In situ Generation of Ruthenium Tetroxide and Osmium Tetroxide for the Physical Sciences and Their Reaction Indicators

Recently, there was a suggestion on the MSA listserver about the use of osmium tetroxide (OsO4 and how to handle it. One suggestion was that ampoules be scored, placed in a glass jar, and the ampoule smashed to release the contents. This seemed like a very unsafe way to use osmium tetroxide or ruthenium tetroxide. The purpose of this article is to suggest a way to generate smaller amounts of these compounds in a safer manner than smashing ampoules and wondering about what to do with the unused portion after staining or storing. Another purpose is to discuss a new reaction indicator for mainly osmium tetroxide. The use of a reaction specific indicator was mandatory for judging the level or degree to which staining had proceeded in thin sections for the transmission electron microscope (TEM).

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Development of a specimen holder for in situ generation of pure in-plane magnetic fields in a transmission electron microscope

Ultramicroscopy ◽

10.1016/s0304-3991(02)00264-4 ◽

2003 ◽

Vol 94 (3-4) ◽

pp. 193-196 ◽

Cited By ~ 18

Author(s):

T. Uhlig ◽

M. Heumann ◽

J. Zweck

Keyword(s):

Electron Microscope ◽

Magnetic Fields ◽

Transmission Electron Microscope ◽

Specimen Holder ◽

Transmission Electron ◽

In Situ Generation

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A TEM study of the microstructure of avian eggshells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100130146 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1102-1103

Author(s):

S. Q. Xiao ◽

S. Baden ◽

A. H. Heuer

Keyword(s):

Electron Microscope ◽

Calcium Carbonate ◽

Nucleation And Growth ◽

Growth Mechanisms ◽

Shell Surface ◽

Thin Sections ◽

Polycrystalline Metals ◽

Transmission Electron ◽

Nucleation And Growth Mechanisms

The avian eggshell is one of the most rapidly mineralizing biological systems known. In situ, 5g of calcium carbonate are crystallized in less than 20 hrs to fabricate the shell. Although there have been much work about the formation of eggshells, controversy about the nucleation and growth mechanisms of the calcite crystals, and their texture in the eggshell, still remain unclear. In this report the microstructure and microchemistry of avian eggshells have been analyzed using transmission electron microscope (TEM) and energy dispersive spectroscopy (EDS).Fresh white and dry brown eggshells were broken and fixed in Karnosky's fixative (kaltitanden) for 2 hrs, then rinsed in distilled H2O. Small speckles of the eggshells were embedded in Spurr medium and thin sections were made ultramicrotome.The crystalline part of eggshells are composed of many small plate-like calcite grains, whose plate normals are approximately parallel to the shell surface. The sizes of the grains are about 0.3×0.3×1 μm3 (Fig.l). These grains are not as closely packed as man-made polycrystalline metals and ceramics, and small gaps between adjacent grains are visible indicating the absence of conventional grain boundaries.

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Observations of thick and thin sections in a field-emission SEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100172826 ◽

1994 ◽

Vol 52 ◽

pp. 1018-1019

Author(s):

W. P. Wergin ◽

S. Roy ◽

E. F. Erbe ◽

C. A. Murphy ◽

C. D. Pooley

Keyword(s):

Electron Microscope ◽

Field Emission ◽

Room Temperature ◽

Osmium Tetroxide ◽

Uranyl Acetate ◽

Chemical Fixation ◽

Thin Sections ◽

Transmission Electron ◽

Conventional Transmission Electron Microscope ◽

Scanning Electron

Larvae of the nematode, Steinernema carpocapsae Weiser strain All, were cryofixed and freezesubstituted for 3 days in acetone containing 2% osmium tetroxide according to established procedures. Following chemical fixation, the nematodes were brought to room temperature, embedded in Spurr's medium and sectioned for observation with a Hitachi S-4100 field emission scanning electron microscope that was equipped with an Oxford CT 1500 Cryotrans System. Thin sections, about 80 nm thick, similar to those generally used in conventional transmission electron microscope (TEM) studies were mounted on copper grids and stained with uranyl acetate for 30 min and lead citrate for 5 min. Sections about 2 μm thick were also mounted and stained in a similar fashion. The grids were mounted on an Oxford grid holder, inserted into the microscope and onto a cryostage that was operated at ambient temperature. Thick and thin sections of the larvae were evaluated and photographed in the SEM at different accelerating voltages. Figs. 4 and 5 have undergone contrast conversion so that the images would resemble transmitted electron micrographs obtained with a TEM.

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Remote On-Line Control of a High-Voltage in situ Transmission Electron Microscope with A Rational User Interface

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100164386 ◽

1996 ◽

Vol 54 ◽

pp. 384-385

Author(s):

M.A. O’Keefe ◽

J. Taylor ◽

D. Owen ◽

B. Crowley ◽

K.H. Westmacott ◽

...

Keyword(s):

Electron Microscopy ◽

Electron Microscope ◽

User Interface ◽

Transmission Electron Microscope ◽

High Voltage ◽

Materials Science ◽

Transmission Electron ◽

On Line ◽

Electron Microscopes

Remote on-line electron microscopy is rapidly becoming more available as improvements continue to be developed in the software and hardware of interfaces and networks. Scanning electron microscopes have been driven remotely across both wide and local area networks. Initial implementations with transmission electron microscopes have targeted unique facilities like an advanced analytical electron microscope, a biological 3-D IVEM and a HVEM capable of in situ materials science applications. As implementations of on-line transmission electron microscopy become more widespread, it is essential that suitable standards be developed and followed. Two such standards have been proposed for a high-level protocol language for on-line access, and we have proposed a rational graphical user interface. The user interface we present here is based on experience gained with a full-function materials science application providing users of the National Center for Electron Microscopy with remote on-line access to a 1.5MeV Kratos EM-1500 in situ high-voltage transmission electron microscope via existing wide area networks. We have developed and implemented, and are continuing to refine, a set of tools, protocols, and interfaces to run the Kratos EM-1500 on-line for collaborative research. Computer tools for capturing and manipulating real-time video signals are integrated into a standardized user interface that may be used for remote access to any transmission electron microscope equipped with a suitable control computer.

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