Discrimination of Thermoplastic Polyesters by MALDI-TOF MS and Py-GC/MS

The aim of this work is to discriminate thermoplastic polyester-polyethylene terephthalate (PET), polybutylene terephthalate (PBT), and polytrimethylene terephthalate (PTT), which cannot be easily identified by many methods. Both matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) and pyrolysis gas chromatography/mass spectrometry (Py-GC/MS) were applied to identify these polyesters owing to their analytical ability to determining polymers' chemical structure. The three thermoplastic polyesters can be easily distinguished by MALDI-TOF MS according to their different repeated units. Py-GC/MS was used to analyze their specific pyrolyzates. The three polyesters can be identified through their characteristic pyrolysis products as well.     

Ordered Mesoporous Carbon and Thiolated Polyaniline Modified Electrode for Simultaneous Determination of Cadmium(II) and Lead(II) by Anodic Stripping Voltammetry

The fabrication and evaluation of a glassy carbon electrode (GCE) modified with ordered mesoporous carbon (OMC), 2‐mercaptoethanesulfonate (MES)‐tethered polyaniline (PANI) and bismuth for simultaneous determination of trace Cd²⁺ and Pb²⁺ by differential pulse anodic stripping voltammetry (DPASV) are presented here. The morphology and electrochemical properties of the fabricated electrode were respectively characterized by scanning electron microscopy (SEM) and electrochemical impedance spectroscopy (EIS). Experimental parameters such as PANI disposition, preconcentration potential, preconcentration time and bismuth concentration were optimized. Under optimum conditions, the fabricated electrode exhibited linear calibration curves ranged from 1 to 120 nM for Cd²⁺ and Pb²⁺. The limits of detection (LOD) were 0.26 nM for Cd²⁺ and 0.16 nM for Pb²⁺ (S/N=3), respectively. Additionally, repeatability, reproducibility, interference and application were also investigated, and the proposed electrode exhibited excellent performance. The proposed method could be extended for the development of other new sensors for heavy metal determination.     

萘酰亚胺类荧光分子探针的研究进展

荧光分子探针作为一种有效的金属离子检测手段,不仅使用方便,而且具有高灵敏度,高选择性等突出的优点.作者综述了萘酰亚胺类荧光分子探针的最新研究进展;指出萘酰亚胺化合物具有独特的荧光化学性质(如荧光量子产率高、荧光发射波长适中、斯托克斯位移大、光稳定性好、结构易于修饰等),因此被广泛应用于荧光探针研究领域,并且在合成、离子识别、检测及细胞成像等方面不断取得新的应用.     

质量控制图用于石墨炉原子吸收光谱法检测海水中铅元素

为保证海水中重金属检测结果的准确可靠,以铅元素为例,每个工作日使用石墨炉原子吸收光谱仪平行测定铅质控样2次,收集20组有效数据后,通过计算均值、标准差得出上下控制限、警告线及辅助限,绘制出在当前实验室环境条件、仪器设备、试剂药品和人员水平等因素条件下的质量控制图。该质量控制图不仅用于实际检测过程中对检测结果进行监控,还可为该实验室的人员考核、留样复测等实验室质量控制行为提供结果判定依据。     

Synthesis and Characterizations of Strongly Phosphorescent Copper(I) Halide Complexes with Bridged Bis[2-(diphenylphosphino)phenyl]ether Ligand

A series of strongly phosphorescent copper(I) halide complexes, namely [Cu(μ-X)POP]₂ (X = Cl (1), Br (2), I (3), Br_0.5Cl_0.5 (4), POP = bis[2-(diphenylphosphino)phenyl]ether), have been synthesized by reacting CuX with the diphosphine ligand in 1:1 molar ratio. All complexes were characterized by spectroscopic analysis (IR, UV–Vis), elemental analysis, and photoluminescence study. Single-crystal X-ray diffraction revealed that complex 2 is a dinuclear structure which is constructed by two μ-X bridges and two POP ligands as μ₂ bridges. Other complexes were determined as isologues of complex 2 by powder X-ray diffraction and elemental analysis. All complexes exhibit intense blue-green phosphorescence with a lifetime of ~1 μs in the solid state. The halogen-mixed complex presents a lightly change in the luminescence comparing to that of parent complexes. The excited states of all complexes have been assigned as halide-to-ligand charge transfer state mixed metal-to-ligand charge transfer character based on the time-dependent density functional theory calculations. All complexes are thermally stable according to thermogravimetric analysis so that they are suitable for applying in luminescent devices.     

Faddeev-Jackiw and the improved methods in quantization of the superconductive system

In this paper, we give the overview on Faddeev-Jackiw method and its improved one, as well as the relative studies recently and realize quantization of the superconductive system by the two methods, we get the same results by the two disposal methods. Furthermore, at convenience of the familiar study in this system, we take it as the application example and compare the two methods by dealing with this system from different aspects, demonstrate the improved Faddeev-Jackiw method is effective and significative, and represent the superiorities of the improved Faddeev-Jackiw method. We show that the improved method may simplify investigations of different complicated constrained systems.     

Flexible conducting polymer transistors with supercapacitor function

Planar organic electrochemical transistors (OECTs) using PEDOT:PSS as the channel material and nanostructured carbon (nsC) as the gate electrode material and poly(sodium 4‐styrenesulfonate (PSSNa) gel as the electrolyte were fabricated on flexible polyethylene terephthalate (Mylar^®) substrates. The nsC was deposited at room‐temperature by supersonic cluster beam deposition (SCBD). Interestingly, the OECT acts as a hybrid supercapacitor (to give a device that we indicate as transcap). The energy storage ability of transcaps has been studied with two cell configurations: one featuring PEDOT:PSS as the positive electrode and nsC as the negative electrode and another configuration with reversed electrode polarity. Potentiostatic charge/discharge studies show that both supercapacitors show good performance in terms of voltage retention, in particular, when PEDOT:PSS is used as the positive electrode. Galvanostatic charge–discharge characteristics show typical symmetric triangular shape, indicating a nearly ideal capacitive behavior with a high columbic efficiency (close to 100%). © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017 , 55, 96–103     

Patterning of triblock copolymer film and its application for surface-enhanced Raman scattering

In this paper,microphase behavior of an ABC triblock copolymer,polystyrene-block-poly(2-vinylpyridine)-block-poly(ethylene oxide),namely PS-b-P2VP-b-PEO,was systematically studied during spin-coating and solvent vapor annealing based on various parameters,including the types of the solvent,spin speed and thickness.The morphological features and the microdomain location of the different blocks were characterized by atomic force microscope (AFM) and high resolution transmission electron microscopy (HRTEM).With increasing thickness,the order-order transition from nanopores array to the pattern of nanostripes was observed due to microdomain coarsening.These processes of pattern transformation were based on the selectivity of toluene for different blocks and on the contact time between solvent molecules and the three blocks.This work provides different templates for preparation of gold nanoparticle array on silicon wafer,which can be adopted as an active surface-enhanced Raman scattering (SERS) substrate for poly(3-hexylthiophene) (P3HT).