In the purple hilly region, erosions and landslides are all serious, and it is of great scientific value and practical significance to study their formation mechanism and distribution features there. In this paper, so...In the purple hilly region, erosions and landslides are all serious, and it is of great scientific value and practical significance to study their formation mechanism and distribution features there. In this paper, soil micromorphological methods and techniques were used to study the erosion zonal distribution in the region. The results indicated: (1) According to erosion process, the spacial distribution zones of the erosions and landslides in the purple hilly region with different solums were divided into scouring erosion zone, transport-diffusion zone, rocks and soil turbulence zone and sediment-bury zone; (2) The soil micromorphologic taxonomic feature identifying different erosion-landslide zone were found by studying the soil micromorphology of erosive zone in purple hilly region; (3) As for the erosion–landslide formation in the region, besides the external factors, the internal factors were found more important and favorable for landslide formation through the studies on the micormorphological features of slide soil.展开更多
An electrostatic micromotor is compared with a conventional electromagnetic mieromotor, and the scaling effect of driving forces is analysed according to their different operation principles. Characteristic dimension ...An electrostatic micromotor is compared with a conventional electromagnetic mieromotor, and the scaling effect of driving forces is analysed according to their different operation principles. Characteristic dimension L represents the linear scale of micromotors. Electromagnetic driving force is proportional to high-order power of characteristic dimension L whereas electrostatic driving force is not. So, in micro domain, the effect of electrostatic force is larger than that of electromagnetic force, which makes electrostatic micromotor more competitive against electromagnetic alternative in MEMS. In assessing the performance of a micromotor, the power per unit volume and efficiency are the two most important criteria. Hence, the two kinds of micromotors are further compared from these two aspects. The results indicate that electrostatic a micromotor has higher power per unit volume and efficiency, moreover, its structure is simple, it can be made sufficiently small. For those advantages of electrostatic micromotors, they can be used in optical devices, aerospace equipment and medical instruments.展开更多
基金supported by the Knowledge Innovation Project of the Chinese Academy of Sciences(KZCX3-SW-330)the State Natural Science Foundation for Outstanding Personnel of China(40025103)
文摘In the purple hilly region, erosions and landslides are all serious, and it is of great scientific value and practical significance to study their formation mechanism and distribution features there. In this paper, soil micromorphological methods and techniques were used to study the erosion zonal distribution in the region. The results indicated: (1) According to erosion process, the spacial distribution zones of the erosions and landslides in the purple hilly region with different solums were divided into scouring erosion zone, transport-diffusion zone, rocks and soil turbulence zone and sediment-bury zone; (2) The soil micromorphologic taxonomic feature identifying different erosion-landslide zone were found by studying the soil micromorphology of erosive zone in purple hilly region; (3) As for the erosion–landslide formation in the region, besides the external factors, the internal factors were found more important and favorable for landslide formation through the studies on the micormorphological features of slide soil.
文摘An electrostatic micromotor is compared with a conventional electromagnetic mieromotor, and the scaling effect of driving forces is analysed according to their different operation principles. Characteristic dimension L represents the linear scale of micromotors. Electromagnetic driving force is proportional to high-order power of characteristic dimension L whereas electrostatic driving force is not. So, in micro domain, the effect of electrostatic force is larger than that of electromagnetic force, which makes electrostatic micromotor more competitive against electromagnetic alternative in MEMS. In assessing the performance of a micromotor, the power per unit volume and efficiency are the two most important criteria. Hence, the two kinds of micromotors are further compared from these two aspects. The results indicate that electrostatic a micromotor has higher power per unit volume and efficiency, moreover, its structure is simple, it can be made sufficiently small. For those advantages of electrostatic micromotors, they can be used in optical devices, aerospace equipment and medical instruments.