李正名院士是我国著名的教育家、化学家和农药学家。在李先生逝世3周年之际，李正名奖学金捐赠暨首届颁奖仪式在南开大学举行。本文结合一部分典型的具体事例，对李正名先生的教育家精神和科学家精神进行了介绍，从中折射出他始终如一的坚定爱国信念和无私奉献精神。青年学子通过学习李先生的光辉事迹，可以深入了解老一辈科学家浓厚的家国情怀。本文有助于激励当代大学生厚植爱国主义理想与信念，增强自主创新意识和能力，立志为中华民族的伟大复兴贡献自己的全部力量。

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.

A novel viologen-based photochromic coordination polymer, namely [Zn(CV)_0.5(BDC)(H₂O)]·2H₂O (1), has been successfully constructed via solvothermal self-assembly of Zn²⁺ ions with the 1, 1′-bis(2-carboxyethyl)-4, 4′-bipyridinium ((H₂CV)²⁺) as a photo-responsive functional unit and terephthalic acid (H₂BDC) as an auxiliary bridging ligand. Single-crystal X-ray diffraction analysis reveals that complex 1 features a 1D chain-like framework. Upon light irradiation, complex 1 exhibited a distinct photo-responsive color-changing behavior, transforming from colorless to blue. The blue-colored sample gradually faded and reverted to its original colorless state upon being placed in a dark environment at room temperature, demonstrating excellent reversible photochromic properties. On the basis of its photochromic performance, the application of this complex in ink-free printing has been explored. Furthermore, complex 1 emitted blue light under UV irradiation in a dark environment, revealing favorable photoluminescent characteristics. In addition, complex 1 possessed multiple photoswitchable properties.

通过溶剂热法将1,1′-二甲基-4,4′-联吡啶阳离子(甲基紫精阳离子，MV²⁺)和1,1′-二乙基-4,4′-联吡啶阳离子(乙基紫精阳离子，EV²⁺)引入金属有机框架Zn-NH₂-BDC中，得到2种紫精修饰的金属有机框架{(MV)[Zn₂(NH₂-BDC)₃]}_n (1)、{(EV)[Zn₃(NH₂-BDC)₄]}_n (2)(NH₂-H₂BDC=2-氨基对苯二甲酸)。2个配合物展现出良好的催化性能，在温和反应条件下，能够高效、稳定地一锅法催化Knoevenagel缩合-Michael加成环化反应，生成4H-吡喃衍生物，产率均达到98%以上。在回收利用方面，2种材料可重复使用至少5次，并保持其原有催化活性。

循环伏安法(CV)是利用电化学方法研究氧化还原反应的关键表征手段之一。传统的循环伏安法教学实验中往往未能深入探讨CV曲线反映的物理化学过程，导致学生对CV表征过程中电化学动力学行为的理解停留在表面。为了弥补这一缺陷，本实验利用Python语言编写了CV数字化仿真程序，对CV曲线和电极表面的电活性物质浓度变化过程进行了可视化仿真。这一数字化设计不仅减少了实验材料的消耗，提高了实验效率，而且通过动态可视化的形式，使枯燥的电化学数据转化为直观易懂的图像。本数字化仿真实验对传统实验进行了有益的补充和提升，提高了教学的互动性和学生的参与度，激发了学生对电化学知识的学习兴趣和探索欲望。