Coordination polymer particles with ligand-centred pH-responses and spin transition

A bis-catechol ligand connected through an imine bond is used to fabricate switchable coordination polymer particles with pH-tuned spin transition responses.This work was supported by the project MAT2012-38318-C03-02 from the Spanish Government and FEDER funds. F. N. thanks Universidad Nacional del Sur for supporting her postdoctoral stay. F. N. thanks the Ministerio de Ciencia e Innovación (MICINN) for a postdoctoral JdC fellowship. The authors also thank ECOSTBio Cost Action.Peer Reviewe

Análisis de tecnología para la implementación de arquitecturas de procesamiento de grandes datos

En la actualidad, el desarrollo del ancho de banda en los sistemas de comunicaciones y el aumento de la capacidad de los dispositivos de almacenamiento, ha dado lugar a que los volúmenes de información disponible para ser tratada hayan crecido enormemente, dando lugar a los Grandes Datos o Big Data. Pese a que los procesadores de ordenadores personales y servidores también han visto incrementada su potencia sustancialmente, se hace necesario un nuevo modo de tratar con toda esta información. El objetivo de este Proyecto Fin de Carrera es evaluar las capacidades de una herramienta para el tratamiento de Grandes Datos para su implementación en una red de comunicaciones existente teniendo en cuenta sus características, necesidades y restricciones particulares. El tamaño de la red de comunicaciones y la diversidad de fuentes de información presentes en la misma hacen imposible la implementación completa de la solución necesaria para resolver el problema. Por este motivo se optó por implementar una arquitectura genérica más reducida y alimentarla con fuentes de datos específicas de esta red de comunicaciones concreta en lugar de otras estándar. Con este montaje se realizaron pruebas de evaluación y validación de la herramienta que permitieron concluir su idoneidad para el caso objeto de estudio. Aunque se deja para trabajo futuro la implementación práctica de la herramienta de Grandes Datos y su integración en la red de comunicaciones, se ha realizado un análisis de las características de todas las fuentes de información presentes en la misma, así como naturaleza de la información proveniente de cada una de ellas. También se propone una arquitectura completa capaz de prestar el servicio.Nowadays, bandwidth increase in communications systems and capacity enhancement in storage devices has resulted in a huge growth in volume of information available for processing, which is known as Big Data. Even though processors in personal computers and enterprise servers have seen their performance substantially improve as well, a new way to deal with all this information has become necessary. The goal for this Final Degree Project is to evaluate capacities for a Big Data management tool, in order to implement it on an existing communications network, taking into consideration its particular characteristics, needs and restrictions. Size of the communications network and variety of all its sources of information make it impossible to implement the full system that would be necessary to tackle the problem. For this reason, it was decided to implement a generic setup, smaller and feed it with sources of data specific to this communications network, instead of any other standard ones. Evaluation and validation test were undergone on this setup, and let us conclude it was suitable for the specific scenario. Even though practical implementation of this Big Data management tool and its integration into the communications network has been postponed for future work, all sources of information present on it have been analyzed, and so has the nature of information generated by each of them. A full architecture, capable of delivering the service has also been proposed.Ingeniería de Telecomunicació

Recent advances in porous nanoparticles for drug delivery in antitumoral applications: inorganic nanoparticles and nanoscale metal-organic frameworks

Introduction: Nanotechnology has provided new tools for addressing unmet clinical situations, especially in the oncology field. The development of smart nanocarriers able to deliver chemotherapeutic agents specifically to the diseased cells and to release them in a controlled way has offered a paramount advantage over conventional therapy. Areas covered: Among the different types of nanoparticle that can be employed for this purpose, inorganic porous materials have received significant attention in the last decade due to their unique properties such as high loading capacity, chemical and physical robustness, low toxicity and easy and cheap production in the laboratory. This review discuss the recent advances performed in the application of porous inorganic and metal-organic materials for antitumoral therapy, paying special attention to the application of mesoporous silica, porous silicon and metal-organic nanoparticles. Expert opinion: The use of porous inorganic nanoparticles as drug carriers for cancer therapy has the potential to improve the life expectancy of the patients affected by this disease. However, much work is needed to overcome their drawbacks, which are aggravated by their hard nature, exploiting the advantages offered by highly the ordered pore network of these materials

Covalent Grafting of Coordination Polymers on Surfaces: The Case of Hybrid Valence Tautomeric Interphases

© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. We have developed a novel approach for grafting coordination polymers, structured as nanoparticles bearing surface reactive carboxylic groups, to amino-functionalized surfaces through a simple carbodiimide-mediated coupling reaction. As a proof-of-concept to validate our approach, and on the quest for novel hybrid interphases with potential technological applications, we have used valence tautomeric nanoparticles exhibiting spin transition at or around room temperature. SEM and AFM characterization reveal that the nanoparticles were organized chiefly into a single monolayer while X-ray photoelectron spectroscopy (XPS) measurements confirm that the nanoparticles retain a temperature-induced electronic redistribution upon surface anchorage. Our results represent an effective approach towards the challenging manufacture of coordination polymers. CPPs immobilization: A generic approach for immobilizing coordination polymer nanoparticles (CPPs) on gold surfaces is reported. The protocol involves covalent bonding between amino-terminated alkyl chains on the gold surface and carboxylic groups on the CPPs surface. The thickness of the nanoparticle monolayer is comparable to the nanoparticle size. The nanoparticles used exhibit valence tautomerism in bulk and keep this property after surface attachment, as corroborated by X-ray photoelectron spectroscopy (XPS) measurements. The results represent an effective approach towards the manufacture of coordination polymers.F. N. thanks the Ministerio de Ciencia e Innovación (MICINN) for a postdoctoral JdC fellowship. This work was supported by project MAT2012-38318-C03-02 from the Spanish Government and by FEDER funds. ICN2 acknowledges support from the Severo Ochoa Program (MINECO, Grant SEV-2013-0295). The authors also thank MP1202 Cost ActionPeer Reviewe

