Search results for "frameworks"
showing 10 items of 120 documents
Exploring chemical complexity in group IV reticular solids
2022
Esta tesis aborda el reto de ampliar las herramientas sintéticas disponibles para aumentar la complejidad química de los materiales reticulares basados en metales del grupo IV, dirigiéndose tanto a la parte orgánica como a la inorgánica de estos materiales porosos e híbridos. El capítulo 1 ofrece una visión del aumento de la complejidad química en los sólidos reticulares, que proporciona un contexto general a los resultados desarrollados durante esta tesis. A continuación, la introducción de la variación química en los conectores orgánicos se describe en los capítulos 2, 3 y 4, mientras que la transformación química de los nodos inorgánicos se introduce en el capítulo 5. Todo el trabajo des…
Risku vadība Zviedrijas bankās
2021
Paaugstināta tirgus nepastāvība, finanšu krīzes un ekonomikas lejupslīde radīja risku pārvaldības ideju kā vienu no visvairāk pieaugošajām bažām banku nozarē. Pēdējās desmitgadēs, īpaši pēc 2008. Gada finanšu krīzes, riska pārvaldības jēdziens ir piedzīvojis transformācijas pārmaiņas. Šīs tēzes mērķis ir uztvert pašreizējo riska pārvaldības scenāriju bankās, kas darbojas Zviedrijas tirgū. Darbs sākas ar vēsturiskā un mūsdienu riska jēdziena analīzi, kam seko riska pārvaldības jēdziena novērtējums un tā piemērošana banku un finanšu iestādēs. Lai koncepcija būtu precīza un saprotama, ir apspriesta arī dažāda riska pārvaldības prakse un ietvars. Pētījums tika veikts, lai apgaismotu dažādus pri…
Cyanido-Bridged FeII-MI Dimetallic Hofmann-Like Spin-Crossover Coordination Polymers Based on 2,6-Naphthyridine
2017
[EN] Two new 3D spin-crossover (SCO) Hofmann-type coordination polymers {Fe(2,6-naphthy)[Ag(CN)2][Ag2(CN)3]} (1; 2,6-naphthy = 2,6-naphthyridine) and {Fe(2,6-naphthy)- [Au(CN)2]2}·0.5PhNO2 (2) were synthesized and characterized. Both derivatives are made up of infinite stacks of {Fe[Ag(CN)2]2- [Ag2(CN)3]}n and {Fe[Au(CN)2]2}n layered grids connected by pillars of 2,6-naphthy ligands coordinated to the axial positions of the FeII centers of alternate layers.
Solvent-free synthesis of ZIFs: a route toward the elusive Fe(II) analogue of ZIF-8
2019
Herein we report the synthesis of an elusive metal-organic framework, the iron(II) analogue of ZIF-8 with the formula Fe(2-methylimidazolate) , here denoted as MUV-3. The preparation of this highly interesting porous material, inaccessible by common synthetic procedures, occurs in a solvent-free reaction upon addition of an easily detachable template molecule, yielding single crystals of MUV-3. This methodology can be extended to other metals and imidazolate derivatives, allowing the preparation of ZIF-8, ZIF-67, and the unprecedented iron(II) ZIFs Fe(2-ethylimidazolate) and Fe(2-methylbenzimidazolate) . The different performance of MUV-3 toward NO sorption, in comparison to ZIF-8, results …
Blaming the Light, Claiming the Night. Actors, Issues and Effects of Lighting Conflicts in France since the 1980's
2014
International audience; Regarding environmental issues, conflictuality is a privileged way to reach the political arena. "Naming, Blaming, Claiming": three steps that make the controversy emerge, constitute the public issue, then bring it to the politi- cal agenda. These three stages are clearly identifiable in the history of night protection associative movements. These movements emerged in the 1970's in the United States of America, quickly disseminated enjoying a broader context of environmental thinking. Conflicts related to artificial lighting are structurally akin to conflicts of contradictory uses of a single resource: the night. For some - the technicists -, the night is the "good-s…
Photodegradation of Brilliant Green Dye by a Zinc bioMOF and Crystallographic Visualization of Resulting CO2
2021
We present a novel bio-friendly water-stable Zn-based MOF (1), derived from the natural amino acid L-serine, which was able to efficiently photodegrade water solutions of brilliant green dye in only 120 min. The total degradation was followed by UV-Vis spectroscopy and further confirmed by single-crystal X-ray crystallography, revealing the presence of CO2 within its channels. Reusability studies further demonstrate the structural and performance robustness of 1.
New Microbe Killers : Self-Assembled Silver(I) Coordination Polymers Driven by a Cagelike Aminophosphine
2019
New Ag(I) coordination polymers, formulated as [Ag(μ-PTAH)(NO3)2]n (1) and [Ag(μ-PTA)(NO2)]n (2), were self-assembled as light- and air-stable microcrystalline solids and fully characterized by NMR and IR spectroscopy, electrospray ionization mass spectrometry (ESI-MS(±), elemental analysis, powder (PXRD) and single-crystal X-ray diffraction. Their crystal structures reveal resembling 1D metal-ligand chains that are driven by the 1,3,5-triaza-7-phospaadamantane (PTA) linkers and supported by terminal nitrate or nitrite ligands; these chains were classified within a 2C1 topological type. Additionally, the structure of 1 features a 1D!2D network extension through intermolecular hydrogen bonds…
Exploiting the Redox Activity of MIL-100(Fe) Carrier Enables Prolonged Carvacrol Antimicrobial Activity
2022
The design of efficient food contact materials that maintain optimal levels of food safety is of paramount relevance to reduce the increasing number of foodborne illnesses. In this work, we develop a smart composite metal-organic framework (MOF)-based material that fosters a unique prolonged antibacterial activity. The composite is obtained by entrapping a natural food preserving molecule, carvacrol, into a mesoporous MIL-100(Fe) material following a direct and biocompatible impregnation method, and obtaining particularly high payloads. By exploiting the intrinsic redox nature of the MIL-100(Fe) material, it is possible to achieve a prolonged activity against Escherichia coli and Listeria i…
Reticular Metal-Organic Frameworks for sustainable applications
2023
La presente tesis doctoral se ha realizado mediante compendio de publicaciones en cumplimiento con las normativas establecidas por la Universidad de Valencia, según lo dispuesto en el reglamento ACGUV 266/2011 referente al depósito, evaluación y defensa de tesis doctorales, con la última actualización correspondiente al 31 de Octubre de 2017. El trabajo se encuentra estructurado en tres capitulos principales, seguidos de un capítulo final que engloba las conclusiones obtenidas a partir de los resultados de la investigación, así como los planes y perspectivas para trabajos futuros. El capitulo 1 proporciona un contexto general sobre los materiales abordados en esta tesis: Metal-Organ…
Cooperative High-Temperature Spin Crossover Accompanied by a Highly Anisotropic Structural Distortion
2016
Spin transitions are a spectacular example of molecular switching that can provoke extreme electronic and structural reorganizations in coordination compounds. A new 3D cyanoheterometallic framework, [Fe(pz)(Au(CN)2)2], has been synthesized in which a highly cooperative spin crossover has been observed at 367 and 349 K in heating and cooling modes, respectively. Mössbauer spectroscopy revealed a complete transition between the diamagnetic and paramagnetic states of the iron centres. The low-spin-to-high-spin transition induced a drastic structural distortion involving a large one-directional expansion (ca. 10.6%) and contraction (ca. 9.6%) of the lattice. Negative thermal expansion along th…