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81.
Werner Henning und Karl Herrmann 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1980,171(2):111-118
Zusammenfassung Blätter wie Früchte von 6 SortenPrunus domestica-Pflaumen enthalten hauptsächlich 3-Rutinoside, in geringerer Konzentration 3-Glucoside und 3-Galaktoside von Kämpferol und Quercetin Bowie Quercetin-3-rhamnosid. Dagegen weisen Pflaumen vonPrunus salicina (2 untersuchte Sorten) Kämpferol-3,7-bisrhamnosid und Kämpferol-3-arabinosyl-7-rhamnosid als Hauptflavonole auf. Hierdurch ist eine Unterscheidung beider Arten leicht and sicher mög-lich. Weiterhin konnten inSalicina-Pflaumen Kämpfe-rol-3-rutinosid sowie Quercetin-3-rhamnosid, -xylosid,-glucosid, -galaktosid, --l-arabinofuranosid and -rutinosid, auch Quercetin-7-rhamnosid and Kämpferol-7-glucosid nachgewiesen werden.Die Gesamtgehalte an Flavonolglykosiden lagen bei den untersuchten Pflaumensorten vonPrunus domestica (P. salicina) bei 2500–3340 (7170, 10350) ppm in Blättern and 20–52 (8, 24) in Früchten, jeweils bezogen auf Frischgewicht.
11. Mitt.: Henning W, Herrmann K (1980) Z Lebensm Unters Forsch 170:433–444
Auszug aus der Promotionsarbeit von W. Henning: Bestimmung der in Pflaumen, Kirschen, Pfirsichen and Aprikosen vorkommenden Flavonolglykoside unter Anwendung der Hochdruckflüssigkeitschromatographie. Diss. Univ. Hannover 1980 相似文献
Flavonol glycosides of plums of the species Prunus domestica L. and Prunus salicina lindley12. Phenolics of fruits
Summary Leaves and fruits from 6 cultivars ofPrunus domestica plums contain mainly 3-rutinosides; in smaller concentrations the 3-glycosides and 3-galactosides of kaempferol and quercetin as well as quercetin-3-rhamnoside are present. On the other hand, in plums ofPrunus salicina (2 examined cultivars) main flavonols are kaempferol-3,7-bisrhamnoside and kaempferol-3arabinosyl-7-rhamnoside. Due to the difference in composition, differentiation of these species will be easy and reliable. Additionally kaempferol-3-rutinoside and quercetin-3-rhamnoside, -xyloside,-glucoside, -galactoside, --l-arabinofuranoside and-rutinoside, and also quercetin-7-rhamnoside and kaempferol-7-glucoside could be detected inP. salicina plums. The total content of flavonol glycosides in the investigated plums ofPrunus domestica (P. salicina) were based on fresh weight about 2500–3340 (7170, 10350) ppm in the leaves and 20–52 (8, 24) ppm in the fruits.
11. Mitt.: Henning W, Herrmann K (1980) Z Lebensm Unters Forsch 170:433–444
Auszug aus der Promotionsarbeit von W. Henning: Bestimmung der in Pflaumen, Kirschen, Pfirsichen and Aprikosen vorkommenden Flavonolglykoside unter Anwendung der Hochdruckflüssigkeitschromatographie. Diss. Univ. Hannover 1980 相似文献
82.
Werner Heimann und Verena Klaiber 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1977,165(3):131-136
Zusammenfassung Die Untersuchung einer aus Roggen gewonnenen Lipoxygenase-aktiven Enzymfraktion ergab, daß Roggenlipoxygenase ein Molekulargewicht von ca. 102000 besitzt. Bei der isoelektrischen Fokussierung traten zwei Bandengruppen mit isoelektrischen Punkten zwischen 5,1–5,5 und 5,8–6,4 auf. Durch Ionenaustauschchromatographie konnten drei Isoenzyme gewonnen werden. Das pH-Optimum der Umsetzung lag bei 7,3–7,5. Roggenlipoxygenase katalysiert vorwiegend die Bildung von 13-Hydroperoxy-9-cis,11-trans-octadecadiensäure (13-LHPO). Durch eine hochmolekulare Proteinfraktion wurden in Roggen die LHPO zu a-Ketolen umgesetzt. Diese Roggenisomerase setzt die von der systemeigenen Lipoxygenase gebildeten LHPO zu überwiegend 12,13-Ketohydroxysduren um. Roggenisomerase hat eine Michaeliskonstante von 3–5 × 10–5, (LHPO). Die Reaktionsgeschwindigkeit der Umsetzung stieg bei kleinen Proteinkonzentrationen linear mit der Proteinkonzentration.
