Calcium contents of demineralised human cortical bone determined by titrimetric assay and atomic absorption spectrophotometry technique were verified by comparing to neutron activation analysis which has high recovery of more than 90%. Conversion factors determined from the comparison is necessary to correct the calcium content for each technique. Femurs from cadaveric donors were cut into cortical rings and demineralised in 0.5 M hydrochloric acid for varying immersion times. Initial calcium content in the cortical bone measured by titration was 4.57%, only 21% of the measurement by neutron activation analysis; while measured by atomic absorption spectrophotometer was 13.4%, only 61% of neutron activation analysis. By comparing more readings with the measurements by neutron activation analysis with 93% recovery, a conversion factor of 4.83 was verified and applied for the readings by titration and 1.45 for atomic absorption spectrophotometer in calculating the correct calcium contents. The residual calcium content started to reduce after the cortical bone was demineralised in hydrochloric acid for 8 h and reduced to 13% after 24 h. Using the linear relationship, the residual calcium content could be reduced to less than 8% after immersion in hydrochloric acid for 40 h. Atomic absorption spectrophotometry technique is the method of choice for calcium content determination as it is more reliable compared to titrimetric assay.
A study to determine the influence of soil water status on the physiology of rice plant Oryza sativa var. MR220 after panicle initiation stage was carried out at Ladang Merdeka Mulong Lating in the Kemubu Agricultural Development Authority (KADA) area, Kelantan. Five water management treatments imposed on direct seeded rice were; T1. Continuous flooding, T2. Early flooding up to panicle initiation stage followed by saturated (F55-saturated), T3. Early flooding for the first month followed by saturated (F-30 saturated), T4. Continuous saturated, and T5. Continuous field capacity condition throughout the growth stage. The treatments were arranged in Randomized Complete Block Design (RCBD) with four replicates. In-situ stomatal conductance measurement was carried out at 68 DAS (days after seeding) and the elemental analysis of soil and plant samples was carried out using the Instrumental Neutron Activation Analysis (INAA). Results from this study showed significant differences between treatments for soil moisture content and plant moisture content, but no significance different in leaf stomatal conductance. Rice plant moisture, soil moisture and leaf stomatal conductance showed no interaction. Early flooding up to panicle initiation stage followed by saturated (T2: F55-saturated) resulted in higher plant moisture content. Soil plant transfer coefficient was highest in continuous saturated (T4) for nitrogen, early flooding for the first month followed by saturated (T3: F-30 saturated) for potassium, continuous field capacity condition throughout the growth stage (T5) for magnesium, and continuous flooding (T1) for sodium.
Chemical composition of fine (PM2.5) aerosol samples collected for the 5 years period (2001- 2005) using Gent Stacked filter unit sampler at Klang Valley (3 o 10 ’ 30 ’’ N, 101 o 43 ’ 24 ’’ E) were analysed using Neutron Activation Analysis (NAA) and Proton Induced X-ray Emission (PIXE). Results of the study show that the major component of the fine aerosol was black carbon and sulfur with the mass concentration ranged from 4.4 - 6.7µg m -3 and 1.2 - 1.9µg m -3 , respectively. The total fine aerosol mass concentration were in the ranged of 25 - 31µg m -3 with the reconstructed mass was about 50% as relative to the gravimetric mass. Statistical method, factor analysis with varimax approach has been applied to the aerosol composition data for the fingerprint identification. The analysis produces five identified fingerprint represent soil, industry, motor vehicles/biomass burning and Pb and Zn sources. There is also an unidentified source that could be related to unknown industrial activities.
Trace elements, such as As, Co, Cr, Hg, Sb, and Zn, were determined by neutron activation analysis (NAA), whereas Cd, Cu, and Pb were determined by graphite furnace atomic absorption spectroscopy (GFAAS) in clam, crab, prawn, swamp cerith, and mussel samples after digestion by microwave heating under controlled conditions before eluting the solutions through a column of a chelating resin, Chelex-100. The standard used in the determination of percentage volatile elements retained by microwave digestion and also in the activation process was Lobster Hepatopancreas TORT-1, whereas known mixed standards were prepared from nitrate salts to determine the efficiency of the separation procedure at a controlled pH. Mercury and lead detected in crabs exceeded the maximum permissible level. Some species also showed a high affinity toward certain elements, and their levels of accumulation in the tissues of these species corresponded with the concentration of these elements in sediments, especially at sites in the vicinity of an industrial zone.
