1,650 research outputs found

    Viscosity scaling of fingering instability in finite slices with Korteweg stress

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    We perform linear stability analyses (LSA) and direct numerical simulations (DNS) to investigate the influence of the dynamic viscosity on viscous fingering (VF) instability in miscible slices. Selecting the characteristic scales appropriately the importance of the magnitude of the dynamic viscosity of individual fluids on VF in miscible slice has been shown in the context of the transient interfacial tension. Further, we have confirmed this result for immiscible fluids and manifest the similarities between VF in immiscible and miscible slices with transient interfacial tension. In a more general setting, the findings of this letter will be very useful for multiphase viscous flow, in which the momentum balance equation contains an additional stress term free from the dynamic viscosity.Comment: 16 pages, 8 figure

    Structure and optical properties of Cd substituted ZnO (Zn1-xCdxO) nanostructures synthesized by high pressure solution route

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    We report synthesis of Cd substituted ZnO nanostructures (Zn1-xCdxO with x upto \approx .09) by high pressure solution growth method. The synthesized nanostructures comprise of nanocrystals that are both particles (~ 10-15 nm) and rods which grow along (002) direction as established by Transmission electron microscope (TEM) and X-ray diffraction (XRD) analysis. Rietveld analysis of the XRD data shows monotonous increase of the unit cell volume with the increase of Cd concentration. The optical absorption as well as the photoluminescence (PL) shows red shift on Cd substitution. The line width of the PL spectrum is related to the strain inhomogenity and it peaks in the region where the CdO phase separates from the Zn1-xCdxO nanostructures. The time resolved photoemission showed a long lived (~10ns) component. We propose that the PL behavior of the Zn1-xCdxO is dominated by strain in the sample with the redshift of the PL linked to the expansion of the unit cell volume on Cd substitution

    Finite Size Effect from Classical Strings in deformed AdS3×_3\times S3^3

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    We study the finite size effect of rigidly rotating and spinning folded strings in (AdS3×S3)ϰ(AdS_3\times S^3)_{\varkappa} background. We calculate the leading order exponential corrections to the infinite size dispersion relation of the giant magnon, and single spike solutions. For the spinning folded strings we write the finite size effect in terms of the known Lambert WW-function.Comment: to appear in JHE
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