was investigated experimentally in a plate-and-frame RO system. Scaling experiments with model solutions demonstrated progressive axial development of surface gypsum Crystals along the membrane surface. The impact of surface Crystallization was characterized via flux decline measurements and by both optical and high-resolution scanning electron microscopy (SEM) surface imaging. Surface coverage by gypsum scale (percent area covered and gypsum surface mass density) increased along the membranes (towards the membrane exit), consistent with the increase in concentration polarization. At the membrane channel entry, surface gypsum Crystals were at their initial growth stage formed as primarily needle-like structures. With increasing axial distance from the entry, surface Crystallization resulted in Crystal structures that transitioned from the needle and plate-like structures, in the submicron size range, to partial Rosettes to complete Rosette structures in the mm size range. Significant differences were observed in the extent of surface scale coverage and surface Crystal size among the membrane studied. Antiscalant addition to the feed solution led to progressive decline in the percent of area covered by scale with increasing antiscalant dosage and corresponding decrease in flux decline. Antiscalant addition resulted in perturbed surface Crystal morphology of flattened and/or fused Rosette Crystal arms and to complete elimination of surface Crystals at a sufficiently high antiscalant dosage. The present study demonstrates that gypsum scale development is affected by the formation of surface Crystals on the membrane surface, thereby suggesting that there is merit to expanded research on the direct impact of surface topology and chemistry on surface Crystallization of mineral salts.
Wen-yi Shih - One of the best experts on this subject based on the ideXlab platform.
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Morphometric characterization of calcium sulfate dihydrate (gypsum) scale on reverse osmosis membranes
Journal of Membrane Science, 2005Co-Authors: Wen-yi Shih, Anditya Rahardianto, Ron-wai Lee, Yoram CohenAbstract:The axial development of calcium sulfate dihydrate (gypsum) scaling on selected reverse osmosis (RO) membrane surfaces was investigated experimentally in a plate-and-frame RO system. Scaling experiments with model solutions demonstrated progressive axial development of surface gypsum Crystals along the membrane surface. The impact of surface Crystallization was characterized via flux decline measurements and by both optical and high-resolution scanning electron microscopy (SEM) surface imaging. Surface coverage by gypsum scale (percent area covered and gypsum surface mass density) increased along the membranes (towards the membrane exit), consistent with the increase in concentration polarization. At the membrane channel entry, surface gypsum Crystals were at their initial growth stage formed as primarily needle-like structures. With increasing axial distance from the entry, surface Crystallization resulted in Crystal structures that transitioned from the needle and plate-like structures, in the submicron size range, to partial Rosettes to complete Rosette structures in the mm size range. Significant differences were observed in the extent of surface scale coverage and surface Crystal size among the membrane studied. Antiscalant addition to the feed solution led to progressive decline in the percent of area covered by scale with increasing antiscalant dosage and corresponding decrease in flux decline. Antiscalant addition resulted in perturbed surface Crystal morphology of flattened and/or fused Rosette Crystal arms and to complete elimination of surface Crystals at a sufficiently high antiscalant dosage. The present study demonstrates that gypsum scale development is affected by the formation of surface Crystals on the membrane surface, thereby suggesting that there is merit to expanded research on the direct impact of surface topology and chemistry on surface Crystallization of mineral salts.
Anditya Rahardianto - One of the best experts on this subject based on the ideXlab platform.
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Morphometric characterization of calcium sulfate dihydrate (gypsum) scale on reverse osmosis membranes
Journal of Membrane Science, 2005Co-Authors: Wen-yi Shih, Anditya Rahardianto, Ron-wai Lee, Yoram CohenAbstract:The axial development of calcium sulfate dihydrate (gypsum) scaling on selected reverse osmosis (RO) membrane surfaces was investigated experimentally in a plate-and-frame RO system. Scaling experiments with model solutions demonstrated progressive axial development of surface gypsum Crystals along the membrane surface. The impact of surface Crystallization was characterized via flux decline measurements and by both optical and high-resolution scanning electron microscopy (SEM) surface imaging. Surface coverage by gypsum scale (percent area covered and gypsum surface mass density) increased along the membranes (towards the membrane exit), consistent with the increase in concentration polarization. At the membrane channel entry, surface gypsum Crystals were at their initial growth stage formed as primarily needle-like structures. With increasing axial distance from the entry, surface Crystallization resulted in Crystal structures that transitioned from the needle and plate-like structures, in the submicron size range, to partial Rosettes to complete Rosette structures in the mm size range. Significant differences were observed in the extent of surface scale coverage and surface Crystal size among the membrane studied. Antiscalant addition to the feed solution led to progressive decline in the percent of area covered by scale with increasing antiscalant dosage and corresponding decrease in flux decline. Antiscalant addition resulted in perturbed surface Crystal morphology of flattened and/or fused Rosette Crystal arms and to complete elimination of surface Crystals at a sufficiently high antiscalant dosage. The present study demonstrates that gypsum scale development is affected by the formation of surface Crystals on the membrane surface, thereby suggesting that there is merit to expanded research on the direct impact of surface topology and chemistry on surface Crystallization of mineral salts.
