Fiber in-line magnetic field sensor based on Mach-Zehnder interferometer integrated with magnetic fluid

In this paper, magnetic fluid (MF), a new type of optical functional nanomaterial with interesting optical characteristics under the external magnetic field, is adopted to form a novel fiber-optic magnetic field sensor. The proposed sensor is based on Mach-Zehnder interferometer (MZI) and has a multimode-singlemode-multimode (MSM) fiber structure. The MSM structure was fabricated by splicing a section of uncoated single mode fiber (SMF) between two short sections of multimode fibers (MMFs) using a fiber fusion splicer. The magnetic field sensing probe was made by inserting the fiber-optic structure in an MF-filled capillary tube. Variations in an external magnetic field is seen to cause changes in the refractive index of MF. This tunable change in the refractive index with magnetic field strengths between 0.6 mT to 21.4 mT produces a shift in the peak position of the wavelength. The shift of the valley wavelength with magnetic field intensity has a good linearity of up to 99.6%. The achieved sensitivity of the proposed magnetic field sensor is 0.123 nm/mT,which is improved by several folds compared with those of most of the other reported MF-based magnetic field sensors. Furthermore, we build the corresponding circuit-based measurement system, and the experimental results show that the voltage change indirectly reflects the change of the external magnetic field strength. Therefore, this provides the potential to fiber-based magnetic field sensing applications.     

高校辅导员践行群众路线过程中的几点思考

高校辅导员作为学生思想政治工作的一线承担者,工作的有效性关系到班级活动的顺利开展和学生身心的全面发展。文中对高校辅导员与学生关系、如何构建和谐的师生关系,及践行群众路线作为高校辅导员开展学生工作的思路和方法进行了介绍。     

提高重油催化裂化装置经济效益的措施

以装置经济效益最大化为目的，建立了数学分析模型，并结合大港石化公司的实际状况对不同的生产工艺(如干气预提升、终止剂技术、稳定汽油回炼等)、操作条件(如反应温度、催化剂类型等)进行了统计分析，讨论了这些方案对产品分布和经济效益的影响。同时，以大量生产数据为基础，找出了平衡剂上Ni含量和Sb/Ni与催化剂活性的关系，以及平衡剂活性对转化率和各催化产品分布的影响，从而最终确定出装置经济效益最大化数学模型。讨论了当原料油性质、石油产品市场、新鲜催化剂价格变化时，新鲜催化剂补充速率的调整方案。     

基于尖峰能量谱技术的滚动轴承故障分析

介绍振动尖峰能量谱（Spike Energy Spectrum）技术用于滚动轴承故障的分析方法、原理、测量要求，以及该种技术的成功应用情况，总结出故障诊断中的一些实用技巧。     

基于Agent的种植业比较优势协同分析系统的研究

针对目前已有的区域比较优势分析系统缺乏对各种资源进行分析并进一步进行种植业结构规划和调整能力的问题,本文着重探讨如何综合运用系统科学、人工智能、软件工程与模型设计的知识,构建更加完善的种植业比较优势协同分析系统。系统充分利用了Agent的技术特点,采用协同分析的方法,实现了多个可重用的Agent子系统,并为整合已有相关比较优势系统提供了接口,为传统种植业区域比较优势研究提供了一种可借鉴的新思路。