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1.
Environ Monit Assess ; 190(7): 431, 2018 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-29946748

RESUMEN

The potential use of different hard and soft parts (otolith, scale, eye lens, dorsal spine, vertebral bone, muscle, and liver) of Rutilus kutum for biomonitoring of 13 major and trace elements (Br, Ca, Cl, Cu, Fe, K, Mg, Mn, Na, P, S, Sr, and Zn) was evaluated, for the first time. The specimens were sampled from three sampling sites in the Southern Caspian Sea in May 2016. Twenty specimens were collected from each site. The elements' concentrations in the samples were measured by proton-induced X-ray emission (PIXE). In all the hard tissues, except for eye lens, Ca was the most abundant element, whereas Fe was among the least abundant elements. The orders of element occurrence in the two soft tissues were largely similar. Ca, Fe, S, Cl, and K could be detected in all the selected tissues, while Br was detectable only in otolith. Minor similarities among the tissues were identified in the case of eye lens (concerning P, S, and Zn) and liver (in terms of Cl, Fe, and K), whereas, in the case of Sr and Ca, otolith shows the maximum distance. In general, it can be concluded that all the studied hard parts, except for eye lens, may offer alternatives for biomonitoring of Ca, Cl, Fe, K, and S in the southern Caspian Sea. The scales and spines represent a potential non-lethal alternative to the other hard parts.


Asunto(s)
Monitoreo del Ambiente , Oligoelementos/análisis , Animales , Cyprinidae
2.
Environ Monit Assess ; 186(11): 7505-12, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25027779

RESUMEN

In this study, the proton-induced X-ray emission (PIXE) technique has been applied to measure the elemental composition and concentrations of particulate matter of 220 samples of aerosols in Tehran's atmosphere within a 450-day time interval starting from March 2009 and ending in June 2010, covering all four seasons. PIXE analysis shows the samples are comprised of various elements including Al, Si, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Br, Rb, Sr, and Pb. Also, to obtain more information about the sources of pollution and to identify the major sources of urban particulate matter, principal component analysis (PCA) was used. Furthermore, micro-PIXE was performed to study individual aerosols in some samples. Results revealed that the concentration of elements originating from vehicle emissions increases three times in winter; whereas the concentration of elements with soil origin remains constant. Based on wind rose maps, it is inferred that the high concentrations of the elements Al, Si, K, Ca, Ti, Mn, and Fe are associated with natural dust brought by winds into Tehran from the west.


Asunto(s)
Aerosoles/análisis , Contaminantes Atmosféricos/análisis , Atmósfera/química , Monitoreo del Ambiente/métodos , Polvo/análisis , Irán , Material Particulado/análisis , Análisis de Componente Principal , Estaciones del Año , Emisiones de Vehículos/análisis
3.
Ultramicroscopy ; 186: 112-119, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29291437

RESUMEN

An ionoluminescence (IL) spectral imaging system, besides the common MeV ion imaging facilities such as µ-PIXE and µ-RBS, is implemented at the Van de Graaff laboratory of Tehran. A versatile processing software is required to handle the large amount of data concurrently collected in µ-IL and common MeV ion imaging measurements through the respective methodologies. The open-source freeware PyMca, with image processing and multivariate analysis capabilities, is employed to simultaneously process common MeV ion imaging and µ-IL data. Herein, the program was adapted to support the OM_DAQ listmode data format. The appropriate performance of the µ-IL data acquisition system is confirmed through a case study. Moreover, the capabilities of the software for simultaneous analysis of µ-PIXE and µ-RBS experimental data are presented.

4.
Spectrochim Acta A Mol Biomol Spectrosc ; 179: 171-177, 2017 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-28242446

RESUMEN

The unique ionization pattern of MeV-energy ion beam is applied for efficient luminescence analysis of a collection of natural turquoise samples. The considerable penetration depth of tens of micrometer and enhancement of energy deposition with depth, suggests ionoluminescence as an appropriate technique for studying weakly luminescent minerals. Herein, the luminescence induced in deeper parts of turquoise samples is extracted through their relatively transparent adjacent host stones. The resulting intense spectra reveal the vibrational structure of the broad green luminescence band of turquoise which probably originates from O2- centers. Moreover, owing to the applied ionoluminescence approach, red and blue luminescence bands of turquoise were observed which can be ascribed to Fe3+ ions and UO22+ centers respectively. The elemental information of the samples is provided using micro-PIXE analysis technique.

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