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通过介绍圆形料场机械结构、机构工作原理、供电系统、电气控制架构、操作方式及联锁系统。设计了圆形料场整体采用PLC控制系统,因此提高了设备自动化水平,降低了运行及维护成本,对完善物料运输起到重要意义。 相似文献
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Ruifen Chen Yonggang Shangguan Chunhui Zhang Feng Chen Eileen Harkin-Jones 《Polymer》2011,52(13):2956-2963
The phase structure evolution of high impact polypropylene copolymer (IPC) during molten-state annealing and its influence on crystallization behaviour were studied. An entirely different architecture of the IPC melt was observed after being annealed, and this architecture resulted in variations of the crystallization behaviour. In addition, it was found that the core-shell structure of the dispersed phase was completely destroyed and the sizes of the dispersed domains increased sharply after being annealed at 200 °C for 200 min. Through examination of the coarseness of the phase morphology using phase contrast microscopy (PCM), it was found that a co-continuous structure and an abnormal ‘sea-island’ structure generally appeared with an increase in annealing time. The original matrix PP component appeared as a dispersed phase, whereas the copolymer components formed a continuous ‘sea-island’ structure. This change is ascribed to the large tension induced by solidification at the phase interface and the great content difference between the components. When the temperature was reduced the structure reverted to its original form. With increasing annealing time, the spherulite profiles became more defined and the spherulite birefringence changed from vague to clear. Overall crystallization rates and nucleation densities decreased, but the spherulite radial growth rates remained almost constant, indicating that molten-state annealing mainly affects the nucleation ability of IPC, due to a coarsened microstructure and decreased interface area. 相似文献
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【】随着个人电脑、互联网的发展,云电视技术已经得到了广泛的应用。涉及云电视技术的发明专利申请量从2011年开始迅速增加。本文基于有关云电视技术的专利文献,从国际专利分类IPC入手,介绍了云电视技术领域相关的分类号分布情况,从而为相关人士提供从分类号入手检索自己感兴趣的云电视技术相关专利文献的方法参考。 相似文献
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Chunhui Zhang Yonggang Shangguan Ruifen Chen Yuanzhi Wu Feng Chen Qiang Zheng Guohua Hu 《Polymer》2010,51(21):4969-1792
The morphology of impact polypropylene copolymer (IPC) was studied through scanning electron microscope (SEM) and transmission electron microscope (TEM) observation, and a modified dispersed phase model of IPC with core-shell structure was proposed. Through fractionation of IPC, the glass transitions of the ethylene-propylene random copolymer (EPR) fraction, ethylene-propylene block copolymer (EbP) fraction and propylene homopolymer (iPP) fraction were detected, respectively. Moreover, the glass transitions and crystallization behaviors of EbP/iPP and EPR/EbP fraction blends were systemically investigated and several reasonable chain structures of EbP component were confirmed. The results reveal that the EbP component presents three glass transition peaks, and the glass transition temperature of ethylene-propylene random copolymer in IPC sample is remarkably lower than that of pure EPR fraction due to the existence of special structure of EbP component in IPC. In addition, co-crystallization occurring between the polypropylene chains in EbP fraction and in iPP fraction was found for solution-mixed EbP/iPP blends, and it is believed that there exists a dilute effect of EPR on the crystallization of EbP fraction for the solution-mixed EPR/EbP blends. Accordingly, it can be inferred that EbP fraction has good compatibility with both EPR and iPP fraction, and indeed it confirms that the compatibilization effect of EbP fraction in IPC was good. 相似文献