74 research outputs found
Análisis temático de la investigación en comportamiento del consumidor: 1968-2000
El trabajo presentado permite ofrecer una panorámica de los temas que han despertado
interés en el estudio del comportamiento del consumidor durante los últimos treinta años.The work presented allows providing an overview of the issues that have aroused interest in the study of consumer behavior over the last thirty years
Single wall carbon nanotubes loaded with Pd and NiPd nanoparticles for H2 sensing at room temperature
Pd and bimetallic Ni50Pd50 nanoparticles protected by polyvinylpyrrolidone (PVP) have been synthesized by the reduction-by-solvent method and deposited on single wall carbon nanotubes (SWCNTs) to be tested as H2 sensors. The SWCNTs were deposited by drop casting from different suspensions. The Pd nanoparticles-based sensors show a very reproducible performance with good sensitivity and very low response times (few seconds) for different H2 concentrations, ranging from 0.2% to 5% vol. H2 in air at atmospheric pressure. The influence of the metal nanoparticle composition, the quality of SWCNTs suspension and the metal loading have been studied, observing that all these parameters play an important role in the H2 sensor performance. Evidence for water formation during the H2 detection on Pd nanoparticles has been found, and its repercussion on the behaviour of the assembled sensors is discussed. The sensor preparation procedure detailed in this work has proven to be simple and reproducible to prepare cost-effective and highly efficient H2 sensors that perform very well under real application conditions.We thank the MINECO, Generalitat Valenciana and FEDER (Projects CTQ2012-31762 and PROMETEO/2009/047) for financial support. A.B.M. thanks the Spanish Ministry Science and Innovation for a Ramón y Cajal fellowship (RyC 2009-03913). Jaime Garcia Aguilar and Izaskun Miguel García also thank the University of Alicante for their fellowships
Pilot Study: Systemic response after lung SBRT analyzing immune Cells phenotyping
To investigate changes of immune-phenotyping values in
patients treated with Stereotactic Body Radiation Therapy
(SBRT) over the lung in order to evaluate the immune
response after radiation therapy
Palladium and Bimetallic Palladium–Nickel Nanoparticles Supported on Multiwalled Carbon Nanotubes: Application to Carbon–Carbon Bond-Forming Reactions in Water
Palladium and bimetallic Pd–Ni nanoparticles (NPs) protected by polyvinylpyrrolidone were prepared by the reduction-by-solvent method and deposited on multiwalled carbon nanotubes (MWCNTs). The catalytic activity of these NPs to carbon–carbon bond-forming reactions was studied by using 0.1 mol % Pd loading, at 120 °C for 1 h and water as a solvent under ligand-free conditions. The Suzuki–Miyaura reaction took place quantitatively for the cross-coupling of 4-bromoanisole with phenylboronic acid, better than those obtained with potassium phenyltrifluoroborate, with Pd50Ni50/MWCNTs as a catalyst and K2CO3 as a base and TBAB as an additive, with good recyclability during 4 cycles with some Ni leaching. The Hiyama reaction of 4-iodoanisole with trimethoxyphenylsilane, under fluoride-free conditions using 50 % aqueous NaOH solution, was performed with Pd/MWCNTs as a catalyst in 83 % yield with low recyclability. For the Mizoroki-Heck reaction 4-iodoanisole and styrene gave the corresponding 4-methoxystilbene quantitatively with Pd50Ni50/MWCNTs using K2CO3 as a base and TBAB as an additive although the recycle failed. In the case of the Sonogashira-Hagihara reaction, Pd/MWCNTs had to be used as a catalyst and pyrrolidine as a base for the coupling of 4-iodoanisole with phenylacetylene under copper-free conditions. The corresponding 4-methoxytolane was quantitatively obtained allowing the recycling of the catalyst during 3 cycles.The Spanish Ministerios de Ciencia e Innovación (MICINN) and Economía y Competitividad (MINECO) (projects CTQ 2007-62771/BQU, CTQ2010-20387, CTQ2013-43446-P, Consolider Ingenio 2010, CSD2007-00006, CTQ2014-51912-REDC, CTQ2012-31762 and RyC-2009-03813 fellowship), FEDER, the Generalitat Valenciana (PROMETEO 2009/039, PROMETEOII/2014/010, and PROMETEOII/2014/017) and the University of Alicante are gratefully acknowledged for financial support
Pd/zeolite-based catalysts for the preferential CO oxidation reaction: ion-exchange, Si/Al and structure effect
A screening of Pd/zeolite-based catalysts in the PrOx-CO reaction in H2-rich streams was performed using zeolites with different cations (H+, Na+ and Cs+) prepared by ion exchange and framework type (MFI and FAU). The assessment of the catalytic performance displayed by these zeolite-based samples revealed that both parameters play an important role in the catalytic behaviour. The optimisation of both parameters led to the preparation of an optimum catalyst, which showed high CO conversion and CO selectivity during long-term stability tests.The authors thank the Spanish MINECO, GV and FEDER (PROMETEOII/2014/010, Projects CTQ2012-31762), for financial support
Capillary microreactors based on hierarchical SiO2 monoliths incorporating noble metal nanoparticles for the Preferential Oxidation of CO
