Well‐Defined Flowerlike NdOCl Nanostructures: Nonaqueous Sol–Gel Synthesis,Nanoscale Characterization and Their Magnetic and Photoluminescence Properties

A facile nonaqueous solution route for the fabrication of NdOCl nanostructures based on a ligand‐exchange protocol and further thermal decomposition in organic medium, using only chloride salt as the neodymium source, is reported and the formation mechanism is proposed. The morphology, crystal structure, and chemical compositions of the sample were characterized at the nanoscale. XRD results and selected‐area electron diffraction patterns show that the sample is purely tetragonal NdOCl without any other impurity phases. TEM results show that the NdOCl nanostructures have a well‐defined flowerlike shape, which looks like a chrysanthemum just about to bloom. Magnetization measurements reveal that the NdOCl nanoflowers show room‐temperature ferromagnetism. The photoluminescence properties were also studied. These results are significant for fundamental research and promising applications of rare‐earth‐based nanostructures.     

Glucose detection at attomole levels using dynamic light scattering and gold nanoparticles

Glucose is directly related to brain activity and to diabetes.Therefore,developing a rapid and sensitive method for glucose detection is essential.Here,label-free glucose detection at attomole levels was realized by detecting the average diameter change of gold nanoparticles(AuNPs)utilizing dynamic light scattering(DLS).Single-strand DNA(ssDNA)adsorbed into the AuNPs’surfaces and prevented them from aggregating in solution that contained NaCl.However,ssDNA cleaved onto ssDNA fragments upon addition of glucose,and these fragments could not adsorb onto the AuNPs’surfaces.Therefore,in high-salt solution,AuNPs would aggregate and their average diameter would increase.Based on monitoring the average diameter of AuNPs with DLS,glucose could be detected in the range from 15 pmol/L to 2.0 nmol/L,with a detection limit of 8.3 pmol/L.Satisfactory results were also obtained when the proposed method was applied in human serum glucose detection.     

A bifunctional,colorimetric and fluorescent probe for recognition of Cu2+ and Hg2+ and its application in molecular logic gate

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New Conjugated Molecules with Two and Three Dithienyldiketopyrrolopyrrole (DPP) Moieties Substituted at meta Positions of Benzene toward p‐ and n‐Type Organic Photovoltaic Materials

Two conjugated molecules, TADPP3 and TADPP2‐TT , are reported, in which three and two dithienyldiketopyrrolopyrrole (DPP) moieties, respectively, are substituted at the meta positions of benzene. Based on cyclic voltammetry and absorption data, TADPP3 and TADPP2‐TT possess similar HOMO and LUMO energies of about ?5.2 and ?3.4 eV, respectively. Thin films of TADPP3 and TADPP2‐TT exhibit p‐type semiconducting behavior with hole mobilities of 2.36×10^?3 and 3.76×10^?4 cm² V^?1 s^?1 after thermal annealing. Molecules TADPP3 and TADPP2‐TT were utilized as p‐type photovoltaic materials to fabricate organic solar cells after blending with phenyl C₇₁ butyric acid methyl ester ( PC₇₁BM ) and phenyl C₆₁ butyric acid methyl ester ( PC₆₁BM ). The relatively low J_SC and fill factor values can be attributed to poor film morphologies based on AFM and XRD studies. A solar cell with a thin film of TADPP3 with PC₇₁BM in a weight ratio of 1:2 exhibits a high open‐circuit voltage (V_OC) of 0.99 V and a power conversion efficiency (PCE) of 2.47 %. Interestingly, TADPP3 can also be employed as an n‐type photovoltaic material. The blended thin film of TADPP3 with P3HT in a weight ratio of 1:2 gave a high V_OC of 1.11 V and a PCE of 1.08 % after thermal annealing.     