On lipoxygenase and enzymes which decompose linoleic acid hydroperoxides in rye
Summary An enzyme fraction from rye containing lipoxygenase activity was investigated. The molecular weight of lipoxygenase was found to be about 102000. Two bands groups with isoelectric points between 5.1–5.5 and 5.8–6.4 were obtained by isoelectric focusing. Three isoenzymes could be separated by ion exchange chromatography. Lipoxygenase has optimum activity at pH 7.3–7.5 and predominantly forms 13-hydroperoxy-9-cis,11-trans-octadecadienoic acid (13-LHPO).In rye the 13-LHPO is converted to -ketols by a high molecular protein fraction. This isomerase converts the LHPO formed by rye lipoxygenase predominantly to 12,13-ketohydroxy acids. The Michaelis Constant of isomerase is 3–5 × 10–5, using LHPO as substrate. At low protein concentrations the reaction velocity of LHPO-conversion increases linearly with protein concentration.相似文献
83.
Adrian D. Werner Qi Zhang Lijuan Xue Brian D. Smerdon Xianghu Li Xinjun Zhu Lei Yu Ling Li 《Water Resources Management》2013,27(2):507-533
The state of groundwater systems worldwide is presently not well defined, and in particular there is little context for agencies responsible for managing water resources to evaluate occurrences of groundwater depletion against other cases globally. In this study, an initial inventory of groundwater depletion problems is compiled and ranked to identify the world’s most critical cases, i.e. situations of groundwater mega-depletion. The ranking is based on an indexed approach that considers overdraft, drawdown and subsidence, plus the importance of the resources in terms of population-dependency and rates of extraction. The five most highly ranked depleted aquifers of the world include the shallow aquifers of the Hai River Plain (China), the Altiplano region (Spain), the Mexico Basin (Mexico), the Huang River basin (China) and the California Central Valley (USA). An abridged account of modelling to assess drawdown is described for the Hai River Plain, revealing that despite recharge in the order of 13,000 GL/yr, an overdraft of about 8,000 GL/yr is occurring to support the vast population of the region. This has led to up to 100 m of drawdown in places and reports of subsidence of several metres. The Hai River situation demonstrates that falling water levels may not act to alleviate pumping stresses; a symptom of unchecked extraction and an exemplary illustration of the tragedy of the commons. The causal factors leading to mega-depletion are varying across the globe and each mega-depletion case contains unique elements, although population appears to be an important factor. 相似文献
84.
Christopher Martius Hubert Höfer Marcos V.B. Garcia Jörg Römbke Werner Hanagarth 《Nutrient Cycling in Agroecosystems》2004,68(2):137-154
The sustainability of agroforestry systems in Amazonia was assessed from their litter dynamics and decomposition. Litter fall and litter stocks were determined from July 1997 to March 1999 in four sites in central Amazonia: a primary rainforest, a 13-year-old secondary forest, and two sites of a polyculture forestry system which consisted of four planted tree species of commercial use amidst upcoming secondary growth. The average annual litter fall in the undisturbed primary rainforest (FLO) was 8.4 t ha–1 year–1, which is within the range of litter fall in other rainforests in the region. It was similar in one of the two polyculture sites (8.3 t ha–1 year–1), but lower in the secondary forest and in the second polyculture site. In the litter fall in secondary forest and agroforestry sites, the leaf portion was higher (76–82% of total litter fall) than in FLO, due to reduced fine matter and wood fall. Leaf litter fall variability was much lower in the plantation sites than in the forests, which is explained by the much more homogeneous stand structure of the plantations. The quality of the produced litter, measured as C/N ratio, differed significantly between the primary forest site and one polyculture and the secondary forest site. The cumulative input of nitrogen through litter fall was 144 kg ha–1 year–1 in FLO, and 91–112 kg ha–1 year–1 in the polycultures and the secondary forest. Litter fall was not correlated with soil parameters, but had a significant linear regression with canopy closure. For the primary rainforest, litter fall was also (inversely) correlated with monthly rainfall. Litter fall was higher in the first year (1997–1998; an El Niño period) than in 1998–1999. Litter stocks on the forest floor were highest in the secondary forest (24.7 t ha–1), and much lower in the polyculture sites (15.1–16.2 t ha–1) and the primary forest (12.0 t ha–1). There were no differences in the relative N content (C/N ratio) of the litter stocks between the sites, but the larger stocks led to higher absolute N contents in the litter layer in the secondary forest. From the monthly values of litter stocks (S) and litter fall (P), the decomposition coefficient k
e=P/S was calculated, which was, on average, highest for the primary forest (0.059), followed by the polyculture systems (0.040–0.042), and by the secondary forest (0.024). Thus, due to low decomposition rates, the secondary forest site showed large litter accumulations in spite of a relatively low litter fall. In contrast, the primary forest showed high litter fall but low stocks, due to high decomposition rates. The decomposition coefficients of the polyculture systems ranged between the primary and the secondary forest. The reduced decomposition rates in the man-managed agroecosystems indicate quantitative and/or qualitative changes in the decomposer communities of these systems that lead to a higher build-up of litter stocks on the forest floor. However, the decomposer systems in the polyculture sites still were more functional than in the site of non-managed secondary growth. Thus, from a soil biological viewpoint, ecologically sustainable low-input agroforestry in Amazonia will benefit from the application of these polyculture systems. 相似文献
85.
