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Estimation of Terrestrial Gamma Radiation Dose and Annual Effective Dose Around Industrial Areas of Tumkur City

Estimation of Terrestrial Gamma Radiation Dose and Annual Effective Dose Around Industrial Areas of Tumkur City

This study presents the results of indoor and outdoor ambient gamma dose rates measured in and around industrial areas of Tumkur city. 15 locations from four major industrial areas around Tumkur city in Karnataka state, India have been selected for the study. These measurements were carried out by using environmental radiation Dosimeter ER-709 which is a portable detector. By the measured average absorbed dose rates, annual effective dose (AED) has been calculated by a standard method. Results showed that the indoor and outdoor absorbed dose rates in air of Tumkur industrial areas ranged between 137 to 310nGy/h with an average of 226.1nGy/h and 88 to 275 nGy/h with an average of 188.3 nGy/h respectively. The indoor and outdoor AED ranged between 0.672 to 1.521 mSv/y with an average value of 1.09 mSv/y and 0.108 to 0.337 mSv/y with an average value of 0.231 mSv/yrespectively. The total effective dose ranges from 0.780 to 1.858 with an average of 1.340 mSv/y. The calculated indoor and outdoor AEDs were found to be higher than the world average.
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Terrestrial Gamma Radiation Dose Rate of West Sarawak

Terrestrial Gamma Radiation Dose Rate of West Sarawak

Abstract. A study of terrestrial gamma radiation (TGR) dose rate was conducted in west of Sarawak, covering Kuching, Samarahan, Serian, Sri Aman, and Betong divisions to construct a baseline TGR dose rate level data of the areas. The total area covered was 20,259.2 km 2 , where in-situ

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Natural radioactivity in major rivers of Kelantan state, Malaysia

Natural radioactivity in major rivers of Kelantan state, Malaysia

[12] Garba, N. N., A. T. Ramli, M. A. Saleh, M. S. Sanusi and H. T. Gabdo. 2014. Assessment of Terrestrial Gamma Radiation Dose Rate (TGRD) of Kelantan State, Malaysia: Relationship Between the Geological Formation and Soil Type to Radiation Dose Rate. Journal of Radioanalytical and Nuclear Chemistry. 302: 201-209.

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Radioactivity levels of 238U and 232Th, the α and β activities and associated dose rates from surface soil in Ulu Tiram, Malaysia

Radioactivity levels of 238U and 232Th, the α and β activities and associated dose rates from surface soil in Ulu Tiram, Malaysia

Dystric Nitosols soil types with underlying geological formation of acid intrusive rock are the most abundant in Ulu Tiram. These geological formation and soil types contain highest concentration of primordial radionuclides especially 238 U and 232 Th. 20 This result is similar to those from other studies nearby the districts such as Kota Tinggi, 17 Pontian 16 and some other places in Johor state, Malaysia. 238 U and 232 Th are generally enriched in the youngest, most felsic and most potassic members of comagmatic suites of igneous rocks. 21 This caused the higher of gamma-radiation dose rates measurements obtained in Ulu Tiram. The mean of the terrestrial gamma-radiation dose rates obtained from the area covered by Dystric Nitosol with underlying of acid intrusive rock is 211r11 nGy.h –1 .
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Environmental radiology assessment in Lahad Datu, Sabah

Environmental radiology assessment in Lahad Datu, Sabah

Abstract. Monitoring terrestial gamma radiation is crucial to prepare a baseline data for environmental radiological protection. Radiological research was carried out in Lahad Datu, Sabah to obtain the radioactivity status and terrestrial gamma radiation level in the area. We measure the terrestrial gamma radiation dose rates and analyse the radioactivity concentration of primordial radionuclides for radiological risk assessment. We identified that the annual estimation of dose effective for public is below the public dose limit, 1 mSv per year. Public and environment safety and health are remain secure. The obtained data and results can be used as reference for environmental radiology protection.
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Natural environmental radioactivity in the soil of Terengganu State, Malaysia

Natural environmental radioactivity in the soil of Terengganu State, Malaysia

[21]. Garba, N. N., Ramli, A. T., Saleh, M. A., Sanusi, M. S. and Gabdo, H. T. Assessment of terrestrial gamma radiation dose rate (TGRD) of Kelantan State, Malaysia: Relationship between the geological formation and soil type to radiation dose rate. Journal of Radioanalytical and Nuclear Chemistry. 2014. 302(1): 201- 209.

