研究性与系统性相结合的有机合成实验教学实践

为了培养学生的创新能力和实践能力,使学生较全面地掌握有机合成实验理论知识和实验技能,开展了有机合成实验研究性和系统性结合的教学探索和实践。在课程建设和教学过程中,贯彻以学生为主体的教学改革思路与方法。从教学内容和模式、授课方式、考核方式等多个教学环节进行探索研究,科教融合,结合实际课堂教学,倡导启发式教学方法。研究型教学模式的实施有效地调动了学生自主研究性学习的积极性,有利于提高学生的综合实践能力,促进实验教学与科学研究的衔接。     

TPE based aggregation induced emission fluorescent sensors for viscosity of liquid and mechanical properties of hydrogel

Two amphiphilic TPE E/Z isomers with aggregation induced emission(AIE) property have been synthesized and characterized. The logarithmic fluorescent intensity of the two molecules was in positive relationship with logarithmic viscosity of liquid. To note, the Z-TPE isomer exhibited more sensitivity in the viscosity of liquid sensing in comparison with the corresponding E-TPE counterpart(around 1.80 folds).Furthermore, two molecules could be used as fluorescent sensors for mechanical properties(v...     

Immobilization of glucose oxidase with the blend of regenerated silk fibroin and poly(vinyl alcohol) and its application to a 1,1′- dimethylferrocene-mediating glucose sensor

The structure and properties of the blend of regenerated silk fibroin (RSF) and poly(vinyl alcohol) (PVA) were investigated. The two polymers in the blend are in the state of phase segregation. Infrared (IR) spectra indicate that the RSF in the blend maintains its intrinsic properties, thus, ethanol treatment can transfer silk I structure of RSF to silk II structure. The water absorption property and mechanical property of the blend are improved in comparison with those of RSF. The blend maintains the major merit of RSF, that is, it can immobilize glucose oxidase on the basis of the conformational transition from silk I structure to silk II structure. The properties of the immobilized enzyme are examined. Moreover, the second generation of glucose sensor based on the immobilized enzyme is fabricated and it has a variety of advantages including easy maintenance of enzyme, simplicity of construction, fast response time and high stability.     

Advances in Electrochemical Decarboxylative Transformation Reactions

Owing to their non-toxic, stable, inexpensive properties, carboxylic acids are considered as environmentally benign alternatives as coupling partners in various organic transformations. Electrochemical mediated decarboxylation of carboxylic acid has emerged as a new and efficient methodology for the construction of carbon-carbon or carbon-heteroatom bonds. Compared with transition-metal catalysis and photoredox catalysis, electro-organic decarboxylative transformations are considered as a green and sustainable protocol due to the absence of chemical oxidants and strong bases. Further, it exhibits good tolerance with various functional groups. In this Minireview, we summarize the recent advances and discoveries on the electrochemical decarboxylative transformations on C−C and C−heteroatoms bond formations.     

Mechanically strong and stiff supramolecular polymers enabled by fiber reinforced long-chain alkane matrix

Fiber-reinforced-concrete (FRC) mechanism refers short discrete fibers that are uniformly distributed and randomly oriented, which offers an effective way to improve the mechanical performance of concrete. In the design of supramolecular polymers, an analogous concept of FRC appears to have been considered very rarely-although fibrous structure has been frequently observed/generated during the supramolecular polymerization. In this work, we apply the alkane thermosets, octadecane (C₁₈H₃₈) and tetracosane (C₂₄H₅₀), taking the role of “concrete”, and the low-molecular-weight monomer with long alkyl chains as the essential “fiber” component, to fabricate the “fiber reinforced supramolecular polymer”. Very much like FRC mechanism in material science, the resulting fiber reinforced supramolecular polymer thus exhibit unusually high mechanical strength and stiffness, which is unprecedented in the conventional supramolecular strategy.     

