We have studied the Cr-K-edge XANES and EXAFS in natural Indian rubies from two sources and a synthetic ruby at ESRF. Weight % of various constituents in them is determined using EDAX measurements. Taking the results from the three techniques together we are able to demonstrate their feasibility in quantitative study of precious stones.

Total Yield with an escape depth of ~100-200 Å is known to be rather surface sensitive. Fluorescence Yield, on the other hand, with an escape depth of ~1000-2000 Å is relatively less prone to surface effects but necessitates some corrections to obtain the true signal. Both have their plus and minus points and, if used with care, yield reliable data. In the present experiment both the techniques have been simultaneously employed for measuring orientation dependent O K and the Cu L 3 edges from an uncleaved surface of I(2)BSCCO(2212) single crystal to compare the performance of the two modes of detection. Despite glaring differences in intensities the results from the two appear to show reasonable agreement in respect of relative intensities of the spectral features.

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In India, more than 38,000 blood donations are needed every day, and a total of 30 million blood components are transfused each year. Blood type matching is crucial for blood transfusion and blood donation. The conventional method uses blood slides, pricking needles, and blood typing kit, and takes about 15 minutes for deciding the blood group. However, in case of emergency, it is time-consuming to determine blood type using the conventional method of reagents. At blood donation camps, it is a tedious job to determine the blood group of every donor using the blood typing kit. Pricking needles and slides used can also cause infection to the person performing these tests. The main motive is to replace this tedious and time-consuming method with a non-invasive accurate and reagent free method, using an optimum wavelength light source, photo-detectors, and controller unit for decision making of blood type from output mapping or intensity matching of the scattered and transmitted wavelength from the source to detector.

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