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921.
In this study, we used a simple impregnation method to prepare Fe–Ce–O x catalysts and tested them regarding their low-temperature (200–300 °C) selective catalytic reduction (SCR) of NO using NH3. We investigated the effects of Fe/Ce molar ratio, the gas hourly space velocity (GHSV), the stability and SO2/H2O resistance of the catalysts. The results showed that the FeCe(1:6)O x (Ce/Fe molar ratio is 1:6) catalyst, which has some ordered parallel channels, exhibited good SCR performance. The FeCe(1:6)O x catalyst had the highest NO conversion with an activity of 94–99% at temperatures between 200 and 300 °C at a space velocity of 28,800 h?1. The NO conversion for the FeCe(1:6)O x catalyst also reached 80–98% between 200 and 300 °C at a space velocity of 204,000 h?1. In addition, the FeCe(1:6)O x catalyst demonstrated good stability in a 10-h SCR reaction at 200–300 °C. Even in the presence of SO2 and H2O, the FeCe(1:6)O x catalyst exhibited good SCR performance. 相似文献
922.
AbstractPsychologists and mathematics educators have long viewed flexibility as critical to students’ mathematical development. In this paper, we focused on the multidimensional nature of flexibility to better understand how preference, knowledge, and use of effective methods for solving algebra problems are related. In Study 1, we identified research-based aspects of flexibility with algebra and assessed students on them following a two-step equations unit. Results indicated that certain aspects of flexibility develop prior to others and that prior knowledge of algebra plays a significant role in that development. Study 2 confirmed and elaborated on these results using a larger sample size. Implications for theory and for supporting flexibility in classrooms are discussed. 相似文献
923.
The term noise is used to describe fluctuations about the mean deterministic stationary value of a physical quantity. It is
now being increasingly realised that noise is an important ingredient to bring order in dynamical processes. Though it appears
counterintuitive, noise seems to help in directing transport processes in biological systems at the molecular level. In Part
2 of the article, we discuss some more examples of noise assisted directed motion. 相似文献
924.
925.
Phenol degradation in photochemically enhanced Fenton process was investigated in this work. UV-VIS spectra of phenol degradation showed the difference between photo-Fenton process and UV/H2O2, which is a typical hydroxyl radical process. A possible pathway diagram for phenol degradation in photo-Fenton process was proposed, and a mathematical model for chemical oxygen demand (COD) removal was developed. Operating parameters such as dosage of H2O2 and ferrous ions, pH, suitable carrier gas were found to impact the removal of COD significantly. The results and analysis of kinetic parameters calculated from the kinetic model showed that complex degradation of phenol was the main pathway for removal of COD; while hydroxyl radicals acted weakly in the photo-Fenton degradation of phenol. 相似文献
926.
927.
Meredith Mountford 《Innovative Higher Education》2005,30(3):213-227
This article describes strategies for redesigning the University of Missouri's Statewide Cooperative Ed.D. Cohort Program
in educational leadership. Results had suggested a need to redesign aspects of the program in order to achieve higher levels
of cognitive learning outcomes inclusive of transformational learning. To help meet this objective, the areas targeted for
redesign were the curriculum as it relates to issues of diversity and ethics, instruction as it relates to group dynamics
and cohort models, and increased time and a forum for students to reflect on their leadership practices. This forum also allowed
faculty to monitor and assess the transformational learning outcomes of their students. This article is meant to assist others
who are interested in fostering higher levels of transformational learning outcomes within their programs.
Meredith L. Mountford holds a Bachelor of Science degree from Illinois State University, a Master of Science degree in educational
administration from Northern Illinois University and a Philosophy of Science degree in educational administration from the
University of Wisconsin—Madison. She is an Assistant Professor and has served as Director for the Statewide Cooperative Ed.D.
Cohort Program in educational leadership at the University of Missouri—Columbia. 相似文献
928.
D. R. E. Cotton J. Winter W. Miller L. Dalla Valle 《Environmental Education Research》2018,24(11):1611-1626
AbstractUniversity rankings are increasingly important internationally, and in the UK include a sustainability ‘Green League’. However, there is little evidence about experiences of studying in ‘sustainable universities’. We report an empirical study at five universities in varied positions in the Green League, exploring students’ energy literacy, environmental attitudes and perceptions of their institution’s energy-saving efforts. Although the link to energy literacy is not clear, findings suggest that there are significant differences between students’ environmental attitudes at universities placed at different points in the league. In addition, students at higher ranked universities are more positive about their university’s energy-saving efforts, suggesting that these institutions may exhibit more overt manifestations of sustainability. This is important since students report being more likely to choose energy-conservation behaviours if there is visible representation of energy use. The study is the first to attempt a comparison between universities at different positions in a sustainability ranking. 相似文献
929.
930.
This study examined parent reports of behavioral and family functioning for 59 boys with learning disabilities (LD) and 65 nondisabled boys (NLD) of ages 6 to 12 years. Parents completed the Child Behavior Checklist (CBCL) and the Family Adaptability and Cohesion Evaluation Scale (FACES III). Boys with LD were reported as having significantly more behavior problems of both the Internalizing and Externalizing types than NLD boys. Individual scales yielded group differences indicating higher scores (more problems) for the group with LD on the Hyperactive, Schizoid or Anxious, Depressed, and Obsessive Compulsive scales, but no differences on the Aggressive or Social Withdrawal scales. Furthermore, families of boys with LD tended to score more frequently in the extreme (disturbed) range of family functioning. However, boys of families in the extreme range did not have more behavior problems than the boys of other families. The findings suggest that a greater than average proportion of boys with LD are at risk for developing psychological adjustment problems. 相似文献