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101.
102.
This paper investigates the characteristics of regions that contribute to their positioning within the emerging innovative
networks supported by the European Union’s Framework Program using a spatial-network approach. Although the importance of
research collaborations in network formation has been generally recognized, relatively little research has investigated why
some regions are able to attain prominent network positions, while others do not. We analyze a spatially detailed data base
of EU Framework Program-supported research ventures in Austria to understand how specific geographical nodes come to occupy
important positions within key research networks. The paper deploys what is termed here a network positioning function to
investigate the question of network centrality and at the same time to illustrate the possibilities of combining network and
spatial analysis to examine this or other research questions where similar approaches might be applicable. Findings reveal
the factors important for understanding advantageous positions enjoyed by regional districts as measured by alternative centrality
concepts. Concepts that distinguish innovation exploitation from exploration were used to interpret network positions, which
further clarify positioning in highly localized versus distant member networks. 相似文献
103.
Maya Berg Gunther Bal Dr. Annelies Goeminne Dr. Pieter Van der Veken Prof. Dr. Wim Versées Prof. Dr. Jan Steyaert Prof. Dr. Achiel Haemers Prof. Dr. Koen Augustyns Prof. Dr. 《ChemMedChem》2009,4(2):249-260
A series of bicyclic N ‐arylmethyl‐substituted iminoribitols were synthesised and evaluated in vitro against T. vivax nucleoside hydrolase. The importance of the N–Asp40 interaction was confirmed and depends on an optimal pKa value, which can be influenced by substituents. The compounds were active inhibitors of nucleoside hydrolase (IAG‐NH) and are inactive against human purine nucleoside phosphorylase.
104.
105.
106.
Gunther Hpfinger 《真空研究与实践》1999,11(3):145-149
Vacuum generation by product vapour driven jet pumps in the plastic fibre production For industrial application in the fiber industry product vapour driven jet pumps in combination with liquid ring pumps for generation of vacuum have proved and succeeded. The most important advantages of such vacuum systems are the high operational reliability, small wear and tear, customized design, low environmental impact, reasonable investment costs and simple operation. 相似文献
107.
Cordier C. Mechin L. Gunther C. Sing M.L.C. Bloyet D. Mosser V. 《IEEE sensors journal》2005,5(5):934-941
The response of a Hall-effect sensor to a spatially dependent magnetic field is of importance for many applications such as magnetic microscopy and nondestructive testing. Using the analytical expression of the response of a Greek cross Hall sensor response to an ideal field dot published a few years ago, we have calculated its sensitivity and its full width at half maximum for the field produced by a magnetic dipole and by two coplanar lines. The experimental results are in good agreement with theory. They show that the spatial resolution is roughly equal to the dimension of the central part of the Greek cross and that a flux-meter approximation is not appropriate for modeling such Hall-effect sensors for very close field sources. 相似文献
108.
Yan Shen Ushula Mengesha Tefashe Thomas Loewenstein Gunther Wittstock 《Electrochimica acta》2009,55(2):458-21212
The overall efficiency of the light-induced charge separation in dye-sensitized solar cells depends on the kinetic competition between back electron transfer and dye regeneration processes by a redox electrolyte. In a previous study, the reduction of the intermittently formed photo-oxidized dye molecules by iodide ions in the electrolyte phase was investigated using the feedback mode of a scanning electrochemical microscope (SECM) and a quantitative model had been derived. Here we provide a more thorough experimental verification of this model by variation of the excitation wavelength, light intensities and mediator concentrations. Nanoporous ZnO/Eosin Y films prepared by self-assembly were used as model electrodes and were used with an iodide/triiodide electrolyte. The experimentally found effective rate constants could be related to the rate constant for the reaction of the dissolved donor with photo-oxidized Eosin Y bound to ZnO and the absorption spectrum of the dye and confirmed the assumption made in the derivation of the model. For the regeneration process of Eosin Y, a rate constant of kox with different light emitting diodes and light intensities is determined. 相似文献
109.
Kai Magenheimer Gunther Reinhart Cornelius S. L. Schutte 《Production Engineering》2014,8(1-2):143-152
Because of the rising complexity of indirect business areas, processes become less transparent and it is therefore more difficult to distinguish between value-adding activities and waste. As an essential requirement for purposeful optimization, all existing types of waste in a process must be identified and quantified in terms of their negative impacts on the process productivity and the customer’s wishes. Hence, this article proposes an approach that increases the transparency and ensures objectivity by concentrating on the value stream, revealing weaknesses, detecting their causes, and evaluating the impact on the process according to the philosophy of Lean Management. The methodology is separated into three main steps: process modeling, analysis, and the evaluation of waste in indirect business areas. This results in an effect-orientated classification of potential waste in the process and yields a priority list of fields of action. The basis for the implementation of process optimization is thus developed. 相似文献
110.
Terpyridine-manganese complexes: A new class of bleach catalysts for detergent applications 总被引:1,自引:0,他引:1
Torsten?WieprechtEmail author Uwe?Heinz Juntao?Xia Gunther?Schlingloff Josef?Dannacher 《Journal of surfactants and detergents》2004,7(1):59-66
Oxidation catalysis is one approach used to improve the performance of hydrogen peroxide in laundry bleach applications. We
introduce herein a new class of bleach catalysts based on the ligand 2,2′∶6′,2″ terpyridine. A set of manganese complexes
of substituted terpyridines was investigated with respect to their physicochemical properties and bleach performance. Introduction
of electron-donating hydroxy and amine substituents in the 4-position of the individual pyridine rings improves the bleach
performance in model experiments with morin (2′,3,4′,5,7-pentahydroxyflavone) in solution as well as on tea-stained cotton
fabrics. All the catalysts show excellent bleach performance at 40 and 25°C under European washing conditions. Performance
is superior to that of the activator tetraacetyl ethylenediamine (TAED) but depends critically on the substitution pattern.
Dye damage caused by the catalysts is similar to that of TAED, proving that catalytic bleach systems with high performance
and low damage are indeed feasible. Model experiments revealed that the complexes are highly stable under aqueous alkaline
conditions in the presence of hydrogen peroxide. The optimal pH for catalytic activity is about 10. For a catalyst to have
a high bleach performance, it must possess a sufficiently low activity to catalyze disproportionation of hydrogen peroxide,
which is a major side reaction of catalytic bleach with manganese complexes. All the catalysts showed a similar affinity for
the cotton fabric, suggesting that differences in bleach activity of complexes are not caused by differences in the fabric
affinity. 相似文献