The synthesis of 1,2-diarylindenes via DDQ-mediated dehydrogenative intramolecular cyclization

A direct DDQ-mediated dehydrogenative intramolecular cyclization of (Z)-1,2,3-triaryl substituted propylenes promoted by Cu(OAc)₂ was developed, providing 1,2-diarylindene derivatives in moderate to good yields (up to 92%) under mild conditions. This protocol provides a straightforward access to 1,2-diarylindenes via DDQ-mediated benzylic/allylic sp³ C–H bond activation.     

Further revisions on the diterpenoid alkaloids reported in a JNP paper (2012, 75, 1145–1159)

We have corrected (Tetrahedron2013, 69, 5859–5866) the structures of diterpenoid alkaloids reported in the Journal of Natural Products2012, 75, 1145–1159. Our follow-up experiments compel us to present further revisions and clarifications on the diterpenoid alkaloids:     

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.     

Chiral Monolithic Absorbent Constructed by Optically Active Helical‐Substituted Polyacetylene and Graphene Oxide: Preparation and Chiral Absorption Capacity

Chiral monolithic absorbent is successfully constructed for the first time by using optically active helical‐substituted polyacetylene and graphene oxide (GO). The preparative strategy is facile and straightforward, in which chiral‐substituted acetylene monomer (Ma), cross‐linker (Mb), and alkynylated GO (Mc) undergo copolymerization to form the desired monolithic absorbent in quantitative yield. The resulting monoliths are characterized by circular dichroism, UV–vis absorption, scanning electron microscopy (SEM), FT‐IR, Raman, energy‐dispersive spectrometer (EDS), X‐ray diffraction (XRD), Brunauer–Emmett–Teller (BET), XPS, and thermogravimetric analysis (TGA) techniques. The polymer chains derived from Ma form chiral helical structures and thus provide optical activity to the monoliths, while GO sheets contribute to the formation of porous structures. The porous structure enables the monolithic absorbents to demonstrate a large swelling ratio in organic solvents, and more remarkably, the helical polymer chains provide optical activity and further enantio‐differentiating absorption ability. The present study establishes an efficient and versatile methodology for preparing novel functional materials, in particular monolithic chiral materials based on substituted polyacetylene and GO.

     

Preparation of C-Terminal Epitope Imprinted Particles Via Reversible Addition-Fragmentation Chain Transfer Polymerization and Zn2+ Chelating Strategy: Selective Recognition of Cytochrome c

Chromatographia - The C-terminal epitope imprinted polymers on the silica were prepared by reversible addition-fragmentation chain transfer (RAFT) strategy with C-terminal nonapeptide of cytochrome...     

Activation of Au–Ag Plasmonic Bimetallic Nanocatalysts with Cold Plasma: The Role of Loading Sequence of Plasmonic Metals and Discharge Atmosphere

The activation of Au–Ag plasmonic bimetallic nanocatalyst can make the nanocatalyst exhibit superior visible-light (VL) photocatalytic activity. An efficient activation of Au–Ag nanocatalyst by cold plasma requires the restructuring of Au and Ag species over catalyst surface to form Au–Ag alloy nanoparticles while suppressing agglomeration of the nanoparticles. We here report that the loading sequence of Au and Ag components on titanium dioxide (TiO₂) support during catalyst preparation and discharge atmosphere play important roles in the plasma activation. Preparation of AuAg/TiO₂ nanocatalyst by depositing Ag and Au in sequence could avoid the undesired loss of Ag component, and ensure an effective restructuring of Au and Ag species in O₂ plasma activation. Compared with the reductive (H₂) and inert (Ar and N₂) plasmas, discharge in oxidative O₂ establishes Coulomb field with the negatively charged species over catalyst surface and enable the restructuring and intimate interaction of Au and Ag species. The catalyst characterization and density functional theory calculations suggest that O₂ plasma endows AuAg/TiO₂ nanocatalyst with large numbers of Au–Ag alloy nanoparticles, small size of plasmonic nanoparticles, high density of coordinatively unsaturated sites, and high content of surface oxygen species in the activation, which facilitates the adsorption and activation of O₂, and thus CO oxidation reaction under VL irradiation.

     

基于微流控热泳的生物传感技术※

复杂生命体系中关键分子及微纳生物粒子的高灵敏、高特异检测, 对理解多层次多尺度生物学过程、阐明疾病发生发展机制和探索新型生物标志物等具有重要意义. 微流控生物传感器整合了微流控技术和生物传感技术的诸多优势, 在微量生物样本精准测量方面取得了显著进展. 近年来, 微流控热泳生物传感技术(Thermomicrofluidic biosensing)利用物质在局域温度梯度场中的热泳定向迁移现象, 并结合均相生物传感及信号放大新策略, 实现了复杂样本中生物分子及微纳生物粒子的快速、高灵敏、原位检测. 重点阐述了以热泳为核心的微流控传感技术, 包括微量热泳、热泳-对流耦合、热泳-扩散泳耦合以及热泳-电泳耦合等方法, 总结了不同传感方法的原理、特点及其在生物分子(蛋白、核酸等)与微纳生物粒子(细胞外囊泡、病毒、细胞等)检测中的应用, 并探讨了微流控热泳技术在生物医学检测领域中面临的挑战与未来发展方向.     

海水电解面临的挑战与机遇：含氯电化学中先进材料研究进展

氢气是一种清洁高效的能源载体,通过海水电解规模化制备氢气能够为应对全球能源挑战提供新的机遇。然而,缺乏高活性、高选择性和高稳定性的理想电极材料是在腐蚀性海水中连续电解过程的一个巨大挑战。为了缓解这一困境,需要从基础理论和实际应用两方面对材料进行深入研究。近年来,人们围绕电极材料的催化活性、选择性和耐腐蚀性进行了大量的探索。本文重点总结了高选择性和强耐腐蚀性材料的设计合成与作用机制。其中详细介绍了多种电极材料(如多金属氧化物、Ni/Fe/Co基复合材料、氧化锰包覆异质结构等)对氧气生成选择性的研究进展;系统论述了各种材料的抗腐蚀工程研究成果,主要讨论了本征抗腐蚀材料、外防护涂层和原位产生抗腐蚀物种三种情况。此外,提出了海水电解过程中存在的挑战和潜在的机遇。先进纳米材料的设计有望为解决海水电解中的氯化学问题提供新思路。     

Eco friendly synthesis of fluorescent carbon dots for the sensitive detection of ferric ions and cell imaging

This study established a ferric ion (Fe³⁺) detection method as a result of the fluorescence quenching effect of Fe³⁺ on carbon dots (CDs). Specifically, we proposed, a green microwave synthesis route towards fluorescent CDs that requires only the brewer’s spent grain as starting materials. Transmission electron microscopy, X-ray diffraction, Fourier-transform infrared spectra and X-ray photoelectron spectroscopy were performed to investigate the CDs characteristic: morphology, size distribution, functional groups, and composition, respectively. The experimental results, which were run under optimal experimental conditions, indicated that the fluorescence intensity and concentration of Fe³⁺ were within the desired linear range (0.3–7 μM). The detection limit of this assay towards Fe³⁺ was 95 nM. The proposed method showed significant selectivity with respect to interfering ions. We evaluated the potential application of this method with tap water, lake water and fetal bovine serum as real samples. Additionally, the CDs could be served as superior bioimaging probes in Hela cells as a result of their excellent optical stability and good biocompatibility. In a word, the present study provides a new idea for CDs derived from the waste of agricultural products for detecting food or environmental contaminants and cell imaging.