Photochemical Dissociation of Organic Silicon Source using Xe2 Excimer Lamp in Gas Phase.

The organic-silicon films, polytetrafluorethylene (PTFE) films and its composite films with copper have been fabricated from an active gas phase by pulse laser dispersion from initial powder species. The features of all films obtained were studied with the application of attenuated total reﬂection-Fourier transform infrared (ATR-FTIR) spectroscopy. Our results suggest that the wavelength of laser radiation impact a strong effect on the molecular structure of all films. Specifically, the peaks corresponding to the detachment of C-H bonds in the organic-silicon films and its Cu doped films at a laser wavelength of 532 nm and the destruction of the Si-O-Si groups at 266 nm due to the ultraviolet radiation have been observed. Interestingly, the concentration of Si-С6Н5 groups relative increases with a decremental of the wavelength of laser radiation. In addition, the PTFE films formed at a laser wavelength of 355 nm presented a lower order degree and high amorphous phase, while PTFE-Cu composite films at laser wavelength 266 nm exhibited enhanced crystallinity due to the presence of copper species, wherein being served as nucleation centers. Remarkably, the wavelengths of laser radiation nearly play no effect on the orderness of PTFE-Cu composite films.

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Residual Gas Reactions in the Electron Microscope: I. Qualitative Observations on the Water Gas Reaction

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100101207 ◽

1968 ◽

Vol 26 ◽

pp. 292-293

Author(s):

Richard E. Hartman ◽

Roberta S. Hartman ◽

Peter L. Ramos

Keyword(s):

Electron Beam ◽

Electron Microscope ◽

Gas Phase ◽

Absolute Temperature ◽

Residual Gas ◽

Gas Reactions ◽

Image Position ◽

The Right ◽

Water Gas ◽

Thinning Rate

The action of water and the electron beam on organic specimens in the electron microscope results in the removal of oxidizable material (primarily hydrogen and carbon) by reactions similar to the water gas reaction .which has the form:The energy required to force the reaction to the right is supplied by the interaction of the electron beam with the specimen.The mass of water striking the specimen is given by:where u = gH2O/cm2 sec, PH2O = partial pressure of water in Torr, & T = absolute temperature of the gas phase. If it is assumed that mass is removed from the specimen by a reaction approximated by (1) and that the specimen is uniformly thinned by the reaction, then the thinning rate in A/ min iswhere x = thickness of the specimen in A, t = time in minutes, & E = efficiency (the fraction of the water striking the specimen which reacts with it).

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Integration of Core-Edge Spectroscopy Methods for the Study of Polymers

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010016323x ◽

1996 ◽

Vol 54 ◽

pp. 154-155

Author(s):

E. G. Rightor

Keyword(s):

Excited State ◽

Polymer Blends ◽

Gas Phase ◽

Spatial Resolution ◽

High Spatial Resolution ◽

Electronic States ◽

Core Electron ◽

Bulk Solids ◽

Development Application

Core edge spectroscopy methods are versatile tools for investigating a wide variety of materials. They can be used to probe the electronic states of materials in bulk solids, on surfaces, or in the gas phase. This family of methods involves promoting an inner shell (core) electron to an excited state and recording either the primary excitation or secondary decay of the excited state. The techniques are complimentary and have different strengths and limitations for studying challenging aspects of materials. The need to identify components in polymers or polymer blends at high spatial resolution has driven development, application, and integration of results from several of these methods.

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