Influence of the volume of ascorbic acid in the synthesis of copper nanoparticles mediated by chemical pathway and its stability over time

In the present investigation, the effect of ascorbic acid volume in the synthesis of copper nanoparticles (Cu NPs) mediated by chemical route and their stability over time was evaluated. For the synthesis, copper sulfate pentahydrate CuSO4 (5H2O) was used as a precursor agent and ascorbic acid (AA) as a reducing agent. Cu NPs was characterized by the following techniques: UV-Visible spectrophotometry to evaluate structural changes that are evidenced in the absorbance peak and atomic absorption spectrophotometry to define nanoparticulate concentrations material in the precipitated and supernatant phases generated. On the methodology it was possible to observe a controlled formation based on the increase in the volume of ascorbic acid in the presence of sodium hydroxide, noticing a production of Cu nanostructures with a tendency to oxidation over time. The UV-visible results showed characteristic surface plasmon resonance peaks of metallic copper for the colloid containing 1.2 mL of A.A; as well as a specific copper concentration of 0.14 ppm in the supernatant and 1519.1 ppm in the precipitate. It is also evidenced that the solution exhibits a rapid reaction on exposure to air by shifting the absorbance peak to 386 nm. In addition, it does not present notable photosensitivity with respect to exposure to sunlight

Reuse of organic waste from Eucalyptus globulus extract with high reducing potential in the green synthesis of silver nanoparticles

The research provides a new and sustainable methodology for the synthesis of silver nanoparticles, using Eucalyptus globulus extract, this due to the fact that it presents metabolites capable of acting as a reducing potential of our silver nitrate precursor, and thus obtaining nanostructured material. This is also associated with the reuse of this type of organic material, which currently abounds as waste in the Peruvian highlands. In the specific case of this research, the effect on the stability over time of the biosynthesized silver nanoparticles was evaluated by varying the pH, with values of 4.82, 8.05 and 10.15. It was observed that as the pH increases the production of nanoparticles is higher, having a saturation threshold close to pH 8. It was also found that for alkaline pH close to 10 a more complete reaction of the reducing agent occurs, but with a high dispersion

Ecological and sustainable synthesis of silver nanoparticles from alcoholic extract of Eucalyptus globulus: evaluation of alcoholic solvent influence (70 and 96 )

The present study provides an ecological and sustainable methodology for obtaining nanostructured material from Eucalyptus globulus leaf extract, as a potential value-added alternative and a contribution to circular economy. Silver nanoparticles (NP Ag) were synthesized, through the reducing action of the alcoholic extracts of eucalyptus on the precursor silver nitrate (AgNO3) evaluating the influence of alcoholic solvent (70 ° and 96 °) and pH in the synthesis. The silver colloids obtained were evaluated by UV-vis spectrophotometry, which shows the formation of nanoparticles through the plasmon resonance peak; showing that for pH values 9.9 and 10 with alcohol extract of 70 ° and 96 ° respectively, silver nanoparticles with plasmon resonance peaks at 410 nm and 412.5 nm are obtained. While for pH values 3.86, 11.8 (96°) and 4.7, 8.2 (70°) nanoparticles with higher polydispersity and in a lower proportion are obtained. The results suggest that the alcoholic extracts of eucalyptus can act as reducing agents and that the optimum pH value for the synthesis of silver nanoparticles corresponds to 10

Generation of Bioelectricity Using Molasses as Fuel in Microbial Fuel Cells

The large amount of molasses that are generated in sugar-processing companies are not always redistributed for commercialization in by-products. Because of this, the present research uses these wastes as fuel in low-cost, lab-scale, single-chamber microbial fuel cells. Zinc and copper electrodes were used as electrodes and 100 mL of molasse in the chamber as fuel, managing to generate current and voltage peaks of 1.73 ± 0.13 mA and 0.953 ± 0.142 V. In monitoring the conductivity of the substrate, a maximum peak of 111.156 ± 8.45 mS/cm was observed, and a slightly acidic pH was observed throughout the monitoring. It was possible to obtain a power density of 5.45 ± 0.31 W/cm2 for a current density of 308.06 mA/cm2, while the yeast count showed a logarithmic curve throughout the monitoring. Finally, the molecular technique identified 100% of the special C. boidinii present in the anodic electrode. This research will give great benefits to sugar companies because they will be able to generate electricity using the molasses that cannot generate by-products

Potential Use of Mango Waste and Microalgae Spirulina sp. for Bioelectricity Generation

Potential use of organic waste and microalgae generates bioelectricity and thereby reduces harmful effects on the environment. These residues are used due to their high content of electron-generating microorganisms. However, so far, they have not been used simultaneously. Therefore, this research uses mango waste and microalgae Spirulina sp. in double-chamber microbial fuel cells to generate bioelectricity. The cells were made at a laboratory scale using zinc and copper electrodes, achieving a maximum current and voltage of 7.5948 ± 0.3109 mA and 0.84546 ± 0.314 V, with maximum electrical conductivity of the substrate being 157.712 ± 4.56 mS/cm and an optimum operating pH being 5.016 ± 0.086. The cells showed a low internal resistance of approximately 205.056 ± 25 Ω, and a maximum power density of 657.958 ± 21.114 mW/cm2 at a current density of 4.484 A/cm2. This research provides an excellent opportunity for mango farmers and exporting and importing companies because they can use their own waste to reduce their electricity costs when this prototype is brought to a large scale

