Desarrollo, Producción e Innovación en la Investigación científica
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Item Effect of geogrid reinforcement on interface for a stratified embankment(Geotech., 2016) Useche Infante, Danny José; Aiassa Martínez, Gonzalo Martín; Arrúa, Pedro Ariel; Eberhardt, Marcelo GabrielReinforced granular embankments are often placed on soft soil strata for an efficient and economical transfer of superstructure load. This paper describes laboratory tests on circular footing supported on unreinforced and geogrid-reinforced granular soil. Two types of geogrid layer, uniaxial and biaxial geogrid, were placed at the interface of sub-base soil and granular base of an embankment formed on soft ground to support shallow foundations. Load test were conducted with the aim to determine the performance improvement of the circular footing due to the provision of both types of geogrid reinforcement in the soil. Also studied the effect produced by anchoring geogrid layer at the edge of the mold sample. The results showed that the inclusion of a geogrid layer at the interface of sub-base soil and granular base increase the magnitude of the footing bearing capacity and decreases the settlement of the system. The study shows that the type of geogrid used has direct influence on stress-strain behavior of soil-geogrid system and better results occurred when the geogrid was anchored to test mold.Item Calibración de modelo hidromecánico en mezclas de loess y bentonita(Tecnología y Ciencia - UTN, 2016) Alercia Biga, Carolina; Arrúa, Pedro Ariel; Aiassa Martínez, Gonzalo Martín; Eberhardt, Marcelo GabrielLos suelos loessicos de la Ciudad de Córdoba, constituyen uno de los materiales más importantes empleados en obras de ingeniería especialmente en obras viales. Se han realizado importantes estudios investigando sus propiedades geotécnicas. En este trabajo, se realizaron ensayos de compresión no confinada y ensayos de infiltración mediante el empleo de un permeámetro a pared flexible. Se realizaron mezclas de suelo loessico con adición de bentonita en distintos porcentajes. Se evaluó el contenido de humedad, peso unitario seco y contenido de bentonita en las muestras remoldeadas. Se compararon los resultados obtenidos experimentalmente con los modelos propuestos mediante formulaciones matemáticas. Los resultados muestran que es posible lograr una aproximación entre el comportamiento hidromecánico teórico obtenido mediante la modelación y calibración de funciones racionales respecto del comportamiento empírico obtenido como resultado de ensayos en mezclas de suelo loessico estabilizadas con bentonita.Item Prediction of infiltration on small scale field tests performance in compacted loessic soil(Geotech., 2015) Aiassa Martínez, Gonzalo Martín; Arrúa, Pedro Ariel; Eberhardt, Marcelo GabrielSilty loess soils are widely spread on Córdoba city, Argentina. The ability to use this soil improved by compaction on embankments it is of interest to different types of local constructions, with purpose of reducing settlements and infiltration. This work research the water infiltration through compacted silty soils from Córdoba by small scale field test. Four small test embankments were constructed on natural soil with different compaction conditions using local silty soils. The site was characterized by typical geotechnical laboratory and field tests. The infiltration tests were performed using double ring infiltrometers for a time period around of 2 months. Results were used to field permeability estimated (kf) and these were compared with laboratory results (kl). Conclusions regarding the behavior observed in the field are presented.Item Hydraulic conductivity in loessic stabiblized soil(Geotech, 2015) Alercia Biga, Carolina; Arrúa , Pedro A.; Eberhardt, Marcelo G.; Aiassa Martínez, Gonzalo MartínLoessic soils are the main geological storage available as a building material in Cordoba, Argentina. They are a typically kind of clayed silty soil with a metastable structure. Their structure makes them sensitive to collapse and sliding upon wetting. This has an important influence on mechanical and hydraulic behavior. Thus, usually their hydraulic properties are modified by compaction methods or by bentonite addition. Infiltration tests were done using remolded samples and a flexible wall permeameter. Compression tests were executed in a universal compression machine. Were performed in addition, capillary rise assays. Water content, dry unit weight, and percentages of ionic stabilizer and bentonite have been studied. Experiment results were compared between mixtures with different percentages of additives. The results show that the infiltration volume decreases with increasing content of bentonite in all remoulded samples tested respect to those natural soil remoulded samples, and it has been identified that the addition of bentonite increases the compressive strength by 400%.