Polycristalline Ti oxide this films were prepared by reactive DC magnetron sputtering of Ti in O2+Ar onto Indium Tin Oxide (ITO) coated glass. Rutile and anatase phase films were obtained by heating the substrate during the deposition. Incident photon-to-current efficiency (IPCE) was studied as a function of several sputtering prameters such as temperature of the substraate, film thickness, and O2/Ar. The IPCE increased as the crystallinity of Ti oxide was systematically varied from amorphous to a mixture of anatase and rutile, and it was also enhanced in films deposited at low O2/Ar ratios. The photoresponse was measured using a three-electrode set-up with an electrolyte consisting of an aqueous 0.1 M KI solution purged with nitrogen. Action spectra were scanned between 280 and 400 nm in wavelength. The photogenerate current was found to be highly dependent on the composition thickness,...

Esta tesis se dedica básicamente a la caracterización estructural y foto electroquímica de películas de óxido de titanio depositadas por la técnica de "sputtering", con el objetivo de explorar sus aplicaciones en células solares sensibilizadas. La sensibilización de las películas de óxido de titanio se llevó a cabo mediante el empleo de un colorante denominado comúnmente como N3, que es una molécula compleja de Ru que posee un gran coeficiente de absorción en el rango visible. La caracterización de las películas de óxido de titanio se realizó mediante estudios de microscopía electrónica de transmisión (TEM), microscopía electrónica de barrido (SEM), microscopía de fuerza atómica, difracción de rayos X (XRD) y espectroscopia infrarroja (IR). Las películas mostraron una microestructura especial que se denominó "peniforme". Las propiedades estructurales mostraron...

Electrochromic nickel and nickel oxide thin films were obtained using the pyrolytic sputtering technique. The nickel oxide films were obtained in two ways. One using alcoholic solutions of Ni(NO3)26H2O, and the other using aqueous  solutions Ni(NO3)26H2O with the addition of small amounts of Co(NO3)26H2O.The deposition temperature for both cases was 300°C. Both show pronounced electrochromism; particularly in the second case when the Ni(NO3)2: Co(NO3)2 ratio is 90:10 a 50% change of transmittance is obtained in the visible range.Tungsten-phosphorus oxide films were obtained from a WOx sol to which phosphoric acid was added. The sol was prepared by ion exchange of Na2WO4.2H2O in a strongly acidic resin. The deposition temperature was 430°C. A significant increase in the loading capacity of WOx was observed as the proportion of P in the film increases.

En la presente tesis se obtienen películas de óxido de Ti por la técnica de DC sputtering (llamado en castellano evaporación catódica reactiva) para ser empleadas como electrodos de trabajo en celdas solares sensibilizadas por colorante. Las películas fueron sensibilizadas con la molécula cis-ditiocianato-bis(2,2´-bipiridil-4,4´dicarboxilato) rutenio II, que hasta el momento es el compuesto más utilizado para el uso de este tipo de nuevas celdas solares. Las películas de óxido de titanio fueron caracterizadas por microscopía electrónica de barrido, de fuerza atómica y se determinó la correlación del espesor con la rugosidad de estas, así como su dependencia con el área disponible para la interacción con la molécula del colorante sensibilizador. Las características fotoelectroquímicas de las celdas solares se evaluaron por técnicas como la medición de la eficienci...

An appropriate treatment of the problems that people, living in high Andean rural areas, have during the winter months with their cold houses, passes through a correct bioclimatic approach. This is demonstrated with the involvement of the Centre for Renewable Energy and the Faculty of Science of the National University of Engineering (UNI) in San Francisco de Raymina community (SFR) in Ayacucho. In this community a bioclimatic house has been built, allowing a thermal comfort of the occupants. This work has been done applying clearly and correctly bioclimatic concepts, some of which are presented in this article, as well as part of the experience of UNI in SFR community.

El objetivo del presente trabajo es evaluar experimentalmente el desempeño térmico de un Módulo Experimental de Vivienda (MEV), construido en la región Alto Andina, mediante la evaluación sistemática de doce configuraciones de operatividad diferentes, desde el manejo nocturno de contraventanas hasta actividad humana, uso de cocinas a gas y uso de dos sistemas de calefacción solar activos. Este objetivo se fundamenta en las mediciones de temperatura y humedad, considerando la primera como el parámetro principal de análisis térmico para verificar el desempeño térmico del MEV mediante la variación de la temperatura interior respecto al exterior, según la configuración del MEV dado a que la variación entre la temperatura diaria promedio interior y exterior muestra la eficacia de las estrategias de calentamiento o enfriamiento. En base a ello, los incrementos de temperatura en...

The present research is based on the study of the thermal comfort of the residents of the Minor Population Center of Kallapuma located at 4258 meters above sea level in the district of Tarata, province and region of Tacna. To evaluate the environmental parameters, satisfaction surveys were applied taking into account clothing, nutrition, physical activity and thermal comfort. Likewise, a device called TSVR was used that allowed measuring temperature, relative humidity, perceptions of comfort such as thermal sensation, personal information and clothing worn by the user, called thermal sensation vote (VST). These measurements were taken in the months of May, June and July of 2022. The real acceptability of thermal conditions to users was analyzed. Once the data was obtained, the neutrality temperature and thermal comfort ranges for the population of the Minor Population Center of Kallapuma...

This article aims to evaluate the thermal behavior of a construction system consisting of fired red clay brick walls with cavities, commonly used in large cities in Peru and increasingly adopted in high-altitude Andean areas without being evaluated for frost climates. Consequently, an experimental module was constructed at a real scale at 4500 masl. The experimentation carried out over 49 days shows that the thermal delay and decrement factor are 4 hours and 0.27, respectively, with the daily hourly average thermal amplitude indoors being 6.4°C and outdoors being 17.1°C. Additionally, the numerical study using EnergyPlus software and the implementation of the equivalent model of a set of homogeneous layers for heterogeneous materials, which dynamically considers the heat transfer modes by conduction, convection, and radiation, achieve good agreements of the indoor temperature between t...

El objetivo del presente trabajo es evaluar experimentalmente el desempeño térmico de un Módulo Experimental de Vivienda (MEV), construido en la región Alto Andina, mediante la evaluación sistemática de doce configuraciones de operatividad diferentes, desde el manejo nocturno de contraventanas hasta actividad humana, uso de cocinas a gas y uso de dos sistemas de calefacción solar activos. Este objetivo se fundamenta en las mediciones de temperatura y humedad, considerando la primera como el parámetro principal de análisis térmico para verificar el desempeño térmico del MEV mediante la variación de la temperatura interior respecto al exterior, según la configuración del MEV dado a que la variación entre la temperatura diaria promedio interior y exterior muestra la eficacia de las estrategias de calentamiento o enfriamiento. En base a ello, los incrementos de temperatura en...

  Zinc peroxide (ZnO2) nanoparticles were synthesized by sol-gel technique. The chemicals used for the synthesis were zinc acetate di-hydrate (Zn(CH3COO)2.2H2O) and hydrogen peroxide (H2O2) at 30% under UV radiation. The structure of the ZnO2 nanoparticles was characterized by X-ray diffraction. While the morphology and the cluster size, were determined using scanning electron microscopy. For a preliminary evaluation of the bactericidal properties of the ZnO2, the material was exposed to Bacillus subtilis (ATCC 6051), Escherichia coli (ATCC 25922) y Staphylococcus aureus (ATCC 25923) and it was found that the material has notorious antibacterial activity. 

In the present work, the energy demand is simulated for an experimental housing module built in the village of Imata, Peru, located at 4500 masl. Prior, the temperature measurements and the energy calculations necessary to validate the simulation model with the program EnergyPlus were performed. To maintain a neutral temperature of 12 ° C in July and 15 °C in December, the simulation indicated that 3,54 MWh are needed yearly, with a daily maximum of 11 kWh in July and a daily minimum of 8,4 kWh in December (monthly averages).

This paper analyzes the different thermal and dynamic energy contributions of the different proposals for modifications made in the envelopes of two experimental housing modules built in the town of Imata, Arequipa at 4519 meters above sea level. The modules were built with constructive characteristics of the place and typical design, later modifications were made such as changing the roof covering material, plastering the adobe walls with plaster, placing skylights on the ceiling and false ceiling, insulation of the false ceiling, and construction of a greenhouse attached to one of the modules. The data recording consisted of measuring the indoor air temperature of the modules and attached greenhouse, in addition to the outdoor meteorological data recording using a Davis station located at the top of the Imata municipality. The average daily indoor air temperature of the module without ...

In recent decades sandwich composites have taken a greater share in the construction industry, due to their low cost and properties that characterize these composites. Among the most important properties of these, the thermal conductivity stands out, which is directly linked to the individual's thermal comfort in a building. Currently, the Peruvian State has been developing projects in the fight against frost and cold, where one of the main interventions focuses on the construction of sustainable homes that can help the high Andean population cope with the inclement cold. In this sense, it is necessary to have construction materials appropriate for the climatic conditions of the place, and that is where lies the importance of this research. This paper proposes the study of thermal conductivity at temperature conditions close to 0 ºC of sandwich composites formed from monolithic material...

Activated carbons were prepared from corncob and red mombin seed and impregnated with chitosan. Field Emission Scanning Microscopy (FESEM) micrographs confirm the presence of chitosan in the activated carbon surface. Adsorptive and antibacterial properties of the prepared materials were compared with two adsorbents used in commercial water filters. Equilibrium adsorption experiments showed that the materials prepared in this study had maximum adsorption capacity to methylene blue that is comparable with those of the commercial adsorbents (between 145 and 192 mg/g). Activated carbons impregnated with chitosan exhibited higher antibacterial capacity against E. coli than the commercial adsorbents. The activated carbons prepared from corncob reach levels of reduction as higher as 96,3%. Meanwhile the commercial activated carbons had reduction values lower than 60,3%.

Zinc peroxide (ZnO2 ) nanoparticles were synthesized by sol-gel method and characterized structurally and morphologically. The synthesized nanoparticles were suspended in aqueous medium to functionalize cotton textile fabrics, getting textiles with antimicrobial properties. The functionalization was by impregnation process over dry woven, making use of equipment called impregnation Padder. The impregnated textile samples were microbiologically analyzed against Pseudomonas aeruginosa (ATCC 10145) and Escherichia coli (ATCC 25922) strains. Subsequently, fastness control, physical properties studies and color control analysis were performed over the textiles. We concluded that the textiles functionalized with ZnO2 nanoparticles have antimicrobial properties, moreover, physical properties and textile fastness are not affected after the functionalization process.