应用化学发光法研究大豆分离蛋白水解物的抗氧化活性

本文研究了枯草芽孢杆菌固体中性蛋白酶水解大豆分离蛋白的作用条件，应用化学发光法测定不同水解条件的产物清除超氧阴离子能力的大小，并以此确定水解的工艺条件。结果表明，大豆蛋白水解物清除超氧阴离子的能力并不是与水解度正相关。     

Synthesis of ionic liquids based on alkylimidazolium salts and their coal dissolution and dispersion properties

A series of new bis (imidazolium) cation-based ionic liquids, wherein two imidazole rings are tethered by alkyl ether chains (oxygen numbers) of different lengths, were prepared, and their coal dissolution and dispersion properties were studied. It was found these ionic liquids can be used to fragment, disperse, and partially dissolve micrometer-size coal particles by simply mixing ionic liquid/coal dispersions. Dissolution performances and light hydrocarbon production were found to be sensitively increased by increasing the lengths of alkyl ether chains between imidazolium rings.     

Tens of micron-sized unilamellar nanosheets of Y/Eu layered rare-earth hydroxide: efficient exfoliation via fast anion exchange and their self-assembly into oriented oxide film with enhanced photoluminescence

Layered rare-earth hydroxide (LRH) crystals of (Y_0.95Eu_0.05)₂(OH)₅NO₃·nH₂O with a lateral size of ∼ 300 μm and a thickness of ∼ 9 μm have been synthesized via a hydrothermal reaction of mixed nitrate solutions in the presence of mineralizer NH₄NO₃ at 200 °C for 24 h. LRH exhibits the ability to undergo intercalation and anion exchange with DS⁻ (C₁₂H₂₅OSO₃⁻) via hydrothermal treatment. Compared with traditional anion exchange at room temperature, hydrothermal processing not only shortens the anion exchange time from 720 to 24 h but also increases the basal spacing. The arrangements of DS⁻ in the interlayer of LRH are significantly affected by the DS⁻ concentration and reaction temperature, and the basal spacing of the LRH-DS sample in the crystal edge is assumed to be larger than that in the crystal center. A higher DS⁻ concentration and reaction temperature both induce more intercalation of DS⁻ anions into the interlayer gallery, thus yielding a larger basal spacing. Unilamellar nanosheets with a lateral size of ≽60 μm and a thickness of ∼ 1.6 nm can be obtained by delaminating LRH-DS in formamide. The resultant unilamellar nanosheets are single crystalline. Transparent (Y_0.95Eu_0.05)₂O₃ phosphor films with a uniform [111] orientation and a layer thickness of ∼ 90 nm were constructed with the nanosheets as building blocks via spin-coating, followed by proper annealing. The oriented oxide film exhibits a strong red emission at 614 nm (the ⁵D₀–⁷F₂ transition of Eu³⁺), whose intensity is ∼ 2 times that of the powder form owing to the significant exposure of the (222) facets.     

Fabrication of capped gold nanoparticles by using various amino acids

The production of gold nanoparticles (GNPs) by amino acid is one of the most attractive and interesting subjects in nanobiotechnology. In this study, amino acids have been utilised as a reducing agent and also an agent for capping GNPs. The GNPs were prepared using a reduction solution containing gold cations with optimum concentration of gold salt (5?mM), and also functionalised by glutamic acid, phenylalanine and tryptophan with optimum concentration of amino acids (25?mM). The optimum condition of gold solution and amino acids were achieved by ultraviolet–visible spectroscopy. The size of nanoparticles was obtained 5–20, 10–20 and 20–30?nm, respectively, by transmission electron microscopy and dynamic light scattering techniques. The results obtained from experimental and quantum calculations confirm that amino acids have strong bond while they have anion binding. Moreover, the free carboxylic groups of capped GNPs are one of the suitable and capable beads for binding biological agents. As a result, the medical applications of amino acids and proteins can be used as a practical method due to the strong interaction of peripheral amine groups with nanoparticles.     

Anodic Electrochromism for Energy‐Efficient Windows: Cation/Anion‐Based Surface Processes and Effects of Crystal Facets in Nickel Oxide Thin Films

Anodic electrochromic (EC) oxides are of major interest as counter electrodes for smart window applications owing to their unique optical properties upon charge insertion and extraction. However, performance optimization of such oxides has been hampered by limited understanding of their EC mechanism, particularly in Li⁺‐conducting electrolytes. This paper reports on NiO_x films with 1.16 ≤ x ≤ 1.32, prepared by sputter deposition. These films are immersed in an electrolyte of lithium perchlorate in propylene carbonate, and EC properties are studied by cyclic voltammetry and in situ optical transmittance measurements. The electrochromism is significantly enhanced at large values of x. It has been found that charge exchange in Ni oxide is mainly due to surface processes and involves both cations and anions from the electrolyte, which is different from the case of cathodic EC materials such as WO₃. Whereas previous studies of Ni oxide have focused on cation intercalation, the cation/anion‐based mechanism presented here offers a new paradigm for designing and developing EC devices such as smart windows for energy efficient buildings.     

功能分子材料为受体的阴离子识别研究新进展

超分子化学领域最近的热点和焦点问题之一是阴离子识别的主客体化学及其应用研究。在自然界或生命过程,人工系统及材料科学中,阴离子识别往往也起着至关重要的作用。近年来,关于阴离子识别的研究取得了令人鼓舞的进展。就新颖功能有机小分子阴离子识别、阳离子增强的阴离子识别、卤键与氢键协同阴离子识别和阴离子识别受体的大分子化等几个阴离子识别研究的新动向予以扼要综述。     

Clean hydrogen for mobility – Quo vadis?

Achieving complete combustion of fossil fuels has long been thought of as a sufficient remedy for tackling vehicular emissions and the ensuing environmental effects. However, thanks to the increasing awareness around the climate change, the global dialogue has now shifted to realizing a carbon-free economy, which has set stricter curbs on the energy source that can power the future mobility. Therefore, the idea of “clean combustion” requires rethinking. Of the many choices for alternative clean fuels that are both energy-efficient and environment-friendly, hydrogen has always been eyed as the best clean alternative there is. This article reviews various available approaches to utilizing hydrogen for mobility applications with a discussion of their relative merits and shortcomings. In addition to well-discussed methods like fuel cell electric vehicles, hydrogen-based IC engines, and dual-fuel operation with hydrogen, this review also assesses the technical and economic feasibilities of using hydrogen in e-fuels and their implications for our existing infrastructure and future energy demands.     

阴离子原位聚合碳纤维增强尼龙6界面的研究

碳纤维表面可接枝上高聚物活性官能团,以调节复合材料中纤维与树脂之间的界面效应,从而改善复合材料的性能,通过控制接枝高聚物的结构可以很好的设计具有预定性能的界面层。热处理对纤维的强度不会造成影响,其表面官能团含量在1h附近达到最大值。未经异氰酸酯接枝处理的碳纤维表面没有聚合接枝尼龙大分子,热处理后再经过异氰酸酯处理,能明显看到尼龙分子接枝到纤维表面。当聚合单体中不添加活化剂,纤维表面的树脂接枝率可达到18.8%;单体中添加0.003的活化剂(占单体摩尔比),碳纤维表面的尼龙6接枝率只有7.65%,这是单体基体与纤维界面反应竞争的结果。碳纤维表面对原位聚合生成的尼龙以及改性尼龙结晶有很大影响,碳纤维未接枝处理时表面形成的横晶比较少;碳纤维接枝处理后可以看见纤维附近存在大量晶体结构,结晶体密度高,有利于材料性能改良。