Journal of Geophysical Research: Atmospheres, 2024
The objectives of the current study are to carry out soil gas radon (Rn) measurements, to evaluat... more The objectives of the current study are to carry out soil gas radon (Rn) measurements, to evaluate the total inhalation effective dose, to determine risk levels over the lithological formations of the study area. The behavior investigation of Rn activity concentration distributions in dwellings and soils, and soil Rn mapping were also conducted. Soil gas Rn measurements were made at 102 sampling points by Markus 10 instrument. This data was combined with previously reported results from 140 indoor Rn RADTRAK dosimeters to determine the total inhalation effective dose and to conduct a statistical analysis. Overall, the Rn activity concentrations in soil and dwellings range from 4 to 66 kBq m 3 and from 15 to 140 Bq m 3 , with averages of 31 ± 15 kBq m 3 and 41 ± 24 Bq m 3 respectively. The corresponding total inhalation effective dose ranges from 0.35 to 3.53 mSv y 1 , with a mean value of 1.37 ± 0.58 mSv y 1. For soil gas Rn, the chlorite schist lithology showed the highest average concentration level. Which could be justified by the possible presence, within chlorite minerals, highly emitting zones of alpha particles, leading to the formation of radioactive halos. Normal and high-risk level of Rn were found for about 82% and 11% of the total area surveyed respectively. These findings highlight the need for preventive measure against Rn exposure in homes within the investigated areas. This study contributes valuable insights into Rn distribution patterns and risk assessment, offering a basis for targeted interventions in the region. Plain Language Summary Radon (222 Rn (Rn or radon)) is the ubiquitous natural radioactive gas in the earth's crust. It is responsible for about 50% of the total dose received by the public from exposure to natural ionizing radiation. This gas have been recognized as the second leading cause of lung cancer in the world. The current work objectives are to measure the soil gas Rn activity concentrations, to assess the total inhalation dose received by the public and to determine risk levels of various lithological formations. In general, we found that the chlorite schist lithology had the highest average concentration level, due to the presence of minerals such as biotite and chlorite. Public exposure to Rn is greater indoors than outdoors with average inhalation dose relatively higher than the worldwide average. This is due to the numerous factors such as type of construction, building materials, low indoor air renewal rates, etc. The whole study area surveyed were classified as normalrisk zones. These results reveal that preventive and protective measures against the public exposure to Rn are required from the construction of dwellings. Based on the activity concentrations distribution model and risk assessment, areas that could be targeted for potential intervention could be identified. 2. Materials and Methods 2.1. Physical and Geological Setting of the Study Area The study area covers the localities of Yaoundé, Okola, Monatele, Obala, and Mbalmayo in the Center Region of Cameroon, spanning, latitudes 3°10′00″ to 4°30′00″N and longitudes 11°10′00″ to 12°0′00″E. This region belongs to the classic sub-equatorial Guinean climate which is characterized by alternating (regular succession) of
International Journal of Engineering and Applied Physics (IJEAP), 2024
Cadmium Selenide thin films were deposited on glass substrates and p-type silicon substrates usin... more Cadmium Selenide thin films were deposited on glass substrates and p-type silicon substrates using pulsed laser deposition technique (Nd: YAG laser). Some of these samples were exposed to different intervals (10,20,30,40) days of gamma radiation using a 226 Ra source emitting 186 KeV γ-ray. For comparison purposes, the other diodes were kept without any irradiation. Results have shown all these thin films exhibit a hexagonal structure. However, there is a new (102-SiO2) peak appeared in the irradiated thin film pattern. The crystallite size of pristine and irradiated CdSe thin films were (26.9,25.8,28.4,35.3 and 22.2) nm respectively, whereas the average grain size of the pristine film was (112.3-29.24) nm whereas for the irradiated films (45.58-33.72) nm, (61.16-42.8) nm, (55.7-36.03) nm and (53.31-43.45) nm. Results also show that the band gap increased from 2.17eV for pristine thin films to 2.28, 2.45, 2.2, and 2.28 eV for the irradiated thin films. also, I-V characteristics show the dark current decreases for the irradiated thin films. The forward current under illumination increases when exposed to small gamma radiation values and then decreases with higher exposure values. In contrast, the reverse current increases with the irradiation.
The present work aims to detect the effects of gamma ray radiation emitted from Co-60 on several ... more The present work aims to detect the effects of gamma ray radiation emitted from Co-60 on several blood parameters (PCV, Hb, WBCs and RBCs) of male chickens. Also, the potential antioxidant impact of grape seeds oil exposed to cold plasma as a protective material to lower the damage caused by gamma ray was tested for a long time and low dose rate. Healthy male chickens were used in this study which had an age range of 2 to 3 months and a weight range of 1.5 to 2 kg. Animals were kept in plastic cages (100 x 400 x 40 cm dimensions) within humidity and temperature preserved at limited values. Four experimental groups were included; the first was the un-exposed control. The second group was administered with a dose of grape seed extract. The third group was exposed to gamma ray radiation only. The fourth group was administered with a dose of grape seed extract and irradiated with gamma waves. Forty male chickens were used in this work as they were parted and administered with the selected doses. The control group was considered as the first group that contained 10 male chicken without being exposed to waves of gamma rays. The next group also contained 10 male chicken irradiated with 5 Gy/lh at interval 7 hour/day for 20 days as second group. Another group contained 10 male chicken and was dealt with oil of grape seed 400 mg/kg wt) with orally administered dose for 20 days as third group. The fourth group contained 10 male chicken irradiated with 5 Gy/h at interval of 7 hour/day for 20 days and dealt with orally administered dose (400 mg/kg wt) of grape seed oil for the same time. Overall groups (2-4), male chicken number became 30 used for 40.60 days at 7 hours per day. The schedule of work was achieved at 5 Gy/h of radiation equivalent dose with different exposure time for (20 and 40,60 days) on male chicken and at period 7 hours daily. The grape seed extract was bought from local market in Mosul City and filters from impure, as we found significant decrease in ratio of blood factors RBCs, WBCs, Hb and PCV with increasing of exposure time. This data changes with adding antioxidant materials as (grape seed oil) were the value of blood factors ratio enhancement by increasing the time of dose of these material compared with control group. The blood factors ratio of male chickens change with exposure time, with significant decrease by increasing exposure time, however, the protective material (grape seed oil) reduces the change in ratio % of the some blood factors compared with control group.