Design and synthesis of a noninnocent multitopic catechol and pyridine mixed ligand: Nanoscale polymers and valence tautomerism

The design and synthesis of a new redox-active ligand combining catechol and pyridine units have allowed the achievement of cobalt-based nanoscale coordination polymer particles in a single-step exhibiting a switchable valence tautomeric behavior and thermal hysteresis. The combination of polymerizing capabilities with redox-active responses in a unique ligand leads to the formation of nanoparticles exhibiting a gradual valence tautomeric interconversion in the 35-370 K temperature range. Using one single ligand to obtain these nanoparticles facilitates possible nanostructure formation methodologies.This work was supported ICN2 acknowledges support from the Severo Ochoa Program (MINECO, Grant SEV-2013-0295). F.N. thanks the Ministerio de Ciencia e Innovación (MICINN) for a JdC fellowship. M.G. thanks the Consejo Superior de Investigaciones Cientifícas (CSIC) for a JAE fellowship.Peer Reviewe

Coordination polymers built from 1,4-bis(imidazol-1-ylmethyl)benzene : from crystalline to amorphous

The supramolecular chemistry of the bis-imidazole ligand 1,4-bis(imidazol-1-ylmethyl)benzene, popularly known as bix, has been explored by various researchers in order to synthesize functional coordination polymers (CPs). The flexibility of the bix ligand, its unpredictable conformation and its coordination behaviour with transition metal ions have resulted in a huge number of structurally diverse and functionally intriguing CPs. In this perspective review we discuss the progress in CPs of bix between 1997 and today. More precisely, this review emphasizes the developments in functional supramolecular coordination polymers built from the bix ligand, from crystalline materials to amorphous nanomaterials

Surface-confined molecular coolers for cryogenics

An excellent molecule-based cryogenic magnetic refrigerant, gadolinium acetate tetrahydrate, is here used to decorate selected portions of silicon substrate. By quantitative magnetic force microscopy for variable applied magnetic field near liquid-helium temperature, we demonstrate that the molecules hold intact their magnetic properties, and therefore their cooling functionality, after their deposition. Our result represents a step forward towards the realization of a molecule-based microrefrigerating device for very low temperatures.Comment: 16 pages, 4+1 figures, S.I. available from author

Synthesis of polydopamine at the femtoliter scale and confined fabrication of Ag nanoparticles on surfaces

Nanoscale polydopamine motives are fabricated on surfaces by deposition of precursor femtolitre droplets with an AFM tip and used as confined reactors to fabricate Ag nanoparticles patterns by in-situ reduction of an Ag+ salt

Water-Stable Upconverting Coordination Polymer Nanoparticles for Transparent Films and Anticounterfeiting Patterns with Air-Stable Upconversion

Altres ajuts: acords transformatius de la UABPhoton upconversion (UC) based on triplet-triplet annihilation is a very promising phenomenon with potential application in several areas, though, due to the intrinsic mechanism, the achievement of diffusion-limited solid materials with air-stable UC is still a challenge. Herein, we report UC coordination polymer nanoparticles (CPNs) combining sensitizer and emitter molecules especially designed with alkyl spacers that promote the amorphous character. Beyond the characteristic constraints of crystalline MOFs, amorphous CPNs facilitate high dye density and flexible ratio tunability. To show the universality of the approach, two types of UC-CPNs are reported, exhibiting highly photostable UC in two different visible spectral regions. Given their nanoscale, narrow size distribution, and good chemical/colloidal stability in water, the CPNs were also successfully printed as anticounterfeiting patterns and used to make highly transparent and photostable films for luminescent solar concentrators, both showing air-stable UC

Experimental Study of Two Air Management Strategies for Emissions Control in Heavy Duty Engines at Medium to High Loads

"This document is the Accepted Manuscript version of a Published Work that appeared in final form in Energy & Fuels, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://pubs.acs.org/page/policy/articlesonrequest/index.html"[EN] Different air management strategies, Miller timing and internal EGR (iEGR), have been studied on internal combustion engines with the objective of decreasing NOx emissions. This paper explores heavy duty diesel engine performance by the application of both strategies separately through two different camshaft configurations, mounted and tested in the same engine. On one side, in the case of Miller timing, the early intake valve closing is explored, and on other side, for iEGR, the study is carried out opening the exhaust valve during the intake process. The engine emission and performance study is achieved through the application of a methodology which begins with the selection of the operating points focusing on medium to high loads. It continues with the exploration of different camshaft profiles by mean of a 1D model. Through the 1D model, two camshaft profiles are selected and tested in the test cell, determining the intake valve closing conditions followed by the identification of the thermodynamic behavior during the compression stroke before the injection. Later on, the combustion and emissions formation analysis is performed to conclude with the fuel consumption study for each implemented strategy taking into consideration the important influence of each camshaft profile in the pumping loop. A short discussion on the transient performance effect of each air management strategy completes the scope of the study.Daniel Estepa is partially supported through contract FPI-S2-2015-1091 of Programa de Apoyo para la Investigacion y Desarrollo (PAID) of Universitat Politecnica de Valencia.Bermúdez, V.; Molina, S.; Novella Rosa, R.; Estepa-Ruiz, D. (2017). Experimental Study of Two Air Management Strategies for Emissions Control in Heavy Duty Engines at Medium to High Loads. Energy & Fuels. 31(9):10011-10022. https://doi.org/10.1021/acs.energyfuels.7b00945S100111002231