A group of 344 cervices, produced by conisation within a period of 5 1/2 years, were examined for specific effects of contraceptives. In half of all women, who used oral contraceptives, specific lesions such as "siebartige polypoide Hyperplasie" (cribriform polypoid hyperplasia) were found. The findings and their etiology and importance are discussed. 相似文献
86.
Frank Schilder Werner Vogt Stephan Schreiber Hinke M. Osinga 《International journal for numerical methods in engineering》2006,67(5):629-671
Quasi‐periodic oscillations and invariant tori play an important role in the study of forced or coupled oscillators. This paper presents two new numerical methods for the investigation of quasi‐periodic oscillations. Both algorithms can be regarded as generalizations of the averaging and the harmonic (spectral) balance methods. The algorithms are easy to implement and require only minimal a priori knowledge of the system. Most importantly, the methods do not depend on an a priori co‐ordinate transformation. The methods are applied to a number of illustrative examples from non‐linear electrical engineering and the results show that the methods are efficient and reliable. In addition, these examples show that the presented algorithms can also continue through regions of sub‐harmonic (phase‐locked) resonance even though they are designed only for the quasi‐periodic case. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
87.
88.
Nicole Altvater-Mackensen Gregor Balicki Lucie Bestakowa Bianca Bocatius Johannes Braun Lars Brehmer Verena Brune Kirstina Eigemeier F&#;sun Erdem Ralf Fritscher Anne Jacobs Bernd Klingsporn Marcin Kosinski Julia Kuntze Ju-Ra Lee Anna Osterhage Martin Probost Thorsten Risch Tobias Schmitt Wolfgang G. Stock Anja Sturm Katrin Weller Kerstin Werner 《Scientometrics》2005,63(3):463-529
Summary We operationalize scientific output in a region by means of the number of articles (as in the SciSearch database) per year and technology output by means of the number of patent applications (as in the database of the European Patent Office) per priority year. All informetric analyses were done using the DIALOG online-system. The main research questions are the following: Which scientific and technological fields or topics are most influent within a region and which institutions or companies are mainly publishing articles or holding patents? Do the distributions of regional science and technology fields and of publishing institutions follow the well-known informetric function? Are there - as it is expected - only few fields and few institutions which dominate the region? Is there a connection between the economic power of a region and the regional publication and patent output? Examples studied in detail are seven German regions: Aachen, Düsseldorf, Hamburg, Köln (Cologne), Leipzig - Halle - Dessau, München (Munich), and Stuttgart. Three different indicators were used, science and technology attraction of a region (number of scientific articles and patents), science and technology intensity (articles and patents per 1,000 inhabitants), and science and technology density (articles and patents per 1 billion EURO gross value added). Top region concerning both attraction and intensity is Munich, concerning density it is Aachen. 相似文献
89.
Jatinder N. D. Gupta Frank Werner Gunnar Wulkenhaar 《International Transactions in Operational Research》2003,10(3):267-294
This paper considers two-machine open shop problems with secondary criteria where the primary criterion is the minimization of makespan and the secondary criterion is the minimization of the total flow time, total weighted flow time, or total weighted tardiness time. In view of the strongly NP-hard nature of these problems, two polynomially solvable special cases are given and constructive heuristic algorithms based on insertion techniques are developed. A strongly connected neighborhood structure is derived and used to develop effective iterative heuristic algorithms by incorporating iterative improvement, simulated annealing and multi-start procedures. The proposed insertion and iterative heuristic algorithms are empirically evaluated by solving problem instances with up to 80 jobs. 相似文献
90.
We have developed a self-consistent quantum mechanical Monte Carlo device simulator that takes electron transport in quantized states into consideration. Two-dimensional quantized states in MOSFET channels are constructed from one-dimensional solutions of the Schrödinger equation at different positions along the channel, and the Schrödinger and Poisson equations are solved self-consistently in terms of electron concentration and electrostatic potential distribution. The channel electron concentration, velocity and drain currents are calculated with the one particle Monte Carlo approach incorporating the intra-valley acoustic phonon and inter-valley phonon scattering mechanisms. This simulator was applied to a 70 nm n-MOSFET transistor, and we found that current mostly flows through the lowest subband and transport is quasi-ballistic near the source junction. To quantitatively estimate the performance of advanced devices, we have developed an inversion carrier transport simulator based on a full-band model. Our simulation method enables us to evaluate device characteristics and analyze the transport properties of ultra-small MOSFETs. 相似文献