Neutron activation of Sm-152 offers a method of radiolabeling for the in vivo study of oral dose formulations by gamma scintigraphy. Reproducibility measurements are needed to ensure the robustness of clinical studies. 204 enteric-coated guaifenesin core tablets (10mg of Sm(2)O(3)) were irradiated by thermal neutrons to achieve 1 MBq at 48 h. Administered activities were 0.86±0.03 MBq. Good reproducibility (CV=3.5%) was observed over 24 weeks ensuring that volunteer doses were within the dose reference level of 0.8 mSv.
A study was carried out on the concentration of REEs (Dy, Sm, Eu,Yb, Lu, La and Ce) that are present in the core marine sediments of East Malaysia from three locations at South China Sea and one location each at Sulu Sea and Sulawesi Sea. The sediment samples were collected at a depth of between 49 and 109 m, dried, and crushed to powdery form. The entire core sediments prepared for Instrumental Neutron Activation Analysis (INAA) were weighted approximately 0.0500 g to 0.1000 g for short irradiation and 0.1500 g to 0.2000 g for long irradiation. The samples were irradiated with a thermal neutron flux of 4.0×10(12) cm(-2) s(-1) in a TRIGA Mark II research reactor operated at 750 kW. Blank samples and standard reference materials SL-1 were also irradiated for calibration and quality control purposes. It was found that the concentration of REEs varies in the range from 0.11 to 36.84 mg/kg. The chondrite-normalized REEs for different stations suggest that all the REEs are from similar origins. There was no significant REEs contamination as the enrichment factors normalized for Fe fall in the range of 0.42-2.82.
A study was carried out to determine the concentrations of rare earth elements (REEs) in Linggi river sediments collected from 113 sampling locations. The sediment analysis was performed by Neutron activation analysis (NAA) and Inductively coupled plasma - mass spectrometry (ICP-MS). The results of Linggi river sediment were normalized to "recent" reference shale values. The means of total concentrations of REEs (ΣREE), light REEs (ΣLREE) and heavy REEs (ΣHREE) in Linggi sediment were 241.2, 219.2, and 22.0 mg/kg, respectively, which indicates enrichment compared to ΣREE, ΣLREE and ΣHREE reference shale values. Results obtained from enrichment factors (EF) show no enrichment to moderate enrichment of Linggi sediments, indicating the sources of REEs pollution originated from natural and land-based activities. A similar pattern was observed by comparing the REEs values of Linggi sediments to other references shale values. Ce (δCe) and Eu (δEu) anomalies indicate Linggi sediments showed positive anomaly of Ce whilst negative anomaly of Eu.
A study to measure the concentrations of long-lived radionuclides of the uranium and thorium series in naturally occurring radioactive materials (NORM) wastes was carried out using gamma spectrometry and neutron activation analysis methods. It was found that radionuclides in the NORM wastes of the oil/gas production and ores/minerals processing industries were not in equilibrium. The 226 Ra/ 238 U and 228 Ra/ 232 Th ratios were between 0.001 and 2220 indicating that the concentrations of daughters radionuclides ( 226 Ra, 228 Ra) were very low or very high compared to the parent radionuclides ( 238 U, 232 Th) in the NORM wastes.
Radioactive particle tracking (RPT) has emerged as a promising and versatile technique that can provide rich information about a variety of multiphase flow systems. However, RPT is not an off-the-shelf technique, and thus, users must customize RPT for their applications. This paper presents a simple procedure for preparing radioactive tracer particles created via irradiation with neutrons from the TRIGA Mark II research reactor. The present study focuses on the performance evaluation of encapsulated gold and scandium particles for applications as individual radioactive tracer particles using qualitative and quantitative neutron activation analysis (NAA) and an X-ray microcomputed tomography (X-ray Micro-CT) scanner installed at the Malaysian Nuclear Agency.
