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Epoxy resins have been extensively utilized for mechanical strength applications in the field of aerospace, automobiles, marine, defence, etc. Improving the strength as well as fracture behaviour of the light weight materials is challenging. Present work is an attempt to enhance elastic modulus, hardness and fracture resistance simultaneously by reinforcing the epoxy (bisphenol-A) matrix with a new-age two-dimensional atomically thin graphene oxide filler. Wet chemical oxidation method was used to prepare graphene oxide sheets. Morphological study of the synthesized graphene oxide was carried out using scanning electron microscopy. Fourier-transformed infrared, ultraviolet–visible and Raman spectroscopic techniques were also employed to ascertain the synthesis of graphene oxide. The results confirmed the synthesis of well oxidized graphene oxide sheets. The prepared graphene oxide sheets were then sonicated in acetone solution to ensure better dispersion in the bisphenol-A graphene oxide nano-composite using 0.25, 0.5, 1.0 and 1.5 wt.% graphene oxide reinforcement. Solution mixing method was used to synthesize the polymer nano-composite. Scanning electron microscopy results revealed the smooth dispersion of graphene oxide in the bisphenol-A matrix. Nano-indentation of the bisphenol-A graphene oxide nano-composite showed a considerable jump in elastic modulus at 1 wt.% and hardness at 0.50 wt.% of graphene oxide reinforcement. Fracture resistance of bisphenol-A graphene oxide composite as represented by ratio of elastic modulus to hardness was enhanced by 24% as compared to the pristine bisphenol-A. Our results demonstrate a promising way to improve the mechanical characteristics of epoxy resins through graphene oxide reinforcement at low weight percentages.

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Two new collective bands have been identified in 12~ nucleus from the cross-bombardment results of wsPd (~60,p3n) and ll4Cd (IB,5n) nuclei. Such staggered and non-staggered collective bands have been established in the well-deformed odd-odd Cs [5] and La [6] nuclei. To further explore such staggered bands in nuclei in the vicinity of Z=50 closure, the high spin structures in odd-odd '2~ nucleus have been investigated.Excited states in 12~ were populated through the ~~ and n4Cd(nB,5n) reactions at 84 and 60 MeV respectively. The ion beams were delivered by the 16UD pelletron accelerator at Nuclear Science Centre, New Delhi. Isotopically enriched foils of ~~ (lmg/cm 2) and 114Cd (3mg/cm=) rolled on thick Pb backing were used as targets. Coincident ),-rays were detected with the GDA set-up comprising of eight Compton suppressed Ge detectors along with the multiplicity ball of fourteen BGO crystals. A total of 75 and 100 million Ge-Ge-BGO coincidences were recorded in these experiments respectively.The level scheme inferred from the present work is shown in figure 1. The placement of y-transitions is 2 (2t -) 12~l (16-)