Abstract:

Experimental teaching， serving as a bridge between theoretical knowledge and practical competence， can deepen students’ understanding of theoretical concepts， and enhance their ability to solve complex problems， thereby playing a pivotal role in cultivating elite chemistry talents for the national innovation system. By understanding the laws of higher education development and innovative talent growth， the Chemistry Experiment Teaching Center of the College of Sciences at Northeastern University has innovatively proposed a closed-loop teaching model： “Construction Supports Competitions-Competitions Nurture Teaching-Teaching Promotes Learning”， aiming at the problem of difficult barrier between scientific research and pedagogy in talent development. This model is based on the requirements for cultivating top innovative talents， leveraging the practical feedback of disciplinary competitions， and creating a dynamic feedback mechanism of “Competition Incubation→Teaching Transformation→Competency Feedback”. Taking the award-winning project “Micro-Plasma Emission Spectrometer Setup and Trace Element Analysis Experiment” from the Chemistry Innovation Design Competition as an example， this study demonstrates the model’s breakthrough in traditional experimental teaching. Through a 4-class-hour experimental course， students independently construct a dielectric barrier discharge （DBD） micro atomic emission spectroscopy device， combined with hydride generation （HG） introduction technology to complete trace arsenic detection. The method showed a good linear relationship in the mass concentration range of 20-500 μg/L， with a coefficient of determination （R²） of 0.997. Teaching practice shows that students deepened their understanding of principles and made the instrument structure transparent through hands-on construction， promoting the improvement of teaching quality and providing a scalable innovative paradigm for the “high-order， innovative， and challenging” curriculum reform.

Key words: experimental teaching, innovation in teaching mode, construction of instrument devices, dielectric barrier discharge （DBD）