Improved sample cell design for optical studies of glass‐forming liquids in the 0–530 K range

Commissioning results of a liquid sample cell for X-ray reflectivity studies with anin situapplied electrical field are presented. The cell consists of a Plexiglas container with lateral Kapton windows for air–liquid and liquid–liquid interface studies, and was constructed with grooves to accept plate electrodes on the walls parallel to the direction of the beam. Both copper and ITO plate electrodes have been used, the latter being useful for simultaneous optical studies. Commissioning tests were made at the I07 beamline of the Diamond Light Source.

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Electron Microscopy of Silicon Nitride-Based Ceramics

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100088944 ◽

1991 ◽

Vol 49 ◽

pp. 926-927

Author(s):

Gareth Thomas

Keyword(s):

Electron Microscopy ◽

High Temperature ◽

Silicon Nitride ◽

World Wide ◽

Sintering Temperature ◽

Liquid Phase Sintering ◽

High Temperature Strength ◽

Sintering Additives ◽

Glass Forming ◽

Dense Product

Silicon nitride and silicon nitride based-ceramics are now well known for their potential as hightemperature structural materials, e.g. in engines. However, as is the case for many ceramics, in order to produce a dense product, sintering additives are utilized which allow liquid-phase sintering to occur; but upon cooling from the sintering temperature residual intergranular phases are formed which can be deleterious to high-temperature strength and oxidation resistance, especially if these phases are nonviscous glasses. Many oxide sintering additives have been utilized in processing attempts world-wide to produce dense creep resistant components using Si3N4 but the problem of controlling intergranular phases requires an understanding of the glass forming and subsequent glass-crystalline transformations that can occur at the grain boundaries.

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Contrast and Resolution in Alfresco Microscopy and Thick Specimens

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100096102 ◽

1972 ◽

Vol 30 ◽

pp. 570-571

Author(s):

J. R. Sellar ◽

J. M. Cowley

Keyword(s):

Solid Material ◽

Cell Design ◽

Current Interest ◽

High Voltage Electron Microscopy ◽

Voltage Electron ◽

Transmission Electron ◽

Environmental Cell ◽

Scanning Transmission ◽

Conventional Transmission Electron Microscope ◽

Transmission Microscope

Current interest in high voltage electron microscopy, especially in the scanning mode, has prompted the development of a method for determining the contrast and resolution of images of specimens in controlled-atmosphere stages or open to the air, hydrated biological specimens being a good example. Such a method would be of use in the prediction of microscope performance and in the subsequent optimization of environmental cell design for given circumstances of accelerating voltage, cell gas pressure and constitution, and desired resolution.Fig. 1 depicts the alfresco cell of a focussed scanning transmission microscope with a layer of gas L (and possibly a thin window W) between the objective O and specimen T. Using the principle of reciprocity, it may be considered optically equivalent to a conventional transmission electron microscope, if the beams were reversed. The layer of gas or solid material after the specimen in the STEM or before the specimen in TEM has no great effect on resolution or contrast and so is ignored here.

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The effect of an aluminum heat-sink layer on the laser-induced amorphization of SiOx/TeGeSn/SiOx phase-change recording films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100154846 ◽

1989 ◽

Vol 47 ◽

pp. 574-575

Author(s):

Matthew R. Libera ◽

Martin Chen

Keyword(s):

Thin Film ◽

Phase Change ◽

Heat Sink ◽

Multilayer Film ◽

Glassy Phase ◽

Film Structure ◽

Glass Forming ◽

Active Storage ◽

Dielectric Layers ◽

Amorphous States

Phase-change erasable optical storage is based on the ability to switch a micron-sized region of a thin film between the crystalline and amorphous states using a diffraction-limited laser as a heat source. A bit of information can be represented as an amorphous spot on a crystalline background, and the two states can be optically identified by their different reflectivities. In a typical multilayer thin-film structure the active (storage) layer is sandwiched between one or more dielectric layers. The dielectric layers provide physical containment and act as a heat sink. A viable phase-change medium must be able to quench to the glassy phase after melting, and this requires proper tailoring of the thermal properties of the multilayer film. The present research studies one particular multilayer structure and shows the effect of an additional aluminum layer on the glass-forming ability.

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