Wood biomass is anticipated to serve as a substitute for carbon source, which has no feedstock competition with foods. Biomass is commonly used for the production of bio-ethanol by a series of processes such as pretre...Wood biomass is anticipated to serve as a substitute for carbon source, which has no feedstock competition with foods. Biomass is commonly used for the production of bio-ethanol by a series of processes such as pretreatment, enzymatic degradation, and fermentation. Hemicellulose, constituting 20 wt-% - 40 wt-% ofbiomass materials, contains various kinds of saccharides known to be bioactive substrates. Practical usage of hemicellulose is generally limited to its conversion to bio-ethanol. Here, we aimed to prepare hemicellulolic oligosaccharides, more valuable products other than ethanol. Therefore, the Hinoki slurry was treated with lime at room temperature for 3 h, and then neutralized with HCI. The resulting sample was treated with 13 types of commercial enzymes, and the saccharides produced in the supernatant were evaluated. The result showed that the commercial enzyme Cellulase SS （Nagase ＆ Co., LTD.） effectively degraded the slurry to produce disaccharides and trisaccharides. Analysis of sugar components by liquid chromatography/mass spectrography （LC/MS） after the derivation with ethyl 4- aminobenzoate （ABEE） showed that mannobiose, manno- Nose, and cellobiose were the major oligosaccharides. These results indicate valuable oligosaccharides can be successfully produced from Hinoki softwood slurry.展开更多
The authors establish error estimates for recently developed finite-element methods for incompressible viscous flow in domains with no-slip boundary conditions.The methods arise by discretization of a well-posed exten...The authors establish error estimates for recently developed finite-element methods for incompressible viscous flow in domains with no-slip boundary conditions.The methods arise by discretization of a well-posed extended Navier-Stokes dynamics for which pressure is determined from current velocity and force fields.The methods use C1 elements for velocity and C0 elements for pressure.A stability estimate is proved for a related finite-element projection method close to classical time-splitting methods of Orszag,Israeli,DeVille and Karniadakis.展开更多
文摘Wood biomass is anticipated to serve as a substitute for carbon source, which has no feedstock competition with foods. Biomass is commonly used for the production of bio-ethanol by a series of processes such as pretreatment, enzymatic degradation, and fermentation. Hemicellulose, constituting 20 wt-% - 40 wt-% ofbiomass materials, contains various kinds of saccharides known to be bioactive substrates. Practical usage of hemicellulose is generally limited to its conversion to bio-ethanol. Here, we aimed to prepare hemicellulolic oligosaccharides, more valuable products other than ethanol. Therefore, the Hinoki slurry was treated with lime at room temperature for 3 h, and then neutralized with HCI. The resulting sample was treated with 13 types of commercial enzymes, and the saccharides produced in the supernatant were evaluated. The result showed that the commercial enzyme Cellulase SS （Nagase ＆ Co., LTD.） effectively degraded the slurry to produce disaccharides and trisaccharides. Analysis of sugar components by liquid chromatography/mass spectrography （LC/MS） after the derivation with ethyl 4- aminobenzoate （ABEE） showed that mannobiose, manno- Nose, and cellobiose were the major oligosaccharides. These results indicate valuable oligosaccharides can be successfully produced from Hinoki softwood slurry.
基金Project supported by the National Science Foundation (Nos.DMS 06-04420 (RLP),DMS 08-11177(JGL))the Center for Nonlinear Analysis (CNA) under National Science Foundation Grant (Nos.0405343,0635983)
文摘The authors establish error estimates for recently developed finite-element methods for incompressible viscous flow in domains with no-slip boundary conditions.The methods arise by discretization of a well-posed extended Navier-Stokes dynamics for which pressure is determined from current velocity and force fields.The methods use C1 elements for velocity and C0 elements for pressure.A stability estimate is proved for a related finite-element projection method close to classical time-splitting methods of Orszag,Israeli,DeVille and Karniadakis.