Cell-Penetrating Mitochondrion-Targeting Ligands for the Universal Delivery of Small Molecules,Proteins and Nanomaterials

Mitochondria are key organelles that perform vital cellular functions such as those related to cell survival and death. The targeted delivery of different types of cargos to mitochondria is a well-established strategy to study mitochondrial biology and diseases. Of the various existing mitochondrion-transporting vehicles, most suffer from poor cytosolic entry, low delivery efficiency, limited cargo types, and cumbersome preparation protocols, and none was known to be universally applicable for mitochondrial delivery of different types of cargos (small molecules, proteins, and nanomaterials). Herein, two new cell-penetrating, mitochondrion-targeting ligands (named Mito^Ligand) that are capable of effectively “tagging” small-molecule drugs, native proteins and nanomaterials are disclosed, as well as their corresponding chemoselective conjugation chemistry. Upon successful cellular delivery and rapid endosome escape, the released native cargos were found to be predominantly localized inside mitochondria. Finally, by successfully delivering doxorubicin, a well-known anticancer drug, to the mitochondria of HeLa cells, we showed that the released drug possessed potent cell cytotoxicity, disrupted the mitochondrial membrane potential and finally led to apoptosis. Our strategy thus paves the way for future mitochondrion-targeted therapy with a variety of biologically active agents.     

Ultrafast synthesis of near-infrared-emitting aqueous CdTe/CdS quantum dots with high fluorescence

The traditional aqueous route to synthesis CdTe/CdS Core/shell (c/s) quantum dots (QDs) via decomposition of Cd-thiol complexes is usually time consuming. Herein, an ultrafast and facile aqueous synthetic approach under atmospheric pressure for CdTe/CdS c/s QDs with emission from the green to the near-infrared window (535–820 nm) is reported. With purified CdTe core QDs diluted in solution of Cd-3-mercaptopropionic acid (MPA) complexes, CdTe/CdS c/s QDs with emission wavelengths at 700 and 800 nm can be obtained within 20- and 45-min refluxing under the optimized experimental conditions, respectively. This is the most rapid way to prepare CdTe/CdS c/s QDs in aqueous phase, and the obtained QDs were highly luminescent without postsynthesis treatment. The influences of various experimental factors, including Cd²⁺ concentration, MPA-to-Cd ratio, pH value, and dilution ratio on the growth rate and luminescent properties of the obtained CdTe/CdS c/s QDs, have been taken into consideration. The three processes “purification-dilution-addition” ensure the synthesis environment with high pH value and low core concentration and have a marked impact on the rapid synthesis rate and the resulting high fluorescence of CdTe/CdS c/s QDs.     

电化学条件下富电子芳烃的C—H官能团化实现烯烃的1,2-二芳基化

传统的烯烃二芳基化主要手段是,先通过过渡金属催化的芳基亲电试剂与烯烃发生交叉偶联,然后再与芳基亲核试剂发生反应[1].但是这种反应策略存在原子经济性低及反应步骤多的缺点.因此急需发展一种高效、高原子经济性的合成方法来实现烯烃的二芳基化.2015年,Bunel/Lei课题组[2]报道了FeCl3/2,3-二氯-5,6-二...     

丙烷脱氢制丙烯研究进展

介绍了丙烷脱氢制丙烯的研究现状。包括丙烷催化脱氢的热力学、脱氢技术丙烷在膜反应器中脱氢及以氧气和二氧化碳作氧化剂的丙烷氧化脱氢。     

化学教育与环保教育

当今,环境保护已为举世瞩目的重大课题,它既需要高新科学技术与理论,又需全体公民的环境教育,中国是发展中国家,环保尤为重要,环境教育应为中学化学教学的重要内容。一、从“环境危机”看环境教育的重要性环境污染,生态失衡,今天正日益严重地威胁着全人类的生存,人类只有一个地球,“环境保护”正唤起人类行动起来,爱护环境,保护家园。值得我们警惕的是：我国西部兰州上空已出现浓重光化学烟雾;我国长江以北地区竟已找不到一条未被污染的主要河流;重庆、贵阳等地近几年常有大量酸雨降落…。环保部门指出：目前我国环境污染程度…