Title: Journal of Environmental Radioactivity

Title: Journal of Environmental Radioactivity

ISO Abbreviated Title: J Environ. Radioactiv.

JCR Abbreviated Title: J Environ Radioactiv

ISSN: 0265-931X

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Publisher: Elsevier Sci Ltd, Oxford

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: Impact Factor

Sajo-Bohus, L., Gómez, J., Capote, T., Greaves, E.D., Herrera, O., Salazar, V. and Smith, A. (1997), Gross alpha radioactivity of drinking water in Venezuela. Journal of Environmental Radioactivity, 35 (3), 305-312.

Full Text: J\J Env Rad35, 305.pdf

Abstract: Bottled mineral water is consumed by a large population in Venezuela. The alpha emitters concentration was measured in samples of bottled water and water springs collected near the surface. Approximately 30% of the total mineral water suppliers was monitored. A database on natural and artificial radioactivity in drinking water was produced. Results indicate that 54% of the waters sampled contain a total alpha radioactivity of less than 0.185 Bq l^-1 and only 12% above 0.37 Bq l^-1. Our results revealed a total annual dose of 2.3 mSv year^-1. (C) 1997 Elsevier Science Limited.

Dumat, C. and Staunton, S. (1999), Reduced adsorption of caesium on clay minerals caused by various humic substances. Journal of Environmental Radioactivity, 46 (2), 187-200.

Full Text: J\J Env Rad46, 187.pdf

Abstract: The effect of the addition of various humic substances on the adsorption of caesium on two mineral clays has been studied. All measurements were carried out in dilute suspension under controlled conditions of temperature and ionic strength. Only a small proportion of the humic substance was adsorbed on the clays (<10%). In general, the affinity of the clay-humic complexes for caesium was less than that of the bare clay. The decrease was greater for illite than for montmorillonite, and greatest at trace concentrations of caesium and increased with increasing concentration of each humic substance. However, no correlation was found between the amount of humic substance adsorbed and the decrease in Cs adsorption when all complexes were considered. Neither size nor the origin of the humic substances could explain the extent of the adsorption decrease. Since neither steric hindrance nor decrease in the number of adsorption sites was the driving force behind this phenomenon, it is hypothesized that the affinity of the clay surface is modified by the organic macromolecules. The highly selective frayed edge sites of illite are particularly sensitive to the adsorption of polyanions because of their proximity to anion adsorption sites. The observed decrease in Cs adsorption may contribute to the unexpectedly high bioavailability of Cs in organic soils. (C) 1999 Elsevier Science Ltd. All rights reserved.

Keywords: Soil Organic-Matter, Sorption-Desorption, Acid, Cesium, Radiocesium, Fixation, Illite, Cs-137, Cation, Cs

? Ohnuki, T., Aoyagi, H., Kitatsuji, Y., Samadfam, M., Kimura, Y. and Purvis, O.W. (2004), Plutonium(VI) accumulation and reduction by lichen biomass: correlation with U(VI). Journal of Environmental Radioactivity, 77 (3), 339-353.

Full Text: 2004\J Env Rad46, 339.pdf

Abstract: The uptake of plutonium(VI) and uranium(VI) by lichen biomass was studied in the foliose lichen Parinotrema tinctorum to elucidate the migration behavior of Pu and U in the terrestrial environment. Pu and U uptake by P. tinctorum averaged 0.040 0.010 and 0.0550.015 g g(dry)^-1, respectively, after 96 h incubation with 4.010^-4 mol l^-1 Pu solutions of pH 3, 4 and 5. SEM observations showed that the accumulated Pu is evenly distributed on the upper and lower surfaces of P. tinctorum, in contrast to U(VI), which accumulated in both cortical and medullary layers. UV/VIS absorption spectroscopy demonstrates that a fraction of Pu(VI) in the solution is reduced to Pu(V) by the organic substances released from P. tinctorum, and the accumulated Pu on the surface is reduced to Pu(IV), while U(VI) keeps the oxidation state of VI. Since the solubility of Pu(IV) hydroxides is very low, reduced Pu(VI) does not penetrate to the medullary layers, but is probably precipitated as Pu(IV) hydroxides on the cortical lichen surface. It is concluded that the uptake and reduction of Pu(VI) by lichens is important to determine the mobilization and oxidation states of Pu in the terrestrial environment. (C) 2004 Elsevier Ltd. All rights reserved.

Keywords: Plutonium, Uranium, Lichen, Uptake, Reduction, Accumulation, Uranium, Biosorption, Environment, Melanins, Metals, Bioaccumulation, Speciation, Polymers, Binding, IV

? Xie, S.B., Zhang, C., Zhou, X.H., Yang, J., Zhang, X.J. and Wang, J.S. (2009), Removal of uranium(VI) from aqueous solution by adsorption of hematite. Journal of Environmental Radioactivity, 100 (2), 162-166.

