A Novel Peninsula-island Structure for Sensing Ultra-low Pressure Based on Dry-wet Combination Etching Process

The attack, on the surface of a polymer, by the atomic, molecular and ionic species that are created in a low pressure electrical discharge in a gas is interesting because: 1) significant interior morphological features may be revealed, 2) dielectric breakdown of polymeric insulation on high voltage power distribution lines involves the attack on the polymer of such species created in a corona discharge, 3) adhesive bonds formed between polymer surfaces subjected to such SDecies are much stronger than bonds between untreated surfaces, 4) the chemical modification of the surface creates a reactive surface to which a thin layer of another polymer may be bonded by glow discharge polymerization.

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Field ion microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100104236 ◽

1988 ◽

Vol 46 ◽

pp. 434-435

Author(s):

Gert Ehrlich

Keyword(s):

Low Temperature ◽

Sample Surface ◽

Low Pressure ◽

Radius Of Curvature ◽

Field Ion Microscopy ◽

Phosphor Screen ◽

Ion Microscopy ◽

Field Ion Microscope

The field ion microscope, devised by Erwin Muller in the 1950's, was the first instrument to depict the structure of surfaces in atomic detail. An FIM image of a (111) plane of tungsten (Fig.l) is typical of what can be done by this microscope: for this small plane, every atom, at a separation of 4.48Å from its neighbors in the plane, is revealed. The image of the plane is highly enlarged, as it is projected on a phosphor screen with a radius of curvature more than a million times that of the sample. Müller achieved the resolution necessary to reveal individual atoms by imaging with ions, accommodated to the object at a low temperature. The ions are created at the sample surface by ionization of an inert image gas (usually helium), present at a low pressure (< 1 mTorr). at fields on the order of 4V/Å.

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Sem Observations in Gastric Mucosa Exposed to Progressive Enzymatic Etching

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s1431927600002531 ◽

1980 ◽

Vol 38 ◽

pp. 570-571

Author(s):

C.A.E. Lemmi ◽

D. Booth ◽

G.E. Adomian

Keyword(s):

Gastric Mucosa ◽

Critical Point ◽

Proteolytic Activity ◽

Etching Process ◽

Cellular Types

In order to enrich populations of homogeneous cellular types we dissociated gastric mucosa by enzymatic techniques. In addition, we used SEM to monitor the progressive etching of the mucosa. Two enzymes were tested: collagenase III with minimum proteolytic activity and Pronase with broader proteolytic effects. The gastric mucosa was exposed to the effect of the enzymes using everted stomach preparations. In this way the digestive action occured progressively from the lumen of the stomach toward the base of the glands. This “etching” process could be monitored conveniently by SEM. After incubation for periods varying from 30 to 210 minutes the tissues were stretched on dental wax, fixed in 2 % glutaralheyde, post-fixed in osmium, dehydrated, critical point dryed and coated with gold. A model MSM-5 “Mini-SEM” was used for observation. Gentle uncurling of the preparation before coating with gold produced fractures which revealed the structure of the gastric glandsin more detail.

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