Syed Mohammod Hossain

Elemental distribution of metals in urban river sediments near an industrial effluent source

To study the compositional trends associated with the spatial and layer wise distribution of heavy metals as well as the sediment response towards the untreated chemical wastes, we have analyzed river (Buriganga, Bangladesh) sediments by instrumental neutron activation analysis (INAA) and energy dispersive X-ray fluorescence (EDXRF). In nine sediment samples 27 elements were determined where Na, Al, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Zn, As, Rb, Cs, La, Ce, Sm, Dy, Hf, Th and U were determined by INAA and Cu, Sr, Ba, Hg and Pb were determined by EDXRF. Pollution level and the origin of pollutants were evaluated by the aid of geo-accumulation index (Igeo), enrichment factor (EF), pollution load index (PLI) and the inter-element correlation analysis. Major elements are somehow buffered even though the pollution level is severe while the trace metals seem to be highly responsive. Among the heavy metals, Cr is the dominant pollutant, though the pollution level varies systematically with the sampling depth and the distance from the contamination source. Positive linear correlation between Cr and Zn (0.94) ensures the similar anthropogenic source(s) for these two metals, but the sediments of this study respond differently depending upon their geochemical behavior. Rare earth elements (here La, Ce, Sm and Dy), Th and U seem to have crustal origin and the Th/U ratio varies from 2.58 to 4.96.

Arsenic Content in Inactive Tissue:Human Hair and Nail

Nuclear reactor based Neutron Activation Analysis (NAA) method was applied for the determination of arsenic content in human scalp hair, nail and water samples at the south western part of Bangladesh.Average Arsenic (As) content in male and female hair samples were 0.93 �og/g and 3.71 �og/g respectively and also As content in nail samples

Ion-exchange separation of radioiodine and its application to production of 124I by alpha particle induced reactions on antimony

Abstract The basic parameters related to radiochemical separation of iodine from tellurium and antimony by anion-exchange chromatography using the resin Amberlyst A26 were studied. The separation yield of 124I amounted to 96% and the decontamination factor from 121Te and 122Sb was > 104. The method was applied to the production of 124I via the 123Sb(α, 3n) reaction. In an irradiation of 110 mg of natSb2O3 (thickness ∼ 0.08 g/cm2) with 38 MeV α-particles at 1.2 μA beam current for 4 h, corresponding to the beam energy range of Eα = 37 → 27 MeV, the batch yield of 124I obtained was 12.42 MBq and the 125I and 126I impurities amounted to 3.8% and 0.7%, respectively. The experimental batch yield of 124I amounted to 80% of the theoretically calculated value but the level of the radionuclidic impurities were in agreement with the theoretical values. About 96% of the radioiodine was in the form of iodide and the inactive impurities (Te, Sb, Sn) were below the permissible level. Due to the relatively high level of radionuclidic impurity the 124I produced would possibly be useful only for restricted local consumption or for animal experiments.

Fast neutron spectrum unfolding of a TRIGA Mark II reactor and measurement of spectrum-averaged cross sections: integral tests of differential cross sections of neutron threshold reactions

Summary The spectrum of fast neutrons having energies from 0.5 to 20 MeV in the core of the 3MW TRIGA Mark II reactor at Savar, Dhaka, Bangladesh, was unfolded by activating several metal foils to induce threshold nuclear reactions covering the whole spectrum, and then doing necessary iterative calculations utilizing the activation results and the code SULSA. The analysed shape of the spectrum in the TRIGA core was found to be similar to that of the pure 235U-fission spectrum, except for the energies between 0.5 and 1.5 MeV, where it was slightly higher than the fission spectrum. Spectrum-averaged cross sections were determined by integral measurements. The integral values measured in this work were compared with the recommended values for a pure fission spectrum as well as with the integrated data deduced from measured and evaluated excitation functions of a few reactions given in some data files. The good agreement between integral measurements and integrated data in case of well-investigated reactions shows that the fast neutron field at the TRIGA Mark II reactor can be used for validation of evaluated data of neutron threshold reactions.

Cross section measurements of a few threshold reactions induced by fast neutrons from an Am/Be source: integral tests of differential neutron reaction cross section data

Abstract Integral cross sections of the reactions 24Mg(n,p)24Na, 27Al(n,p)27Mg, 27Al(n,α)24Na and 95Mo(n,p)95Nb were measured for the first time with fast neutrons (En > 1.5 MeV) from an Am/Be source. Furthermore, upper cross section limits for the reactions 98Mo(n,α)95Zr and 103Rh(n,p)103Ru were deduced. The results were compared with data calculated using the neutron spectral distribution and the excitation function of each reaction given in the data files and libraries ENDF/B-VII, JEFF-3.1.2, JENDL-4.0, IRDF-2004, TENDL-2010, ROSFOND-2010 and CENDL-3.1. In general, the integral measurement and the integrated value agreed within ± 10%. The fast neutron field (with En > 1.5 MeV) of the Am/Be source is thus well suited for integral tests of excitation functions of neutron threshold reactions.

