Honeycomb micropatterning of proteins on polymer films through the inverse microemulsion approach

Here we report the rapid and convenient patterning of proteins on porous polymer film using the inverse microemulsion approach. Following this method, proteins, which were dissolved in water, were transferred into dichloromethane solution of polymers through the formation of inverse microemulsion by mixing the two solutions. The protein-containing microemulsion droplets accumulated automatically into large and stable ones on the surface of organic solution casting on solid substrates, and formed tightly packed microemulsion droplet arrays driven by surface tension. With the evaporation of organic solvent and water, the microemulsion droplet arrays, which act as the template, turn to honeycomb patterned pores bearing proteins in them. The formed protein patterns can be locally applied for the detection of other proteins through specific recognition. The generality and reproducibility for the formation of BSA/PS microporous film and protein patterning by using different polymers and solvents were demonstrated by investigating surfactant addition, polymer and solvent types, and casting volume on the morphology of the microporous films. A preliminary mechanism for the protein patterning is discussed based on the analysis of the experimental results.     

吲哚方酸菁染料在表面活性剂水溶液中的光降解

考察了4种含有不同N位取代基的对称吲哚方酸菁染料在阳离子表面活性剂十六烷基三甲基溴化铵(CTAB)、阴离子表面活性剂十二烷基硫酸钠(SDS)和非离子表面活性剂曲拉通(TX-100)水溶液中的光降解行为,结果表明,表面活性剂对染料分子具有保护作用,其影响大小为CTAB>TX-100>SDS,分子中有羧基的染料受影响程度最大。在表面活性剂浓度较低时,染料光降解程度随着表面活性剂浓度的增加而增加,但形成胶束后,染料的光降解程度则随着表面活性剂浓度的升高而降低。     

差分方程拉克斯对的一种构造性方法

非交换微分在讨论数学物理中的偏微分方程时起着十分重要的作用.最近,作者利用一个具体的非交换外微分建立了一种求差分微分方程拉克斯对的方法,由此检验了该方程的可积性.本文给出了讨论全差分方程的对应理论.另外还讨论了一个格子形变的KdV(LMKdV)方程,并求得了它的拉克斯对.     

Use of Multiwalled Carbon Nanotubes as a SPE Adsorbent for Analysis of Carfentrazone-Ethyl in Water

Solid-phase extraction and gas chromatography with electron-capture detection has been used for sensitive, simple, and reliable analysis of carfentrazone-ethyl residues in water. Carfentrazone-ethyl was enriched by use of multiwalled carbon nanotubes (MWCNT), a new adsorptive material. Several conditions affecting recovery of the analyte, for example polarity and volume of eluents, pH of water samples, and sample volume, were studied. Recovery from fortified samples, linear range, and limit of detection were evaluated. The results showed that MWCNT are an efficient SPE adsorbent for preconcentration of carfentrazone-ethyl in water. Under the optimized SPE conditions, recovery of carfentrazone-ethyl from fortified water was 81.49–91.08%, with RSD from 1.66 to 8.21%. The limits of detection and quantification were 0.01 and 0.03 µg L^?1, which were lower than the MRL stipulated by the EU for individual pesticides in water (0.1 µg L^?1). Finally, the method was applied to tap water and river water; the results showed that the method was suitable for detection of carfentrazone-ethyl in environmental water samples.     

Electrochemiluminescence for probing interactions between a mimic enzyme and biological molecules

The present work proposed a novel ECL protocol to probe the interactions between mimic enzymes and small biological molecules. Iron(II) phthalocyanine (FePc) and two imidazoles (imidazole and histidine) were chosen as model molecules of mimic enzyme and small biological molecules, respectively. The interactions between FePc and the imidazoles were probed by a sensitive luminol–O₂ ECL system. Before complexing with the imidazoles, FePc can inhibit luminol–O₂ ECL due to its electrocatalysis towards O₂, however, after complexing with the imidazoles, FePc decreases the electrocatalysis, leading to the observation of an enhanced luminol–O₂ ECL. Additionally, the proposed protocol enables detection limits of 1.0 × 10^?8 mol L^?1 and 1.0 × 10^?7 mol L^?1 to be achieved, respectively, for imidazole and histidine under the physiological pH condition (pH 7.4).     

