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Abstract  

Since there is no database in Libya defining the intake of the individuals from different essential (minor and trace) and toxic elements provided through food, drinking water and aerosol, a project has been proposed with the cooperation of IAEA to determine the concentration of a number of elements such as Cs, Fe, Cr, Rb, Sc, Se, Co, Zn in the three mentioned sources. Emphasis was placed on the use of nuclear and nuclear-related techniques. In this paper, the primary results are presented for the concentration of minor and trace elements in some vegetables, spices and other foods which are widely used in the Libyan meals. Instrumental neutron activation analysis utilizing a 10 MW water pool reactor and a γ-ray spectroscopy facility was employed. For quality control, certified reference materials were analyzed simultaneosly with the samples which show good agreements compared with the certified data. Emphasis was given to both elements iron and zinc for their importance.

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Abstract  

The paper focuses on the validation of the k 0-method of instrumental neutron activation analysis (k 0-INAA) in the Tajura Nuclear Research Center (TNRC) via the analysis of several certified reference materials. The selected reference materials were: SRM 1572 Citrus Leaves, SRM 1575 Pine Needles, IAEA-A11 Milk Powder, IAEA-V-10 Hay Powder, RM IAEA-Soil-7 and RM IAEA-SL-1 Lake Sediment. The method is based on the PC version Kayzero/Solcoi software package issued by DSM. All the samples, reference materials and monitors were irradiated in various positions of the Tajura reactor with different f and α. The parameters f and α (f — thermal/epithermal neutron flux ratio, α — parameter accounting for the non-ideality of the 1/E epithermal neutron fluence rate distribution) were determined using the bare triple monitor method. The results obtained for all the reference materials are in good agreement with the certified values.

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Abstract  

The application of differential scanning calorimetry (DSC) for purity determination is well documented in literature and is used amongst others in the analysis of pure organic crystalline compounds. The aim of this work is to examine whether the DSC method for purity determination consistently produces values for the purity of polycyclic aromatic hydrocarbons (PAHs) which are sufficiently accurate as required for the certification of reference materials. For this purpose, 34 different existing PAH certified reference materials were tested. The DSC results are shown to be consistent with the results obtained by other methods assessing the organic impurities content in PAHs, like gas chromatography (GC), high performance liquid chromatography (HPLC) and mass spectrometry. Significant differences between the measured values and the certified purity values were observed only in a limited number of cases.

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Abstract  

The k 0-method of standardisation for instrumental neutron activation analysis (INAA) has been used at the OPAL research reactor to determine the elemental composition of three certified reference materials: coal fly ash (SRM 1633b), brick clay (SRM 679) and Montana soil (SRM 2711). Of the 41 certified elements in the three materials, 88 percent were within five percent of the certified values and all determinations were within 15 percent of the certified values. The average difference between the measured and certified values was 0.1 percent, with a standard deviation of 4.1 percent. Since these reference materials are widely used as standards in the analysis of archaeological ceramics by INAA, it has been concluded that the INAA facility in Australia is particularly well-suited for nuclear archaeometry.

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Abstract  

The analysis of mineral contents in space foods is needed to obtain an information on a comprehensive elemental composition as well as the investigation on the effects of human nutrition and health based on the dietary intake of mineral elements. Recently, six items of new Korean space foods (KSFs) such as kimchi, bibimbap, bulgogi, a ramen, a mulberry beverage and a fruit punch which was developed by the KAERI, and the contents of more than 15 elements in the samples were examined by using instrumental neutron activation analysis (INAA). Five biological certified reference materials, NIST SRM were used for analytical quality control. The results were compared with those of common Korean foods reported, and these results will be applied toward the identification of irradiated foods.

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Abstract  

In order to complete having data base of elemental assessment of the east coast of Peninsular Malaysia marine sediments along the South China Sea coasts, trace elements are analyzed and their distribution in marine sediments is undertaken. The present study is done parallel with pervious study on elemental assessment of heavy metals, rare earth elements and actinides in the marine sediments of the east coast of Peninsular Malaysia. Thirty surface sediment samples were collected in this area, including regions of Kelantan, Terengganu, Pahang, Rompin and Johor Baharu. Multielemental analysis was carried out by instrumental neutron activation analysis and inductively coupled plasma atomic emission spectroscopy. In both cases methodology validation was performed by certified reference material analyses. For the surface elemental distributions the enrichment factor values, average I geo and mC d values indicate that the trace elements of the surface sediments are uncontaminated in all sampling stations that are consistent with previous studies results of heavy metals, rare earth elements and actinides.

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Abstract  

Cyclic neutron activation analysis method was conducted for determination of Se in food samples. High accuracy and good precision were proved by analyzing certified reference materials (CRMs) of chicken (GBW10018), rice (GBW10010) and cabbage (GBW10014). The detection limits for the three CRMs reached 0.16, 0.66 and 1.2 ng after 6 cycles at the 161.9 keV γ-peak from 77mSe, under a neutron flux of 9.0 × 1011 n cm−2 s−1 and the conditions of 30 s irradiation, 2 s decay, 30 s counting and 2 s waiting, significantly lower than those of conventional neutron activation analysis without any cycles, which were 0.94, 3.6 and 4.3 ng, respectively.

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Abstract  

A new Compton suppression system (CSS) for the gamma-ray spectrometer portion of the neutron activation analysis (NAA) was set up at the RPI/ITN. The pneumatic transfer system, SIPRA, for short-lived nuclides and cyclic irradiations was improved. A full calibration procedure of the CSS and SIPRA systems was performed. Two certified reference materials, NIST-SRM-1572 (Citrus Leaves) and NIST-SRM-1633a (Coal Fly Ash) were analyzed using the calibration factors. The CSS was instrumental in lowering the detection limits of Cr, Fe, Hg, Rb, Sr, Th and Zn by reducing background and/or spectral interference considerably. The analytical results were evaluated by comparison to the NIST certified values with deviations ranging from 2% to 8% for the above mentioned elements, except Zn ranging from 10% to 15% for biological and environmental samples, respectively.

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Abstract  

The determination of the hydrogen concentrations in coal and metal samples were investigated by using the PGAA system at the HANARO Research Reactor, KAERI. The calibration curve of the hydrogen concentration was obtained from a standard sample and the effects of the interference peaks near the gamma-energy region of hydrogen were investigated. The background in the hydrogen peak of a prompt gamma-ray spectrum was measured for the sample chamber and shielding materials of an atmospheric state. The combined uncertainties estimated for the analysis procedure were in the range of 4–5%. Two kinds of certified reference materials, NIST SRM 1632c (Coal), NIST SRM 173c (Titaniumbase Alloy) and NIST SRM 2453 (Titanium Alloy) were used to verify the accuracy and precision of the measurement. The relative error was in the range of 3–6% and the relative standard deviation were less than 4%.

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Abstract  

In the boron neutron capture therapy, an accurate determination of the boron content in a biological sample is very important. The boron content was investigated with a standard solution of boron which was administered intraperitoneally with a dose of 750 mg/kg body weight into mice induced cancer cells and tumors. The boron content for two types of a sample was compared to the boronophenylalanine for the tumor and the ethylamine derivatives for the induced cancer cell, which were also investigated for their accumulation rate in each organ such as blood, spleen, liver, kidney and brain. An analytical quality control was carried out by using certified reference materials such as Peach Leaves, Apple Leaves and Spinach Leaves. The relative error of the measured values was in good agreement within 2% to the certified values.

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