Present work shows the development of nuclear technology in Malaysia and highlights its
applications that have been developed by using the instrumental neutron activation analysis
(INAA) method. In addition, present study exhibits a comprehensive review of INAA for
calculation of neutron flux parameters and concentration of elements. The INAA is a
powerful method to analyse the sample which identifies qualitative and quantitative of
elements present in a sample. The INAA is a working instrument with advantages of
experimental simplicity, high accuracy, excellent flexibility with respect to irradiation and
counting conditions, and suitability for computerization. In INAA, sample is irradiated and
measured directly. In practical. INAA is based on an absolute, relative and single-comparator
standardisation method. The INAA has been developed since 1982 when the
TRIGA Mark II reactor of Malaysia has commissioned. The absolute method was less
utilised, the relative method has been used since 1982, and the ko-INAA method is derived
from single-comparator standardization method has been developed since 1996 in Malaysia.
The relative method, because of its advantages, such as high accuracy, easy for using, has
many applications in Malaysia. Currently, local universities and Malaysian Nuclear Agency
(MNA) research reactor use INAA method in Malaysia.
We report herewith the study of fingernail clippings obtained from the residents of Tokyo, Japan. A total of 18 participants with no health problems and occupational exposure to metals were recruited to provide fingernails samples for this study. Through the use of instrumental neutron activation analysis (INAA), 18 elements (Ag, Al, As, Ca, Cl, Co, Cu, Fe, Hg, K, Mg, Mn, Na, S, Sb, Se, V, and Zn) were determined. The results showed that the toxic elements in the fingernails are in the lower range when compared to literature values. There were no chronic exposures to toxic elements such as As and Hg found. The level of Hg found is lower than that reported 20 years ago, possibly due to the strict regulation control in Japan on the release of Hg to the environment. The elements Se and Zn are found to be rather uniformly distributed among participants and are in agreement with results from other countries. There were no significant differences in elemental concentrations due to genders and smoking habits. The overall data from this study showed similar concentrations to those of healthy participants from other countries. Thus, the current data could represent the background level of elemental concentrations in fingernails of residents in Tokyo, which could serve as reference values for future study.
This paper focuses on the evaluation of the k0 method of instrumental neutron activation analysis in biological materials. The method has been applied in multielement analysis of human hair standard reference materials from IAEA, No. 085, No. 086 and from NIES (National Institute for Environmental Sciences) No. 5. Hair samples from people resident in different parts of Malaysia, in addition to a sample from Japan, were analyzed. In addition, human kidney stones from members of the Malaysian population have been analyzed for minor and trace elements. More than 25 elements have been determined. The samples were irradiated in the rotary rack (Lazy Susan) at the TRIGA Mark II reactor of the Malaysian Institute for Nuclear Technology and Research (MINT). The accuracy of the method was ascertained by analysis of other reference materials, including 1573 tomato leaves and 1572 citrus leaves. In this method the deviation of the 1/E1+ alpha epithermal neutron flux distribution from the 1/E law (P/T ratio) for true coincidence effects of the gamma-ray cascade and the HPGe detector efficiency were determined and corrected for.
Over 114 countries in the world grow rice and more than 50 countries have an annual rice production of 100,000 tonnes or more. Asian farmers produce about 90% of the global total rice production. Generally, there are two most common varieties of rice; cultivated and hill rice. Nowadays a lot of agriculture land is contaminated with toxic elements owing to the use of sludge or municipal compost, pesticides, fertilizers and emissions from municipal waste incinerators, car exhausts, residues from metalliferous mines, and smelting industries. The distribution and concentration of several toxic elements in grains particularly rice has lately become a big concern. A study to determine the concentrations of some elements in a few varieties of rice in our local market using Instrumental Neutron Activation Analysis has been performed by Waste and Environmental Technology Division, Malaysian Nuclear Agency. A total of 15 elements were measured. The method was validated by analysing the Standard Reference Material SRM-1568a (Rice Flour) and SRM-1573a (Tomato Leaves) of NIST. The measured concentrations of major and minor elements were analysed in terms of the average intake of nutrient content and comparison of several toxic elements to other studied values.
