Facultad Regional Córdoba
Permanent URI for this communityhttp://48.217.138.120/handle/20.500.12272/94
Browse
8 results
Search Results
Item Reservorio nanoscópico de hidrógeno a partie de biorresiduos de cáscara de naranjas.(Univesidsad Tecnológica Nacional., 2022) Juárez , Juliana María; Ledesma , Brenda Cecilia; Anunziata , Oscar Alfredo; Gómez Costa , Marcos Bruno; Beltramone , Andrea Raquel; Anunziata , Oscar Alfredo; Ledesma , Brenda CeciliaEste trabajo aborda el enfoque de valorización de biorresiduos para el desarrollo de un novedoso nanomaterial carbonoso para ser utilizado en la adsorción de hidrógeno como una alternativa en el uso de hidrógeno verde. En esta investigación, los carbones activados se sintetizaron a partir de cáscara de naranja utilizando diferentes condiciones de síntesis. Con los carbones activados obtenidos con la mejor estructura y textura se estudió la adsorción de hidrógeno y los efectos en la meso/microporosidad de estos. La activación del carbón se realizó mediante un proceso químico con ácido fosfórico como agente activador, variando la concentración de ácido, la relación sustrato / agente activador y el tiempo de contacto entre ellos. El mejor material se obtuvo utilizando tiempo de carbonización de 1 h, temperatura de carbonización de 470oC, concentración de ácido fosfórico de 50% en peso y con área BET de 1402 m2 / g. Dicho material mejoró significativamente el comportamiento de almacenamiento de H2 en comparación con el carbón nanoestructurado del tipo CMK-3 (3,1% en peso a -196,15 oC y 10 bar). El material sintetizado es prometedor en la absorción de hidrógeno por fuerzas de enlace débiles (fisisorción).Item Síntesis directa del carbón mesoporoso ordenado CMK-3 modificado con circonio en almacenamiento de energía.(Univesidsad Tecnológica Nacional., 2020) Venosta, Lisandro; Juárez , Juliana María; Anunziata , Oscar Alfredo; Gómez Costa , Marcos Bruno; Anunziata , Oscar Alfredo; Juárez , Juliana MaríaEn este trabajo, informamos la síntesis y caracterización del material de carbono nanoestructurado (CMK-3) modificado con óxido de circonio sintetizado por una nueva técnica de síntesis directa. Este material es prometedor en la aplicación de adsorción de hidrógeno para el almacenamiento de energía. Los materiales con óxido de circonio (Zr-CMK-3) se sintetizaron con éxito y se caracterizaron por difracción de rayos X, propiedades texturales, UV-Vis-DRS, XPS y análisis de microscopía electrónica de transmisión. El material Zr-CMK-3 mejoró significativamente el comportamiento de almacenamiento de H2 (4,6% en peso a 77 K y 10 bar) en comparación con el soporte CMK-3. El material sintetizado es prometedor en la absorción de hidrógeno por fuerzas de enlace débiles (fisisorción). Se propuso un mecanismo de adsorción de hidrógeno y se discutió el rol de catión Zr+4 en la absorción de hidrógeno. Palabras clave: Circonio, CMK-3, Hidrógeno, Almacenamiento, EnergíaItem Vanadium and titanium oxide supported on mesoporous CMK-3 as new catalysts for oxidative desulfurization.(Univesidsad Tecnológica Nacional., 2016) Rivoira , Lorena Paola; Juárez , Juliana María; Falcón , Horacio; Gómez Costa , Marcos Bruno; Anunziata , Oscar Alfredo; Beltramone, Andrea Raquel; Anunziata , Oscar Alfredo; Juárez , Juliana MaríaVanadium supported-CMK-3 catalysts with vanadium loading of 1–7 wt.% were studied in the oxidative desulfurization (ODS) of dibenzothiophene as a model sulfur compound. The activity was compared with titanium supported-CMK-3. Structural and textural characterization of the catalysts was performed by means of N2 adsorption, XRD, UV–vis–DRS, Raman spectroscopy, XPS, TEM and TPR. The dispersion and the nature of the vanadium species depend on the V loading, so does the catalyst activity. Vanadium supported-CMK-3 with 7 wt.% of vanadium loading was the most active catalyst for ODS of DBT using hydrogen peroxide (H2O2) as oxidant and acetonitrile as solvent. 100% of DBT elimination was attained at short time in mild conditions. Carbon ordered mesoporous CMK-3 with high surface area and high pore volume promotes a very good anchorage of metallic oxides in the carbons framework reaching high active sites distribution and more stable nanoclusters. The reusability of the catalyst indicates that V-CMK-3 is a potential catalyst for the ODS of dibenzothiopheneItem Ordered mesoporous SBA-15 host for Ketorolac-Tromethamine loading and release behavior.