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81.
SPHERES is a third-generation neutron backscattering spectrometer, located at the 20 MW German neutron source FRM II and operated by the Ju?lich Centre for Neutron Science. It offers an energy resolution (fwhm) better than 0.65 μeV, a dynamic range of ±?31 μeV, and a signal-to-noise ratio of up to 1750:1.  相似文献   
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In this study, drying of red-fleshed dragon fruit at different temperatures (40, 50, 60, 70 and 80 °C) and air velocities (1.0 and 1.5 m s−1) was conducted under the specific humidity of 25 g H2O kg−1 dry air. The results showed that drying at higher temperatures resulted in shorter drying times. However, temperature and air velocity did not significantly affect the total betacyanin contents and antioxidant capacities in dried products. Seven betacyanins identified by LC-MS were betanin, isobetanin, phyllocactin, isophyllocactin, betanidin 5 –O-(6′O-3-hydroxybutyryl)-β-glucoside, isobetanidin 5 –O-(6′O-3-hydroxybutyryl)-β-glucoside and decarboxylated phyllocactin. In addition, the temperature increased the isomerisation of betacyanins. The most preferable condition for preserving the colour and betacyanin contents of red-fleshed dragon fruit was the drying at a temperature of 80 °C and air velocity of 1.5 m s−1 since it could shorten the drying time and give a bright red colour to the dried product as well as it had no significant impact on the betacyanins.  相似文献   
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Recent studies have shown the involvement of GluN2A subunit-containing NMDA receptors in various neurological and pathological disorders. In the X-ray crystal structure, TCN-201 ( 1 ) and analogous pyrazine derivatives 2 and 3 adopt a U-shape (hairpin) conformation within the binding site formed by the ligand binding domains of the GluN1 and GluN2A subunits. In order to mimic the resulting π/π-interactions of two aromatic rings in the binding site, a [2.2]paracyclophane system was designed to lock these aromatic rings in a parallel orientation. Acylation of [2.2]paracyclophane ( 5 ) with oxalyl chloride and chloroacetyl chloride and subsequent transformations led to the oxalamide 7 , triazole 10 and benzamides 12 . The GluN2A inhibitory activities of the paracyclophane derivatives were tested with two-electrode voltage clamp electrophysiology using Xenopus laevis oocytes expressing selectively functional NMDA receptors with GluN2A subunit. The o-iodobenzamide 12 b with the highest similarity to TCN-201 showed the highest GuN2A inhibitory activity of this series of compounds. At a concentration of 10 μM, 12 b reached 36 % of the inhibitory activity of TCN-201 ( 1 ). This result indicates that the [2.2]paracyclophane system is well accepted by the TCN-201 binding site.  相似文献   
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The influence of graphitization and composition of carbide‐derived carbon (CDC) monoliths on the electrical and thermal conductivity was investigated. Carbon monoliths with varying porosities were synthesized employing biomorphous macroporous TiC and SiC as precursors. Graphitization was carried out in situ during high‐temperature chlorination with and without addition of nickel, iron, and cobalt chloride to the carbide. The graphitized monoliths showed improved properties. The results demonstrate that despite graphitic carbon also glass‐like carbon, stemming from the carbide synthesis, increases the thermal and electrical conductivity significantly.  相似文献   
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In lightweight walls and floors, the load‐bearing timber members are protected by cladding on the sides to form a divider between two fire compartments or to provide appropriate fire protection to the load‐bearing members. The spaces between the timber members can be void or filled with insulation materials. Although a huge number of different insulation materials exist, the most commonly used material is mineral wool insulation. The existing design model for glass wool‐insulated timber‐frame constructions, given in European standard 1995‐1‐2, assumes collapse of the glass wool after failure of the cladding. However, a new form of glass wool insulation, suitable for use at high maximum service temperatures, is now available in the market. The charring phase after the cladding's failure is known as the post‐protection phase. The behaviour of the new heat‐resistant glass wool in the post‐protection phase is similar to that of stone wool and considerably better than that of traditional glass wool. The protective properties of stone wool have changed over the last decades. Charring is one of the main parameters needed to calculate the resistance of a structure to fire. Based on experimental investigations, this paper describes the analysis of the effect of the insulation with regard to its ability to protect timber members against charring during the post‐protection phase. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
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Maps should be designed so that users can comprehend and use the information. Display decisions, such as choosing the scale at which an area is shown, depend on properties of the displayed information such as the perceived density (PD) of the information. Taking a psychophysical approach we suggest that the PD of information in a road map is related to the scale and properties of the mapped area. 54 participants rated the PD of 60 maps from different regions. We provide a simple model that predicts the PD of electronic road map displays, using the logarithm of the number of roads, the logarithm of the number of junctions and the length of the shown roads. The PD model was cross-validated using a different set of 60 maps (n = 44). The model can be used for automatically adjusting display scales and for evaluating map designs, considering the required PD to perform a map-related task.  相似文献   
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