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Kinetic knowledge is of great importance in achieving good control of the pyrolysis and gasification process and optimising
system design. An overall kinetic pyrolysis scheme is therefore addressed here. The kinetic modelling incorporates the following
basic steps: the degradation of the virgin biomass materials into primary products (tar, gas and semi-char), the decomposition
of primary tar into secondary products and the continuous interaction between primary gas and char. The last step is disregarded
completely by models in the literature. Analysis and comparison of predicted results from different kinetic schemes and experimental
data on our fixed bed pyrolyser yielded very positive evidence to support our kinetic scheme.
Project (No. 2001CB409600) Supported by the National Key Basic Research Program (973) of China 相似文献
93.
普通话二字组词语不同的声调组合方式 ,使前后位声调产生不同的动态变化形式。前位声调的动态变化明显表现在上声调变为低降调和中升调上 ;后位声调的动态变化则表现在调值的明显改变上。后位声调的动态变化更为普遍 ,应该引起足够的重视 相似文献
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Luce C. A. Claessens Jan van Tartwijk Anna C. van der Want Helena J. M. Pennings Nico Verloop Perry J. den Brok 《The Journal of educational research》2017,110(5):478-493
The authors voice teachers' perceptions of their interpersonal experiences with students in both positive and problematic relationships. Interview data from 28 teachers were examined by coding utterances on teacher and student interactions. Results indicate that teachers defined the quality of the relationship mostly by the level of communion (friendly vs. hostile), instead of by the level of agency (in control vs. powerless). Analyses of mentioned teacher and student behavior show a friendly interactional pattern for positive relationships and a hostile pattern for problematic ones. In teachers' perceptions, positive and problematic relationships also differed in context where encounters take place and topic of talk. Contrary to interactions in problematic relationships, encounters in positive relationships were mostly situated outside the classroom context and conversations during these encounters covered a wide range of topics. Implications for teacher education programs are discussed. 相似文献
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This is Part 2 of a two-part study of how APOS theory may be used to provide cognitive explanations of how students and mathematicians
might think about the concept of infinity. We discuss infinite processes, describe how the mental mechanisms of interiorization
and encapsulation can be used to conceive of an infinite process as a completed totality, explain the relationship between
infinite processes and the objects that may result from them, and apply our analyses to certain mathematical issues related
to infinity. 相似文献
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With the flooding of pornographic information on the Internet, how to keep people away from that offensive information is becoming one of the most important research areas in network information security. Some applications which can block or filter such information are used. Approaches in those systems can be roughly classified into two kinds:metadata based and content based. With the development of distributed technologies, content based filtering technologies will play a more and more important role in filtering systems. Keyword matching is a content based method used widely in harmful text filtering. Experiments to evaluate the recall and precision of the method showed that the precision of the method is not satisfactory, though the recall of the method is rather high. According to the results, a new pornographic text filtering model based on reconfirming is put forward. Experiments showed that the model is practical, has less loss of recall than the single keyword matching method, and has higher precision. 相似文献
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