A trial proficiency test of eight NAA laboratories in Asia using stream sediments

Eight neutron activation analysis research groups from seven countries have participated in a trial proficiency test under the auspices of the Forum for Nuclear Cooperation in Asia. Three stream sediment reference materials were used in the test. A high degree of proficiency was found in the quantification of Co and Sc and more than 20 elements were well quantified by the majority of laboratories. The results support the use of neutron activation analysis, as practised by the participants, for geochemical mapping. The data produced in this study may provide an opportunity to improve the characterisation of the three reference materials.

Analysis of Heavy Metals and Other Elements in Textile Waste Using Neutron Activation Analysis and Atomic Absorption Spectrophotometry

The work focused on the elemental and physicochemical analysis in the textile waste (Effluent and Sludge) where two effluent samples and one sludge sample were collected from Grameen Knit Dyeing Industry (GKDI). Every effluent sample is divided into liquid sample (L1 and L2) and residual sample (R1 and R2). Neutron Activation Analysis (NAA) method used for the elemental analysis. The study revealed that, in the sludge (S) the Sb concentration was found 50.2 mg/L which exceeded the standard. Here Co concentration exceeded the standard. Here the highest Cr and Cd value was found in the (S) which exceeded the standard level. The total alkalinity, hardness and free CO2 level of discharged water was harmful for the environment. From this study it is revealed that the sludge contain high content of heavy metal and other harmful elements. Soda ash method can be applied to reduce the ‘Cr’ concentration. Keywordselement, grameen knit dyeing, neutron, sludge, waste.

Measurement of cross section of the 98Mo(n, γ)99Mo reaction using monochromatic thermal neutrons

Abstract The cross sections of the reaction 98Mo(n, γ)99Mo at neutron energies of 0.0334 eV and 0.0536 eV were measured for the first time using the activation technique, and the resulting values of 116 ± 7 mb and 91 ± 5 mb, respectively, are in good agreement with the JENDL-4 and ENDF/B-VII data files. Those measured values were extrapolated to the energy 0.0253 eV assuming 1/v dependence in the thermal region and the results were compared with the integrally measured values reported in the literature. The new data are thus useful to check the evaluated excitation function.

Experimental cross section for the 152Sm(n, γ)153Sm reaction at 0.0334 eV

Abstract The neutron capture cross section for the 152Sm(n,  γ)153Sm reaction at an energy of 0.0334 eV was measured for the first time using monochromatic neutrons of a powder diffractometer at the TRIGA Mark II nuclear reactor at Dhaka, Bangladesh. The 197Au(n,  γ)198Au reaction was used to monitor the neutron beam intensity. The radioactivity of the products was determined via high resolution γ-ray spectrometry. The obtained cross section value is 184 ± 22 b, which is consistent with both the ENDF/B-VII and TENDL-2012 data libraries. The measured value at 0.0334 eV and the previous data at 0.0536 eV confirm the reliability of the data in the above libraries.

Assessment of rare earth elements, Th and U profile of a site for a potential coal based power plant by instrumental neutron activation analysis

Abstract To study the compositional trends of rare earth elements (REEs: La, Ce, Nd, Sm, Eu, Tb, Dy, Yb, Lu), Th and U in soil samples collected from a site for a potential coal based power plant as well as to conduct a preliminary assessment of environmental impact of the proposed power plant in terms of REEs, Th and U, we have analyzed nine soil samples by instrumental neutron activation analysis. Evaluation of data quality by repeated analysis of IAEA-Soil-7 and IAEA-SL-1 ensures a proper data base-line for the REEs, Th and U abundances of the sampling site. Chondrite-normalized abundance patterns demonstrate the heavy REEs–light rare earth elements and Th–U fractionations in our sample suite along with significant negative Eu anomaly. Thorium/U ratio in our study area ranges from 4.55 to 6.07 which is higher than that of upper continental crust. Preliminary assessment of environmental impact of the proposed power plant is evaluated by taking NIST-SRM-1633b (coal-fly-ash) as contaminant as coal-fly-ash will be the major byproduct of the power plant. Previous literature studies and our prevailing data invoke that proposed power plant will have no severe impact on soil originated biota and on human health in terms of REEs, Th and U abundances. However, the long term effect of excessive REEs, Th and U as well as the other elemental abundances originating from coal-fly-ash should also be taken into an account.