Ron-wai Lee - One of the best experts on this subject based on the ideXlab platform.
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Morphometric characterization of calcium sulfate dihydrate (gypsum) scale on reverse osmosis membranes
Journal of Membrane Science, 2005Co-Authors: Wen-yi Shih, Anditya Rahardianto, Ron-wai Lee, Yoram CohenAbstract:The axial development of calcium sulfate dihydrate (gypsum) scaling on selected reverse osmosis (RO) membrane surfaces was investigated experimentally in a plate-and-frame RO system. Scaling experiments with model solutions demonstrated progressive axial development of surface gypsum Crystals along the membrane surface. The impact of surface Crystallization was characterized via flux decline measurements and by both optical and high-resolution scanning electron microscopy (SEM) surface imaging. Surface coverage by gypsum scale (percent area covered and gypsum surface mass density) increased along the membranes (towards the membrane exit), consistent with the increase in concentration polarization. At the membrane channel entry, surface gypsum Crystals were at their initial growth stage formed as primarily needle-like structures. With increasing axial distance from the entry, surface Crystallization resulted in Crystal structures that transitioned from the needle and plate-like structures, in the submicron size range, to partial Rosettes to complete Rosette structures in the mm size range. Significant differences were observed in the extent of surface scale coverage and surface Crystal size among the membrane studied. Antiscalant addition to the feed solution led to progressive decline in the percent of area covered by scale with increasing antiscalant dosage and corresponding decrease in flux decline. Antiscalant addition resulted in perturbed surface Crystal morphology of flattened and/or fused Rosette Crystal arms and to complete elimination of surface Crystals at a sufficiently high antiscalant dosage. The present study demonstrates that gypsum scale development is affected by the formation of surface Crystals on the membrane surface, thereby suggesting that there is merit to expanded research on the direct impact of surface topology and chemistry on surface Crystallization of mineral salts.
Nijsiri Ruangrungsi - One of the best experts on this subject based on the ideXlab platform.
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pharmacognostic specifications and lawsone content of lawsonia inermis leaves
Pharmacognosy Research, 2017Co-Authors: Rawiwan Charoensup, Thidarat Duangyod, Chanida Palanuvej, Nijsiri RuangrungsiAbstract:Background: Lawsonia inermis L. has been used as a traditional or folk medicine for the treatment of a wide range of skin infectious diseases. Objective: The objective of this study was to determine the pharmacognostic specifications and lawsone contents of L. inermis leaves. Materials and Methods: The pharmacognostic specifications of L. inermis leaves from 12 sources were evaluated according to the WHO guideline of quality control method for medicinal plant materials. The lawsone contents were analyzed by thin-layer chromatography (TLC) coupled with densitometry and image analysis. Results: Microscopic evaluation of L. inermis powders showed the fragment of mesophyll, fragment of parenchyma, epidermis layer with stomata, and the Rosette Crystal of calcium oxalate. Physicochemical parameters revealed that total ash, acid-insoluble ash, loss on drying, and water content should be not <6.98, 1.12, 8.08, and 9.86% of dried weight, respectively, whereas ethanol and water extractive values should be not < 19.67 and 23.06% of dried weight, respectively. The content of lawsone in L. inermis leaves by TLC-densitometry was found to be 0.76 ± 0.05 g/100 g of dried crude drug, whereas the lawsone content evaluation by TLC image analysis was found to be 0.87 ± 0.11 g/100 g of dried crude drug. The validation of the methods revealed that both TLC-densitometry and TLC image analysis showed a good sensitivity and accuracy for lawsone quantitation in L. inermis. Conclusion: The pharmacognostic specifications could be used as the standardization data of L. inermis leaves, and the development of TLC method could be applied to determine lawsone content in this plant material.
