Dipole moments and molecular conformations of some thioanhydrides

Electric dipole moments of methyl thiobenzoate (1.70 D), thiophthalic anhydride (3.92 D) and dibenzoyl sulphide (3.88 D) have been measured in benzene at 25° C. The predicted moments of these compounds were calculated and the results interpreted in terms of their conformations.     

The Iwasawa Main Conjectures for GL2

We prove the one-, two-, and three-variable Iwasawa-Greenberg Main Conjectures for a large class of modular forms that are ordinary with respect to an odd prime p. The method of proof involves an analysis of an Eisenstein ideal for ordinary Hida families for GU(2,2).     

Gamma induced changes in Makrofol/CdSe nanocomposite films

We applied an ex-situ casting procedure to prepare a nanocomposite (NCP) from Makrofol polycarbonate (PC) and CdSe nanoparticles. The CdSe nanoparticles were prepared by a thermolysis procedure in the presence of N₂ gas flow. Rietveld refinement of x-ray data illustrated that the CdSe adopts a cubic zinc blend structure of 6.057 Å lattice parameter and 2 nm typical grain size. Samples from the prepared NCP were exposed to γ dosages (20 kGy-250 kGy). The modifications induced in the NCP films owing to γ dosages have been studied. The γ irradiation (50 kGy-250 kGy) causes crosslinks that reduce the optical bandgap from 4.15 eV to 3.81 eV, associated with an increase in dielectric parameters and refractive index. This is attributed to an increase in the mass fraction of the disordered regions as specified by x-ray diffraction. The PC-CdSe NCP was found to have a reaction to color modification which makes it suitable for saleable reproduction on a printing press.