利用三步法（热溶剂还原法,硅烷化和氨基功能化）制备了Fe3O4@SiO2-NH2磁性纳米复合材料用于水体中全氟化合物的萃取,结合超高效液相色谱-串联三重四极杆质谱（UPLC-MS/MS）技术,建立了水体中7种典型全氟化合物的检测方法。通过扫描电镜（SEM）、透射电镜（TEM）和傅立叶红外光谱（FT-IR）等手段对材料进行表征,详细研究了解析溶剂、解析溶剂体积、解析时间、吸附时间和p H值等因素对萃取效率的影响。结果表明：氨基被成功修饰在Fe3O4@SiO2纳米粒子的表面,Fe3O4@SiO2-NH2磁性纳米材料对目标全氟化合物有较好的萃取效果,在萃取时间为20 min,解析溶剂为3 m L×4含0.28%氨水的甲醇,解析时间为5 min,p H 5.0时,萃取效率最佳。在最优实验条件下,全氟化合物的检出限为0.2~0.5 ng/L,线性范围为1~500 ng/L。方法用于实际水体中目标全氟化合物的检测,样品的加标回收率不低于82.0%。
新工科教育是我国加快推进科技强国而提出的重大教育政策,已在各工科高校中得以大力发展。基于“实践出真知”的教学理念,工科类高校中实验实践类课程的教学改革在新工科背景下备受关注和重视。河海大学的普通化学实验教学改革从现有课程教学中存在的教学内容质量不高,创新实验不足等问题出发,通过重组教材内容,融入课程思政内容,构建了面向不同专业的多层次教学体系,形成了“多层次、递进式”的实践教学模式,从历史共性和时代特性等多方面实践了思政教育理念。通过课程体系的改革与实践,提升了学生的自主探索兴趣和综合实践能力,为培养符合工程建设需求的新工科人才奠定了坚实基础。New engineering education is an important educational policy proposed by China to accelerate the promotion of science and technology, which has been vigorously developed in various engineering universities. Based on the teaching concept of “practice leads to true knowledge”, the teaching reform of experimental practice courses under the background of new engineering has attracted considerable attention. Due to the low quality of teaching content and insufficient innovative experiments in existing courses, the reform of general chemistry experimental teaching at Hohai University was carried out with the reconstruction of teaching content and the integration of curriculum thinking and policy, forming a “multi-level and progressive” practical teaching mode. The reform of general chemistry experimental teaching practiced the educational concept of curriculum thought and policy from many aspects, such as historical commonality and characteristics of the times. The reform and practice of the curriculum system could further enhance students’ interest in independent exploration and comprehensive practice, and lay a solid foundation for training new engineers to meet the needs of engineering construction.
