Person: Alcolea Palafox, Mauricio
Loading...
First Name
Mauricio
Last Name
Alcolea Palafox
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Ciencias QuÃmicas
Department
QuÃmica FÃsica
Area
QuÃmica FÃsica
Identifiers
17 results
Search Results
Now showing 1 - 10 of 17
Item Synthesis, structural and morphological characterization and photoluminescence study of Y0.9Er0.1−xYbxVO4 materials(Journal of alloys and compounds, 2022) Rapp, M.; Isasi MarÃn, Josefa; Alcolea Palafox, Mauricio; Muñoz Ortiz, T.; Ortiz Rivero, E.Erbium/ytterbium-dopped Y0.9Er0.1−xYbxVO4 samples with x = 0, 0.01, 0.05 and 0.09 were synthesized by hydrothermal synthesis at basic pH with urea addition. For comparison purposes, another sample with x = 0 was also prepared by the solgel method. X-ray diffraction patterns were indexed on the basis to a tetragonal symmetry of space group I41/amd with Z = 4 compatible with a zircon-type, in good agreement with FTIR spectra. Additionally, some of the samples were coated with silica, and the successful coating process was verified in both X-ray diffraction profiles and FTIR spectra. Particles of two different morphologies were found in transmission electron microscopy images of uncoated samples, some spherical with sizes between 14 and 20 nm and others elongated. A shell of ~ 5 nm thickness was also observed in silica covered samples. The relationship between dopant content and the luminescence emission was systematically explored. Erbium-doped samples exhibit bright green fluorescence under stimulation at 360 nm. The substitution of erbium by ytterbium successfully produced an up-conversion emission under stimulation at 808 nm, being able to observe green and red emission bands. The potential use as fluorescent thermometers of erbium/ ytterbium doped samples at 300, 325 and 350 K was finally investigated- Project number: 83
Item Enseñanza de quÃmica con fundamento. Ensayos virtuales(2022) Isasi MarÃn, Josefa; Arquero Avilés, MarÃa Del Rosario; Marco Cuenca, Gonzalo; Fernández-Ramos Humanes, Miguel; Rap diez de la Cortina, MarÃa; MartÃnez Pacheco, Andrea; Gómez Prados, Sergio; Lozano Vilches, Yaiza; Alba Isasi, Pablo; Alba Isasi, Carlos; Marco Arquero, MarÃa; Alba Isasi, MarÃa Teresa; Alcolea Palafox, Mauricio; Espada Morán, Luis; Marco Arquero, Carla; Marco Arquero, Alexia; Herranz Muñoz, Irene; Cáceres Ramos, Silvia; Hernán GarcÃa, Esther; de la Lastra MartÃnez, Jaime; Veas Porlán, Manuel; Pareja GarcÃa, Arturo; GarcÃa Calvo, Elena; Ferreiro de Aguiar, Adriana; Fernández Rivero, Adrian; Gordo Lozano, Marta; Arévalo Cid, Pablo; Boulahya, Khalid; Sánchez Calero, Luisa24 vÃdeos se han elaborado en el desarrollo del trabajo. Estos vÃdeos muestran grabaciones de experimentos sencillos que tratan contenidos de QuÃmica general y su explicación. El trabajo está teniendo una buena aceptación, tal y como lo demuestran las muchas entradas al canal de YouTubehttps://www.youtube.com/channel/UCNG3-lLP2AetT-ksEBC0hAw/video - Project number: PIMCD73/23-24
Item Utilización de la metodologÃa de Simulación clÃnica en la entrevista clÃnica para estudiantes de estudiantes de ciencias de la salud.