Due to the effect it has on the chick version, fertility is a hot concern in the broiler industry... more Due to the effect it has on the chick version, fertility is a hot concern in the broiler industry. In flocks that are generally matted, the relationship between fertility and development is inverse. (Chambers,1990) selecting multiples for growth or development from a selection of options.
Int. J. Nuclear Energy Science and Technology, 2023
Gamma spectroscopic technique with NaI(Tl) was used to measure uranium activity in well-water sam... more Gamma spectroscopic technique with NaI(Tl) was used to measure uranium activity in well-water samples collected from the Nineveh Governorate in northern Iraq. The obtained results determined chemical toxic and radiological risks to humans through uranium content, either carcinogenic or non-carcinogenic, during lifetime utilisation by the population in the region. The activity of uranium ranged from 1.09 to 4.86 Bq.L-1. The radiological risks for excess cancer mortality fluctuate between 4.09 × 10-5 and 1.82 × 10-4 , while those for cancer morbidity risk range from 6.26 × 10-5 to 2.79 × 10-4. The measured lifetime average daily dose ranged from 1.20 μg.kg-1 day-1 to 5.37 μg.kg-1 day-1. All samples are clearly below the recommended value (4.53 μg.kg-1 day-1) except sample (W12). The current research may be of imperative significance in radioactive epidemiological evaluation, diagnosis and forecast of uranium infections within the current region.
ARO-The Scientific Journal of Koya University, 2023
The fundamental goal of this study is to measure the level of radioactivity in the soil of the ar... more The fundamental goal of this study is to measure the level of radioactivity in the soil of the area around Al-Hadbaa cement plant, also to evaluate the radiological hazard of radionuclide, gamma-spectroscopy with an HPGe detector with the crystal diameter of 70.6 mm and length of 70 mm has been used to estimate the specific activity of natural radionuclides 226 Ra, 232 Th, 40 K, and artificial radionuclides 137 Cs in the fifteen soil samples collected. The results show that the average concentration of specific activity of 226 Ra, 232 Th, 40 K, and 137 Cs was 11.17 ± 1.69, 13.38 ± 0.72, 158.36 ± 5.35 Bq/kg, and 1.52 ± 0.19 Bq/kg, respectively. The average specific activity of these radionuclides is discovered to be lower than the global average which is 33 Bq/kg for 226 Ra, 30 Bq/kg for 232 Th, and 400 Bq/kg for 40 K. Radiological hazard indices are determined according to the activity concentration of the radionuclides in the area under study. The outcome of the radiological hazard index is within the globally recognized limit proposed by UNSCEAR which is 1000 μSv/y for annual effective dose and 290 × 10-6 for cancer risk, so it is possible to conclude that there are no radiological hazards as a result of radiation exposure to the workers working in the cement plant as well as the organisms living in the region.
To cite this article: Taha Yaseen Wais et al 2023 Phys. Scr. 98 065304 View the article online fo... more To cite this article: Taha Yaseen Wais et al 2023 Phys. Scr. 98 065304 View the article online for updates and enhancements. You may also like Radioactivity of residues from waste incineration facilities in Finland Antti Kallio, Sinikka Virtanen, Niina Leikoski et al.-Estimated the concentration of 238 U, 232 Th and 40 K in flour samples of Iraq markets Shaymaa Awad Kadhim, Shatha F. Alhous, Ahmed Shaker Hussein et al.-Assessement of doses to members of the public arising from the use of ornamental rocks in residences André Luiz do Carmo Leal and Dejanira da Costa Lauria
In this paper, four samples of some binary and triple alloys (Al, Cu, Pb) have been studied theor... more In this paper, four samples of some binary and triple alloys (Al, Cu, Pb) have been studied theoretically and experimentally. For the gamma rays shielding parameters, a good agreement was observed between the theoretical and experimental values for each of mass attenuation coefficient (), half-value layers (HVL), mean free path (MFP) the radiation protection efficiency (RPE) of the samples. The theoretical measurements were carried out using XCOM program in the energy range from 1 keV to 100 GeV, and practical values for 662, 1173, and 1332 keV gamma-ray energies of 137 Cs and 60 Co radiation sourcesusing NaI (Tl) detector.
Transfer factors of 226Ra, 232Th and 40K from fertilised soil to different types of field crops in Tikrit city, Iraq, 2022
Natural radionuclide activity concentrations in fertilised soil and field crops, as well as the t... more Natural radionuclide activity concentrations in fertilised soil and field crops, as well as the transfer factor from fertilised soil to field crops, were measured. The measurements were carried out using gamma ray spectroscopy with a Nal(TI) detector. The geometric mean (geometric standard deviation) for soil-to-crop transfer factors for each study site were 0.57(1.37), 0.41(1.53) and 0.41(1.51) for 226 Ra, 232 Th and 40 K, respectively. The geometric mean transfer factor of 232 Th in the present study is 19 times higher than the world mean value, whereas the geometric mean transfer factors of 226 Ra and 40 K are less. The results show that the fertilised soil samples and field crops pose no radioactive risk and that there are no immediate health risks associated with the use of these samples in the areas under investigation. Furthermore, there was no correlation between 232 Th and 226 Ra concentrations, possibly because these radionuclides are transported differently in soil.
International Journal of Environmental Analytical Chemistry, 2023
In the present work, radioactivity level in 15 collected soil samples from the area around fertil... more In the present work, radioactivity level in 15 collected soil samples from the area around fertiliser factory in Upper Egypt has been measured using gamma ray Spectrometry due to radionuclides occurred naturally namely 226 Ra, 232 Th and 40 K to study the concentrations of these nuclides in this soil and determine the effect of Assuit fertiliser factory exhaust on radiological contents of surrounding Soil Samples in Assuit Province, Egypt. Activity concentrations of 226 Ra, 232 Th and 40 K for soil samples were measured by scintillation detector NaI (Tl), has recorded average values 49.45 ± 5.04, 59.113 ± 2.96 and 137.85 ± 6.89 Bq/kg, respectively. On the other hand the average value of radiological hazards affected on farmers and populations were 150.32 Bq/kg, 64.3 nG/h, 0.257, 0.544, 1.006, 0.246, 0.315 and 0.0788 mSv/y for radium equivalent activity, absorbed gamma dose, external and internal hazard indices, gamma index, indoor and outdoor effective dose, respectively. The absorbed dose, gamma index and the annual gonadal dose equivalent the radiological hazards were found higher than permissible level.
