Determination Of Uranium Research Articles

Determination of uranium in water samples by energy-dispersive X-ray fluorescence spectrometry after solid-phase extraction

Determination of uranium in water samples by energy-dispersive X-ray fluorescence spectrometry after solid-phase extraction

Dual-Enhancement Electrochemiluminescence Device for Ultratrace Uranium Visualized Monitoring in Fish, Hair, and Nail Samples.

Uranium is a nuclear fuel but also a hazardous contaminant due to its radioactivity and chemical toxicity. To prevent and mitigate its potential threat, the accurate monitoring of ultratrace uranium (orders of magnitude of pg g-1) in practical environmental samples has become an important scientific problem. To meet this challenge, we developed an efficient electrochemiluminescence (ECL) UO22+ detection device by a novel dual-enhancement mechanism. In detail, poly[(9,9-dioctylfuor-enyl-2,7-diyl)-alt-co-(1,4-benzo-{2,1,3}-thiadiazole)] polymer dots (Pdots) are modified by the UO22+ DNA aptamer, and rhodamine B (RhB) is combined with dsDNA to quench the ECL signal via a resonance energy transfer (RET) process. UO22+ can cut off the DNA aptamer to release RhB, which generates an ECL enhancement process, and then, UO22+ continuously combines with the DNA chain, inducing another ECL enhancement by the RET process from UO22+ to Pdots. This device achieves an ultralow detection limit (12 pg L-1) and a wide linear range (113 pg L-1-11.3 mg L-1), which can successfully give accurate determination results to the ultratrace uranium in biosamples (<1 pg g-1) to monitor the uranium simulation of fish. This work presents an efficient strategy for ultratrace uranium determination in the environment, highlighting its significance in public health and environmental fields.

Determination of uranium and thorium isotopes in NORM materials in the ceramic industry by using alpha-particle spectrometry

Determination of uranium and thorium isotopes in NORM materials in the ceramic industry by using alpha-particle spectrometry

Orthogonal signal correction assisted multivariate regression approach for the estimation of uranium and acidity in PUREX process streams

A direct UV–Visible absorbance spectrophotometric method was developed for the simultaneous determination of uranium and nitric acid concentration in the PUREX process samples. The simulated system consisted of uranium and nitric acid in concentration range corresponding to reprocessing of spent nuclear fuel discharged from nuclear reactor was prepared. The absorbance of these samples was measured in the range of 400–470 nm at a scan speed of 100 nm/s and resultant spectra were recorded. The changes in wavelength maxima of U(VI) absorption spectrum at different nitric acid concentration was utilized to determine the concentration of uranium and nitric acid in the sample by orthogonal signal correction assisted principal component regression. After the principle component regression the RMSEP for test data (Uranium: 3–21 g/L and acidity: 2–12 M) were 0.7 g/L and 0.4 M respectively. This method is superior to conventional method being followed for routine analysis of plant control samples in view of minimizing the generation of radioactive analytical waste consisting other corrosive reagents and reducing radiation exposure to operators during analysis. This method is amenable for online monitoring also.

Determination of Rare Earth Elements, Zirconium, Hafnium, Thorium and Uranium in Ultramafic Rocks by ICP‐MS after RE‐UTEVA Resin Columns for Separation and Pre‐Concentration

A simple method was developed for the determination of REEs, Zr, Hf, Th and U in ultramafic rocks by inductively coupled plasma‐mass spectrometry with a combination of RE and UTEVA extraction resins for their separation and pre‐concentration. Ultramafic rocks were digested with HNO3‐HF‐HClO4 and finally turned into 11 mol l−1 HCl solutions together with H3BO3 to remove insoluble fluorides. The removal of matrix elements was achieved during the loading procedure. Following this, REEs on RE resin, and Zr, Hf, Th and U on UTEVA resin were eluted with 10 ml of 0.24 mol l−1 HCl, with recoveries better than 94.4%. This method was validated using reference materials JP‐1, DTS‐2B, OKUM, UB‐N, MUH‐1 and DZΣ‐2, and the measurement results for target analytes were comparable to literature values, indicating its applicability to the determination of REEs, Zr, Hf, Th and U at ultra‐trace level in ultramafic rocks.

