The impact of preparation: conditions for developing professional knowledge through simulations

2015 ◽  
Vol 67 (4) ◽  
pp. 529-542 ◽  
Author(s):  
David Sjöberg ◽  
Staffan Karp ◽  
Tor Söderström
Keyword(s):  
Professional Knowledge ◽  
Preparation Conditions ◽  
The Impact

scholarly journals Electrical Properties of Sr0.86Y0.08TiO3 Under Redox and Full Cell Fabrication Conditions

2012 ◽  
Vol 9 (5) ◽  
Author(s):  
Li Zhao ◽  
Jacob Brouwer
Keyword(s):  
Electrical Properties ◽  
Strong Dependence ◽  
Lattice Parameter ◽  
Reducing Atmosphere ◽  
Preparation Conditions ◽  
Oxidation Reduction ◽  
Reducing Conditions ◽  
Sofc Anode ◽  
Cell Fabrication ◽  
The Impact

The effects of manufacturing and preparation conditions on the structural and electrical properties of Sr0.86Y0.08TiO3 (SYT) reduced in 5% NH3 (95% N2) are discussed. The realization of an SYT-based SOFC anode is challenging because the conductivity of SYT is highly dependent upon the thermal history combined with heat treatment atmosphere used in manufacturing. To obtain highly conductive SYT as a candidate for an SOFC anode material, all samples in this study were prereduced to 1400 °C under reducing conditions (ammonia) for 8 h. After prereduction, three samples were oxidized in air at 850 °C, 950 °C, and 1050 °C, respectively, for 4 h to evaluate the impact of oxidizing conditions in practical cell fabrication processes on the SYT conductivity. XRD analyses showed that the lattice parameter of SYT sintered in ammonia was slightly different than the sample sintered in air. Measured at 800 °C in reducing atmosphere (dry N2/4% H2), the maximum electrical conductivity of 36.3 S/cm was observed in SYT reduced in ammonia at 1400 °C. However, the observed conductivities were not preserved after oxidation-reduction cycles. Various SYT samples prereduced in ammonia at 1400 °C and then oxidized in air at 850 °C, 950 °C, and 1050 °C showed an irreversible drop on conductivity measured in a reducing atmosphere, and the higher the oxidation temperature, the lower the conductivity became. The conductivity results indicate a strong dependence upon the SYT manufacturing and processing conditions. Despite the irreversible drop due to the oxidation cycle, the conductivity of SYT sintered in ammonia at 1400 °C is still reasonable as a candidate for SOFC anodes, with careful management of cell fabrication conditions to avoid any oxidation processes at temperatures above 1050 °C.

scholarly journals Effects of an Interdisciplinary Course on Pre-Service Primary Teachers’ Content Knowledge and Academic Self-Concepts in Science and Technology–A Quantitative Longitudinal Study

2021 ◽  
Vol 11 (11) ◽  
pp. 744
Author(s):  
Melanie Marita Beudels ◽  
Karsten Damerau ◽  
Angelika Preisfeld
Keyword(s):  
Content Knowledge ◽  
Science And Technology ◽  
Professional Knowledge ◽  
Primary Teachers ◽  
Field Of Study ◽  
Major Field ◽  
Course Format ◽  
Interdisciplinary Course ◽  
The Impact ◽  
Experimental Group

Primary school teachers need adequate professional knowledge and motivational orientations to qualify scientifically and technologically literate students. Previous studies have focused on the impact of coursework on (pre-service) primary teachers’ content knowledge, rather than on the development of academic self-concepts. In addition, the influence of the course format and the major field of study has not been investigated much to this date. Thus, this study examines the effects of an interdisciplinary course on pre-service primary teachers’ content knowledge and academic self-concepts in science and technology using a quasi-experimental, quantitative, pre-post-follow-up design (n = 202). Whilst no significant changes in knowledge were revealed for the baseline group not participating in the course, significant short-term and long-term cognitive gains were found for the experimental group. Biology-, chemistry-, physics- and technology-related self-concepts increased significantly when participating in the course. The results also indicate that the course format and major field of study can have an impact on the development of pre-service teachers’ professional knowledge. Regarding the development of academic self-concepts in the experimental group, it can be assumed that both the weekly and block course format are beneficial for heterogeneous learner groups consisting of pre-service teachers with different major fields of study.

scholarly journals Making multiplication meaningful: Teaching for conceptual understanding

2019 ◽  
Vol 19 (1) ◽  
pp. 17-25
Author(s):  
Judith Mills
Keyword(s):  
Conceptual Understanding ◽  
Word Problems ◽  
Research Study ◽  
Professional Knowledge ◽  
Related Word ◽  
Mathematical Concepts ◽  
Children’S Learning ◽  
Mathematics Knowledge ◽  
Teaching Of Mathematics ◽  
The Impact

  The term numeracy is used widely in schools today and brings with it the expectation that students will be taught both how to do the mathematics, alongside an understanding of the concepts associated with the procedural application. One issue, which has arisen with the terminology ‘numeracy classroom’, is how to best support teachers to enhance their teaching of mathematics to allow this understanding to occur. This article stems from a larger research study that analysed the professional knowledge of teachers when teaching numeracy, and the impact their mathematics knowledge and procedural application had on children’s learning. This article presents observations of three teachers teaching a multiplication lesson (the first in a series of lessons over a six-week period) as they developed their students’ understanding of the mathematical concepts associated with the interpretation of the multiplication symbol. An analysis of the findings shows when the teachers used manipulatives, related word problems to the children’s lives, and promoted discussion in groups, a greater understanding of multiplication was apparent.    

scholarly journals The impact of injector placement on the dose preparation conditions in a gasoline direct injection system

2018 ◽  
Vol 172 (1) ◽  
pp. 35-43
Author(s):  
Maciej SIDOROWICZ ◽  
Ireneusz PIELECHA
Keyword(s):  
Fuel Injection ◽  
Direct Injection ◽  
Angular Position ◽  
Combustion Process ◽  
Gasoline Direct Injection ◽  
Injection System ◽  
Secondary Importance ◽  
Preparation Conditions ◽  
Direct Fuel Injection ◽  
The Impact

Direct fuel injection requires appropriate conditions for proper ignition of the formed mixture. The proper combustion process is shaped by the direct fuel injection, whose parameters vary. Preparation of the dose requires proper injector placement in the combustion chamber. This article focuses on the issue of the injector specific spatial and angular position in order to implement the injection and atomization of the fuel. The injectors pseudo-optimal location has been presented along with several changed positions. The research was conducted as a simulation experiment using AVL FIRE 2017 software. The best position of the injector was selected based on the fuel spraying and injection process indicators. It has been shown that the spatial position has the most impact and the injector placement angle is of secondary importance.

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