scholarly journals Radioactivity of some natural and artificial radionuclides in coastal seawater at Ninh Thuan, Ba Ria - Vung Tau and Ca Mau provinces in 2018

2021 ◽  
Vol 10 (2) ◽  
pp. 44-51
Author(s):  
Tung Nguyen Dinh ◽  
Sieu Le Nhu ◽  
Phuc Nguyen Van ◽  
Phu Nguyen Van ◽  
Khoa Tran Dinh ◽  
...  

Radioactivities of some natural (Ra-226, Th-232, U-238, Po-210) and artificial (Cs-137, Sr-90 and Pu-239,240) radionuclides in coastal seawater at monitoring points of Ninh Thuan, Ba Ria - Vung Tau and Ca Mau provinces were analyzed quarterly in the year of 2018. Radioactivities of Ra-226, Th-232, U-238, and Cs-137 had been determined by simultaneous precipitation method and measured on low-level background gamma spectrometer; the radioactivities of Po-210 and Pu- 239,240 had been analyzed by radiochemical separation method and measured on alpha spectrometer; the radioactivity of Sr-90 had been analyzed by radiochemical separation method and measured on low-level background beta counting system. The ranges of radioactivities of Ra-226, Th-232, U-238, Po-210, Cs-137, Sr-90, and Pu-239,240 were 2.71 ÷ 15.91, 3.45 ÷ 35.93, 3.02 ÷ 21.47, 1.51÷ 6.74, 0.88 ÷ 1.68, 1.08 ÷ 1.86 and 0.0026 ÷ 0.0062 mBq/L, with the average values of 6.37, 12.67, 8.34, 3.29, 1.36, 1.46 and 0.0043 mBq/L, respectively. The results shown that the radioactivities of theabove-mentioned radionuclides varied between the seawaters at Ninh Thuan, Ba Ria - Vung Tau and Ca Mau seawater. Additionally, physicochemical parameters in seawater were also surveyed to assess their impact on the fluctuations of the above radionuclides.

1994 ◽  
Vol 45 (2) ◽  
pp. 251-256 ◽  
Author(s):  
Chu-Fang Wang ◽  
Jeng-Horng Lee ◽  
Horng-Jye Chiou

Radiocarbon ◽  
1989 ◽  
Vol 31 (03) ◽  
pp. 332-341 ◽  
Author(s):  
John E Noakes ◽  
Robert J Valenta

A Packard low-level liquid scintillation counting system is described which provides superior low-background beta-counting capability for3H and14C. The design is based on a novel pulse-discrimination circuit that separates background from valid scintillation pulses. Background discrimination is further enhanced by adding a plastic vial holder that acts as an anticoincidence guard. When excited by background radiation, the scintillation properties of the plastic provide an increased burst of photons to the detection electronics, which discriminate based on the number of component pulses in the burst. Experimental data demonstrate the low-level counting capabilities of this counter.


2019 ◽  
Vol 7 (2A) ◽  
Author(s):  
Roberto Pellacani Monteiro ◽  
Aluísio Souza Reis Junior ◽  
Geraldo Frederico Kastner ◽  
Eliane Silvia Codo Temba ◽  
Thiago César De Oliveira ◽  
...  

The aim of this work is to present radiochemical methodologies developed at CDTN/CNEN in order to answer a program for isotopic inventory of radioactive wastes from Brazilian Nuclear Power Plants.  In this program  some radionuclides, 3H, 14C, 55Fe, 59Ni, 63Ni, 90Sr, 93Zr, 94Nb, 99Tc, 129I, 235U, 238U, 238Pu, 239+240Pu, 241Pu, 242Pu, 241Am, 242Cm e 243+244Cm, were determined  in Low Level Wastes (LLW) and Intermediate Level Wastes (ILW) and a protocol of analytical methodologies based on radiochemical separation steps and spectrometric and nuclear techniques was stablished.


Radiocarbon ◽  
1995 ◽  
Vol 37 (2) ◽  
pp. 767-772 ◽  
Author(s):  
Kunio Omoto

The automatic β-counting system plays a significant role in obtaining high-level reproducibility and reliability in conventional radiocarbon dating. I review here the results achieved by using the “Fully Automatic Radiocarbon Dating System” developed by Omoto (1982). Since setting up the system in 1981, I was able not only to save operator time in β counting, but also to obtain accurate dates with only minimal uncertainties. Another positive result was the introduction of the automatic voltage correction program, which produced excellent results for counting sample materials over a long period.


1954 ◽  
Vol 25 (2) ◽  
pp. 153-157 ◽  
Author(s):  
G. L. Bate ◽  
H. L. Volchok ◽  
J. L. Kulp
Keyword(s):  

1972 ◽  
Vol 19 (1) ◽  
pp. 141-150 ◽  
Author(s):  
Norman Latner ◽  
Colin G. Sanderson
Keyword(s):  

2014 ◽  
Vol 37 (1) ◽  
pp. 38 ◽  
Author(s):  
A Baburajan ◽  
DD Rao ◽  
PM Ravi ◽  
V Sudheendran ◽  
RM Tripathi

Radiocarbon ◽  
1980 ◽  
Vol 22 (2) ◽  
pp. 461-469 ◽  
Author(s):  
H H Loosli ◽  
Martin Heimann ◽  
Hans Oeschger

Results of measurements in an underground laboratory, 70m of water equivalent below surface, are given. Background values of proportional gas counters with volumes between 16cc and 1.5L are lower by a factor of 2—4.5 compared to the values in the previously used laboratory (7m w.e.). High counting gas pressures, up to 5 at CH4 and up to 36 at P-10, enable the use of relatively small counters with correspondingly small background contributions from the walls. A separation of the residual background into different components is attempted, distinguishing a pressure dependent volume effect and surface correlated contributions. It can be shown that the selection of radioactively pure counter construction material is very important for a good low level counting system.


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