Spectroscopic study on the interactions of trace elements Co., Mn, Mg and Al with d(GCGTACGC) indicated the following: Al and Mg did not alter Tm values. Mn enhanced Tm at lower concentration and decreased it at higher concentrations. Interestingly Co at higher concentration elevated the Tm. These studies also showed lower concentrations of Mn displaced EtBr, whereas Al could displace it at higher ionic strength. Mg and Co displaced EtBr fluorescence at moderate concentrations. The binding constant values and CD spectra clearly indicated strong binding of these elements to DNA.

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Heat transfer rates measured in front and to the side of a protrusion on an aluminum flat plate subjected to hypersonic flow at zero angle of attack are presented for two flow enthalpies of approximately 2 M J/kg and 4.5 M J/kg. Experiments were conducted in the hypersonic shock tunnel (HST2) and free piston driven HST3 at a freestream Mach number of 8. Heat transfer data was obtained for different geometries of the protrusion of a height of 4 mm, which is approximately the local boundary layer thickness. Comparatively high rates of heat transfer were obtained at regions of flow circulation in the separated region, with the hottest spot generally appearing in front of the protuberance. Experimental values showed moderate agreement with existing empirical correlations at higher enthalpy but not at all for the lower enthalpy condition, although the correlations were coined at enthalpy values nearer to the lower value. Schlieren visualization was also done to investigate the flow structures qualitatively.

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