Novel biocompatible N-rich AIE fluorescent probe for live cell imaging and visual onsite detection of uranium.

A sensitive and biocompatible N-rich probe for rapid visualuranium detectionwas constructed by grafting two trianiline groups to 2,6-bis(aminomethyl)pyridine. Possessing excellent aggregation-induced emission (AIE) property and the advantages to form multidentate chelate with U selectively, the probe has been applied successfully to visualize uranium in complex environmental water samples and living cells, demonstrating outstanding anti-interference ability against large equivalent of different ions over a wide effective pH range. A large linear range (1.0 × 10-7-9.0 × 10-7mol/L) and low detection limit (72.6nmol/L, 17.28ppb) were achieved for the visual determination of uranium. The recognition mechanism, photophysical properties, analytical performance and cytotoxicity were systematically investigated, demonstrating highpotential for fast risk assessment of uranium pollution in field and in vivo.

Analysis of Thorium (Th) and Uranium (U) in radioactive wastewater sample in accordance with American Public Health Association (APHA) 3125 method

The main issue with thorium (Th) and uranium (U) in radioactive wastewater is the potential of these elements to contaminate the water bodies. The unregulated radioactive wastewater release can affect the ecosystem and potentially harm aquatic life. Therefore, there is a need to establish the analysis of Th and U using standard method to obtain better sensitivity and good confidence in the final report. In this study, the determination of uranium and thorium was employed using the American Public Health Association (APHA) method 3125 standard method. The method performance and method detection level (MDL) samples for APHA 3125 were prepared in the deionized water and digested using hot block (APHA 3030E) and microwave digester (APHA 3030K). The quantification of 238U, 235U and 232Th in the method performance and MDL samples was performed using Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). From the results, the method performance samples for both digestion methods were in accordance with the APHA requirement. The MDL obtained from APHA 3030E for 232Th, 238U, and 235U were 5, 7, and 8 μg L−1 respectively. Meanwhile, the MDL obtained from the microwave digester for 232Th, 238U, and 235U, and were 2, 3, and 3 μg L−1 respectively. The APHA 3030K digestion technique gives lower and better detection limit compared to the APHA 3030E technique. Based on APHA 3030K MDL, 232Th was detected in the radioactive wastewater sample while 238U and 235U were less than MDL. Meanwhile, for APHA 3030E, all elements were below MDL. This study will enhance the detection of uranium and thorium in the radioactive wastewater sample towards better environmental monitoring programs at the national and global levels.

A New Spectrophotometric Method for the Determination of Uranium (VI) and Thorium (IV) in Diversified Rocks Using the Chromogenic Calcon Dye

A New Spectrophotometric Method for the Determination of Uranium (VI) and Thorium (IV) in Diversified Rocks Using the Chromogenic Calcon Dye

The transfer of irradiated uranium from the Irish Sea coast to the terrestrial environment in Cumbria, UK

Abstract Sea-to-land transfer of irradiated uranium in soil samples was measured along a transect from the Cumbrian coast south of the Windscale Sellafield nuclear site in a NE direction across the Cumbrian coastal plain. Soluble uranium components were extracted by ion exchange chromatography and ratios 236U:238U and 235U:238U were measured using multi-collector ICP-MS. The method employed demonstrated the utility of 236U ratio measurements for the determination of irradiated uranium in environmental samples. The results produced for uranium were like those that have been reported for other fission product and nuclear fuel components that have been shown to be marine in origin. Measured 236U levels were highest close to the seashore and decreased rapidly as an exponential function of distance. The results indicated the absence of depleted uranium, such as might result from the deposition of aerosols generated by the testing of DU munitions at the nearby Eskmeals firing range in all but one sample.

Reverse phase liquid chromatographic method for the measurement of uranium in process stream solutions from uranium extraction facility

Abstract The present paper describes a simple method for the determination of uranium in uranium process stream solutions by reversed-phase liquid chromatographic method using C18 column, mixture of α-hydroxy isobutyric acid and methanol as eluent and flow-through spectrophotometer detector. This method has an advantage that interfering elements like rare-earth elements do not retain on the column and elute near the solvent peak thereby not interfering with uranium elution peak. Different eluents and parameters like pH, concentration of eluent are studied for the purpose. The spiking standard recovery was found to be more than 90 %. The developed method has been compared with other techniques and found to be in agreement.

