High Frequency Electrodeless Discharge System for Ashing Organic Matter.

Gleit, Chester E.

doi:10.1021/ac60221a050

Cited by 28 publications

(6 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This type of plasma has long been known to have a catalytic effect in oxidizing virtually all types of carbonaceous materials (Gleit & Holland 1962;Gleit 1965;Hollahan 1966). The atomic oxygen and excited molecular species produced in the discharge readily react with organic matter in the paint, forming CO2 and H2O.…”

Section: Methods I -Sample Datingmentioning

confidence: 99%

“…We use a radiofrequency (RF) generated low-temperature (-175°C), low-pressure (-.1 torr) oxygen plasma to separate the organic matter from the carbonate substrate by oxidizing the organic material to carbon dioxide (C02). This type of plasma has long been known to have a catalytic effect in oxidizing virtually all types of carbonaceous materials (Gleit & Holland 1962;Gleit 1965;Hollahan 1966). The atomic oxygen and excited molecular species produced in the discharge readily react with organic matter in the paint, forming CO2 and H2O.…”

Section: Methods I -Sample Datingmentioning

confidence: 99%

See 1 more Smart Citation

Direct Radiocarbon Dating of Rock Art

1992

View full text Add to dashboard Cite

ABSTRACT. In 14C dating of pictographs, we use a low-temperature oxygen plasma coupled with high-vacuum techniques to selectively remove carbon-containing material in the paint without contamination from the rock substrate, even if limestone (CaCO3). In addition to one previously published measurement, we analyzed two more pictograph samples, which are in accord with archaeological inference. A sample of known age charcoal, also processed by our method, matched the control. This technique produces little mass fractionation, the maximum 813C being 0.16%o from the untreated sample. Limestone decomposition does not occur during our procedure. Although the technique development is in its infancy, these new results demonstrate that our non-destructive technique has great potential for producing accurate 14C ages.

show abstract

Section: Methods I -Sample Datingmentioning

confidence: 99%

Section: Methods I -Sample Datingmentioning

confidence: 99%

Direct Radiocarbon Dating of Rock Art

1992

View full text Add to dashboard Cite

show abstract

“…Experimental details are described elsewhere (Chaffee et al l993c) and are presented here only in general terms. Oxygen plasmas have been used since the 1960s to react away the organic component of coal and other organic matter while leaving the mineral portions (including carbonates) unreacted (Gleit and Holland 1962;Gleit 1965;Hollahan 1966). The restrictions for radiocarbon dating on nonreactivity of carbonates in an oxygen plasma were, however, much more stringent than those for the coal studies.…”

Section: Experimental Techniquementioning

confidence: 99%

New Light on Old Art: Recent Advances in Hunter-Gatherer Rock Art Research

Ouzman¹,

Whitley²,

Loendorf³

1995

The South African Archaeological Bulletin

View full text Add to dashboard Cite

, of the Publications staff of The UCLA Institute of Archaeology for their help in the preparation of this book. A special thanks goes to Janet Lever, whose tracing provided the cover art. DAVID s. WHITLEY LAWRENCE L. LOENDORF In the far west, Cressman (1937) for Oregon, and Heizer and Baumhoff (1962) for Nevada and eastern California, provided the most significant major studies. Heizer and Baumhoff's (1962) research has probably been the most influential in North Americ~ since Steward's. Their research was heavily influenced by Steward, as well as by the evolutionist writings of French 'primitive mentality' rather than reliable ethnography" (Lewis-Williams 1982:430) and, by about mid-century, it had been dis

show abstract

“…The low temperature asher (Tracerlab Div ., Richmond, Calif ., LTA-600) converts relatively unreactive molecular oxygen to an excited plasma which removes organic substances and leaves mineral deposits (see Gleit and Holland, 1962 ;Gleit, 1963Gleit, , 1965Gleit, , 1966Hollahan, 1966) . The excited plasma is formed as molecular oxygen passes through an electromagnetic field .…”

Section: The Low Temperature Ashermentioning

confidence: 99%

Low Temperature Ultramicroincineration of Thin-Sectioned Tissue

Hohman

Schraer

1972

The Journal of Cell Biology

View full text Add to dashboard Cite

Low temperature ultramicroincineration was employed to determine the morphological localization of "structure-bound" mineral and/or metallic elements within biological cells at the electron microscope level . This technique chemically removes organic material from thin sections of tissues with reactive, excited oxygen instead of heat as used in a furnace . The remaining ash representing the mineral/metallic ultrastructure of cells is advantageous for ultrastructural studies because incineration without applying heat is less destructive than the burning associated with high temperatures . This low temperature incineration method was applied to thin-sectioned avian shell gland mucosa, a calcium transporting system, as a sample tissue . The results include : recognition of many subcellular organelles in the ash patterns, identification of dense, ash-containing granules (possibly organic-metallic complexes) in epithelial cells which may be involved in calcium transport, description of ashed erythrocytes and collagen, comparison of ashed glutaraldehyde fixed tissue with and without osmium postfixation, description of lead-stained cells after ashing, demonstration that ash preservation is dependent upon section thickness, illustration of the fine resolution obtainable because the ash residues remain relatively near their in situ origins, discussion of technical problems in this relatively new field, and demonstration of the presence of Ca and P in the ash with electron microprobe X-ray analysis .

show abstract

High Frequency Electrodeless Discharge System for Ashing Organic Matter.

Cited by 28 publications

References 5 publications

Direct Radiocarbon Dating of Rock Art

Direct Radiocarbon Dating of Rock Art

New Light on Old Art: Recent Advances in Hunter-Gatherer Rock Art Research

Low Temperature Ultramicroincineration of Thin-Sectioned Tissue

Contact Info

Product

Resources

About