A5102900239- Molecular Junctions and Nanostructures
- Metal-Organic Frameworks: Synthesis and Applications
- Semiconductor materials and devices
- Catalysis for Biomass Conversion
- Supramolecular Chemistry and Complexes
- Layered Double Hydroxides Synthesis and Applications
- Photochemistry and Electron Transfer Studies
- Electronic and Structural Properties of Oxides
- Postharvest Quality and Shelf Life Management
- Nanocomposite Films for Food Packaging
- Advanced Chemical Physics Studies
- Innovations in Concrete and Construction Materials
- Nanopore and Nanochannel Transport Studies
- Additive Manufacturing and 3D Printing Technologies
- Microplastics and Plastic Pollution
- Recycling and Waste Management Techniques
- Occupational Health and Safety in Workplaces
- Advanced Photocatalysis Techniques
- Spectroscopy and Quantum Chemical Studies
- Surface Chemistry and Catalysis
- Nanomaterials for catalytic reactions
- Knowledge Societies in the 21st Century
- Mass Spectrometry Techniques and Applications
- Magnesium Oxide Properties and Applications
- Analytical chemistry methods development
Consejo Nacional de Investigaciones Científicas y Técnicas
2002-2023
National Technological University
2015-2023
National University of Río Negro
2022-2023
Universidad Nacional de Colombia
2020-2021
University of Groningen
2005-2008
National University of the Littoral
2003-2008
University of Amsterdam
2008
University of Edinburgh
2006-2008
Instituto de Desarrollo Tecnológico para la Industria Química
2003-2008
CEA LITEN
2006
Although the desirability of developing synthetic molecular machine systems that can function on surfaces is widely recognized, to date only well-characterized examples electrochemically switchable rotaxane-based shuttles which do so are based tetracationic viologen macrocycle pioneered by Stoddart. Here, we report a [2]rotaxane features succinamide and naphthalene diimide hydrogen-bonding stations for benzylic amide shuttle switch its net position both in solution monolayer. Three oxidation...
We report a study of acid-terminated self-assembled monolayers alkanethiols different length, 11-mercaptoundecanoic acid (11-MUA) and 16-mercaptohexadecanoic (16-MHDA), on Au(111). Scanning tunneling microscopy (STM), X-ray photoelectron spectroscopy (XPS), cyclic voltammetry (CV), electrochemical impedance (EIS), contact angle techniques were used for characterization, the results compared with those obtained from n-alkanethiols similar chain providing detailed description two-dimensional...
At present, the trend towards partial replacement of petroleum-derived fuels by those from revaluation biomass has become great importance. An effective strategy for processing complex feedstocks involves prior conversion to simpler compounds (platform molecules) that are more easily transformed in subsequent reactions. This study analyzes metal–organic frameworks (MOFs) contain Zr metal clusters formed ligands terephthalic acid (UiO-66) and aminoterephthalic (UiO-66-NH2), as active stable...
ADVERTISEMENT RETURN TO ISSUEPREVNoteNEXTImproved Synthesis of CavitandsEsteban Román, Carlos Peinador, Sandra Mendoza, and Angel E. KaiferView Author Information Center for Supramolecular Science Chemistry Department, University Miami, Coral Gables, Florida 33124-0431 Cite this: J. Org. Chem. 1999, 64, 7, 2577–2578Publication Date (Web):March 18, 1999Publication History Received5 November 1998Revised25 January 1999Published online18 March inissue 1 April...
The boron removal capacity from an aqueous solution using MgAlFe mixed oxides layered double hydroxides (LDH) was studied. They were synthesized by the coprecipitation method at 70 °C and characterized as potential filter materials. Fe3+ analyzed X-ray photoelectron spectroscopy UV–visible diffuse reflectance showed their tetrahedral octahedral coordination. Scanning electron microscopy micrographs thermogravimetric differential scanning calorimetry analysis evidenced presence of clusters...
