Those conclusions may be meaningful for us to determine mixture ratio when fabricating composite films with special structures . 2 . we study the phase - separation and microstructure of the pure binary and trinary mixed lb and ls films of dimyristoyl phosphatidyicholine ( dmpc ) cholesterol ( chol ) and sphingomylin ( sph ) deposited from pure water subphase by - a isotherms and tapping mode atomic force microscopy 2 、利用- a等温曲线和原子力显微镜的轻敲模式对从纯水亚相上提拉的不同生物分子二肉豆蔻酰磷脂酰胆碱( dmpc ) 、胆固醇( chol . )和神经鞘磷脂( sph )不同种纯的、二元及三元混合单分子膜- lb膜和ls膜体系的相分离和微结构进行了研究。
The paper lays a strong emphasis on discussing the realization of the autocontrol of raster scanning of the scanner in x - y dimension , the " tapping " of the cantilever of the tappingmode afm by a direct digital synthesizer . then a method of parallel communication between dsp and pc in epp mode is given . finally , the author discussed the digital pid closed loop control of the scanner in z - direction , the automatic approaching of the tip using step - motor , and also some electro - magnetic interferences 论文首先简单介绍了扫描探针显微镜的发展、分类、工作原理及应用；接着对ti公司的tms320vc5402dsp的特点及外围扩展作了简单介绍；然后分章节重点讲述了利用vc5402dsp实现扫描探针显微镜的核心部件? ?压电陶瓷管的x向和y向的光栅扫描控制；借助直接数字集成器( dds )实现轻敲式原子力显微镜的微悬臂的“轻敲” ； vc5402dsp的主机接口( hpi )与pc机在增强并行口( epp )模式下的通信；论文最后还介绍了扫描管z向的数字pid闭环控制，步进电机的自动进针，并对实际出现的一些电磁干扰问题作了讨论。
