Evaluation of strontium-site-deficient Sr2Fe1.4Co0.1Mo0.5O6-δ-based perovskite oxides as intermediate temperature solid oxide fuel cell cathodes

In this paper strontium-site-deficient Sr₂Fe_1.4Co_0.1Mo_0.5O_6-δ-based perovskite oxides (S_xFCM) were prepared and evaluated as the cathode materials for intermediate temperature solid oxide fuel cells (IT-SOFCs). All samples exhibited a cubic phase structure and the lattice shrinked with increasing the Sr-deficiency as shown in XRD patterns. XPS results determined that the transition elements (Co/Fe/Mo) in S_xFCM oxides were in a mixed valence state, demonstrating the small polaron hopping conductivity mechanism existed. Among the samples, S_1.950FCM presented the lowest coefficient of thermal expansion of 15.62 × 10^-6 K^-1, the highest conductivity value of 28 S cm^-1 at 500 °C, and the lowest interfacial polarization resistance of 0.093 Ω cm² at 800 °C, respectively. Furthermore, an anode-supported single cell with a S_1.950FCM cathode was prepared, demonstrating a maximum power density of 1.16 W cm^-2 at 800 °C by using wet H₂ (3% H₂O) as the fuel and ambient air as the oxidant. These results indicate that the introduction of Sr-deficiency can dramatically improve the electrochemical performance of Sr₂Fe_1.4Co_0.1Mo_0.5O_6-δ, showing great promise as a novel cathode candidate material for IT-SOFCs.

Episodic Future Thinking in 4-Year-Olds, Poster Symposium: The who, what, where and when of episodic foresight development

The ability to project oneself into the future to pre-experience an event is referred to as episodic future thinking (Atance & O’Neill, 2001). Only a relatively small number of studies have attempted to measure this ability in pre-school aged children (Atance & Meltzoff, 2005; Busby & Suddendorf, 2005ab, 2010; Russell, Alexis, & Clayton, 2010).Perhaps the most successful method is that used by Russell et al (2010). In this task, 3- to 5-year-olds played a game of blow football on one end of a table. After this children were asked to select tools that would enable them to play the same game tomorrow from the opposite, unreachable, side of the table. Results indicated that only 5-year-olds were capable of selecting the right objects for future use more often than would be expected by chance. Above-chance performance was observed in this older group even though most children failed the task because there was a low probability of selecting the correct 2 objects from a choice of 6 by chance.This study aimed to identify the age at which children begin to consistently pass this type of task. Three different tasks were designed in which children played a game on one side of a table, and then were asked to choose a tool to play a similar game on the other side of the table the next day. For example, children used a toy fishing rod to catch magnetic fish on one side of the table; playing the same game from the other side of the table required a different type of fishing rod. At test, children chose between just 2 objects: the tool they had already used, which would not work on the other side, and a different tool that they had not used before but which was suitable for the other side of the table. Experiment 1: Forty-eight 4-year-olds (M = 53.6 months, SD = 2.9) took part. These children were assigned to one of two conditions: a control condition (present-self) where the key test questions were asked in the present tense and an experimental condition (future-self) where the questions were in the future tense. Surprisingly, the results showed that both groups of 4-year-olds selected the correct tool at above chance levels (Table 1 shows the mean number of correct answers out of three). However, the children could see the apparatus when they answered the test questions and so perhaps answered them correctly without imagining the future. Experiment 2: Twenty-four 4-year-olds (M = 53.7, SD = 3.1) participated. Pre-schoolers in this study experienced one condition: future-self looking-away. In this condition children were asked to turn their backs to the games when answering the test questions, which were in the future tense. Children again performed above chance levels on all three games.Contrary to the findings of Russell et al. (2010), our results suggest that episodic future thinking skills could be present in 4-year-olds, assuming that this is what is measured by the tasks. Table 1. Mean number of correct answers across the three games in Experiments 1 and 2Experimental Conditions (N=24 in each condition)Mean CorrectStandardDeviationStatistical SignificanceExp. 1 (present-self, look) – 2 items2.750.68p < 0.001Exp. 1 (future-self, look) – 2 items 2.790.42p < 0.001Exp. 2 (future-self, away) – 2 items 2.330.64p < 0.001Exp. 3 (future-self away) – 3 items1.210.98p = 0.157