L-shell ionization of Cd: Structure of the x-ray emission spectrum

The cadmium L x-ray spectrum induced by electron impact was analyzed in detail. The measurements were performed on a bulk pure sample using a commercial wavelength dispersive spectrometer, and the spectrum was processed with a parameter optimization method previously developed. This procedure permitted the determination of characteristic energies, relative transition probabilities and natural linewidths for this element. The results obtained here were compared to the data found in the literature, when available. Spectral structures related to satellite and radiative Auger Effect emissions were also analyzed, assessing energy shifts and relative intensities. Some of these parameters were determined for the first time, even in overlapping peaks and weak transitions, which was possible due to the robustness of the spectral processing method used.Fil: Fernandez, Francisco. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; ArgentinaFil: Sepúlveda, A.. Universidad Tecnológica Metropolitana; ChileFil: Trincavelli, Jorge Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; ArgentinaFil: Castellano, Gustavo Eugenio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; Argentin

Experimental x-ray-production cross sections for the M3, M4, and M5 subshells of Pt and Au by electron impact

X-ray-production cross sections for M3, M4, and M5 subshells of Pt and Au by electron impact were experimentally determined at incident energies ranging between 2.8 and 28 keV. To this purpose, Pt and Au thick targets were irradiated by an electron beam in a field-emission-gun scanning electron microscope, and the x-ray-emission spectra were recorded with an energy-dispersive spectrometer. The x-ray-production cross sections were obtained as a result of the spectral processing performed through a careful parameter optimization routine previously developed, which involves an analytical function for the prediction of the experimental spectra, on the basis of ionization depth distribution functions. The results are compared with the scarce data available in the literature.Fil: Carreras, Alejo Cristian. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; ArgentinaFil: Castellano, Gustavo Eugenio. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; ArgentinaFil: Segui Osorio, Silvina Inda Maria. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; ArgentinaFil: Trincavelli, Jorge Carlos. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; Argentin

Nafion membrane channel structure studied by small-angle X-ray scattering and Monte Carlo simulations

The structure of Nafion 117 membranes was studied through SAXS experiments and 2D pattern simulations. Measurements were taken for different moisture conditions by synchrotron radiation, and for different temperatures through X-ray tube irradiation. The experimental profiles were fitted through simulations based on a new structural model including: the amorphous polymer matrix, polymer crystallites, and inverse core-shell type channels conformed by water cylinders and sulfonic chains. The geometrical parameters intervening in the simulation of the SAXS patterns were optimized for each experimental condition. This approach allowed the proper description of the experimental SAXS profiles for the various moisture conditions studied. In addition, a recent lamelar model was also included in the assessments, and the corresponding performances were discussed.Fil: Fernandez Bordin, Santiago Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; ArgentinaFil: Andrada, Heber Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; ArgentinaFil: Carreras, Alejo Cristian. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; ArgentinaFil: Castellano, Gustavo Eugenio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; ArgentinaFil: Oliveira, Rafael Gustavo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones en Química Biológica de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Centro de Investigaciones en Química Biológica de Córdoba; ArgentinaFil: Galván Josa, Víctor Martín. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; Argentin