Full Text: 2009\J Env Rad100, 162.pdf

Abstract: Hematite, a type of inorganic-sorptive medium, was used for the removal of U(VI) from aqueous solutions. Variables of the batch experiments including solution pH, contact time, initial concentration, temperature, calcium and magnesium ions were studied. The results indicated that the adsorption capacities are strongly affected by the solution pH, contact time and initial concentration. A higher pH favors higher U(VI) removal. The adsorption was also affected by temperature and calcium and magnesium ions, but the effect is very weak. The maximum adsorption capacity (q(m)) only increased from 3.36 mg g^-1 to 3.54 mg g^-1 when the temperature was increased from 293 K to 318 K. A two-stage kinetic behavior was observed in the adsorption of uranium(VI): very rapid initial adsorption in a few minutes, followed by a long period of slower uptake. It was found that an increase in temperature resulted in a higher uranium(VI) loading per unit weight of the sorbent. The adsorption of uranium by hematite had good efficiency, and the equilibrium time of adsorbing uranium(VI) was about 6 h. The isothermal data were fitted with both Langmuir and Freundlich equations, but the data fitted the former better than the latter. The pseudo-first-order kinetic model, pseudo-second-order kinetic model and intraparticle diffusion model were used to describe the kinetic data, but the pseudo-second-order kinetic model was the best. The thermodynamic parameter G were calculated, the negative G values of uranium(VI) at different temperatures confirmed the adsorption processes were spontaneous. (C) 2008 Elsevier Ltd. All rights reserved.

Keywords: Adsorption, Adsorption Isotherm, Complexes, Hematite, Model, Sorption, Uranium(VI) or U(VI)

? Anirudhan, T.S. and Radhakrishnan, P.G. (2009), Improved performance of a biomaterial-based cation exchanger for the adsorption of uranium(VI) from water and nuclear industry wastewater. Journal of Environmental Radioactivity, 100 (3), 250-257.

Full Text: 2009\J Env Rad100, 250.pdf

Abstract: The amine-modified polyhydroxyethylmethacrylate (poly(HEMA))-grafted biomaterial (tamarind fruit shell, TFS) carrying carboxyl functional groups at the chain end (PGTFS-COOH) was prepared and used as an adsorbent for the removal of uranium(VI) from water and nuclear industry wastewater. MR spectral analysis revealed that U(VI) ions and PGTFS-COOH formed a chelate complex. The adsorption process was relatively fast, requiring only 120 min to attain equilibrium. The adsorption kinetic data were best described by the pseudo-second-order equation. The equilibrium adsorption data were correlated with the Sips isotherm model. The maximum U(VI) ions uptake with PGTFS-COOH was estimated to be 100.79 mg/g. The complete removal of 10 mg/L U(VI) from simulated nuclear industry wastewater was achieved by 3.5 g/L PGTFS-COOH. The reusability of the adsorbent was demonstrated over 4 cycles using NaCl (1.0 M) + HCI (0.5 MI) solution mixture to de-extract the U(VI). The results show that the PGTFS-COOH tested is very promising for the recovery of U(VI) from water and wastewater. (C) 2008 Elsevier Ltd. All rights reserved.

Keywords: Activated Carbon, Adsorption, Aqueous-Solutions, Biosorption, Desorption, Equilibrium, Graft Copolymerization, Isotherm, Isotherm, Models, Removal, Sorption, Tamarind Fruit Shell, Uranium(VI) Adsorption

? Guerra, D.L., Airoldi, C. and Viana, R.R. (2010), Modification of hectorite by organofunctionalization for use in removing U(VI) from aqueous media: Thermodynamic approach. Journal of Environmental Radioactivity, 101 (2), 122-133.

Full Text: 2010\J Env Rad101, 122.pdf

Abstract: A Hectorite sample (H) has been chemically modified with N-propyldiethylenetrimethoxysilane and bis[3-(triethoxysilyl)propyl]tetrasulfide. The resulting materials (H-3TPT and H-NPTM) have been characterized through elemental analysis, X-ray diffractometry, carbon nuclear magnetic resonance in the solid state, textural analysis, and thermogravimetric analysis. The adsorption experiments were performed under batch process with pH, ionic strength, contact time, and uranyl concentration as variables. The attached basic centers adsorbed uranyl cation to give maxima adsorption capacity of 5.55±0.21, 14.86±0.05, and 18.99±0.05×10^-3 mmol g^-1 for H, H-3TPT, and H-NPTM, respectively. From calorimetric determinations the quantitative thermal effects for UO₂²⁺/center interactions gave exothermic enthalpy (ΔH-int = -6.90 to -7.88 kJ mol^-1), negative Gibbs free energy (Δ(int)G = -22.34 to -24.56 kJ mol^-1), and positive entropy (ΔS-int = 51.80-56.00J K^-1 mol^-1). These thermodynamic data confirmed the energetically favorable condition of such interaction solid/liquid for all systems. (C) 2009 Published by Elsevier Ltd.

