DDME分子在石墨(HOPG)表面吸附

用扫描隧道显微镜(STM)研究了用真空沉积法在高定向有序石墨(HOPG)上制备的1, 1dicyano-2, 2-(4-dimethylaminophenyl) ethylene(DDME)薄膜。DDME在石墨表面形成十分平整的分子柱状堆积二维有序结构。还观察到了随覆盖度降低转变成为其他二维有序结构,并对其形成机理进行了研究。     

色氨酸分子在石墨表面吸附的扫描隧道显微镜研究

用扫描隧道显微镜(STM)研究了室温下色氨酸分子(L-Tryptophane)在石墨(HOPG)表面的吸附行为。实验发现,在室温下色氨酸分子可以在石墨表面形成均匀的吸附层,并形成二维条状结构和二维单斜晶格两种有序结构。针对这2种结构给出了可能的吸附模型。这2种有序结构的形成原因被认为与相邻色氨酸分子侧链之间的π堆积相互作用有关。     

用STM在石墨晶体表面进行纳米级加工

中国科学院化学研究所扫描隧道显微学研究室用自己研制的扫描隧道显微镜(STM)在石墨晶体表面进行纳米级加工,由计算机控制刻写出线条宽约10纳米的字符和图案,并用STM获得加工后的图像。     

DNA分子在云母表面拉直技术的研究

对DNA分子的生物、物理和化学性质的很多研究,都要求对单个DNA分子的性质进行深入探索,实现DNA分子在基底表面上的拉直是对其深入研究的物理基础。文章在APS溶液处理过的云母片表面,通过不同的方法完成了对DNA分子的拉直操作,利用原予力显微镜对拉直后的DNA分子进行了表征,获得了DNA分子拉直后的形貌,并对每种拉直方法进行了比较和讨论。     

DNA电性能测定方法以及DNA分子器件的研究进展

DNA分子不仅能够定义生命机体的基因代码,而且在生命科学领域以外,尤其是纳米技术领域中发挥着重要的作用.关于DNA分子的导电性,目前存在争议.文中在大量文献的基础上,试图对DNA分子导电性的研究现状和测定方法进行较详尽的评述,并对电荷在DNA内的可能迁移机制做简要的介绍.此外,基于DNA分子或以DNA分子为模板的分子器件是当前国际的一个研究热点,文中对DNA分子器件的研究现状进行了总结,并对其应用前景进行了预测.     

DNA电性能测定方法以及DNA分子器件的研究进展

DNA分子不仅能够定义生命机体的基因代码，而且在生命科学领域以外，尤其是纳米技术领域中发挥着重要的作用．关于DNA分子的导电性，目前存在争议．文中在大量文献的基础上，试图对DNA分子导电性的研究现状和测定方法进行较详尽的评述，并对电荷在DNA内的可能迁移机制做简要的介绍．此外，基于DNA分子或以DNA分子为模板的分子器件是当前国际的一个研究热点，文中对DNA分子器件的研究现状进行了总结，并对其应用前景进行了预测．     

碳纳米管的STM观测

本文利用隧道扫描显微镜（STM）在室温条件下，低真空环境中，在高定向裂解石墨（HOPG）表面，对单壁碳纳米管（SWCN）以及多壁碳纳米管（MWCN）进行了观测，效果良好。     

扫描隧道显微镜对碳颗粒形貌的研究

通过用电化学腐蚀法制作针尖以及制备碳颗粒和高温定向热解石墨样品,利用STM研究高温定向热解石墨和碳颗粒的结构特征及其形貌,通过热解石墨六角型结构碳原子间距对系统定标,可估测碳颗粒的尺度。     

温度对石墨平面吸附水环境中甲烷分子过程的影响

为研究温度对甲烷分子在水-石墨界面上吸附的影响,利用分子动力学模拟,分析了不同温度下多层石墨平面对水环境中甲烷分子的吸附情况.结果表明:石墨平面片层吸附甲烷分子时呈现出特定的吸附位点,甲烷分子沿这些吸附位点呈六边形状态聚集,且吸附在石墨平面上的甲烷分子有序分层,第1层吸附饱和后将在吸附位点附近继续第2层吸附.进一步分析发现,在等容体系中,石墨平面吸附甲烷量与温度呈近似线性关系,且温度越高吸附总量反而越大.这些研究结果对理解疏水固体表面吸附水环境中气体分子的微观机制有所帮助.     

