02317nas a2200217   4500008004100000022001400041245011300055210006900168260006900237300001200306490000800318520148300326653002101809653002901830653001701859653002401876100002301900700003001923700002301953856012301976       2012                        eng d  a1385-894700aSegmented flow synthesis of Ag nanoparticles in spiral microreactor: role of continuous and disperzsed phase0 aSegmented flow synthesis of Ag nanoparticles in spiral microreac  aPO BOX 564, 1001 LAUSANNE, SWITZERLANDbELSEVIER SCIENCE SAcJUN  a357-3680 v1923 a<p>This work focuses on understanding the effect of segmented flow on the nanoparticle size distribution in a unidirectionally expanding spiral microreactor, where secondary flows are prevalent in the absence of segmentation. Stearic acid sophorolipid reduced/capped Ag NPs were synthesized in the aqueous phase and air or kerosene was used as inert phases for creating the gas-liquid and liquid-liquid segmented flow, respectively. While, in one case the reactant phase is in the form of dispersed phase slugs, in the other case it is in the form of continuous phase, each exhibiting a different behavior. The slug sizes and the slip velocity, both of which govern the nature of internal mixing in the reactant phase slug controlled the nanoparticle size distribution. This observation was consistent for both, gas-liquid and liquid-liquid segmented flows. The micromixer having smaller orifice diameter yielded smaller slugs and also a narrow particle size distribution. In general, the particle sizes were much smaller for gas-liquid flow rather than for liquid-liquid flow. Because of the unidirectionally expanding spiral geometry of the channel, at any given condition, unsteady behavior of slugs due to continuously varying radius of curvature results in variation in the slip velocity along the length of microchannel. This effect was seen to further narrow the particle size distribution than alone by the segmented flow. (C) 2012 Elsevier B.V. All rights reserved.</p>10aAg nanoparticles10aSegmented flow synthesis10aSophorolipid10aSpiral microreactor1 aKumar, D., V. Ravi1 aPrasad, Bhagavatula L. V.1 aKulkarni, Amol, A.  uhttps://library.ncl.res.in/content/segmented-flow-synthesis-ag-nanoparticles-spiral-microreactor-role-continuous-and-0