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131.
The production cost of cellulolytic enzymes is a major contributor to the high cost of ethanol production from lignocellulosics
using enzymatic hydrolysis. The aim of the present study was to investigate the cellulolytic enzyme production ofTrichoderma reesei Rut C 30, which is known as a good cellulase secreting micro-organism, using willow as the carbon source. The willow, which
is a fast-growing energy crop in Sweden, was impregnated with 1–4% SO2 and steam-pretreated for 5 min at 206°C. The pretreated willow was washed and the wash water, which contains several soluble
sugars from the hemicellulose, was supplemented with fibrous pretreated willow and used for enzyme production. In addition
to sugars, the liquid contains degradation products such as acetic acid, furfural, and 5-hydroxy-methylfurfural, which are
inhibitory for microorganisms. The results showed that 50% of the cellulose can be replaced with sugars from the wash water.
The highest enzyme activity, 1.79 FPU/mL and yield, 133 FPU/g carbohydrate, was obtained at pH 6.0 using 20 g/L carbon source
concentration. At lower pHs, a total lack of growth and enzyme production was observed, which probably could be explained
by furfural inhibition. 相似文献
132.
Fenyvesi Éva Nagai Tsuneji Antal Balázs Zsadon Béla Szejtli József 《Journal of inclusion phenomena and macrocyclic chemistry》1984,2(3-4):645-654
Cyclodextrin polymer was compared to other well known disintegrants concerning the swelling properties /water uptake, moisture uptake, hydration capacity, sedimentation volume in water/. Its high disintegrating effect was proved in directly compressed tablets as well as in tablets made by wet granulation. A remarkable improvement in tablet properties was observed. Not only the disintegration of tablets and the dissolution of the drug was accelerated but also the hardness increased when CDP was used as disintegrant. 相似文献
133.
L. Moens F. De Corte A. De Wispelaere J. Hoste A. Simonits A. Elek E. Szabo 《Journal of Radioanalytical and Nuclear Chemistry》1984,82(2):385-452
Recommended k0-factors and related nuclear data for use in (n, γ) activation analysis are given for 72 isotopes. In addition the basic nuclear constants and experimental parameters needed in the k0 standardization method are reviewed. For convenient data reduction, computer programs were developed. 相似文献
134.
V. M. Leovac E. Z. Ivegeš K. Mészáros Szécsényi K. Tomor G. Pokol S. Gal 《Journal of Thermal Analysis and Calorimetry》1997,50(3):431-440
Solvate complexes of UO 2 2+ andN(1), N(4)-bis(salicylidene)-S-methylisothiosemicarbazone, (H2Me-L1), of general formula [UO2(Me-L1)S] (S= H2O, MeOH, EtOH, Py, DMF and DMSO) were synthesized. The methanolic UO 2 2+ ” adducts of N(1)-benzoylisopropylidene-N(4)-salicylidene-S-alkylisothiosemicarbazone, (H2R-L2,R=Me, Prn) of general formula [UO2(R-L2)· MeOH], were also prepared. Thermal decomposition of the complexes was investigated in air and argon. The complexes decompose to α-U3O8 in air, while in argon the decomposition is not completed up to 1000 K. The temperature and the mechanism of decomposition of the complexes are a function of the solvent belonging to the inner coordination sphere. 相似文献
135.
Quinolizidines containing an exocyclic double bond at C-2 (1,2) give on mild oxidation the amino dienes (3,4), as mixtures of geometric isomers with respect to the exocyclic double bond. The free enthalpy of activation for the rotation about the double bond has been estimated by NMR. 相似文献
136.
L. Erdey und G. Svehla 《Fresenius' Journal of Analytical Chemistry》1959,167(3):164-172
Zusammenfassung Als Fortsetzung einer früheren Mitteilung10 wird über die indirekte ascorbinometrische Bestimmung von freien Halogenen, Hypochloriten, Hypobromiten, Chloriten, Bromaten, Jodaten und Chloramin T berichtet. Die Lösung dieser Oxydationsmittel wird mit überschüssigem Kaliumhexacyanoferrat(II) versetzt und die entstehenden Hexacyanoferrat(III)ionen werden in Anwesenheit von 2,6-Dichlorphenolindophenol-Indicator mit Ascorbinsäuremaßlösung titriert.I.Mitteilung: diese Z. 163, 6 (1858).Teil der Dissertation von G. Svehla, Budapest, Technische Universität, 1959. 相似文献
137.
S. Mlinkó I. Gács K. Payer J. Ottinger E. Dobis 《Journal of Radioanalytical and Nuclear Chemistry》1977,35(2):321-331
In this paper an automatic apparatus designed for the radioactivity measurement of14C-labelled organic compounds in the gaseous phase is described. The labelled organic compounds are combusted in a mixture
of argon and oxygen. After combustion the oxygen content of the gas is eliminated by passing it through a copper packing.
The water and heteroelements present are also removed and the radioactive carbon dioxide gas is swept by argon carrier gas
into a piston-type counter tube. In the counter tube the piston forming a dividing wall moves forward in accordance with the
rate of combustion and sweeping, and thus sucks the gases leaving the combustion tube into the effective tube volume. The
anode wire is carried by a reel located in the piston and a spring device ensures its stretched state. At the end of the sweeping
period methane is fed into the counter tube and the activity of the argon—methane—carbon dioxide mixture is measured in the
limited proportional region. Manual and automatic operation is possible. The piston-type counter tube provides possibility
for strandardization by means of extrapolation and for measurement of absolute activities. 相似文献
138.
A mordenite-containing rock from the Tokaj-mountains was investigated. The effect of the treatment with hydrochloric acid solutions of various molarity was established. From gas adsorption measurements, scanning electron microscopic investigations and measurements with a mercury porosimeter conclusions were drawn on the changes caused by acid treatment. Slight changes in the texture were found, but no damage in the crystal structure could be observed.
- . . , - , , . - .相似文献
139.
The effect of substituted hydroxybenzophenone, benzotriazole and organic metal complexes on the photooxidation of PP films has been studied. It has been established that NiDBTC added in 1.0 wt. % is the most effective photostabilizer.While in the case of other stabilizers there is a slight increase in the Co content even during the induction period, with the application of NiDBTC practically no oxidation can be observed before the stabilizer completely disappears. This means that NiDBTC inhibits the photooxidation of the polymer even in low concentration.
, - . , Ni, 1,0 . %. . , Ni , . , Ni .相似文献
140.
M. Nagy 《Colloid and polymer science》1985,263(3):245-265