Experimental Research on Erbium-doped Superfluorescent Fiber Source

The effects of the variations in fiber length, fiber mirror reflectance on efficiency and output power are experimentally investigated for erbium-doped double pass backward superfluorescent fiber sources (SFSs). The influence of fiber length on mean wavelength stability (MWS) has also been demonstrated. By incorporating a short section of un-pumped erbium-doped fiber (EDF) at the output port, the pump power dependent on MWS becomes independent of pumped EDF length. This is a novel phenomenon that hasn‘t been reported up to now,and should be helpful to SFS fabrication and theory analysis. By using a fiber Michelson interferometer as spectrum slicing component,a multi-wavelength fiber source (MWFS) with ～20 channels (from 1542nm to 1559nm) is got. The MWFS has a channel spacing of ～0. 8 nm which satisfies ITUstandard. The intensity fluctuation among channels is less than 0.5dB,and the extinction ratio of all channels is above 14dB. This kind of MWFS should be useful to wavelength division multiplexing systems.     

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今年汛期永年县在确保安全度汛的前提下，按照“防汛抗旱科学化、雨洪利用资源化”的思路，抢抓后汛期集蓄雨水的黄金时机，充分发挥水利工程调蓄功能，千方百计拦蓄地表水，截至目前，累计蓄水600万m^3。     

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54室焙烧炉技术改造实践

通过技术改造,54室焙烧炉各项经济技术指标显著提高,取得了较好的社会、经济效益。     

40kg试验焦炉的研制

文章介绍了40kg试验焦炉，分析和比较了试验焦炉与生产焦炉的差异，指出它们之间的模拟条件是炭化室宽度、煤料堆密度、炼焦速度和单向传热。     

烟化炉工艺设备的三项技术改进措施

详细介绍了烟化炉工艺设备在生产实践中暴露出的问题，分析了事故原因及采取的技改措施，消除了安全隐患，提高了炉子的作业率，并获得较好的经济效益。     

异型旅游梁抽油机后驴头连接套的焊接与加工

异型游梁抽动机与常规游梁抽油机相比，前者在结构上增设了后驴头钢绳软连接。后头与游梁的连接是否可靠是该型机的重要质量保证之一。采用在连接套上增设圆挡环的方案，将连接套内孔焊接变形的问题转移到前道工序之前和圆挡环外圆上，从而提高了连接套的形位精度。用新方案焊接后，销轴与连接套内孔的配合间隙最大为＋０．４ｍｍ，最小为＋０．１７ｍｍ，大大提高了装配质量，标准公差等级由原ＩＴ１２级提高到ＩＴ１０级。