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81.
82.
Hanne Løje Ditte Green‐Petersen Jette Nielsen Bo M Jørgensen Kristina N Jensen 《Journal of the science of food and agriculture》2007,87(2):212-217
Low‐field 1H nuclear magnetic resonance (NMR) tranverse relaxations were measured on intact and minced muscle from raw and smoked salmon differing in size (small or large) and storage days after smoking (1, 11 and 20 days). Water distribution in the samples was calculated from the NMR signals by the use of multi‐way data analysis. For intact and minced salmon samples, three water ‘pools’ with T2 values of 38, 50 and 182 ms and of 33, 50 and 183 ms, respectively, were identified. For both intact and minced samples, the size of water pool I and II were affected by storage time after smoking, whereas the size of pool III was affected by the size of the fish. Intact fillet samples taken near the skin and near the middle of the fillet differed with respect to shape of the NMR relaxation signal reflecting a non‐uniform distribution of the size of the three water pools in intact fillet. Copyright © 2006 Society of Chemical Industry 相似文献
83.
Jens Hetland Hanne Marie Kvamsdal Geir Haugen Fredrik Major Vemund Kårstad Göran Tjellander 《Applied Energy》2009
Sevan Marine and Siemens have developed a floating power plant – entitled Sevan GTW (gas-to-wire) – based on Sevan’s cylindrical platform and Siemens’ SCC-800 combined cycle, and SINTEF has adapted a post-combustion CO2 capture process for on board integration including compression and preconditioning of the CO2. Main emphasis has been placed on developing an optimised conceptual design within the structural constraints, and assessing how efficient the capture unit may be operated in consideration of the dynamic behaviour induced by the sea on the absorber and desorber columns via the floating carrier. The rational behind this technology selection is the urgency in making appropriate steps for a quick start for remote power generation at sea with the inclusion of CCS to serve offshore oil and gas operations. This calls for modular power blocks made up by high efficient combined power cycles with post-combustion exhaust gas cleaning. From this point of view a system with four absorption columns and one desorber unit has been determined based on structured packing material. The capture process has been integrated with the power cycle in due consideration of the sea forces. It is shown that a permanent tilt becomes more important than periodic movements provided the harmonic periods are kept within a certain level (<20 s). Operational conditions and constraints vis-à-vis movements and trimming of the floater have been addressed and discussed with reference to available literature. This also includes the liquid hold-up and gas–liquid interfacial area in the absorption columns linked with tilting. Optimisation reveals that a reboiler duty of 3.77 GJ/ton CO2 would result in the lowest capture cost. With a energy penalty of 9%-points the Sevan GTW concept presents itself as a realistic concept deemed to be within reach today. 相似文献
84.
Rhodes Gillian; Lie Hanne C.; Ewing Louise; Evangelista Emma; Tanaka James W. 《Canadian Metallurgical Quarterly》2010,36(1):217
Discrimination and recognition are often poorer for other-race than own-race faces. These other-race effects (OREs) have traditionally been attributed to reduced perceptual expertise, resulting from more limited experience, with other-race faces. However, recent findings suggest that sociocognitive factors, such as reduced motivation to individuate other-race faces, may also contribute. If the sociocognitive hypothesis is correct, then it should be possible to alter discrimination and memory performance for identical faces by altering their perceived race. We made identical ambiguous-race morphed faces look either Asian or Caucasian by presenting them in Caucasian or Asian face contexts, respectively. However, this perceived-race manipulation had no effect on either discrimination (Experiment 1) or memory (Experiment 2) for the ambiguous-race faces, despite the presence of the usual OREs in discrimination and recognition of unambiguous Asian and Caucasian faces in our participant population. These results provide no support for the sociocognitive hypothesis. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
85.
86.
Jerusalem artichoke tubers (Helianthus tuberosus L.) undergo enzymatic browning when peeled or cut, and turn grey after boiling, due to after-cooking darkening reactions between iron and phenolic acids. In an attempt to reveal the components responsible for these discolouration reactions, sensory evaluation and instrumental colour measurements were related to contents of total phenolics, phenolic acids, organic acids and iron in three varieties of raw and boiled Jerusalem artichoke tubers harvested in the autumn and the spring. No differences were found between varieties in sensory evaluated enzymatic browning, but Rema and Draga had higher scores than Mari in after-cooking darkening. Jerusalem artichoke tubers had higher contents of total phenolics, phenolic acids and citric acid in the autumn and low contents in the spring, while it was the opposite for malic acid. None of the chemical parameters investigated could explain the discolouration of the Jerusalem artichoke tubers. 相似文献
87.
