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21.
The chemical composition of the water-soluble extracts of mature Cheddar cheese were identified, with the emphasis on understanding the interplay of compounds contributing to the savoury taste in Cheddar. The ultra-filtered water-soluble extracts of two mature Cheddar cheeses were fractionated by gel permeation chromatography (GPC). By sensory evaluation, two taste-active GPC fractions were identified from each cheese. On the basis of chemical profiling of these fractions, aqueous model tastant mixtures were prepared and sensory omission tests carried out. Glutamic acid, organic acids and mineral salts were the main tastants, whereas the other amino acids had a limited impact on taste. The characteristic umami taste was explained by a synergistic effect of glutamic acid and salts. Matching umami taste intensities were obtained from different concentrations of glutamic acid and salts. Unmasking of a bitter or sweet taste from mixtures of sub-threshold concentrations of amino acids without glutamic acids was also observed. 相似文献
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Scientometrics - The Small Business Innovation Research (SBIR) program is the primary source of public funding in the United States for research by small firms on new technologies, and the National... 相似文献
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Emil Meng-Lund Jette Jacobsen Morten B. Andersen Mads L. Jespersen Jens-Jacob Karlsson Mats Garmer 《Drug development and industrial pharmacy》2014,40(5):604-610
The potential of buccal mucosa as a site for systemic absorption has attracted increased attention in recent years creating a need for new predictive in-vivo models. The aim of this study was to evaluate anaesthetised and conscious Göttingen mini-pigs as a model for buccal drug absorption by testing pH-dependent absorption of metoprolol from a solid dosage form. Buccal tablets buffered to pH 6.2 and pH 8.9, oral liquid and intravenous injection were tested in four conscious and anaesthetised Göttingen mini-pigs in a non-randomised cross-over study. Blood samples were collected and processed before analysis by ultra-performance liquid chromatography with tandem mass spectrometry detection. An ex-vivo flow retention model was applied to study release and retention of the bioadhesive buccal tablets. The Tmax obtained from the two buccal conscious groups (55?±?5 and 35?±?5?min) were significantly different to the buccal anaesthetised groups (120?±?0 and 165?±?15?min) for buccal tablet pH 6.2 and pH 8.9, respectively. Also, the absolute bioavailability from the anaesthetised buccal tablet pH 8.9 (20.7?±?4.0%) had a significant increase compared to all other buccal tablet groups. In conclusion, this study showed a pH-dependent absolute bioavailability of metoprolol when administrated as bioadhesive buccal tablets to anaesthetised mini-pigs. The anaesthesia was found to delay the time to reach maximal plasma concentration of metoprolol as compared to the conscious pig model when administrated as buccal tablets. 相似文献
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Morten D. Andersen 《Journal of the American Ceramic Society》2013,96(2):651-656
The incorporation of aluminum in the calcium–silicate–hydrate (C–S–H) phases formed by hydration of three different white Portland cements has been investigated by 29Si MAS NMR. The principal difference between the three cements is their bulk Al2O3 contents and quantities of alkali (Na+ and K+) ions. 29Si MAS NMR allows indirect detection of tetrahedral Al incorporated in the silicate chains of the C–S–H structure by the resonance from Q2(1Al) sites. Analysis of the relative 29Si NMR intensities for this site, following the hydration for the three cements from 0.5 d to 30 weeks, clearly reveals that the alkali ions promote the incorporation of Al in the bridging sites of the dreierketten structure of SiO4 tetrahedra in the C–S–H phase. The increased incorporation of Al in the C–S–H phase with increasing alkali content in the anhydrous cement is in accord with a proposed substitution mechanism where the charge deficit, obtained by the replacement of Si4+ by Al3+ ions in the bridging sites, is balanced by adsorption/binding of alkali ions in the interlayer region most likely in the near vicinity of the AlO4 tetrahedra. This result is further supported by similar 29Si MAS NMR experiments performed for the white Portland cements hydrated in 0.30M NaOH and NaAlO2 solutions. 相似文献
25.
Conditions for aggregation of CHP plants in the UK electricity market and exploration of plant size 总被引:1,自引:0,他引:1
Combined heat and power (CHP) plants with thermal stores may be suitable for sustainable energy production and the accommodation of fluctuating renewable energy sources. At the moment, in the UK, only a few CHP plants have thermal stores. Previous research has shown that thermal stores can improve the economics of CHP plants in the UK under the current market conditions. However, currently, it is only beneficial for CHP plants to sell their electricity to a third party, a Licensed Electricity Supplier, rather than to sell it directly to the power exchange market at prices which are much higher. If CHP plants aggregate, direct access to the power exchange market can become economically viable hence there is the possibility that thermal stores could further improve the economics of CHP plants under an aggregated electricity dispatch. This work firstly explains the conditions under which such plants could aggregate and act as a large power plant in the UK market, and secondly explores the most economic-size of gas engine and thermal store, in the case of aggregation, using energyPRO software and Excel spreadsheets. The work suggests that direct access to the power exchange market can improve the economics of the CHP plants. The highest Net Present Value (NPV), without heat dissipation, for a CHP plant exporting its electricity to the grid for a community heating load of 20 GW h, is more than £5 m, and is obtained for a 6 MW engine with a 28.2 MW h (900 m3) thermal store. The research suggests that such high electricity prices could make even larger plants more profitable than that; however, this can happen only if some of the produced heat is dissipated. 相似文献
26.
Daniel Andersen 《今日电子》2011,(4):49-52
低压交流照明系统
在过去的30年中,低压交流照明设备已日趋普及。如今,从室内局部照明到一般性的活动式投射灯照明,再到如花园和景观等户外应用照明中,此类照明系统随处可见。像宜家家居和美国家得宝这样的家居零售卖场和住宅美化商场极大推进了该技术在消费人群中的使用。这类低压照明系统采用特殊低压编码规则,终端用户可自行安装而无需外部承包商。因此,这些系统相对便宜且易于安装。 相似文献
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Monica H Carlsen Inger TL Lillegaard Anette Karlsen Rune Blomhoff Christian A Drevon Lene F Andersen 《Nutrition journal》2010,9(1):37