Novel hierarchical SiO2 monolithic microreactors loaded with either Pd or Pt nanoparticles have been prepared in fused silica capillaries and tested in the Preferential Oxidation of CO (PrOx) reaction. Pd and Pt nanoparticles were prepared by the reduction by solvent method and the support used was a mesoporous SiO2 monolith prepared by a well-established sol–gel methodology. Comparison of the activity with an equivalent powder catalyst indicated that the microreactors show an enhanced catalytic behavior (both in terms of CO conversion and selectivity) due to the superior mass and heat transfer processes that take place inside the microchannel. TOF values at low CO conversions have been found to be ∼2.5 times higher in the microreactors than in the powder catalyst and the residence time seems to have a noticeable influence over the selectivity of the catalysts designed for this reaction. The Pd and Pt flexible microreactors developed in this work have proven to be effective for the CO oxidation reaction both in the presence and absence of H2, standing out as a very interesting and suitable option for the development of CO purification systems of small dimensions for portable and on-board applications.This research was supported financially by MINECO, Generalitat Valenciana and FEDER (Projects CTQ2012-31762 and PROMETEOII/2014/010). J.G.A. and A.B.M. thank the Spanish Ministry of Economy and Competitiveness (MINECO) for their fellowships (BES-2013-063678 and RyC 2009-03913, respectively). I.M.G. and M.N.G. also thank the University of Alicante for their PhD fellowships
One step-synthesis of highly dispersed iron species into silica for propylene epoxidation with dioxygen
Well dispersed iron catalysts were synthesized in silica (Fe0.0XSiO2) by a one-step synthesis procedure. These materials were tested in the propylene epoxidation reaction with gaseous O2. The influence of the iron metal loading on the iron incorporation and distribution in the support (both influenced by the synthetic procedure) were thoroughly studied (conversion, generation and selectivity). Electron Microscopy and UltraViolet–Visible (UV–VIS), Raman and Fourier Transform Infrared Spectroscopy (FTIR) spectroscopy techniques were used to analyze the iron distribution in the catalysts and to probe its incorporation into the silica framework. In situ FTIR was also used to analyze the interaction between propylene and iron-based catalysts. Computational calculations considering a single-site iron catalyst incorporated into the silica structure show a possible interaction between O2 and the incorporated iron atom and the olefin bond and the acidic proton neighboring the iron species which favor the reaction between the two molecules near the iron atom.We thank the MINECO, Generalitat Valenciana and FEDER (Projects CTQ2012-31762, CTQ2015-66080-R and PROMETEOII/2014/010) for financial support. A.B.M. and J.G.A. thank the Spanish Ministry of Economy and Competitiveness (MINECO) for their fellowships (RyC 2009-03913 and BES-2013-063678, respectively)
Diseño de Experimentación en Química Inorgánica sostenible
Se plantea al alumnado el análisis de la huella de carbono que tiene, en la actualidad, la asignatura práctica Experimentación en Química Inorgánica, con el objetivo de que busquen las posibilidades de sustitución y/o reducción de reactivos tóxicos y peligrosos en las prácticas de laboratorio que se imparten. Previamente, en base a dicho análisis, la red ha redactado las directrices que guiarán al alumno en sus búsquedas en bases de datos y su proposición de sustitución razonada de reactivos. Cada grupo de alumnos que trabaja en un proyecto particular de “Síntesis y caracterización de sustancias inorgánicas”, redacta un protocolo de actuación para eliminar/reducir el uso de reactivos peligrosos/contaminantes en su proyecto. Como colofón, se redacta un protocolo global para hacer más sostenible el proceso de enseñanza/aprendizaje de esta asignatura práctica. Además de trabajar el contenido específico de la asignatura, con esta metodología de aprendizaje, se pretende aumentar la capacidad del alumnado del Grado en Química para ser autónomo a la hora de proponer actuaciones fundamentadas que conduzcan a preservar el medio ambiente en su futuro ejercicio de la profesión de graduado en química
BRAF mutations classes I, II, and III in NSCLC patients included in the SLLIP trial : The need for a new pre-clinical treatment rationale
BRAF V600 mutations have been found in 1-2% of non-small-cell lung cancer (NSCLC) patients, with Food and Drug Administration (FDA) approved treatment of dabrafenib plus trametinib and progression free survival (PFS) of 10.9 months. However, 50-80% of BRAF mutations in lung cancer are non-V600, and can be class II, with intermediate to high kinase activity and RAS independence, or class III, with impaired kinase activity, upstream signaling dependence, and consequently, sensitivity to receptor tyrosine kinase (RTK) inhibitors. Plasma cell-free DNA (cfDNA) of 185 newly diagnosed advanced lung adenocarcinoma patients (Spanish Lung Liquid versus Invasive Biopsy Program, SLLIP, NCT03248089) was examined for BRAF and other alterations with a targeted cfDNA next-generation sequencing (NGS) assay (Guardant360®, Guardant Health Inc., CA, USA), and results were correlated with patient outcome. Cell viability with single or combined RAF, MEK, and SHP2 inhibitors was assessed in cell lines with BRAF class I, II, and III mutations. Out of 185 patients, 22 had BRAF alterations (12%) of which seven patients harbored amplifications (32%) and 17 had BRAF mutations (77%). Of the BRAF mutations, four out of 22 (18%) were V600E and 18/22 (82%) were non-V600. In vitro results confirmed sensitivity of class III and resistance of class I and II BRAF mutations, and BRAF wild type cells to SHP2 inhibition. Concomitant MEK or RAF and SHP2 inhibition showed synergistic effects, especially in the class III BRAF-mutant cell line. Our study indicates that the class of the BRAF mutation may have clinical implications and therefore should be defined in the clinical practice and used to guide therapeutic decision
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