ABSTRACT
Objective To explore how to apply the teaching mode combined flipped class with PBL teaching method to improve college students' ability of English reading and writing and the effectiveness of classroom. Methods In the class of college English reading and writing, students at grade 2015 were randomly divided into two groups. The experimental group (43 students) was adopted the class teaching with " flipped class and PBL teaching method"and the control group (43 students) was adopted traditional class teaching mode taught by the same teacher. The teaching effects of two groups were studied in a comparative way. The students' final grade, related data in the learning process, students'view of the two teaching modes are studied by analysis of basic data and questionnaire. Results At the end of the semester, the results of the experimental group are better than those of the control group. In the survey of the two class teaching modes, the students in the experimental group spent more time in the learning process than that of the control group.Students think that the teaching mode combined flipped class and PBL teaching method not only improves their autonomic learning ability, classroom participation, the English reading and writing ability, but also helps them perform better in the average scores in the final exam compared to the traditional classroom. Students are more satisfied with the new classroom teaching mode than with traditional one. Conclusion The teaching mode combined flipped class with PBL teaching method can promote the students'autonomous learning, contribute to absorb and internalize knowledge, improve the students'learning interest and learning efficiency, and improve teachers teaching ability.
ABSTRACT
Objective To study the chemical constituents from Bletilla ochracea. Methods The compounds were extracted by 95％ alcohol and isolated by column chromatography on silica gel and Sephadex LH-20. Their structures were identified by spectroscopic analysis (～1 H NMR and 13 CNMR).Results Nine compouds were obtained and identified as lusianthridin (1), 1, 2, 7-trihydroxy-4-methoxy-9, 10-dihydroxyphenanthrene (2), nudol (3), coelonin (4), batatasin Ⅲ (5), 3, 7-dihydroxy-2, 4-dimethoxyphenanthrene (6), daucosterol (7), β-sitosterol (8), stigmasterol (9).Conclus ion Compounds 2, 3, 5 were isolated from this plant for the first time.
ABSTRACT
Objective To study the bibenzyls and phenanthrenes from Arundina graminifolia.Methods The compounds were extracted by 95％ alcohol and isolated by column chromatography on silica gel and Sephadex LH-20.Their structures were identified by spectroscopic analysis (1H NMR and13CNMR).Results Eleven compouds were obtained and identified as batatasin Ⅲ (1),arundinanin (2),2,8-dihydroxy-4,7-dimethoxy-9,10-dihydrophenanthrene (3),shancidin (4),arundinan (5),isoshancidin (6),erianthridin (7),lusianthridin (8),eulophiol (9),flavanthrin (10),orchinol (11).Conclusion Compounds 3,7,9 were isolated from this plant for the first time.