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Terrestrial Gamma Radiation in Phuket Island, Thailand

Terrestrial Gamma Radiation in Phuket Island, Thailand

The terrestrial gamma dose rate measurements were done during February 2010. A total of 124 data points were collected along the selected route, with the distance between each survey point at about 2 km apart, covering approximately a total distance of 285 km. Figure 2 (left) shows the survey point mapped with the geology of Phuket Island. The terrestrial gamma dose rate of the island (excluding the abandoned area of the old dressing plant) obtained at 1 meter above ground ranged from 20 to 900 nGy h -1 , with the geometric mean value of 185 nGy h -1 . The distribution of terrestrial gamma dose rate data is presented as a histogram in Fig. 3. This shows that the data follow a log-normal distribution. The absorbed dose rate at the famous, Patong beach, ranged between 52 and 80 nGy h -1 which agreed with the result of 47 nGy h -1 reported earlier by D. Malaian, et al. [36]. The highest dose rate of 900 nGy h -1 was found on the surface mountain soil located on the south coast of the island. At that time of this investigation, mountain soil was being evacuated for constructing of a local road nearby. In the city area, we found a relatively high absorbed dose rate of 492 nGy h -1 on the pavement of one main road near a population center which is higher than the nearby uncovered soil about 2-3 times. We cannot be sure of the explanation for this anomaly but suspect that some of the aggregate used in making the concrete for the road surface here contained some NORM material.
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Natural radiation and radioactivity in soil and groundwater of Jos Plateau, Nigeria

Natural radiation and radioactivity in soil and groundwater of Jos Plateau, Nigeria

This study aimed to establish baseline data on the natural environmental gamma radiation and radioactivity levels as well as to evaluate the corresponding radiological health impacts for Jos plateau, Nigeria. It employed the use of portable NaI(Tl) survey meter and hyper pure germanium spectrometer to measure external gamma dose rate and to determine the specific activity concentration of terrestrial radionuclides, 226 Ra, 232 Th and 40 K in soil samples, respectively. External gamma dose rates were measured at 811 locations while activity concentration were determined for 102 soil samples. The mean value for the measured gamma dose rate was found to be approximately four times the world average value while the mean values for the activity concentration of 226 Ra, 232 Th and 40 K were found to distinctly exceed their corresponding world reference values for continental soil. Gamma dose rate and activity concentration of the terrestrial radionuclides for each geological formation and soil type of the area are presented. Statistical relationships between gamma dose rate with the different geological formations and soil types of the area are established. Younger granites geological formation and Haplic acrisols soil type were found to contribute the highest to the natural background radioactivity and
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Effects of Food Diet Preparation Techniques on Radionuclide Intake and Its Implications for Individual Ingestion Effective Dose in Abeokuta, Southwestern Nigeria

Effects of Food Diet Preparation Techniques on Radionuclide Intake and Its Implications for Individual Ingestion Effective Dose in Abeokuta, Southwestern Nigeria

Baseline studies of terrestrial outdoor gamma dose rate levels in Nigeria had shown that the areas under investi- gation exhibited high concentrations of natural radionu- clides [1,3]. Also recently an annual effective dose rate of 1.64 mSv due to environmental radiation has been reported for the city [4]. Metal pollution in shallow well water samples in the neighboring town to the study areas has been reported [5], radioactivity in borehole water in neighboring state [6] and in part of Ogun State [7]. It is therefore envisaged that radionuclide concentrations may be elevated in the different food crops and the diets de- rivable from them. For broad assessment of dose estimate, knowledge of the radiological impact on the effect of
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Gamma Dose Rate And  Effective Dose Equivalent Due To Gamma Radiation From Granite Samples Collected From Prominent Quarry Sites In Oyo State, Nigeria

Gamma Dose Rate And Effective Dose Equivalent Due To Gamma Radiation From Granite Samples Collected From Prominent Quarry Sites In Oyo State, Nigeria

The external terrestrial -radiation absorbed dose rate in air at a height of about 1m above the ground was calculated by using the conversion rate of 0.0414 nGyh -1 /Bqkg -1 for 40 K, 0.461 nGyh -1 /Bqkg -1 for 226 Ra and 0.623 nGyh -1 /Bqkg -1 for 232 Th (UNSCEAR,1993) assuming that 137 Cs, 90 Sr and the 235 U decay series can be neglected as they contribute very little to the total dose from environmental background (Kocher and Sjoreen, 1985; Jacob et al., 1986; Leung et al, 1990).

