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High-resolution transmission electron microscopy and Auger spectroscopy have revealed the formation of nanometer-thick, Ni-enriched, disordered, grain boundary layers in Ni-doped W specimens at 95°C below the bulk eutectic temperature. The stabilization of subeutectic liquid-like grain boundary cores in this model two-component metallic alloy is phenomenologically analogous to the long-sought phenomenon of grain boundary premelting. The existence of such disordered nanostructures at metallic grain boundaries provides insights to resolve several long-standing controversies in interpreting the unique grain boundary diffusion/migration kinetics and mechanical properties for this system, and can have technological importance for a broader range of materials.

A number of new 4-aryloxymethylcoumarins 3 and 5 have been obtained from the reaction of various 4-bromomethylcoumarins with 2-nitro-p-cresol 2 and 2,6-dibromo-p-cresol 4. NOE studies have been carried out on two compounds to ascertain their spatial proximity. p-cresol ethers 7 have been subjected to bromination in chloroform and the position of bromine has been established by diffraction studies. Cleavage of the ether linkage has been observed during an attempted nitration of ethers 7. Antimicrobial activity of all the compounds against five bacterial and five fungal species have been reported.

A metal-free cross-dehydrogenative coupling method for the synthesis of N-substituted azoles has been developed. The TBAI/TBHP system catalyzed the coupling of azoles with ethers and thioethers via α-C(sp(3))-H activation. Under the optimized conditions, a diverse range of un/substituted azoles such as 1H-benzimidazole, 9H-purine, 1H-benzotriazole, 1H-1,2,3-triazole, 1H-1,2,4-triazole, and 1H-pyrazole were successfully employed for coupling with various ethers and thioethers such as tetrahydrofuran, tetrahydropyran, 1,4-dioxane, diethyl ether, tetrahydrothiophene, and 1,3-dithiolane.

1-Phenyl-3-methyl-4-touloyl-5-pyrazolone (ligand) was synthesized and used to prepare an oxovanadium(IV) complex. The complex was characterized by single-crystal X-ray analysis and various spectroscopic techniques. The single-crystal X-ray analysis of the complex shows that the ligands are coordinated in a syn configuration to each other and create a distorted octahedral environment around the metal ion. A heterogeneous catalyst comprising an oxovanadium(IV) complex and hydrous zirconia was synthesized, characterized by various physicochemical techniques, and successfully used for the solvent-free oxidation of styrene. The influence of the reaction parameters (percent loading, molar ratio of the substrate to H(2)O(2), amount of catalyst, and reaction time) was studied. The catalyst was reused three times without any significant loss in the catalytic activity.

Several 3-[5-(4-substituted)phenyl-1,3,4-oxadiazole-2-yl]-2-styryl quinazoline-4(3H)-one were synthesized and screened for antibacterial activity against Staphylococcus aureus , Bacillus subtilis, Pseudomonas aeruginosa, and Escherichia coli and antifungal activity against Aspergillus niger and Fusariumoxysporum by the serial dilution technique. Compounds were prepared by reacting corresponding 2-methtyl quinazolinone and 4-subustituted benzaldehydes in glacial acetic acid. Physicochemical and spectral data were consistent with newly synthesized compounds. The prepared compounds were compared with previously synthesized 2-methyl-3-[5-(4-substituted)phenyl-1,3,4-oxadiazole-2-yl]-quinazoline-4(3H)-ones for antimicrobial activity. The present study revealed that styryl moiety at the second position of 4(3H) quinazolinone marginally increased the biological activity and exhibited better antibacterial than antifungal activities.

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