An efficient synthesis of 2,4,5-trisubstituted and 1,2,4,5-tetrasubstituted imidazoles by one-step condensation of  an aldehyde, benzil, ammonium acetate and primary amine in the presence of nanocrystalline magnesium aluminate under microwave irradiation is described. The advantages of this catalyst are including simple work-up, low cost and reusability. Compared with conventional methods, the ...

ZnO microand nanostructures have been produced using a large number of different synthetic routes, and the applications that utilize their unique properties keep increasing. The 3.3 eV direct bandgap and 60 meV exciton binding energy is exploited in ultraviolet optoelectronics, room-temperature lasing, and solar cells applications; extremely long photocarrier lifetimes have been observed yieldi...

Government regulations to address technological risks are important for the successful development and application of nanotechnology, but there is an ongoing debate in the USA about who is responsible for the regulation of nanotechnology. In a mail survey of leading US nano-scientists, we examine scientists’ perceptions about nano-regulation, including the government level (local, national, or ...

Single crystals of stoichiometric MgA1204 spine1 were neutron-irradiated to fluences (> 0.1 MeV) of 2.8 x loz5 n m-2 (1.5 dpa) at 1015 K and 1.9 x loz6 n m-2 (10 dpa) at 925 K and 1 100 K. The resulting point defect'aggregates were investigated using bright-field and weak-beam dark-field transmission electron microscopy. For the higher dose, faulted interstitial Frank dislocation loops were fou...