Person: Martín Martínez, María
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First Name
María
Last Name
Martín Martínez
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Ciencias Químicas
Department
Ingeniería Química y de Materiales
Area
Ingeniería Química
Identifiers
21 results
Search Results
Now showing 1 - 10 of 21
- Project number: PIMCD405/23-24
Item Dando a conocer la Ingeniería Química: del bachillerato a la Universidad… y vuelta!(2024) Martín Martínez, María; Águeda Maté, Vicente Ismael; Álvarez Torrellas, Silvia; Carbajo Olleros, Jaime; Delgado Dobladez, José Antonio; García Rodríguez, Juan; Larriba Martínez, Marcos; Calero Berrocal, Ruben; Cañada Barcala, Andres; Huber Benito, Diego; Martin Gutierrez, Diego; Pascual Muñoz, Gonzalo; Peinado Serrano, M. Cristina; Pinzolas Rubio, Alejandro; Portillo Sanchez, Eva; Rodriguez Llorente, Diego; Sanchez Quiñones, Carlos A. A.; Sanchez Fernandez, Ignacio - Project number: 208
Item Practicando Ingeniería Química: Prácticas colaborativas de bajo coste para grupos numerosos() Larriba Martínez, Marcos; Ovejero Escudero, Gabriel; García Rodríguez, Juan; Delgado Dobladez, José Antonio; Águeda Maté, Vicente Ismael; Álvarez Torrellas, Silvia; Martín Martínez, María; Carbajo Olleros, Jaime; García Sánchez, Laura; Guerrero Moreno, Elisa; Aranda López, Daniel; Serra Pérez, Estrella; Pascual Muñoz, Gonzalo; Rodríguez Llorente, Diego; Cañada Barcala, Andrés; Sanz Santos, Eva; Gutiérrez Sánchez, Pablo; Calero Berrocal, Rubén; Sánchez Quiñones, Carlos Alberto Augusto; Cañas Jiménez, Javier; Huber Benito, Diego; Portillo Sánchez, Eva; Martín Gutiérrez, Diego; Suárez Rodríguez, Pablo; Sánchez Fernández, IgnacioElaboración de un catálogo de prácticas de laboratorio de bajo coste para trabajar los fundamentos de ingeniería química con grupos numerosos, usando metodologías activas de aprendizaje para incrementar la motivación de los estudiantes. Item Areas of Interest and Social Consideration of Antidepressants on English Tweets: A Natural Language Processing Classification Study(Journal of Personalized Medicine, 2022) Anta, Laura de; Álvarez Mon, Miguel Ángel; Ortega Campos, Miguel Ángel; Salazar, Cristina; Donat Vargas, Carolina; Santoma Vilaclara, Javier; Martín Martínez, María; Lahera, Guillermo; Gutierrez Rojas, Luis; Rodríguez Jiménez, Roberto; Quintero, Javier; Álvarez Mon, MelchorBackground: Antidepressants are the foundation of the treatment of major depressive disorders. Despite the scientific evidence, there is still a sustained debate and concern about the efficacy of antidepressants, with widely differing opinions among the population about their positive and negative effects, which may condition people’s attitudes towards such treatments. Our aim is to investigate Twitter posts about antidepressants in order to have a better understanding of the social consideration of antidepressants. Methods: We gathered public tweets mentioning antidepressants written in English, published throughout a 22-month period, between 1 January 2019 and 31 October 2020. We analysed the content of each tweet, determining in the first place whether they included medical aspects or not. Those with medical content were classified into four categories: general aspects, such as quality of life or mood, sleep-related conditions, appetite/weight issues and aspects around somatic alterations. In non-medical tweets, we distinguished three categories: commercial nature (including all economic activity, drug promotion, education or outreach), help request/offer, and drug trivialization. In addition, users were arranged into three categories according to their nature: patients and relatives, caregivers, and interactions between Twitter users. Finally, we identified the most mentioned antidepressants, including the number of retweets and likes, which allowed us to measure the impact among Twitter users. Results: The activity in Twitter concerning antidepressants is mainly focused on the effects these drugs may have on certain health-related areas, specifically sleep (20.87%) and appetite/weight (8.95%). Patients and relatives are the type of user that most frequently posts tweets with medical content (65.2%, specifically 80% when referencing sleep and 78.6% in the case of appetite/weight), whereas they are responsible for only 2.9% of tweets with non-medical content. Among tweets classified as non-medical in this study, the most common subject was drug trivialization (66.86%). Caregivers barely have any presence in conversations in Twitter about antidepressants (3.5%). However, their tweets rose more interest among other users, with a ratio 11.93 times higher than those posted by patients and their friends and family. Mirtazapine is the most mentioned antidepressant in Twitter (45.43%), with a significant difference with the rest, agomelatine (11.11%). Conclusions: This study shows that Twitter users that take antidepressants, or their friends and family, use social media to share medical information about antidepressants. However, other users that do not talk about antidepressants from a personal or close experience, frequently do so in a stigmatizing manner, by trivializing them. Our study also brings to light the scarce presence of caregivers in Twitter.- Project number: 142
