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1.
Catalysis Letters - In the present paper, an efficient Cu-catalyzed regioselective acylation of indoles with phenylglyoxals was developed which is the first example of indolyl diketones synthesis...  相似文献   
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This paper represents an assessment of the main ageing phenomena in electrical double-layer capacitors (EDLCs). In this study the cycle life of the EDLC cells with a rated capacitance of 1,600 F has been investigated at different ambient temperatures and current rates. From the experimental results we can observe that the impact of the high ambient temperature is significant on the cycle life of the cells. Moreover, the results also show the negative impact of the current rate. The internal resistance tests showed that the increase of the resistance is much higher than the decrease of the capacitance. Thus, the ageing of the EDLC during cycling was clearly non-linear. Further the EIS measurements indicated the higher increase of the imaginary part of the impedance at low frequencies during cycling, which indicates the capacitance fade.  相似文献   
3.
采用场发射扫描电子显微镜(FE-SEM),研究转速对厚度为5 mm的6061-T6铝合金搅拌摩擦搭接焊接头的宏观和微观组织、硬度、搭接头剪切性能和失效模式的影响。结果表明:在最低的转速度下,上模板和下模板具有十分相似的硬度分布。采用EDX分析发现,焊核区的断裂面中含有Fe的化合物。  相似文献   
4.
The fatty acid and triacylglycerol composition of pili nut (Canarium ovatum) oil and fractions were analyzed by gas chromatography and reversed-phase high-performance liquid chromatography, respectively. The oil obtained by solvent extraction was low in polyunsaturated fatty acids and high in saturates. The polyunsaturated fatty acid (18∶2 and 18∶3) contents were less than 11%, whereas palmitic (16∶0) and stearic acid (18∶0) were 33.3 and 10.9%, respectively. The saturated fatty acid level of the low-melting fraction oil was reduced from 44.4 to 35.5% and the total unsaturated fatty acid levels were increased from 55.6 to 65% by fractional crystallization. Triacylglycerol analysis showed that the high-melting fraction (HM) from pili nut oil consisted of POP, POS, and SOS+SSO (P=palmitic acid, O=oleic acid, and S=stearic acid) in the proportion of 48.6, 38.8, and 8.7%, respectively. The physicochemical properties of the HM fraction were studied using differential scanning calorimetry and pulsed nuclear magnetic resonance. The results showed that the melting range and solid fat content of the HM fraction were very similar to those isolated from cocoa butter and olive oil. The content of POP played an important role in determining the melting range of the HM fraction. It is suggested that this HM fraction may have applications as a cocoa butter substitute in confectionery products.  相似文献   
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A novel, efficient, and very mild one-pot synthesis of methyl 2-[(Z)-4-aryl-5-morpholino-3-oxo-2,3-dihydrothiophen-2-ylidene]acetate derivatives under kinetic control has been developed. The title compounds were prepared by the reaction of thioacetomorpholides with dimethyl acetylene-dicarboxylate (DMAD) in the presence of K2CO3 in a non-polar solvent with excellent yields.  相似文献   
6.
BACKGROUND: The effects of modified waxy maize starch (MWMS, 10–32.5 g kg?1) as a replacement for varying levels of oil or both oil and wheat flour (WF) on the chemical and technological characteristics of 60% beef sausages were investigated. RESULTS: Addition of MWMS increased water‐holding capacity and decreased moisture content and both cooking and purge losses. Incorporation of MWMS improved organoleptic acceptance compared with control sausages. CONCLUSION: Sausage formula 5 (F5), containing 20 g kg?1 MWMS and 50 g kg?1 WF, was better (P < 0.05) than all other formulae. The total caloric content of the sausages decreased significantly with decreasing fat level (P < 0.05); for example, the decrease in fat content of 57.4% in F5 led to a significant decrease in energy value of 34.9% (P < 0.05). Copyright © 2011 Society of Chemical Industry  相似文献   
7.
In order to study the interaction of sloshing and structural vibrations of baffled tanks, a reduced order model based on modal analysis of structure model and boundary element method for fluids motion is developed. For this purpose, the governing equations of elastic structure and incompressible flow are used to derive simple models to simulate both fields. Using the modal analysis technique, the structural motions are applied to the fluid model and on the other hand by using boundary element method, the fluid loads are applied to the structural model. Based on this formulation, a code is developed which is applicable to an arbitrary elastic tank with arbitrary arrangement of baffles. The obtained results are validated with literature data and then the effects of baffle flexibility on the sloshing frequencies and structural vibration frequencies are investigated. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
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Earthquakes are a common occurrence in west Tennessee. Yet it is difficult to recognize related faults within the alluvial valley because of the unconsolidated sediments. Therefore, a synergetic approach to the analysis of lineament patterns was applied through the use of Landsat satellite and gravity anomaly data. Landsat satellite images were evaluated for lineament identification using different spectral bands, seasons, enhancement, and image interpretation techniques. Gravity trends were delineated on the gravity anomaly map of west Tennessee, and gravity lineaments were identified and mapped. The Landsat and gravity lineaments were quantitatively analyzed and compared by means of two‐dimensional histograms and rose diagrams. The results indicated that the primary direction of both Landsat and gravity lineaments was NE; N36‐63E for Landsat and N27‐72E for gravity. Weaker trends were found in N50‐55W for Landsat and N60‐70W for gravity. The NE trend of the lineaments corresponded to faults and was in accordance with reactivation of the Reelfoot rift near the Mississippi River. These results suggest that deeper features, maybe at the earthquake focal depth, probably extend to the land surface as Landsat detectable lineaments.  相似文献   
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