Authors:M. Moldovan, C. Cosma, I. Encian, and T. Dicu
Radium concentration was determined in 23 types of bottled mineral waters, commercially available in Romania. Using the Lucas
cells with the device Luk 3A, the radium concentration was determined directly, after the radon balanced with radium. From
these measurements, the corresponding annual effective ingestion dose was determined.
Authors:D. Ruppert, Ph. Hopke, P. Clute, W. Metzger, and D. Crowley
In order to describe the occurrence and to investigate the sources of arsenic found in Chautauqua Lake sediments, 98 grab
samples have been analyzed by neutron activation analysis. The arsenic concentrations were found to range from <0.5 to 58.75
ppm for 96 of the 98 samples with an overall average value of 22.10 ppm. The two other samples had concentrations of 140.0
and 306.0 ppm. High arsenic concentrations have been positively correlated with a decrease in the sediment particle size.
Natural arsenic concentrations found in the soil and bedrock in the area do not explaint the observed concentrations in the
lake sediment. The increase in arsenic appears to be related to the spraying of sodium arsenite as an aquatic pesticide during
the period 1955–1963.
Beryllium-7 (7Be) activity in maize was measured in Yangling County, Shaanxi Province, on the Loess Plateau Region of China in 2007. The
7Be mass activity concentration in maize leaf samples was significantly greater than in maize stem, maize root and maize grain
samples. The 7Be activity in maize leaves accounted for 78% of the total maize 7Be activity. The 7Be mass activity concentration in maize varied from 25.4 to 122.4 Bq kg−1 and areal activity concentration held by maize from 1.2 to 111.5 Bq m−2 during the growth period. The percentage of 7Be areal activity concentration held by maize relative to the 7Be areal activity concentration measured in reference soils ranged from 0.4 to 24.2% with a mean of 13.7%.
Authors:P. Mahawatte, K. R. Dissanayaka, and R. Hewamanna
Elemental concentration of nineteen Ayurvedic drugs have been measured using energy dispersive X-ray fluorescence analysis.
Concentrations of nineteen elements: Si, P, S, Cl, K, Ca, Ti, Cr, Mn, Fe Ni, Cu, Zn, As, Br, Rb, Sr, Zr and Hg have been determined
using emission transmission method with Mo target. K, Ca and Fe were detected in all samples and their concentrations ranged
from 0.35-2.88%, 0.346-8.65% and 0.007-36.7%, respectively. Maximum concentration measured in other elements ranged from 0.006%
to 40.7%. The multi element and non-destructive nature of the method offers a simple way to establish the quality of the drugs
that contain heavy metals in considerable concentration.
Authors:T. Iyogi, S. Ueda, S. Hisamatsu, K. Kondo, H. Haruta, H. Katagiri, M. Kurabayashi, Y. Nakamura, and N. Tsuji
To obtain an average dose from 222Rn to the people in Aomori Prefecture where the first Japan"s nuclear fuel cycling facilities are now under construction, we surveyed 222Rn concentrations in 109 dwellings in the Prefecture from 1992 to 1996. The outdoor 222Rn concentrations were also measured in gardens of 15 dwellings. The 222Rn concentrations were measured with passive 222Rn detectors which used a polycarbonate film for counting a-ray and could separate concentrations of 222Rn from 220Rn. Counting efficiencies of the detectors were calibrated with a standard 222Rn chamber in the Environmental Measurement Laboratory in USA and in the National Radiological Protection Board in UK. Geometric means of 222Rn concentration were 13 and 4.4 Bq.m-3 in the dwellings and outdoor, respectively. These values were consistent to nationwide survey results in Japan. The 222Rn concentrations in the dwellings depended on their age. The concentrations were higher in recent dwellings than in older ones. The radiation dose from 222Rn was estimated, taking into account the occupancy factor for inside and outside of dwellings. The annual dose was 0.32 mSv.y-1, and 99% of the dose came from the exposure to 222Rn inside the dwelling.
A radiometric method, for the determination of PEG-1000 based on the extraction of an associate Ba2+-PEG-chlorinated dicarbolide anion /[/C2B9H8Cl3/2Co]–, further abbreviated BCl–/ into a mixture nitrobenzene + chloroform /41/, has been alaborated. The activity of133Ba which is used as a radioactive indicator, is proportional to the PEG-1000 concentration in the sample. The optimum conditions for the determination of PEG-1000 /e.g. the acidity of the solution, the barium concentration, the concentration of the extraction agent etc./ have been studied in detail.
Authors:Miguel Salas-Luevano, Eduardo Manzanares-Acuña, Consuelo Letechipia-de Leon, Víctor Hernandez-Davila, and Hector Vega-Carrillo
Lead concentration in soils has been measured in Vetagrande, an old mining town located at the state of Zacatecas in México.
Eighty nine soils samples were analyzed using Energy Dispersive X-ray Fluorescence. The lead concentrations were treated with
the Kriging method in order to estimate the lead concentration distribution in the studied area. Pb levels in soils were from
8 to 7730 μg kg−1, where 28.1% of soil samples have less than 400 μg kg−1, 71.9% is above 400 μg kg−1 which is the maximum level recommended by the EPA for residential use of soil. Lead concentration measured around public
sites represent a risk of lead intake in the population.
Authors:M. Sultana, A. Toyoshima, A. Mito, N. Takahashi, H. Baba, and H. Watarai
The solvent extraction behavior of radioiodine at tracer concentration was studied by varying the pH of the tracer solution in order to gain deeper insight into the anomalous behavior of radioiodine at low concentrations. The anomalous behavior of radioiodine was observed with all the tracer solutions because of the existence of radioiodine complex in the tracer solution. The observed anomalous behavior of radioiodine was consistently explained by the comprehensive extraction mechanism.
Nuclear microanalysis has been applied for the determination of in-depth concentration profiles of nitrogen in oxy-nitrided
high-speed steel. The concentration profiles were deduced from measurements of the nitrogen content, determined by means of
the14N(d, α)12C reaction, for the set of initially identical samples after the removal of surface layers of sequentially increasing thicknesses.
Strong blocking of the nitrogen diffusion due to the presence of oxygen has been observed.
Authors:C. C. Dantas, R. Narain, V. A. dos Santos, and A. C. B. A. Melo
The axial and radial distribution of the catalyst concentration, in the riser of an EMC - experimental cold model of a fluid
catalytic cracking type unit, was measured by gamma-absorption. The solid concentration in the circulating fluidized bed was
determined by measurements with a 241Am gamma-source and a NaI(Tl) detector. The operation, instrumental measurements and data acquisition system of the cold unit
were automated. The catalyst concentration measurements were carried out in static experiments and in the circulating fluidized
bed. A calibration of the distribution concentration was made with experimental data from gas velocity and pressure drop along
the riser that gave the best multi-regression model. A spatial resolution of 5.0 . 10-3 m by scanning the riser and a catalyst density resolution of 5.0±0.8 kg/m3 were obtained. The axial catalyst concentration distribution, in the 5-13 kg/m 3 interval, showed a predicted pattern according to the literature. The radial distribution was in an annular configuration
for this diluted catalyst concentration.