Bioelectricity through microbial fuel cells using avocado waste

The dumping of organic waste in the areas surrounding food supply centers and the excessive use of fossil fuels for energy generation have generated major pollution problems worldwide. One of the novel solutions is the use of organic waste for electricity generation through the use of microbial fuel cell technology. In this research, low-cost, laboratory-scale, doublechamber microbial fuel cells were fabricated using zinc and copper as electrodes and avocado waste as fuel. Current and voltage values of 3.7326 ± 0.05568 mA and 0.74 ± 0.02121 V were achieved on the seventh day, with an optimum operating pH of 5.98 ± 0.16 and a maximum electrical conductivity of 94.46 ± 5.12 mS/cm. The cells showed a very low operating resistance of 71.480 , indicating the good electrical conductivity of the electrodes. Likewise, a power density of 566.80 ± 13.48 mW/cm2 at a current density of 5.165 A/cm2 was generated. This research provides an eco-friendly solution to farmers and companies dedicated to the export and import of this fruit because it shows the benefits of using their own waste for the generation of electricity, reducing costs

Determinación de los parámetros de ablación de contaminantes sobre láminas OHP mediante un láser Nd:YAG y su aplicación en limpieza láser

En este trabajo se determinaron los parámetros para la limpieza por ablación láser de contaminantes depositados mediante atracción electrostática sobre sustratos de láminas de acetato de celulosa (OHP) y su análisis mediante la medición de la transmitancia de la superficie irradiada en función de la energía por pulso de un láser Nd:YAG. La energía fue controlada mediante el tiempo de retraso del Q-switch usando longitudes de onda en la región infrarroja de 1064 nm y luz visible verde de 532 nm. Se utilizó un máximo de 10 pulsos láser con una frecuencia de 1 Hz sobre lo s sustratos con contaminantes con 9 μm y 11 μm de espesor. Se encontró que para la limpieza láser sin daños de sustratos de la s láminas OHP, es conveniente usar una longitud de onda de 1064 nm, con una fluencia de 0.4 J/cm2 y usando un máximo de 6 pulsos. Se verificaron las ventajas de la radiación láser pulsada en la limpieza no destructiva de sustratos con contaminantes y el análisis de la transmitancia del sustrato en el monitoreo de los procesos de interacción láser-materia

Generation of electricity through yeast Galactomyces sp.

En la búsqueda de nuevos combustibles capaces de generar energía eléctrica de forma sostenible y amigable con el medio ambiente, esta investigación utilizó la levadura Galactomyces sp en celdas de combustible microbiana a escala de laboratorio y bajo costo, para dar una nueva solución innovadora. Las celdas de combustible microbiana se fabricaron de polietileno con electrodos de zinc y cobre como ánodo y cátodo, respectivamente. Logrando generar valores picos de corriente y voltaje en circuito abierto de 4.23033 ± 0.3102 mA y 0.7522 ± 0.03573 V, con un pH óptimo de 7.84772 ± 0.21744 y conductividad eléctrica pico del sustrato de 58.89078 ± 2.51661 mS/cm. De la misma forma , la densidad de potencia mostrada fue 4.749 ± 0.294 W/cm2 con densidad de corriente de 351.086 mA/cm2. Por último, las celdas de combustible microbiana se conectaron en serie, generando 2 .6 0 V y logrando encender un foco led verde. Dando de esta forma una nueva y un prometedor uso de esta levadura para generar electricida

Electric current generation through the Wickerhamomyces anomalus yeast

Recientemente se ha presentado gran interes por las celdas de combustible microbiana y los diferentes sustratos utilizados dentro de ella para la generación de energia electrica. Debido a esto, se ha utilizado a la levadura Wickerhamomy ces anomalus como nueva fuente de geneeracion de electricidad, est e sustrato fue identificada molecularmente con un porcentaje de 99.82.% de identidad. Con lo cual se logro generar una corriente y voltaje maximo en el novena y octavo dia de 2.6678 ±0.0981 mA y 0.823 ± 0.125 V, todo esto una conductividad electrica del sustrat o de 49.37 ± 1.12 mS/cm en el novena dia y un pH de operación de 6.32 ± 0.421en esos dias. En el mismo sentido se mostro una densidad de potencia maxima de 8.176 ± 0.855 W/cm2 para un a densidad de corriente de 362.057 mA/cm2. Estos valores demuestran el gran potencial que tiene esta levadura para la generación de corriente electrica y su nuevo uso como combustible en celdas de combustible microbiana; siendo una alternative ecoamigable para el medio ambiente

Incorporation of biosynthesized silver nanoparticles in active biodegradable films of potato starch

En este trabajo se presenta el estudio del efecto de la incorporación de nanopartículas de plata biosintetizadas sobre las propiedades de películas biodegradables fabricadas a partir de almidón de papa y comprobar su potencial para ser usado como material activo. Las nanopartículas de plata fueron fabricadas mediante ruta verde a partir de residuos de uva y fueron añadidas en el proceso de gelatinización de las películas en concentraciones de 3% y 6% v/v. Las nanopartículas de plata fueron caracterizadas mediante espectroscopía UV-Vis y FTIR, mientras que las películas fabricas fueron caracterizadas mediante su densidad y % de contenido de humedad. Las propiedades activas se caracterizaron usando cinética de absorción de agua y biodegradación por enterramiento en suelo. Se confirmó la integración de las nanopartículas de plata en películas biodegradables fabricadas a partir de almidón de papa confirmando los efectos en sus características físicas y propiedades activas en función del porcentaje de AgNp, las cuales pueden ser aprovechadas para la fabricación de materiales activos