A novel bioreactor containing self-flocculated anaerobic granular sludge was developed for high-performance hydrogen production from sucrose-based synthetic wastewater. The reactor achieved an optimal volumetric hydrogen production rate of ~7.3 L/h/L (7.150 mmol/d/L) and a maximal hydrogen yield of 3.03 mol H2/mol sucrose when it was operated at a hydraulic retention time (HRT) of 0.5 h with an influent sucrose concentration of 20 g COD/L. The gasphase hydrogen content and substrate conversion also exceeded 40 and 90%, respectively, under optimal conditions. Packing of a small quantity of carrier matrices on the bottom of the upflow reactor significantly stimulated sludge granulation that can be accomplished within 100 h. Among the four carriers examined, spherical activated carbon was the most effective inducer for granular sludge formation. The carrierinduced granular sludge bed (CIGSB) bioreactor was started up with a low HRT of 4-8 h (corresponding to an organic loading rate of 2.5-5 g COD/h/L) and enabled stable operations at an extremely low HRT (up to 0.5 h) without washout of biomass. The granular sludge was rapidly formed in CIGSB supported with activated carbon and reached a maximal concentration of 26 g/L at HRT = 0.5 h. The ability to maintain high biomass concentration at low HRT (i.e., high organic loading rate) highlights the key factor for the remarkable hydrogen production efficiency of the CIGSB processes.

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Packed-bed bioreactors containing activated carbon as support carrier were used to produce H2 anaerobically from a sucrose-limiting medium while acclimated sewage sludge was used as the H2 producer. The effects of bed porosity (epsilon(b)) and substrate loading rate on H2 fermentation were examined using packed beds with epsilon(b) of 70-90% being operated at hydraulic retention times (HRT) of 0.5-4 h. Higher epsilon(b) and lower HRT favored H2 production. With 20 g COD l(-1) of sucrose in the feed, the optimal H2 production rate (7.4 l h(-1) l(-1)) was obtained when the bed with epsilon(b) = 90% was operated at HRT = 0.5 h. Flocculation of cells enhanced the retention of sludge for stable operations of the bioreactor at low HRTs. The gas products resulting from fermentative H2 production consisted of 30-40% H2 and 60-70% CO2. Butyric acid was the primary soluble product, followed by propionic acid and valeric acid.

Producing a lifelike 3D facial expression is usually a labor-intensive process. In movie and game industries, motion capture and 3D scanning techniques, acquiring motion data from real persons, are used to speed up the production. However, acquiring dynamic and subtle details, such as wrinkles, on a face are still difficult or expensive. In this paper, we propose a feature-point-driven approach to synthesize novel expressions with details. Our work can be divided into two main parts: acquisition of 3D facial details and expression synthesis. 3D facial details are estimated from sample images by a shape-from-shading technique. While employing relation between specific feature points and facial surfaces in prototype images, our system provides an intuitive editing tool to synthesize 3D geometry and corresponding 2D textures or 3D detailed normals of novel expressions. Besides expression editing, the proposed method can also be extended to enhance existing motion capture data with facial details.