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 Sulfated/Zr-containing mesoporous carbons: a promising nanostructured catalytic material.(Univesidsad Tecnológica Nacional., 2021) Anunziata , Oscar Alfredo; Martínez , María Laura; Martínez , María LauraIn this work, we report the successful preparation of a promising material with acidic properties from starch-derived mesoporous carbon (SMC), functionalized with sulfated zirconia (SZr-SMC). The process of assembling P123, starch, zirconia, and silicon produces ordered mesoporous carbon modified with Zr. Reaction time and temperature are essential to avoid the appearance of poorly assembled or unsightly structures, reducing the surface area and the size of the pores. SZr- SMC has a surface area of approximately 1300 m2/g, and a total pore volume of 0.94 cm3/g, composed mainly of mesoporous with an average pore size of 3.5 nm. The composition of the surface and the chemical states of the elements did not reveal ZrO2 as isolated clusters. Ammonia thermodesorption studies indicated that, SZr-SMC retains 2.49 mmol/g of NH3 at very high temperature, exhibiting a strong acidity. According to the data collected by infrared spectroscopy (FTIR), of pyridine desorbed at various temperatures, the total number of acidic sites was 2.36 mmol/g, and the distribution in weak - medium, strong, and super acidic sites was determined. The activity in the methylation of aniline and isopropanol dehydration indicated that the acid sites are strong, and have not redox properties. A new and promising catalytic material based on mesoporous carbons modified with sulfated Zr is developed, which opens a wide range of acid-catalyzed reactions applied to industrial and medical processes.Item HaP/SBA-3 Nanostructured Composite to Remove Fluoride Effectively from Contaminated Water.(Univesidsad Tecnológica Nacional., 2021) Cussa , jorgelina; López, Claudia; Anunziata , Oscar Alfredo; Anunziata , Oscar Alfredo; López, ClaudiaElectron Microscopy (SEM), Transmission Electron Microscopy (TEM) and textural properties, were successfully applied to remove fluoride from contaminated water. The proposed procedure to prepare HaP/SBA-3 was successful, which acts as supports to anchor the HaP crystals, in nanometer-scale (<2nm), with higher fluoride retention from contaminated water. The free OH- groups of HaP nanocrystals, within the host, facilitated the high-performance fluoride trapping. The fluoride retention activity was much higher than that of pure HaP and the composites HaP/SBA-15 and HaP/MCM-41. Keywords: F- retention; Contaminated water; HaP/SBA-3; NanocompositesItem Controlled drug release system: cyclophosphamide delivery contained in LP-SBA-15 functionalized with terbutylamine.(Univesidsad Tecnológica Nacional., 2023) Cussa, jorgelina; Juárez , Juliana María; Gómez Costa, Marcos Bruno; Anunziata , Oscar Alfredo; Anunziata , Oscar Alfredo; Juárez , Juliana MaríaControlled drug administration systems can keep the level of drugs in specific locations in the organism with low toxicity and above the optimal level. We suggest the LP-SBA15 material as a auspicious new host for drug delivery systems because of its low toxicity high biocompatibility and in vivo biodegradability. LP-SBA-15 materials were synthesized and functionalized using 0-15-30% of tert-butylamine (TBA) and used as effective drug delivery systems. The anticancer drug Cyclophosphamide (CP) is an alkylating compound which is a phosphoramide derivative and is habitually used in autoimmune diseases. Reactive oxygen species production has been related to the mechanism of CP-induced cell death or tumor cell killing. The activated metabolites of CP are released in both healthy and tumor tissues and destroy the cellular DNA and proteins as well as mitochondrial and lysosomal membranes. CP was loaded into the nanomaterial of the transporters and characterized by XRD, FTIR, TGA, TEM and texture, determining the adsorption capacity and its release. The release of the drug was studied for each material by simulating the physiological conditions and submerging the composite, at 37 °C with constant stirring, in a HCl solution (0.1 M) for the first two hours and in