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1.
Lan-Lan Zhang Dr. Wen-Ke Miao Dr. Li-Jun Ren Yu-Kun Yan Dr. Yue Lin Prof. Wei Wang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(58):13396-13401
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. 相似文献
2.
Discrete time queueing systems have been successfully used to model packet queues in computer and digital communications systems. In this article we introduce a novel approach to analyzing the GeoX/GeoY/∞ queueing system, which is suitable for modelling high speed computer and communications systems. The approach is based on characterizing the system by a functional equation which is then solved recursively to give identical results to those obtained using other approaches. 相似文献
3.
提出在县市级广电宽带数据网络的建设过程中,要着眼业务发展,突出高扩展性,构建基于标准、扩展灵活的主干网,实现网络建设的可持续性发展,并结合实际,从核心设备、端口、中继带宽、网络业务4个方面对扩展能力进行了阐述. 相似文献
4.
Xu Baowen Zhang Weifeng 《电子科学学刊(英文版)》2002,19(4)
The users' interest can be mined from the web cache and can be used widely. The interest can be specialized by the two-tuple (term, weight) in the simple interest model, in which the association relations are not mined, and then the interest cannot be associated in expressing the users' interest. Based on analyzing the WWW cache model, this letter brings forward a two-dimensional interest model and gives the interrelated methods on how to store the two-dimensional interest model effectively. 相似文献
5.
XuBaowen ZhangWeifeng 《电子科学学刊(英文版)》2002,19(4):399-402
The users‘ interest can be mined from the web cache and can be used widely.The interest can be specialized by the two-tuple(term,weight) in the simple interest model,in which the association relations are not mined.and then interest cannot be associated in expressing the users‘interest.Based on analyzing the WWW cache model,this letter brings forward a twodimensional interest model and gives the interrelated methods on how to store the two-dimensional interest model effectively. 相似文献
6.
系统备份及其误区分析 总被引:1,自引:0,他引:1
张军华 《微电子学与计算机》2002,19(9):34-35
文章对系统备份的几个主要方面进行了讨论,并在此基础上,对系统备分的若干认识误区进行了分析。 相似文献
7.
基于多传感器数据融合方法的火灾模拟实验炉温度采集系统 总被引:6,自引:1,他引:5
基于多传感器算术平均值与分批估计的数据融合方法在火灾模拟实验炉上温度数据采集中的应用,用VB6.0开发了相应的实际应用系统。 相似文献
8.
9.
Takeshi Kondo Sang Min Lee Michal Malicki Benoit Domercq Seth R. Marder Bernard Kippelen 《Advanced functional materials》2008,18(7):1112-1118
We report on a single‐layer organic memory device made of poly(N‐vinylcarbazole) embedded between an Al electrode and ITO modified with Ag nanodots (Ag‐NDs). Devices exhibit high ON/OFF switching ratios of 104. This level of performance could be achieved by modifying the ITO electrodes with some Ag‐NDs that act as trapping sites, reducing the current in the OFF state. Temperature dependence of the electrical characteristics suggest that the current of the low‐resistance state can be attributed to Schottky charge tunnelling through low‐resistance pathways of Al particles in the polymer layer and that the high‐resistance state can be controlled by charge trapping by the Al particles and Ag‐NDs. 相似文献
10.
说明了在异步串行通信(RS-232)的工作方式下,对所接收的数据进行接收、处理,丢弃乱码,并进行保存的可靠方法,并给出了相关的VC 语言程序. 相似文献