High-sensitive colour indicator of absorbed dose of epithermal neutrons radiation

In our study, the high-sensitivity colour indicator of the absorbed dose of radiation of epithermal neutrons with energy 0 to 10 keV for dosimetry of low-energy neutrons was developed. We had been developed an indicator on the basis of the dye solution of arsenazo III and gadopentetic acid, allowing precisely define of absorbed dose in the range 2 to 103 Gy. The properties of arsenazo III as metallic indicator, which changes colour after binding of free ions of metals, were used. Colour of the indicator solution before irradiation and after it is stable enough in time at storage in the dark, at artificial illumination or at scattered sunlight. The developed indicator, consisting of a solution of arsenazo III and gadopentetic acid, allows estimating the absorbed dose of epithermal neutron irradiation with good accuracy and reduces the error of measurement related to changing colour of dye under the influence of other factors (light, temperature etc.) Dosimeter is tissue-equivalent and possesses a high-sensitivity neutron radiation due to the content of gadolinium in solution, which has great neutron capture cross-section. The developed dosimeter persists spectrophotometric characteristics after irradiaion within few weeks that allows to use it for measurement of the absorbed dose, both in real time mode and with the delayed measurement within few weeks.

Adsorptive removal of PAR and Arsenazo-III from radioactive waste solutions by modified sugarcane bagasse as eco-friendly sorbent

In this paper, sugarcane bagasse (SCB) was modified using phosphoric acid. The modified sugarcane bagasse (MSCB) has been used to remove 4-(2-pyridylazo)resorcinol (PAR) and Arsenazo-III (Ar-III) from liquid radioactive waste. The surface morphology and functional groups of the MSCB were studied using scanning electron microscopy (SEM), X-ray diffraction (XRD), fourier transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA). Adsorption ability of MSCB has been tested by batch mode through some relevant factors like initial pH, reaction time, initial coloring reagents (PAR and Ar-III) concentrations, and adsorbent weight. At adsorption equilibrium time 180 min and pH values of 3 and 1 for PAR and Ar-III; the maximum removal (%) for both PAR and Ar-III were 93 and 57%, respectively. The adsorption isotherm data are representative well to Freundlich isotherm model. The mean free energy of adsorption, E (kJ/mol), has been estimated as 5.75 and 2.28 kJ/mol for PAR and Ar-III, respectively, which suggests that the adsorption occurred physically. The maximum adsorption capacity of MSCB for PAR and Ar-III is 96.62 and 15.18 mg/g, respectively. The adsorption kinetics are better fitted by the pseudo-second-order model. The partial film along with intra-particle diffusion controlled the diffusion of coloring reagents from the solution bulk to the particle interior pores. Application of MSCB for removing PAR and Ar-III from simulated liquid radioactive waste containing U(VI) and Th(VI) ions has been achieved successfully.

The impact of the analytical performance specifications of calcium and albumin on adjusted calcium

Aim The generation of accurate, comparable results from traceable measurement procedures is a primary goal in harmonization efforts. In this study, the analytical performance of routine methods for calcium and albumin measurement is assessed to define the impact of the analytical bias of calcium and albumin on adjusted calcium equation performance and on reference intervals. Method In collaboration with the Wales External Quality Assurance Scheme, six months’ worth of anonymized data that cover a concentration range of clinical interest were collected. The data were grouped by analytical platforms/methods. Results Albumin BCG methods are positively biased (8%) to BCP methods. The overall bias for BCP methods ranges from 5.1 to –4.3% and the overall bias for BCG methods is from 2 to –6.7%. Bias for both methods is higher than the allowable minimal bias for albumin. Calcium concentrations for Roche Cobas CPC and NM-BAPTA, Beckman Arsenazo III, Abbott Architect Arsenazo III were within bias of 1.5 to –1%. However, Siemens calcium methods CPC and Arsenazo III appear to suffer from concentration-dependent bias ranging from +3 to –6%, which exceeds even the minimal allowable limits for calcium (1.3%). Adjusted calcium shows significant bias of 11%. Even with the exclusion of Siemens Advia, the scatter of adjusted calcium results exceeds that for total calcium. Conclusion This study shows wider than acceptable analytical variation for albumin and calcium. This variation may contribute to overall adjusted calcium equations variation and invalidate the application of a harmonized reference interval for calcium and albumin.

Radiochemical Assessment of Uranium in Locally Used Marbles

A sensitive method is used for the extraction and determination of soluble uranium in locally used marble has been developed. Isobutyl Methyl Ketone (IBMK) was used as extractant and 0.02 % (w/v) Arsenazo (III) as a chromogenic reagent. The present study assesses the gross radioactivity and extractable uranium in marble samples. A Multichannel Analyzer (MCA) coupled with NaI (Tl) crystal detector was used for the measurement of gross radioactivity whereas spectrophotometer was used to estimate the uranium contained in sample with the help of Arsenazo (III). The extraction involved the adjustment of pH at 0.9. The efficient extraction was achieved by the addition of at least 10 g of Al (NO3)3. This method involved the reduction of UO2 (+2) to U (IV) by using granulated Zinc in concentrated hydrochloric acid. The physical measurements showed the presence of gross radioactivity in the range 266.19 Bq/kg to 644.268 Bq/Kg while the chemical analysis showed the uranium concentration in the range of 0.02ppm to 0.06 ppm.