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Software and Systems Modeling - Engineers commonly use paper and whiteboards to sketch and discuss ideas in early phases of requirements elicitation and software modeling. These physical media... 相似文献
43.
Norbert Fischer Siegfried Nitz und Friedrich Drawert 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1987,185(3):195-201
Zusammenfassung In grünem (Taiwan Gunpowder) und schwarzem (Ceylon high OP) Tee sind beträchtliche Mengen an Aromastoffen in glykosidischer Bindung vorhanden; ihr Anteil ist sogar höher als der an freien Aromastoffen. Hauptkomponenten sind in beiden Teesorten cis-3-Hexen-1-ol, Benzylalkohol und 2-Phenylethanol in gebundener Form, dazu im Schwarztee Linalool und im grünen Tee Geraniol. Die unterschiedlichen Anteile dieser beiden Terpenalkohole spiegeln die unterschiedlichen Tee-Varietäten wieder, denen die untersuchten Teesorten angehören: der Ceylon-Tee ist der Varietätassamica zuzuordnen, der Tee aus Taiwan der Varietätsinensis. Die Zusammensetzung der aus gebundenen Formen freisetzbaren Aromastoffe war ähnlich komplex wie die der freien Aromastoffe, wobei die Unterschiede zwischen den beiden Teesorten auf den verschiedenen Herstellungsverfahren beruhen. Das Auftreten gebundener Formen solcher Aromastoffe, die nicht originär vorhanden sind, sondern erst während der Welk- oder der Fermentationsphase gebildet werden, impliziert das Vorhandensein glykosidierender Aktivitäten im Teeblatt noch in relativ späten Stadien der Schwarzteeherstellung. Die Untersuchung der gebundenen Anteile an Aromastoffen trägt neben der Analyse der freien Aromastoffe wesentlich zum Verständnis der Reaktionen im Teeblatt wahrend der verschiedenen Produktionsstadien bei.
Auszug aus der Dissertation von N. Fischer, Technische Universitat München 1986
1. Mitteilung Chem Mikrobiol Technol Lebensm 9:87 (1985) 相似文献
Bound flavour compounds in plants 2. Part. Free and bound flavour compounds in green and black tea
Summary Green and black tea contains considerable amounts of flavour compounds which are present in glycosidic bonds, their portion being even higher than that of free flavour compounds. The main components in both of these tea varieties are 3-hexene-1-ol, benzylalcohol and 2-phenylethanol, which are present in the bound forms, and additionally linalool in black tea and geraniol in green tea. The different amounts of these terpene alcohols reflect the different varieties the teas under investigation belong to: the Ceylon tea belongs to the variety assamica, and the Taiwan tea to the variety sinensis. The composition of the flavour compounds liberated from bound forms had a similar complexity to that of the free flavour compounds, the difference being based upon the different production procedures. The occurrence of bound forms of such components that are not originally present but are produced during the withering or fermentation stage implies that glycosidating activities are still present in the tea leaf, even in a relatively late stage of the black tea production process. The investigation of the bound parts of flavour compounds delivers a valuable contribution to a better understanding of the reactions occurring in the tea leaf during the different stages of tea production.
Auszug aus der Dissertation von N. Fischer, Technische Universitat München 1986
1. Mitteilung Chem Mikrobiol Technol Lebensm 9:87 (1985) 相似文献
44.
Contribution to the Biosynthesis of High-amylose Pea Starches Biosynthesis of starch is a complex process but few details are still unknown. This paper describes an investigation upon pea starch biosynthesis. Peas as a source of starch offer two qualities, a pea starch with 40% amylose content (smooth pea starch) and a pea starch with more than 60% amylose content (wrinkled pea starch). Samples for analysis were taken during growth. According to the quantitative determination of starch and amylose the accuracy of amylose detection was tested. Furthermore a qualitative analysis was carried out by molecular weight estimation of the starch. Both kinds of peas showed a high amylose synthesis during the last few days of growth, whereas amylopectin synthesis was highly in earlier stages. Wrinkled peas have shown only little synthesis activity of amylopectin during maturity. Therefore the amylose content of these peas was higher, instead of equal amylose synthesis quotas of both smooth and wrinkled peas. 相似文献
45.
46.
Signatures of a Two‐Dimensional Ferromagnetic Electron Gas at the La0.7Sr0.3MnO3/SrTiO3 Interface Arising From Orbital Reconstruction 下载免费PDF全文
47.
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Norbert Moszner Frank Zeuner Thomas Vlkel Urs Karl Fischer Volker Rheinberger 《应用聚合物科学杂志》1999,72(13):1775-1782
1,3‐Bis[(1‐alkoxycarbonyl‐2‐vinylcyclopropane‐1‐yl)carboxy]benzenes 1 [RO: CH3O (a), C2H5O (b)] were synthesized by the esterification of the corresponding 1‐alkoxycarbonyl‐2‐vinylcyclopropane‐1‐carboxylic acids with resorcinol. The structure of the new vinylcyclopropanes was confirmed by elemental analysis and infrared (IR), 1H nuclear magnetic resonance (1H‐NMR), and 13C nuclear magnetic resonance (13C‐NMR) spectroscopy. The radical polymerization of difunctional 2‐vinyl‐cyclopropanes in bulk with 2,2′‐azoisobutyronitrile (AIBN) results in hard, transparent, crosslinked polymers. During the bulk polymerization of the crystalline bis[(1‐methoxycarbonyl‐2‐vinylcyclopropane‐1‐yl)carboxy]benzene 1a, an expansion in volume of about 1% took place. The radical solution polymerization of 1a resulted in a soluble polymer with pendant 2‐vinylcyclopropane groups. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 72: 1775–1782, 1999 相似文献
49.
Marcus Heinze Sandra Starke Marcel Händler Hartmut Komber Marco Drache Norbert Moszner Brigitte Voit Doris Pospiech 《应用聚合物科学杂志》2019,136(48):48256
We demonstrate in this study that the combination of modern inline monitoring methods [here: inline nuclear magnetic resonance (NMR)] with simulations gains more exact and profound kinetic results than previously used methods like linearization without that combination. The 1H-NMR spectroscopic data (more than 100 data points) are used to construct the copolymerization diagram. The reactivity ratios are obtained applying the van Herks nonlinear least square method. The examination of the radical copolymerization of 2-hydroxyethyl methacrylate (HEMA) with (2-{[2-(ethoxycarbonyl)prop-2-en-1-yl]oxy}ethyl) phosphonic acid (ECPPA) as important adhesive monomer used in dentistry yields reactivity ratios of rHEMA = 1.83; rECPPA = 0.42. The copolymerization diagram reflects nonideal, non-azeotropic copolymerization. The sequence distribution of the obtained by Monte Carlo simulation indicates the generation of statistical copolymers. As an important finding, it is demonstrated that the repeating units responsible for etching and adhesion are arranged over the whole polymer chain, which is necessary to achieve proper functionality. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48256. 相似文献
50.
A millistructured reactor and spectroscopic setup for contactless kinetic measurements in oscillating droplets is presented in this work. The polymerization of acrylic acid serves as a model reaction. Design and construction of the reactor focus on the optical access for Raman measurement, the nearly isothermal behavior, and the preservation of droplets during long‐term reactions with a high increase of viscosity. Another key aspect is the possibility of full automation at a later stage. 相似文献