International Journal of PIXE

A database of PIXE data, which have been accumulated at NMCC, has been constructed. In order to fill up the database, data are newly obtained as many as possible for the kind of samples whose number is small. In addition, the data for different measuring conditions are obtained for several samples. As the number of γ-ray spectrum obtained with a HPGe detector for the purpose of analyzing light elements such as fluorine, is overwhelmingly small in comparison with that of usual PIXE spectra, γ-ray spectrum and elemental concentration of fluorine are obtained as many as possible for food, environmental and hair samples. In addition, the data taken with an in-air PIXE system have been obtained for various samples. As a result, the database involving contents over various research fields is constructed, and it is expected to be useful for researches who make use of analytical techniques. It is expected that this work will give a start to many researchers to participate in the database and to make calibration with each other in order to establish reliable analytical techniques. Moreover, the final goal of the database is to establish the control concentration values for typical samples. As the first step of establishing the control values, average elemental concentration and its standard deviations in hair samples taken from 405 healthy Japanese are obtained and tabulated according to their sex and age.

Seven organs of 24 rats in two different groups of 12 namely experimental and control group were analyzed in order to determine their chemical compositions. Concentration of P, S, Cl, K, Ca, Ti, Fe, Cu, Zn and Br are presented and discussed in this paper. The results were compared by unpaired student t-test for both groups. Difference were considered to be significant when P < 0.05.

The concentration of some trace elements especially potassium calcium, manganese, copper and zinc in the arterial wall tissue for the aneurism patients was studied by PIXE (Proton Induced X-Ray Emission) analysis. Comparing the results with normal aortic wall tissues has been done. All the patients are in the age range of 40-60 years. The samples are derived from 15 patients by surgical operation. The results show the absence of manganese, and decreasing of potassium, Copper and Zinc in the aneurismal tissues. Change in copper concentration in the arterial wall is important in the breakdown of the elastic layer in the aneurism. Elevation of the Calcium and Iron in the aneurism tissues are obtained in the comparison with the control groups. Deficiency or elevation of some elements in the aneurism aorta can be encountered as an indicator in the biopsy analysis.

Information concerning the metallic component of termite mandibles may provide a significant clue for solving the evolutionary theory of termite species. Micro-beam scanning PIXE analysis was used, which is a power tool for detecting elemental components, along with two-dimensional information about the elemental distribution in the analyzed area. The distribution of three specific elements (Mn, Zn and Cl) is the focus of this paper. Especially, Mn and Zn are known to be distinctive factors in taxonomic studies of termite mandibles. In this study, mandibles of 12 species from 5 families were analyzed. Mn was detected in all the termites, except for Mastotermes darwiniensis. On the other hand, only kalotermitid termites had Zn as a predominant metal in the cutting edges. The elemental analysis of these mandibles showed significant information to solve the uncertainty of the phylogenetic relation of termites.

We have measured concentration of multi elements in wild plants collected in Iwate prefecture, Japan. It is found that wild plants contain essential elements such as iron, copper and zinc in the same degree or more in comparison with those in vegetables on the market. It is also found that wild plants contain toxic elements such as chromium and lead in the same degree or less in comparison with vegetables on the market. We took the soils together with the wild plants in nine representative spots and analyzed elemental concentration in them in order to examine the relationship of elemental concentration between plants and soils. Although elemental concentration in each soil has distinguished features, which in wild plants grown on the soil does not directly reflect that in the soil. It is expected that elemental concentration in wild plants is influenced by various factors such as chemical state of existing elements in the soil, pH of the soil, activity of microorganism in the soil, and many other factors.

Industrial wastes are considered as critical factors for disturbing natural ecosystems. The East Calcutta Wetlands, a Ramsar site in West Bengal, India, receives composite industrial effluents, subsequently bringing various kinds of heavy metals throughout the year. This wastewater is being utilized by the local people for pisciculture. The present investigation was carried out to study 1) elemental distribution various components of the wetland and 2) potentiality of water hyacinth in metal amelioration. Water and sediments were collected from four different spots along a wastewater-carrying canal having a stretch of 40km from the source point to the final confluence with river and from the wastewater fed fishpond. Fish (three common carps viz. Labeo rohita, Cirrhinus mrigala and Oreochromis niloticus) and water hyacinth were collected from fishpond mentioned above. Samples were analyzed by PIXE with 3MeV tandem Pelletron. Cr, which is a known metal contaminant of tannery effluent, was detected along with S, K, Ca, Ti, V, Mn, Fe, Ni, Cu, Zn, As, Br, Rb, Sr, Zr. Variable concentrations of some elements like Ca, Fe, Zn in different fish organs was noted in the experiment. Accumulation of Cr, Cu from the water bodies by water hyacinth suggesting their crucial role in heavy metal amelioration.

In order to confirm the availability of an in-air Helium ion induced X-ray emission method for multi-elemental analysis of polytetrafluoroetylene (PTFE) filter sample containing atmospheric particles, NIST urban particulate matter (SRM 1648) collected on PTFE filter using a special small chamber was analyzed by an in-air PIXE method with Helium ions and a proton beam. In addition, we analyzed 10 elements, mixing a standard solution with different concentrations to confirm detection sensitivity of characteristic X-ray peaks. As a result, it is suggested that 1) elements that are lighter than Zn and Pb can be satisfactorily measured using the in-air Helium ion induced X-ray emission method if the amount contained in the filter sample is at least 0.1 mg/L, i.e., 15 ng/cm², 2) the in-air Helium ion induced X-ray emission method is useful as a method for quantitatively analyzing the light elements such as Mg, Al, Si, S and Cl that are important for identifying the behavior and characteristics of atmospheric particles from the PTFE filter sample containing atmospheric particles, and 3) in the case of the PTFE filter sample containing atmospheric particles, it is possible to measure elements from Mg to Pb by means of analysis using Helium ions and protons.

