Novel polycationic biocides: Synthesis and antibacterial activity of polymeric phosphonium salts

Various polymeric phosphonium salts and the corresponding low-molecular-weight model compounds were prepared and their antibacterial activities against Staphylococcus aureus and Escherichia coli were explored by the viable cell counting method in sterile distilled water. Antibacterial activity of the polymers was found to be higher than that of the corresponding model compounds, particularly against S. aureus. Furthermore, the polymeric phosphonium salt exhibited a higher activity by 2 orders of magnitude than the polymeric quaternary ammonium salt with the same structure except the cationic part. Compounds with the longest alkyl chain (octyl) studied were found to exhibit particularly high activity, and this finding may be ascribed to the contribution of the increased hydrophobicity of the compounds to the cidal activity. © 1993 John Wiley & Sons, Inc.     

Generalization of in-situ polymerization method for preparing core-shell polymeric nanospheres and hollow spheres

According to the new method of preparing core-shell nanospheres developed by our group, by using two monomers, 2-hydroxypropyl methacrylate(HPMA) and vinyl acetate(VAc), two kinds of core-shell nanospheres with poly(ɛ-caprolactone) (PCL) as the core and crosslinked poly(2-hydroxypropyl methacrylate) (PHPMA) or poly(vinyl acetate) (PVAc) as the shell were successfully prepared under similar conditions. After degrading the PCL cores of the two kinds of nanospheres by lipase, the corresponding crosslinked poly(methyl acrylic acid) hollow spheres and crosslinked poly(vinyl alcohol) hollow spheres were obtained. Results indicate that the new method we proposed for preparing core-shell polymeric nanospheres via in-situ polymerization can be generalized to a certain extent, and it is suitable for many systems provided the monomer used is soluble in water, while its corresponding polymer is insoluble in water. Translated from Chemical Journal of Chinese University, 2006, 27(9): 1762–1766 [译自: 高等学校化学学报]     

功能化离子液体中Ag纳米微粒的制备及摩擦学性能研究

合成了1-甲基-3-羟乙基咪唑四氟硼酸盐离子液体([C₂OHmim]BF₄)，用红外光谱表征了其结构。以所合成的离子液体作为还原剂、稳定剂与反应介质制备了Ag纳米微粒，用XRD和TEM对微粒的结构和形貌进行了表征。在四球摩擦磨损实验机上研究了[C₂OHmim]BF₄离子液体及掺入Ag纳米微粒后的离子液体的摩擦学性能。掺入银纳米微粒后，离子液体在高载荷下的润滑性有了大幅的改善。用SEM和XPS分别对磨痕表面的形貌和元素组成、化学状态进行了分析，结果表明：在低、高载荷分别起润滑作用的是有机膜和金属-有机复合膜。     

The Intelligent Properties of Micro－reactors for Preparating Nanoparticles

TiO2 nanoparticles were synthesized by using micro-reactors. The shape and size of the nanoparticles produced from the original micro-reactors and the five times recycled micro-reactorsmother liquor were investigated on transmission electron microscopy (TEM) by using the original sample, freeze prepared sample, and dyeing treated sample, respectively. UV-VIS spectrometry was used to study the growth process of TiO2 nanoparticles in main reactors. The results showed that micro-reactors with nanometer magnitude had spherical or oval structures, and could restore to their original structure after they were destroyed. The products prepared in the original micro-reactors were similar to that in the micro-reactors recycled for many times, suggesting that the micro-reactors had memory function.     

单分散磁性纳米颗粒的制备及生物高分子在其上的组装

磁性纳米颗粒因其潜在的生物医学应用价值而成为纳米生物材料领域研究的前沿。本文综述了单分散磁性纳米颗粒的制备方法以及生物高分子在磁性纳米颗粒上的组装的研究进展。     

Investigation of polymer-protected noble metal nanoparticles by transmission electron microscopy: control of particle morphology and shape

 Noble metal nanoparticles were prepared by the in situ reduction of the respective metal salt precursors in the presence of various protective polymers. Transmission electron microscopy (TEM) has been used to determine the particle shapes and morphologies. These are strongly influenced by the reduction methods and conditions chosen, but the choice of the protective polymer is equally important for controlling the particle morphologies and for the stabilization of the colloids. A whole spectrum of nanoparticle morphologies and shapes was obtained, ranging from nanoagglomerates which are nevertheless well-defined and well-stabilized to nanosized single crystals with triangular shape. Received: 2 February 1998 Accepted: 29 May 1998     

Synthesis and Crystal Structure of a New Organic-inorganic Hybrid One-dimensional Polymer： [Zn（C8H23N5）]2（Pb3I10）

1 INTRODUCTION Recently, the organic-inorganic hybrid Ⅳa groupmetal halides with low-dimensional structure haveattracted much attention of chemists and physicistsdue to their particular properties and applications.For example, they are akin to “natural quantum-well”architectures and have tunable excitonic propertiesusually governed by the inorganic substructure andorganic component[1]; they have been applied assome technologically important materials, such assemiconductor materials in …     

Synthesis and Magnetic Properties of Fe（Ⅱ） and Nd（Ⅲ） Complexes of Poly（N-2-thiazolylacrylamide）

N-2-Thiazolylacrylamide （NTA） was polymerized by a radical route to obtain the polymer in good yield. The polymer with a pendent heterocyclic group is soluble in common organic solvents, which allow to prepare the corresponding metal complexes with higher loads easily. FTIR, ^1H NMR, elemental analysis, and energy-dispersive X-Ray spectroscopy （EDX） were applied to characterize these materials. The magnetic behavior of Fe（Ⅱ） and Nd（Ⅲ） complexes of poly（N-2-thiazolylacrylamide） was examined by a PPMS-9T magnetometer, exhibiting the characteristics of a soft ferromagnet. It is found that the Nd（Ⅲ） complex has an extremely high relative saturation magnetization of 35 emu/g.     

磁性纳米标记检测技术在生物医学即时检测领域的研究进展

基于磁性纳米材料的磁标记检测技术具有灵敏度高、线性范围广、信号检测便捷等优点。由于生物样品自身磁背景信号极低,相比于光学标记检测技术,磁标记检测技术在蛋白质、核酸、细胞、病原体及生物组织检测中均表现出更高的灵敏度,在生物医学即时检测领域展现了良好的应用前景。该文围绕磁性纳米粒在即时检测领域的最新研究进展,重点介绍了其在蛋白质、核酸以及几类病原体检测方面的应用,并对基于磁性纳米粒的即时检测技术发展方向及应用前景进行了展望。     

Comparison between self-reinforced composites based on ultra-high molecular weight polyethylene fibers and isotropic UHMWPE

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