Heavy metals are defined as a subgroup of those elements that exhibit metallic properties. They i... more Heavy metals are defined as a subgroup of those elements that exhibit metallic properties. They include transition metals, some metals, lanthanides, and actinides, using density as a distinguishing factor (Suciu et al., 2008). Heavy metal pollution has become a global problem, as heavy metals are inorganic pollutants of a non-degradable nature and often accumulate at increasing levels, which leads to or causes harmful biological effects (Jain, 1979). Heavy metals are pollutants capable of causing environmental and health problems in the water, soil, atmosphere, and microorganisms (Navarro et al., 2008). Heavy metals deposited into a river system by natural or anthropogenic sources are dispersed between the aqueous phase and the bed sediments during transportation (Sin et al., 2001). Only a small part of free metal ions remains dissolved in water due to adsorption, hydrolysis, and co-precipitation, whereas many of them are deposited in sediment (Gaur et al., 2005). Sediments are ecologically significant Article Info
INTERNATIONAL JOURNAL OF ENVIRONMENTAL ANALYTICAL CHEMISTRY, 2022
The essential objective of this study was to estimate 222Rn, 238U, and
226Ra concentrations of pl... more The essential objective of this study was to estimate 222Rn, 238U, and 226Ra concentrations of plankton samples, along with the risk indices defined by PAEC, Ep, AED and CPPP. These analyzes were carried out on plankton samples from fifteen-alley air conditioner filters in the old Mosul area. In this analysis, using the cumulative monitoring technique of the PM-355 nuclear track detector. The maximum concentrations of radon, uranium, radium and risk indices were observed in Bableksh (sample 5) alley at 77.77(Bq. m−3), 3.74(ppm), 21.46(Bq. kg−1), 0.0084(mWL), 0.3465(WLMY−1), 1.962(mSv.y−1), and 35.31(per 106person). Whereas at Al Hadhira alley the minimum was found to be 39.07(Bq.m−3), 2.05(ppm), (10.78 Bq.kg−1), 0.00422(mWL), 0.1741 (WLMY−1), 0.9856 (mSv.y−1), and 17.74(per106 person. The average concentrations of radon, uranium, radium and, risk indices of all studied alleys were 59.156 � 10.7 (Bq. m−3), 2.803(ppm) � 0.48, 16.34 � 4.49(Bq.kg−1), 0.00646((mWL)) � 0:00011, 0.2662 (WLMY−1) ±0:0517, 1.506 (mSv.y−1)±0:279, and 27.116 (per 106person)±5:043, respectively. Alpha indexes were estimated for all surveyed alleys, in addition to the radioactivity tests and the risk indices. Their values varied between 0.053 and 0.107, with an average 0.081 � 0.0021. Such levels are significantly smaller than the total dose given by the United Nations Scientific Committee on the effects of atomic radiation, especially at Exposure to 222Rn progeny (Ep) which is within the range of 0.2–10 mSv.y−1 (UNSCEAR). Appropriate correlations between radon concentration with uranium and radium concentration (R2 = 0.8739 and 0.896) have been identified, respectively. The results revealed that the amount of background radioactivity of the alleys of old Mosul area would be within acceptable limits.
The fundamental goal of the current study is to determine the mean activity concentrations of nat... more The fundamental goal of the current study is to determine the mean activity concentrations of natural and artificial radionuclides of 226 Ra, 232 Th, 40 K, and 137 Cs using gamma spectrometry for three locations, in Egypt, Saudi Arabia, and Iraq, which are significant and vital countries in the Middle East. The mean absorbed dose rate equals 22.35, 28.96, and 43.34 nGy h-1 for Egypt, Saudi Arabia, and Iraq. The results are consistent with international reports. The dose contribution percentages for investigated locations are 24 %, 30 %, and 46 % for Egypt, Saudi Arabia, and Iraq, respectively. The obtained results were clarified by statistical measurements using one-way ANOVA test to determine the distribution and differences between the averages of the three groups under study, as they may be influenced by geological variations and human intervention. It was found that the Iraq samples followed a symmetrical, standard normal distribution, while samples from Egypt and Saudi Arabia did not. Statistically significant differences were found between the data from the three countries.
Journal of Radiation and Nuclear Applications, 2021
Dynamic Deformation Model (DDM) has been employed to study the nuclear structure of 154−156 Gd is... more Dynamic Deformation Model (DDM) has been employed to study the nuclear structure of 154−156 Gd isotopes. The energy levels, electromagnetic transition properties , , and the mixing ratios for transitions δ (E2/M1) are studied; the various static and dynamic shape characteristic for these isotopes are discussed. The results obtained for 154−156 Gd isotopes are reasonably in a good agreement with the known experimental results.
In this study, the specific activity was identified in 12 fertilizer samples using a gamma spectr... more In this study, the specific activity was identified in 12 fertilizer samples using a gamma spectroscopy, and the results showed that the average specific activity of natural radionuclides (226 Ra, 232 Th, 40 K) was 36.24 ± 0.767 Bq/kg, 55.40 ± 0.973 Bq/kg, and 202.87 ± 5.062 Bq/kg, respectively, where the average specific activity of 226 Ra and 232 Th exceeded the globally recommended limits, while the average specific activity of 40 K was within the internationally recommended limits by UNSCEAR. The radium equivalent Ra eq , absorbed dose rate in air D c , annual effective dose equivalent for indoor and outdoor exposure (AEDE indoor and AEDE outdoor), excess lifetime cancer risk ELCR, internal and external hazard indicators (H in and H ex) and gamma representative level index were calculated. The results of most samples were within the global average recommended by UNSCEAR, so it is safe to consume and does not pose a threat to the general public.
