Convergent Richtmyer–Meshkov instability of light gas layer with perturbed outer surface

The authors have investigated the dissolution process of human cholesterol gallstones using a scanning electron microscope(SEM). This study was carried out by comparing control gallstones incubated in beagle bile with gallstones obtained from patients who were treated with chenodeoxycholic acid(CDCA).The cholesterol gallstones for this study were obtained from 14 patients. Three control patients were treated without CDCA and eleven patients were treated with CDCA 300-600 mg/day for periods ranging from four to twenty five months. It was confirmed through chemical analysis that these gallstones contained more than 80% cholesterol in both the outer surface and the core.The specimen were obtained from the outer surface and the core of the gallstones. Each specimen was attached to alminum sheet and coated with carbon to 100Å thickness. The SEM observation was made by Hitachi S-550 with 20 kV acceleration voltage and with 60-20, 000X magnification.

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Simple Identification of Electron Diffraction Ring Patterns

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100062713 ◽

1969 ◽

Vol 27 ◽

pp. 160-161

Author(s):

Carolyn Nohr ◽

Ann Ayres

Keyword(s):

Electron Microscope ◽

Electron Diffraction ◽

Diffraction Ring ◽

Image Position

Texts on electron diffraction recommend that the camera constant of the electron microscope be determine d by calibration with a standard crystalline specimen, using the equation

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Atomic orientation effects in proton stopping at low velocity

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100077116 ◽

1983 ◽

Vol 41 ◽

pp. 708-709

Author(s):

Kin Lam

Keyword(s):

Polycrystalline Material ◽

Charged Particles ◽

Target Material ◽

Stopping Power ◽

Low Velocity ◽

Electronic Density ◽

Interatomic Distances ◽

Frame Work ◽

Image Position ◽

Atomic Orientation

The energy of moving ions in solid is dependent on the electronic density as well as the atomic structural properties of the target material. These factors contribute to the observable effects in polycrystalline material using the scanning ion microscope. Here we outline a method to investigate the dependence of low velocity proton stopping on interatomic distances and orientations.The interaction of charged particles with atoms in the frame work of the Fermi gas model was proposed by Lindhard. For a system of atoms, the electronic Lindhard stopping power can be generalized to the formwhere the stopping power function is defined as

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A SEM and Light Microscope Study of the Epidermal Leaf Structures of the Carnivorous Plant, Sarracenia purpurea, L.

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100065833 ◽

1971 ◽

Vol 29 ◽

pp. 358-359

Author(s):

B. J. Panessa ◽

J. F. Gennaro

Keyword(s):

Methylene Blue ◽

Toluidine Blue ◽

Outer Surface ◽

Microscope Study ◽

Light Microscope ◽

Carnivorous Plant ◽

Sarracenia Purpurea ◽

Inner Surface

Tissue from the hood and sarcophagus regions were fixed in 6% glutaraldehyde in 1 M.cacodylate buffer and washed in buffer. Tissue for SEM was partially dried, attached to aluminium targets with silver conducting paint, carbon-gold coated(100-500Å), and examined in a Kent Cambridge Stereoscan S4. Tissue for the light microscope was post fixed in 1% aqueous OsO4, dehydrated in acetone (4°C), embedded in Epon 812 and sectioned at ½u on a Sorvall MT 2 ultramicrotome. Cross and longitudinal sections were cut and stained with PAS, 0.5% toluidine blue and 1% azure II-methylene blue. Measurements were made from both SEM and Light micrographs.The tissue had two structurally distinct surfaces, an outer surface with small (225-500 µ) pubescent hairs (12/mm2), numerous stoma (77/mm2), and nectar glands(8/mm2); and an inner surface with large (784-1000 µ)stiff hairs(4/mm2), fewer stoma (46/mm2) and larger, more complex glands(16/mm2), presumably of a digestive nature.

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A Magnetic Spectrometer for a Scanning Transmission Electron Microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100052195 ◽

1974 ◽

Vol 32 ◽

pp. 436-437

Author(s):

A. Kosiara ◽

J. W. Wiggins ◽

M. Beer

Keyword(s):

Scanning Transmission Electron Microscope ◽

Magnetic Spectrometer ◽

Fringe Field ◽

Curvature Radius ◽

Magnetic Pole ◽

Quadrupole Field ◽

Transmission Electron ◽

Scanning Transmission ◽

Under Construction ◽

Image Position

A magnetic spectrometer to be attached to the Johns Hopkins S. T. E. M. is under construction. Its main purpose will be to investigate electron interactions with biological molecules in the energy range of 40 KeV to 100 KeV. The spectrometer is of the type described by Kerwin and by Crewe Its magnetic pole boundary is given by the equationwhere R is the electron curvature radius. In our case, R = 15 cm. The electron beam will be deflected by an angle of 90°. The distance between the electron source and the pole boundary will be 30 cm. A linear fringe field will be generated by a quadrupole field arrangement. This is accomplished by a grounded mirror plate and a 45° taper of the magnetic pole.

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Optimizing conditions for x-ray microchemical analysis in analytical electron microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100109884 ◽

1978 ◽

Vol 36 (1) ◽

pp. 548-549 ◽

Cited By ~ 2

Author(s):

N. J. Zaluzec

Keyword(s):

Solid Angle ◽

Analytical Electron Microscopy ◽

Incident Beam ◽

Thin Foil ◽

Experimental Conditions ◽

X Ray ◽

Microchemical Analysis ◽

Analytical Electron ◽

Image Position ◽

Incident Beam Energy

The ultimate sensitivity of microchemical analysis using x-ray emission rests in selecting those experimental conditions which will maximize the measured peak-to-background (P/B) ratio. This paper presents the results of calculations aimed at determining the influence of incident beam energy, detector/specimen geometry and specimen composition on the P/B ratio for ideally thin samples (i.e., the effects of scattering and absorption are considered negligible). As such it is assumed that the complications resulting from system peaks, bremsstrahlung fluorescence, electron tails and specimen contamination have been eliminated and that one needs only to consider the physics of the generation/emission process.The number of characteristic x-ray photons (Ip) emitted from a thin foil of thickness dt into the solid angle dΩ is given by the well-known equation

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