We investigated the performance of a 15.3 L capacity anaerobic baffled reactor （ABR） toward the treatment of low-strength domestic wastewater. The start- up period of the ABR was finished within approximately 130 da...We investigated the performance of a 15.3 L capacity anaerobic baffled reactor （ABR） toward the treatment of low-strength domestic wastewater. The start- up period of the ABR was finished within approximately 130 days at a temperature below 25~C. The average CODcr in the effluent was 165 mg.L 1 and the corresponding CODcr removal efficiency of the ABR was 52.3%. During the third stage （from day 130 to day 233） of ABR operation, the average CODcr in the effluent reached 71 mg· L^-1, which meets the secondary discharge requirement of the Integrated Wastewater Discharge Standard （GB 18918-2002, China）. Moreover, partial microbial separa- tion was observed along the five ABR compartments through scanning electron microscopic images. The geometric mean diameter of bioparticles in the five compartments increased from 0.050 mm to 0.111, 0.107, 0.104, 0.110, and 0.103 mm during the start-up stage. After operation for 179days, the further increased to 0.376, corresponding diameters 0.225, 0.253, 0.239, and 0.288mm, respectively. The fractal dimensions of the bioparticles indicated that these particles have smoother surfaces and more compact structures during ABR operation. Morphological analysis of the bioparticle sections demonstrated that the bioparticles have a pore volume of 30%-55%. The highest porosity was observed for the bioparticles in the second ABR compartment, whereas the lowest fractal dimension ofbioparticle section was observed in the fifth compartment.展开更多
We demonstrate the layer-by-layer(LbL)assembly of polyelectrolyte multilayers(PEM)on three-dimensional nanofiber scaffolds.High porosity(99%)aligned carbon nanotube(CNT)arrays are photolithographically patterned into ...We demonstrate the layer-by-layer(LbL)assembly of polyelectrolyte multilayers(PEM)on three-dimensional nanofiber scaffolds.High porosity(99%)aligned carbon nanotube(CNT)arrays are photolithographically patterned into elements that act as textured scaffolds for the creation of functionally coated(nano)porous materials.Nanometer-scale bilayers of poly(allylamine hydrochloride)/poly(styrene sulfonate)(PAH/SPS)are formed conformally on the individual nanotubes by repeated deposition from aqueous solution in microfluidic channels.Computational and experimental results show that the LbL deposition is dominated by the diffusive transport of the polymeric constituents,and we use this understanding to demonstrate spatial tailoring on the patterned nanoporous elements.A proof-of-principle application,microfluidic bioparticle capture using N-hydroxysuccinimide-biotin binding for the isolation of prostate-specific antigen(PSA),is demonstrated.展开更多
基金Acknowledgements This work was supported by the Fundamental Research Funds for the Central Universities （Nos. JC2011-1 and TD2010- 5）, Major projects on control and rectification of water body pollution （No. 2008ZX07314-006-02）, the National Natural Science Foundation of China （Grant Nos. 51078035 and 21177010）, and the Ph.D. Programs Foundation of the Ministry of Education of China （No. 20100014110004）.
文摘We investigated the performance of a 15.3 L capacity anaerobic baffled reactor （ABR） toward the treatment of low-strength domestic wastewater. The start- up period of the ABR was finished within approximately 130 days at a temperature below 25~C. The average CODcr in the effluent was 165 mg.L 1 and the corresponding CODcr removal efficiency of the ABR was 52.3%. During the third stage （from day 130 to day 233） of ABR operation, the average CODcr in the effluent reached 71 mg· L^-1, which meets the secondary discharge requirement of the Integrated Wastewater Discharge Standard （GB 18918-2002, China）. Moreover, partial microbial separa- tion was observed along the five ABR compartments through scanning electron microscopic images. The geometric mean diameter of bioparticles in the five compartments increased from 0.050 mm to 0.111, 0.107, 0.104, 0.110, and 0.103 mm during the start-up stage. After operation for 179days, the further increased to 0.376, corresponding diameters 0.225, 0.253, 0.239, and 0.288mm, respectively. The fractal dimensions of the bioparticles indicated that these particles have smoother surfaces and more compact structures during ABR operation. Morphological analysis of the bioparticle sections demonstrated that the bioparticles have a pore volume of 30%-55%. The highest porosity was observed for the bioparticles in the second ABR compartment, whereas the lowest fractal dimension ofbioparticle section was observed in the fifth compartment.
基金This work was supported by the MRSEC Program of the National Science Foundation under award number DMR-0819762.
文摘We demonstrate the layer-by-layer(LbL)assembly of polyelectrolyte multilayers(PEM)on three-dimensional nanofiber scaffolds.High porosity(99%)aligned carbon nanotube(CNT)arrays are photolithographically patterned into elements that act as textured scaffolds for the creation of functionally coated(nano)porous materials.Nanometer-scale bilayers of poly(allylamine hydrochloride)/poly(styrene sulfonate)(PAH/SPS)are formed conformally on the individual nanotubes by repeated deposition from aqueous solution in microfluidic channels.Computational and experimental results show that the LbL deposition is dominated by the diffusive transport of the polymeric constituents,and we use this understanding to demonstrate spatial tailoring on the patterned nanoporous elements.A proof-of-principle application,microfluidic bioparticle capture using N-hydroxysuccinimide-biotin binding for the isolation of prostate-specific antigen(PSA),is demonstrated.
