【大学化学】doi: 10.12461/PKU.DXHX202406038
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。
【大学化学】doi: 10.3866/PKU.DXHX202312021
“荧光海”是指在夜晚或黑暗环境中,海水表面发蓝光的景象,又称“蓝眼泪”。本科普实验着眼于引导人们了解该有趣自然现象,探究背后的科学原理,以智能缓释材料海藻多糖水凝胶包埋发光原料,根据化学发光能量转移原理制备可持续发光的多彩藻胶球,并基于此推出一种便携科普实验盒,可随时随地重现属于自己的澎湃“蓝眼泪”。本科普实验将糖化学、光化学和材料化学知识应用于自然现象的解读与应用,向公众充分展现浪漫美妙的化学科学。
【无机化学学报】doi: 10.11862/CJIC.20240255
采用原位聚合法制备了氯氧化铋(BiOCl)与聚苯胺(PANI)复合的Ⅱ型异质结光催化剂BiOCl/PANI,并采用X射线衍射(XRD)、傅里叶变换红外光谱(FTIR)、透射电子显微镜(TEM)、X射线光电子能谱(XPS)、紫外可见漫反射光谱(UV-Vis DRS)和N2吸附-脱附测试等多种技术手段对其进行了表征,考察了BiOCl/PANI在模拟可见光下对罗丹明B (RhB)的光催化降解性能。实验结果表明:BiOCl/PANI催化剂比PANI和BiOCl具有更高的光催化活性,在RhB质量浓度为50 mg·L-1、PANI与BiOCl的物质的量之比为0.02∶1、50 mg·L-1的催化剂条件下,所制备的BiOCl/PANI光催化150 min后,RhB降解率为98.8%,速率常数为0.031 min-1;经过4次循环实验后,RhB降解率从98.8%降低至98.4%,表现出良好的稳定性和可重复利用性。光催化剂BiOCl/PANI实现了电子和空穴对的快速分离,降低了二者在催化剂内部的复合速率,提高了光催化性能。
【大学化学】doi: 10.12461/PKU.DXHX202405147
仪器分析实验“分子荧光法测定罗丹明B的含量”存在实验过于简单、未考虑实际情况等问题。因此,本改进实验在三维荧光扫描模式下获取样本数据,不进行复杂预处理,而是运用化学计量学算法解析出目标分析物的纯信号,进而实现了染色辣椒中罗丹明6G和123的同时测定。本改进实验提高了学生全面考虑问题和创新解决问题的能力。
【无机化学学报】doi: 10.11862/CJIC.20240428
通过微波加热方式,快速合成了3个葡萄糖修饰的双席夫碱。通过比浊度分析、HRP/Amplex Red实验、DCFH-DA荧光探针实验、NBT分析法以及MTT实验检测它们抑制金属离子诱导的Aβ聚集、减少活性氧(ROS)生成及抑制Aβ聚集产生的细胞毒性。发现葡萄糖修饰的双席夫碱都能有效抑制金属离子(Zn2+、Cu2+)诱导的Aβ1~40的聚集,降低Cu2+-Aβ加合物催化产生ROS水平、提高Cu2+-Aβ作用的细胞内超氧化物歧化酶的活力,有效抑制Zn2+或Cu2+诱导Aβ聚集而产生的神经细胞毒性并大幅提高细胞存活率。作为对比,我们也检测了相同条件下的氯碘羟喹(cliquinol, CQ)和没有葡萄糖修饰的同类双席夫碱的活性,发现葡萄糖修饰的双席夫碱各方面活性均好于CQ;葡萄糖修饰的双席夫碱自身毒性小、抗氧化和提高Aβ与金属离子共同处理的细胞的存活率方面均优于未葡萄糖官能化的同类双席夫碱。
【无机化学学报】doi: 10.11862/CJIC.20240219
A simple two-step hydrothermal method synthesized four different CdS/Fe3O4 photocatalysts with varying ratios of mass of CdS to Fe3O4. The composition and morphology of the prepared samples were investigated using X-ray diffraction (XRD), Raman spectrum, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Solid UV reflectance spectra testing found that CdS/Fe3O4 nanocomposites had good light absorption throughout the spectral range, promoting their photocatalytic properties. Under visible light irradiation, CdS/Fe3O4 (2:5) with a mass ratio of 2:5 exhibited excellent photocatalytic performance, with a degradation rate of 98.8% for rhodamine B. Furthermore, after five cycles of photocatalytic degradation reaction, the rhodamine B degradation rate remained at 96.2%, indicating that the photocatalysts have good photocatalytic stability.
【无机化学学报】doi: 10.11862/CJIC.20250028
A flower-like BiOBr photocatalyst (CS/BiOBr) was prepared by using the carbon material derived from corn straw (CS) as the carrier. The prepared composites were characterized by X - ray diffraction (XRD), Fourier transform infrared (FIIR) spectra, scanning electron microscope (SEM), X - ray photoelectron spectra (XPS), and UV-Vis diffuse reflectance spectra (UV-Vis DRS). The SEM analyses indicate that the introduction of CS promotes the formation of a unique flower-like structure in BiOBr, which not only optimizes the efficiency of light capture but also increases the specific surface area of BiOBr. The bandgap of the composite was narrower compared with the pure BiOBr. The CS/BiOBr composites exhibited higher photocatalytic activity than pure CS and BiOBr under visible light irradiation, and a higher first-order reaction rate constant (k) of 0.043 7 min-1 than BiOBr (0.014 6 min-1), and exhibited excellent stability and reusability during the cyclic run. The enhanced photocatalytic activity is attributed to the efficient separation of photoinduced electrons and holes. Superoxide radicals and holes were the major active species.