废旧聚酯（PET）的化学循环利用

废旧PET 聚酯可通过化学解聚来实现其循环利用。本文总结了废旧PET 聚酯化学循环利用领域的研究现状, 介绍了目前国内外开发的主要化学解聚工艺方法, 包括水解法、甲醇解聚法、乙二醇解聚法等, 同时对各种工艺过程的优缺点进行了综合比较。     

High performance of N,P co-doped metal-free carbon catalyst derived from ionic liquid for oxygen reduction reaction

Journal of Solid State Electrochemistry - One-pot strategy to fabricate N, P co-doping carbon was developed based on the functional ionic liquid (IL) as the N, P, and C precursors. The IL featuring...     

The enhanced electronic communication in ferrocenemethanol molecular cluster based on intermolecular hydrogen-bonding

The electronic communication has been enhanced by regulating the intermolecular hydrogen-bonding in ferrocenemethanol molecular clusters. This enhanced electronic communication facilitates the electron transfer of ferrocenemethanol and increases the standard rate constant of the electron transfer process.     

Enhanced electrochemical performance of SnS nanoparticles/CNTs composite as anode material for sodium-ion battery

SnS/CNTs composite as anode for SIBs exhibits high reversible capacity, good cyclability as well as rate performance, which is superior to that of pure SnS. The enhanced electrochemical performance can be attributed to the adding of CNTs as a flexible and conductive structure supporter and the formation of SnS nanoparticles with small diameter.     

Syntheses,crystal structures,and properties of two dinuclear iron(III) complexes constructed with 1,2,3,5-benzenetetracarboxylic acid and chelating N-donor auxiliary coligands

Two dinuclear Fe(III) metal–organic complexes with tetracarboxylate and chelating N-donor ligands, [Fe(Hbtec)(phen)(H₂O)]₂·2H₂O (1) and [Fe(Hbtec)(bpy)(H₂O)]₂·2H₂O (2) (H₄btec = 1,2,3,5-benzenetetracarboxylic acid, phen = 1,10-phenanthroline, bpy = 2,2′-bipyridine) have been prepared and characterized by elemental analysis, IR spectroscopic, and X-ray diffraction methods. Both complexes crystallize in the monoclinic space group P2₁/c with two Fe(III) ions bridged by two Hbtec^3? ligands into a dinuclear unit. Hydrogen bonding connects the dinuclear units into a 3-D framework. The dinuclear units are 10-connected nodes that produce a 3-D framework with topology Schläfli symbol as (3¹²·4²⁸·5⁵). Thermal stabilities and luminescent properties of the two complexes have also been investigated.     

A Crosslinked Nucleic Acid Nanogel for Effective siRNA Delivery and Antitumor Therapy

Functional siRNAs are employed as cross‐linkers to direct the self‐assembly of DNA‐grafted polycaprolactone (DNA‐g‐PCL) brushes to form spherical and nanosized hydrogels via nucleic acid hybridization in which small interfering RNAs (siRNAs) are fully embedded and protected for systemic delivery. Owing to the existence of multivalent mutual crosslinking events inside, the crosslinked nanogels with tunable size exhibit not only good thermostability, but also remarkable physiological stability that can resist the enzymatic degradation. As a novel siRNA delivery system with spherical nucleic acid (SNA) architecture, the crosslinked nanogels can assist the delivery of siRNAs into different cells without any transfection agents and achieve the gene silencing effectively both in vitro and in vivo, through which a significant inhibition of tumor growth is realized in the anticancer treatment.     

Enantioselective approach to indolizidine and quinolizidine scaffolds. Application to the synthesis of peptide mimics

An enantioselective approach to substituted indolizidine and quinolizidine frameworks has been developed. Key steps of the synthesis are the enantioselective, palladium-catalyzed N-allylation of an imide, the nucleophilic allylation of an acyliminium ion and a ring closing metathesis. This general strategy has been applied to the synthesis of indolizidine peptide mimics, starting from a chiral imide derived from l-aspartic acid. It was observed that the preexisting stereogenic center of this substrate has a moderate influence on the stereoselectivity of the electrophilic allylation, which is mainly determined by the sense of chirality of the catalyst.     

无患子三萜皂苷研究进展

无患子是一种集工业、药用、观赏、生态于一体的多功能综合利用价值极高的经济树种,近年来,由于其具有较高的商业价值和药理活性,受到了广泛的重视。迄今文献中报道的无患子中分离鉴定的三萜皂苷类化合物有71种,具有抗菌、抗肿瘤、保护心脑血管、保护肝脏、抗生育、杀虫等多种生物活性和良好的非离子表面活性作用,在医药、食品保健、日化和农业等领域应用前景广阔。本文对其皂苷的种类、提取与分离及其应用进行了综述,以期为今后无患子的研究、开发与利用提供参考。     

固态反应制备纳米钙钛矿型物质及其反应机理

以TiCl₄和碱土金属氢氧化物为原料, 采用低温固态反应合成了钙钛矿纳米晶. 首先, TiCl₄水解制备高活性TiO₂•H₂O (H₂TiO₃), 再分别与碱土金属氢氧化物按物质的量比1∶1均匀混合研磨1 h后, 在一定温度下反应. XRD分析显示产物均为钙钛矿型物质. TEM形貌观察, 粒子均匀, 分散性较好, 平均粒径小于80 nm. 通过对不同反应温度和反应时间产物的XRD分析推断出了化学反应为该低温固态反应速度控制步骤, 并分析了影响反应温度的可能因素.