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In Cambodia, artisanal mining has recently come to a social concern because of the possibility to cause environmental degradation and human health problems. The General Department of Mineral Resources of Cambodia is collecting environmental specimens in mining sites to watch the situation. This time, four water samples from Sampov Loon and one from Memong mining site were sent from the Department to Hiroshima University, Japan, and the samples were analyzed by means of PIXE at the University. A volume of 10 μl from each sample was separated and dropped onto 4 μm polypropylene backing foil. The measurement was carried out by using 2.5 MV single-ended Van de Graaff accelerator. A Si(Li) detector (active area, 80mm²; sensitive depth, 5mm; Be-window's thickness, 25 μm; resolution, 167 eV fwhm at 5.9 keV) was used for both of in vacuo PIXE and non-vacuum external beam PIXE measurement. A computer code PIXS was used for the quantification. The result indicates that there are at least two kinds of water in Sampov Loon and one of them possibly represents polluted condition.

X-ray Emission Techniques (EDXRF) and External Proton Induced X-ray Emission Technique (PIXE) have been used to characterize 13 gem stones obtained from Gem Testing Laboratory, Jaipur, India. Radioisotope sources ¹⁰⁹Cd and ²⁴¹Am were used to excite the gem stones to generate K and L X-rays in the low and high Z region of the periodic table to investigate trace element inclusions besides the main matrix. A proton beam of 4 MeV energy and current of 8 nA intensity were extracted from the FOTIA (Folded Tandem Ion Accelerator) at VandeGaaff Accelerator, Trombay, Mumbai in air through a Kapton foil of 8 micrometer thick mounted on a Teflon cone. Gem stones such as Labradorite Feldspar, Moonstone Feldspar, Almandine Garnet, Tsavorite Garnet, Apatite, Natural Spinel, Natural Zircon, Spessartine Garnet, Natural Ruby (Lead filled), Natural Ruby were characterized for their elemental profile to see the differences in composition besides the main matrix differences. Elements such as Ca, Ti, V, Cr, Mn, Fe, Cu, Zn, Sr, Y and Zr were detected.

A external microbeam system using polyimide windows has been developed for PIXE (Particle Induced X-ray Emission) analysis in air. A beamline consists of a magnetic quadrupole-doublet lens, cylindrical objective slits and double-deflection scanning coils. Polyimide films with a thickness of 3.5 μm or 7.5 μm were used for the exit windows. Spot sizes in air were measured by beam-induced fluorescence of CsI scintillation plates. A minimum spot size obtained was about 10 μm for a 1.5 MeV proton beam. PIXE-mapping images of a Cu grid were successfully obtained in air.

Proton Induced X-ray Emission, PIXE is a very well established analytical method. This technique of analysis can equally be applied both in vacuum, internal PIXE, and in atmosphere, external PIXE. External PIXE has been applied to material analysis in Van de Graaff laboratory at AEOI using filters and funny filters. Advantages of using these filters have been studied when analysing ancient written documents such as envelopes, inks, and newspapers. This technique clearly demonstrated the differences between new and old inks and papers. More data is needed to show other features of this technique.