Rapid Determination Of Uranium In Ore Samples By Online Extraction Coupled ICP-MS

Rapid Determination Of Uranium In Ore Samples By Online Extraction Coupled ICP-MS

Extended total number density compensation for uranium determination by laser-induced breakdown spectroscopy

BackgroundVariations in plasma properties among spectra and samples lead to significant signal uncertainty and matrix effects in laser-induced breakdown spectroscopy (LIBS). To address this issue, direct compensation for plasma property variations is considered highly desirable. However, reliably compensating for the total number density variation is challenging due to inaccurate spectroscopic parameters. For reliable compensation, a total number density compensation (TNDC) method was presented in our recent work, but its applicability is limited to simple samples because of its strict assumptions. In this study, we propose a new pre-processing method, namely extended TNDC (ETNDC), to reduce signal uncertainty and matrix effects in the more complex analytical task of uranium determination. ResultsETNDC reflects the total number density variation with a weighted combination of spectral lines from all major elements and incorporates temperature and electron density compensation into the weighting coefficients. The method is evaluated on yellow cake samples and combined with regression models for uranium determination. Using the typical validation set and line combination, the mean relative standard deviation (RSD) of U II 417.159 nm in validation samples decreases from 4.92% to 2.27%, and the root mean square error of prediction (RMSEP) and the mean RSD of prediction results decrease from 4.81% to 1.93% and from 1.92% to 1.56%, respectively. Furthermore, the results of 10 validation sets and 216 line combinations show that ETNDC outperforms baseline methods in terms of average performance and robustness. SignificanceFor the first time, ETNDC explicitly addresses the temperature and electron density variations while compensating for the total number density variation, where the inaccurate spectroscopic parameters are avoided by fitting related quantities using concentration information. The method demonstrates effective and robust improvement in signal repeatability and analytical performance in uranium determination, facilitating accurate quantification of the LIBS technique.

HR GRS-HPGe as NDT method for quantification of uranium and 235U content in process stream samples from UO2 fuel production facilities

Abstract Uranium concentration and uranium isotopic content are two important and critical parameters for any nuclear fuel fabrication facilities. In the present study emphasis has been given on the usage of high resolution gamma ray spectrometric (HR-GRS) technique with HPGe detector for the determination of uranium and 235U content in uranium process stream samples. The work has been carried out with an aim to give quick analytical feedback to production facility and also to minimize the generation of analytical waste. These are important requirements for any industrial lab with high analytical load attached to production facility. In this paper a simple and a non-destructive testing (NDT) method has been described for quantification of uranium and 235U content in samples received from UO2 fuel production facilities using HR-GRS technique with high purity germanium (HPGe) detector. A 185.7 keV line of 235U has been used for quantification of uranium in process solutions containing 1 g/L to 600 g/L of uranium covering both aqueous and organic process stream solutions. The results have been compared with that of Davies and Gray method. The limitations associated with gamma ray emitted from daughter products of 238U and self-induced or self-excited X-ray fluorescence lines of uranium have also been studied. Multi Group Analysis of Uranium (MGAU) software code has been used for measurement of 235U content in variety of samples. The results obtained are compared with that of results by thermal ionization mass spectrometer (TIMS).

A radiochemistry laboratory exercise: determination of uranium in tap water by solvent extraction and liquid scintillation counting

Environmental radiochemistry is a key pillar of the education of nuclear engineering students and young professionals. Teaching the fundamentals of this multidisciplinary field is best performed also through well-designed hands-on experiments. A simple and fast radiochemical procedure has been developed to determine uranium in tap water by liquid scintillation counting. The proposed method provides reliable and repeatable results, with accuracy and precision within 5%. It can be proficiently executed by undergraduate students, who have appreciated the engagement and got acquainted with standard analysis protocols, from sample collection and manipulation to radiometric measure and data analysis.