Structure of the Ru, Ag and Te L X-ray emission spectra

Versión aceptada del artículo; finalmente publicada en: Rodriguez Cabello, Tabatha Pamela; Sepulveda Peñaloza, Andres Humberto; Carreras, Alejo Cristian; Castellano, Gustavo Eugenio; Trincavelli, Jorge Carlos; Structure of the Ru, Ag and Te L X-ray emission spectra; Royal Society of Chemistry; Journal of Analytical Atomic Spectrometry; 31; 3; 2016; 780-789Fil: Rodríguez Cabello, Tabatha Pamela. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentina.Fil: Rodríguez Cabello, Tabatha Pamela. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Física Enrique Gaviola; Argentina.Fil: Rodríguez Cabello, Tabatha Pamela. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; Argentina.Fil: Sepúlveda Peñaloza, Andrés Humberto. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentina.Fil: Sepúlveda Peñaloza, Andrés Humberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Física Enrique Gaviola; Argentina.Fil: Sepúlveda Peñaloza, Andrés Humberto. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; Argentina.Fil: Carreras, Alejo Cristian. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentina.Fil: Carreras, Alejo Cristian. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Física Enrique Gaviola; Argentina.Fil: Carreras, Alejo Cristian. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; Argentina.Fil: Castellano, Gustavo Eugenio. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentina.Fil: Castellano, Gustavo Eugenio. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Física Enrique Gaviola; Argentina.Fil: Castellano, Gustavo Eugenio. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; Argentina.Fil: Trincavelli, Jorge Carlos. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentina.Fil: Trincavelli, Jorge Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Física Enrique Gaviola; Argentina.The emission of X-rays in atomic transitions from L-shell vacancy states of Ru, Ag and Te induced by electron incidence was studied. To this end, L X-ray spectra were measured with a wavelength dispersive spectrometer, and processed by a parameter optimization method previously developed. A large set of atomic parameters corresponding to diagram transitions, such as relative transition probabilities, characteristic energies and natural linewidths of the three elements, were determined. The results obtained are compared to the data found in the literature, when available. In general terms a good agreement was observed, supporting recent calculations based on the framework of the relativistic many-body problem in atoms. Spectral structures related to satellite and radiative Auger emissions were also analyzed, and energy shifts and relative intensities were determined. Many of these parameters were determined for the first time, which was possible due to the robustness of the spectral processing method used, even in the cases of peak overlapping and weak transitions.info:eu-repo/semantics/acceptedVersionFil: Rodríguez Cabello, Tabatha Pamela. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentina.Fil: Rodríguez Cabello, Tabatha Pamela. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Física Enrique Gaviola; Argentina.Fil: Rodríguez Cabello, Tabatha Pamela. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; Argentina.Fil: Sepúlveda Peñaloza, Andrés Humberto. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentina.Fil: Sepúlveda Peñaloza, Andrés Humberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Física Enrique Gaviola; Argentina.Fil: Sepúlveda Peñaloza, Andrés Humberto. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; Argentina.Fil: Carreras, Alejo Cristian. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentina.Fil: Carreras, Alejo Cristian. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Física Enrique Gaviola; Argentina.Fil: Carreras, Alejo Cristian. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; Argentina.Fil: Castellano, Gustavo Eugenio. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentina.Fil: Castellano, Gustavo Eugenio. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Física Enrique Gaviola; Argentina.Fil: Castellano, Gustavo Eugenio. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; Argentina.Fil: Trincavelli, Jorge Carlos. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentina.Fil: Trincavelli, Jorge Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Física Enrique Gaviola; Argentina.Física Atómica, Molecular y Química (física de átomos y moléculas incluyendo colisión, interacción con radiación, resonancia magnética, Moessbauer Efecto.

Chemical and mineralogical characterization of Aguada Portezuelo pottery from Catamarca, north-western Argentina: PIXE, XRD and SEM-EDS studies applied to surface pre- and post-firing paints, slips and pastes

Particle-induced X-ray emission (PIXE), X-ray diffraction (XRD), electron microprobe analysis (EDS) and scanning electron microscopy (SEM) analytical techniques were used to characterize surface paints in pre- and post-fired Aguada Portezuelo decorated pottery. Surface paintings in black, white, red, brown, burgundy and ochre were analysed. Major, minor and trace elements were detected by PIXE, whereas XRD and SEM-EDS gave information on the main mineral phases and the characteristic morphology for each analysed pigment. The results obtained indicate that the main colour groups can be easily discriminated by PIXE, and they are characterized by only one pigment for each colour: hematite (red) and manganese mineral oxides (black), respectively, whereas white pigments are characterized by calcite, ghelenite and gypsum.Fil: de la Fuente, Guillermo Adrian. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones y Transferencia de Catamarca. Universidad Nacional de Catamarca. Centro de Investigaciones y Transferencia de Catamarca; Argentina. Universidad Nacional de Catamarca. Escuela de Arqueología; ArgentinaFil: Galván Josa, Víctor Martín. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; ArgentinaFil: Castellano, Gustavo Eugenio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; ArgentinaFil: Limandri, Silvina Paola. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; ArgentinaFil: Vera, Sergio David. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones y Transferencia de Catamarca. Universidad Nacional de Catamarca. Centro de Investigaciones y Transferencia de Catamarca; Argentina. Universidad Nacional de Catamarca. Escuela de Arqueología; ArgentinaFil: Días, Johnny Ferraz. Universidade Federal do Rio Grande do Sul; BrasilFil: Suarez, Sergio Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; ArgentinaFil: Bernardi, Guillermo Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; ArgentinaFil: Bertolino, Silvana Raquel Alina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; Argentin

Separate K-line contributions to fluorescence enhancement in electron probe microanalysis

The behaviour of the fluorescence enhancement correction factor in electron probe microanalysis, as a function of incident electron energy and take-off angle, is assessed for different binary samples in a wide range of compositions. Monte Carlo simulations are employed to validate Reed's correction algorithm [S.J.B. Reed, Characteristic fluorescence corrections in electron-probe microanalysis, Br. J. Appl. Phys. 16 (1965) 913-926], by means of estimating the primary excited radiation volume and the volume corresponding to secondary fluorescence generation. Then, Reed's expression for the fluorescence enhancement has been modified to account for Kα and Kβ line contributions separately. It is clearly shown that in certain cases the assignment of all fluorescent contribution to the Kα lines may be inadequate, particularly when trace element analysis imposes an accurate determination of elemental concentrations.Fil: Venosta, Lisandro Francisco. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Castellano, Gustavo Eugenio. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Optimization of parameters in electron probe microanalysis

