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2009 1

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LMS 1

单波束测距 1

微地形测距 1

海底钴结壳 1

自适应滤波法 1

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Atomic force microscopy study on the microtopography of natural organic matter and newly formed hydrous

GUO Jin, MA Jun, SHI Xuehua

《环境科学与工程前沿（英文）》 2007年第1卷第2期页码 251-256 doi: 10.1007/s11783-007-0043-z

摘要： To understand the water purification mechanism of potassium permanganate as a coagulation-aid during the preoxidation process, the microtopography of its reductive products, the newly formed hydrous manganese dioxide and the aged hydrous manganese dioxide, was investigated. The morphology of natural organic matter (NOM) adsorbed by the newly formed hydrous manganese dioxide was also compared with that of NOM alone. By using the tapping mode atomic force microscopy (AFM), the observation results show that the newly formed hydrous manganese dioxide possess a perforated sheet (with a thickness of 0 1.75 nm) as well as some spherical particle structures compared with the hydrous manganese dioxide with 2 h aging time, which demonstrated that the newly formed hydrous manganese dioxide had a large surface area and adsorption capacity. When 1 mmol/L newly formed hydrous manganese dioxide was added, the microtopography of NOM molecules shifted from a loosely dispersed pancake shape (with adsorption height of 5 8.5 nm) to a densely dispersed and uniform spherical structure. These results provide a valid proof that it is the perfect adsorption capability of the newly formed hydrous manganese dioxide that might result in the coagulation aid effect of potassium permanganate preoxidation.

关键词： spherical microtopography potassium permanganate uniform spherical morphology

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基于LMS自适应时延估计法的微地形测距系统研究

刘爱军,周知进,卜英勇,龙迎春

《中国工程科学》 2009年第11卷第8期页码 79-82

摘要：

根据单波束超声波测距原理，向模拟海底钴结壳微地形的水池表面发射超声波，应用自适应滤波方法可以估计超声回波信号的时延，使最小均方误差（LMS）后的回波信号与参考信号之间方差达到最小值，此刻的延时量就是渡越时间t，从而求出探头与目标之间的距离。通过计算机仿真和试验结果表明,将最小均方误差自适应时延法应用于海底微地形高程数据的测量,获得测距精度高，能够适用于海底微地形的探测。

关键词：海底钴结壳微地形测距 LMS 单波束测距自适应滤波法