Exhaust emissions contribute greatly to air pollution, the social cost of which may occur as danger to human health, attracting huge medical expenses, causing absenteeism and hence loss of productivity. These are incentives to reduce exhaust emissions to the barest minimum. Two major cities in Ghana, Accra and Kumasi, are struck by vehicular traffic jams especially during rush-hours and are gra...

Robust luminophores emitting light with broadly tunable colors are desirable in many applications such as light-emitting diode (LED)-based lighting, displays, integrated optoelectronics and biology. Nanocrystalline quantum dots with multicolor emission, from core- and shell-localized excitons, as well as solid layers of mixed quantum dots that emit different colors have been proposed. Here, we ...

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In some luminous organisms (firefly, Cypridina, and bacteria) it is possible to obtain cell-free luminescence by the combination of a cold water extract (luciferase) with a hot water extract (luciferin). Failure in the past to observe such a reaction with extracts of luminous fungi can now be shown to be due to the following factors: (a) in crude aqueous extracts the luciferase is either too di...

The use of optics in microelectronic circuits to overcome the limitation of metallic interconnects is more and more considered as a viable solution. Among future silicon compatible materials, carbon nanotubes are promising candidates thanks to their ability to emit, modulate, and detect light in the wavelength range of silicon transparency. We report the first integration of carbon nanotubes wi...