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为解决某矿主采煤层瓦斯含量高、工作面瓦斯浓度高等制约矿井安全高效生产的问题,根据煤层瓦斯参数及赋存情况,采用回采巷道边掘边抽及顺层钻孔预抽回采区域煤层瓦斯措施,并对回采工作面瓦斯预抽效果及评价指标进行分析。 相似文献
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选择性催化还原(SCR)技术广泛被应用于燃煤电厂NOx减排,而SCR脱硝技术对颗粒物(PM)的影响尚不清楚。在两台300 MW煤粉锅炉机组SCR反应器的入口和出口进行了颗粒物现场采样,分析了SCR脱硝过程对PM的质量粒径分布和痕量元素含量的影响。研究结果显示,SCR脱硝过程产生NH+4,SO2+4等组分并部分转化为颗粒物,促使0.1 μm以下颗粒物团聚、长大,导致0.3 μm以下颗粒物的峰值粒径由0.1 μm增大到0.3 μm,同时使S含量显著升高,最终导致0.3 μm以下颗粒物浓度升高约30.67%。烟气中部分0.3 μm以上颗粒物在SCR反应器中受惯性碰撞作用而分离,使其浓度降低0.06%~33.11%,但峰值粒径和组成成分不变。SCR反应器入口烟气中的气态痕量元素在脱硝过程中向颗粒物转移,引起PM中痕量元素含量变化。实验条件下,经过SCR反应器后,0.3 μm以下颗粒物中Cd,As,Pb含量分别升高104.15%,12.26%和12.18%,而Cr含量降低23.38%;0.3 μm以上颗粒物中各痕量元素含量均略有升高。 相似文献
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输电线路覆冰图像边缘提取方法研究 总被引:3,自引:3,他引:3
A new method of measuring the icing thickness of transmission lines on-line is proposed in this paper.In this method,the pictures of transmission lines which are photoed by the camera on the iron tower are processed immediately to extract the edges of the transmission line conductor and transmission line insulators.The icing thickness can be gained by comparing the edges of the iced transmission line and the uniced one.Two icing image edge extraction methods are described in detail,that is,a method based on the combination of the wavelet transform and the floating threshold method and a method based on the combination of the optimal threshold method and the mathematical morphology transform.The icing images from the artificial climatic chamber and transmission lines are used to test the methods above.The results show that the method based on the wavelet transform and the floating threshold method does well in the extraction of relatively smooth edges,such as glaze icing on conductor and icing on the insulator;meanwhile,the method based on the optimal threshold method and the mathematical morphology transform does well in the edge extraction of icing on the conductor,especially the opaque rime icing on the conductor with complicated edges. 相似文献
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随着移动终端设备的应用,人们对网络传输的速度提出了更高的要求,移动通信网络如果提高通信传输效率,保证网络的稳定性与可靠性,成为移动通信网络需要解决的关键问题。EPON网络技术作为一种新兴的网络技术,为用户提高了足够的网络通信速率,也解决了网络数据的安全性,通过对EPON网络技术的内涵与特点进行分析,指出了EPON技术在移动通信中的优势,为用户提供了多元化的服务,并分析了EPON技术的工作原理与关键网络结构,探究了EPON技术在移动通信需要注意的问题。 相似文献
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