Carbon nanoparticles from corn stalk soot and its novel application as stationary phase of hydrophilic interaction chromatography and per aqueous liquid chromatography

Carbon nanoparticles (CNPs) (6–18 nm in size) were prepared by refluxing corn stalk soot in nitric acid. The obtained acid-oxidized CNPs are soluble in water due to the existence of carboxylic and hydroxyl groups. ¹³C NMR measurement shows the CNPs are mainly of sp² and sp³ carbon structure different from CNPs obtained from candle soot and natural gas soot. Furthermore, these CNPs exhibit unique photoluminescence properties. Interestingly, the CNPs might be exploited to immobilize on the surface of porous silica particles as chromatographic stationary phase. The resultant packing material was evaluated by high-performance liquid chromatography, indicating that the new stationary phase could be used in hydrophilic interaction liquid chromatography (HILIC) and per aqueous liquid chromatography (PALC) modes. The separation of five nucleosides, four sulfa compounds and safflower injection was achieved by using the new column in the HILIC and PALC modes, respectively.     

选择性膜电极研究表面活性剂与大分子的相互作用

结合本实验室的工作介绍了表面活性剂选择性膜电极研究表面活性剂与大分子相互作用的实验装置和原理,并综述了表面活性剂选择性膜电极在研究离子型表面活性剂及其二元混合体系与不同类型大分子之间相互作用中的应用.讨论了大分子的分子量、外加盐和表面活性剂的结构对表面活性剂和大分子之间相互作用的影响结果.     

基于Eu-TTA配合物的光波长转换薄膜的制备

选用甲基苯骈三氮唑(TTA)作为Eu3+络合物的第一配体,探究了在乙醇溶液体系与水溶液体系两个不同条件下,第二配体及表面活性剂对体系荧光强度的影响。两个体系分别选择了三乙胺、邻菲咯啉(phen)作为第二配体,邻非咯啉(phen)、曲拉通-100(TX-100)作为表面活性剂,在乙醇体系下,Eu3+:TTA:三乙胺:phen的最佳比例为1:3:10:1,在水溶液体系下,Eu3+:TTA:phen:TX-100的最佳比例为1:5:1:5,最后分别将两种络合物使用掺杂法制备了聚氯乙烯(PVC)薄膜,通过荧光光谱测试,得到的两种薄膜均可将紫外光转换为可被植物吸收利用的可见光。     

Decomposition‐Assembly of Tetraphenylethylene Nanoparticles With Uniform Size and Aggregation‐Induced Emission property

Tetraphenylethylene (TPE)‐substituted poly(allylamine hydrochloride) (PAH‐g‐TPE) is synthesized by a Schiff base reaction between PAH and TPE‐CHO. The PAH‐g‐TPE forms micelles in water at pH 6, which are further transformed into pure TPE‐CHO nanoparticles (NPs) with a diameter of ≈300 nm after incubation in a solution of low pH value. In contrast, only amorphous precipitates are obtained when TPE‐CHO methanol solution is incubated in water. The aggregation‐induced emission feature of the TPE molecule is completely retained in the TPE NPs, which can be internalized into cells and show blue fluorescence. Formation mechanism of the TPE NPs is proposed by taking into account the guidance effect of linear and charged PAH molecules, and the propeller‐stacking manner between the TPE‐CHO molecules.     

三核铜(I/II)配合物[Cu(en)2][Cu(pht)2]2的合成、晶体结构及与DNA相互作用的研究

报道了多核铜配合物[Cu(en)2]•[Cu(pht)2]2 (Hpht: 苯妥英, 即5,5-二苯基-2,2-咪唑烷酮; en: 乙二胺)的溶剂热合成、晶体结构及其与DNA的相互作用. 该晶体属三斜晶系, Pī空间群, 晶胞参数: a＝0.8453(2) nm, b＝1.1878(3) nm, c＝1.5674(4) nm, α＝101.197(3)°, β＝97.690(3)°, γ＝103.283(3)°, V＝1.476(6) nm 3, Dc＝1.480 g/cm3, Z＝1, F(000)＝679, µ＝1.139 mm－1, R1＝0.0402, wR2＝0.0962[I＞2σ(I)], GOF＝1.035. XPS和X射线单晶衍射数据显示该配合物分子由混价铜组成, 包括两个一价铜和一个二价铜, 其中每个Cu(I)分别与两个苯妥英配体提供的氮原子配位, N—Cu(I)—N的夹角为177°, 一个Cu(II)与六个配位原子配位(CuN4O2), 形成一个稍变形八面体结构. 配合物与DNA相互作用研究表明, 该配合物主要是以插入方式与小牛胸腺DNA结合.     

3-哌啶甲酸及其衍生物的合成与应用研究进展

3-哌啶甲酸及其衍生物是重要的药物中间体, 具有很高的生物活性. 综述了3-哌啶甲酸及其羧基酯化、不饱和、不同位置取代与多取代衍生物的合成方法, 并对3-哌啶甲酸及其衍生物在合成γ-氨基丁酸(GABA)摄入抑制剂、抗肿瘤药、生长激素促分泌素、消炎药物、心血管药物、促智药物、抗流感病毒、骨疾病等药物中的应用进行了概述.     

