PSA和PPS耐高温纤维的结构与性能研究

通过红外光谱仪和X-射线衍射仪测定芳砜纶(PSA)纤维和聚苯硫醚(PPS)纤维的微观结构,用热分析仪测定两者的热分解温度,通过Instron电子强伸度仪测定两者受热前后的力学性能,并对两者结构与性能的差异进行比较。结果表明:PPS纤维的结构较PSA纤维稳定,结晶度高于PSA纤维;PSA纤维和PPS纤维的热分解温度分别为435.6℃和480℃,两种纤维均具有优异的耐热性能;PPS纤维的断裂强度和伸长均显著高于PSA纤维,两种纤维经高温处理后,强力损失均较小,经300℃处理200h后,强力仍保持90%左右。     

在新一代DSP密集型系统中实现更高的性能和更低的成本

当与IDT的中央包交换器(CPS)/预处理交换器(PPS)同时使用时,具有串行RapidIo功能的IDT 10G串行缓冲器可将系统性能提高20%以上.在现实应用中,这个解决方案可将材料清单(BoM)减少50%～75%.本文基于IDT公司的IOG串行缓冲器和CPS/PPS,介绍了一种采用DSP集群的3G蜂窝基站系统设计方法.     

聚苯硫醚的特性分析及其注塑成形研究

聚苯硫醚（PPS）全称聚苯基硫醚，是一种性能优异的特种工程塑料，也是一种结晶性树脂。叙述了聚苯硫醚的化学结构及其性能特点；研究分析了聚苯硫醚的成形工艺。     

利用GPS对计算机实现精确授时

阐述了如何利用GPS对单个计算机进行精确授时。系统利用软件，从GPS接收器获取UTC时间码和秒定时信息，并对计算机时钟进行校准。该系统具有投资省、精度高、用途广等特点，取得了满意的效果。     

Photocatalytic performance of rich OVs-BiOCl modified by polyphenylene sulfide

Introduction of oxygen vacancies (OVs) on the surface of photocatalyst has been proved to be a potent avenue to improve photocatalytic capability by accelerating the segregation of photoactivated carriers and creating a defect energy level. In this presentation, a facile hydrothermal approach was performed to fabricate polyphenylene sulfide (PPS)/OVs-BiOCl composites to further improve the catalytic capability of OVs enriched BiOCl. The successful construction of rich OVs in BiOCl was firmly confirmed by X-ray photoelectron spectroscopy (XPS) and low- temperature electron spin resonance (ESR). Surface photovoltage spectrum (SPS) and electrochemical characterization display that the existence of PPS in the synthetic system dramatically affects the surface states of BiOCl, expediting the segregation of photoinduced carriers. Photocatalytic capacity of PPS/OVs-BiOCl was examined by disintegration of perfluorooctanoic acid (PFOA), rhodamine B (RhB) and tetracycline (TC). PPS surface modification can significantly improve the photoactivity of OVs-BiOCl toward destruction of PFOA, RhB and TC. Interestingly, when mass ratio of PPS/BiOCl is 0.5%, the degradation capacity of PPS/OVs-BiOCl for decontamination of RhB and TC is 4.25 and 3.10 -fold higher than that of OVs-BiOCl, respectively. In consideration of the observations, the photocatalytic enhancement mechanism for PPS/OVs-BiOCl was elaborated.     

All-optical wavelength reuse with simultaneous upstream data and PPS timing signal transfer for flexible optical access networks

All-optical wavelength reuse is a viable approach for realization of low cost colourless ONUs. We experimentally demonstrate a novel all-optical wavelength reuse technique with simultaneous upstream data and pulse-per-second signal transfer, exploiting EDFA gain saturation with a holding beam. A DFB laser is modulated with 8.5 Gbps data and transmitted downstream over 24.7 km fibre. A saturated EDFA located at the ONU is adopted to reduce the extinction ratio of the downstream data from 6.2 dB to 839.1 mdB. This allows for data rewrite and wavelength reuse for upstream transmission. Receiver sensitivities of ?20.19 dBm and ?19.60 dBm are achieved at back-to-back analysis and 24.7 km downstream link respectively. A holding beam is further exploited to attain simultaneous carrier reuse and PPS clock upstream transfer. PPS jitter stability of 1.01 × 10^-08 ns and 6.64 × 10^-08 ns are attained respectively. This work offers a convenient all-optical wavelength reuse solutions for optical access networks.     

Towards an integrated measurement of IS project performance: The project performance scorecard

Determining the contribution of information system (IS) projects is a difficult endeavour. This research presents a framework for evaluating and measuring IS project performance that seek to address this problem while moving away from the reliance on the traditional assessment method (time, cost, specifications). When IS projects fail or succeed is difficult to determine what conditions enabled the outcome. However, if we are to develop a higher level of IS project management competence we need frameworks that can help in assessing IS project outcomes while critically reflecting and learning from IS project management practices. The Project Performance Scorecard (PPS) recommended here is one framework that can help to advance our understanding IS project management and evaluation approaches. This framework integrates concepts from existing models of IS success, the Balanced Scorecard and project management practices. A case study approach is used to illustrate the use of the PPS, and offers insights into how it can be useful in assessing the performance of IS projects.

浅谈PPS导向系统

介绍PPS导向系统的工作原理,提出系统运行过程中的管理维护内容与措施,根据PPS系统的定位原理,了解TBM在掘进过程中的偏差因素,采取对其纠偏的措施,可保证TBM严格按设计坐标方位掘进。     

聚苯硫醚与不锈钢纤维混纺织物的工艺设计及性能研究

利用聚苯硫醚纤维的阻燃性及不锈钢纤维优异的防辐射性能、抗静电性能,选用六种不同混纺比的纱线,通过变换组织结构设计织造出十二种织物,并对其进行性能测试。结果表明,当织物中不锈钢含量增加时,织物的防辐射性能显著提高,织物的抗静电性能显著增强。聚苯硫醚纤维本身就有很好的阻燃性能,因此,加入不锈钢对织物阻燃性的影响不太显著,但对阻燃效果有益。     

几种芳香族高性能纤维性能改进研究

芳香族纤维因具有刚性链结构和良好规整性而拥有高强高模、耐高温等性能,被广泛应用于众多产业。介绍了芳纶、聚苯硫醚,聚对苯撑苯并双噁唑三种芳香族纤维的性能特征,详细指出其产业化应用在耐紫外性能、染色性能、界面黏结性和压缩性能方面的不足。此外,还根据现有资料回顾了芳香族纤维在这些方面的改性方法及效果。