Journal of Geophysical Research: Atmospheres, 2024
The objectives of the current study are to carry out soil gas radon (Rn) measurements, to evaluat... more The objectives of the current study are to carry out soil gas radon (Rn) measurements, to evaluate the total inhalation effective dose, to determine risk levels over the lithological formations of the study area. The behavior investigation of Rn activity concentration distributions in dwellings and soils, and soil Rn mapping were also conducted. Soil gas Rn measurements were made at 102 sampling points by Markus 10 instrument. This data was combined with previously reported results from 140 indoor Rn RADTRAK dosimeters to determine the total inhalation effective dose and to conduct a statistical analysis. Overall, the Rn activity concentrations in soil and dwellings range from 4 to 66 kBq m 3 and from 15 to 140 Bq m 3 , with averages of 31 ± 15 kBq m 3 and 41 ± 24 Bq m 3 respectively. The corresponding total inhalation effective dose ranges from 0.35 to 3.53 mSv y 1 , with a mean value of 1.37 ± 0.58 mSv y 1. For soil gas Rn, the chlorite schist lithology showed the highest average concentration level. Which could be justified by the possible presence, within chlorite minerals, highly emitting zones of alpha particles, leading to the formation of radioactive halos. Normal and high-risk level of Rn were found for about 82% and 11% of the total area surveyed respectively. These findings highlight the need for preventive measure against Rn exposure in homes within the investigated areas. This study contributes valuable insights into Rn distribution patterns and risk assessment, offering a basis for targeted interventions in the region. Plain Language Summary Radon (222 Rn (Rn or radon)) is the ubiquitous natural radioactive gas in the earth's crust. It is responsible for about 50% of the total dose received by the public from exposure to natural ionizing radiation. This gas have been recognized as the second leading cause of lung cancer in the world. The current work objectives are to measure the soil gas Rn activity concentrations, to assess the total inhalation dose received by the public and to determine risk levels of various lithological formations. In general, we found that the chlorite schist lithology had the highest average concentration level, due to the presence of minerals such as biotite and chlorite. Public exposure to Rn is greater indoors than outdoors with average inhalation dose relatively higher than the worldwide average. This is due to the numerous factors such as type of construction, building materials, low indoor air renewal rates, etc. The whole study area surveyed were classified as normalrisk zones. These results reveal that preventive and protective measures against the public exposure to Rn are required from the construction of dwellings. Based on the activity concentrations distribution model and risk assessment, areas that could be targeted for potential intervention could be identified. 2. Materials and Methods 2.1. Physical and Geological Setting of the Study Area The study area covers the localities of Yaoundé, Okola, Monatele, Obala, and Mbalmayo in the Center Region of Cameroon, spanning, latitudes 3°10′00″ to 4°30′00″N and longitudes 11°10′00″ to 12°0′00″E. This region belongs to the classic sub-equatorial Guinean climate which is characterized by alternating (regular succession) of
International Journal of Engineering and Applied Physics (IJEAP), 2024
Cadmium Selenide thin films were deposited on glass substrates and p-type silicon substrates usin... more Cadmium Selenide thin films were deposited on glass substrates and p-type silicon substrates using pulsed laser deposition technique (Nd: YAG laser). Some of these samples were exposed to different intervals (10,20,30,40) days of gamma radiation using a 226 Ra source emitting 186 KeV γ-ray. For comparison purposes, the other diodes were kept without any irradiation. Results have shown all these thin films exhibit a hexagonal structure. However, there is a new (102-SiO2) peak appeared in the irradiated thin film pattern. The crystallite size of pristine and irradiated CdSe thin films were (26.9,25.8,28.4,35.3 and 22.2) nm respectively, whereas the average grain size of the pristine film was (112.3-29.24) nm whereas for the irradiated films (45.58-33.72) nm, (61.16-42.8) nm, (55.7-36.03) nm and (53.31-43.45) nm. Results also show that the band gap increased from 2.17eV for pristine thin films to 2.28, 2.45, 2.2, and 2.28 eV for the irradiated thin films. also, I-V characteristics show the dark current decreases for the irradiated thin films. The forward current under illumination increases when exposed to small gamma radiation values and then decreases with higher exposure values. In contrast, the reverse current increases with the irradiation.
The present work aims to detect the effects of gamma ray radiation emitted from Co-60 on several ... more The present work aims to detect the effects of gamma ray radiation emitted from Co-60 on several blood parameters (PCV, Hb, WBCs and RBCs) of male chickens. Also, the potential antioxidant impact of grape seeds oil exposed to cold plasma as a protective material to lower the damage caused by gamma ray was tested for a long time and low dose rate. Healthy male chickens were used in this study which had an age range of 2 to 3 months and a weight range of 1.5 to 2 kg. Animals were kept in plastic cages (100 x 400 x 40 cm dimensions) within humidity and temperature preserved at limited values. Four experimental groups were included; the first was the un-exposed control. The second group was administered with a dose of grape seed extract. The third group was exposed to gamma ray radiation only. The fourth group was administered with a dose of grape seed extract and irradiated with gamma waves. Forty male chickens were used in this work as they were parted and administered with the selected doses. The control group was considered as the first group that contained 10 male chicken without being exposed to waves of gamma rays. The next group also contained 10 male chicken irradiated with 5 Gy/lh at interval 7 hour/day for 20 days as second group. Another group contained 10 male chicken and was dealt with oil of grape seed 400 mg/kg wt) with orally administered dose for 20 days as third group. The fourth group contained 10 male chicken irradiated with 5 Gy/h at interval of 7 hour/day for 20 days and dealt with orally administered dose (400 mg/kg wt) of grape seed oil for the same time. Overall groups (2-4), male chicken number became 30 used for 40.60 days at 7 hours per day. The schedule of work was achieved at 5 Gy/h of radiation equivalent dose with different exposure time for (20 and 40,60 days) on male chicken and at period 7 hours daily. The grape seed extract was bought from local market in Mosul City and filters from impure, as we found significant decrease in ratio of blood factors RBCs, WBCs, Hb and PCV with increasing of exposure time. This data changes with adding antioxidant materials as (grape seed oil) were the value of blood factors ratio enhancement by increasing the time of dose of these material compared with control group. The blood factors ratio of male chickens change with exposure time, with significant decrease by increasing exposure time, however, the protective material (grape seed oil) reduces the change in ratio % of the some blood factors compared with control group.
Due to the effect it has on the chick version, fertility is a hot concern in the broiler industry... more Due to the effect it has on the chick version, fertility is a hot concern in the broiler industry. In flocks that are generally matted, the relationship between fertility and development is inverse. (Chambers,1990) selecting multiples for growth or development from a selection of options.
