Three-dimensional atomic force microscopy

Figure 8.2 Three-dimensional atomic force microscopy images of the surface of (a) uncoated, (b) single-layered, (c) double-layered, and (d) triple-layered coated samples, (e) roughness values of the deposited Hlms. ...

Figure 1.8 Example of mold characterization by three-dimensional atomic force microscopy (AFM3D) (lOOnm wide lines).

T. Fukuma, Y. Ueda, S. Yoshioka, and H. Asakawa, Atomic-scale distribution of water molecules at the mica-water interface visualized by three-dimensional scanning force microscopy, Phys. Rev. Lett. 104, 016101 (20103. 

Although experimental studies of DNA and RNA structure have revealed the significant structural diversity of oligonucleotides, there are limitations to these approaches. X-ray crystallographic structures are limited to relatively small DNA duplexes, and the crystal lattice can impact the three-dimensional conformation [4]. NMR-based structural studies allow for the determination of structures in solution however, the limited amount of nuclear overhauser effect (NOE) data between nonadjacent stacked basepairs makes the determination of the overall structure of DNA difficult [5]. In addition, nanotechnology-based experiments, such as the use of optical tweezers and atomic force microscopy [6], have revealed that the forces required to distort DNA are relatively small, consistent with the structural heterogeneity observed in both DNA and RNA. 

Figure 10. Three-dimensional AFM images of (a) Pt/polished AI2O3, (b) Pt/etched Ni, and (c) Pt/unpolished AI2O3 electrodes. Reprinted from J. -Y. Go et al., A study on ionic diffusion towards self-affine fractal electrode by cyclic voltammetry and atomic force microscopy, J. Electroanal. Chem., 549, p. 49, Copyright 2003, with permission from Elsevier Science.

Hizume K, Yoshimura SH, Maruyama H, Kim J, Wada H, Takeyasu K (2002) Chromatin reconstitution development of a salt-dialysis method monitored by nano-technology. Arch Histol Cytol 65 405 13 Hizume K, Yoshimura SH, Takeyasu K (2004) Atomic force microscopy demonstrates a critical role of DNA superhelicity in nucleosome dynamics. Cell Biochem Biophys 40 249—262 Hizume K, Yoshimura SH, Takeyasu K (2005) Linker histone HI per se can induce three-dimensional folding of chromatin fiber. Biochemistry 44 12978-12989 Hofmann WA, de Lanerolle P (2006) Nuclear actin to polymerize or not to polymerize. J Cell Biol 172 495-496... 

Fig. 116a. Three-dimensional side view of a PbSe particulate film imaged on a 470 nm x 470 nm section by atomic force microscopy (AFM). b Profile of the PbSe crystals by AFM sectioning. The vertical tine in the image shows the position of the sectioning [648]...

In atomic force microscopy (AFM), the sharp tip of a microscopic probe attached to a flexible cantilever is drawn across an uneven surface such as a membrane (Fig. 1). Electrostatic and van der Waals interactions between the tip and the sample produce a force that moves the probe up and down (in the z dimension) as it encounters hills and valleys in the sample. A laser beam reflected from the cantilever detects motions of as little as 1 A. In one type of atomic force microscope, the force on the probe is held constant (relative to a standard force, on the order of piconewtons) by a feedback circuit that causes the platform holding the sample to rise or fall to keep the force constant. A series of scans in the x and y dimensions (the plane of the membrane) yields a three-dimensional contour map of the surface with resolution near the atomic scale—0.1 nm in the vertical dimension, 0.5 to 1.0 nm in the lateral dimensions. The membrane rafts shown in Figure ll-20b were visualized by this technique. 

Atomic force microscopy 131,179, 392 Atomic structures of macromolecules. See Three-dimensional structures... 

SEM, as others surface-based methods such as scanning probe microscopy (SPM), or more specifically atomic force microscopy (AFM), generally only shows the surface or a cross-section of the three-dimensional arrangement of the CNTs in the polymer matrix. However, the team of Loos et al. has shown that conventional SEM is able to provide (pseudo) three-dimensional morphological... 

Several different gelation measurement methods have been described in the literature, particularly differential scanning calorimetry (DSC), capillary rheometry, transmission electron microscopy (TEM) and atomic force microscopy (AFM). The gelation level is characterised either by crystallinity related aspects or factors that relate to the development of the three-dimensional network and the corresponding disappearance of the particulate structure (465, a.l). 

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