铁磁/反铁磁/铁磁三层膜系统中反铁磁自旋结构及其交换各向异性

研究铁磁/反铁磁/铁磁三层膜中界面存在二次以及双二次交换耦合下反铁磁磁矩转动及其交换各向异性.结果表明,其反铁磁膜中的磁矩转动存在可逆"恢复行为"、不可逆"连续倒转行为"以及不可逆"中断倒转行为"三种情形,三种情形的出现强烈地依赖于两界面处的线性耦合和双二次耦合.钉扎界面的交换耦合与旋转界面的交换耦合相互竞争,当钉扎界面耦合占主导时,反铁磁磁矩发生可逆"恢复行为",系统出现交换偏置.在旋转界面耦合占主导情形下,其线性耦合与双二次耦合也相互竞争,分别导致反铁磁磁矩发生不可逆"连续倒转行为"和不可逆"中断倒转行为",系统都不出现交换偏置,但矫顽场都得以增强.相关结论为实验上观测的磁滞能耗以及界面垂直耦合提供了可能的解释.     

Acetylene black paste electrode modified with molecularly imprinted polymers/graphene for the determination of bisphenol A

A novel nanocomposite of molecularly imprinted polymers and graphene sheets was fabricated and used to obtain a highly conductive acetylene black paste electrode with high conductivity for the detection of bisphenol A. The two‐dimensional structure and the chemical functionality of graphene provide an excellent surface for the enhancement of the sensitivity of the electrochemical sensor and the specificity of molecularly imprinted polymers to improve detection of bisphenol A. The synergistic effect between graphene and molecularly imprinted polymers confers the nanocomposite with superior conductivity, broadened effective surface area and outstanding electrochemical performance. Factors affecting the performance of the imprinted sensor such as molecularly imprinted polymers concentration, foster time and scan rate are discussed. The sensor successfully detects bisphenol A with a wide linear range of 3.21 × 10^?10 to 2.8 × 10^?1 g/L (R = 0.995) and a detection limit of 9.63 × 10^?11g/L. The fabricated sensor also possessed high selectivity and stability and exhibits potential for environmental detection of contaminants and food safety inspection.     

HBa(D)空间的内插定理

研究了一类由H^p空间构成的Ba空间的内插性质,给出了H^Ba(D)空间的三个内插定理。     

机械剥离石墨烯修饰电极检测食品接触材料中双酚A的迁移量

采用机械剥离石墨烯修饰电极快速检测食品接触材料中双酚A的迁移量。X射线电子衍射表征显示机械剥离石墨烯表面不存在含氧官能团,与化学还原石墨烯相比,机械剥离石墨烯对双酚A具有更好的电催化性能,降低了双酚A的氧化过电位,提高了电流响应。在优化的试验条件下,双酚A的浓度在1.0×10-7~1.5×10-5mol·L-1范围内与氧化峰电流呈线性关系,检出限(3S/N)为3.0×10-8mol·L-1。采用该电极对食品模拟物中的双酚A进行检测,加标回收率在85.1%~104%之间,测定值的相对标准偏差(n=6)在2.7%~5.9%之间。     

单核和双核钌配合物在铟锡氧化物电极上的电化学行为及对双酚A的催化氧化

本文应用循环伏安法和微分脉冲伏安法研究了两种新型单、双核多吡啶钌(Ⅱ)配合物在铟锡氧化物(ITO)电极上的电化学行为及对双酚A(BPA)的催化氧化。研究结果表明,单、双核配合物在ITO电极上均出现两个归属为中心离子和亚胺基的氧化波,双核配合物的峰电流约为单核的2倍,表现为通过桥联配体在两中心离子间的电子转移速度较其与电极间的大。同时,两种配合物对BPA的氧化呈现相近的催化氧化活性。此外,讨论了pH值对单、双核钌配合物电化学行为的影响,比较分析了它们对BPA的催化氧化过程。     

双酚A型环氧树脂多孔微球

双酚Ａ型环氧树脂多孔微球杨振忠许元泽俞浩赵得禄（中国科学院化学研究所高分子物理开放实验室北京１０００８０）关键词多孔微球，双酚Ａ环氧树脂，相反转技术微米级高分子多孔微球在生物医学、电子、印刷、信息业等方面具有重要作用．然而，通常的乳液聚合，悬浮聚合...     

The computation of non-perfect Padé-Hermite approximants

We describe a simple and efficient algorithm to generate a number of polynomial vectors which can be used to describe all possible solutions for a type I Padé-Hermite problem. If denotes the order of approximation, which is a measure for the size of the Padé-Hermite problem, it uses only order ² operations, even if the given system is not perfect. To this end, the problem is considered as a special case of a generalized Padé-Hermite problem which is also defined and analysed.     

Efficient Detection of Environmental Estrogens Bisphenol A and Estradiol By Sensing System Based on AuNP-AuNP-UCNP Triple Structure

A sensing system based on AuNP-AuNP-UCNP triple structure for efficient detection of dual targets bisphenol A and estradiol was constructed. In the preparation of triple structure, the gold nanoparticles (AuNPs) and upconversion nanoparticles (NaYF₄: Yb, Er, Gd, UCNPs) were synthesized and surface modified. Then, the two nanoparticles and their aptamers were connected to form two kinds of optical fluorescent probes. A nucleic acid sequence that matches with two aptamers was designed, rendering the probes to get close based on the principle of complementary base pairing. On the basis of this, a sensing system with triple structure was prepared, and its connecting effect was characterized by TEM. With this system, dual targets of bisphenol A and estradiol were detected efficiently and conveniently through quantitatively determination by fluorescence and UV spectrophotometer. At the reaction temperature 30 °C and pH 7.8, this method exhibited good linear range for determination of bisphenol A and estradiol from 2 ng mL^–1 to 200 ng mL^–1 and from 10 ng mL^–1 to 150 ng mL^–1, with the limits of detection of 0.2 ng mL^–1 and 0.5 ng mL^–1, respectively. This sensing system with triple structure owned better specificity to structural and functional analogues, showed good repeatability and stability. What's more, this sensing system could be applied to actual water detection, with the recoveries of 86.1%–107.4%, and the relative standard deviation below 6.8%. This method shows promising applications in other environmental estrogens in water sample.     

Cationic conjugated polymers as signal reporter for label-free assay based on targets-mediated aggregation of perylene diimide quencher

Herein, we reported a cationic conjugated polymers-based new biosensor with label-free and fluorescence turn-on strategy by virtue of targets regulated aggregation and quenching ability of perylene diimide derivatives.     

环氧树脂微粒化水基化体系

本文系统介绍了环氧树脂微粒化水基化体系的特点及用途，制备方法和反映体系特性的一些重要参数。