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Assessment of Natural Radioactivity Levels and Radiation Dose Rate in Some Soil Samples from Historical Area, AL RAKKAH, Saudi Arabia

Assessment of Natural Radioactivity Levels and Radiation Dose Rate in Some Soil Samples from Historical Area, AL RAKKAH, Saudi Arabia

The analysis focuses on measuring 226 Ra, 232 Th, and 40 K activities in the soil samples. Due to the difficulty of determination the activity of 226 Ra and 232 Th directly from their very weak energy’s lines, the concentrations for both of them are determined from their decay products assuming secular equilibrium between parents and daughters. The peak analysis was conducted for the most significant energy lines for each radioisotope. The de- termination of activity concentration of 226 Ra was by using the most abundant gamma rays from the lead 214 Pb at 295 keV (18.15%) yield and at 352 keV (35.10%) yield, and from 214 Bi being at 1764 keV (15.1%) yield, where the other energy lines yields are below 5% which are too small to detect with enough confidences. The activities obtained from these three lines were averaged and the mean value was considered as the activity concentration of 226 Ra. The specific activity of 232 Th was evaluated from gamma-ray lines of 228 Ac at 338.4, 911.1 and 968.9 keV. The specific activity of 40 K was determined directly from its 1460.8 keV gamma-ray line. The activity concentrations of the natural radionuclides in the measured samples (A S ) were computed using the following
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CT versus MR Imaging in Estimating Cochlear Radiation Dose during Gamma Knife Surgery for Vestibular Schwannomas

CT versus MR Imaging in Estimating Cochlear Radiation Dose during Gamma Knife Surgery for Vestibular Schwannomas

cochlea were generated from the available CT and T2 images, and the mean and maximum doses were obtained for each patient. Additionally, the cochlear volume receiving 3- and 4.2-Gy radia- tion doses was obtained using the dose-volume histogram gen- erated by the software. After the treating neurosurgeon, radi- ation oncologist, and the medical physicist approved the treatment plan, the treatment began. The median gross tumor volume as determined by postgadolinium T1 MR imaging was 0.97 cm 3 (range, 0.02–16.5 cm 3 ). The median margin dose was

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Methodology for the nuclear design validation of an Alternate Emergency Management Centre (CAGE)

Methodology for the nuclear design validation of an Alternate Emergency Management Centre (CAGE)

Abstract. The methodology is devised by coupling different codes. The study of weather conditions as part of the data of the site will determine the relative concentrations of radionuclides in the air using ARCON96. The activity in the air is characterized depending on the source and release sequence specified in NUREG- 1465 by RADTRAD code, which provides results of the inner cloud source term contribution. Known activities, energy spectra are inferred using ORIGEN-S, which are used as input for the models of the outer cloud, filters and containment generated with MCNP5. The sum of the different contributions must meet the conditions of habitability specified by the CSN (Spanish Nuclear Regulatory Body) (TEDE <50 mSv and equivalent dose to the thyroid <500 mSv within 30 days following the accident doses) so that the dose is optimized by varying parameters such as CAGE location, flow filtering need for recirculation, thicknesses and compositions of the walls, etc. The results for the most penalizing area meet the established criteria, and therefore the CAGE building design based on the methodology presented is radiologically validated.
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Improvement of microbiological quality of hen egg powder using gamma irradiation

Improvement of microbiological quality of hen egg powder using gamma irradiation

Egg disinfection has two purposes. One is to re- duce the overall abundance of TVC and MYC that may affect egg respiration and survival. The other is to reduce or eliminate pathogens that may affect egg and fry survival, and compromise the health certification of a hatchery (Barnes, Bergmann, Stephenson, Gabel, & Cordes, 2005). Results of this study indicated that the current practices of gamma irradiation treatment achieve the first and second objectives. This is important for situations in which hatcheries receive eggs from wild sources, or from other hatcheries and processes.

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Comparison of Gamma Radiation Crosslinking and Chemical Crosslinking on Properties of Methylcellulose Hydrogel

Comparison of Gamma Radiation Crosslinking and Chemical Crosslinking on Properties of Methylcellulose Hydrogel

The untreated MC film, chemically crosslinked MC film, and radiation crosslinked film are shown in Fig. 5(a), (c), and (e), respectively. From these figures, it can be seen that the chemically crosslinked MC film at 0.5wt% of GA and the radiation crosslinked film at 25 kGy of dose of gamma ray are clear transparent films. However, the surface textures of radiation MC films were rough. This phenomenon could possibly due to the fact as follows. For chemical crosslinking process, the solvent was gradually evaporated in an air-circulated chamber at ambient temperature, thus resulting in smooth films. For radiation-induced crosslinking process, the heat generated during the irradiation may result in initial evaporation of solvent which in turn leads to the increase of the viscosity of the MC solution, making it more difficult for the remaining solvent to evaporate later in air-circulated chamber at ambient temperature, hence resulting in samples with rough surfaces.
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SOIL AND VEGETATION FROM NOVI PAZAR (SERBIA) AND ROŽAJE (MONTENEGRO): RADIOACTIVITY IMPACT ASSESSMENT