A method for the refinement of atomic and experimental parameters applicable to several spectroscopic techniques is presented. This kind of procedure, previously used in x-ray diffraction, is shown to be a powerful tool in electron probe microanalysis (EPMA). This method consists of minimizing the differences between an experimental x-ray spectrum and a function proposed to account for the bremsstrahlung and characteristic peaks from the corresponding sample, and also for detection artifacts. This complicated function involves several parameters related to different sources (x-ray production, x-ray attenuation, sample composition, x-ray detection, etc.). Initial values must be supplied for them, and after a numerical iterative procedure is performed, improved values are achieved. Depending on the particular situation, certain parameters may be known a priori, so that they can be fixed, allowing the others to vary. In this way, the method can be used for different purposes: determination of atomic parameters such as fluorescence yields transition rates or photoelectric cross-sections, quantitative standardless analysis, determination of detector characteristics, etc. This work is intended to present the general aspects of the method for refining EPMA parameters, and to give some examples of its application to the aforementioned issues. Even when only EPMA spectra are included in this work, the method can be applied to different spectroscopic techniques, such as x-ray fluorescence, particle-induced x-ray emission, etc. Copyright © 2001 John Wiley & Sons, Ltd.Fil: Bonetto, Rita Dominga. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas "Dr. Jorge J. Ronco". Universidad Nacional de la Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Ciencias Aplicadas; ArgentinaFil: Castellano, Gustavo Eugenio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; ArgentinaFil: Trincavelli, Jorge Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; Argentin

Binding effects in sulfur Kα and Kβ X-ray emission spectra

A systematic study has been carried out in order to investigate the influence of the chemical bond on the occurrence of different sulfur decays to 1s vacancy states induced by electron impact. A number of samples in different oxidation states (+4, +6, 0 and -2) were irradiated in a commercial microscope, acquiring Kα and Kβ spectra for all sulfur oxidation states. Special attention has been paid to the case of emissions associated with decays corresponding to multiple ionizations. An important achievement of the present study is the high resolution obtained in the wavelength-dispersive spectra acquired with a commercial spectrometer.Fil: Sánchez, E.. Universidad Nacional de San Luis; ArgentinaFil: Torres Deluigi, María del Rosario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Química de San Luis. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Instituto de Química de San Luis; ArgentinaFil: Castellano, Gustavo Eugenio. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; Argentin

Monte Carlo simulation of characteristic secondary fluorescence in electron probe microanalysis of homogeneous samples using the splitting technique

Electron probe microanalysis (EPMA) is based on the comparison of characteristic intensities induced by monoenergetic electrons. When the electron beam ionizes inner atomic shells and these ionizations cause the emission of characteristic X-rays, secondary fluorescence can occur, originating from ionizations induced by X-ray photons produced by the primary electron interactions. As detectors are unable to distinguish the origin of these characteristic X-rays, Monte Carlo simulation of radiation transport becomes a determinant tool in the study of this fluorescence enhancement. In this work, characteristic secondary fluorescence enhancement in EPMA has been studied by using the splitting routines offered by PENELOPE 2008 as a variance reduction alternative. This approach is controlled by a single parameter NSPLIT, which represents the desired number of X-ray photon replicas. The dependence of the uncertainties associated with secondary intensities on NSPLIT was studied as a function of the accelerating voltage and the sample composition in a simple binary alloy in which this effect becomes relevant. The achieved efficiencies for the simulated secondary intensities bear a remarkable improvement when increasing the NSPLIT parameter; although in most cases an NSPLIT value of 100 is sufficient, some less likely enhancements may require stronger splitting in order to increase the efficiency associated with the simulation of secondary intensities.Fil: Petaccia, Mauricio Germán. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; ArgentinaFil: Segui Osorio, Silvina Inda Maria. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; ArgentinaFil: Castellano, Gustavo Eugenio. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; Argentin

Mean Atomic Number Quantitative Assessment in Backscattered Electron Imaging

A method for obtaining quantitative mean atomic number images in a scanning electron microscope for different kinds of samples has been developed. The backscattered electron signal is monotonically increasing with the mean atomic number Z, and accordingly Z can be given as a function of the image gray levels. From results obtained from Monte Carlo simulations, an exponential function is fitted to convert the backscattered registered gray levels into a Z image map. Once this fitting was performed, the reproducibility of the Z determination was checked through the acquisition of backscattered electron images from metal and mineral standards. The developed method can be applied to any unknown sample, always controlling the experimental conditions, as shown here for a thin section of a rock in which several unknown mineral phases are present; the results obtained herein are compared to quantitative assessments performed with X-ray spectra from each mineral phase.Fil: Sanchez, Eloy Sebastian. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Química de San Luis. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Instituto de Química de San Luis; ArgentinaFil: Torres Deluigi, María del Rosario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Química de San Luis. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Instituto de Química de San Luis; ArgentinaFil: Castellano, Gustavo Eugenio. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentin