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Abstract  

At French spa, La Bourboule, arsenical mineral waters are applicated by several ways. The process and degree of absorption of water are not well known; so, we tried to study absorption, measuring arsenic concentration in the blood and in some organs. On rabbits, thirty minutes after the animal had drunk mineral water, the increase of arsenic concentration in its blood is about twenty times and it is only about three to nine time in lungs, bronchia and traches. On human subjects, it was observed an increase of five times in the blood, two hours after treatment.

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For recent years, the labeling and application of Somatostatin and Its Analogues have been becoming more and more important in the both diagnosis and treatment of a variety of tumors, especially the neuroendocrine tumors. This paper's goals are to deal with the chemical aspects of the radiolabeling of somatostatin and its analogues. It reviews the selected radionuclides and bifunctional chelating agents may be used in the labeling of Somatostatin and its analogues with metal radionuclides. The prospects of application of the Labelled Somatostatin and its analogues are comparatively assessed.

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Radiation treatment in the presence of catalysts such as anatase, P25 and bentonite showed efficient removal of TCE (trichloroethylene) and PCE (perchloroethylene) compared with gamma-irradiation alone. Gamma-ray pretreatment of P25 and bentonite enhanced the decomposition of TCE and PCE, respectively. The change in the catalysts by gamma-rays was characterized by their EPR spectra. For anatase and bentonite, the peaks in the spectra increased significantly, and the pattern of the spectra changed in the case of P25. The relationship between the peaks and pollutant decomposition should be further clarified due to the complexity of the spectra.

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The ability to map boron and hydrogen distributions in the body is paramount to the success of boron neutron capture therapy (BNCT). We investigated treatment-time quantitative mapping of these distributions by detecting (i) 0.48 MeV de-excitation photons from neutron capture by boron-10; (ii) 2.22 MeV photons from neutron capture by hydrogen; and (iii) transmitted neutrons. Monte Carlo simulations reported no detectable difference when 10B in tumour was varied from 0 to 50 ppm, and when the tumour size was varied from 0.0 to 9.5 cm3.

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The effect of thermal treatment on the electrical conductivity was studied for a quasi-one-dimensional organic conductor, (DIMET)2I3 (DIMET=dimethyl(ethylenedithio)tetrathiafulvalene). After heating the samples up to a temperature between 340 and 370 K, the electric resistivity was measured at low temperature down to 2 K and under pressure up to 1.6 Gpa. (DIMET)2I3 shows irreversible decrease in the electric resistivity between 350 and 356 K on heating. It was found that the heating above 350 K suppresses the spin-density-wave transition at 40 K and another metal-insulator transition appears at 18 K.

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Carbon nanotubes (CNTs) were synthesized using a chemical vapour deposition (CVD) method. The properties of CNTs before and after vacuum annealing treatment were studied using scanning electron microscopy (SEM), scanning tunneling microscopy/spectroscopy (STM/STS) and thermogravimetric analysis (TG). Field emission characteristics of the raw and vacuum heated (up to 650C) carbon nanotube films (CNTFs) were measured in a diode system. Emissive properties of the CNTFs depend on an annealing process during which structural changes in the nanotube walls take place. The structural changes, related to saturation of dangling bonds, influence a rate of oxidation process and also improve the emissive field properties.

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This paper describes ongoing research into the multi-physics model development of an electrorefining process for the treatment of spent nuclear fuel. A forced convection of molten eutectic (LiCl–KCl) electrolyte in an electrorefining cell is considered to establish an appropriate electro-fluid model within the 3-dimensional framework of a conventional computational fluid dynamic model. This computational platform includes the electrochemical reaction rate of charge transfer kinetics which is described by a Butler–Volmer equation, while mass transport is considered using an ionic transport equation. The coupling of the local overpotential distribution and uranium concentration gradient makes it possible to predict the local current density distribution at the electrode surfaces.

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A system made up by a Zymark robot and a separation automate preteats spent fuel samples and monitors a tri-n-octylphosphine oxide column extraction chromatographic procedure in order to isolate and purify uranium and plutonium present in the samples, prior to the spectrometric measurements. Up to 16 subsamples of spent fuel in dried or solution form are handled simultaneously in a completely unattended mode. The throughput of the robotized analytical procedure has increased by a factor of 3 compared to the earlier manual procedure without loss in the quality of the chemical treatment and of the mass- and -spectrometric measurements.

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The influence of thermal treatments on photoluminescence spectra of several minerals has been investigated. By applying step-wise heating, new luminescence centres were detected which had been not previously recognized in the corresponding minerals. Luminsecence centres appearing as result of valence changing during oxidizing heating include: (i)  (UO2)2+ as a result of nonluminescent U6+ transformation in zircon, barite, francolite and chert; (ii)  Eu2+ as a result of nonluminescent Eu+ transformation in barite. Luminescence centres which were most stable under thermal treatment were Fe3+ in zircon and Mn2+ in barite. Luminescence centres with similar spectral-kinetic properties but with different thermal stability which allowed them to be separated and properly identified were different metaloxygen complexes (MeOn)m− in zircon.

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Li-, Na-, K-, Rb- and Cs-montmorillonites were saturated with benzidine, these organo-clay complexes heated under vacuum to 200°C and IR spectra recorded at various temperatures. Benzidine is mostly bound to interlayer cations through water molecules, except in Cs-clay where bonding to hydrophobic water and to water molecules which are hydrogen bonded to the oxygen plane predominates. During the thermal treatment water is lost and alkali, cations coordinate directly with benzidine. In Cs-, and to some extent also in Rb- and K-montmorillonite, benzidine is oxidized to semiquinone and quinoidal cation during the thermal treatment.

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