AR-Ag(Ⅰ)体系的共振散射光谱法测定痕量银

在pH=4.4的NaAc-HAc缓冲介质和2.0×10-3mol/L十二烷基苯磺酸钠(SDBS)溶液中,Ag(Ⅰ)与茜素红(AR)可形成较稳定的离子缔合物微粒,其在324、360和500nm处分别产生3个较强的共振散射峰.在最佳实验条件下,浓度在0.022～2.160μg/mL之间的Ag(Ⅰ)与共振散射强度△I324nm呈较好的线性关系,检测限为0.139 ng/mL.据此,建立了一种测定痕量银的共振散射新方法,并将该方法用于废胶片中痕量银的测定.     

The application of digital image recognition to the analysis of two-dimensional fingerprints

High-performance liquid chromatography (HPLC) fingerprint has been commonly used in the quality control and assessment of herbal medicines, and two-dimensional (2D) fingerprint obtained by means of HPLC-diode array detector (HPLC/DAD) can provide higher reliability. In this paper, an approach to the analysis of the 2D HPLC/DAD fingerprints, which was based on digital image recognition techniques, was developed for the first time. First, wavelet transform was employed to eliminate noise signal in the 2D fingerprint, and then the 2D fingerprint was converted into grayscale image. Second, several features of the image were calculated, and hierarchical clustering. This approach was applied to the qualitative analysis of the different samples of coptis chinensis, and the clustering result of samples was all highly consistent with the real situation. Based on the densities in grayscale image, three components in standard samples were quantitative analyzed, and the obtained correlation coefficients between concentration and grayscale density were more than 0.999. Our study indicated that the analysis of the 2D HPLC/DAD fingerprint was successful based on the idea and techniques of digital image recognition techniques, and this proposed approach provided a new pathway for the analysis of two-dimensional spectrums.     

影响SAPO－11分子筛焙烧前后晶胞空间群变化的因素

 从合成参数出发，详细考察了不同因素对SAPO－11分子筛焙烧前后晶胞空间群变化的影响．发现成胶方式、成胶温度、模板剂组成、晶化温度、晶化时间及分子筛产物组成均是影响分子筛晶胞空间群变化的因素．MAS－NMR分析结果表明，分子筛的微观结构决定了分子筛晶胞空间群的变化，Si（4Si）区增加，分子筛保持为Icm2空间群的趋势增强．     

光纤生物传感器用于核酸的特异性检测

为了利用光纤传感器实现对细菌核酸分子的特异性和相对快速检测，我们使用直径1mm的石英光纤和635nm激光二极管，利用倏逝波原理制作了光纤生物传感器。光纤经过处理后产生醛基化基团，然后与核酸分子进行共价结合。通过3个实验来验证传感器的特异性和灵敏度。蒌光素溶液直接检测，使用互补模式寡核苷酸分子（25mer)进行核酸杂交模式实验和设计嗜肺军团菌一段特异性探针一 光标记嗜肺军团菌染色体DNA杂交。结果表明：光纤检测荧光素的灵敏度可达0.01mmol/L，而生物芯片扫描仪最低可检测到1nmol/L的荧光素；模式寡 核苷酸杂交表明：光纤传感器可以特异地检出目的核酸分子，灵敏度可达纳克级水平；染色体杂交结果显示在正常检测浓度下，光纤检测军团菌之信噪比达到了6：1，同时具有较好的特异性。检测时间约需要3－4h。我们构建的光纤生物传感器可以用于核酸分子的特异性检测，并且具有较好的灵敏度，对光纤表面修饰、样品处理和杂交过程的优化可望使之应用于实际标本的检测。     

毛细管电泳法快速测定复方地芬诺酯片中的地芬诺酯和阿托品

建立了毛细管电泳高频电导法同时测定地芬诺酯和阿托品的方法。探讨了缓冲溶液、有机溶剂添加剂、分离电压和进样条件以及毛细管内径和长度等因素对分离检测的影响。在电泳介质为10.0mmol/L乳酸-15.0?H5OH、分离电压20.0kV的优化条件下,6min内即可实现地芬诺酯和阿托品的同时分离检测,线性范围分别为5.00~500和2.00~320mg/L;检出限分别为3.0和1.0mg/L。     