Permeability evolution mechanism and the optimum permeability determination of uranium leaching from low-permeability sandstone treated with low-frequency vibration

Permeability evolution mechanism and the optimum permeability determination of uranium leaching from low-permeability sandstone treated with low-frequency vibration

Determination of Uranium in Rock, Soil, and Fruits at Bodal Mines of Rajnandgaon District, Chhattisgarh, Using LED Fluorimetry

Determination of Uranium in Rock, Soil, and Fruits at Bodal Mines of Rajnandgaon District, Chhattisgarh, Using LED Fluorimetry

Recent advances in ultra‐trace determination of uranium in natural water using total reflection X‐ray fluorescence (TXRF) spectrometry

AbstractThis review article describes some of the recent advances in ultra‐trace determination of uranium in various natural water bodies such as drinking water, underground water, seawater, etc. using total reflection x‐ray florescence (TXRF) spectrometry. Uranium is one of the most hazardous element having chemical as well as radio‐toxicity. However, due to its low concentration in water samples, direct determination is seldom possible in samples with high salt content. Various sample preconcentration and selective extraction techniques for uranium such as solvent extraction, dispersive liquid–liquid micro extraction, solid phase extraction, and membrane based preconcentration methods are summarized in this article. TXRF is a very versatile micro‐analytical technique with detection limits in picogram range and having multielemental analysis capability. TXRF determination of uranium using U Lα as the analytical line has many analytical challenges and difficulties, mainly due to the severe interference with Rb and Br, both are commonly available in natural water samples. This article highlights some of these challenges, along with the advantages and disadvantages of the different sample preparation techniques used so far for uranium determination in natural water samples by TXRF.

Quantitative Determination of Uranium with UV-Visible Spectroscopy in Nitrated Media at High Concentration

Quantitative Determination of Uranium with UV-Visible Spectroscopy in Nitrated Media at High Concentration

Synthesis and Application of a New Polymer with Imprinted Ions for the Preconcentration of Uranium in Natural Water Samples and Determination by Digital Imaging.

This work proposes the synthesis of a new polymer with imprinted ions (IIP) for the pre-concentration of uranium in natural waters using digital imaging as a detection technique. The polymer was synthesized using 2-(5-bromo-2-pyridylazo)-5-diethylaminophenol (Br-PADAP) for complex formation, ethylene glycol dimethacrylate (EGDMA) as a crosslinking reagent, methacrylic acid (AMA) as functional monomer, and 2,2'-azobisisobutyronitrile as a radical initiator. The IIP was characterized by Fourier transform infrared spectroscopy and scanning electron microscopy (FTIR). Uranium determination was performed using digital imaging (ID), and some experimental conditions (sample pH, eluent concentration, and sampling flow rate) were optimized using a two-level full factorial design and Doelhert response surface methodology. Thus, using the optimized conditions, the system allowed the determination of uranium with detection and quantification limits of 2.55 and 8.51 µg L-1, respectively, and a pre-concentration factor of 8.2. All parameters were determined using a 25 mL sample volume. The precision expressed as relative deviation (RSD%) was 3.5% for a solution with a concentration of 50 µg L-1. Given this, the proposed method was used for the determination of uranium in four samples of natural waters collected in the city of Caetité, Bahia, Brazil. The concentrations obtained ranged from 35 to 75.4 μg L-1. The accuracy was evaluated by the addition/recovery test, and the values found ranged between 91 and 109%.

Application of Poly(caffeic acid) for the Extraction of Critical Rare Earth Elements.

Poly(caffeic acid) was synthesized and utilized for the extraction and determination of rare earth elements (REEs), thorium, and uranium. Oxidative polymerization of caffeic acid, a low-cost plant-based material, in the presence of ethylenediamine produced a granular, air-stable, and cross-linked polymer. The polymer is highly oxygenated and together with the amino group from ethylenediamine efficiently coordinates and preconcentrates these critical elements from aqueous media. Extraction was dependent on solution pH, amount of sorbent, and extraction time, while the concentration and flow rate of the desorption solution governed the recovery efficiency. Removal and recovery efficiencies greater than 98 and 90%, respectively, and low levels of detection ranging from 0.1 to 2.9 ng/L were achieved. Determination of these strategic elements in the presence of potentially interfering ions as well as in complex matrices such as well water and produced water samples also was demonstrated. The capacity of poly(caffeic acid) was determined with lanthanum as a representative REE to be 161.7 mg/g, establishing the promise of poly(caffeic acid) for larger-scale extractions in addition to the ability to screen sources for the presence of REEs.