【大学化学】doi: 10.12461/PKU.DXHX202404083
以一位考古学教授在四川自贡恐龙遗址考察引发的遐想为载体,介绍了U-Pb定年法的基本原理,以及样品采集、样品处理后的分析方法和检测结果处理,全面地科普了U-Pb定年法的相关知识。同时,本文介绍了自贡地区的恐龙文化及产业,向读者展现恐龙之都的魔力。
【大学化学】doi: 10.12461/PKU.DXHX202310090
借用拟人化、第一人称的手法,以Blog的形式对肽类激素催产素从基本概况、研究历史、功能作用等方面进行简要介绍,并与相关物质进行类比分析,用生动有趣的语言让人们对催产素形成初步的认识。
【大学化学】doi: 10.12461/PKU.DXHX202402006
维生素D,被誉为“阳光维生素”,在维护人体健康中具有不可或缺的作用。本文从化学角度出发,生动形象地介绍了维生素D的形成过程、发现过程、其在生物学上的功能以及在日常生活中的应用。通过深入了解维生素D,我们能更好地认识并学会如何合理利用这一重要营养素来维护自身健康。
【大学化学】doi: 10.12461/PKU.DXHX202405206
运用拟人化手法,生动形象地介绍抗生素的发现史、分类、作用机制、对人体的不良反应及使用抗生素的注意事项,旨在让读者在趣味阅读中了解有关抗生素的基础知识。
【大学化学】doi: 10.3866/PKU.DXHX202311093
动力学同位素效应是最近两年在国内外化学竞赛中出现的新兴考点。本文从势能曲线和零点振动能出发,从经典的过渡态理论角度阐释了一级动力学同位素效应和二级动力学同位素效应的起源,简述了动力学同位素效应在反应机理研究中的作用。通过解析国内外化学竞赛相关试题,分析了动力学同位素效应的考察角度,揭示了国内竞赛与国际竞赛的出题导向有一定的延续性。最后对动力学同位素效应的竞赛教学提出了一些思考和建议,对竞赛教学工作者具有参考和借鉴价值。
【无机化学学报】doi: 10.11862/CJIC.20240191
通过一种绿色、自交联策略,基于海藻酸钠(SA)和羧甲基纤维素钠(CMC)中羧基对Zn2+的离子缔合作用,利用旋涂法在锌电极表面原位构建了具有孔结构的柔性SA+CMC凝胶涂层(Zn@SA+CMC)。涂层中富含羟基,羟基的强吸附效应能够使涂层与锌电极紧密结合,减少界面处的副反应。柔性涂层不仅能适应锌电镀过程中的体积变化,还表现出较好的亲锌性,更低的成核过电压,更高的离子电导率,有利于Zn2+均匀沉积,有效抑制了锌枝晶的生成。因此,Zn@SA+CMC对称电池能稳定运行890 h(3 mA·cm-2);Zn@SA+CMC||MnO2全电池表现出优越的倍率和循环性能。
【大学化学】doi: 10.3866/PKU.DXHX202401007
复合固体推进剂是一种固体颗粒(氧化剂及金属燃料)填充高分子聚合物(粘合剂)的复合材料,是导弹、空间飞行器的各类固体发动机的动力源。本实验教学针对固体推进剂在载荷下容易发生“脱湿”,即粘合剂与填料表面之间分离,界面作用受到破坏的情况,通过可控自由基聚合设计了结构规整、分子量及组成可控的新型中性大分子键合剂,通过核磁氢谱及凝胶渗透色谱系统表征了其分子结构。本综合实验教学不仅加深了学生对固体推进剂领域的理解,提升了学生对于前沿高分子化学的基本原理及方法的认知,而且训练了学生的实验操作技能、大型仪器使用能力和结果分析能力,实现了前沿科学研究与国家重大需求在人才培养的结合。
【无机化学学报】doi: 10.11862/CJIC.20240392
AgVO3/ZIF 8 composites with enhanced photocatalytic effect were prepared by the combination of AgVO3 and ZIF-8. X-ray diffraction (XRD), scanning electron microscopy (SEM), high-power transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), ultraviolet-visible diffuse reflectance spectroscopy (UV-Vis DRS), photoluminescence (PL) spectroscopy, electron spin resonance (ESR) spectroscopy, transient photocurrent and electrochemical impedance spectroscopy (EIS) were used to characterize binary composites. Tetracycline (TC) was used as a substrate to study the performance efficiency of the degradation of photocatalysts under light conditions, and the degradation effect of TC was also evaluated under different mass concentrations and ionic contents. In addition, we further investigated the photocatalytic mechanism of the binary composite material AgVO3/ZIF-8 and identified the key active components responsible for the catalytic degradation of this new photocatalyst. The experimental results show that the degradation efficiency of 10% AZ, prepared with a molar ratio of 10% AgVO3 and ZIF-8 to TC, was 75.0%. This indicates that the photocatalytic activity can be maintained even under a certain ionic content, making it a suitable photocatalyst for optimal use. In addition, the photocatalytic mechanism of binary composites was further studied by the active species trapping experiment.
【无机化学学报】doi: 10.11862/CJIC.20230291
A new metal-organic framework (MOF) {[Cd(L)0.5(4, 4'-bpy)0.5]·H2O}n (1), where H4L=(1, 1': 4', 1″-terphenyl)-2, 2″, 4, 4″-tetracarboxylic acid, 4, 4'-bpy=4, 4'-bipyridine, was synthesized by hydro-solvothermal method. The structure of complex 1 was characterized by single-crystal X-ray diffraction, elemental analysis, powder X-ray diffraction, thermogravimetric analysis, and infrared spectrum analysis. The analysis of single crystal structure shows that 1 is a 3D structure, belonging to the monoclinic crystal system, C2/c space group. Cd(Ⅱ) connects L4- and 4, 4'-bpy to form a 2D plane structure, and the layers are connected by L4- to form a 3D network structure. The MOF shows good stability and can be used for the detection of tetracycline (TET) and p-nitrophenol (4-NP) by fluorescence quenching. The detection limits of TET and 4-NP were 0.15 and 0.062 μmol·L-1, respectively. In addition, the fluorescence quenching mechanism of 1 was also studied. 1 can be successfully applied to the determination of TET and 4-NP content in Yanhe water samples.
【无机化学学报】doi: 10.11862/CJIC.20230353
A metal - free photocatalyst was developed and synthesized through a single - step thermal treatment process involving banana peel (BP) and urea. The close interfacial connection between biomass-derived carbon (BC) and porous graphite carbon nitride (pg - C3N4) resulted in an increased specific surface area, expanded photo-response range, effective migration of photo-induced electrons, and enhanced stability. The reaction rate constant of pg-C3N4/BC for degradation oxytetracycline (OTC) in artificial seawater was 9.4 times higher than that of pristine pg-C3N4 after 70 min of visible-light illumination, and pg-C3N4/BC also performed better photocatalytic degradation on OTC in the continuous flow reaction process owing to facilitated photogenerated charge separation and transfer. Additionally, a potential photocatalytic mechanism was proposed to explain the enhanced performance of pg-C3N4/BC composites.
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