28 research outputs found

    DMSO as solvent on the synthesis of flame-retardant polyether polyols

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    Polyether polyols with flame-retardant properties are synthesized by using glycerol phosphate disodium salt as an initiator and dimethyl sulfoxide (DMSO) as a solvent. The molecular weight of the polyol decreased when higher solvent to initiator ratios were used, revealing that a larger amount of salt was activated. In addition, the larger the amount of activated salt was, the higher the percentage of phosphorous was in the final polyol. Glycerol phosphate disodium salt was still partially insoluble in the studied proportions of DMSO. Thus, the recovery and reuse of this part of the salt for the synthesis of new flame-retardant polyols were evaluated. The recovered salt promoted a shorter induction period because it presented a larger amount of deprotonated hydroxyl groups. In addition, there were no differences between both synthesized polyols, indicating that it is possible to use the recovered salt in the same way as it is used commercially with the advantage of a shorter induction period for polymerization.Se sintetizan polioles de poliéter con propiedades ignífugas utilizando fosfato de glicerol como iniciador y dimetilsulfóxido (DMSO) como disolvente. El peso molecular del poliol disminuyó cuando se utilizaron mayores proporciones de disolvente e iniciador, lo que revela que se activó una mayor cantidad de sal. cantidad de sal fue activada. Además, cuanto mayor era la cantidad de sal activada, mayor era el porcentaje de fósforo. el porcentaje de fósforo en el poliol final. La sal disódica de fosfato de glicerol seguía siendo parcialmente insoluble en las proporciones estudiadas de DMSO. Así, la recuperación y reutilización de esta parte de la sal para la síntesis de nuevos polioles ignífugos. La sal recuperada promovió un periodo de inducción más corto porque presentaba una mayor cantidad de grupos hidroxilos desprotonados. grupos hidroxilo desprotonados. Además, no hubo diferencias entre ambos polioles sintetizados, lo que indica que es posible utilizar la sal recuperada de la misma manera que se utiliza comercialmente con la ventaja de un periodo de inducción más corto para la polimerización

    Process simulation and economic feasibility assessment of the methanol production via tri-reforming using experimental kinetic equations

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    The purpose of this paper is to assess via techno-economic metrics the feasibility of a tri-reforming coupled methanol process. The simulation of the tri-reforming reactor considered empiric kinetic equations, developed by our group in previous studies. The flue gas coming from the furnace that provides the energy required by the reforming reactor was also used as feed, in order to reduce the CO2 emissions. A sensitivity analysis was carried out to determine the influence of the feed composition and temperature in the tri-reforming process results, studying H2O/CH4 and O2/CH4 ratios (0.5–1.5 and 0.35–0.40, respectively), and varying the temperature between 850 and 1050 °C. The methanol plant was also simulated, and an economical study was carried out to know if the proposed process would be economically feasible. The most relevant economic parameters (including the Net Present Value, the Internal Rate of Return, the Payback Period and the break-even) were calculated, showing a quite robust process from an economical point of view.El propósito de este documento es evaluar a través de métricas tecnoeconómicas la viabilidad de un proceso de metanol acoplado de triple reforma. La simulación del reactor de tri-reformado consideró ecuaciones cinéticas empíricas, desarrolladas por nuestro grupo en estudios previos. También se utilizó como alimentación el gas de combustión procedente del horno que proporciona la energía requerida por el reactor de reformado, con el fin de reducir las emisiones de CO 2 . Se realizó un análisis de sensibilidad para determinar la influencia de la composición y temperatura de la alimentación en los resultados del proceso de tri-reformado, estudiando H 2 O/CH 4 y O 2 /CH 4proporciones (0.5-1.5 y 0.35-0.40, respectivamente), y variando la temperatura entre 850 y 1050 °C. También se simuló la planta de metanol y se realizó un estudio económico para saber si el proceso propuesto sería económicamente factible. Se calcularon los parámetros económicos más relevantes (incluyendo el Valor Presente Neto, la Tasa Interna de Retorno, el Periodo de Recuperación y el punto de equilibrio), mostrando un proceso bastante robusto desde el punto de vista económico

    Energy substrate metabolism, mitochondrial structure and oxidative stress after cardiac ischemia-reperfusion in mice lacking UCP3.