Rural residents have different expectations concerning what the rural landscape should be like and what it should be used for. This is especially the case at the rural-urban interface, where the characteristics of rural and urban landscapes have become blurred. In this article, the concept of sense of place is used to explore the relationship between humans and landscape at the rural-urban fringe. Based on a quantitative survey data set, this article examines how the landscape perceptions of local residents can be understood from the basis of their sense of place in Nurmijärvi, a municipality located close to the Helsinki Metropolitan Area in southern Finland. A factor analysis revealed four clusters: Socially connected, Weak bonds, Roots and resources and Committed to place. The clusters differed by their socio-economic profiles as well as their sense of place. The Roots and resources cluster differed most of the other clusters, but in general the differences between the clusters in general landscape perceptions were relatively small. Although a strong sense of place is often assumed to lead to care of place, the willingness to contribute to the landscape did not differ significantly between the clusters. In addition the study revealed the existence of two different approaches to landscape in the rural-urban interface: landscape as a scenery and landscape as a dwelling place. 相似文献
88.
Hanne Falsig Juan Shen Tuhin Suvra Khan Wei Guo Glenn Jones Søren Dahl Thomas Bligaard 《Topics in Catalysis》2014,57(1-4):80-88
We present a study of the dissociative chemisorption of NO, O2, and N2 over close-packed, stepped, kinked, and open (fcc {111}, {211}, {311}, {532}, {100}, and {110}) transition metal facets using density functional theory (DFT). The offset of the Brønsted–Evans–Polanyi (BEP) relations suggest that the {111} surface is the least reactive, and that the {110} surface is the most reactive. This observation is verified by establishing volcano-relations based on mean-field microkinetic models for each facet, showing that the maximum rate over {110} is 4 orders of magnitude larger than the maximum {111} rate. The ordering of the maximum activity over the facets is: {110} > {100} ~ {532} > {311} ~ {211} > {111}, which is in general agreement with the offset in the BEP relations. We show that the top-point location and shape of the volcano relations are approximately independent of facet. This observation lends credibility to the approach of analyzing trends in catalytic reactivity over a single low-index facet, and assuming the experimentally observed activity trends are qualitatively well-described by such a single-facet analysis. Our study suggests that a key element for generally obtaining quantitative agreement between theory and experiments is for the simulations to address in detail the propensities of the various types of active sites. Finally, we show that the ordering of NO decomposition rates among metals and facets is essentially unaltered when using BEP- and scaling relations in the microkinetics instead of explicit DFT calculations for each elementary reaction step, and that using a “universal” BEP relation introduces no significant additional qualitative error in trend prediction. 相似文献
89.
Differential scanning calorimetry (DSC) is widely used to study the stability of amorphous solids, characterizing the kinetics of crystallization close to the glass-transition temperature T(g). We apply ultrafast DSC to the phase-change material Ge(2)Sb(2)Te(5) (GST) and show that if the range of heating rates is extended to more than 10(4) K s(-1), the analysis can cover a wider temperature range, up to the point where the crystal growth rate approaches its maximum. The growth rates that can be characterized are some four orders of magnitude higher than in conventional DSC, reaching values relevant for the application of GST as a data-storage medium. The kinetic coefficient for crystal growth has a strongly non-Arrhenius temperature dependence, revealing that supercooled liquid GST has a high fragility. Near T(g) there is evidence for decoupling of the crystal-growth kinetics from viscous flow, matching the behaviour for a fragile liquid suggested by studies on oxide and organic systems. 相似文献
90.
Rosenquist H Sommer HM Nielsen NL Christensen BB 《International journal of food microbiology》2006,108(2):226-232
To evaluate the effect of specific slaughter operations on the contamination of broiler carcasses with naturally occurring thermotolerant Campylobacter, experiments were carried out in two Danish commercial slaughter plants (Plant I and Plant II). Six broiler flocks determined Campylobacter positive prior to slaughter were investigated at four sampling locations within each slaughter plant. Quantification of thermotolerant Campylobacter in 30 neck skin samples per flock per sampling location showed that the evisceration operation in Plant I led to a significant increase in the Campylobacter concentration of 0.5 log(10) cfu/g in average, whereas no significant changes were observed during this operation in Plant II. Air chilling (Plant I) and water chilling (Plant II), both including a carcass wash prior to the chilling operation, caused similar, but significant reductions of 0.83 and 0.97 log(10) cfu/g, respectively. In packed frozen chickens (Plant II) an additional reduction of 1.38 log(10) cfu/g in average was obtained due to the freezing operation. In packed chilled chickens (Plant I), however, the number of thermotolerant Campylobacter per gram remained at the same level as after air chilling. Enumeration of thermotolerant Campylobacter in 30 intestinal samples per flock showed that in two of the six flocks examined the within flock colonization was very low (<3% and 27% positive samples). The remaining four flocks were colonized at percentages of 100 (three flocks) and 97 (one flock) and had intestinal mean counts ranging from 6.65 to 8.20 log(10) cfu/g. A correlation between Campylobacter concentrations in intestinal content and on chicken carcasses after the defeathering operation was documented. This finding indicates that a reduction in the Campylobacter concentration on chicken carcasses may also be obtained by interventions aimed at reducing the concentration of Campylobacter in the intestines of the living birds. 相似文献