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141.
An Adams Zanda Kruma Roland Verhé Norbert De Kimpe Viesturs Kreicbergs 《Journal of the American Oil Chemists' Society》2011,88(2):201-212
The flavoring of oils with herbs gives a specific taste and aroma to the oils and may increase their antimicrobial and antioxidant activity. The volatile aroma compounds in flavored rapeseed oil were studied as a function of flavoring conditions, by means of headspace solid-phase microextraction (SPME) followed by gas chromatography-mass spectrometry (GC-MS) analysis. Rapeseed oils were flavored with dried basil, oregano, and thyme at two different concentrations (3 and 6%) and were heated at different temperatures and for various time intervals, followed by filtration. In the headspace of flavored oils, the main volatiles of the dried herbs were detected. In general, the share of monoterpenes in the headspace of flavored oil was higher than in the original dried herbs, while sesquiterpenes and phenolic compounds were detected to a considerably lower extent in the oil than in the herbs. The concentrations of the volatiles detected in the oil increased with increasing heating time and temperature. 相似文献
142.
Krisztina Frey Viacheslav Iablokov Gérôme Melaet László Guczi Norbert Kruse 《Catalysis Letters》2008,124(1-2):74-79
Ag/TiO2 catalysts with different Ag loadings (2, 4, 7 and 10% (w/w)) have been prepared by means of co-precipitation of Ag- and TiO-oxalates followed by temperature programmed oxidation (TPO). The catalysts were subjected to CO oxidation in a flow reactor at atmospheric pressure and temperatures up to 573 K. Best conversion performance was obtained in a CO/O2 = 1:1 mixture over 10% Ag/TiO2 for which the temperature of 50% CO conversion was T 50 = 333 K. The initial reaction rates were determined in a circulation reactor at low conversions and apparent activation energies between 13 and 25 kJ/mol were found for all catalysts. Transmission electron microscopy shows a broad range of nano-sized Ag particles on TiO2 (nearly pure anatase). 相似文献
143.
Morteza Ganjaee Sari Norbert Stribeck Siamak Moradian Ahmad Zeinolebadi Saeed Bastani Stephan Botta Ehsan Bakhshandeh 《Polymer International》2014,63(2):195-205
Polypropylene (PP) was modified utilizing two types of polyesteramide‐based hyperbranched polymers (amphiphilic PS and hydrophilic PH). A maleicanhydride‐modified PP (PM) was used as a reactive dispersing agent to enhance the modification by grafting the hyperbranched polymers onto the PP chains. Pure PP, two different non‐reactively modified samples, i.e. excluding PM, and two different reactively modified samples, i.e. including PM, were studied. Investigating the morphology of the samples was performed by scanning electron microscopy. To follow the effect of the modification on the dynamic mechanical properties, dynamic mechanical analysis experiments both in the melt (rheometric mechanical spectrometry) and in solid state (dynamic mechanical thermal analysis) were carried out. In the next step, the nanocrystalline structure of the samples was studied by small angle X‐ray scattering (SAXS) in two different modes, i.e. static and recrystallization. Hundreds of SAXS patterns were analyzed automatically using procedures written in PV‐WAVE image‐processing software. The chord distribution function (CDF) was calculated and the long period (lp) of the crystal lamellae was extracted from the CDFs. The rheometric mechanical spectrometry results show that both hyperbranched polymers decrease complex viscosity η* and enhance liquid‐like behavior. This happens more significantly when PM is included. The dynamic mechanical thermal analysis results reveal that Tg decreases when PS and PH are added. In the reactively modified samples this reduction is compensated most probably because of the crosslinked structure formed through the grafting reaction between the hyperbranched polymers and PM. Such structure is confirmed by SAXS data and calculated CDFs in the recrystallization mode. Static SAXS data also show enhancement in the crosshatched morphology of the crystalline lamellae of PP for reactively modified samples compared with non‐reactively modified samples. © 2013 Society of Chemical Industry 相似文献
144.
Norbert Kubilus 《信息方略》2011,(9):7-7
CIO INSIGHT的内容可以非常丰富,我经常阅读,我觉得杂志还应该站在行业的角度给企业一些更宏观的建议,这样才能发挥更大的作用。——中国疾控中心信息中心主任 马家奇 相似文献
145.
There are many knowledge-based data mining frameworks and it is common to think that new ones cannot come up with anything new. This article refutes such claims. We propose a sophisticated unification mechanism and two-tier machine cache system aimed at saving time and memory. No machine is run twice. Instead, machines are reused wherever they are repeatedly requested (regardless of request context). We also present an exceptional task spooler. Its unique design facilitates efficient automated management of large numbers of tasks with natural adjustment to available computational resources. Dedicated task scheduler cooperates with machine unification mechanism to save time and space. The solutions are possible thanks to very general and universal design of machine, configuration, machine context, unique machine life cycle, machine information exchange, configuration templates and other necessary concepts. Results gained by machines are stored in a uniform way, facilitating easy results exploration and collection by means of a special query system and versatile analysis with series transformations. No knowledge about internals of particular machines is necessary to extensively explore the results. The ideas presented here, have been implemented and verified inside Intemi framework for data mining and meta-learning tasks. They are general engine-level mechanisms that may be fruitful in all aspects of data analysis, all applications of knowledge-based data mining, computational intelligence, machine learning or neural networks methods. 相似文献
146.
Dagmar Bruß Norbert Lütkenhaus 《Applicable Algebra in Engineering, Communication and Computing》2000,10(4-5):383-399
We review the main protocols for key distribution based on principles of quantum mechanics, describing the general underlying
ideas, discussing implementation requirements and pointing out directions of current experiments. The issue of security is
addressed both from a principal and real-life point of view.
Received: October 15, 1998; revised version: June 8, 1999 相似文献
147.
148.
Ahmed Amine Rekik Florence Azaïs Norbert Dumas Frédérick Mailly Pascal Nouet 《Journal of Electronic Testing》2011,27(3):411-423
This paper presents a behavioral model that can be used to improve the manufacturability of systems based on MEMS convective
sensors. This model permits to handle faults related to process scattering, taking into account not only the electrical and
lateral geometrical parameters but also the influence of the cavity depth. Moreover correlations between conductive and convective
phenomena are included. The model is validated with respect to FEM simulations and a very good agreement is obtained between
the behavioral model and FEM results. The proposed model can then be used in system-level simulations, for instance to evaluate
the impact of process scattering on the performances of the sensing part and/or to investigate different design and calibration
strategies with respect to the system robustness. 相似文献
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