Optical Microscopy Shared Resource

Dislocations, Ordering and Antiferromagnetic Domains in MnO

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100069600 ◽

1970 ◽

Vol 28 ◽

pp. 522-523

Author(s):

D. J. Barber ◽

R. G. Evans

Keyword(s):

Electron Diffraction ◽

Single Crystal ◽

Optical Microscopy ◽

Defect Chemistry ◽

Magnetic Structures ◽

Optically Transparent ◽

Magnetic Features ◽

Antiferromagnetic Domains

Manganese (II) oxide, MnO, in common with CoO, NiO and FeO, possesses the NaCl structure and shows antiferromagnetism below its Neel point, Tn∼ 122 K. However, the defect chemistry of the four oxides is different and the magnetic structures are not identical. The non-stoichiometry in MnO2 small (∼2%) and below the Tn the spins lie in (111) planes. Previous work reported observations of magnetic features in CoO and NiO. The aim of our work was to find explanations for certain resonance results on antiferromagnetic MnO.Foils of single crystal MnO were prepared from shaped discs by dissolution in a mixture of HCl and HNO3. Optical microscopy revealed that the etch-pitted foils contained cruciform-shaped precipitates, often thick and proud of the surface but red-colored when optically transparent (MnO is green). Electron diffraction and probe microanalysis indicated that the precipitates were Mn2O3, in contrast with recent findings of Co3O4 in CoO.

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A method to measure pores and fissures in geologic materials under S.E.M. by digital image processing

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100108209 ◽

1978 ◽

Vol 36 (1) ◽

pp. 212-213

Author(s):

L. Montoto ◽

M. Montoto ◽

A. Bel-Lan

Keyword(s):

Image Processing ◽

Optical Microscopy ◽

Digital Image Processing ◽

Digital Image ◽

Digital Processing ◽

Free Surfaces ◽

Geologic Materials ◽

Automatic Information ◽

Detector Output ◽

Rock Specimens

INTRODUCTION.- The physical properties of rock masses are greatly influenced by their internal discontinuities, like pores and fissures. So, these need to be measured as a basis for interpretation. To avoid the basic difficulties of measurement under optical microscopy and analogic image systems, the authors use S.E.M. and multiband digital image processing. In S.E.M., analog signal processing has been used to further image enhancement (1), but automatic information extraction can be achieved by simple digital processing of S.E.M. images (2). The use of multiband image would overcome difficulties such as artifacts introduced by the relative positions of sample and detector or the typicals encountered in optical microscopy.DIGITAL IMAGE PROCESSING.- The studied rock specimens were in the form of flat deformation-free surfaces observed under a Phillips SEM model 500. The SEM detector output signal was recorded in picture form in b&w negatives and digitized using a Perkin Elmer 1010 MP flat microdensitometer.

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Digital imaging: When should one take the plunge?

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100165471 ◽

1996 ◽

Vol 54 ◽

pp. 602-603

Author(s):

John F. Mansfield

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Transmission Electron Microscopy ◽

Optical Microscopy ◽

Digital Imaging ◽

Storage Devices ◽

Major Benefit ◽

Transmission Electron ◽

New Instrument ◽

Scanning Electron

The current imaging trend in optical microscopy, scanning electron microscopy (SEM) or transmission electron microscopy (TEM) is to record all data digitally. Most manufacturers currently market digital acquisition systems with their microscope packages. The advantages of digital acquisition include: almost instant viewing of the data as a high-quaity positive image (a major benefit when compared to TEM images recorded onto film, where one must wait until after the microscope session to develop the images); the ability to readily quantify features in the images and measure intensities; and extremely compact storage (removable 5.25” storage devices which now can hold up to several gigabytes of data).The problem for many researchers, however, is that they have perfectly serviceable microscopes that they routinely use that have no digital imaging capabilities with little hope of purchasing a new instrument.

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X-ray Crystallography Shared Resource

10.32388/7yipw5 ◽

2020 ◽

Author(s):

Keyword(s):

Shared Resource ◽

X Ray ◽

X Ray Crystallography

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Improved Autoadhesion Measurement Method for Micromachined Polysilicon Beams

MRS Proceedings ◽

10.1557/proc-444-87 ◽

1996 ◽

Vol 444 ◽

Cited By ~ 5

Author(s):

Maarten P. de Boer ◽

Terry A. Michalske

Keyword(s):

Surface Chemistry ◽

Optical Microscopy ◽

Measurement Method ◽

Current Practice ◽

Cantilever Beams ◽

Beam Length ◽

Substrate Adhesion

AbstractWe have measured autoadhesion (e.g. stiction) of individual polysilicon beams by interferometric optical microscopy. Untreated cantilever beams were dried from water in air, while treated beams were coated with a hydrophobic molecular coating of octadecyltrichlorosilane (ODTS). Adhesion values obtained for beams adhered to the substrate over a long length (large d) are independent of beam length with values of 16.7 and 4.4 mJ/m2 for untreated and treated samples respectively. These values can be understood in terms of differences in surface chemistry and polysilicon roughness. Using the shortest length beam which remains attached to the substrate, adhesion values were 280 and 16 mJ/m2 respectively. These higher values may be a result of capillarity effects. We recommend that measurements be made on beams in which d is large, in contrast to the current practice of noting the shortest beam adhered.

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Rapidly Solidified Melt-spun Bi-Sn Ribbons: Surface Composition Issues

JOURNAL OF ADVANCES IN PHYSICS ◽

10.24297/jap.v11i5.369 ◽

2016 ◽

pp. 3287-3297

Author(s):

Tarek El Ashram ◽

Ana P. Carapeto ◽

Ana M. Botelho do Rego

Keyword(s):

Chemical Composition ◽

Optical Microscopy ◽

Melt Spinning ◽

Surface Composition ◽

Electrochemical Process ◽

Melt Spun ◽

Bismuth Alloy ◽

The One ◽

Rapidly Solidified ◽

Melt Spinning Technique

Tin-bismuth alloy ribbons were produced using melt-spinning technique. The two main surfaces (in contact with the rotating wheel and exposed to the air) were characterized with Optical Microscopy and AFM, revealing that the surface exposed to the air is duller (due to a long-range heterogeneity) than the opposite surface. Also the XPS chemical composition revealed many differences between them both on the corrosion extension and on the total relative amounts of tin and bismuth. For instance, for the specific case of an alloy with a composition Bi-4 wt % Sn, the XPS atomic ratios Sn/Bi are 1.1 and 3.7 for the surface in contact with the rotating wheel and for the one exposed to air, respectively, showing, additionally, that a large segregation of tin at the surface exists (nominal ratio should be 0.073). This segregation was interpreted as the result of the electrochemical process yielding the corrosion products.

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