Study of absorption, emission and EDS properties of Pr3+ incorporated in a SiO2 matrix by sol-gel method

Abstract

This paper deals with a study of the oxidation processes of the PbS-sodium isopropyl xanthate system in alkaline conditions (pH 8, similar to flotation circuits Pb-Cu) by using cyclic voltammetry and Electrochemical Impedance Spectroscopy (EIS). Three oxidation peaks are identified in the voltammograms that correspond to reactions previously reported in the literature. A plot of the differential capacitance of the double layer vs. potential gives a potential of zero charge (PZC) of -0.31 V vs. SCE for the system, that coincides with an oxidation peak attributed to the adsorption of xanthate. EIS at PZC for different xanthate concentrations evidence an adsorption processes via a charge transfer mechanism under diffusional control. EIS data at potentials more positive than PZC display an inductive loop that is related to a charge transfer processes involving the reaction of the adsorbed intermediates with the consequent modification of the PbS-sodium isopropyl xanthate interface. "The Electrochemical Society.",,,,,,"10.1149/1.3660641",,,"http://hdl.handle.net/20.500.12104/44812","http://www.scopus.com/inward/record.url?eid=2-s2.0-84879442901&partnerID=40&md5=ebd639cd709da6ac78e5e9ccfa345dda",,,,,,"1",,"ECS Transactions",,"463

470",,"36",,"Scopus",,,,,,,,,,,,"Study of adsorption of sodium isopropyl xanthate on galena",,"Conference Paper" "46596","123456789/35008",,"Medina-Gutiérrez, C., Universidad de Guadalajara, Campus Universitario Los Lagos, Fracc. Paseo de la Montaña, C. P. 47460, Lagos de Moreno, Jal., Mexico; Frausto-Reyes, C., Centro de Investigaciones en óptica, A. C., Unidad Aguascalientes, Apartado Postal # 507, C. P. 20200, Aguascalientes, Mexico; Medina-Valtierra, J., Institute Tecnológico de Aguascalientes, Fracc. Bona Gens, Aguascalientes, Ags., C. P. 20256, Mexico; Jaimes-Reategui, R., Universidad de Guadalajara, Campus Universitario Los Lagos, Fracc. Paseo de la Montaña, C. P. 47460, Lagos de Moreno, Jal., Mexico; García-López, H., Universidad de Guadalajara, Campus Universitario Los Lagos, Fracc. Paseo de la Montaña, C. P. 47460, Lagos de Moreno, Jal., Mexico; Molina-Contreras, J.R., Institute Tecnológico de Aguascalientes, Fracc. Bona Gens, Aguascalientes, Ags., C. P. 20256, Mexico",,"Medina-Gutierrez, C.

Frausto-Reyes, C.

Medina-Valtierra, J.

Jaimes-Reategui, R.

García-Lopez, H.

Molina-Contreras, J.R.",,"2006",,"A micro-Raman system is used to study the ?-carotene of dry and fresh carrot samples in environments with variations of the temperature between 16°C and 120°C. It is shown that the Raman peaks intensities of the dry sample diminish considerably, due to the strong degradation of the ?-carotene with the increment of the temperature. Also, for the fresh sample in deionized water, the Raman peaks intensities of the ?-carotene, starting from 40 to 50°C, diminish, due to its degradation and diffusion on the surface of the sample and in the water. The same tendency is observed for the ?-carotene of the carrot juice.",,,,,,"10.1117/12.674466",,,"http://hdl.handle.net/20.500.12104/44817","http://www.scopus.com/inward/record.url?eid=2-s2.0-33645229998&partnerID=40&md5=9dceaf60a539e711a486b00aff3f0914",,,,,,,,"Proceedings of SPIE - The International Society for Optical Engineering",,,,"6046",,"Scopus",,,,,,"?-carotene; Raman spectroscopy; Temperature",,,,,,"Study of temperature effect in ?-carotene of carrot by Raman spectroscopy",,"Conference Paper" "46589","123456789/35008",,"Gómez-Miranda, M., Physics Departement Universidad Autónoma Metropolitana- Iztapalapa, México, PO BOX 55-532Distrito Federal, Mexico; Velásquez Ordoñez, C., Universidad de Guadalajara, Centro Universitario de Los Valles Centro de Investigation en Nanociencia y Nanotecnologia de la, Depto. de Ciencias Naturales y Exactas Ameca Jal., Mexico; Sosa Fonseca, R.S., Physics Departement Universidad Autónoma Metropolitana- Iztapalapa, México, PO BOX 55-532Distrito Federal, Mexico",,"Gomez-Miranda, M.

Velasquez Ordonez, C.

Sosa Fonseca, R.S.",,"2015",,"The optical response of the Pr3+ ions doped monolith of SiO2 prepared by sol-gel method was investigated by absorption and emission spectra. The absorption spectrum shows some typical lines of Pr3+, with these data was made the diagram levels corresponding to SiO2: Pr3+. The emission spectra were taken at 225 nm and 240 nm of wavelength of excitation was measured. In that there are reabsorption line at 423 of the Pr3+ ions in the emission host, that means that some kind of host-ion interactions exist. Red and NIR emission at 612 nm, 652 nm, 711 and 728 nm, respectively, from Pr3+ ions in SiO2 was observed. The transition 1S03P2 at 425 nm is observed because an effective radiative transfer between the silicate glasses host and the praseodymium ions is observed and discussed. " Published under licence by IOP Publishing Ltd.