Estimation of comprehensive two-dimensional gas chromatographic response from one-dimensional gas chromatography data

Trabajo presentado a la XV Reunión Científica de la Sociedad Española de Cromatografía y Técnicas Afines (SECyTA) celebrada en Castellón de la Plana del 28 al 30 de octubre de 2015Optimization of a separation in comprehensive two-dimensional gas chromatography (GC×GC) requires the selection of an appropriate set column, and the optimisation of their respective dimensions, temperature programs and flow rates. Until not so long ago, a time consuming trial and error process was the only way to select the columns and chromatographic conditions for the two GC dimensions. During the last few years, several attempts have been proposed to estimate the chromatographic response in GC×GC [1-4]. Although most of these methods are helpful contributions, some of them focussed exclusively on the retention time estimation and do not consider the effect of peak width, also essential for a correct prediction of the chromatographic separation capability. Others are based on theoretical formulas not applicable to the extreme experimental conditions used in GC×GC, or are only valid for specific types of compounds or stationary phases: these models cannot be corrected for different separation problems. In this work, modelization of retention time and peak width has been carried out from experimental 1D GC data in order to estimate the response in GC×GC separation for different column sets operated under different flows and temperatures. Several theoretical and experimental models are proposed for estimation of 1D and 2D retention time and peak width; in experimental models, 1D GC data are required together with information on column characteristics and operation conditions. Models for hold-up time, retention factor and peak width were first validated in 1D GC from the fit between experimental and calculated data. Their validation in GC×GC was carried out by using n-alkanes and a mixture of disaccharides as their trimethylsilyl oxime derivatives. Comparison of experimental and estimated data showed good results for retention time in both first and second dimension. Peak widths presented, however, some errors, caused by the no consideration on estimation of the effect of the modulator or the rather unusual chromatographic conditions used. The developed programme is very versatile as it can be used for the calculation of the chromatographic response of compounds with different polarity and volatility, analysed under different pressures and temperature ramps, and with different sets of columns. [1] J.V. Seeley, E.M. Libby, K.A.H. Edwards, S.K. Seeley, J. Chromatogr. A 1216 (2009) 1650. [2] F.L. Dorman, P.D. Schettler, L.A. Vogt, J.W. Cochran, J. Chromatogr. A 1186 (2008) 196. [3] Y. Zhao, J. Zhang, B. Wang, S.H. Kim, A. Fang, B. Bogdanov, Z. Zhou, C. McClain, X. Zhang, J. Chromatogr. A 1218 (2011) 2577. [4] S. Zhu, S. He, D.R. Worton, A.H. Goldstein, J. Chromatogr. A 1233 (2012) 147. Acknowledgements: This work has been funded by Ministerio de Economía y Competitividad (project CTQ2012-32957), Comunidad Autónoma de Madrid (Spain) and European funding from FEDER program (AVANSECAL-CM S2013/ABI-3028) and Fundación Ramón Areces. ACS thanks Ministerio de Economía y Competitividad of Spain for a Ramón y Cajal contract.CTQ2012-32957Peer reviewe

The GRAAL Project

26th International Cosmic Ray Conference Salt Lake City, Utah August 17-25,1999The GRAAL Project (Gamma Ray Astronomy at ALmeria) makes use of the CESA-1 heliostat field at the “Plataforma Solar de Almeria” (Spain) as a gamma-ray telescope with an energy threshold of about 100 GeV. Cherenkov light generated by EAS is reflected by the heliostats and collected into photomultipliers (PMTs) with nonimaging secondary optics. Each PMT collects the light reflected by 13 - 18 heliostats of 40 m2 using a Winston cone. After successful tests with two collecting cones, a more advanced setup on a dedicated platform, using four collectors and 63 heliostats (total reflecting area of about 2500 m2 ) is being installed. A description of this setup together with Monte Carlo results about its excellent capabilities in the precise determination of pulse arrival times are presented

Physiologic Responses to Infrarenal Aortic Cross-Clamping during Laparoscopic or Conventional Vascular Surgery in Experimental Animal Model: Comparative Study

The aim of this study was to compare the hemodynamic and ventilatory effects of prolonged infrarenal aortic cross-clamping in pigs undergoing either laparotomy or laparoscopy. 18 pigs were used for this study. Infrarenal aortic crossclamping was performed for 60 minutes in groups I (laparotomy, n = 6) and II (laparoscopy, n = 6). Group III (laparoscopy, n = 6) underwent a 120-minute long pneumoperitoneum in absence of aortic clamping (sham group). Ventilatory and hemodynamic parameters and renal function were serially determined in all groups. A significant decrease in pH and significant increase in PaCO2 were observed in group II, whereas no changes in these parameters were seen in group I and III. All variables returned to values similar to baseline in groups I and II 60 minutes after declamping. A significant increase in renal resistive index was evidenced during laparoscopy, with significantly higher values seen in Group II. Thus a synergic effect of pneumoperitoneum and aortic cross-clamping was seen in this study. These two factors together cause decreased renal perfusion and acidosis, thus negatively affecting the patient's general state during this type of surgery