Int. J. Nuclear Energy Science and Technology, 2023
Gamma spectroscopic technique with NaI(Tl) was used to measure uranium activity in well-water sam... more Gamma spectroscopic technique with NaI(Tl) was used to measure uranium activity in well-water samples collected from the Nineveh Governorate in northern Iraq. The obtained results determined chemical toxic and radiological risks to humans through uranium content, either carcinogenic or non-carcinogenic, during lifetime utilisation by the population in the region. The activity of uranium ranged from 1.09 to 4.86 Bq.L-1. The radiological risks for excess cancer mortality fluctuate between 4.09 × 10-5 and 1.82 × 10-4 , while those for cancer morbidity risk range from 6.26 × 10-5 to 2.79 × 10-4. The measured lifetime average daily dose ranged from 1.20 μg.kg-1 day-1 to 5.37 μg.kg-1 day-1. All samples are clearly below the recommended value (4.53 μg.kg-1 day-1) except sample (W12). The current research may be of imperative significance in radioactive epidemiological evaluation, diagnosis and forecast of uranium infections within the current region.
ARO-The Scientific Journal of Koya University, 2023
The fundamental goal of this study is to measure the level of radioactivity in the soil of the ar... more The fundamental goal of this study is to measure the level of radioactivity in the soil of the area around Al-Hadbaa cement plant, also to evaluate the radiological hazard of radionuclide, gamma-spectroscopy with an HPGe detector with the crystal diameter of 70.6 mm and length of 70 mm has been used to estimate the specific activity of natural radionuclides 226 Ra, 232 Th, 40 K, and artificial radionuclides 137 Cs in the fifteen soil samples collected. The results show that the average concentration of specific activity of 226 Ra, 232 Th, 40 K, and 137 Cs was 11.17 ± 1.69, 13.38 ± 0.72, 158.36 ± 5.35 Bq/kg, and 1.52 ± 0.19 Bq/kg, respectively. The average specific activity of these radionuclides is discovered to be lower than the global average which is 33 Bq/kg for 226 Ra, 30 Bq/kg for 232 Th, and 400 Bq/kg for 40 K. Radiological hazard indices are determined according to the activity concentration of the radionuclides in the area under study. The outcome of the radiological hazard index is within the globally recognized limit proposed by UNSCEAR which is 1000 μSv/y for annual effective dose and 290 × 10-6 for cancer risk, so it is possible to conclude that there are no radiological hazards as a result of radiation exposure to the workers working in the cement plant as well as the organisms living in the region.
To cite this article: Taha Yaseen Wais et al 2023 Phys. Scr. 98 065304 View the article online fo... more To cite this article: Taha Yaseen Wais et al 2023 Phys. Scr. 98 065304 View the article online for updates and enhancements. You may also like Radioactivity of residues from waste incineration facilities in Finland Antti Kallio, Sinikka Virtanen, Niina Leikoski et al.-Estimated the concentration of 238 U, 232 Th and 40 K in flour samples of Iraq markets Shaymaa Awad Kadhim, Shatha F. Alhous, Ahmed Shaker Hussein et al.-Assessement of doses to members of the public arising from the use of ornamental rocks in residences André Luiz do Carmo Leal and Dejanira da Costa Lauria
In this paper, four samples of some binary and triple alloys (Al, Cu, Pb) have been studied theor... more In this paper, four samples of some binary and triple alloys (Al, Cu, Pb) have been studied theoretically and experimentally. For the gamma rays shielding parameters, a good agreement was observed between the theoretical and experimental values for each of mass attenuation coefficient (), half-value layers (HVL), mean free path (MFP) the radiation protection efficiency (RPE) of the samples. The theoretical measurements were carried out using XCOM program in the energy range from 1 keV to 100 GeV, and practical values for 662, 1173, and 1332 keV gamma-ray energies of 137 Cs and 60 Co radiation sourcesusing NaI (Tl) detector.
Transfer factors of 226Ra, 232Th and 40K from fertilised soil to different types of field crops in Tikrit city, Iraq, 2022
Natural radionuclide activity concentrations in fertilised soil and field crops, as well as the t... more Natural radionuclide activity concentrations in fertilised soil and field crops, as well as the transfer factor from fertilised soil to field crops, were measured. The measurements were carried out using gamma ray spectroscopy with a Nal(TI) detector. The geometric mean (geometric standard deviation) for soil-to-crop transfer factors for each study site were 0.57(1.37), 0.41(1.53) and 0.41(1.51) for 226 Ra, 232 Th and 40 K, respectively. The geometric mean transfer factor of 232 Th in the present study is 19 times higher than the world mean value, whereas the geometric mean transfer factors of 226 Ra and 40 K are less. The results show that the fertilised soil samples and field crops pose no radioactive risk and that there are no immediate health risks associated with the use of these samples in the areas under investigation. Furthermore, there was no correlation between 232 Th and 226 Ra concentrations, possibly because these radionuclides are transported differently in soil.
International Journal of Environmental Analytical Chemistry, 2023
In the present work, radioactivity level in 15 collected soil samples from the area around fertil... more In the present work, radioactivity level in 15 collected soil samples from the area around fertiliser factory in Upper Egypt has been measured using gamma ray Spectrometry due to radionuclides occurred naturally namely 226 Ra, 232 Th and 40 K to study the concentrations of these nuclides in this soil and determine the effect of Assuit fertiliser factory exhaust on radiological contents of surrounding Soil Samples in Assuit Province, Egypt. Activity concentrations of 226 Ra, 232 Th and 40 K for soil samples were measured by scintillation detector NaI (Tl), has recorded average values 49.45 ± 5.04, 59.113 ± 2.96 and 137.85 ± 6.89 Bq/kg, respectively. On the other hand the average value of radiological hazards affected on farmers and populations were 150.32 Bq/kg, 64.3 nG/h, 0.257, 0.544, 1.006, 0.246, 0.315 and 0.0788 mSv/y for radium equivalent activity, absorbed gamma dose, external and internal hazard indices, gamma index, indoor and outdoor effective dose, respectively. The absorbed dose, gamma index and the annual gonadal dose equivalent the radiological hazards were found higher than permissible level.
