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排序方式: 共有105条查询结果,搜索用时 93 毫秒
1.
Rivard C. J. Himmel M. E. Vinzant T. B. Adney W. S. Wyman C. E. Grohmann K. 《Applied biochemistry and biotechnology》1989,(1):461-478
Economic evaluations of the capital costs for anaerobic digestion systems for gas production show that the reactor is a significant
cost component. The successful application of high solids digestion of processed MSW (e.g., greater than 10% solids within
the digester) would allow a decrease in reactor volume with maintenance of relatively high gas production rates. However,
high solids slurries do not mix well in conventional stirred tank reactors. A horizontal shaft, hydraulically driven reactor
was designed and fabricated to test the anaerobic digestion of high solids concentrations. Digester performance was evaluated
as a function of experimental parameters such as nutrient requirements, feeding rates, pH control, and agitator design/ rotation
speed; horsepower of mixing was also evaluated for the reactor. Several startup protocols were examined to obtain a biologically
stable anaerobic fermentation at high solids levels. 相似文献
2.
Spindler Diane D. Wyman Charles E. Grohmann Karel 《Applied biochemistry and biotechnology》1991,(1):773-786
Four promising woody crops (Populusmaximowiczii x nigra (NE388), P.trichocarpa x deltoides (Nll), P.tremuloides, and SweetgumLiquidambar styraciflua) were pretreated by dilute sulfuric acid and evaluated in the simultaneous saccharification and fermentation (SSF) process
for ethanol production. The yeastSaccharomyces cerevisiae was used in the fermentations alone, and in mixed cultures with β -glucosidase producingBrettanomyces dausenii. Commercial Genencor 150L cellulase enyme was either employed alone or supplemented with β- glucosidase. All SSFs were run at 37 …C for 8 d and compared to saccharifications at 45…C under the same enzyme loadings.S. cerevisiae alone achieved the highest ethanol yields and rates of hydrolysis at the higher enzyme loadings, whereas the mixed culture
performed better at the lower enzyme loadings without β -glucosidase supplementation. The best overall rates of fermentation
(3 d) and final theoretical ethanol yields (86–90%) were achieved with P.maximowiczii x nigra (NE388) and SweetgumLiquidambar styraciflua, followed by P.tremuloides and P.trichocarpa xdeltoides (N1l) with slightly slower rates and lower yields. Although there were some differences in SSF performance, all these pretreated
woody crops show promise as substrates for ethanol production. 相似文献
3.
Grohmann K. Mitchell D. J. Himmel M. E. Dale B. E. Schroeder H. A. 《Applied biochemistry and biotechnology》1989,(1):45-61
Xylan backbones in native plant cell walls are extensively acety-lated. Previously, no direct investigations as to their role
in cellulolytic enzyme resistance have been done, though indirect results point to their importance. An in vitro deesterification
of aspen wood and wheat straw has been completed using hydroxylamine solutions. Yields of 90% acetyl ester removal for both
materials have been accomplished, with little disruption of other fractions (i.e., lignin). Apparently, as the xylan becomes
increasingly deacetylated, it becomes 5–7 times more digestible. This renders the cellulose fraction more accessible, and
2–3 times more digestible. This effect levels off near an acetyl removal of 75%, where other resistances become limiting. 相似文献
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John P. Boyd Maria Schlangen Andreas Grohmann Helmut Schwarz 《Helvetica chimica acta》2008,91(8):1430-1434
An unprecedented alkyne–nitrile metathesis takes place when the high‐valent iron‐nitrido dication [Fe(L)N]2+, with L=2,6‐bis(2‐methyl‐1,3‐diaminopropan‐2‐yl)pyridine, is reacted with alkynes in the gas phase under thermal conditions. While the detailed role of the alkyne substrate with respect to relative rates, regioselectivities, and branching ratios remains to be elucidated, the very existence of this novel metathesis reaction provides additional experimental evidence of a genuine, long‐lived, formal iron(V)‐nitrido dication. 相似文献
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Torget R. Werdene P. Himmel M. Grohmann K. 《Applied biochemistry and biotechnology》1990,24(1):115-126
Applied Biochemistry and Biotechnology - Large-scale production of ethanol or other transportation fuels by biological conversion of lignocellulosic biomass will eventually require integration with... 相似文献
10.
Rakshit S Grohmann C Besset T Glorius F 《Journal of the American Chemical Society》2011,133(8):2350-2353
An efficient Rh(III)-catalyzed oxidative olefination by directed C-H bond activation of N-methoxybenzamides is reported. In this mild, practical, selective, and high-yielding process, the N-O bond acts as an internal oxidant. In addition, simply changing the substituent of the directing/oxidizing group results in the selective formation of valuable tetrahydroisoquinolinone products. 相似文献