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91.
In recent years interest in polyphenols as a nutrient in vegetables and fruits has increased because of polyphenols’ positive
effects on human health. The interest focuses on the sensory properties of polyphenols and their influence on the taste of
fruits and derived products. This article presents the development of a bioanalytical measurement technique enabling the determination
of the total polyphenol content (TPC) of fresh grapes within a few minutes. Furthermore this technique allows the control
of TPC during production processes, e. g. fermentation of wine. 相似文献
92.
Weiss ME Fischer DF Xin ZQ Jautze S Schweizer WB Peters R 《Angewandte Chemie (International ed. in English)》2006,45(34):5694-5698
93.
Tóth G Wieczorek W Gross D Krischek R Schwemmer C Weinfurter H 《Physical review letters》2010,105(25):250403
We present a scalable method for the tomography of large multiqubit quantum registers. It acquires information about the permutationally invariant part of the density operator, which is a good approximation to the true state in many relevant cases. Our method gives the best measurement strategy to minimize the experimental effort as well as the uncertainties of the reconstructed density matrix. We apply our method to the experimental tomography of a photonic four-qubit symmetric Dicke state. 相似文献
94.
Sascha Bachmann Matthias Reitzner 《Stochastic Processes and their Applications》2018,128(10):3327-3352
Concentration bounds for the probabilities and are proved, where is a median or the expectation of a subgraph count associated with a random geometric graph built over a Poisson process. The lower tail bounds have a Gaussian decay and the upper tail inequalities satisfy an optimality condition. A remarkable feature is that the underlying Poisson process can have a.s. infinitely many points.The estimates for subgraph counts follow from tail inequalities for more general local Poisson U-statistics. These bounds are proved using recent general concentration results for Poisson U-statistics and techniques involving the convex distance for Poisson processes. 相似文献
95.
Andreas Darmann Edith Elkind Sascha Kurz Jérôme Lang Joachim Schauer Gerhard Woeginger 《International Journal of Game Theory》2018,47(3):767-796
We consider a setting where one has to organize one or several group activities for a set of agents. Each agent will participate in at most one activity, and her preferences over activities depend on the number of participants in the activity. The goal is to assign agents to activities based on their preferences in a way that is socially optimal and/or stable. We put forward a general model for this setting, which is a natural generalization of anonymous hedonic games. We then focus on a special case of our model where agents’ preferences are binary, i.e., each agent classifies all pairs of the form ‘(activity, group size)’ into ones that are acceptable and ones that are not. We formulate several solution concepts for this scenario, and study them from the computational point of view, providing hardness results for the general case as well as efficient algorithms for settings where agents’ preferences satisfy certain natural constraints. 相似文献
96.
Florian J. Stadler Christian Piel Joachim Kaschta Sascha Rulhoff Walter Kaminsky Helmut Münstedt 《Rheologica Acta》2006,45(5):755-764
Linear high-density polyethylenes with molar masses M
w between 240 and 1,000,000 g/mol, obtained by metallocene catalysts, were characterized in shear using oscillatory and creep tests. The polydispersities of the molar mass distributions (MMDs) lay between 1 and 16. The resulting zero shear-rate viscosities η0 covered a range from 2.5×10−3 to around 108 Pas. Above a critical molar mass of M
c≈2,900 g/mol, the experimental results can be described by the relation η0 ∼ M
w3.6, independently of the MMD. The oscillatory data were fitted with a Carreau–Yasuda equation. The resulting parameters were correlated to molecular structure. The parameter a, being a quantity for the width of the transition between the Newtonian and the non-Newtonian regime, showed a dependence on the molar mass M
w but not on M
w/M
n. The parameter λ of the Carreau-Yasuda equation was found to be the reciprocal crossover frequency for all samples with a log-Gaussian MMD. λ depends on the molar mass M
w and also on M
w/M
n.
相似文献
Helmut MünstedtEmail: Phone: +49-9131-8527604Fax: +49-9131-8528321 |
97.
The parameters characterizing the absorption, fluorescence and phosphorescence of 10-dodecylisoalloxazine (DIA), 10-octadecylisoalloxazine (OIA) 3-methyl-10-dodecylisoalloxazine (MDIA) embedded into polymeric matrices (polystyrene – PS, polymethacrylate methyl – PMM and poly(vinyl alcohol) – PVA) were studied. It was found that both the polarity of microenvironment and its structure influenced the changes of the spectral properties of the examined amphiflavins. 相似文献
98.
We study open point sets in Euclidean spaces $\mathbb{R }^d$ R d without a pair of points an integral distance apart. By a result of Furstenberg, Katznelson, and Weiss such sets must be of Lebesgue upper density $0$ 0 . We are interested in how large such sets can be in $d$ d -dimensional volume. We determine the exact values for the maximum volumes of the sets in terms of the number of their connected components and dimension. Here techniques from diophantine approximation, algebra and the theory of convex bodies come into play. Our problem can be viewed as a counterpart to known problems on sets with pairwise rational or integral distances. It possibly opens a new research direction with strong links to topology and measure theory. 相似文献
99.
Gaertner S Bourennane M Kurtsiefer C Cabello A Weinfurter H 《Physical review letters》2008,100(7):070504
We introduce a new quantum protocol for solving detectable Byzantine agreement (also called detectable broadcast) between three parties, and also for solving the detectable liar detection problem. The protocol is suggested by the properties of a four-qubit entangled state, and the classical part of the protocol is simpler than that of previous proposals. In addition, we present an experimental implementation of the protocol using four-photon entanglement. 相似文献
100.
We demonstrate the generation of high-energy picosecond pulses directly from a thin-disk laser oscillator by employing a self-imaging active multipass geometry. Stable single-pulse operation has been obtained with an average output power in excess of 50 W, excluding a cw background of 8%, at a repetition rate of 3.8 MHz. Self-starting passive mode locking was accomplished using a semiconductor saturable absorber mirror. The maximum pulse energy was 13.4 microJ at a pulse duration of 1.36 ps with a time-bandwidth product of 0.34. Single-pass external frequency doubling with a conversion efficiency of 60% yielded >28 W of average power at 515 nm. 相似文献