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    Myocardial ischemia-reperfusion (IR) injury may result in cardiomyocyte dysfunction. Mitochondria play a critical role in cardiomyocyte recovery after IR injury. The mitochondrial uncoupling protein 3 (UCP3) has been proposed to reduce mitochondrial reactive oxygen species (ROS) production and to facilitate fatty acid oxidation. As both mechanisms might be protective following IR injury, we investigated functional, mitochondrial structural, and metabolic cardiac remodeling in wild-type mice and in mice lacking UCP3 (UCP3-KO) after IR. Results showed that infarct size in isolated perfused hearts subjected to IR ex vivo was larger in adult and old UCP3-KO mice than in equivalent wild-type mice, and was accompanied by higher levels of creatine kinase in the effluent and by more pronounced mitochondrial structural changes. The greater myocardial damage in UCP3-KO hearts was confirmed in vivo after coronary artery occlusion followed by reperfusion. S1QEL, a suppressor of superoxide generation from site IQ in complex I, limited infarct size in UCP3-KO hearts, pointing to exacerbated superoxide production as a possible cause of the damage. Metabolomics analysis of isolated perfused hearts confirmed the reported accumulation of succinate, xanthine and hypoxanthine during ischemia, and a shift to anaerobic glucose utilization, which all recovered upon reoxygenation. The metabolic response to ischemia and IR was similar in UCP3-KO and wild-type hearts, being lipid and energy metabolism the most affected pathways. Fatty acid oxidation and complex I (but not complex II) activity were equally impaired after IR. Overall, our results indicate that UCP3 deficiency promotes enhanced superoxide generation and mitochondrial structural changes that increase the vulnerability of the myocardium to IR injury.We are grateful to F. S´ anchez-Madrid, B. Iba´nez ˜ and E. Lara for facilitating experiments at CNIC (Madrid, Spain) and to W.E. Louch for facilitating experiments at the University of Oslo (Oslo, Norway). We thank B. Littlejohns, I. Khaliulin and H. Lin from M.S. Suleiman’s group (University of Bristol, Bristol, UK) for their valuable help with Langendorff perfusion experiments. We also thank E.T. Chouchani from M.P. Murphy’s group (Cambridge, UK) for help with metabolomics analysis, M. Guerra of the Electron Microscopy Unit at CBMSO (Madrid, Spain) for processing the samples for electron microscopy analysis, and A.V. Alonso (CNIC) for echocardiography analyses. The work in our laboratory is funded the Instituto de Salud Carlos III (FIS PI19/01030) to SC. Institutional grants from the Fundacion ´ Ramon ´ Areces and Banco de Santander to the CBMSO are also acknowledged.S

    Aging-Associated miR-217 Aggravates Atherosclerosis and Promotes Cardiovascular Dysfunction.

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    microRNAs are master regulators of gene expression with essential roles in virtually all biological processes. miR-217 has been associated with aging and cellular senescence, but its role in vascular disease is not understood. Approach and Results: We have used an inducible endothelium-specific knock-in mouse model to address the role of miR-217 in vascular function and atherosclerosis. miR-217 reduced NO production and promoted endothelial dysfunction, increased blood pressure, and exacerbated atherosclerosis in proatherogenic apoE-/- mice. Moreover, increased endothelial miR-217 expression led to the development of coronary artery disease and altered left ventricular heart function, inducing diastolic and systolic dysfunction. Conversely, inhibition of endogenous vascular miR-217 in apoE-/- mice improved vascular contractility and diminished atherosclerosis. Transcriptome analysis revealed that miR-217 regulates an endothelial signaling hub and downregulates a network of eNOS (endothelial NO synthase) activators, including VEGF (vascular endothelial growth factor) and apelin receptor pathways, resulting in diminished eNOS expression. Further analysis revealed that human plasma miR-217 is a biomarker of vascular aging and cardiovascular risk. Our results highlight the therapeutic potential of miR-217 inhibitors in aging-related cardiovascular disease.V.G. de Yébenes was supported by Ramón y Cajal grant RYC-2009-04503 and AECC foundation grant INVES18013GARC and by the Universidad Complutense de Madrid. S.M. Mur and A.R. Ramiro are supported by Centro Nacional de Investigaciones Cardiovasculares (CNIC) funding. A.R. Ramiro was supported by the Spanish Ministerio de Ciencia e Innovación (PID2019-107551RB-I00), the Spanish Ministerio de Economía, Industria y Competitividad (SAF2013-42767-R and SAF2016-75511-R), and the European Research Council StG BCLYM. M. Salaices was supported by the Ministerio de Ciencia e Innovación (SAF2016-80305P) and with J. Miguel Redondo by Instituto de Salud Carlos III (CIBER de Enfermedades Cardiovasculares, CB16/11/00286 and CB16/11/00264) and Comunidad de Madrid (B2017/BMD-3676). V.G. de Yébenes was supported by Ministerio de Ciencia e Innovación (PID2019-107551RB-I00). Further support was provided by the European Social Fund and the European Regional Development Fund “A Way to Build Europe.” The CNIC is supported by Ministerio de Ciencia, Innovacion y Universidades, and the Pro CNIC Foundation and is a Severo Ochoa Center of Excellence (SEV-2015-0505).S

