New Static Apparatus and Vapor Pressure of Reference Materials:  Naphthalene, Benzoic Acid, Benzophenone, and Ferrocene

Benzylamine tartrate (m.p. 63°C) seems to be a better and more convenient substrate for making carbon films than any of those previously proposed. Using it in the manner described, it is easy consistently to make batches of specimen grids as open as 200 mesh with no broken squares, and without individual handling of the grids. Benzylamine tartrate (hereafter called B.T.) is a viscous liquid when molten, which sets to a glass. Unlike polymeric substrates it does not swell before dissolving; such swelling of the substrate seems to be a principal cause of breakage of carbon film. Mass spectroscopic examination indicates a vapor pressure less than 10−9 Torr at room temperature.

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Hydration Chamber for Jeolco 200 Kv Microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100069703 ◽

1970 ◽

Vol 28 ◽

pp. 542-543

Author(s):

V. R. Matricardi ◽

G. G. Hausner ◽

D. F. Parsons

Keyword(s):

Electron Microscope ◽

Water Vapor ◽

Vapor Pressure ◽

Pressure Gradient ◽

Room Temperature ◽

List Type ◽

Type Number ◽

Equilibrium Vapor Pressure

In order to observe room temperature hydrated specimens in an electron microscope, the following conditions should be satisfied: The specimen should be surrounded by water vapor as close as possible to the equilibrium vapor pressure corresponding to the temperature of the specimen.The specimen grid should be inserted, focused and photo graphed in the shortest possible time in order to minimize dehydration.The full area of the specimen grid should be visible in order to minimize the number of changes of specimen required.There should be no pressure gradient across the grid so that specimens can be straddled across holes.Leakage of water vapor to the column should be minimized.

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Layered and ion implantation specimens as possible reference materials for the electron-probe microanalysis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100132893 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1652-1653

Author(s):

G. Remond ◽

R.H. Packwood ◽

C. Gilles ◽

S. Chryssoulis

Keyword(s):

Ion Implantation ◽

Reference Materials ◽

Analytical Techniques ◽

Thin Film Deposition ◽

Film Deposition ◽

X Ray ◽

Spatially Resolved ◽

Analytical Expressions ◽

Original Approach ◽

Depth Concentration

Merits and limitations of layered and ion implanted specimens as possible reference materials to calibrate spatially resolved analytical techniques are discussed and illustrated for the case of gold analysis in minerals by means of x-ray spectrometry with the EPMA. To overcome the random heterogeneities of minerals, thin film deposition and ion implantation may offer an original approach to the manufacture of controlled concentration/ distribution reference materials for quantification of trace elements with the same matrix as the unknown.In order to evaluate the accuracy of data obtained by EPMA we have compared measured and calculated x-ray intensities for homogeneous and heterogeneous specimens. Au Lα and Au Mα x-ray intensities were recorded at various electron beam energies, and hence at various sampling depths, for gold coated and gold implanted specimens. X-ray intensity calculations are based on the use of analytical expressions for both the depth ionization Φ (ρz) and the depth concentration C (ρz) distributions respectively.

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TEM characterization of proton-exchanged LiNbO3 optical waveguides

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010014395x ◽

1986 ◽

Vol 44 ◽

pp. 480-481

Author(s):

W. E. Lee

Keyword(s):

Refractive Index ◽

Benzoic Acid ◽

Optical Waveguides ◽

Total Internal Reflection ◽

Index Of Refraction ◽

Optical Measurements ◽

Lithium Ions ◽

Wide Channel ◽

Tem Characterization

An optical waveguide consists of a several-micron wide channel with a slightly different index of refraction than the host substrate; light can be trapped in the channel by total internal reflection.Optical waveguides can be formed from single-crystal LiNbO3 using the proton exhange technique. In this technique, polished specimens are masked with polycrystal1ine chromium in such a way as to leave 3-13 μm wide channels. These are held in benzoic acid at 249°C for 5 minutes allowing protons to exchange for lithium ions within the channels causing an increase in the refractive index of the channel and creating the waveguide. Unfortunately, optical measurements often reveal a loss in waveguiding ability up to several weeks after exchange.

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