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Natural radioactivity has been a part of the environment since the creation of earth. Natural elements like uranium and its by-products can be reason of health problems if they are present in groundwater at excessive amount. Uranium is very harmful because it is very toxic. This study gives the information about the uranium concentration in 40 groundwater samples collected from different water sources like hand pump and tube wells of different depths from numerous locations of Jhajjar district of Haryana, India. Uranium concentration was measured using the LED fluorimetry technique. The observed value of uranium concentration ranged from 5 μgL-1 to 91 μgL-1 with mean value of 28.49 μgL-1. The mean value of uranium concentration is below the safe limit suggested by World Health Organisation (WHO) and Atomic Energy Regulatory Board (AERB), India. The uranium concentration in some region is high because of nearby industries, increasing uses of fertilizer for agriculture and the local subsurface geology of the region. The calculated risk factors for lifelong cancer morbidity and mortality are not significant because they are much lower than the permitted hazard limits. The chemical toxicity of uranium is measured in form of LADD (Lifetime Average Daily Dose) value was ranging from 0.39 to 6.67 μg kg-1 day-1 with mean value of 2.02 μg kg-1 day-1g which is more than the WHO recommended daily consumption threshold of LADD of 1.0 μg kg-1 day-1. Values of annual effective dose is varying from 0.89-15.16 μSv/Y with mean value is 4.74 μSv/Y, which is below the safe limit of 100 μSv/y (WHO). [ABSTRACT FROM AUTHOR]

Copyright of Uranium Geology is the property of Uranium Geology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Uranium is characteristic lithospheric component and is found nearly in all kinds of soils and waters; in any case, its quantity changes from water-to-water contingent on their cause. Subsequently, in the current investigation, the concentration of uranium in groundwater tests was estimated utilizing LED fluorimeter and the related health hazards appraisal was checked. The concentration of uranium ranges from 0.5 to 10.7 μg L−1 with average value of 2.76 μg L−1. The excess cancer hazard was seen in the scope of 1.416×10−6 – 30.309×10−6 with an average of 7.804 ×10−6. This mean estimation of the excess cancer risk in the Kanchipuram locale is less than the greatest adequate degree of l.67 × 10−4 as per AERB (2004). Consequently, there is no hurtful impact to the neighbourhood individuals who are devouring the water in the examination zone. The average cancer mortality and grimness chances were determined to show that the probability of cancer-causing chances related to water test and significant health was evaluated utilizing hazard quotient from chemical harmfulness of uranium. The values watched for hazard quotient in all areas in the examination are beneath the edge estimation of 1, as recommended by USEPA. This shows that there are no unsafe impacts on the nearby individuals in the investigation zone. [ABSTRACT FROM AUTHOR]

Copyright of Uranium Mining & Metallurgy is the property of Uranium Mining & Metallurgy Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article presents the isotopic profiling of natural uranium mined from northern Nigeria for nuclear forensic application.

Four mined samples of natural uranium from northern Nigeria were studied through inductively coupled plasma mass spectrometry, at the Environmental Analytical Chemistry Laboratory, University of the Witwatersrand, Johannesburg. The samples were characterised for lead, thorium and uranium isotopic concentrations, isotopic ratios and age. The objective was to obtain nuclear forensic fingerprints as baseline data to add to the Nigerian National Nuclear Forensic Library. Results showed significant variation in the isotopic concentrations of lead, thorium and uranium across the mines. Isotopic ratios of 238U/235U, 235U/238U and 234U/238U across the sample of 137.881±0.007, 7.253×10-03±2.05×10-04 and 5.540×10-05±4.08×10-07 were found to be consistent with the natural values. The age of natural uranium is comparable to the age of earth. Uranium, lead, and thorium isotopic concentrations and ratios, as well as the age of the samples characterised, provide an isotopic profile that can be used for nuclear forensic application. Significance: • Given the abundant deposits of natural uranium in Africa and the consequent potential for nuclear insecurity, determining the isotopic profiles and signatures of natural uranium is important for application in nuclear forensics. • Isotopic concentrations of 232Th, 238U, 235U and 234U from the respective sampling sites differed significantly, thereby providing characteristic isotopic profiles.

