Twining Poly(polyoxometalate) Chains into Nanoropes

Organic polymers and inorganic clusters belong to two different disciplines and have completely different properties and structures. When a cluster is attached to the backbone of a polymer as a pendant, the resultant hybrid polymers (polyclusters) exhibit unique behaviours totally different from those of conventional polymers owing to the nanoscale size of the cluster and its particular interactions. Herein, the aggregation of a poly(polyoxometalate)—a polynorbornene backbone with inorganic polyoxometalate cluster pendants—upon addition of a non-solvent to its dilute solution is reported. A three-dimensional network of tangled and snake-like nanothreads was observed. Direct visualisation of individual nanoscale clusters enabled identification of single chains within the nanothreads. These observations suggest that during the process of aggregation, the hybrid polymer forms curved or extended chains as a consequence of an armouring effect in which the collapsed cluster pendants wrap around the backbone. The collapse occurs because they become less soluble in the solvent/non-solvent mixture. The extended chains then become entwined and form nanoropes consisting of multiple chains wound around each other. This study provides a deeper understanding of the nature of polyclusters and should also prove useful for their future development and application.     

对高职数控专业毕业综合实训的探讨

本文探讨了数控技术专业毕业综合实训的改革思路，提出按职业资格标准强化技能培训，使学生在毕业前获得数控机床操作职业资格证书，切实提高学生的职业素质与就业竞争能力。     

现代教学媒体及其应用的探讨

教学媒体是现代教育技术的重要组成部分，它是人类社会发展的成果之一，文章对各类现代教学媒体进行了探讨。     

<Emphasis Type="Italic">FCC/BCC</Emphasis> competition and enhancement of saturation magnetization in nanocrystalline Co-Ni-Fe films

The structure, chemical composition, and magnetic properties of electrochemically deposited nanocrystalline Co-Ni-Fe films were investigated using a number of techniques. A high saturation magnetic induction up to B _s = 21 kG was attained. An enhancement of the saturation magnetization compared to the ideal anticipated one was revealed, which correlated with the nonlinear behavior of the structural phase composition and lattice parameters with the change of the composition. The text was submitted by the authors in English.     

Reconsideration on Homogeneous Quadratic Riemann Boundary Value Problem

The homogeneous quadratic Riemann boundary value problem (1) with Hoelder continuous coefficients for the normal case was considered by the author in 1997. But the solutions obtained there are incomplete. Here its general method of solution is obtained.     

增加农民收入刍议

农民的收入水平不仅与农村居民的生活状况密切相关,而且关系到农村经济以及整个国民经济的发展。千方百计地增加农民收入,是我国当前农村工作的主要任务。积极地发展大城市是增加农民收入的有效途径之一。     

基于PLC的LED显示电路的研究

介绍了几种LED显示电路．为减少硬件设置，节省PLC的I／0点，提高系统的性价比具有积极的意义．该显示电路在设计中已应用，实践证明是可行的，值得推广．