Assessing fraction knowledge by a digital game

Serious or educational games gain increasing research interest as tools to augment traditional instructional approaches on scholastic learning, especially in mathematics education. In this study, we investigated whether game-based approaches may not only be useful to foster numerical learning but may also be valid as an assessment tool. To measure their conceptual knowledge of fractions eleven-year-old students played a math game on tablet computers using tilt-control to navigate an avatar along a number line for a total of 30 min. Findings indicated that hallmark effects of fraction magnitude processing typically observed in basic research, such as the numerical distance effect, were successfully replicated using the game-based assessment. Moreover, fraction comparison performance as well as fraction estimation accuracy correlated significantly with students' math grades. Therefore, the results of the current study suggest that game-based learning environments for fraction education (even using tilt-control) may also allow for a valid assessment of students’ fraction knowledge.     

大庆原油馏分与复合体系界面活性及乳化性研究

为考察原油成分对复合体系界面活性的影响，将原油通过实沸点蒸馏法切割成不同的馏分，对各馏分与三元体系的动态界面张力进行了测定。还探讨了馏分油的乳化液稳定性及重组分对乳化液稳定性的影响。研究结果表明：与三元体系的界面张力，轻馏分最低，其次是重组分，再次是沸点依次升高的中间馏分；在轻馏分中加入重组分可以进一步降低界面张力；馏分油与二元（ Ａ／Ｓ） 体系形成的乳状液，其稳定性随馏分沸点升高而降低，加入重组分可提高乳状液的稳定性。