This paper presents the results of sound velocity measurements performed in natural uranium during the high-rate strain of sound in - and -phase regions, as well as in a melting region at a shock wave front. The processes are recorded using the manganin sensor method (range 20–110 GPa) and the optical analyzer technique (range 70–260 GPa). In the region of the solid uranium phase, changes in Poisson's ratio, Young's modulus, bulk modulus, and shear modulus along the uranium Hugoniot are determined. [ABSTRACT FROM AUTHOR]

Summary: Natural uranium is utilized in a small percentage by the Light Water Reactor (LWR) and also by the once‐through Fast Breeder Reactor. One of the reactor designs that can increase the natural uranium utilization is the MCANDLE (Modified Constant Axial shape of Neutron flux, nuclides densities, and power shape During Life of Energy production) reactor. The scheme divides the core into several discrete regions. The modified CANDLE reactor will only need natural uranium as fuel input after reaching quasi‐equilibrium conditions. In this study, We used a core with certain Plutonium (Pu) composition in each region as a startup core. Initially, the Pu content in each region imitates that of the reactor core at the quasi‐equilibrium state. We calculated the neutronics of the initial core by the SRAC that stands for Standard Reactor Analysis Code System and used JENDL 4.0 as a nuclear data library. Plutonium (Pu) from LWR spent fuel was utilized as the initial reactor fuel. However, excess reactivity is more than 10%. It is because there are no other fission products. Therefore, we replace other fission products with a reduction in the volume of fuel cells. The volume reduction was adjusted to the level of burnup in each region at the quasi‐equilibrium condition. Hence, there are differences in the volume reduction ratio for each fuel cell. The method can reduce excess reactivity to 5%. The reduction of the volume of fuel cells can also reduce the amount of plutonium as the initial fuel for the reactor core. Also, the spent fuel burnup is 48% FIMA. The design could increase the utilization of natural uranium without an enrichment process. [ABSTRACT FROM AUTHOR]

This paper highlights an experimental model proposed for the management of nuclear materials containing natural uranium and thorium salts, based on technical and legislative methods. The investigated nuclear materials originate from laboratory chemicals with expired validity, having as manufacturers companies specialized in the manufacture of laboratory substances such as: Merck, Chemapol, Sigma Aldrich, Bucharest Reagent. The experimental program refers to several issues of great importance in the waste and environmental management, such as: a) the processing of radioactive substances containing nuclear materials and radioactive waste represented by solid objects contaminated with radionuclides from the radioactive series of U-238 and Th-232; b) gamma dose rate measurement during handling and processing of open sources of ionized radiation; c) measurement of suspicious contamination of the operating personnel which handles the equipment, including the materials used in the processing of open sources of ionizing radiation; and d) the inventory of nuclear materials according to the chemical formula, the mass of chemical substance, the mass of the nuclear element in each container and type of packaging. For the good development of processing these open sources of ionizing radiation containing nuclear materials, the ALARA principle (As Low As Reasonably Achievable) was applied, which is fundamental to the principles of radiation protection. All the measurements for determining the gamma dose rate and suspicious contamination were performed with the aid of a CoMo 170 radiometric device produced by Nuvia Instruments Gmbh Germany, equipped with a 170x100 mm2 PL detector with zinc sulfide calibrated with the aid of C-14, Co-60, Cs-137, U-238 and Am-241 radioactive isotopes and an external probe containing a scintillating crystal with sodium iodide enriched with thallium calibrated with Cs-137. [ABSTRACT FROM AUTHOR]

In this study, the long-term mobility of natural uranium in the KAERI Underground Research Tunnel (KURT) site was investigated using sequential chemical extraction and isotopic analyses of natural uranium in granite. It was found that uranium(VI) would be leached out due to preferential leaching of 234U relative 238U and concentrated by an uraniferous enrichment process through long-term interactions with the oxic KURT groundwater. Our results also suggest that the migration of the preferentially released uranium(VI) through fractured granite can be significantly retarded by secondary mineral phases formed by the weathering processes of granite. [ABSTRACT FROM AUTHOR]