Phase separated metallic glasses were prepared in the ternary Ni-Nb-Y system by rapid quenching of the melt. For Ni-rich alloys, early stage of spinodal decomposition or an almost homogeneous glassy state is obtained due to the reduction of the critical temperature of liquid-liquid phase separation near to the glass transition temperature. In situ small-angle X-ray scattering at elevated temperature gives evidence of on-going phase separation of the glass prior to crystallisation. The structural changes during isothermal heat treatment point to a spinodal mechanism of the decomposition. For glass with low Y-content (5 at %) no indication of phase separation is found in accordance with the composition dependence of the metastable miscibility gap of the supercooled liquid. Upon heating, the phase separated glass becomes a precursor and causes the nanostructure of the Ni2Y-phase formed as the first stage of crystallization. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64

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A simple and rapid TLC method using densitometric detection was developed for the simultaneous analysis of four SSRI antidepressants: citalopram, sertraline, fluoxetine, and fluvoxamine. The analytes were separated on silica gel 60 F 254s TLC plates using a mobile phase composed of acetonebenzene-ammonia (50:45:5, v/v/v). Densitometric detection and quantification were carried out in the reflectance mode at 240 nm. The calibration curve was linear in the range of 500-5000 ng per spot for all analyzed compounds. The limit of detection was 40 ng per spot for citalopram and 50 ng per spot for fluoxetine, fluvoxamine, and sertraline, respectively. Statistical analysis proves that the method is both precise and accurate. The proposed method was successfully applied for the determination of citalopram and fluoxetine in their pharmaceutical formulations, with recoveries ranging from 98.7-101.9% of the labeled amount of the compounds. Finally, the reported method was also applied to the analysis of antidepressants in real biological samples.

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