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Several southern magnolia (magnolia grandiflora) tree samples, with known concentrations of mercury, were analyzed using particle induced x-ray emission (PIXE) and neutron activation analysis (NAA). Results from the PIXE measurements indicate that the average mercury absorption percentage was found to be 85 ± 4%. The distribution of mercury was found to be reasonably homogeneous over the sample surface. However, small variations in mercury concentration are most likely caused by the structure of cellulose in the wood. Mercury in the samples appears to be stable to a total integrated charge of 10 μC. Three mercury L-shell x-rays are easily observed in the resulting PIXE spectrum. Using PIXE, the mercury detection limit was calculated to be approximately 1 ppm. With one exception, the measured NAA mercury concentrations were larger than the corresponding mass-based values. The NAA mercury detection limit for the southern magnolia samples was estimated to be about 0.017 ppm (17 ppb).

The Fukushima Daiichi nuclear power plant accident caused radioactive pollution by ¹³¹I, ¹³⁴Cs and ¹³⁷Cs. The surface of the ground was contaminated at a volume of 3 × 10⁷ m³. The government has mandated that the top 5 cm of the contaminated soil be removed and stored, in this way, it is desirable to reduce its volume. Soil samples were collected from a mountain, a rice field and a vegetable field in northern Japan, and the silt was extracted from the muddy water by washing the soil. Next, the silt was sprayed with a solution of cesium carbonate (Cs₂CO₃). We determined the amounts of Al, Si, K and Cs in the silt particles using micro-particle-induced X-ray emission (micro-PIXE) analysis. The silt particles from a vegetable field, a rice field and a mountain were mainly formed from smectite or vermiculite, which absorbs Cs atoms. The measurements at multiple detection angles confirmed that Cs atoms were uniformly absorbed within silt particles less than $10-30\mu \text{m}$ in diameter. This resulted that the radioactive Cs atoms were adsorbed in silt particles within $10-30\mu \text{m}$ of the surface.

Applications of X-ray fluorescence (XRF) spectrometer and electron accelerator are reviewed with regard to the historical development in Mongolia. The first XRF spectrometer was installed at Nuclear Research Laboratory, National University of Mongolia (NUM) in 1975. Since that time, XRF has developed into a suitable multi-elemental analysis technique with many fields of practical applications. In 1996, electron cycle accelerator (facility called Microtron MT22) was established at the Mongolian Academy of Science (MAS). The maximum energy is set to 22 MeV, suitable for routine activation analysis. The photo and neutron induced nuclear reactions and analysis of chemical elements in various samples and structure analysis of semi-precious stones were studied using the accelerator. Nevertheless, the MT22 is not used for particle induced X-ray emission (PIXE) analysis since it is difficult to obtain calibration parameters. In case of Mongolia, collected research samples are sent to Japan and New Zealand for PIXE analysis because this analysis method has higher sensitivity compared to conventional XRF method. In order to develop the X-ray research field in Mongolia, an international conference on X-ray analysis has been held every three years since 2006. Nowadays, there are above 20 laboratories in Mongolia which use the XRF methods and techniques, among them about 80 percent of them are utilized for fields of geology, mining and their industrial control processing and others are used for environment, monitoring control and research studies.

Polycrystalline samples with a nominal composition Ru_1-xSb_xSr₂GdCu₂O_8-d were prepared by a solid state reaction technique. A mixture of RuO₂, Sb₂O₃, Gd₂O₃, SrCO₃ and CuO was used to obtain the samples. We performed X-ray diffraction analyses, DC susceptibility and transport measurements and the studies showed that the samples were almost pure Ru-1212 phase. We also observed that Sb doping reduce the conductivity of the system and the transition temperature decreases with increasing Sb content. This may be due to a distortion of RuO₆ octahedral which is responsible for the increase of holes localization.

W-type hexagonal ferrites having the formula BaCo_2-xMg_xFe₁₆O₂₇ with x = 0, 0.4, 0.8, 1.2, 1.6, 2.0 were synthesized by the chemical coprecipitation method. XRD analysis shows that the structure of all the compositions is W-type hexagonal ferrite. The c/a ratio varies from 5.48 to 5.52, consistent with the standard values. It was observed that the bulk density and X-ray density decrease whereas porosity increases with increasing concentration of Mg²⁺. Room temperature resistivity increases, from 10³ to 10⁷ (Ω cm) by increasing the concentration of Mg²⁺, due to an increased number of grain boundaries. The remanence and saturation magnetization decrease with increasing Mg²⁺ content while coercivity increases as the Mg²⁺ increases according to the relation H_c ∝ 1/r. The measured coercivity values are suitable for use in high frequency applications such as microwave absorber materials.

Physical vapor deposition techniques such vacuum arc plasma deposition — which are very commonly used in thin film technology — appear to hold much promise for the synthesis of nanocrystalline thin films as well as nanoparticles. Monodisperse and spherical titanium oxide (TiO₂) and nitride nanoparticles were produced at room temperature as a cluster beam in the gas phase using a cluster-deposition source. Using the basic principles of the gas condensation method, this study has developed vacuum arc nanoparticle synthesis system. We demonstrate that major process deposition parameter is the pressure in the plasma chamber. This is the major advantage of these techniques over thermal evaporation. Our method affords TiN powders with high specific surface areas exceeding 200m²g${}^{-1}$. TEM micrograph of TiO₂ nanoparticles prepared at an oxygen pressure of 60Pa show an average particle size of 6nm. TiO₂ nanoparticles prepared at an oxygen pressure of 70Pa were observed to not have a reduced average particle size.

Five meso-tetraaryl open-chain pentapyrroles were synthesized and characterized as to their electrochemistry and protonation reactions in nonaqueous media. The investigated compounds are represented as (Ar)₄PPyH₃ where Ar $=m$,$m$-F₂Ph, $p$-BrPh, Ph, $m$,$p$,$m$-(OMe)₃Ph or $p$-MePh and were characterized by UV-vis and ¹H NMR spectroscopy, mass spectrometry and electrochemistry. Cyclic voltammetry was used to measure redox potentials, while protonation involving the conversion of (Ar)₄PPyH₃ to [(Ar)₄PPyH₅]${}^{2+}$ was monitored by UV-vis absorption spectroscopy. Equilibrium constants for proton addition were calculated using the Hill equation. One of the pentapyrroles was also structurally characterized. The electrochemical data, protonation constants and crystal structure were then compared with data for previously examined pentapyrroles and analyzed as a function of the solvent properties and nature of substituents on the meso-phenyl rings of the macrocycle.

Five meso-tetraaryl open-chain pentapyrroles were synthesized and characterized as to their electrochemistry and protonation reactions in nonaqueous media. The investigated compounds are represented as (Ar)₄PPyH₃ where Ar = m,m-F₂Ph, p-BrPh, Ph, m,p,m-(OMe)₃Ph or p-MePh and were characterized by UV-vis and ¹H NMR spectroscopy, mass spectrometry and electrochemistry. Cyclic voltammetry was used to measure redox potentials, while protonation involving the conversion of (Ar)₄PPyH₃ to [(Ar)₄PPyH₅]²⁺ was monitored by UV-vis absorption spectroscopy. Equilibrium constants for proton addition were calculated using the Hill equation. One of the pentapyrroles was also structurally characterized. The electrochemical data, protonation constants and crystal structure were then compared with data for previously examined pentapyrroles and analyzed as a function of the solvent properties and nature of substituents on the meso-phenyl rings of the macrocycle.