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Low-temperature combustion in biomass-burning stoves used for cooking results in poor thermal efficiency and high emissions. A sawdust packed-bed stove has been shown to give more stable combustion at higher temperatures than woodstoves. The study examines pollutant emissions from this stove and their dependence on stove dimensions, specifically the vertical port radius and the stovepot spacing. Emission rates of particulate matter (PM)-along with size resolution-and of carbon monoxide (CO) were measured during steady-state combustion. The stove power increased with increased spacing and vertical port radius. However, the air-flow rate, combustion temperature, and air-fuel ratio showed complex variations with stove dimensions from the described coupling among the pyrolysis, combustion, induced air flow, and mixing. Emission rates of PM (0.21-0.36 gh −1 ) and CO (3-8 gh −1 ) and were a factor of ten lower than those previously measured from woodstoves. Emission rates of CO decreased, while PM increased, with increasing combustion temperature. Aerosol size distributions were unimodal with mass median aerodynamic diameters (MMAD) of 0.24-0.40 µm, a factor of two smaller than from woodstoves. Cool combustion at 534-625• C gave lower PM emission rates but particles of larger MMAD, while hot combustion at 625-741• C gave higher PM emission rates with smaller particle MMAD. The OC/EC ratio obtained for cool combustion was higher (1.20) than that for hot combustion (0.96). Greater elemental carbon formation was seen at the higher temperatures. PM and CO emission rates followed opposite trends with combustion temperature and stove configuration, resulting in no single configuration at which both CO and PM emissions were minimized. However, its superior thermal efficiency and signifi-

A contact lens embeddable display using electro-optic modulation was designed and fabricated. Using a guest–host liquid crystal configuration, a spherically deformed liquid crystal cell was fabricated comprising poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT : PSS) as a conductive layer and obliquely evaporated SiO2 as an alignment layer. An additional SiO2 buffer layer was evaporated on top of the PEDOT : PSS to overcome compatibility problems with the patterning of the photolithographically defined spacers. Although the contrast is modest, a patterned modulation could clearly be observed, indicating that our approach and fabrication process could eventually lead to a fully pixelated contact lens display