A Single Molecular Diels–Alder Crosslinker for Achieving Recyclable Cross‐Linked Polymers

A triol‐functional crosslinker combining the thermoreversible properties of Diels–Alder (DA) adducts in one molecule is designed, synthesized, and used as an ideal substitute of a traditional crosslinker to prepare thermal recyclable cross‐linked polyurethanes with excellent mechanical properties and recyclability in a very simple and efficient way. The recycle property of these materials achieved by the DA/retro‐DA reaction at a suitable temperature is verified by differential scanning calorimetry and in situ variable temperature solid‐state NMR experiments during the cyclic heating and cooling processes. The thermal recyclability and remending ability of the bulk polyurethanes is demonstrated by three polymer processing methods, including hot‐press molding, injection molding, and solution casting. It is notable that all the recycled cross‐linked polymers display nearly invariable elongation/stress at break compared to the as‐synthesized samples. Further end‐group functionalization of this single molecular DA crosslinker provides the potential in preparing a wide range of recyclable cross‐linked polymers.

     

分子量条带用蛋白质

蛋白质的生物化学、生物物理学及化学生物学研究中,凝胶电泳是常见且重要的分析手段。然而其背后所蕴含的一众有关蛋白质结构及功能的知识点长期被国内外本科相关专业教学忽略。从探讨蛋白质凝胶电泳的分子量指示物的筛选标准出发,分析比较了几类常见的分子量指示物,并基于一级结构和高级结构的稳定性对分子量条带用蛋白质的筛选提出了一些合理的推论。     

促进学生化学学科核心素养发展的“铁盐和亚铁盐”的单元教学

设计了“铁盐和亚铁盐”的单元教学,以“探究硫酸亚铁的性质”和“线路板腐蚀液的研究”为核心任务,把铁盐与亚铁盐的性质、Fe²⁺和Fe³⁺的相互转化等核心知识贯穿其中,建立从物质类别、元素价态视角研究物质性质及转化的思路方法,促进多维度化学学科核心素养的融合发展。经过多轮次教学改进,结合教学实践过程及其教学效果抽提出“注重应用无机物的认识模型,重点把握研究物质性质的角度和思路”“抓住典型活动,培养学生的关键能力”“设计开放性任务,通过有效的师生对话进行诊断,外显问题解决思路”等教学策略。     

电极电势:从电化学势说起*

对于原电池,电极电势的本质是化学体系对电极材料上电子势能的影响,其正负极电势差反映化学能向电能转化的趋势。电极界面上化学物质的氧化/还原反应是通过何种途径影响到电极上电子势能的,现有的教材和论著没有给出明确的解释。本文基于相间电化学势平衡原则阐明了固液界面上离子平衡与电极上电子电势的关系,并由此给出了标准电势的物理含义:它是构成电极体系一系列物性参数的组合,包括被测电极的电子、离子化学势,工作电极电解液的离子化学势,参比电极的电子、离子化学势和参比电极电解液的离子化学势等。     

有机化学教学中的“三融合、二反思、四进阶”创新教学模式*

为培养出新时代创新人才,构建的“三融合、二反思、四进阶”教学模式有效提升了学生们科技创新能力。依据有机化学特点,创设科学发现情境,通过核心知识点网融合(挑战度)、理论实践交叉融合(高阶性)和化学思政融合(课程思政)“三融合”策略,不断激发学生们学习兴趣;通过教师反思、学生反思的“二反思”过程不断优化教学过程,改善教学效果;最终使具有不同知识层次的学生通过“四进阶”教学策略逐步提升科创能力(创新性)。     

“四模块”嵌入下的混合式教学设计与实践*——以功能材料专业物理化学基础课程为例

为建设适应新时代要求,突出高阶性、创新性、挑战度的一流本科课程,实现价值引领、能力培养和知识传授的教育教学目标,结合功能材料专业的特点和民族高等院校学生的学情,构建了物理化学基础课程的“四模块、三阶段、两时空、双平台”的混合式教学新模式,重塑了“价值引领模块、基础理论模块、多学科融合模块和虚拟仿真实验模块”的“四模块”内容体系。通过“四模块”嵌入下的混合式教学实践研究,结合学生的课前、课中、课后等学习成绩,多维度评价学习效果,并藉由调查问卷来分析学生对混合式教学的评价,最终研究结果表明学生的个性化自主学习能力有了显著提高、学生运用物理化学理论解决复杂问题的综合能力得到了提升,学生经过刻苦学习获得了素质提高的成就感。