源起于发霉甜苜蓿，脱胎于生化实验室，华法林先生起初作为一种强力灭鼠毒药大杀四方。然而，在进入医药领域的道路上，他却因毒药的身份标签和种种流言而饱受质疑和反对。科学家们揭示了华法林抗凝血的机制，并证明了华法林抗凝治疗对患者的益处。从此，华法林先生以及他的衍生物们成为了抗凝治疗和防治鼠害的前线战士。

笔者在大学入学之初就受教于华彤文老师，后来跟随华老师做研究、搞教学、写教材，直至担任《大学化学》主编时依然听取华老师的教诲。在此文中分享40余年来近距离观察、感受和学习华老师严谨治学、勇于担当的教学与研究的态度和方法，期待我国的化学教育教学事业薪火相传，持续发展。

本文以紫甘蓝蔬菜为原料，进行了pH、金属离子和各种食品添加剂等一系列稳定性分析，探索紫甘蓝色素的最佳存储和使用环境。研究表明，紫甘蓝色素对pH敏感，随着pH增大，色素保留率逐渐减小;不同金属离子对紫甘蓝色素的稳定性也有影响，Fe³⁺会破坏紫甘蓝色素的结构，降低稳定性，保留率仅为8.68%;而Ca²⁺能提高其稳定性。添加剂蔗糖也可提高其稳定性，其中20 g·L^-1的蔗糖水溶液可将保留率提升至119.48%;而食盐、苯甲酸钠和山梨酸钾均会降低其稳定性。

以1，1′-二甲基-4，4′-联吡啶(甲基紫精，MV)二氯化物和Keggin型多酸单元合成的晶态材料(MV)₂[HPW^Ⅴ₂W^Ⅵ₁₀O₄₀]·2H₂O为催化剂，在无有机溶剂、室温条件下合成了一系列β-氨基醇类化合物。该催化剂不仅能够高效催化β-氨基醇的合成，而且具有良好的稳定性及可回收性。经过6次循环使用后，催化剂活性未出现明显下降，表明其具有较好的循环利用潜力。与传统方法相比，该反应体系不使用有机溶剂并具有反应条件温和、操作简单、环境友好等优点。

Two new viologen-polyoxometalate hybrid crystalline materials: (MV)₂[HPW₂^ⅤW₁₀^ⅥO₄₀] ·2H₂O (1) and (EV)₂[Mo₈O₂₆] (2) have been synthesized by using the cations of 1, 1'-dimethyl-4, 4'-bipyridinium dichloride (methyl viologen, MV) and 1, 1'-diethyl-4, 4'-bipyridinium dibromide (ethyl viologen, EV) as the electron acceptors, and the electron-rich polyoxometalate anions as the electron donors. The structures of compounds 1 and 2 have been determined by single-crystal X-ray crystallography. Hydrogen bond interactions exist between the cations and the anions in 1 and 2. Interestingly, 2 has a photochromic performance with a light response time within 1 min. The photochromic mechanism of compound 2 has been investigated by solid-state diffuse reflection, electron paramagnetic resonance and theoretical calculation. 1 and 2 show good catalytic performance in the photocatalytic degradation of several organic dyes (methylene blue, pararosaniline hydrochloride and rhodamine 6G).

Under the condition of solvothermal synthesis, the viologen ligand 1, 1′‐bis(3‐carboxyphenyl)‐(4, 4′‐bipyri‐ dine) dichloride (H₂bcbpy·2Cl) and KI are coordinated with the metal cadmium ions. A case of thermochromic coor‐ dination polymer [Cd(bcbpy)I₂] ·2H₂O (1) was constructed. Complex 1 displays a 1D chain structure and exhibits thermochromic behavior. Under different temperature stimulation, the complex (ground) slowly changed from green to yellow‐green, and with the increase of temperature, the color of complex 1 gradually deepened, and finally became orange‐yellow. Therefore, complex 1 was prepared as a thermochromic film. In addition, we also performed electrochemical tests on complex 1, which showed that the complex is a semiconductor material.