稠油热采井改性纤维复合防砂实验研究

单一的防砂技术在稠油热采井中的应用受到一定限制，为解决热采井防细粉砂，从改善纤维复合防砂技术体系中的基体（树脂涂敷砂）性能入手，以期使纤维复合防砂技术能够用于热采井防砂。通过考察水溶性酚醛树脂、ER树脂粉末、偶联剂、增强剂加量对砂体抗压强度和渗透率的影响，分析了体系中各组分的作用机理。通过室内实验优化了纤维防砂体的配方，研究表明，偶联剂、改性剂、增强剂、ER树脂粉末、水溶性酚醛树脂SR1、石英砂之间的质量比为（0.15~0.20）∶3.1∶1.5∶（2~4）∶10∶100时体系具有较高的防砂强度，并且在350℃下仍能保持在3MPa左右，较不加入纤维时高30%，渗透率可增加10%左右。     

Not only men but also migrants in non-traditional occupations

Domestic labour is considered a typical female job, and due to the arrival of large migration flows to Italy it has experienced a massive ethnicized connotation, peculiar of this sector. This paper focuses on how a double and subaltern condition of belonging to a ‘minority group’ affects gender perceptions of male migrant domestic workers and how they construct their masculinity.

This research is based on a comparison between 54 interviews with male and female migrant domestic workers, drawing on an intersectional approach based on gender and nationality. It shows how moving across borders, living in a host society, and working in a non-traditional job can reshape male immigrants' gender division perceptions, often in contradictory and unexpected ways. It also emerges how the ‘racial glass escalator’ allows reaffirmation of characteristics tied to the privileges of masculinity and furnishes an important and useful framework in which to analyse the experience of men in ‘female’ occupations.     

恒电流下聚乙烯醇纤维水泥基复合材料钢筋锈蚀率的研究

湿通电法是加速聚乙烯醇纤维水泥基复合材料中钢筋锈蚀的一种有效方法。在本试验中将电流设定为一恒定值,测试在不同聚乙烯醇（ polyvinyl alcohol 简称PVA）纤维掺量下的闭合回路电阻;以及在NaCl溶液侵蚀下PVA纤维水泥基复合材料的钢筋锈蚀率。试验结果表明,恒电流条件下,PVA纤维掺量的增加能提高水泥基复合材料的抗渗性,但对钢筋锈蚀率影响不大。     

Introduction to critical perspectives and emerging models of inter-American studies

Abstract

Alfred Hitchcock’s Rear Window (1954) has been the subject of much critical attention, but the original story upon which it was based and its author, Cornell Woolrich, less so. This article examines ‘Rear Window’ (1942) in the context of Woolrich’s writing and his life more broadly, in order to reveal the privileged role of fenestral imagery in his work. Through a process which starts with surveillance through glass, and a creative interpretation of ‘real’ events consumed in terms strikingly similar to mass media entertainments, Woolrich’s marginalized protagonist assumes the role of the detective and, in doing so, his identity is enhanced. The Woolrichian window reifies abstract social boundaries. It serves, simultaneously, as a symbol of urban alienation and a fantasy of social integration. It also becomes a trope of consumption and popular culture. Hitchcock’s film has sometimes been praised for the self-conscious way in which it aligns the image of the window with the cinema screen in order to implicate viewers in the protagonist’s voyeuristic practice. This article extends such an analysis to Woolrich’s story, but also takes it a step further, to reveal the ways in which reading similarly might be regarded as a voyeuristic form of cultural consumption.     

光纤Bragg光栅全光调谐滤波器

针对非线性特性对光纤布拉格光栅禁带的影响进行了研究;对光栅在非线性作用下所呈现的Bragg波长偏移特性作了理论分析。仿真结果表明,随着输入信号功率的增大,光栅的布拉格波长向长波方向移动,反射峰值下降,反射带宽变窄。基于此原理提出了一种新的全光可调谐滤波方案,并对不同光栅参数下的输出波形和反射谱特性进行了比较。该方案通过控制光实现了对光纤布拉格光栅固有波长的调节,从而实现了全光可调谐滤波,仿真结果表明脉冲形状保持良好。     

分布式光纤传感器的原理及发展

从光时域反射仪（OTDR）的原理入手,介绍了分布式光纤传感器的当前进展及发展趋势,主要包括基于瑞丽后向散射的传感器,基于布里渊散射的分布式光纤传感器,基于拉曼后向散射的温度传感器,以及偏振模耦合分布式光纤传感器。对其特点及存在的问题进行了比较,并指出了未来发展方向。     

导电纤维在抗静电面料中应用的研究

本文综述了导电纤维的发展状况，并对日本工作服面料进行了测试分析，重点讨论了导电纤维在消除静电方面的应用，提出了产品开发的方向.     

W-OCDMA系统中MPC/OOC二维码的构造及实现

基于光正交跳频码构造原理,分别用改进素数码和光正交码为时域扩频模式和频域跳频模式,并构造了适用于无线光码分多址系统的调整数码/光正交码二维组合码。和现有二维码相比,该组合码容量大,通过有规律的分组,每组内码字具有良好的相关性,同时组内具有较大的码容量。该构造方式易于实现,对构造实例设计了可调谐光纤布拉格光栅编解码器。     

阶跃型红外光纤色散的理论研究

本文从理论上研究了阶跃型折射率分布氟玻璃圆光纤的色散特性.通过大量计算,找到了几种最佳结构,这些结构可把零色散波长推展到2～5μm之间,而已经证明,氟玻璃光纤在2～5μm的损耗降低到0.001～0.1dB/km,从而达到了零色散波长和最低级限损耗波长相匹配的目的.同时,比较了各种ZrF4系红外材料的色散曲线,得出了零色散和阶跃型折射率分布氟玻璃单模光纤的光谱范围,并且得到了在三个波长处总色散为零的结论.     

掺铒光纤放大器增益的温度依赖关系

报道掺铒光纤放大器增益随温度变化的依赖关系，提出了一个解释这种依赖关系的数学模型。此模型基于如下假设；由于温度的变化，引起处在基态和激发态的斯塔克（Stark)能级上的掺铒离子（Er^3 )浓度的重新分布，从而引发光纤发射截面和吸收截面的变化，理论结果与实验结果符合很好。