(2024) MartÃnez Jiménez, Eva MarÃa; Becerro De Bengoa Vallejo, Ricardo; Zaragoza GarcÃa, Ignacio; Posada Moreno, MarÃa Paloma; Alcolea Palafox, Mauricio; Calvo Lobo, César; Pedraza Velasco, MarÃa Lourdes De; Pérez Boal, Eduardo; Casado Hernández, Israel; Soriano Medrano, Alfredo; RodrÃguez Sanz, David; Muñoz Sánchez, José Luis; RodrÃguez Sancho MarÃa José; MartÃnez Jiménez, Eva MarÃa Item Structural and magnetic studies of NiFe2O4 and NiFe2O4@SiO2-Silane agent samples useful for the removal of Cu2+ ions(Journal of Alloys and Compounds, 2022) Ferrer, Carlos; Isasi MarÃn, Josefa; Arévalo, Pablo; Fernández-Ramos, Miguel; Rapp, MarÃa; Alcolea Palafox, Mauricio; Marco, Jose; MartÃn-Hernández, FátimaNickel ferrite samples are currently investigated due to their potential technological applications. For this reason, the optimal synthesis conditions of nickel ferrite samples with small particle size were investigated here. First, a systematic study was carried out using urea as an additive, and varying reaction parameter such as the amount of urea added or the reaction temperature and time. For comparison purposes, another sample was synthesized using potassium hydroxide as an additive. The two pure nickel ferrite samples were coated with silica, functionalizing them with APTES and AEPMDS. X-rays, FTIR, Mössbauer spectroscopy, TEM and Ms vs. H and FC/ZFC curves were used for the characterization of samples and the evaluation of their properties. Square particles with an average size of 21.2 nm were observed in the TEM images of the sample synthesized with urea, while these are spherical of 6.2 nm in the sample prepared with potash. Their subsequent coating and functionalization give rise to an arrangement of particles within interlocking strands whose thickness increases with their size. Ms vs. H curves confirm the almost superparamagnetic behavior of all synthesized powders, although with a slight increase in the coercivity value of the samples prepared with urea. Preliminary tests carried out on the functionalized samples to evaluate the adsorption capacity in aqueous solution and their easy separation in presence of an external magnetic field, confirm that the sample syn thesized with urea and functionalized with AEPDMS is the most efficient for the Cu2+ ions removal.Item Synthesis of new non-covered and silica-covered Y0.9Tm0.1-xYbxVO4 nanophosphors with emission in the visible and NIR ranges(Journal of Luminescence, 2023) Lozano, Yaiza; Fernández-Ramos, Miguel; Rapp, MarÃa; Alcolea Palafox, Mauricio; Ortiz-Rivero, Elisa; Muñoz-Ortiz, Tamara; Isasi MarÃn, JosefaThe development of new materials of interest in the bioimaging field is a relevant topic in current research. We present and study here novel non-covered and silica-covered Y0.9Tm0.1-xYbxVO4 samples with x = 0, 0.01, 0.05 and 0.09 that were prepared by hydrothermal synthesis. For comparison purposes, the study of Y0.9Tm0.1VO4 sample synthesized by the sol-gel method was also included. The relationships between the synthesis method, dopant content and luminescence emission were systematically studied by X-ray diffraction (XRD), FTIR spectroscopy and transmission electron microscopy (TEM). XRD profiles and FTIR spectra confirm the zircon-type structure of the obtained samples. Particles of two different morphologies were found in TEM images of uncoated samples, some spherical with sizes between 42 and 50 nm and others elongated. A shell thickness between 8 and 13 nm was also observed in silica-covered samples. Photoluminescence studies of our samples revealed emission in the NIR and visible ranges. Under excitation at 790 nm, the spectra of thulium-doped samples showed the characteristic emission band of Tm3+ ions. Substitution of thulium by ytterbium successfully led to an up-conversion emission under excitation at 980 nm. Finally, the fluorescent emission study in the NIR of samples that could be more biocompatible demonstrated that they are suitable for use as luminescent thermometers in the physiological temperature range.- Project number: 3