We report on measurements of electron emission spectra from surfaces highly oriented pyrolytic graphite (HOPG) excited by 1-5 keV He+ and Li+ which, for He+, exhibit a previously unreported high-energy structure. Through full quantum dynamic description that allows the calculation neutralization electron-hole pair excitation, we show these electrons can arise autoionization excitons formed promotion to conduction band states close vacuum level. The same explains observed absence HOPG.
Thin films of fumaramide [2]rotaxane, a mechanically interlocked molecule composed macrocycle and thread in "bead thread" configuration, were prepared by vapor deposition on both Ag(111) Au(111) substrates. X-ray photoelectron spectroscopy (XPS) high-resolution electron-energy-loss used to characterize monolayer bulklike multilayer films. XPS determination the relative amounts carbon, nitrogen, oxygen indicates that adsorbs intact. On metal surfaces, molecules first adsorbed layer show an...
Dithienylethene-based molecular switches have been extensively studied in solution and are considered excellent candidates the design of molecular-based electronic devices. However, for most foreseeable applications they to be integrated solid state, namely as building blocks bottom-up approaches prepare functional addressable surfaces. Here we present a study structure chemical nature dithienylethene switch thin films on Au(111) by X-ray photoemission spectroscopy, which proves powerful...
In the field of biomass valorization, use levulinic acid, a platform molecule to obtain products with higher-added value, has attracted research interest in recent years. Therefore, present work proposes synthesis esters by means catalytic esterification acid methanol, ethanol, and butanol. For this purpose, metal–organic framework UiO-66-NH2 catalysts have been synthesized, zirconium as active metal, 2-aminoterephthalic binding agent, dimethylformamide solvent. addition, an alternative...
The massive use of petroleum and its possible exhaustion are driving the current research trend to study alternative raw materials from biomass for organic reactions. In this context, present article presents a catalytic esterification levulinic acid, platform molecule, with ethanol. Metal-organic framework (MOF) type compounds UiO-66-NH2 have been synthesized. Zirconium was incorporated, using zirconium chloride as metal precursor, together 2-aminoterephthalic acid an binding agent. An...
Surface enhanced second harmonic generation (SE SHG) experiments on molecular structures, macrocycles, catenanes, and rotaxanes, deposited as monolayers multilayers by vacuum sublimation silver, are reported. The measurements show that the molecules form ordered thin films, where highest degree of order is observed in case macrocycle lowest rotaxane multilayers. activity interpreted terms electric field induced (EFISH) created substrate silver atoms. measured nonlinear optical susceptibility...
Abstract In this study cut, pineapple slices of 1 cm thick were packaged and stored at different temperatures equilibrium modified atmosphere packages (EMAPs) to determine changes color firmness over time represent physicochemical shelf life. From the experimental data, a variance analysis was performed effect temperature O 2 level on evolution (CIELAB coordinates) firmness. It observed that in L * , b coordinates is independent concentration EMAP system. After that, suitable models adjusted...
Abstract Ultrasonic logging has been used extensively in Colombia, the Andesfoothills, to quantitatively evaluate casing wear and deformation. Casingstrings can be lost buckling, shearing excessive wear. Activestresses applied strings from active movement of faultscontribute degradation integrity strength. These deformations are very costly often cause well bore beabandoned or re-drilled. Imaging planar view, 2D cross-sectionand 3D perspective view helpful better understand thedeformation...
RESUMEN El procedimiento de Modelación por Deposición Filamento (MDF) polimérico es una las variantes mayor repercusión en el conjunto tecnologías construcción aditiva, usualmente llamadas impresión 3D. La irrupción máquinas bajo costo y la continua mejora calidad resistencia los polímeros empleados, exige estimar vida útil performance piezas impresas. Por ello, este trabajo analiza desempeño mecánico ante esfuerzos flexión que típicamente se emplean aditiva. En particular evalúa, a través...