(Univesidsad Tecnológica Nacional, 2017) Cussa , jorgelina; Juárez , Juliana María; Gómez Costa , Marcos Bruno; Anunziata , Oscar Alfredo; Anunziata , Oscar Alfredo; Juárez , Juliana MaríaThe ordered mesoporous silica SBA-15 has been applied in studies of ketorolac tromethamine adsorption and release. The SBA-15 materials with hexagonal and regular structure were obtained using a triblock copolymer Pluronic P123 as a template and TEOS as a silica source. Ketorolac tromethamine was adsorbed into SBA-15 silica nanochannels using ethanol as solvent. The physicochemical and textural properties of SBA-15 and ketorolac tromethamine/SBA-15 were characterized by X-ray diffraction, thermogravimetric analysis, transmission electron microscopy, Fourier transform infrared spectroscopy and BET surface studies. The composite SBA-15/KETO shows characteristic bands of both, drug materials and the inorganic framework. This indicates that KETO was adsorbed into SBA-15 channel surface without affecting the chemical structure or composition of KETO. Drug release was evaluated by soaking the loaded silica mesoporous material into a solution of HCl (0.1N) at initial time (0 - 2 h) and buffer pH 7 at high times at 37 ºC under continuous stirring. Oral commercial Keto tablets (Dolten®) and Keto solution (Keto power) were study for the contrast. Release studies were performed in order to evaluate the required therapeutic efficacy. SBA-15 provides significant improvement in the controlled release of ketorolac tromethamine and enhance a good analgesia effect.Item Synthesis, characterization of nanoporous SBA-15 host and application in Ketorolac-Tromethamine release system.(Univesidsad Tecnológica Nacional, 2016) Juárez , Juliana María; Cussa , jorgelina; Gómez Costa , Marcos Bruno; Anunziata , Oscar Alfredo; Anunziata , Oscar Alfredo; Cussa , jorgelinaControlled release technologies are growing in importance in modern medication and pharmaceutical industries. Drug delivery is an emerging field mainly focused on targeting drugs. The goal of this targeted delivery is to transport an amount of drugs to desirable sites (such as tumors and diseased tissues) while minimizing unwanted side effects of the drugs on other tissues [1]. Generally, controlled drug delivery systems can maintain the concentration of drugs in the precise sites of the body within the optimum range and under the toxicity threshold, improving therapeutic efficacy and reducing toxicity [2]. Nanotechnology will produce significant results; hence, the drug is controlled during days or even weeks, depending on the disease that needs to be treated. In recent years mesoporous silicas have been used for hosting and further delivery of various biomolecules and drugs [3]. SBA-15 is a crystalline mesoporous molecular framework with an ordered and precise mesoporous hexagonally system. This material shows uniform channels and a pore diameter that can be varied systematically between 1.5 and 10 nm with surfactant as the template, auxiliary chemicals and reaction conditions. Ketorolac tromethamine (KETO) is a pyrrolizine carboxylic acid derivative of NSAIDs with potent analgesic and moderate anti-inflammatory activity; it is a relatively favorable therapeutic agent for the treatment of moderate to severe pain. The main goal of this study is the adsorption capacity and storage properties of SBA-15/ KETO release in achieving the required therapeutic efficacyItem Ketorolac-tromethamine contained in SBA-15 host as a drug release system,(Univesidsad Tecnológica Nacional, 2017) Cussa , jorgelina; Prados, Antonella; Juárez , Juliana María; Gómez Costa , Marcos Bruno; Anunziata , Oscar Alfredo; Anunziata , Oscar Alfredo; Juárez , Juliana MaríaDrug delivery is an emerging field mainly focused on targeting drugs. The goal of this targeted delivery is to transport an amount of drugs to desirable sites (such as tumors and diseased tissues) while minimizing unwanted side