Keywords: Adsorption, Adsorption Capacity, Analysis, Approach, Batch, Batch Process, Capacity, Carbon, Cation, Concentration, Data, Energy, Enthalpy, Entropy, Exothermic, Experiments, Gibbs Free Energy, Interaction, Ionic Strength, Magnetic, Magnetic Resonance, Media, Modification, Modified, pH, State, Strength, Systems, Thermodynamic, Thermodynamic Data, Time, U(VI), X-Ray

? Wang, J.S., Hu, X.J., Liu, Y.G., Xie, S.B. and Bao, Z.L. (2010), Biosorption of uranium(VI) by immobilized Aspergillus fumigatus beads. Journal of Environmental Radioactivity, 101 (6), 504-508.

Full Text: 2010\J Env Rad101, 504.pdf

Abstract: Biosorption of uranium(VI) ions by immobilized Aspergillus fumigatus beads was investigated in a batch system. The influences of solution pH, biosorbent dose, U(VI) concentration, and contact time on U(VI) biosorption were studied. The results indicated that the adsorption capacity was strongly affected by the solution pH, the biosorbent dose and initial U(VI) concentration. Optimum biosorption was observed at pH 5.0, biosrobent dose (w/v) 2.5%, initial U(VI) concentration 60 mg L^-1. Biosorption equilibrium was established in 120 min. The adsorption process conformed to the Freunlich and Temkin isothermal adsorption models. The dynamic adsorption model conformed to pseudo-second order model. (C) 2010 Elsevier Ltd. All rights reserved.

Keywords: Adsorption, Adsorption Capacity, Alginate Beads, Aqueous-Solutions, Aspergillus Fumigatus, Batch, Batch System, Beads, Biomass, Biosorbent, Biosorption, Capacity, Concentration, Dynamic, Equilibrium, Fungus Trametes-Versicolor, Heavy-Metals, Immobilized, Immobilized Beads, Ions, Isothermal, Isothermal Adsorption, L1, Model, Models, pH, Pseudo Second Order, Pseudo-Second Order, Pseudo-Second Order Model, Pseudo-Second-Order, Pycnoporus-Sanguineus, Removal, Rights, Si, Solution, U, Uranium, Uranium(VI)

? Zhang, H., Yu, X.J., Chen, L., Jing, Y.J. and Ge, Z.W. (2010), Study of Ni-63 adsorption on NKF-6 zeolite. Journal of Environmental Radioactivity, 101 (12), 1061-1069.

Full Text: 2010\J Env Rad101, 1061.pdf

Abstract: The adsorption of Ni-63 from aqueous solutions using NKF-6 zeolite was investigated by a batch technique under ambient conditions. The adsorption was investigated as a function of contact time, pH, ionic strength, foreign ions, humic substances (FA/HA) and temperature. The kinetic adsorption was well described by the pseudo-second-order rate equation. The adsorption of Ni-63 on NKF-6 zeolite was strongly dependent on pH and ionic strength, and the adsorption of Ni-63 increased with increasing NKF-6 zeolite content. At low pH values, the presence of FA enhanced the adsorption of Ni-63 on NKF-6 zeolite, but the presence of HA had no drastic effect. At high pH values, the presence of FA or HA decreased the adsorption of Ni-63 on NKF-6 zeolite. The adsorption isotherms were well represented by the Langmuir model. The thermodynamic parameters (i.e., Delta H-0, Delta S-0 and Delta G(0)) for the adsorption of Ni-63 were determined from the temperature dependent isotherms at 293.15, 313.15 and 333.15 K, respectively, and the results indicate that the adsorption reaction was favored at high temperature. The results suggest that the adsorption process of Ni-63 on NKF-6 zeolite is spontaneous and endothermic. (C) 2010 Elsevier Ltd. All rights reserved.

Keywords: Adsorption, Adsorption Isotherms, Aqueous Solutions, Aqueous-Solution, Batch, Batch Technique, Contact Time, Fa, Foreign Ions, Fulvic-Acid, Gmz Bentonite, Ha, High Temperature, Humic Substances, Humic-Acid, Ionic-Strength, Isotherms, Kinetic, Kinetic Adsorption, Langmuir, Langmuir Model, Model, Multiwalled Carbon Nanotubes, Mx-80 Bentonite, Na-Rectorite, Ni-63, Nkf-6 Zeolite, pH, Process, Pseudo Second Order, Pseudo-Second-Order, Spectroscopy Methods, Temperature, Thermodynamic, Thermodynamic Parameters, Zeolite