Buffer solution pH = 7 the following hours to simulate the conditions of the organism. Release experiment were conducted to determine the requisite efficacy of treatment. The study was performed by UV-Vis spectrophotometry to evaluate the amount of CP released. The mechanism of drug release from the LP-SBA-15 matrix was evaluated by adjusting the experimental data, being the Ritger-Peppas. The promising results we obtained for the controlled release of the drug in a controlled manner using the new material, reaching a quick initial release rate and maintaining a constant rate at high moments, allow us to keep the concentration of the drug in the therapeutic efficacy range, applying it to a great extent to the treatment of diseases that require a rapid response. Lastly, it was suggested that the LP-SBA-15 nanomaterial functionalized with 15% TBA was the most desirable system due to they had adequate amounts of both drug loading and release.Item Controlled Release of Haloperidol from a novel SWCNT Nano composite coated with ZnO nanocrystals.(Univesidsad Tecnológica Nacional., 2023) Anunziata , Oscar Alfredo; Cussa , jorgelina; Martínez , María Laura; Martínez , María Laura; Cussa , jorgelinaStarting from the physicochemical knowledge of the host properties of the na noscale systems would be applied to drug dosage [1,2]. We propose NM synthesis strategies that offer the necessary characteristics for these processes. First, we study the physicochemistry of the anchoring sites of the respective hosts (chemical bonds with reversible or irreversible adsorption) or physisorption (straightforward interactions). Then, whether to design carbon based nanomaterials (CNM), or nano engineered materials, containing the respective active sites (deposited or generated nanospecies), capable of interacting with the aforementioned hosts such as: redox sites, proton acceptor sites, electron donor-acceptor sites, to allow HOMO-LUMO chemical interactions that satisfy the needs of the process to be studied. The nanostructures that allow free diffusions and reversible adsorptions, dosage of molecules with applications in nanokinetics, etc., and determination of critical molecular sizes, calculated using experimental methods, and methods such as density functional theory and semiempirical methods, to avoid steric hindrances between molecules and 100 80 40 60 8 12 16 20 Experimental data Weibull Ritger-Peppas Higuchi Drug Released , % mol/w Time (h) 4 20 nanomaterials whether 2D or 3D, designing NMs with large surface area, physical, ther mal and chemical stability, and pore size, and adequate pore size. Advancing in this sense, this work studies the usage of: Haloperidol Release from ZnO nanocrystal Coated SWCNT, with 30nm of wide and 5 um of long, which by the effect of the interaction between the host and drug molecules and by diffusion through the porosity, leads to a substantial contribution to controlled drug release. The reduction in the dose and frequency of administration, possible improvement in the selectivity of the pharmacological activity, and a prolonged therapeutic effect. CNT prepared by sol gel method (using the same technique describe by us, [3]), but at different pH and long range of pristine mesoporous carbons material calcination, to obtain SWCNTs. The posterior deposition of ZnO, was obtained, employing ZnNO3, activated under N2 flow at 500ºC; offering adequate LUMO of Zn (the hybridized MO) for Haloperidol interactions. Haloperidol competitively blocks postsynaptic dopamine (D2) receptors in the meso limbic system of the brain, thereby eliminat ing dopamine neurotransmission and leading to antidelusionary and antihallucinagenic effects. Specifically, the dose of Haloperidol (potent antipsychotic drug), indicates that its release follows the so called "power law" or Weibull model, based on the results we obtained in our laboratoryItem Major challenges for Nanoscience and Nanotechnology in Health for sustainability.(Univesidsad Tecnológica Nacional., 2022) Anunziata , Oscar AlfredoThis paper covers the physicochemical basis of studies of the structure and properties of inorganic and organic nanomaterials, advances in synthesis, processing, characterization and testing, design of Nano engineered materials and systems, and applications in technology, focusing on working atoms to individual atoms, anchored, deposited or grafted onto Carbon nanotubes and Mesoporous Carbons Keywords” “Nano Materials“,“Nanoscience“ and “Nanotechnology“,“H2 Uptake”, “Water purification“, “Drug Delivery“, ”Atom by Atom”, “Hole Electrons”