Heavy metals are defined as a subgroup of those elements that exhibit metallic properties. They i... more Heavy metals are defined as a subgroup of those elements that exhibit metallic properties. They include transition metals, some metals, lanthanides, and actinides, using density as a distinguishing factor (Suciu et al., 2008). Heavy metal pollution has become a global problem, as heavy metals are inorganic pollutants of a non-degradable nature and often accumulate at increasing levels, which leads to or causes harmful biological effects (Jain, 1979). Heavy metals are pollutants capable of causing environmental and health problems in the water, soil, atmosphere, and microorganisms (Navarro et al., 2008). Heavy metals deposited into a river system by natural or anthropogenic sources are dispersed between the aqueous phase and the bed sediments during transportation (Sin et al., 2001). Only a small part of free metal ions remains dissolved in water due to adsorption, hydrolysis, and co-precipitation, whereas many of them are deposited in sediment (Gaur et al., 2005). Sediments are ecologically significant Article Info
INTERNATIONAL JOURNAL OF ENVIRONMENTAL ANALYTICAL CHEMISTRY, 2022
The essential objective of this study was to estimate 222Rn, 238U, and
226Ra concentrations of pl... more The essential objective of this study was to estimate 222Rn, 238U, and 226Ra concentrations of plankton samples, along with the risk indices defined by PAEC, Ep, AED and CPPP. These analyzes were carried out on plankton samples from fifteen-alley air conditioner filters in the old Mosul area. In this analysis, using the cumulative monitoring technique of the PM-355 nuclear track detector. The maximum concentrations of radon, uranium, radium and risk indices were observed in Bableksh (sample 5) alley at 77.77(Bq. m−3), 3.74(ppm), 21.46(Bq. kg−1), 0.0084(mWL), 0.3465(WLMY−1), 1.962(mSv.y−1), and 35.31(per 106person). Whereas at Al Hadhira alley the minimum was found to be 39.07(Bq.m−3), 2.05(ppm), (10.78 Bq.kg−1), 0.00422(mWL), 0.1741 (WLMY−1), 0.9856 (mSv.y−1), and 17.74(per106 person. The average concentrations of radon, uranium, radium and, risk indices of all studied alleys were 59.156 � 10.7 (Bq. m−3), 2.803(ppm) � 0.48, 16.34 � 4.49(Bq.kg−1), 0.00646((mWL)) � 0:00011, 0.2662 (WLMY−1) ±0:0517, 1.506 (mSv.y−1)±0:279, and 27.116 (per 106person)±5:043, respectively. Alpha indexes were estimated for all surveyed alleys, in addition to the radioactivity tests and the risk indices. Their values varied between 0.053 and 0.107, with an average 0.081 � 0.0021. Such levels are significantly smaller than the total dose given by the United Nations Scientific Committee on the effects of atomic radiation, especially at Exposure to 222Rn progeny (Ep) which is within the range of 0.2–10 mSv.y−1 (UNSCEAR). Appropriate correlations between radon concentration with uranium and radium concentration (R2 = 0.8739 and 0.896) have been identified, respectively. The results revealed that the amount of background radioactivity of the alleys of old Mosul area would be within acceptable limits.
The fundamental goal of the current study is to determine the mean activity concentrations of nat... more The fundamental goal of the current study is to determine the mean activity concentrations of natural and artificial radionuclides of 226 Ra, 232 Th, 40 K, and 137 Cs using gamma spectrometry for three locations, in Egypt, Saudi Arabia, and Iraq, which are significant and vital countries in the Middle East. The mean absorbed dose rate equals 22.35, 28.96, and 43.34 nGy h-1 for Egypt, Saudi Arabia, and Iraq. The results are consistent with international reports. The dose contribution percentages for investigated locations are 24 %, 30 %, and 46 % for Egypt, Saudi Arabia, and Iraq, respectively. The obtained results were clarified by statistical measurements using one-way ANOVA test to determine the distribution and differences between the averages of the three groups under study, as they may be influenced by geological variations and human intervention. It was found that the Iraq samples followed a symmetrical, standard normal distribution, while samples from Egypt and Saudi Arabia did not. Statistically significant differences were found between the data from the three countries.
Journal of Radiation and Nuclear Applications, 2021
Dynamic Deformation Model (DDM) has been employed to study the nuclear structure of 154−156 Gd is... more Dynamic Deformation Model (DDM) has been employed to study the nuclear structure of 154−156 Gd isotopes. The energy levels, electromagnetic transition properties , , and the mixing ratios for transitions δ (E2/M1) are studied; the various static and dynamic shape characteristic for these isotopes are discussed. The results obtained for 154−156 Gd isotopes are reasonably in a good agreement with the known experimental results.
In this study, the specific activity was identified in 12 fertilizer samples using a gamma spectr... more In this study, the specific activity was identified in 12 fertilizer samples using a gamma spectroscopy, and the results showed that the average specific activity of natural radionuclides (226 Ra, 232 Th, 40 K) was 36.24 ± 0.767 Bq/kg, 55.40 ± 0.973 Bq/kg, and 202.87 ± 5.062 Bq/kg, respectively, where the average specific activity of 226 Ra and 232 Th exceeded the globally recommended limits, while the average specific activity of 40 K was within the internationally recommended limits by UNSCEAR. The radium equivalent Ra eq , absorbed dose rate in air D c , annual effective dose equivalent for indoor and outdoor exposure (AEDE indoor and AEDE outdoor), excess lifetime cancer risk ELCR, internal and external hazard indicators (H in and H ex) and gamma representative level index were calculated. The results of most samples were within the global average recommended by UNSCEAR, so it is safe to consume and does not pose a threat to the general public.
