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11.
Es wurde eine Laboreinrichtung zur kontiniuerlichen Aktivierungsanalyse strömender, Flüssigkeiten entworfen und gebaut. Die Einrichtung bestecht aus dem Vorratsbehälter für die Probelösung, der Aktivierungskammer, einer Pu-Be-Neutronenquelle, der Meβkammer, der Meβeinrichtung, einer Laborpumpe und einem Strömungsmesser. Die vorläufigen Versuche bewiesen, daβ mit der gebauten Einrichtung die Bestimmung von Vanadium, Silber and Kobalt möglich ist.  相似文献   
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There is a desire to alter food composition to make foods healthier and at the same time not diminish sensory quality. This requires an understanding of key elements of food structure associated with texture perception. Texture, in part, is perceived during oral processing of food. Knowledge of structure–oral processing–texture interrelations could be utilized to develop or prevent specified textural attributes. Overall, the investigation of structure–oral processing–texture interrelations is just starting as a research focus. Factors including non-universal and inconsistent sensory terminology, omission of consideration for structural changes incurred by oral processes, and the lack of cross-disciplinary investigations hamper progress in this field. Consideration of these factors in future investigations on sensory texture will increase the applicability of their findings and bring us closer to understanding the contribution of food structure to sensory texture.  相似文献   
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Chemistry of Natural Compounds - A new seco-abietanoid, 12-methoxy-7-oxo-6,7-secoabieta-8,11,13-trien-6-oic acid (1), and a known seco-abietanoid,12-hydroxy-6,7-secoabieta-8,11,13-triene-6,7-dial...  相似文献   
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Journal of Inclusion Phenomena and Macrocyclic Chemistry - Stability of inclusion complexes of thymol (a natural flavour) with cucurbit[n]urils was interpreted by using density functional theory...  相似文献   
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An efficient and practical Pd‐catalyzed intramolecular oxidative allylic amidation provides facile access to derivatives of 1,3‐ and 1,4‐amino alcohols and 1,3‐diamines. The method operates under mild reaction conditions (RT) with molecular oxygen (1 atm) as the sole reoxidant of Pd. Excellent diastereoselectivities were attained with substrates bearing a secondary stereogenic center  相似文献   
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Polypyrrole, formed in an organic solvent, shows higher density and better quality in electrical conductivity and mechanical strength than that formed in water. On electrochemical reduction in an aqueous system the laurylsulfate anion, used as dopant, sticks to the polymer. During reduction a cation moves into the polymer and on oxidation it leaves the polymer. The anion, however, leaves the polymer on reduction in an organic solvent system and cannot penetrate into the polymer on re-oxidation. The redox reaction in the aqueous system reveals a surface reaction process, while the reaction in the organic solvent system undergoes a diffusion-controlled process. This penomenon is consistant with the results of the ion concentration profile.  相似文献   
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Michelia formosana (Kanehira) Masamune is a broad-leaved species widespread in East Asia; the wood extract and its constituents possess antifungal activity against wood-decay fungi. Antifungal activities of leaf essential oil and its constituents from M. formosana were investigated in the present study. Bioassay-guided isolation was applied to isolate the phytochemicals from leaf essential oil. 1D and 2D NMR, FTIR, and MS spectroscopic analyses were applied to elucidate the chemical structures of isolated compounds. Leaf essential oil displayed antifungal activity against wood decay fungi and was further separated into 11 fractions by column chromatography. Four sesquiterpenoids were isolated and identified from the active fractions of leaf essential oil through bioassay-guided isolation. Among these sesquiterpenoids, guaiol, bulnesol, and β-elemol have higher antifungal activity against brown-rot fungus Laetiporus sulphureus and white-rot fungus Lenzites betulina. Leaf essential oil and active compounds showed better antifungal activity against L. sulphureus than against L. betulina. The molecular structure of active sesquiterpenoids all contain the hydroxyisopropyl group. Antifungal sesquiterpenoids from M. formosana leaf essential oil show potential as natural fungicides for decay control of lignocellulosic materials.  相似文献   
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