Measurement of total angular momentum values of high-lying even-parity atomic states of samarium by spectrally resolved laser-induced fluorescence technique

Spectrally resolved laser-induced fluorescence technique was used to uniquely assign total angular momentum (J) values to high-lying even-parity energy levels of atomic samarium. Unique J value assignment was done for seven energy levels in the energy region 34,800–36,200 cm⁻¹, recently observed and reported in the literature.     

Separation of uranium from iron in ground water samples using ion exchange resins

Uranium determination in environmental samples is faced with problems due to presence of iron and other major elements. Iron is also used many a times for pre-concentration of uranium and actinides. Separation of milligram quantity of Fe from microgram quantity of uranium becomes essential during the estimation step. A simple two step procedure has been standardized for separating uranium and iron using anion exchange in 0.025 M H₂SO₄. Quantitative recovery of uranium was obtained as well as good separation from iron. This method was applied for estimation of uranium in water samples.     

Estimation of submarine groundwater discharge using radium mass-balance in Mumbai Harbour Bay,Mumbai, India

Journal of Radioanalytical and Nuclear Chemistry - The Mumbai Harbour Bay (MHB), Mumbai, India houses a large number of ports, industrial units and urban settlements thus the groundwater may be...     

Two-color photoionization spectroscopy of uranium in a U–Ne hollow cathode discharge tube

A U–Ne hollow cathode discharge tube is used as a source of uranium atomic vapors as well as a photoelectron/photoion detector for carrying out two-color three-photon photoionization spectroscopy of uranium. Using the uranium excitation transition 0 cm⁻¹ (⁵L ₆ ⁰ ) → 16 900.38 cm⁻¹ (⁷M₇) at 591.5-nm laser wavelength as a first step transition and scanning the wavelength of a second laser from 558 to 568 nm, high-lying odd-parity atomic levels of uranium are studied in the energy region 34 500–34 813 cm⁻¹. All the expected 21 odd-parity atomic levels identified by various researchers in this region are observed in a single spectrum, demonstrating the high sensitivity achieved therein. In addition to this, we have identified eight autoionization resonances of uranium starting from its odd-parity atomic level at 33 801.06 cm⁻¹ pumped by two-photon excitation. Four out of these eight autoionization resonances are observed for the first time.     

Determination of Traces of Uranium and Thorium in Environmental Matrices by Neutron Activation Analysis

Radioactive elements like ²³²Th and ²³⁸U along with their daughter products, form part of all environmental matrices and are getting transferred to living beings by different pathways, leading to a continuous radiation exposure and need to be monitored. This paper presents an analytical methodology, highlighting the need to separate interfering beta- and gamma-emitters from the analytes, when neutron activation analysis is employed for the determination of traces of uranium and thorium in soil and plant materials. The method has been applied to the soil and plant materials from selected regions of India, along with standard reference materials to verify the validity of the proposed separation scheme. The overall reproducibility of the procedure was 2–10%. The concentration values of uranium and thorium so obtained, have been used to calculate transfer factors from soil to various parts of wheat plant.     

Screening levels for assessing 137Cs contamination along the coast of India

Journal of Radioanalytical and Nuclear Chemistry - Assessment of potential impacts on the environment around the nuclear facilities requires precise estimation of prevailing background...     

Development of rapid solvent extraction based radioanalytical technique for estimation of 90Sr in the presence of natural and anthropogenic radionuclides

A radiochemical technique for estimation of ⁹⁰Sr concentration by direct extraction of ⁹⁰Y with bis (2-ethylhexyl) phosphate (HDEHP) in toluene was developed and standardized. About 90% ⁹⁰Sr retained in the aqueous phase at the optimized pH 4–4.5. Cerenkov counting with 0.04 g mL⁻¹ sodium salicylate as a wavelength shifter resulted in 7.5 fold increase its Cerenkov counting efficiency. The method was validated by estimating ⁹⁰Sr in certified reference materials like, IAEA TEL 2016-03 drinking water, Spruce needle and IAEA-156 Clover. The interference of naturally occurring Ra and its β progeny especially Pb was eliminated by means of Cerenkov counting. Conventional radiochemical separation was used to compare ⁹⁰Sr activity in effluent samples.

     

Studies on matrix interferences during uranium analysis by extractive liquid scintillation technique

Journal of Radioanalytical and Nuclear Chemistry - The efficiency of ethylenediaminetetraacetic acid (EDTA) and diethylenetriaminepentaacetic acid (DTPA) in reducing the influence of salinity and...     

A review on distribution coefficient (Kd) of some selected radionuclides in soil/sediment over the last three decades

This review paper presents the different methods to estimate K_d and subsequent compiles of the K_d data on U, Ra, Th, ¹³⁷Cs and ⁶⁰Co in soil/sediment under various aquatic medium based on the extensive literature survey over the last 3-decades (1990–2019). The estimated K_d values show a very wide range and make more difficult to derive generic value. The finding suggests that K_d values are to be estimated for site-specific conditions while assessing the radionuclide transport modeling and risk analysis around the nuclear facilities. Review includes research papers, reports, reviewed papers, dissertations, published compilations and other technical documents.