The scope of this study was to determine the concentration and composition of atmospheric particulate matter of aerodynamic diameter < 10 μm (PM₁₀) in the vicinity of coal-fired Ropar thermal power plant near Chandigarh, India. Two sampling sites, one inside the thermal plant and the other, outside the thermal plant were chosen. The elemental analysis was done using Proton Induced X-ray Emission (PIXE) technique. The elements detected at both the sites were common i.e. Si, S, Cl, K, Ca, Ti, Cr, Mn, Fe, Co, Ni, Cu and Zn however, their concentration vary at both the sampling sites. Also, Principal Component (PC) and Enrichment Factor (EF) analysis were done in order to identify the contributing elemental sources towards the particulate matter. Contributing sources to the elements were found not only the emission from the coal-fired thermal power plant but also from other activities like vehicular emissions, household cooking and natural soil dust etc.

Droplet PIXE analysis was applied to the study of radiation effects on soil ecosystem functioning. A paddy soil sample was flooded with well water to prepare soil ecosystem specimens (microcosms), and then the microcosms were chronically exposed to gamma rays at a dose rate of 1 Gy day⁻¹ for 5 days. After the final irradiation, a brownish discoloration was observed in the liquid phases of the irradiated microcosms.To clarify the factors causing the discoloration, minerals in the solutions of the microcosms were analyzed by the droplet PIXE system.Elemental profiles from the XRF spectrum showed marked iron peaks. Exposure of microcosms to gamma rays resulted in a decrease in the iron levels. Since iron is released in the form of Fe(II) from the solid soil to the liquid phase, further determination of the Fe(II) levels was performed. The percentages of Fe(II) to the total iron in the liquid phase of the irradiated microcosms were lower than those of the controls. This result may be caused by the change of Fe species from soluble Fe(II) to insoluble Fe(III) during gamma irradiation, and the Fe(III) species with a brownish color may be associated with the discoloration of the irradiated samples. The conversion from soluble to insoluble forms may also contribute the small amount of dissolved iron in the irradiated microcosms. Iron is an essential trace nutrient for plants, and thus the amount of dissolved iron is one aspect of ecosystem functioning. Effects of gamma radiation on the dissolved iron could involve a change in the soil ecosystem through the depression of iron flux in the long term.

Medicinal herbs have been used from antiquity by humanity. This paper discusses the elemental composition and concentration of ten Indian medicinal plants investigated by particle induced X-ray emission (PIXE) technique. The accuracy and precision of the technique were assured by analyzing three Certified Standard Reference Materials-cabbage (GBW 08504, China), wheat flour (NIST-8436) and bovine liver (NIST-1577b). The elements K, Ca, Mn, Fe, Cu and Zn were found to be present in all the samples in varying concentrations. No toxic heavy metals such as As, Pb and Hg were detected in the studied plants. The range of the elemental concentrations in dry weight has been found to vary from 4.69 × 10⁴mg/kg to 1.81 mg/kg in the plants. The results also show that these plants contain elements of vital importance in man's metabolism and that are needed for growth and developments, prevention and healing of diseases.

Elemental distributions in a post oak leaf was measured using the Particle-Induced X-ray Emission (PIXE) technique and a proton microbeam at energy of 3 MeV with spatial resolution of 10 μm. The elements detected in this sample were Mg, Al, Si, P, S, Cl, K, Ca, Cr, Mn, Fe, Cu, Zn, Br, Rb, and Sr. Among them, spatial differences in the distribution of nine elements were observed between the vascular and mesophyll tissue. Si, Cl, K, and Ca were mostly accumulated in vascular tissue, while Mg, P, S, Cr, and Mn were for the most part accumulated in the mesophyll. The distribution of Ca appeared to follow cell wall contours. The distribution of some of these elements is compared to the function of the elements in living tissue and future possibilities for this type of investigation are discussed.

Proton Induced X-ray Emission (PIXE) and Energy Dispersive X-ray Fluorescence (EDXRF) techniques have been used for elemental characterization of offset printing ink tagged with rare-earth taggants. The offset printing ink was tagged with rare-earth (La, Pr, Nd, Sm, Eu and Gd) thenoyltrifluoroacetonate chelates at about 1000-ppm level for each element separately. Small aliquots (approximately 20 mg) of tagged inks were coated on paper supports in the form of small circles having diameter 10–15 mm each and then analyzed. In the case of PIXE, a proton beam of energy 4 MeV and in the case of EDXRF a radioisotope source of ²⁴¹Am (100 mCi) was used to excite the samples. The PIXE analysis showed well-resolved rare-earth L X-rays and EDXRF analysis showed the K X-rays of rare earths. Satisfactory results to identify and quantify the taggants were achieved.

Beach rock samples collected from South East Coast of Tamilnadu was analyzed by natural radioactive measurements to detect the presence of radioactive elements. PIXE technique was used to obtain elemental composition of beach rocks. The PIXE analysis was carried out using 1.7 MV tandem accelerators with the energy of 2 MeV protons at Indira Gandhi Centre for Atomic Research (IGCAR), Kalpakkam, Tamilnadu, India. The geochemical behavior of the elements in the region is discussed. The occurrence of the radioactive and non-radioactive elements is discussed for their geological significance. The results were used to assess environmental toxicity of heavy metals and radiation hazard in the study area.