This study included determine to the ability of some building
materials on the attenuation of gam... more This study included determine to the ability of some building materials on the attenuation of gamma rays by FindLinear andMass Attenuation Coefficients and examination of homogeneity for this materialsby using spectroscopy gamma rays( UCS20) associated with the (NaI (TI)) at energies of gamma rays (81, 356, 662, 1173, 1332) keV which emitted from Sources( 133Ba, 137Cs, 60Co) respectively,were examined homogeneity of materials using a narrow beam mono-energy gamma rays emitted from the source of radioactive 137 Cs (662) keV through a percentage of the difference between the intensity of gamma rays transmission andLinearAttenuation Coefficient in four different locations ofThe material and the percentage of standard deviation,The more material was homogeneous shield was their best on the presence of gaps attenuation through the material leads to increase abilityof radiationof penetration Material,The program used (MATLAB) (version 7.1) in this study for the linear and mass attenuation coefficients curves, which showed that the linear and mass attenuation coefficients less with increaseenergy and also find curves homogeneity test,Thesestudy include different types of building materials because of its importance in the technological and industrial processes.The results showed that among building materials the possessed Granite usedhigher the linearand mass attenuation coefficientTherefore it can be used as a protective shield against radiation,whileAppears Thermstone the less linear attenuation coefficient because of its low-lying density and low concentrations of elements with atomic number of large and this confirms the reliability of the intensity attenuation coefficients under study and shields on the atomic number of its Compounds, andappear Thermstone less homogeneousbecause of The presence of air bubbles punctuated,so Thermstone does not favor in shielding against gamma rays
This study involves the topic of radioactivity in soil of some regions in Nineveh
governorate thr... more This study involves the topic of radioactivity in soil of some regions in Nineveh governorate through measuring radioactivity concentration of radionuclide's in soil samples collected from these regions ,and calculation of some radiological parameters. Gamma ray spectrometers with NaI(Tl) detector system and high purity germanium (HPGe) detector system was used for this purpose. A comparison between obtained results for both systems showed that for the average concentrations of radionuclide's ( 238U, 232Th, 40K , 226Ra and 214Pb) obtained from NaI(Tl) system of these samples was found to be 41.24,21.46, 326.74, 33.55 and 11.76Bq/kg respectively, while it was found that the average concentrations of the same natural radionuclide's obtained from HPGe system (except for uranium 238U which was not obtained from this system) as wells as for the artificial 137Cs radionuclide(232Th, 40K , 226Ra and 214Pb, 137Cs) was found to be 20.30, 378.93, 32.52, 14.78 and 8.17Bq/kg respectively. In order to estimate the radiological hazards to the humans , some of the radiological parameters were calculated ,in which it was found that the average of absorbed dose rate D(nGy/h) is equal to 42.12nGy/h according to NaI(Tl) system,while it was found that it is equal to 43.08nGy/h according to HPGe system ,also annual effective dose equivalent (outdoor) AEDE(Sv/y) was found to be 51.66Sv/y and 52.74Sv/y for NaI(Tl) system and HPGe system respectively, however it was found the same parameter (indoor) is equal to 206.65Sv/y and 211.37Sv/y for the two systems respectively .The average of : radium equivalent Raeq (Bq/kg),gamma index (I) and alpha index (I) was calculated and was found to be 89.41Bq/kg , 90.75Bq/kg and 0.656, 0.656 and 0.167,0.162 for the two systems respectively. The calculation of internal hazard index (Hin) and external hazard index (Hex) was found to be 0.329,0.332 and 0.241,0.244 for the two systems respectively. Also the averages of excess lifetime cancer risk (ELCR) and annual gonadal dose equivalent AGDE(mSv/y) was found to be 180.8210-6, 184.5910-6 and 0.296 mSv/y,0.304 mSv/y for the two systems respectively. Finally it was found that the average exposure dose rate I(R/h) calculated by NaI(Tl) system, was found to be 202.58 R/h.
The aim of the this work was the fabrication and studying the characteristics of a nuclear detect... more The aim of the this work was the fabrication and studying the characteristics of a nuclear detector prepared from p-CdMnTe, of conductivity of ~10-4 (.cm)-1 as grown. Annealing of the samples (2 and 5 hours) changed the conductivity to about (10-7) (.cm)-1, three structures were used, as planar with (Au) ohmic contact on both sides, Second structure as Schottky type structure of In-CdMnTe with (Au) ohmic contact on the back face, and Thirdly MOS device for which the samples annealed under oxygen flow for (2h) at 700 C. These later samples, were only successful samples that produced -ray signals on the MCA. All other samples failed to do so. These samples when connected to conventional nuclear spectroscopy electronics, gave reasonable but not high quality signals due to irradiating with 137Cs, 241Am and (137Cs+ 241Am). Matlab-software based on numerical methods were used to analyze the data. Resolution through (Full Width at Half Maximum), area under the peak and error for this detector were presented. The mobility lifetime product of both electrons and holes for CdMnTe plotted against various gamma energy sources, and then compared with respect to CdZnTe; So there was a clear increase for CdMnTe than CdZnTe.Calculations of transit time, for electrons and holes in CdMnTe, plotted against (1/V) which gave a decrease of the transit time with voltage increase. The quality factor value has been calculated for CdMnTe detector and compared to those of CdZnTe and CdTe detectors only at room temperature. The value of quality factor for CdMnTe detector was higher than the others. Calculations of activation energies of annealed CdMnTe samples for 2 and 5 hours under vacuum (10-5torr) gave 0.361 and 0.270 eV respectively.
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Papers by laith A najam
226Ra concentrations of plankton samples, along with the risk indices
defined by PAEC, Ep, AED and CPPP. These analyzes were carried out
on plankton samples from fifteen-alley air conditioner filters in the
old Mosul area. In this analysis, using the cumulative monitoring
technique of the PM-355 nuclear track detector. The maximum concentrations
of radon, uranium, radium and risk indices were observed
in Bableksh (sample 5) alley at 77.77(Bq. m−3), 3.74(ppm), 21.46(Bq.
kg−1), 0.0084(mWL), 0.3465(WLMY−1), 1.962(mSv.y−1), and 35.31(per
106person). Whereas at Al Hadhira alley the minimum was found to
be 39.07(Bq.m−3), 2.05(ppm), (10.78 Bq.kg−1), 0.00422(mWL), 0.1741
(WLMY−1), 0.9856 (mSv.y−1), and 17.74(per106 person. The average
concentrations of radon, uranium, radium and, risk indices of all
studied alleys were 59.156 � 10.7 (Bq. m−3), 2.803(ppm) � 0.48,
16.34 � 4.49(Bq.kg−1), 0.00646((mWL)) � 0:00011, 0.2662 (WLMY−1)
±0:0517, 1.506 (mSv.y−1)±0:279, and 27.116 (per 106person)±5:043,
respectively. Alpha indexes were estimated for all surveyed alleys, in
addition to the radioactivity tests and the risk indices. Their values
varied between 0.053 and 0.107, with an average 0.081 � 0.0021.
Such levels are significantly smaller than the total dose given by the
United Nations Scientific Committee on the effects of atomic radiation,
especially at Exposure to 222Rn progeny (Ep) which is within the
range of 0.2–10 mSv.y−1 (UNSCEAR). Appropriate correlations
between radon concentration with uranium and radium concentration
(R2 = 0.8739 and 0.896) have been identified, respectively. The
results revealed that the amount of background radioactivity of the
alleys of old Mosul area would be within acceptable limits.
