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Abstract  

The daily variation of14C concentrations of liberated CO2 in the free fermentation process of Japanese SAKE brewing was studied. Each of the concentrations measured in the initial and final stages of the fermentation process correlated with levels of koji rice and steamed rice used for SAKE production, which had been obtained from different areas. This shows that analysis of fermenting CO2 of SAKE could be used to estimate the14C level in a local environment.

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Abstract  

Explosive depressurization offered an effective pre-treatment for isolating -cellulose from wood chips using the common chlorite method. This operation shortened the time required for isolation of -cellulose of relatively high purity by up to 6 h, and raised the relative crystallinity of the product to 65–72% from 50% or below for the unexploded samples. The steam-explosion was carried out by combining 2 min of pre-hydrolysis at a pressure of 3.55 MPa with a rapid decompression. This was found to be the best operating condition for pine wood chips of 1 mm thickness to analyze the tritium content in tree rings accurately.

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Abstract  

Technetium-99 was determined in nine human liver samples collected from autopsy of the subjects at the Niigata Prefecture Institute for Cancer Research Hospital. Even by using a very sensitive analytical procedure99Tc was detected in only one human liver sample. Though99Tc was detected in only one liver, nonetheless it is very important to study its distribution in the human body because of the contribution from fallout of nuclear weapons tests and prevalent use of99mTc in nuclear medicine.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
D. Assinder
,
M. Yamamoto
,
C. Kim
,
R. Seki
,
Y. Takaku
,
Y. Yamauchi
,
S. Igarashi
,
K. Komura
, and
K. Ueno

Abstract  

A survey has been carried out of40K,60Co,99Tc,106Ru,125Sb,129I,134Cs,137Cs,154Eu,226Ra,228Ra,237Np,238Pu,239,240Pu,241Pu,241Am,242Cm, and243,244Cm activities in sediments from the Irish Sea. Several of these radionuclides were measured independently at two separate laboratories to enable the intercomparison of the results produced. The comprehensive data set generated allows the present spatial distributions of these radionuclides in coastal sediments to be examined in relation to sediment textural characteristics and by comparison with earlier survey, enables the temporal trends in their activities to be determined. In general all artificial radionuclides showed lower activities in sediments in response to falling discharges from Sellafield and relationships with either grain size, distance from Sellafield or both. Isotope ratios were similar to cumulative weighted activity ratios rather than present day values due to sediment mixing. Pu levels supplied evidence for the lag in response of sediment deposits with increasing distance from Sellafield due to sediment transport.

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