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An efficient nonlinear optical single crystal of 2-phenylethylammonium p-hydroxybenzoate (2PPHB) was grown from aqueous solution by slow evaporation solution growth method. Single crystal X-ray diffraction studies confirmed that 2PPHB crystallizes in orthorhombic crystal system with non-centrosymmetric space group of Pna21. The presence of functional groups in the synthesized compound was identified by FTIR spectral analysis. The grown crystals were thermally stable up to 155°C. UV-vis absorption, photoluminescence and birefringence optical properties of grown crystal were explored. The laser induced surface damage threshold and relative second harmonic generation properties of the grown crystal were studied using Q-switched Nd:YAG laser. The variation of dielectric properties of the grown crystal with frequency was investigated for different temperatures. The mechanical response of the crystal was studied by Vicker's microhardness technique. [ABSTRACT FROM AUTHOR]

Abstract: Palladium nanocatalysts supported on surface-oxidized multiwalled carbon nanotubes (MWNT) were prepared by the aqueous solution reduction of . MWNT have been synthesized by catalytic chemical vapor deposition (CCVD) technique. Pyrolysis of acetylene using a fixed-bed catalytic reactor over rare earth (RE) based alloy hydride catalyst, obtained through hydrogen decrepitation technique, has been performed to synthesize MWNT. Structural, morphological and vibrational characterizations have been carried out using XRD, SEM, TEM and Raman spectroscopy, respectively. In situ electrical resistance measurements for thin films of MWNT obtained by spin coating samples were carried out by two-probe technique in a chamber with provision to introduce known concentration of hydrogen in constant air flow. Investigations of hydrogen sensing properties of Pd–MWNT ensembles have been carried out. The stability of Pd–MWNT thin films after several cycles of adsorption and desorption was studied. The change in electrical resistance due to hydrogen adsorption is reversible, with increase to saturation on exposure to hydrogen gas. The results demonstrate that chemically treated MWNT functionalized with nanostructured Pd show good sensing response at room temperature. [Copyright &y& Elsevier]

Abstract: Hydrogen absorption pressure-composition (–) isotherms of C15 Laves phase (, 0.05, 0.1, 0.15, 0.2) alloys have been investigated by pressure reduction method using Sieverts’ apparatus, in the ranges and , respectively. The – isotherms show the presence of a single plateau region in the temperature and pressure ranges studied. The dependences of the plateau pressure at any given temperature and the hydrogen storage capacity at any particular pressure and temperature on the Mischmetal (Mm) content have been discussed. The dependence of the thermodynamics of dissolved hydrogen in these alloy hydrides on the hydrogen concentration has been studied. The absorption of hydrogen is accompanied by a maximum of 16–18% unit cell volume expansion in the host material without any structural changes as evidenced by the powder X-ray diffraction studies of alloy hydrides. Instead, hydrogen induced amorphization (HIA) at higher hydrogen concentration has been observed. The dependence of HIA on Mm content has been discussed. In addition, the kinetics of hydrogen absorption have been studied in the temperature range and activation energy for the and phase and the diffusion coefficient in the phase have been calculated from the hydrogen absorption kinetics and the results have been discussed. [Copyright &y& Elsevier]

• Ag 2 O NPs were synthesized by greener method using Zephyrathes Rosea flower extract. • Optical absorption peak of Ag 2 O NPs was observed at 420 nm and the band gap energy was 2.48 eV. • Ag 2 O NPs has spherical morphology with particle size in the range of 10−30 nm. • It is found that, Ag 2 O NPs exhibits very good anti-bacterial, anti-inflammatory activities. Bio-nanotechnology is an effective technique for the synthesis of nanoparticles in a greener approach without affecting the environment. The present research provides the in-vitro synthesis of Zephyranthes Rosea flower extract substituted silver oxide nanoparticles by a greener approach for the first time. The formation of the face centered cubic structure of Ag 2 O NPs was confirmed by X-ray diffraction (XRD) pattern. The synthesized nanoparticles were characterized by X-ray Photoelectron Spectroscopy (XPS) analysis to confirm the chemical states and purity of Ag and O. The optical absorption peak of the nanoparticle was found to be at 420 nm and optical emission peaks were observed at 412 nm, 485 nm, and 530 nm. The bandgap energy of the Ag 2 O NPs was found to be 2.48 eV. The morphology of the nanoparticles was found to be spherical with the particle size about 10−30 nm and the lattice inter-planar spacing was found to be 0.222 nm. Ag 2 O NPs Zephyranthes Rosea were found to be a potential candidate for the antibacterial activity against the strains of E scherichia coli , Streptococcus mutants, and Staphylococcus aureus. The antioxidant activity of Ag 2 O NPs was found to be 73.82 % at 100 μg/mL with the standard drug of ascorbic acid. The anti-inflammatory activity of the Ag 2 O NPs was found to be 97.19 % at 500 μg/mL using the BSA denaturation technique. The anti-diabetic activity of the Ag 2 O NPs was tested by α-amylase assay and the inhibition percentage was found to be 75.7 % at 500 μg/mL. [ABSTRACT FROM AUTHOR]