QSPR study for the prediction of half-wave potentials of benzoxazines by heuristic method and radial basis function neural network

The half-wave potential (E_1/2) is an important electrochemical property of organic compounds. In this work, a quantitative structure-property relationship (QSPR) analysis has been conducted on the half-wave reduction potential (E_1/2) of 40 substituted benzoxazines by means of both a heuristic method (HM) and a non-linear radial basis function neural network (RBFNN) modeling method. The statistical parameters provided by the HM model (R² =0.946; F=152.576; RMSCV=0.0141) and the RBFNN model (R²=0.982; F=1034.171 and RMS =0.0209) indicated satisfactory stability and predictive ability. The obtained models showed that benzoxazines with larger Min valency of a S atom (MVSA), lower Relative number of H atom (RNHA) and Min n-n repulsion for a C-H bond (MnnRCHB) and Minimal Electrophilic Reactivity Index for a C atom (MERICA) can be more easily reduced. This QSPR approach can contribute to a better understanding of structural factors of the organic compounds that contribute to the E_1/2, and can be useful in predicting the E_1/2 of other compounds.      

Microwave-assisted extraction combined with gel permeation chromatography and silica gel cleanup followed by gas chromatography–mass spectrometry for the determination of organophosphorus flame retardants and plasticizers in biological samples

An analytical method for the determination of 14 organophosphorus flame retardants (OPFRs), including halogenated OPFRs, non-halogenated OPFRs and triphenyl phosphine oxide (TPPO) in biological samples was developed using gas chromatography–mass spectrometry (GC/MS). Biological samples were extracted using microwave-assisted extraction (MAE) with hexane/acetone (1:1, v/v) as the solvent; then, a two-step clean-up technique, gel permeation chromatography (GPC) combined with solid phase extraction (SPE), was carried out before GC/MS analysis. Experimental results showed that the developed method efficiently removed the lipid compounds and co-extract interferences. Moreover, using the relatively “narrow” column (with an i.d. of 10 mm) significantly decreased the elution volume and, therefore, prevented the loss of the most volatile OPFRs, especially trimethyl phosphate (TMP) and triethyl phosphate (TEP). The method detection limits (MDLs) for OPFRs in the biological samples ranged from 0.006 to 0.021 ng g⁻¹ lw, and the recoveries were in the range of 70.3–111%, except for TMP (38.9–55.6%), with relative standard deviations (RSDs) of less than 14.1%. The developed method was applied to determine the amount of the target OPFRs in biological samples (i.e., fish and domestic birds) that were collected from the Pearl River Delta (PRD) region in southern China. Of the 14 OPFRs, tri-n-butyl phosphate (TnBP), tris(2-chloroethyl) phosphate (TCEP), tris(chloropropyl) phosphate (TCPP) and tributoxyethyl phosphate (TBEP) were present in all of the biological samples that were analyzed, and dominated by TnBP, TCEP and TBEP. The concentrations of OPFRs in the biological samples that were collected from the PRD region were higher than those reported in other locations.     

The Three‐Dimensional Dendrite‐Free Zinc Anode on a Copper Mesh with a Zinc‐Oriented Polyacrylamide Electrolyte Additive

Rechargeable aqueous zinc‐ion batteries have been considered as a promising candidate for next‐generation batteries. However, the formation of zinc dendrites are the most severe problems limiting their practical applications. To develop stable zinc metal anodes, a synergistic method is presented that combines the Cu‐Zn solid solution interface on a copper mesh skeleton with good zinc affinity and a polyacrylamide electrolyte additive to modify the zinc anode, which can greatly reduce the overpotential of the zinc nucleation and increase the stability of zinc deposition. The as‐prepared zinc anodes show a dendrite‐free plating/stripping behavior over a wide range of current densities. The symmetric cell using this dendrite‐free anode can be cycled for more than 280 h with a very low voltage hysteresis (93.1 mV) at a discharge depth of 80 %. The high capacity retention and low polarization are also realized in Zn/MnO₂ full cells.     

富氧条件下氮氧化物的选择性催化还原Ⅰ．Ag／Al2O3催化剂上C3H6选择性催化还原NO的性能

 利用自行研制的全自动催化剂活性评价装置和原位漫反射红外光谱仪，分别考察了Ag的负载量和形态、氧浓度及水蒸气添加对Ag／Al2O3催化剂上C3H6选择性催化还原NO性能的影响．结果表明，Ag的最佳负载量为4％～6％，此时粒径为15nm左右的银簇粒子均匀地分散在Al2O3载体表面．在GHSV＝50000h－1和θ＝430～550℃条件下，4％Ag／Al2O3上NO转化率可达90％以上．反应过程中有机含氮化合物及NO2的生成，导致NO和NOx转化率间产生差异．当氧浓度为7％时，催化剂对NO选择性还原的催化活性最高．水的添加阻碍了活性中间物种NCO及其前驱体的形成，导致催化剂的平均活性下降．