DNA分子的弹性及环境因素的影响

首先阐述了DNA分子结构的多态性，介绍了DNA分子弹性的研究进展以及外界环境的影响，最后对DNA分子的研究前景进行了展望．     

Atomic-scale imaging of DNA using scanning tunnelling microscopy

The scanning tunnelling microscope (STM) has been used to visualize DNA under water, under oil and in air. Images of single-stranded DNA have shown that submolecular resolution is possible. Here we describe atomic-resolution imaging of duplex DNA. Topographic STM images of uncoated duplex DNA on a graphite substrate obtained in ultra-high vacuum are presented that show double-helical structure, base pairs, and atomic-scale substructure. Experimental STM profiles show excellent correlation with atomic contours of the van der Waals surface of A-form DNA derived from X-ray crystallography. A comparison of variations in the barrier to quantum mechanical tunnelling (barrier-height) with atomic-scale topography shows correlation over the phosphate-sugar backbone but anticorrelation over the base pairs. This relationship may be due to the different chemical characteristics of parts of the molecule. Further investigation of this phenomenon should lead to a better understanding of the physics of imaging adsorbates with the STM and may prove useful in sequencing DNA. The improved resolution compared with previously published STM images of DNA may be attributable to ultra-high vacuum, high data-pixel density, slow scan rate, a fortuitously clean and sharp tip and/or a relatively dilute and extremely clean sample solution. This work demonstrates the potential of the STM for characterization of large biomolecular structures, but additional development will be required to make such high resolution imaging of DNA and other large molecules routine.     

Self-assembly of 4-（amyloxy） cinnamic acid on HOPG and its photoinduced transformation： An STM study

With the development of the nanoscience and nanotechnology, scientists try to use single molecule to fabricate electronic device, and the so-called “bot- tom-up” technology was considered to be one of the effective methods, which constructs molecular el…     

扫描隧道显微镜应用于生物超微结构探测的机制

在利用扫描隧道显微镜研究质位pUC18DNA分子线圈型超螺旋拓扑结构的基础上，进一步探讨了扫描隧道显微镜应用于生物超微结构探测的可能机制，并指出扫描隧道显微镜技术是探测生物超微结构，尤其是DNA拓扑结构的较好手段。     

Study of-amyloid adsorption and aggregation on graphite by STM and AFM

Alzheimers disease is the major cause of dementia and the fourth leading cause of death in the developed world after heart disease, cancer and stroke. Pathologi-cally, one of major hallmarks of Alzheimers disease is the formation of insoluble deposits of -amyloid (A) both as diffuse and senile plaques in the brain tissue. The plaques are fibrous masses composed primarily of the 40-42 resi-due A peptides. The two most abundant forms of A are, respectively, the 40 and 42 residue peptide -amylo…     

Study of β—amyloid adsorption and aggregation on graphite by STM and AFM

The scanning tunneling microscopy(STM) and the atomic force microscopy(AMF) have been applied to the direct study of the adsorption and aggregation of β-amyloid(1-42)(Aβ42)on the hydrophobic graphite surface.It was found that Aβ42 were preferentially adsorbed on graphite defects such as the edges.Aβ42 peptides self-assembled into intermediate protofibrils,which in turn self-associated to form fibrils.Usually,two or more fibrils intertwined to form the helical structure.These results will provide an important clue to studying the aggregation process of β-amyloid.     

Direct observation of monomer film structure of bacteriochlorophyll c

The adsorption and assembling of bacteriochlorophyll c (BChl c) on a highly oriented pyrolytic graphite (HOPG) surface have been investigated by the scanning tunneling microscopy (STM). BChl c molecules are found to self-organize a well-defined adlayer on HOPG surface with a monomeric structure different from the dimer association seen on adlayers of Chls a, c and BChlide c, d. A structural model is proposed for the adlayer.     

2D self-assembling of 4, 5-didodecylthiolphthalonitrile on graphite surface

An important precursor 4,5-didodecylthiolphthalonitrile (DCP) for synthesis of phthalocyanines (Pcs) and subphthalocyanines (SubPcs) was synthesized and the assembling structure of this molecule on the basal plane of highly oriented pyrolytic graphite (HOPG) surface was characterized using the scanning tunneling microscopy (STM) in ambient conditions. In high-resolution images of the molecules, we found that the arrangement of the cyano groups forms a “head-to-head” configuration to keep the stability of the entire system. The mismatch of the DCP molecules with the substrate lattice has also been observed in the experiment.     

扫描方向对STM图像的影响

利用Ｗｉｎｄｏｗｓ的ＧＤＩ位图和ＤＩＢ位图,用Ｍｉｃｒｏｓｏｆｔ Ｖｉｓｕａｌ Ｃ＋＋６．０编制了扫描驱动以及能够同时显示和存储多幅伪彩色图像的程序,并用该程序对高定向石墨进行了原子量级和纳米量级的成像。实验观测到对同一样品同一区域,如果扫描方向不同,得到的图像也不同,本文根据ＳＴＭ的反馈成像机理对此进行了解释。