Item Lab at home: prácticas experimentales de Ingeniería Química en tiempos de pandemia(2022) Larriba Martínez, Marcos; Ovejero Escudero, Gabriel; García Rodríguez, Juan; Delgado Dobladez, José Antonio; Águeda Maté, Vicente Ismael; Álvarez Torrellas, Silvia; Martín Martínez, María; García Sánchez, Laura; Peinado Serrano, María Cristina; Serra Pérez, Estrella; Pascual Muñoz, Gonzalo; Rodríguez Llorente, Diego; Cañada Barcala, Andrés; Sanz Santos, Eva; Gutiérrez Sánchez, Pablo; Calero Berrocal, Rubén; Sánchez Quiñones, Carlos Alberto Augusto; Cañas Jiménez, Javier; Santos Sanz, Alberto; Carreras Navarro, Francisco Javier; Sánchez Morales, Laura Laila; Nájera García, Roberto Item Removal of chlorinated organic volatile compounds by gas phase adsorption with activated carbon(Chemical Engineering Journal, 2012) Lemus, Jesus; Martín Martínez, María; Palomar, Jose; Gomez-Sainero, Luisa; Gilarranz Redondo, Miguel Ángel; Rodriguez, Juan J.This paper discusses the removal of chlorinated volatile organic compounds (Cl-VOCs) from gas streams by means of fixed-bed adsorption with a commercial activated carbon (AC). Column experiments were performed at different conditions (inlet concentration, temperature, pressure, gas flow rate and bed length). A two-parameter model introduced by Yoon and Nelson was applied to predict the entire breakthrough curves for chloromethane adsorption. Complete regeneration of the exhausted AC was performed at mild conditions (atmospheric pressure and room temperature). In order to gain a better knowledge on the effect of the surface chemistry of AC on the adsorption of Cl-VOCs, the quantum-chemical COSMO-RS method was used to simulate the interactions between AC surface groups and different Cl-VOCs as monochloromethane, dichloromethane and trichloromethane. This information can be useful for tailoring the ACs with the objective of improving their adsorption capacities by further functionalization. To confirm this, the commercial AC tested was modified by means of different thermal and oxidative treatments (nitric acid and ammonium persulfate), being the surface chemistry and textural properties of the resulting materials characterized by different techniques. The modified ACs were then tested in column adsorption experiment with different Cl-VOCs. The uptake of these compounds increased with the basic character of the AC surface.Item Catalizadores bimetálicos (Pd-Pt) soportados sobre óxido de zirconio sulfatado y su uso en la hidrodecloración de clorometanos(2014) Gómez-Sainero, Luisa Maria; Grau, Javier Mario; Rodriguez, Juan Jose; Bedia, Jorge; Martín Martínez, María; Montero Álvarez, Daniel; Busto, Mariana; Universidad Autónoma de MadridCatalizadores bimetálicos (Pt-Pd) soportados sobre óxido de zirconio sulfatado y su uso en la hidrodecloración de clorometanos. La presente invención se refiere a catalizadores bimetálicos soportados en zirconia sulfata y a la preparación, activación y operación de los mismos, junto con el uso de los catalizadores mono y bimetálicos para la hidrodecloración de clorometanos en condiciones moderadas de presión y temperatura.Item Catalizadores de alta estabilidad para la hidrodecloración de clorometanos(2011) Alvarez-Montero, Ariadna; Rodriguez, Juan Jose; Martín Martínez, María; Gómez-Sainero, Luisa Maria; Universidad Autónoma de MadridLa presente invención describe un procedimiento para la preparación de un catalizador de Pt soportado sobre carbón, que comprende la preparación de una solución acuosa ácida de una sal de Pt, y la impregnación con dicha solución de un carbón con marcado carácter básico o neutro, el cual que presenta una desorción de CO{sub,2} inferior a 100 {mi}moles/gramo de carbón, así como un catalizador obtenible según dicho procedimiento y el uso de dicho catalizador en el tratamiento de efluentes gaseosos residuales contaminados con clorometanos.Item Exploring the activity of chemical-activated carbons synthesized from peach stones as metal-free catalysts for wet peroxide oxidation(Catalysis Today, 2018) Martín Martínez, María; Álvarez Torrellas, Silvia; García Rodríguez, Juan; Adrián M.T. Silva; Joaquim L. Faria; Helder T. GomesPeach stones were used as raw material for the synthesis of activated carbons with different properties. Firstly, peach stones were chemically activated using a 12M H3PO4 solution and carbonized