effects of the drugs on other tissues[1]. Controlled drug delivery systems can achieve precise spatial and temporal delivery of therapeutic agents to the target site[2]. The ordered mesoporous silica SBA-15 has been applied in studies of ketorolac tromethamine adsorption and release. The SBA-15 materials with hexagonal and regular structure were obtained using a triblock copolymer Pluronic P123 as a template and TEOS as a silica source[3]. Ketorolac tromethamine was adsorbed into SBA-15 silica nanochannels using ethanol as solvent. The physicochemical and textural properties of SBA-15 and ketorolac tromethamine/SBA-15 were characterized by X-ray diffraction, thermogravimetric analysis, transmission electron microscopy, Fourier transform infrared spectroscopy and BET surface studies. Drug release was evaluated by soaking the loaded silica mesoporous material into a solution of HCl (0.1N) at initial time (0 - 2 h) and buffer pH 7 at high times at 37 ºC under continuous stirring. Oral commercial Keto tablets (Dolten®) and Keto solution (Keto power) were study for the contrast. Release studies were performed in order to evaluate the required therapeutic efficacy. In this work, we have shown a promising drug storage material for the effective encapsulation and controlled release of KETO, achieving the required therapeutic efficacy. SBA-15/KETO shows characteristic bands of both, drug materials and the inorganic framework. This indicates that KETO was adsorbed into SBA-15 channel surface without affecting the chemical structure or composition of KETO. The study also demonstrates the storage capacity and release properties of SBA-15 containing KETO. The release of KETO contained in SBA-15 can offer significant improve in controlled drug release and enhance a good analgesia effect.Item H2 storage using Zr-CMK-3 developed by a new synthesis method.(Univesidsad Tecnológica Nacional, 2021) Juárez , Juliana María; Venosta , Lisandro; Anunziata, Oscar Alfredo; Gómez Costa , Marcos Bruno; Anunziata, Oscar AlfredoOne of the biggest problems in using hydrogen as an alternative fuel is that its storage must be safe and portable. This work addresses a new direct synthesis technique used to obtain a novel mesoporous carbon (CMK-3) modified with zirconium oxide. This novel material shows promise for hydrogen adsorption and storage application for energy harvesting. Zirconium oxide (Zr-CMK-3) material is achieved through successful synthesis and characterized by XRD, SEM,Raman, BET, UV-Vis-DRS, XPS and TEM analyses. Zr-CMK-3 signifi- cantly improved H2 storage performance (reaching at 77 K and 10 bar 4.6 wt%) comparedto the pristine CMK-3. The novel material is favorable for H2 uptake by using weak bonding (physisorption). A hydrogen uptake mechanistic approach is proposed and the role of the Zr+4 cation in hydrogen adsorption is discussed.Item Synthesis and characteristics of CMK-3 modified with magnetite nanoparticles for application in hydrogen storage.(Univesidsad Tecnológica Nacional, 2020) Venosta, Lisandro; Juárez , Juliana María; Anunziata , Oscar Alfredo; Bercoff, Paula; Gómez Costa , Marcos Bruno; Anunziata , Oscar Alfredo; Juárez , Juliana María: In this work, we report the synthesis and characterization of iron oxide nanoparticles supported in nanostructured carbon (CMK-3). This material is promising in the application of hydrogen adsorption for energy storage. The material with iron oxide nano particles (Fe-CMK-3) was successfully synthesized and characterized by X-ray diffraction, textural properties analysis, transmission and scanning electron microsco py, X-ray photoelectron spectroscopy, and magnetiza tion studies. A large amount of the iron incorporated as iron oxide nanoparticles was in the magnetite phase. The incorporation of magnetite on the CMK-3 carbon surface significantly improved the storage capacity of hydrogen (4.45 wt% at 77 K and 10 bar) compared with the CMK-3 framework alone (2.20 wt% at 77 K and 10 bar). The synthesized material is promising for hy drogen adsorption by weak bond forces (physisorption). A hydrogen adsorption mechanism was proposed in which the nanoparticles of magnetite have an important role.