Electrochemiluminescence Detection of TNT by Resonance Energy Transfer through the Formation of a TNT–Amine Complex

2,4,6‐Trinitrotoluene (TNT) is a widely used nitroaromatic explosive with significant detrimental effects on the environment and human health. Its detection is of great importance. In this study, both electrochemiluminescence (ECL)‐based detection of TNT through the formation of a TNT–amine complex and the detection of TNT through electrochemiluminescence resonance energy transfer (ECRET) are developed for the first time. 3‐Aminopropyltriethoxysilane (APTES)‐modified [Ru(phen)₃]²⁺ (phen=1,10‐phenanthroline)‐doped silica nanoparticles (RuSiNPs) with uniform sizes of (73±3) nm were synthesized. TNT can interact with APTES‐modified RuSiNPs through charge transfer from electron‐rich amines in the RuSiNPs to the electron‐deficient aromatic ring of TNT to form a red TNT–amine complex. The absorption spectrum of this complex overlaps with the ECL spectrum of the APTES‐modified RuSiNPs/triethylamine system. As a result, ECL signals of the APTES‐modified RuSiNPs/triethylamine system are turned off in the presence of TNT owing to resonance energy transfer from electrochemically excited RuSiNPs to the TNT–amine complex. This ECRET method has been successfully applied for the sensitive determination of TNT with a linear range from 1×10^?9 to 1×10^?6 M with a fast response time within 1 min. The limit of detection is 0.3 nM . The method exhibits good selectivity towards 2,4‐dinitrotoluene, p‐nitrotoluene, nitrobenzene, phenol, p‐quinone, 8‐hydroxyquinoline, p‐phenylenediamine, K₃[Fe(CN)₆], Fe³⁺, NO₃^?, NO₂^?, Cr³⁺, Fe²⁺, Pb²⁺, SO₃^2?, formaldehyde, oxalate, proline, and glycine.     

Co-Intercalation of Dual Charge Carriers in Metal-Ion-Confining Layered Vanadium Oxide Nanobelts for Aqueous Zinc-Ion Batteries

Vanadium-based oxides with high theoretical specific capacities and open crystal structures are promising cathodes for aqueous zinc-ion batteries (AZIBs). In this work, the confined synthesis can insert metal ions into the interlayer spacing of layered vanadium oxide nanobelts without changing the original morphology. Furthermore, we obtain a series of nanomaterials based on metal-confined nanobelts, and describe the effect of interlayer spacing on the electrochemical performance. The electrochemical properties of the obtained Al_2.65V₆O₁₃ ⋅ 2.07H₂O as cathodes for AZIBs are remarkably improved with a high initial capacity of 571.7 mAh ⋅ g⁻¹ at 1.0 A g⁻¹. Even at a high current density of 5.0 A g⁻¹, the initial capacity can still reach 205.7 mAh g⁻¹, with a high capacity retention of 89.2 % after 2000 cycles. This study demonstrates that nanobelts confined with metal ions can significantly improve energy storage applications, revealing new avenues for enhancing the electrochemical performance of AZIBs.     

GaAs极化电子源激活的yo-yo过程研究

通过对GaAs晶体产生极化电子束流的实验过程研究，着重对yo-yo过程中不同的实验参数对产生极化束流以及束流稳定情况的影响进行了分析，为获得稳定而持久的极化电流提供了有力的实验支持，并讨论了极化电流强度的可控性.     

基于胆甾相液晶的可调制光子晶体

将胆甾相液晶填充进胶体晶体内部空隙, 通过胆甾相液晶与胶体晶体的耦合, 构建了一种新型可调制液晶光子晶体. 填充于胶体晶体内部的胆甾相液晶织构呈现典型的手性近晶相(S)特征. 由于胆甾相液晶具有特定的选择性反射, 当胶体晶体的带隙处于胆甾相液晶的反射波长范围之内, 则随着温度的改变, 胶体晶体的带隙与胆甾相液晶的带隙同时发生蓝移. 在一定温度条件下, 胆甾相液晶的带隙将与胶体晶体的带隙发生耦合, 实现了光子晶体带隙在单峰与双峰之间的可逆切换.     

A sensitive and selective LC‐MS/MS method for the quantitative determination of segetalin A from the plasma of rats

A sensitive and selective LC‐MS/MS method was developed and validated for the determination and pharmacokinetic investigation of segetalin A in rat plasma. Sample preparation was accomplished through a simple SPE procedure for the removal and preconcentration of the analyte and IS. Plasma samples were separated by HPLC on a Symmetry C₁₈ column using a mobile phase consisting of methanol and 0.1% formic acid in water (70:30, v/v) with isocratic elution. The quantification was performed using multiple reaction monitoring with the transitions m/z 610.3 → 511.2 for segetalin A and m/z 779.4 → 751.4 for IS, respectively. The calibration curve was linear over the range of 8.0–4000 ng/mL with a limit of quantitation (LOQ) of 8.0 ng/mL. This method was applied in a pharmacokinetic study of segetalin A in rats. For intravenous (i.v.) administration, the plasma concentrations of segetalin A decreased quickly (t_1/2z, 1.31 ± 0.341 h). For oral administration, the plasma concentrations of segetalin A increased to a peak value at 1.50 ± 0.577 h, followed by a gradual decrease to the LOQ in 12 h. The mean AUC values after i.v. and oral administration were 553 ± 105 and 1482 ± 110 ng h/mL, respectively. Copyright © 2015 John Wiley & Sons, Ltd.