    Effectiveness of Fosfomycin for the Treatment of Multidrug-Resistant Escherichia coli Bacteremic Urinary Tract Infections

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    IMPORTANCE The consumption of broad-spectrum drugs has increased as a consequence of the spread of multidrug-resistant (MDR) Escherichia coli. Finding alternatives for these infections is critical, for which some neglected drugs may be an option. OBJECTIVE To determine whether fosfomycin is noninferior to ceftriaxone or meropenem in the targeted treatment of bacteremic urinary tract infections (bUTIs) due to MDR E coli. DESIGN, SETTING, AND PARTICIPANTS This multicenter, randomized, pragmatic, open clinical trial was conducted at 22 Spanish hospitals from June 2014 to December 2018. Eligible participants were adult patients with bacteremic urinary tract infections due to MDR E coli; 161 of 1578 screened patients were randomized and followed up for 60 days. Data were analyzed in May 2021. INTERVENTIONS Patients were randomized 1 to 1 to receive intravenous fosfomycin disodium at 4 g every 6 hours (70 participants) or a comparator (ceftriaxone or meropenem if resistant; 73 participants) with the option to switch to oral fosfomycin trometamol for the fosfomycin group or an active oral drug or pa renteral ertapenem for the comparator group after 4 days. MAIN OUTCOMES AND MEASURES The primary outcome was clinical and microbiological cure (CMC) 5 to 7 days after finalization of treatment; a noninferiority margin of 7% was considered. RESULTS Among 143 patients in the modified intention-to-treat population (median [IQR] age, 72 [62-81] years; 73 [51.0%] women), 48 of 70 patients (68.6%) treated with fosfomycin and 57 of 73 patients (78.1%) treated with comparators reached CMC (risk difference, -9.4 percentage points; 1-sided 95% CI, -21.5 to infinity percentage points; P = .10). While clinical or microbiological failure occurred among 10 patients (14.3%) treated with fosfomycin and 14 patients (19.7%) treated with comparators (risk difference, -5.4 percentage points; 1-sided 95% CI. -infinity to 4.9; percentage points; P = .19), an increased rate of adverse event-related discontinuations occurred with fosfomycin vs comparators (6 discontinuations [8.5%] vs 0 discontinuations; P = .006). In an exploratory analysis among a subset of 38 patients who underwent rectal colonization studies, patients treated with fosfomycin acquired a new ceftriaxone-resistant or meropenem-resistant gram-negative bacteria at a decreased rate compared with patients treated with comparators (0 of 21 patients vs 4 of 17 patients [23.5%]; 1-sided P = .01). CONCLUSIONS AND RELEVANCE This study found that fosfomycin did not demonstrate noninferiority to comparators as targeted treatment of bUTI from MDR E coli; this was due to an increased rate of adverse event-related discontinuations. This finding suggests that fosfomycin may be considered for selected patients with these infections

    The role of native lichens in the biomonitoring of gaseous mercury at contaminated sites

