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41.
Zixiao Pan Wei Wei Fuhe Li 《Journal of Materials Science: Materials in Electronics》2011,22(10):1594-1601
To keep up with the trend of integrating more functionality within lighter and smaller consumer electronics devices, the dimensions of components keep shrinking. Technologies such as high density interconnection, 3-D interconnection, system in package (SIP), and flexible circuit are becoming more commonly used. The smaller dimensions of the conductors and insulators (spacing) used in these technologies make them more sensitive to chemical contamination. Trace amounts of chemical contamination introduced during the manufacturing process or in the field can cause device failures. The failure mechanisms include inversion-induced leakage current, corrosion, and electro-chemical migration, to name a few. The complexity of materials used in a highly integrated system also poses new challenges for fault isolation and chemical characterization in failure analysis. This paper calls attention to the selection of appropriate analytical techniques in terms of spatial resolution and sensitivity, sample preparation complexity, throughput, and detection limitations. We present two failure analysis cases in which LA-ICP MS, in conjunction with other analytical techniques, was successfully used to identify the source of chemical contamination and the root cause. 相似文献
42.
介绍了设计双流道筒体的必要性,通过建立物理、数学模型详细论述了双流道筒体的设计原理及换热计算过程,并通过试验对比分析验证了模型的可靠性,同时对单、双流道筒体的换热能力进行对比分析,得出了可靠的结论. 相似文献
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E Franco L Toti R Gabrieli L Croci D De Medici A Panà 《International journal of food microbiology》1990,11(3-4):321-327
Mussels (Mytilus galloprovincialis) were contaminated with known amounts of laboratory strains of hepatitis A virus and Poliovirus 1 and the effectiveness of a self-cleansing mechanism was studied using a pilot depuration system. Both viruses were rapidly bioaccumulated by mussels and the maximal concentration of about 10(4) TCID50/ml was reached within 1.5 hours. Depuration was carried out up to 24 h; infectivity titer decreased to 10(2) TCID50/ml and 10(3.2) TCID50/ml within 6 h in hepatitis A virus and Poliovirus 1 contaminated mussels, respectively, but only a very slight further decrease was obtained after 24 h. E. coli was used as a control; within 24 h the concentration decreased from 40 to 2 bacteria/ml of mussel (MPN). The elimination of bacteria is not a reliable parameter to control the effectiveness of viral depuration. 相似文献
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47.
S. Pan C. Lou 《Photonics Technology Letters, IEEE》2006,18(13):1451-1453
We demonstrate a stable multiwavelength actively mode-locked erbium-doped fiber laser at 10 GHz based on a dispersion cavity and nonlinear polarization rotation (NPR) effect. The dispersion cavity allows simultaneous multiple wavelengths to satisfy the round-trip condition and smooth wavelength tuning, while the NPR ensures the stable operation and supermode noise suppression. A simple model is developed to explore the optimal setting of the cavity. Simultaneous dual- and five-wavelength operation is experimentally investigated. 相似文献
48.
Vijay S Kumar Benjamin Rutt Tahsin Kurc Umit V Catalyurek Tony C Pan Sunny Chow Stephan Lamont Maryann Martone Joel H Saltz 《IEEE transactions on information technology in biomedicine》2008,12(2):154-161
This paper presents the application of a component-based Grid middleware system for processing extremely large images obtained from digital microscopy devices. We have developed parallel, out-of-core techniques for different classes of data processing operations employed on images from confocal microscopy scanners. These techniques are combined into a data preprocessing and analysis pipeline using the component-based middleware system. The experimental results show that: 1) our implementation achieves good performance and can handle very large datasets on high-performance Grid nodes, consisting of computation and/or storage clusters and 2) it can take advantage of Grid nodes connected over high-bandwidth wide-area networks by combining task and data parallelism. 相似文献
49.
基于干涉仪动态相移的光纤激光器跳模检测方法 总被引:3,自引:0,他引:3
针对已有方法在单频光纤激光器跳模检测中存在的不足,提出一种基于非平衡光纤Michelson干涉仪动态相移的跳模检测方法。使用干涉仪将激光器跳模时的光频突变转换为相位工作点的突变,并通过同步监测相位工作点的正余弦函数两路信号来跟踪与判断它的动态相移,成功实现了对超窄线宽掺铒光纤环形激光器偶发的随机跳模以及由开机瞬态热效应触发的连续多次跳模的测量与分析。结果表明,该方法检测灵敏度高,跳模判据实时直观,并能测量跳模前后可能发生的频漂,为评价单频光纤激光器的模式稳定能提供有效的测试手段。 相似文献
50.
Li-Yan Pan Jia-Wei Liu Jin-cheng Mao Hai-Bin Wang 《Petroleum Science and Technology》2017,35(8):747-753
We, the Editor and the Publisher of Petroleum Science and Technology, have retracted the following article:Li-Yan Pan, Guo-Qing Feng, Jin-cheng Mao &; Hai-Bin Wang. “Oil soluble polymers as a viscosity-reducing agent for super heavy oil,” Petroleum Science and Technology, Volume 35, 2017, Issue 8, pages 747–753. doi:10.1080/10916466.2016.1273240We are now cognizant of the fact that the above article has substantial text-matching with the following article, to which no attribution was made:Jincheng Mao, Jiawei Liu, Haibin Wang, Xiaojiang Yang, Zhaoyang, Bo Yang &; Jinzhou Zhago. “Novel terpolymers as viscosity reducing agent for Tahe super heavy oil,” RSC Advances, Volume 7, 2017, Issue 31, pages 19257–19261.It is therefore not deemed to be an original contribution. We note the breach of warranties made by the authors with respect to originality and provenance, and of our policy on publishing ethics and integrity. We note that we received, peer-reviewed, accepted, and published the article in good faith based on these warranties, and censure this action.We have been informed in our decision-making by our policy on publishing ethics and integrity and the COPE guidelines on retractions. The retracted article will remain online to maintain the scholarly record, but it will be digitally watermarked on each page as “Retracted”. 相似文献