Highly Conductive Films of Layered Ternary Transition‐Metal Nitrides

Film studies : Epitaxial films of BaZrN₂ (see TEM image) and BaHfN₂ are grown by polymer‐assisted deposition on SrTiO₃ (STO) substrates. The films are phase‐pure, allowing the intrinsic physical properties of the ternary nitrides to be studied. From 5 to 300 K, the films exhibit metallic‐like resistivity–temperature behavior, with large residual resistivity ratios.

     

含有手性和发光官能团侧基的聚1-苯基-1-辛炔的合成与性能研究

设计并合成了一系列含手性和发光生色团侧基的聚（1-苯基-1-辛炔）衍生物{-[（C6H13）C=C（C6H4-p-CO2-R）]n-,R=[（1S）-endo]-（-）-冰片基（P3）,（1R,2S,5R）-（-）-薄荷基（P4）,-C6H4-p-（1R,2S,5R）-（-）-薄荷基（P5）,2-萘基（P6）,4-联苯基（P7）}.用WCl6-Ph4Sn作催化剂,成功地制备了这些具有中等产率和高分子量（Mw高达64000）的聚合物.聚合物的结构和性能通过NMR,TGA,UV,CD,PL和EL等分析方法进行了表征.所有聚合物都表现出良好的热稳定性,在N2保护条件下,其失重5%的温度在300～416℃之间.所有聚合物的带隙约为3.0eV.聚合物P4和P5表现出与聚合物链段螺旋性相对应的CD吸收.在UV辐照下,P3～P7的THF溶液均发射强烈蓝光,其最大发射波长位于485nm左右,量子效率均高于20%.聚合物薄膜发射与其溶液发射在相同的光谱区域,并表现出轻微的聚集诱导猝灭.制备了ITO/聚合物：PVK/BCP/Alq3/LiF/Al多层聚合物EL器件,其最大发射波长为487nm.随着侧基的改变,器件的最大亮度和外量子效率也随之发生变化,其中P6表现出最高的外量子效率（0.16%）.EL器件均具有良好的光谱稳定性,其EL最大发射峰几乎不随外加电压的变化而改变.     

A robust algorithm for generalized geometric programming

Most existing methods of global optimization for generalized geometric programming (GGP) actually compute an approximate optimal solution of a linear or convex relaxation of the original problem. However, these approaches may sometimes provide an infeasible solution, or far from the true optimum. To overcome these limitations, a robust solution algorithm is proposed for global optimization of (GGP) problem. This algorithm guarantees adequately to obtain a robust optimal solution, which is feasible and close to the actual optimal solution, and is also stable under small perturbations of the constraints.     

自适应分段时域质心特征在鱼类识别中的应用

提出了一种基于时域质心的时域自适应分段方法。该方法以时域质心为依据对信号的时域进行划分,在划分的各个子段内计算时域质心,并将其作为下一层划分的分割点。各个子段内的时域质心反映了信号的能量分布特性,可作为识别特征量。对三种常见的不同形状的鱼类进行了水池试验,提取自适应分段时域质心特征,并使用BP神经网络分类器成功进行了分类。结果表明:利用自适应分段时域质心特征可对不同形状的鱼类进行识别,且具有较高的识别率。     

Effect of Mercaptocarboxylic Acids on Luminescent Properties of CdTe Quantum Dots

CdTe quantum dots (QDs) were prepared in an aqueous solution using various mercaptocarboxylic acids, such as 3-mercaptopropionic acid (MPA) and thioglycolic acid (TGA), as stabilizing agents. The experimental result indicated that these stabilizing agents played an important role for the properties of the QDs. Although both TGA and MPA-capped CdTe QDs exhibited the tunable photoluminescence (PL) from green to red color, the TGA-capped QDs revealed a higher PL quantum yield (QY) up to 60% than that of MPA-capped QDs (up to 50%) by using the optimum preparation conditions, such as a pH value of ~11.2 and a TGA/Cd molar ratio of 1.5. PL lifetime measurements indicate that the TGA-capped QDs exhibited a short average lifetime while the MPA-capped QDs revealed a long one. Furthermore, the average lifetime of the TGA-capped QDs increased with the increase of the QDs size, while a decreased lifetime for the MPA-capped QDs was obtained. This means that the PL lifetime depended strongly on the surface state of the CdTe QDs. These results should be utilized for the preparation and applications of QDs.