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51.
Ethylamine is selectively produced in the amination of ethanol with ammonia over Hu5775676307/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0"> zeolite. 相似文献
52.
Reinvestigation confirms action of Δ11-desaturases in spruce budworm moth sex pheromone biosynthesis
The biosynthesis of a large number of sex pheromone components of various moth species has been shown to start with common fatty acids and involve chain shortening by two carbons and introduction of a double bond at the 11–12 position. A recent report indicates that one of these common components, (E)-11-tetradecenyl acetate, is present in the eastern spruce budworm,Choristoneurafumiferana, but is not made by this pathway. Reinvestigation of this insect using in vivo and in vitro techniques indicates that the acetate indeed is made by a sequence of reactions similar to that used in other leafroller moths. In fact, evidence was found for the presence of several u73u41l8/xxlarge916.gif" alt="Delta" align="BASELINE" BORDER="0">11-desaturase systems in spruce budworm. One produced a large quantity of (Z)-11-hexadecanoic acid, and another produced (E)-11-tetradecanoic acid. It is not known if the small amount of (Z)-11-tetradecanoic acid is produced by either of those two systems or by a third system. A comparison with other species showed that cabbage looper moths have only the first system, redbanded leafroller moths use the last two systems, and European corn borer moths have all three. 相似文献
53.
K. S. Boo I. B. Chung K. S. Han J. A. Pickett L. J. Wadhams 《Journal of chemical ecology》1998,24(4):631-643
The lacewing Chrysopa cognata, one of the principal predators of aphids in Korea, was tested for responses to the aphid sex pheromone components (4aS,7S,7aR)-nepetalactone and (1R,4aS,7S,7aR)-nepetalactol and the aphid alarm pheromone (E)-u/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">-farnesene. Electroantennogram responses were obtained to the sex pheromone components but not to (E)-u/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">-farnesene. The sex pheromone components were attractive in a Y-tube olfactometer assay and in field trials with water traps, but no attraction was observed to (E)-u/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">-farnesene. 相似文献
54.
对达拉特~丰镇输电线路工程的铁塔基础做了模型试验 ,测试了土中位移、破坏形式、土中应力分布 ,应用软件ALGORFEAS ,得出了土体上拔时的应力场分布 ,并提出了强度机理及极限上拔力的计算方法。 相似文献
55.
56.
铸造镍基高温合金中的初生μ相 总被引:3,自引:1,他引:2
研究了铸造镍基高温合金中初生μ相的形成条件及μ相的特征,结果表明:在碳量低于0.07%的铸造镍基高温合金中,当难熔元素Cr,Mo,W,Nb,Hf总量超过11%超过8%,Mo/(W+Mo)(原子分数)超过0.17时会形成初生μ相,该相在高温下是不稳定的,它会转变成M6C碳化物。Mo,W,CrHf,Nb,Co是μ相形成元素,Mo在形成μ相方面作用更强,W,Cr,Hf,Nb的作用差别不明显,Co的作用小 相似文献
57.
58.
Ein Notar kann beweiskr?ftig beurkunden, dass ein Super?difikat nicht mehr besteht. Durch die Vorlage einer solchen Urkunde
wird dem Grundbuchsgericht bekannt, dass das selbst?ndige Eigentum am Bauwerk untergegangen ist. Es hat diesfalls die Ersichtlichmachung
des Bauwerks im Grundbuch gem § 19 Abs 3 UHG zu l?schen. Verweigert das Grundbuchsgericht die L?schung, kann der Liegenschaftseigentümer
dagegen Rekurs erheben. 相似文献
59.
Kazumi Ikeda Richard A. Kochendarfer Shigeru Kunishima 《Nuclear Engineering and Design》2011,241(5):1438-1453
This paper presents about conceptual designs of Advanced Recycling Reactor (ARR) focusing on enhancement in transuranics (TRU) burning and americium (Am) transmutation. The design has been conducted in the context of the Global Nuclear Energy Partnership (GNEP) seeking to close nuclear fuel cycle in ways that reduce proliferation risks, reduce the nuclear waste in the US and further improve global energy security. This study strives to enhance the TRU burning and the Am transmutation, assuming the development of related technologies in this study, while the ARR based on mature technologies was designed in the previous study. It has followed that the provided TRU burning core is designed to burn TRU at 28 kg/TWub>thub>h, by adding moderator pins of Bub>4ub>C (Enriched B-11) and the Am transmutation core will be able to transmute Am at 34 kg/TWub>thub>h, by locating Am blanket of AmN around the TRU burning core. It indicates that these concepts improve TRU burning by 40-50% than the previous core and can transmute Am effectively, keeping the void reactivity acceptable. 相似文献
60.
Juana Frias Concepcion Vidal-Valverde Halina Kozlowska Ryszard Gorecki Johana Honke Clifford L. Hedley 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1996,203(1):27-32
Seeds of pea (Pisum sativum L. cv. Ergo), faba bean (Vicia faba ssp. minor Harz., cv. Tibo) and yellow pea lupin (Lupinus luteus L. cv. Juno) were sampled at different days after flowering (DAF) and their content of soluble carbohydrates was determined: Analysis of samples showed thatmyo-inositol, fructose, glucose, galactose and sucrose were found in high abundance early in development and their content decreased gradually during maturation. u1557g5v7q112707/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">-Galactosides, which includes the content of raffinose, stachyose and verbascose, started to appear later in seed development, at 37 DAF in peas, 40 DAF in faba beans and 45 DAF in lupins. Their accumulation increased considerably during seed growth, and the maximum content was obtained in mature seeds; 3.8% in peas, 4.5% in faba beans and 10.4% in lupins. Results obtained for these sugars during seed development were fitted to modelling curves in order to predict sugar content at different development stages. 相似文献