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Volume 16 (1981)
- Issue 4 Pages 277-
- Issue 3 Pages 201-
- Issue 2 Pages 83-
- Issue 1 Pages 1-
Volume 16, Issue 1
Displaying 1-10 of 10 articles from this issue
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Toshi NAGAOKA, Ryuichi SAKAMOTO, Kimiaki SAITO, Shigeru MORIUCHI1981 Volume 16 Issue 1 Pages 1-10
Published: 1981
Released on J-STAGE: February 25, 2010
JOURNAL FREE ACCESSAngular distributions of exposure rate in natural radiation environment were measured using a 1″φ×1″ NaI (Tl) scintillation detector which was placed on the axis of a set of concentric circular lead shieldings. Incident polar angle of γ ray was determined by changing the relative position between the detector and the shieldings. Incident γ rays were integrated over the whole azimuthal angle (0-2π) in each polar angle. And then, the angular distribution was obtained by subtracting the responses between each polar angle.
As the incident solid angle of γ ray could be set large enough, it was possible not only to set the measuring time short but also to measure with high accuracy.
Measurements were made under various environmental conditions; two on open field and one in a pine grove at a height of 1m, and one at a height of 10m on a tower. And also, one measurement was made in a one-storied wooden house. Experimental results supported the angular distributions expected from calculations, previously reported by other authors, and it was shown that this method can be applied well even where a calculational evaluation is difficult due to the complexity of its topography.View full abstractDownload PDF (2370K) -
Masami FUKUI, Shigeo UCHIDA, Kousuke KATSURAYAMA1981 Volume 16 Issue 1 Pages 11-21
Published: 1981
Released on J-STAGE: February 25, 2010
JOURNAL FREE ACCESSStudies were conducted to estimate the contamination spread resulting from the radioactive waste disposal into a subsurface aquifer. A general equation, expressing the contaminated zone as a function of radioactive decay, the physical and chemical parameters of soil is presented. A distribution coefficient was also formulated which can be used to judge the suitability of a site for waste disposal. Moreover, a method for predicting contaminant concentration in groundwater at a site boundary is suggested for a heterogeneous media where the subsurface aquifer has different values of porosity, density, flow velocity, distribution coefficient and so on.
A general equation was also developed to predict the distribution of radionuclides resulting from the disposal of a solid waste material. The distributions of contamination was evaluated for 90Sr and 239Pu which obey a linear adsorption model and a first order kinetics respectively. These equations appear to have practical utility for easily estimating groundwater contamination.View full abstractDownload PDF (1370K) -
Michikuni SHIMO, Jun-ichi UEDA, Yukimasa IKEBE1981 Volume 16 Issue 1 Pages 23-32
Published: 1981
Released on J-STAGE: February 25, 2010
JOURNAL FREE ACCESSMeasurements of the size distribution of naturally occuring radioactive aerosols (short-lived radon daughters) have been carried out by a diffusion battery method in a tunnel. Three kinds of analytical methods —log-normal method, response matrix method, and graphical stripping method— were applied to the estimation of a size distribubution from observed relationships between radioactivity and flow rate. The activity distributions obtained were almost equal in form and also equal to those which were estimated from non-radioactive particle size distributions measured simultaneously.View full abstractDownload PDF (1174K) -
Hideharu ISHIGURO1981 Volume 16 Issue 1 Pages 33-38
Published: 1981
Released on J-STAGE: February 25, 2010
JOURNAL FREE ACCESSData processing system of personnel exposure was developed at PNC Tokai Works. This system consists of host and terminal computer system with four character displays. Data multi-check system and ease of operation were considered in the design of this system.
This system has two main functions: the first is the storage of all personnel exposure data in PNC and the second is the semi-automatic processing of thermoluminescence values measured by manual TLD readers.
All TL elements in the TLD badges for whole body exposure and the finger rings for extremity exposure are measured by three manual TLD readers and simultaneously the results are sent to computer system by means of three character displays.
This system is availabe to the applications for the national registration center.View full abstractDownload PDF (746K) -
Hideharu MATSUDA, Shigeko FURUKAWA, Tokishi KAMINISHI1981 Volume 16 Issue 1 Pages 39-42
Published: 1981
Released on J-STAGE: February 25, 2010
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Noboru YAMAGATA, Koichi NISHIMURA, Takeo HASHIMOTO1981 Volume 16 Issue 1 Pages 43-50
Published: 1981
Released on J-STAGE: February 25, 2010
JOURNAL FREE ACCESSIn connection with the operation of the first spent fuel reprocessing plant in Japan, the monitoring of marine sediment off the coast of Tokai-mura is needed to detect the influence of radioactive effluent from the plant. However, some projects of point-sampling of marine sediment in this area have revealed a wide range of variation from place to place in the concentrations of fallout radionuclides distributed by nuclear weapons tests. Accordingly, a sampling design to detect any significant change by year of environmental levels of radionuclides in sediment should involve the sampling of sediment from a number of point in order to satisfy a given confidence level. A new method of line-sampling has been developed as a substitute for point-sampling at many points. The principle of this method comprised of resuspension of sediment by dragging a muddler on the bottom and collection of suspended sediment by a net type collector set up on a sledge. Operation of line-sampling by use of this apparatus and point-sampling by use of Smith-McIntyre grab sampler were made at two locations of different type and comparison of the analytical data for collected sediment was made. The sampling off Tokaimura (open sea, sandy sediment), where 137Cs was analyzed, showed a good coincidence between the two method, while the sampling in Urazoko-bay (silty sediment), where both 137Cs and 60Co were analyzed, showed a discrepancy suggesting a loss of fine silty sediment in the line-sampling method.View full abstractDownload PDF (2272K) -
Katsuzo KOIZUMI, Hideharu ISHIGURO, Seiji FUKUDA1981 Volume 16 Issue 1 Pages 51-59
Published: 1981
Released on J-STAGE: February 25, 2010
JOURNAL FREE ACCESSCommitted dose equivalent for inhaled 239Pu was calculated on the basis of the method given by ICRP publication 30. The procedures were presented for the calculation of the total quantity of activity in each compartment of respiratory system and several organs at time t and for the calculation of the integrated dose equivalent in several organs by single intake due to 239Pu inhalation.
In order to apply to the monitorng of internal exposure, dependence of the committed dose equivalent on particle size (AMAD) and of activity in excreted feces on particle size (AMAD) was examined for inhaled 239Pu class Y and class W, respectively. By using the results obtained, the inhaled 239Pu is determined by the measurement of the activity in excreted feces.View full abstractDownload PDF (860K) -
[in Japanese]1981 Volume 16 Issue 1 Pages 61-63
Published: 1981
Released on J-STAGE: February 25, 2010
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1981 Volume 16 Issue 1 Pages 81a-82
Published: 1981
Released on J-STAGE: February 25, 2010
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1981 Volume 16 Issue 1 Pages 81b-82
Published: 1981
Released on J-STAGE: February 25, 2010
JOURNAL FREE ACCESSDownload PDF (147K)
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