Hydrolase–like catalysis and structural resolution of natural products by a metal–organic framework

The exact chemical structure of non–crystallising natural products is still one of the main challenges in Natural Sciences. Despite tremendous advances in total synthesis, the absolute structural determination of a myriad of natural products with very sensitive chemical functionalities remains undone. Here, we show that a metal–organic framework (MOF) with alcohol–containing arms and adsorbed water, enables selective hydrolysis of glycosyl bonds, supramolecular order with the so–formed chiral fragments and absolute determination of the organic structure by single–crystal X–ray crystallography in a single operation. This combined strategy based on a biomimetic, cheap, robust and multigram available solid catalyst opens the door to determine the absolute configuration of ketal compounds regardless degradation sensitiveness, and also to design extremely–mild metal–free solid–catalysed processes without formal acid protons.This work was supported by the Ministero dell’Istruzione, dell’Università e della Ricerca (Italy) and the MINECO (Spain) (Projects CTQ2016-75671-P, CTQ 2017-86735-P, RTC-2017-6331-5, Severo Ochoa program SEV-2016-0683 and Excellence Unit “Maria de Maeztu” MDM-2015-0538). R.B. thanks the MIUR (Project PON R&I FSE-FESR 2014–2020) for grant. L.B wishes to thank Italian MIUR for grant n. AIM1899391–1 in the framework of the project “Azione I.2, Mobilità dei Ricercatori, PON R&I 2014–2020”. Thanks are also extended to the “2019 Post-doctoral Junior Leader-Retaining Fellowship, la Caixa Foundation (ID100010434 and fellowship code LCF/BQ/PR19/11700011” (J. F.- S.). S. S.-N. thanks ITQ for the concession of a contract. D.A. acknowledges the financial support of the Fondazione CARIPLO/“Economia Circolare: ricerca per un futuro sostenibile” 2019, Project code: 2019–2090, MOCA. E.P. acknowledges the financial support of the European Research Council under the European Union’s Horizon 2020 research and innovation program/ERC Grant Agreement No. 814804, MOF-reactors

Red de seguimiento del grado en Geología (Facultad de Ciencias, UA)

Con el comienzo del cuarto y último curso del grado en Geología en el año académico 2013-14 y en el marco del programa de Redes de Investigación en Docencia Universitaria de la Universidad de Alicante, en la Facultad de Ciencias se ha constituido una red de trabajo formada por los profesores coordinadores de semestre del Grado en Geología, que tiene como principal objetivo favorecer, tanto el buen funcionamiento del título, como la gestión interna del seguimiento del mismo. Se persigue pues detectar posibles deficiencias en la implementación del título, proponiendo recomendaciones y sugerencias de mejora, así como evidenciar los progresos del título en el desarrollo del Sistema de Garantía Interno de Calidad (SGIC), tanto en lo relativo a la revisión de la aplicación del plan de estudios, como a la propuesta de acciones para mejorar su diseño e implantación. El método de trabajo se ha basado en reuniones en las que los miembros de la red han planteado y debatido los parámetros e indicadores de seguimiento de la red

Degradation of Penicillinic Antibiotics and β-Lactamase Enzymatic Catalysis in a Biomimetic Zn-Based Metal–Organic Framework

β-Lactam antibiotics are one of the most commonly prescribed drugs to treat bacterial infections. However, their use has been somehow limited given the emergence of bacteria with resistance mechanisms, such as β-lactamases, which inactivate them by degrading their four-membered β-lactam rings. So, a total knowledge of the mechanisms governing the catalytic activity of β-lactamases is required. Here, we report a novel Zn-based metal–organic framework (MOF, 1), possessing functional channels capable to accommodate and interact with antibiotics, which catalyze the selective hydrolysis of the penicillinic antibiotics amoxicillin and ceftriaxone. In particular, MOF 1 degrades, very efficiently, the four-membered β-lactam ring of amoxicillin, acting as a β-lactamase mimic, and expands the very limited number of MOFs capable to mimic catalytic enzymatic processes. Combined single-crystal X-ray diffraction (SCXRD) studies and density functional (DFT) calculations offer unique snapshots on the host-guest interactions established between amoxicillin and the functional channels of 1. This allows to propose a degradation mechanism based on the activation of a water molecule, promoted by a Zn-bridging hydroxyl group, concertedly to the nucleophilic attack to the carbonyl moiety and the cleaving of C−N bond of the lactam ring.This work was supported by the MICINN (Spain) (Projects PID2019-104778GB-I00, PID2020-115100GB-I00, and Excellence Units “Severo Ochoa” CEX2021-001230-S and “Maria de Maeztu” CEX2019-000919-M) and the Ministero dell'Istruzione, dell'Università e della Ricerca (Italy). The work has also been funded by Generalitat Valenciana, Prometeo Grupos de Investigación de Excelencia (PROMETEU/2021/054). D.A. also acknowledges the financial support of the European Union - NextGenerationEU under the National Recovery and Resilience Plan (NRRP) of Ministero dell'Università e della Ricerca (MUR) (Project code PE0000021, “Network 4 Energy Sustainable Transition - NEST). Thanks are also extended to the 2019 Post-doctoral Junior Leader-Retaining Fellowship, la Caixa Foundation (ID100010434 and fellowship code LCF/BQ/PR19/11700011), the “Generalitat Valenciana” (SEJI/2020/034) and the “Ramón y Cajal” program (J.F.-S.). E.P. acknowledges the financial support of the European Research Council under the European Union's Horizon 2020 research and innovation programme / ERC Grant Agreement No 814804, MOF-reactors. S.S.-N. thanks a fellowship from MINECO (project number CTQ 2017–86735-P). This study forms part of the Advanced Materials programme (MFA/2022/048) and was supported by MCIN with funding from European Union NextGenerationEU (PRTR-C17.I1) and by Generalitat Valenciana. Financial support from Dipartimento di Chimica e Tecnologie Chimiche (CTC), Università della Calabria, is also gratefully acknowledged for computational investigation

