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Title: FEASIBILITY OF A GRAPHITE-CARBON DIOXIDE IONIZATION CHAMBER TO MEASURE CARBON DOSE AT HIGH DOSE RATES. Period covered April 1957 to November 1957

Abstract

The feasibility of designing a graphite -carbon dioxide ionization chamber for the absolute measurement of the carbon dose rate from a pure gamma field up to 10/sup 10/ erg/g/hr is discussed. There are insufficient data on neutron response to judge the feasibility of using the ion chamber in mixed fields with large neutron components. (auth)

Authors:
Publication Date:
Research Org.:
Wright Air Development Center. Materials Lab., Wright-Patterson AFB, Ohio
OSTI Identifier:
4288335
Report Number(s):
WADC-TN-57-335; AD-142249; PB-
NSA Number:
NSA-13-003736
Resource Type:
Technical Report
Resource Relation:
Other Information: Project and Task title: NUCLEAR INSTRUMENTATION. Orig. Receipt Date: 31-DEC-59
Country of Publication:
Country unknown/Code not available
Language:
English
Subject:
INSTRUMENTS; CARBON; CARBON DIOXIDE; EFFICIENCY; GAMMA RADIATION; GRAPHITE; IONIZATION CHAMBERS; MEASURED VALUES; NEUTRONS; PLANNING; RADIATION DOSES; USES

Citation Formats

Hickmott, R.L. FEASIBILITY OF A GRAPHITE-CARBON DIOXIDE IONIZATION CHAMBER TO MEASURE CARBON DOSE AT HIGH DOSE RATES. Period covered April 1957 to November 1957. Country unknown/Code not available: N. p., 1957. Web.
Hickmott, R.L. FEASIBILITY OF A GRAPHITE-CARBON DIOXIDE IONIZATION CHAMBER TO MEASURE CARBON DOSE AT HIGH DOSE RATES. Period covered April 1957 to November 1957. Country unknown/Code not available.
Hickmott, R.L. Fri . "FEASIBILITY OF A GRAPHITE-CARBON DIOXIDE IONIZATION CHAMBER TO MEASURE CARBON DOSE AT HIGH DOSE RATES. Period covered April 1957 to November 1957". Country unknown/Code not available. doi:.
@article{osti_4288335,
title = {FEASIBILITY OF A GRAPHITE-CARBON DIOXIDE IONIZATION CHAMBER TO MEASURE CARBON DOSE AT HIGH DOSE RATES. Period covered April 1957 to November 1957},
author = {Hickmott, R.L.},
abstractNote = {The feasibility of designing a graphite -carbon dioxide ionization chamber for the absolute measurement of the carbon dose rate from a pure gamma field up to 10/sup 10/ erg/g/hr is discussed. There are insufficient data on neutron response to judge the feasibility of using the ion chamber in mixed fields with large neutron components. (auth)},
doi = {},
journal = {},
number = ,
volume = ,
place = {Country unknown/Code not available},
year = {Fri Nov 01 00:00:00 EST 1957},
month = {Fri Nov 01 00:00:00 EST 1957}
}

Technical Report:
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  • The two-fold purpose of this investigation has been to correlate the properties of smalls multicrystalline graphite specimens with the factors believed to influence them, and to assess the probability that graphite can conform to engineering specifications. The technique of differential thermal analysis was found applicable to investigating binder pyrolysis. Three promising binder materials were selected for future work: coal-tar pitchs furfuryl alcohol, and phenolberzaldebyde. The most illuminating properties cf experimental mixtures were found to bei apparent (water immersion) densitys dynamic (sonic) meduluss volume electrical resistance, and flexural strength. Measurements of medulus, strength, and thermal expansion have been carried out tomore » temperatures exceeding the creep threshold of graphites between 2l00 and 2250 C. Solvent mixing techniques for insuring homogeneous distribution of the binder were found to improve repreducibility, in all cases some change in the rheology of the system was observed with time. Maximum density and strength in pitch-bonded coke was achieved after agingss the mix at 125 C under partial vacuum. Maximum density consistent with good thermal shock resistance was obtained by adding Thermax to the coke flour. With 14 per cent by weight of Thermax specimens were made having dcnsities exeeeding 1.8 gm/cc with room-temperature strengths of about 2500 psi. Dynamic flexural moduli were measured for specimens heated and cooled between room tcmperature and 2650-C. Speeimens cut from a block of commercials impregnated, molded graphite increased 175 per cent in flexural strength when heated to 2000 C. Such heating caused a significant permanent change in dimensions modulus, and volume resistance. (auth)« less
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