Initial Graphite Disorder of Carbon Lattice Structures Increase Surface Hydrophilicity and Protein Adsorption

Surface microgrooves and acid etching on titanium (Ti) have been proposed to enhance various cell behaviors. In this study, surface hydrophilicity, protein adsorption, and alkaline phosphatase activity of osteoblasts were analyzed and compared between microgrooved Ti, Ti with microgrooves and further acid etching, smooth Ti, and acid-etched smooth Ti. Correlations between the results of each experiment were analyzed using Pearson's correlation analysis, and the influential factor on alkaline phosphatase activity was determined using multiple stepwise regression analysis. Among groups, the Ti substrata with microgrooves and subsequent acid etching showed significantly greater surface hydrophilicity and alkaline phosphatase activity compared with smooth Ti, whereas the Ti substrata with only microgrooves showed the greatest protein adsorption. Multiple stepwise regression analysis determined the surface hydrophilicity of Ti as the influential factor on alkaline phosphatase activity. This study indicates that surface microgrooves and acid etching on Ti substrata enhance surface hydrophilicity, leading to increased alkaline phosphatase activity.

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Backscattered Electron Imaging of GaAs/AlGaAs Super Lattice Structures with an Ultra-High- Resolution SEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100103103 ◽

1988 ◽

Vol 46 ◽

pp. 204-205

Author(s):

Kazumichi Ogura ◽

Michael M. Kersker

Keyword(s):

High Resolution ◽

Layer Structure ◽

High Sensitivity ◽

Beam Current ◽

Electron Beam Current ◽

Lattice Structures ◽

Super Lattice ◽

Different Types ◽

Backscattered Electron ◽

Electron Imaging

Backscattered electron (BE) images of GaAs/AlGaAs super lattice structures were observed with an ultra high resolution (UHR) SEM JSM-890 with an ultra high sensitivity BE detector. Three different types of super lattice structures of GaAs/AlGaAs were examined. Each GaAs/AlGaAs wafer was cleaved by a razor after it was heated for approximately 1 minute and its crosssectional plane was observed.First, a multi-layer structure of GaAs (100nm)/AlGaAs (lOOnm) where A1 content was successively changed from 0.4 to 0.03 was observed. Figures 1 (a) and (b) are BE images taken at an accelerating voltage of 15kV with an electron beam current of 20pA. Figure 1 (c) is a sketch of this multi-layer structure corresponding to the BE images. The various layers are clearly observed. The differences in A1 content between A1 0.35 Ga 0.65 As, A1 0.4 Ga 0.6 As, and A1 0.31 Ga 0.69 As were clearly observed in the contrast of the BE image.

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Lattice imaging of precipitates in Al-Zn-Mg alloy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100143651 ◽

1986 ◽

Vol 44 ◽

pp. 412-413

Author(s):

C. K. Wu

Keyword(s):

Grain Boundaries ◽

Homogeneous Nucleation ◽

Alloy System ◽

Mg Alloy ◽

List Type ◽

Lattice Structures ◽

Type Number ◽

Orientation Relationships ◽

Lattice Imaging ◽

The Matrix

The precipitation phenomenon in Al-Zn-Mg alloy is quite interesting and complicated and can be described in the following categories:(i) heterogeneous nucleation at grain boundaries;(ii) precipitate-free-zones (PFZ) adjacent to the grain boundaries;(iii) homogeneous nucleation of snherical G.P. zones, n' and n phases inside the grains. The spherical G.P. zones are coherent with the matrix, whereas the n' and n phases are incoherent. It is noticed that n' and n phases exhibit plate-like morpholoay with several orientation relationship with the matrix. The high resolution lattice imaging techninue of TEM is then applied to study precipitates in this alloy system. It reveals the characteristics of lattice structures of each phase and the orientation relationships with the matrix.

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