226Ra concentrations of plankton samples, along with the risk indices
defined by PAEC, Ep, AED and CPPP. These analyzes were carried out
on plankton samples from fifteen-alley air conditioner filters in the
old Mosul area. In this analysis, using the cumulative monitoring
technique of the PM-355 nuclear track detector. The maximum concentrations
of radon, uranium, radium and risk indices were observed
in Bableksh (sample 5) alley at 77.77(Bq. m−3), 3.74(ppm), 21.46(Bq.
kg−1), 0.0084(mWL), 0.3465(WLMY−1), 1.962(mSv.y−1), and 35.31(per
106person). Whereas at Al Hadhira alley the minimum was found to
be 39.07(Bq.m−3), 2.05(ppm), (10.78 Bq.kg−1), 0.00422(mWL), 0.1741
(WLMY−1), 0.9856 (mSv.y−1), and 17.74(per106 person. The average
concentrations of radon, uranium, radium and, risk indices of all
studied alleys were 59.156 � 10.7 (Bq. m−3), 2.803(ppm) � 0.48,
16.34 � 4.49(Bq.kg−1), 0.00646((mWL)) � 0:00011, 0.2662 (WLMY−1)
±0:0517, 1.506 (mSv.y−1)±0:279, and 27.116 (per 106person)±5:043,
respectively. Alpha indexes were estimated for all surveyed alleys, in
addition to the radioactivity tests and the risk indices. Their values
varied between 0.053 and 0.107, with an average 0.081 � 0.0021.
Such levels are significantly smaller than the total dose given by the
United Nations Scientific Committee on the effects of atomic radiation,
especially at Exposure to 222Rn progeny (Ep) which is within the
range of 0.2–10 mSv.y−1 (UNSCEAR). Appropriate correlations
between radon concentration with uranium and radium concentration
(R2 = 0.8739 and 0.896) have been identified, respectively. The
results revealed that the amount of background radioactivity of the
alleys of old Mosul area would be within acceptable limits.
materials on the attenuation of gamma rays by FindLinear andMass
Attenuation Coefficients and examination of homogeneity for this
materialsby using spectroscopy gamma rays( UCS20)
associated with
the
(NaI (TI)) at energies of gamma rays (81, 356, 662, 1173, 1332) keV
which emitted from Sources(
133Ba,
137Cs,
60Co) respectively,were
examined homogeneity of materials using a narrow beam mono-energy
gamma rays emitted from the source of radioactive
137
Cs (662) keV
through a percentage of the difference between the intensity of gamma
rays transmission andLinearAttenuation Coefficient in four different
locations ofThe material and the percentage of standard deviation,The
more material was homogeneous shield was their best on the presence of
gaps attenuation through the material leads to increase abilityof
radiationof penetration Material,The program used (MATLAB) (version
7.1) in this study for the linear and mass attenuation coefficients curves,
which showed that the linear and mass attenuation coefficients less with
increaseenergy and also find curves homogeneity test,Thesestudy include
different types of building materials because of its importance in the
technological and industrial processes.The results showed that among
building materials the possessed Granite usedhigher the linearand mass
attenuation coefficientTherefore it can be used as a protective shield
against radiation,whileAppears Thermstone the less linear attenuation
coefficient because of its low-lying density and low concentrations of
elements with atomic number of large and this confirms the reliability of
the intensity attenuation coefficients under study and shields on the
atomic number of its Compounds, andappear Thermstone less
homogeneousbecause of The presence of air bubbles punctuated,so
Thermstone does not favor in shielding against gamma rays
governorate through measuring radioactivity concentration of radionuclide's in soil
samples collected from these regions ,and calculation of some radiological
parameters. Gamma ray spectrometers with NaI(Tl) detector system and high
purity germanium (HPGe) detector system was used for this purpose. A
comparison between obtained results for both systems showed that for the
average concentrations of radionuclide's ( 238U, 232Th, 40K , 226Ra and 214Pb)
obtained from NaI(Tl) system of these samples was found to be 41.24,21.46,
326.74, 33.55 and 11.76Bq/kg respectively, while it was found that the average
concentrations of the same natural radionuclide's obtained from HPGe system
(except for uranium 238U which was not obtained from this system) as wells as
for the artificial 137Cs radionuclide(232Th, 40K , 226Ra and 214Pb, 137Cs) was found to
be 20.30, 378.93, 32.52, 14.78 and 8.17Bq/kg respectively. In order to estimate the
radiological hazards to the humans , some of the radiological parameters were
calculated ,in which it was found that the average of absorbed dose rate D(nGy/h)
is equal to 42.12nGy/h according to NaI(Tl) system,while it was found that it is
equal to 43.08nGy/h according to HPGe system ,also annual effective dose
equivalent (outdoor) AEDE(Sv/y) was found to be 51.66Sv/y and 52.74Sv/y
for NaI(Tl) system and HPGe system respectively, however it was found the same
parameter (indoor) is equal to 206.65Sv/y and 211.37Sv/y for the two systems
respectively .The average of : radium equivalent Raeq (Bq/kg),gamma index (I)
and alpha index (I) was calculated and was found to be 89.41Bq/kg , 90.75Bq/kg
and 0.656, 0.656 and 0.167,0.162 for the two systems respectively. The
calculation of internal hazard index (Hin) and external hazard index (Hex) was
found to be 0.329,0.332 and 0.241,0.244 for the two systems respectively. Also the
averages of excess lifetime cancer risk (ELCR) and annual gonadal dose equivalent
AGDE(mSv/y) was found to be 180.8210-6, 184.5910-6 and 0.296 mSv/y,0.304
mSv/y for the two systems respectively. Finally it was found that the average
exposure dose rate I(R/h) calculated by NaI(Tl) system, was found to be 202.58
R/h.
All other samples failed to do so. These samples when connected to conventional nuclear spectroscopy electronics, gave reasonable but not high quality signals due to irradiating with 137Cs, 241Am and (137Cs+ 241Am). Matlab-software based on numerical methods were used to analyze the data. Resolution through (Full Width at Half Maximum), area under the peak and error for this detector were presented. The mobility lifetime product of both electrons and holes for CdMnTe plotted against various gamma energy sources, and then compared with respect to CdZnTe; So there was a clear increase for CdMnTe than CdZnTe.Calculations of transit time, for electrons and holes in CdMnTe, plotted against (1/V) which gave a decrease of the transit time with voltage increase. The quality factor value has been calculated for CdMnTe detector and compared to those of CdZnTe and CdTe detectors only at room temperature. The value of quality factor for CdMnTe detector was higher than the others. Calculations of activation energies of annealed CdMnTe samples for 2 and 5 hours under vacuum (10-5torr) gave 0.361 and 0.270 eV respectively.