Item Elaboración de material audiovisual de uso en asignaturas prácticas y teórico prácticas de grados y dobles grados que tratan la quÃmica(2023) Isasi MarÃn, Josefa; Alcolea Palafox, Mauricio; Fernández-Ramos Humanes, Miguel; Rapp Diez de la Cortina, MarÃa; Hernán GarcÃa, Esther; de la Lastra MartÃnez, Jaime; Alba Isasi, Pablo; Cáceres Ramos, Silvia; Alba Isasi, Carlos; Herranz Muñoz, Irene; Gordo Lozano, Marta; Luliana Ionita, Andrea; GarcÃa Calvo, Elena; Espada Morán, Luis; Villa GarcÃa, Mª Isabel; MartÃn Gandul, Mª del Carmen; Arévalo Cid, Pablo; Martinez Pacheco, Andrea; Boulahya, Khalid; Marco Arquero, Alexia; Arquero Avilés, MarÃa Del Rosario; Marco Arquero, Carla; Marco Arquero, MarÃa; Marco Cuenca, Gonzalo; Criado GarcÃa, Mª Rosario; Sánchez Calero, LuisaEn el desarrollo del proyecto se han elaborado un total de 25 tutoriales que se convertirán en la guÃa con la que los estudiantes y el profesorado podrán recordar el funcionamiento de todos los softwares utilizados durante el grado (Excel, Origin, Avogadro, ChemSketch, Vesta, X´pert, Checkell, Hyperchem y Fullprof), pudiendo aprender además aquello que no se asimiló bien o lo que nunca se llegó a conocer de estos programas. Este material está ya a disposición de todos los estudiantes de la UCM y de otras universidades en el canal QuimIsasi (https://www.youtube.com/channel/UCNG3-lLP2AetTksEBC0hAw) en el espacio de tÃtulo "Material audiovisual de uso en asignaturas prácticas de grados que tratan la QuÃmica", siendo de suma utilidad para el alumnado que vaya a cursar o que cursará diferentes asignaturas prácticas y teórico-prácticas incluidas en grados y dobles grados que tratan la QuÃmica. El análisis y evaluación del material audiovisual elaborado podrá permitir un aprendizaje más eficaz del manejo de distintos programas que, como se verá, va a permitir llevar a cabo: cálculos generales y estadÃsticos, creación de bases de datos, dibujos de moléculas y su simetrÃa, representación de estructuras de compuestos inorgánicos/orgánicos y cálculos de parámetros de celdilla de esas estructuras o de sus momentos magnéticos. Item Superparamagnetic and light-emitting bifunctional nanocomposites of iron oxide and erbium or thulium doped yttrium orthovanadate(Journal of Alloys and Compounds, 2022) Rapp DÃez de la Cortina, MarÃa; Lozano Vilches, Yaiza; Fernández Ramos, Miguel; Isasi MarÃn, Josefa; Alcolea Palafox, MauricioAdvances in biomedical research have increased interest in obtaining and studying new bifunctional materials for use in theragnostic. Here we describe in detail the preparation of new magnetic-fluorescent bifunctional (Y0.9Ln0.1VO4/Fe3O4)@SiO2 and [(Y0.9Ln0.1VO4 @SiO2)/Fe3O4)@SiO2] nanocomposites with Ln = Er or Tm. In addition, their magnetic and optical properties were carefully analyzed. The influence of Fe3O4 content and the silica shell thickness on the fluorescent emission in the VIS-NIR region of Y0.9Ln0.1VO4 cores was evaluated as well as their use as display systems with the possibility of directing them by means of external magnetic fields. Samples were prepared using wet chemistry methods involving low temperatures and short reaction times. Y0.9Ln0.1VO4 samples that are not easily oxidizable were prepared by a hydrothermal method, while Fe3O4 sample was synthesized by a coprecipitation process in which the mixture of precursors was treated at very low temperature to avoid oxidation. The powder amalgamation of both Y0.9Ln0.1VO4 and Fe3O4 samples was possible due to the silica polymeric network synthetized by a modified Stöber method. The purity of all samples was ensured by XRD and FTIR techniques. Diffraction profiles of Y0.9Ln0.1VO4 samples show diffraction maxima that can be indexed to a tetragonal symmetry of space group I41/amd, compatible with the zircon structure-type of YVO4 host. All reflections present in the diffraction