SOIL AND VEGETATION FROM NOVI PAZAR (SERBIA) AND ROŽAJE (MONTENEGRO): RADIOACTIVITY IMPACT ASSESSMENT

The samples were prepared (dried, sieved), weighed (NP – 0.5 kg each; R1 – 0.81 kg, R2 – 1.144 kg, R3 – 1.057 kg), and sealed in Marinelli beakers. Measurements were performed using the ORTEC HPGe detectors (40190, relative efficiency – 40 %; and 30185-S with relative efficiency – 35 %), calibrated using standard mixtures of gamma emitting isotopes in Marinelli beakers (Czech Metrology Institute). Radioisotope activity concentrations were determined in the standard photopeak analyses (using the total net counting rate under the selected photopeak, photoefficiency, gamma ray intensity and mass of the sample) – 137 Cs (662 keV); 226 Ra, i.e., 214 Bi (609 keV); 232 Th, i.e., 228 Ac (911 keV); 40 K (1461 keV). Measuring
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Natural radioactivity levels and radiation hazards for gypsum materials used in Egypt

Natural radioactivity levels and radiation hazards for gypsum materials used in Egypt

Finely ground gypsum rock was used in agriculture and other industries to neutralize sodic soils, to improve soil permeability, to add nutrients, to stabilize slopes, and to provide catalytic support for maximum fertilizer bene- fits. Small amounts of high-purity gypsum also were used in a wide range of industrial operations, including the production of foods, glass, paper, and pharmaceuti- cals. Amongst the activities identified in the European, Basic Safety Standards Directives (BSS), which the standard sets the concern “with the production of resi- dues which contain naturally occurring radionuclides causing a significant increase with the exposure of members from the public…”. Such materials may in- clude coal ash from power stations, by-product gypsum and certain slugs, which are produced in large volumes and, which may potentially be used as building materials [3]. Scientific investigations have long concluded that prolonged exposure to low-dose radiation can induce deleterious effects in humans; it was found necessary to establish levels of radioactivity in this product and asso- ciated radiation risk [4]. The aim of this paper is to in-
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PERSONAL RADIATION DETECTOR γ-TRACER GT2-1 WITH A CdZnTe DETECTOR

PERSONAL RADIATION DETECTOR γ-TRACER GT2-1 WITH A CdZnTe DETECTOR

The device’s search mode employs a proprietary Background Variation Tracking (BVT) algorithm. The implemented search and gamma-radiation source localization mechanisms facilitate the rapid (1–3 sec) detection of weak gamma- radiation sources with intensities that exceed the background level by a factor of 1.5–3. Analysis of the time intervals between adjacent pulses in the input sequence is used to determine numeric characteristics that are also displayed in a user-friendly graphical form. The dedicated GUI approach and sound capabilities are tailored to facilitate search activities and support the operator in gaining experience with the device.
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has promulgated the false idea that aerosol particulates cause global cooling by blocking sunlight [2,23-25]. However, it has recently become clear that aerosol particles are efficient absorbers of solar radiation, either separately as large particles or as assemblages of small particles which rapidly transfer that heat to the surrounding atmospheric gases [10,26-29]. Atmospheric heating by particulate matter has been said to cause “changes in the atmospheric temperature structure” [30] without mentioning the consequences on atmospheric convection and the concomitant surface-heat-transfer reduction that results from such changes.
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Modulation of Phosphatase Levels in Swiss Albino Mice by Genistein Treatment against Radiation-induced Effect

Modulation of Phosphatase Levels in Swiss Albino Mice by Genistein Treatment against Radiation-induced Effect

Genistein, a soya isoflavone, is found naturally in legumes, such as soybeans and chickpeas. If taken an average of intervals of month periods (1 st , 3 rd , 7 th , 15 th and 30 th days) into account, the intraperitoneal administration of optimum dose (200 mg/kg body weight) of Genistein before 24 hrs and 15 minutes of irradiation (8 Gy at a dose rate of 1.02 Gy/min) subsides the radiation induced augmentation of the acid phosphatase (by 34.7 ± 12.39% and 28.38 ± 9.41% in pre, and post irradiated groups, respectively ) and ameliorated the decline of the alkaline phosphatase (by 49.59 ± 13.82% and 45.44 ± 15.34% in pre and post irradiated groups, respectively ) while comparing the experimental group with that control group (only irradiated) in Swiss albino mice. The results indicate that Genistein against radiation effect may pave way to the formulation of medicine in radiotherapy for normal tissue. Present study also establishes the fact that Genistein may be used as a radioprotector before and after radiation exposure. Hence, the possibility of its use as radioprotectant and radiotherapeutic drug in accidental conditions or nuclear war conditions can not be ruled out.
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