Graphene-Oxide-Based Fluoro- and Chromo-Genic Materials and Their Applications

Composite materials and their applications constitute a hot field of research nowadays due to the fact that they comprise a combination of the unique properties of each component of which they consist. Very often, they exhibit better performance and properties compared to their combined building blocks. Graphene oxide (GO), as the most widely used derivative of graphene, has attracted widespread attention because of its excellent properties. Abundant oxygen-containing functional groups on GO can provide various reactive sites for chemical modification or functionalization of GO, which in turn can be used to develop novel GO-based composites. This review outlines the most recent advances in the field of novel dyes and pigments encompassing GO as a key ingredient or as an important cofactor. The interactions of graphene with other materials/compounds are highlighted. The special structure and unique properties of GO have a great effect on the performance of fabricated hybrid dyes and pigments by enhancing the color performance of dyes, the anticorrosion properties of pigments, the viscosity and rheology of inks, etc., which further expands the applications of dyes and pigments in dyeing, optical elements, solar-thermal energy storage, sensing, coatings, and microelectronics devices. Finally, challenges in the current development as well as the future prospects of GO-based dyes and pigments are also discussed. This review provides a reference for the further exploration of novel dyes and pigments.     

Transport properties and magnetoresistance in La0.8Te0.2MnO3/ZrO2 composites

The transport properties and magnetoresistance of electron-doped manganate / insulator composites (La_0.8Te_0.2MnO₃)_{1 - x}/(ZrO₂)_x (x=0, 0.3, and 0.5) are investigated. It is found that the metal-insulator transition temperature of this system shifts to a lower value as the ZrO₂ content increases. The introduction of ZrO₂ enhances both the domain scattering and electron relative scattering in the metal transport region. In the adiabatic small polaron hopping transport region, the thermal activation energy seems invariable regardless of the ZrO₂ content. The application of a magnetic field promotes the charge transportation capabilities of the composites, and the magnetoresistance is enhanced with an increase of the ZrO₂ content. This could be attributed to the more remarkable modification effect of magnetic field on ordering degree in the composites than in pure La_0.8Te_0.2MnO₃.     

Red top-emitting organic light-emitting device with improved efficiency and saturated color

In this work, characteristics of microcavity top-emitting red organic light-emitting device (TEROLED) having metallic electrodes had been examined. The TEOLED shows the higher efficiency in comparison with that of the bottom OLED. However, color variation with the increasing view angles is also observed. For the purpose of diminishing the blue-shift of resonant wavelength (RW) in the device with increasing view angle, the effect of out-coupling layer on the emission properties of the TEOLED is discussed in detail. Finally, the out-coupling layer was introduced in theory without sacrificing the efficiency through precise optical simulation.     

介质部分填充平行平板传输线微放电过程分析

本文主要研究了介质填充微波部件微放电随时间演变的过程,重点分析了介质微波部件微放电自熄灭机理.以介质部分填充平行平板传输线为研究对象,忽略空间电荷效应,采用自主研发粒子模拟软件模拟微放电过程,并将模拟结果与金属微波部件结果进行对比.结果表明,在一定功率下,金属微放电过程中电子数目呈指数形式增长,而介质微放电过程经历初始电子倍增后发生自熄灭现象,同时发现在电子数目即将下降为0时,介质表面的平均二次电子发射系数大于1或约等于1.另外,在上述模拟结果的基础上对微放电过程中介质表面积累电荷问题进一步分析,模拟结果表明,如果持续向微波部件内注入电子,介质表面的平均二次电子发射系数最终都约等于1.所得结论对研究复杂介质填充微波部件微放电的机理具有一定的理论指导价值.     

Growth of SnO2 nanoparticles via thermal evaporation method

Tin oxide (SnO₂) nanoparticles were fabricated by evaporation of Sn powers at 1000 °C in air pressure. The as-deposited SnO₂ particles were single crystal structure, which were mostly spherical shape, the diameter of particles was ranging from 200 to 600 nm. The photoluminescence (PL) spectrum showed that a sharp emission peak at around 393 nm with the excitation wavelength at 325 nm, which suggested possible applications in nanoscaled optoelectronic devices. It was also found that the holding time affects the morphology of the products. The formation mechanism of SnO₂ particles was discussed.