profile of Fe3O4 sample can be indexed to a cubic symmetry of space group Fd3Ì…m, characteristic of an inverse spinel structure-type. The amorphous silica incorporation on the samples was also evaluated by TEM images. Studies of the magnetic behavior and luminescent emission intensity of the investigated samples showed their dependence on both, the silica coating thickness, and the contact or not between the luminescent samples and the magnetic powder.Item Investigation by DFT Methods of the Damage of Human Serum Albumin Including Amino Acid Derivative Schiff Base Zn(II) Complexes by IR-FEL Irradiation(International Journal of Molecular Sciences, 2019) Onami, Yuika; Koya, Ryousuke; Kawasaki, Takayasu; Aizawa, Hiroki; Nakagame, Ryo; Miyagawa, Yoshito; Haraguchi, Tomoyuki; Akitsu, Takashiro; Tsukiyama, Koichi; Alcolea Palafox, MauricioAn infrared free electron laser (IR-FEL) can decompose aggregated proteins by excitation of vibrational bands. In this study, we prepared hybrid materials of protein (human serum albumin; HSA) including several new Schiff base Zn(II) complexes incorporating amino acid (alanine and valine) or dipeptide (gly-gly) derivative moieties, which were synthesized and characterized with UV-vis, circular dichroism (CD), and IR spectra. Density functional theory (DFT) and time dependent DFT (TD-DFT) calculations were also performed to investigate vibrational modes of the Zn(II) complexes. An IR-FEL was used to irradiate HSA as well as hybrid materials of HSA-Zn(II) complexes at wavelengths corresponding to imine C=N, amide I, and amide II bands. Analysis of secondary structures suggested that including a Zn(II) complex into HSA led to the structural change of HSA, resulting in a more fragile structure than the original HSA. The result was one of the characteristic features of vibrational excitation of IR-FEL in contrast to electronic excitation by UV or visible light.- Project number: 6
Item Colección de cuentos de QuÃmica y Genética para el fomento de nuevas vocaciones cientÃficas(2021) Isasi MarÃn, Josefa; Alcolea Palafox, Mauricio; Alba Isasi, MarÃa Teresa; Alba Isasi, Carlos; Alba Isasi, Pablo; Lachiondo Camuñas, MarÃa; Lachiondo Camuñas, Silvia; Sánchez Calero, Luisa; Pozo Lite, MarÃa Luisa Del; Pradillo Orellana, Mónica; Fernández Jiménez, Nadia; Boyano González, Marina; Pérez González, Ana Elisa; Araujo Gutiérrez, Antonio Diego; Ventura Balazar, Gianmarco; Arquero Avilés, MarÃa Del Rosario; Espada Morán, Luis; Marco Cuenca, Gonzalo; Marco Arquero, MarÃa; Villar Tajadura, MarÃa AntoniaSe han escrito diez narraciones que incluyen contenidos básicos de QuÃmica y de Genética. Su lectura y reflexión podrá clarificar conceptos que, en ocasiones, se aprenden sin entender su verdadero significado y, tal entendimiento, podrá contribuir a incrementar el interés por la ciencia y al fomento de nuevas vocaciones cientÃficas. - Project number: 229
Item Ciencia on-line de uso para la prevención y mejora de los efectos del Covid-19(2021) Alcolea Palafox, Mauricio; Isasi MarÃn, Josefa; Calvo Lobo, César; Becerro De Bengoa Vallejo, Ricardo; Pedraza Velasco, MarÃa Lourdes De; RodrÃguez Sanz, David; Alba Aparicio, Valentin; Espada Morán, Luis; Toninelli Rodriguez, Sergio; Martinez Pacheco, Andrea; Fernández-Ramos Humanes, Miguel; Rapp DÃez de la Cortina, MarÃa; Lozano Vilches, Yaiza; Gómez Prados, SergioEl proyecto se planteó con el objetivo general de actuar ante la necesidad de hacer más motivador y comprensible el estudio de alguna de las materias que se imparten hoy en nuestras facultades, poniendo de relieve la prevención y mejora que los efectos del confinamiento por el Covid-19 pudieran acentuarse de cara al futuro.