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41.
Diana Carolina Guío-Pérez Tobias Pröll Hermann Hofbauer 《Chemical Engineering Research and Design》2014
The intensification of gas-solids contact in the fuel reactor of a chemical looping combustion system is enhanced with the installation of ring-type internals. This can be a key issue for achieving the necessary fuel conversion rates. Wedged rings, previously designed and tested, were found to increase the particle concentration in the counter current section of the fuel reactor and hence, to achieve a more homogeneous particles concentration along this zone. The present work investigates the effect of the mentioned internals on the residence time distribution of particles in the fuel reactor of a dual circulating fluidized bed system for chemical looping. The study was carried out in a cold flow model especially designed for the fluid-dynamic analysis of the system equipped with a recently developed residence time measurement device based on the detection of ferromagnetic tracer particles through inductance measurement. Ring internals proved the positive effect on the particles residence time, the residence time distribution is more symmetric and shows lower dispersion, the flow pattern is more plug-flow-like, these effects are intensified with the reduction of the aperture ratio of the rings. On the other hand, the upward particle transport in the counter-current zone of the fuel reactor also increases with the installation of the rings, increasing the bypass flow of solids through the fuel reactor's return loop (internal circulation). For high internal circulation rates the solids residence time distribution of the fuel reactor is dominated by the bypass effect. The findings may be used for focused design improvement of the investigated fluidized bed system. 相似文献
42.
Angel Medina Markus Schmidt-Heydt Diana L. Cárdenas-Chávez Roberto Parra Rolf Geisen Naresh Magan 《Journal of the Royal Society Interface》2013,10(85)
The objective of this study was to integrate data on the effect of water activity (aw; 0.995–0.93) and temperature (20–35°C) on activation of the biosynthetic FUM genes, growth and the mycotoxins fumonisin (FB1, FB2) by Fusarium verticillioides in vitro. The relative expression of nine biosynthetic cluster genes (FUM1, FUM7, FUM10, FUM11, FUM12, FUM13, FUM14, FUM16 and FUM19) in relation to the environmental factors was determined using a microarray analysis. The expression was related to growth and phenotypic FB1 and FB2 production. These data were used to develop a mixed-growth-associated product formation model and link this to a linear combination of the expression data for the nine genes. The model was then validated by examining datasets outside the model fitting conditions used (35°C). The relationship between the key gene (FUM1) and other genes in the cluster (FUM11, FUM13, FUM9, FUM14) were examined in relation to aw, temperature, FB1 and FB2 production by developing ternary diagrams of relative expression. This model is important in developing an integrated systems approach to develop prevention strategies to control fumonisin biosynthesis in staple food commodities and could also be used to predict the potential impact that climate change factors may have on toxin production. 相似文献
43.
The potential for community-led local sustainability initiatives to play a key role in a transition towards a low-carbon economy has been acknowledged by both policymakers and researchers. To date, such initiatives have predominantly been established through the efforts of volunteers, resulting in a scattered uptake across towns, cities and other communities in the UK and further afield. In a context where local and national Government are increasingly seeking to deliver local action on climate change in partnership with community organisations, is it possible or desirable for Government and other publicly funded bodies to successfully set up these grassroots initiatives “from the outside” where none exist already? This paper describes a project which explored this question through the provision of a 2-year programme of support for local action on climate change in a sub-region of the UK. Community development strategies were employed with a view to establishing new grassroots climate change initiatives in a range of different communities. The results indicate some potential for the strategy to meet with success, with several new groups and small-scale projects being established as a result. However, the short lifespan of many of the organisations set up and the relatively low impact on carbon emission reduction of their activities raises questions about the effectiveness of grassroots initiatives and how support of their activities can be delivered most effectively to maximise impact and improve cost effectiveness. 相似文献
44.
John McDonald Rosalee Wolfe Jerry Schnepp Julie Hochgesang Diana Gorman Jamrozik Marie Stumbo Larwan Berke Melissa Bialek Farah Thomas 《Universal Access in the Information Society》2016,15(4):551-566
Generating sentences from a library of signs implemented through a sparse set of key frames derived from the segmental structure of a phonetic model of ASL has the advantage of flexibility and efficiency, but lacks the lifelike detail of motion capture. These difficulties are compounded when faced with real-time generation and display. This paper describes a technique for automatically adding realism without the expense of manually animating the requisite detail. The new technique layers transparently over and modifies the primary motions dictated by the segmental model and does so with very little computational cost, enabling real-time production and display. The paper also discusses avatar optimizations that can lower the rendering overhead in real-time displays. 相似文献
45.
Diana Nanova Sebastian Beck Andreas Fuchs Tobias Glaser Christian Lennartz Wolfgang Kowalsky Annemarie Pucci Michael Kroeger 《Organic Electronics》2012,13(7):1237-1244
The degree of charge transfer in thin films of organic charge transfer (CT)-complexes, which are deposited via thermal evaporation, is examined via infrared-spectroscopy. We demonstrate a linear relationship between the shift in the excitation energy of the CN-stretching mode of CT-complexes with the acceptor 7,7,8,8-tetracyanoquinodimethane (TCNQ) and the charge transfer. The measured correlation corresponds very well with DFT calculations. For Na-TCNQ we observe a splitting in the peak of the CN-stretching mode, which can be explained by the coupling of two modes and was confirmed by the calculations. In CT-complexes with partial charge transfer the appearance of an electronic excitation is demonstrated. 相似文献
46.
47.
Production performance,meat composition and oxidative susceptibility in broiler chicken fed with different phenolic compounds 总被引:2,自引:0,他引:2
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48.
Julia Radwan-Pragłowska Marek Piątkowski Diana Kitala Łukasz Janus Agnieszka Klama-Baryła Wojciech Łabuś 《国际聚合物材料杂志》2019,68(7):351-359
In this work we present a novel strategy for chitosan-based scaffolds. Chitosan is a versatile biopolymer obtained from waste biomass known of its favorable biological properties. Thus it can replace other polymers in the preparation of bioactive scaffolds. To increase its durability chitosan can be crosslinked into form of the hydrogel yet application of toxic crosslinkers may lead to loss of biocompability. Mesenchymal stem cells can be used in cell therapy for advanced wound treatment. However their culture requires special biomaterials application. In this article a novel microwave-assisted synthesis method for bioactive chitosan scaffolds is presented. 相似文献
49.
Tijanić Ksenija Car-Pušić Diana Šperac Marija 《Neural computing & applications》2020,32(13):9343-9355
Neural Computing and Applications - Road construction projects on the territory of the Republic of Croatia are characterized by the overrun of planned costs. The experience of the contractor on... 相似文献
50.
Sergiu Cecoltan Izabela-Cristina Stancu Diana Maria Drăguşin Andrada Serafim Adriana Lungu Cătălin Ţucureanu Iuliana Caraş Vlad Constantin Tofan Aurora Sălăgeanu Eugeniu Vasile Romain Mallet Daniel Chappard Cristin Coman Mircea Istodorescu Horia Iovu 《Journal of materials science. Materials in medicine》2017,28(10):153