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21.
22.
Ohne Zusammenfassung
Kurzfassung eines Vortrags der 42. Fachtagung der ?sterreichischen Gesellschaft für Energietechnik (OGE) im OVE, die am 21.
und 22. Oktober 2004 in Graz stattfindet. 相似文献
23.
Pentane production by peanut lipoxygenase 总被引:1,自引:0,他引:1
Pentane and hexanal were the major volatile end-products of a peanut lipoxygenase and linoleic acid model system and were produced by both crude and purified enzyme preparations. The enzyme system did not require an anerobic condition for the production of pentane and hexanal, thus distinguishing it from other reported systems. A 122-fold purification of the enzyme was achieved. 相似文献
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This article describes an interactive prototyping model for development of four computer software modules for British youth on sexual issues. An iterative cycle of development, user review and feedback, and subsequent modification and retesting was used with approximately 150 young adults, with particular attention to presentation style, screen design, usability, relevance of material, enjoyment, and learning. The software was designed to be realistically accommodated in school settings, to be used as a reference tool by students working alone or in a group teaching situation. Feedback from youth and adults attests to the feasibility of development, implementation, and instructional usefulness. Interactive prototyping proved essential in the face of skepticism from teachers concerning young people's information needs and acceptance of a computerized educational approach. 相似文献
27.
Peanut lipoxygenase isozyme 1 (pH optimum, 8.3) was strongly activated by 0.5–1.0 mM Ca++, and the rate of activation was maximum when the ratio of substrate to Ca++ was ca. 2∶1. Peanut lipoxygenase isozymes 2 and 3 (pH optima, 6.2) were activated by calcium but did not have an optimum
level of activity. Calcium differentially activated peanut lipoxygenase causing the rate of pentane production to increase
much more rapidly than the rate of oxygen consumed by the enzyme reaction. At pH 6.2, in the absence of calcium, the percentages
of the hydroperoxide isomers produced by peanut lipoxygenase were 74.9% 13-hydroperoxycis-9,trans-11-octadecadienoic acid (13 LOOHcis-trans), 2.6% 13-hydroperoxytrans-9,trans-11-octadecadienoic acid (13 LOOHtrans-trans) and 22.5% 9-hydroperoxy 10, 12-octadecadienoic acid (9 LOOH). The presence of 1 mM Ca++ at pH 6.2 did not significantly affect the percentage distribution of the hydroperoxides produced. However, at pH 8.3, the
percentage distribution of hydroperoxides produced was 45.2% 13 LOOHcis-trans, 10.9% 13 LOOHtrans-trans and 43.9% 9 LOOH in the absence of Ca++ and 57.0% 13 LOOHcis-trans, 8.0% 13 LOOHtrans-trans and 35.0% 9 LOOH in the presence of 1 mM Ca++.
Paper No. 5110 of the Journal of the North Carolina Agricultural Experiment Station, Raleight, NC 27607. 相似文献
29.
Summary The practical limits of the solubility of pure monostearin in various solvents at different temperatures has been determined
for isopropyl alcohol, ethanol, acetone, methanol, and commercial hexane. The synthetic method was employed, in which the
temperature of known quantities of solvent and solute was decreased until crystallization of the solute began. This temperature,
corrected for supercooling and heat loss to the surrounding bath, was taken as the equilibrium temperature between the known
weight of solute and the known weight of solvent.
The solubility-temperature data of monostearin in each of the various solvents are presented both graphically and in tabular
form.
A comparison of the solubility of monostearin in the various solvents at comparative temperatures indicates that its solubility
is greatest in isopropyl alcohol and decreases in the order ethanol, acetone, methanol, and hexane.
Presented at the 45th annual meeting of the American Oil Chemists' Society, San Antonio, Tex., April 12–14, 1954.
One of the laboratories of the Southern Utilization Research Branch, Agricultural Research Service, U. S. Department of Agriculture. 相似文献
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