Qualitative and quantitative analysis of samples require good judgment from the analysts. These two aspects in gamma spectrometric analysis of Proficiency Test and solid radioactive waste samples for the determination of radionuclides are discussed. It is vital to judge and decide what energy peaks belong to which radionuclides prior to the creation of customized radionuclide library for the analysis of specific samples. Corrections due to radionuclide decay and growth, and the half-life assigned to a particular radionuclide in the uranium and thorium series are also discussed. Discussion on judgment to confirm the presence of thorium in food samples based on gamma spectrometry and neutron activation analysis is also provided.
Kidney stone samples of the types calcium oxalate, uric acid, and xanthine were analyzed for their elemental contents by neutron activation analysis to study both the elemental correlation and influence of element on stone precipitation processes. Elements, such as Al, Au, Br, Ca, Cl, Co, Cr, Fe, Hg, I, K, Mg, Na, Sb, Se, Sr, and Zn, were determined quantitatively. Calcium oxalate stones contained higher concentration of all the elements analyzed compared to uric acid or xanthine stones. The concentrations of Cl, Fe, K, Na, Sr, and Zn were relatively higher than Au, Co, Cr, and Sb. A positive correlation exists between Ca and Zn, whereas a negative correlation exists between Sr and Ca. Zinc may play an important role in the formation of calcium oxalate stone.
Effects of cultural practice under different habitats, of well-managed monoculture plantation and growing wild under rubber trees, were studied in Aquilaria malaccensis (Karas) leaves. This study was carried out on Karas growing in these two habitats each from Lipis, Pahang and Sepang, Selangor areas in Malaysia; under the control and induced treatments. The parameters studied include wet and dry weight of 50 matured leaves, iron and zinc elemental contents in leaf, iron and zinc uptakes from soil, and leaf and soil moisture contents. Iron and zinc were analysed in Karas leaves and soil by using Instrumental Neutron Activation Analysis (INAA) technique.
Medicinal herb preparations prescribed for specific treatment purposes were purchased from markets and were analyzed by instrumental neutron activation analysis with k0 standardization. Then, 500-700 mg of each sample was pelletized under a pressure of six tones and irradiated together with monitors for alpha and neutron flux ratio determinations for about 6 h in a thermal flux of 2.29 x 10(12) n/cm2/s. The accuracy of the method was established by analyzing standard reference materials. Twenty-nine elements, Ag, As, Au, Ba, Br, Ca, Ce, Co, Cr, Cs, Eu, Fe, Hf, K, La, Mn, Mo, Na, Rb, Sb, Sc, Se, Sm, Sr, Th, U, Yb, and Zn, were measured in all the samples, and Hg was detected in some samples, with good accuracy and reproducibility. The concentration of elements determined was found to vary depending on the composition of the herbs used. Although the trend linking the element of the medicinal plants to its curative abilities could not be clearly determined, this study showed that the toxic elements found in the samples were below the levels prescribed by health regulations. Nevertheless, such data are important to understand the pharmacological action and the exact mechanisms of action and formation of active constituents for each medicinal plant and to decide the dosage of the herbs used in the final formulation.
An instrumental neutron activation analytical (INAA) technique is used for the determination of thirty elements in five coal samples collected from Kapar power station, imported from Indonesia and Australia. Analyses of the samples are being associated with standards. All irradiations were performed in the nuclear reactor of Malaysia Nuclear Agency (MNA). Samples were counted by Hyper Pure Germanium (HPGe) detector for short period irradiations at MNA, while for the long period irradiations the samples were counted at Universiti Kebangsaan Malaysia (UKM). The concentrations of thirty elements have been determined: The major components are Cl, Ca, Mg, K, Fe, Ti and Na with the mean concentrations in the range between 70±69 ppm- 6100±1639 ppm; and the trace elements are Zr, V, Mn , Sc, Cr, Co, As ,Br ,Rb ,Sb ,Ba , La, Ce, Nd, Sm, Eu, Tb, Yb, Lu, Hf, Th, U and Ta with the mean concentrations in the range between 0.1381±0.0202 - 69.0±2.8 ppm. The results have been compared to the reported data of eight coal samples from the United States and the reported data of Australian bituminous coal.