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91.
Nasib Qureshi Patrick Karcher Michael Cotta Hans P. Blaschek 《Applied biochemistry and biotechnology》2004,114(1-3):713-721
Corn steep liquor (CSL), a byproduct of the corn wet-milling process, was used in an immobilized cell continuous biofilm reactor
to replace the expensive P2 medium ingredients. The use of CSL resulted in the production of 6.29 g/L of total acetone-butanol-ethanol
(ABE) as compared with 6.86 g/L in a control experiment. These studies were performed at a dilution rate of 0.32 h−1. The productivities in the control and CSL experiment were 2.19 and 2.01 g/(L·h), respectively. Although the use of CSL resulted
in a 10% decrease in productivity, it is viewed that its application would be economical compared to P2 medium. Hence, CSL
may be used to replace the P2 medium. It was also demonstrated that inclusion of butyrate into the feed was beneficial to
the butanol fermentation. A control experiment produced 4.77 g/L of total ABE, and the experiment with supplemented sodium
butyrate produced 5.70 g/L of total ABE. The butanol concentration increased from 3.14 to 4.04 g/L. Inclusion of acetate in
the feed medium of the immobilized cell biofilm reactor was not found to be beneficial for the ABE fermentation, as reported
for the batch ABE fermentation.
Names are necessary to report factually on available data. However, the USDA neither guarantees nor warrants the standard
of the product, and the use of the names by USDA implies no approval of the product to the exclusion of others that may also
be suitable. 相似文献
92.
Rate constants for the reaction of ethyl bromoacetate with three series of substituted naphthoate ions have been measured
in an acetone-water mixture (90% v/v). Using σ
p
values rate constants at 30o correlate well with the Hammett equation yielding ρ=−0.54, −0.19 and −0.25 for (4,1−), (6,1−) and (6,2−) series, respectively.
Comparison of these ρ values with those of the reaction of phenacyl bromide reveals the failure of the reactivity-selectivity
principle RSP in these reactions. Failure of RSP has been explained in terms of isoselective temperature. 相似文献
93.
ChangLuSHAO HongYuGUAN ShangBinWEN BinCHEN XingHuaYANG JianGONG YiChunLIU 《中国化学快报》2004,15(4):492-494
Thin PVA/cobalt acetate composite fibers were prepared by using sol-gel processing and electrospinning technique.After calcination of the above precursor fibers,Co3O4 nanofibers with a diameter of 50-150 nm could be successfully obtained.The fibers were characterized by SEM,FT-IR,WAXD,respectively. 相似文献
94.
An efficient solution-processable route employing Pb(Ac)2 as lead source and anti-solvent treatment to achieve fully covered and homogenous perovskite films is reported. 相似文献
95.
96.
Bis- as well as tris-tetrahydropyranone ring systems were obtained via multiple tandem cyclization-1,3-dipolar cycloaddition reactions of α-diazo ketones with ketone as well as aldehyde functional groups in a chemoselective manner. 相似文献
97.
Christophe Hoarau Alexis Du Fou de Kerdaniel Pierre Grandclaudon Francis Marsais 《Tetrahedron letters》2005,46(49):8573-8577
The efficient and regioselective palladium-catalyzed C-2 arylation of ethyl 4-oxazolecarboxylate 1 with phenyliodide is described. The different parameters (solvent, base, ligand and catalyst) for the optimal conditions of this arylation process have been screened. 相似文献
98.
Copolymers of ethyl cellulose (EC) with polystyrene (PSt) were synthesized through atom transfer radical polymerization (ATRP). The molecular weight of graft copolymers increased without any trace of the EC macro-initiator, and the polydispersity of the side chains was low. The molecular weight of the side chains increased with the monomer conversion. Kinetic study indicated that the polymerization was first order. The micelle characteristics of the graft copolymer in acetone were investigated using dynamic light scattering (DLS), atom force microscopy (AFM) and transmission electron microscopy (TEM). With increasing the concentration, micelles were gradually formed from the solution. The TEM and AFM images indicated that the micelles had spherical shape and showed core-shell structure. 相似文献
99.
A. A. Vasil'ev A. L. Vlasyuk G. V. Kryshtal E. P. Serebryakov 《Russian Chemical Bulletin》1995,44(10):1946-1951
Stereospecific syntheses of (±)-3-methyl-6-isopropenyl-3(Z),9-decadien-1-yl acetate and (±)-3,9-dimethyl-6-isopropenyl-3(Z),9-decadien-1-yl propionate (the Racemoc forms of the pheromones of the scalesAonidiella aurantii andPseudaulascaspis pentagona) with a geometrical purity of the (Z)-trisubstituted double bond not lower than 99 % were performed. The key step in both syntheses was the 1,4-cis-hydrogenation of the corresponding ethyl 3-methyl-6-(1, 1-ethylenedioxyethyl)-2,4,9-decatrienoates catalyzed with chromium carbonyl complexes. These 2,4-dienes were obtained in five conventional steps including the alkylation of ethyl acetoacetate by the appropriate 1-bromo-3-butenes and the Horner-Emmons olefination of the corresponding -branched aldehydes.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2026–2031, October, 1995. 相似文献
100.