Urinary type calcium hydrogen phosphate dihydrate (CHPD) or Brushite crystals were grown by the single diffusion gel technique in silica hydro-gels. The gel framework acts as a three dimensional crucible in which the crystal nuclei are delicately held in the position of their formation and nutrients are supplied for their growth. This technique can be utilized as a simplified screening model to study the growth and dissolution of urinary stones in vitro. The action of the putatively litholytic medicinal plants Tribulus terrestris and Bergenia ligulata on the growth of CHPD crystals was studied . The effects of artificial reference urine (ARU) and human urine (HU), along with the plant extracts, are also reported. Attempts were made to understand the role of these inhibitors on urinary crystal formation. HU, ARU, extracts of B. ligulata and T. terrestris exhibit appreciable amounts of inhibition, but B.ligulata and T.terrestris with ARU and HU do not show inhibition at all.

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Potassium dihydrogen phosphate (KDP) is a well known nonlinear optical (NLO) material with different applications. Since most of the amino acids exhibit NLO property, it is of interest to dope them in KDP. In the present study, amino acid L-arginine was doped in KDP. The doping of L-arginine was confirmed by FT-IR and paper chromatography. Thermogravimetry suggested that as the amount of doping increases the thermal stability decreases as well as the value of thermodynamic and kinetic parameters decreases. The second harmonic generation (SHG) efficiency of L-arginine doped KDP crystals was found to be increasing with doping concentration of L-arginine. The results are discussed here.

Potassium Dihydrogen Phosphate (KDP) is an excellent inorganic nonlinear optical (NLO) material with different device applications. Most of amino acids possess NLO property; therefore, it is of interest to dope them in KDP crystals. In the present study, amino acid L-alanine doped KDP crystals were grown by slow aqueous solvent evaporation technique. The doping of L-alanine was confirmed by the paper chromatography, the CHN analysis and the FT-IR spectroscopy. The powder XRD was carried out to assess the single phase nature of the samples. The effect of doping on thermal stability of the crystals was studied by TGA and the kinetic and thermodynamic parameters of dehydration were evaluated. As the amount of doping increased the thermal stability of crystals decreased. However, the second harmonic generation (SHG) efficiency and the UV-Vis spectroscopy studies indicated that as the L-alanine doping increased the SHG efficiency and optical transmission percentage increased. The dielectric behavior of the samples has been studied. The variation of dielectric constant, dielectric loss (tanδ), a.c.resistivity and a.c.conductivity with frequency of applied field in the range from 100 Hz to 100 kHz was studied. The dielectric constant and dielectric loss decreased with increase the value of frequency of applied field. The dielectric constant and the dielectric loss values of L-alanine doped KDP crystals were lower than the pure KDP crystals. The results are discussed.