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    Contamination by atmospheric mercury has been assessed in two different areas from Spain (Las Cuevas, Ciudad Real and Flix, Tarragona) using lichens as biomonitors. The relationship established between mercury contents in the soils and the gaseous mercury (GM) was also observed. It was found that the GM is highest in the vicinity of the source and it is dispersed depending on of the distance to the source and the wind directions. The mercury concentration in the gas phase in Flix was higher than that found in Las Cuevas and also higher than the value that the US EPA recommended. The mercury bioaccumulation in the native lichens from genders Ramalina and Xanthoria were used as biomonitors for absorbing mercury in Las Cuevas and Flix, respectively. The mercury uptake by Ramalina was higher than the amount accumulated by Xanthoria, a difference that was mainly due to the lichen characteristics. The content of mercury in lichens in relation to the mercury in gas was fitted by a Freundlich type equation, indicating that the equilibrium between both phases was established. Besides, transplanted Ramalina lichen in Las Cuevas allowed to obtain the kinetic of mercury uptake. A kinetic model of first order based on the equilibrium was proposed and the mass transfer constants for each sampling station were estimated. As it was expected, these values increased with the predominant wind flow direction.This work was funded by LIFE-Environment Project LIFE06 ENV/ES/PREP/03, as well as by Spanish Ministry of Economy and Competitiveness, though the Projects CTM2012-33918 and CGL2015-67644-R

    Thermal testing and numerical simulation of gypsum wallboards incorporated with different PCMs content

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    A mathematical model based on the Fourier heat conduction equation for one dimension was developed. The complexity of the mathematical solution of this stiff set of differential equations that use boundary conditions that move with the solid-liquid interface was simplified by using an apparent heat capacity () dependent on temperature and obtained by Modulated Differential Scanning Calorimetry (MDSC). The performance of this model was confirmed by using a home-made experimental installation for the thermal characterization of solid materials. Theoretical curves obtained for gypsum blocks with three different contents of phase change materials (PCMs) were in agreement with experimental ones, indicating that this thermal process can be reproduced theoretically by using the of each block and a unique thermal conductivity of the pure gypsum. The other physical and thermal properties were taken from literature or supplied by the manufacturers. Results also indicated that the higher the PCM content, the higher the energy storage capacity of the wallboard and the lower the wall temperature variation. Furthermore, it was found that a block containing a 5 wt.% of microcapsule allows the reduction of gypsum thickness by 8.5%, maintaining the same insulating effect. Thus, these kind of material can be used to improve comfort, save energy in buildings and even reduce the weight of wallboards.PCM Heat capacity Thermal conductivity Gypsum

    Synthesis of aminophosphonate polyols and polyurethane foams with improved fire retardant properties

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    Aminophosphonated polyols with flame retardant properties are synthesized by ring opening polymerization using diethyl-N,N-bis(2-hydroxyethyl) aminomethyl phosphonate (Fyrol-6) as initiator. The influence of the catalyst type and its concentration on the polymerization rate are studied. The catalyst system formed by potassium methoxide (MeOK) in DMSO as a solvent presents the highest polymerization rate and allows reducing the polydispersity. The thermal resistance of the synthesized polyols is confirmed by the char residues formation. Finally, PU foams are synthesized containing up to a 50 pph of PFyCs[1:1], preserving good cellular structure up to a 25 pph content and improving the fire resistance by increasing the char residue from 7.79 to 22.13 wt % and decreasing the PHRR and the smoke production according to TGA and cone calorimeter tests, respectivelyLos polioles aminofosfonados con propiedades ignífugas se sintetizan mediante polimerización con apertura de anillo utilizando dietil-N,N-bis(2-hidroxietil)aminometilfosfonato (Fyrol-6) como iniciador. Se estudia la influencia del tipo de catalizador y su concentración en la velocidad de polimerización. El sistema catalizador formado por metóxido de potasio (MeOK) en DMSO como solvente presenta la mayor tasa de polimerización y permite reducir la polidispersidad. La resistencia térmica de los polioles sintetizados se confirma por la formación de residuos de carbón. Finalmente, se sintetizan espumas de PU que contienen hasta 50 pph de PFyCs[1:1], conservan una buena estructura celular hasta un contenido de 25 pph y mejoran la resistencia al fuego al aumentar el residuo carbonizado de 7,79 a 22,13 % en peso y disminuir el PHRR y la producción de humo según TGA y pruebas de calorímetro de cono, respectivament
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