under flowing air (400 °C). The obtained activated carbon, named as PS, is characterized by a high surface development (SBET=1262m2 g−1) and acidic character (pHPZC=4.2). A fraction of PS was further carbonized under N2 atmosphere at 800 °C to remove surface functionalities and to increase its basicity (PS-800). In addition, a Pt catalyst supported on PS (3% w/w Pt/PS) was synthesized by incipient wetness impregnation, resulting in a considerable hydrophilicity increasing. The synthesized materials were tested in the catalytic wet peroxide oxidation (CWPO) of highly concentrated solutions of 4-nitrophenol (4-NP, 5 g L−1) during 24 h experiments, conducted at relatively mild operating conditions (T=50–110 °C, pH=3, catalyst load=2.5 g L−1 and [H2O2]0=17.8 g L−1, corresponding to the stoichiometric amount of H2O2 needed for the complete mineralization of 4-NP). It was observed that the increase of electron-donating functionalities in PS-800 promotes the generation of reactive HO% radicals, being the activity towards CWPO twice higher than that obtained with the pristine PS. Besides, increasing operating temperature substantially enhances CWPO, finding a 80% of 4-NP removal at 110 °C. On the other hand, despite the sharp increment in H2O2 decomposition due to the presence of Pt particles in Pt/PS catalyst, this decomposition is inefficient in all cases, with a consequent poor pollutant removal. This can be attributed to the recombination of HO% radicals into non-reactive species −scavenging effects, promoted by the hydrophilicity of the catalyst.Item Role of Nitrogen Doping on the Performance of Carbon Nanotube Catalysts: A Catalytic Wet Peroxide Oxidation Application(ChemCatChem, 2016) Martín Martínez, María; Rui S. Ribeiro; Bruno F. Machado; Philippe Serp; Sergio Morales‐Torres; Adrián M. T. Silva; José L. Figueiredo; Joaquim L. Faria; Helder T. GomesFour magnetic carbon nanotube (CNT) samples (undoped, completely N-doped, and two selectively N-doped) were synthesized by chemical vapor deposition. The materials were tested in the catalytic wet peroxide oxidation (CWPO) of highly concentrated 4-nitrophenol solutions (4-NP, 5 g L−1). Relatively mild operating conditions were considered (atmospheric pressure, T=50 °C, pH 3), using a catalyst load of 2.5 g L−1 and the stoichiometric amount of H2O2 needed for the complete mineralization of 4-NP. N-doping was identified to influence considerably the CWPO performance of the materials. In particular, undoped CNTs, with a moderate hydrophobicity, favor the controllable and efficient decomposition of H2O2 into highly reactive hydroxyl radicals (HO.), thus showing high catalytic activity for 4-NP degradation. On the other hand, the completely N-doped catalyst, fully hydrophilic, favors a quick decomposition of H2O2 into nonreactive O2 and H2O species. The selectively N-doped amphiphilic catalysts, that is, hybrid structures containing undoped sections followed by N-doped ones, provided intermediate results, namely, a higher N content favored H2O2 decomposition towards nonreactive H2O and O2 species, whereas a lower N content resulted in the formation of HO., increasing 4-NP mineralization. Catalyst stability and reusability were also investigated by consecutive CWPO runs.Item Structure sensitivity reaction of chloroform hydrodechlorination to light olefins using Pd catalysts supported on carbon nanotubes and carbon nanofibers(Journal of Colloid and Interface Science, 2023) Sichen Liu; Carlos Fernandez-Ruiz; Ana Iglesias-Juez; Martín Martínez, María; Jorge Bedia; Carlo Marini; Giovanni Agostini; Juan José Rodriguez; Luisa María Gómez-SaineroThe upgrading of wasted chloroform in hydrodechlorination for the production of olefins such as ethylene and propylene is studied by employing four catalysts (PdCl/CNT, PdCl/CNF, PdN/CNT, and PdN/CNF) prepared by different precursors (PdCl2 and Pd(NO3)2) supported on carbon nanotubes (CNT) or carbon nanofibers (CNF). TEM and EXAFS-XANES results confirm that Pd nanoparticle size increases in the order: PdCl/CNT < PdCl/CNF ∼ PdN/CNT < PdN/CNF, descending the electron density of Pd nanoparticles in the same order. It illustrates that PdCl-based catalysts show donation of electrons from support to Pd nanoparticles, which is not observed in PdN-based catalysts. Moreover, this effect is more evident in CNT. The smallest and well-dispersed Pd nanoparticles (NPs) on PdCl/CNT with high electron density favor an excellent and stable activity and a remarkable selectivity to olefins. In contrast, the other three catalysts show lower selectivity to olefins and lower activities which suffer strong deactivation due to the formation of Pd carbides on their larger Pd nanoparticles with lower electron density, compared to PdCl/CNT
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