影响大学生学业成绩的四个重要非智力因素

In the present study, 520 questionnaires about general self–efficacy, achievement goal orientation, learning motivation and time management were delivered to university students. The students were randomly chosen from Communication University of China, Central University of Finance and Economics, Capital University of Business and Economics and Shanxi University. 495 responses were valid , in which 225 majoring in liberal arts and 270 majoring in natural sciences. The influences of these four factors on students’ academic achievements were explored. And the gender differences in General self-efficacy, achievement goal orientation, learning motivation and time management were analyzed in the present study too. It was found that: 1) There were gender difference on academic achievements. The scores’ of female students were higher than males’. 2) Significant gender differences were found in four considered factors which indicated that female students got higher scores than male students; 3) There were close relations between the four considered factors and students’ academic achievements. There were also obvious relations among the four factors. 4) University students’ academic achievements could be well predicted by their general self-efficacy, achievement goal orientation, learning motivation and time management.

Catalytic oxidation of chlorobenzene on supported manganese oxide catalysts

Total oxidation of chlorinated aromatics on supported manganese oxide catalysts was investigated. The catalysts have been prepared by wet impregnation method and characterized by XRD and TPR. Among the catalysts with the supports of TiO(2), Al(2)O(3) and SiO(2), titania supported catalyst (MnO(x)/TiO(2)) gives the highest catalytic activity. MnO(x)/TiO(2) (Mn loading, 1.9 wt.%) shows the total oxidation of chlorobenzene at about 400 degreesC. The activity can be stable for over 82 h except for the first few hours. At lower Mn loadings for MnO(x)/TiO(2), only one reduction peak appears at about 400 degreesC due to the highly dispersed manganese oxide. With the increase of Mn loading, another reduction peak emerges at about 500 degreesC, which is close to the reduction peak of bulk Mn(2)O(3) at 520 degreesC. TPR of the used catalyst is totally different from that of the fresh one indicating that the chemical state of the active species is changed during the chlorobenzene oxidation. The characterization studies of MnO(x)/TiO(2) showed that the highly dispersed MnO(x) is the precursor of the active phase, which can be converted into the active phase, mainly oxychlorinated manganese (MnO(y)Cl(z)), under working conditions of chlorobenzene oxidation. (C) 2001 Elsevier Science B.V. All rights reserved.