Grado en Geología de la Universidad de Alicante (2010-2014). Red de seguimiento

Con el comienzo del cuarto y último curso del grado en Geología en 2013-14, en la Facultad de Ciencias de la Universidad de Alicante se constituyó una red de seguimiento formada por todos los profesores coordinadores de semestre del citado grado. Esta red se enmarca en el programa de Redes de Investigación en Docencia Universitaria que la Universidad de Alicante ha implementado desde la implantación de los títulos de grado. El objetivo principal de esta red docente se ha centrado en realizar un seguimiento de la titulación en el marco de Sistema de Garantía Interno de Calidad (SGIC) y en desarrollar herramientas que favorezcan, tanto el buen funcionamiento del título, como la gestión interna del seguimiento del mismo. El método de trabajo se ha basado en reuniones en las que los miembros de la red han planteado y debatido los parámetros e indicadores de seguimiento de la red. Esta red ha trabajado conjuntamente con otras comisiones de la titulación como la Comisión del Grado en Geología (CGG), la Comisión de Trabajo de Fin de Grado en Geología (CTFGG) o la Comisión de Garantía de Calidad de la Facultad de Ciencias (CGCFC)

Soluble/MOF-Supported Palladium Single Atoms Catalyze the Ligand-, Additive-, and Solvent-Free Aerobic Oxidation of Benzyl Alcohols to Benzoic Acids

Metal single-atom catalysts (SACs) promise great rewards in terms of metal atom efficiency. However, the requirement of particular conditions and supports for their synthesis, together with the need of solvents and additives for catalytic implementation, often precludes their use under industrially viable conditions. Here, we show that palladium single atoms are spontaneously formed after dissolving tiny amounts of palladium salts in neat benzyl alcohols, to catalyze their direct aerobic oxidation to benzoic acids without ligands, additives, or solvents. With this result in hand, the gram-scale preparation and stabilization of Pd SACs within the functional channels of a novel methyl-cysteine-based metal-organic framework (MOF) was accomplished, to give a robust and crystalline solid catalyst fully characterized with the help of single-crystal X-ray diffraction (SCXRD). These results illustrate the advantages of metal speciation in ligand-free homogeneous organic reactions and the translation into solid catalysts for potential industrial implementation.This work was supported by the Ministero dell’Istruzione, dell’Università e della Ricerca (Italy) and the MINECO (Spain) (Projects PID2019−104778GB−I00, CTQ 2017–86735–P, RTC–2017–6331–5, Severo Ochoa program SEV–2016–0683 and Excellence Unit “Maria de Maeztu” CEX2019−000919−M). E.T. and M.M. thank MINECO and ITQ for the concession of a contract. D.A. acknowledges the financial support of the Fondazione CARIPLO/“Economia Circolare: ricerca per un futuro sostenibile” 2019, Project code: 2019–2090, MOCA and Diamond Light Source for awarded beamtime and provision of synchrotron radiation facilities and thanks Dr. Sarah Barnett and David Allan for their assistance at I19 beamline (Proposal No. MT18768-1). Thanks are also extended to the “2019 Post-doctoral Junior Leader-Retaining Fellowship, la Caixa Foundation (ID100010434 and fellowship code LCF/BQ/PR19/11700011” (J.F.-S.) and “La Caixa” scholarship (ID 100010434) LCF/BQ/DI19/11730029 (J.B.-S). E.P. acknowledges the financial support of the European Research Council under the European Union’s Horizon 2020 research and innovation programme/ERC Grant Agreement No 814804, MOF reactors. J.O.-M. acknowledges the Juan de la Cierva program for the concession of a contract (IJC2018-036514-I). We gratefully acknowledge to ALBA synchrotron for allocating beamtime and CLÆSS beamline staff for their technical support during our experiment. The computations were performed on the Tirant III cluster of the Servei d’Informàtica of the University of Valencia.Peer reviewe