Sensitized solar cells working electrodes of titania (TiO2) nanoparticles were modified with nickel oxide (NiO), which were synthesized from nickel chloride (NiCl2.6H2O). The deposit of the working electrode was performed by Doctor. Blade technique and the sensitization process was performed using commercial dye: Di-tetrabutylammonium cis-bis (isothiocyanato) bis (2,2'-bipyridyl-4,4 '-dicarboxylato) ruthenium (II), also known as N719. The structural and morphological characterization of the working electrodes was performed by X-ray diffraction and scanning electron microscopy, respectively. The photoelectrochemical characterization of the working electrodes and solar cells was performed by measuring the Incident Photon to Current Efficiency (IPCE) and the current-voltage, respectively. Ni concentration in the TiO2 powder was 125 ppm as determinated by atomic absorption. Efficiency m...

A prototype has been developed that could monitor the water quality in real time based on an “electronic tongue”. The system is based on electrochemical methods and involves the combination of non-selective sensors (metal electrodes), the signal processing part, and a pattern recognition. It determines attributes (quality, status of a process, etc.) rather than single parameters. Unique response patterns for liquid samples are interpreted with principal components analysis. The prototype is portable and has evaluated the water quality in a rural area (Yaurisque, Cusco). The system could discriminate water with different chemical and bacterological composition.

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Películas delgadas de óxido de zinc, fueron fabricadas por un sistema de rociado pirolítico equipado con un arreglo óptico que asegura el control in-situ del crecimiento de la película. Una solución 0,1 M de acetato de zinc diluida en una mezcla de etanol y agua, fue usada como solución precursora. La temperatura de depósito y el pH de la solución precursora fueron mantenidos a 350°C y 4,5 respectivamente. Los patrones de difracción de rayos X, revelan que las películas fueron la fase zincita con un tamaño de grano dependiente de la proporción molar etanol/agua, Г, en la solución precursora. El patrón de interferencia obtenido durante el crecimiento de la película fue usado para monitorear la rugosidad de la película; encontrándose que está relacionado con los resultados de análisis superficial y óptico obtenido por microscopía electrónica de barrido (SEM) y medi...

Zinc oxide films were fabricated by a home-made spray pyrolysis system equipped with an optical set-up ensuring the in-situ control of the film growth 0.1 M of zinc acetate diluted in a mixture of ethanol and water was used as the precursor solution. The deposition temperature and the pH of the precursor solution were kept at 350°C and 4.5, respectively. X-ray diffraction patterns revealed that films were zincite-like with a grain size depending of the ethanol/water molar ratio, Γ, in the precursor solution. The interference pattern obtained during film deposition was used to monito the film roughness: it was found that this is related with those results of surfaces and optical analysis obtained by scanning electron microscopy (SEM) and spectrophotometric measurements, respectively. Photo-electrocatalytic results indicated that there is a correlation of the partial molar volume of etha...

  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. 

El peróxido de zinc (ZnO2) fue sintetizado en forma de nanopartículas por medio de la ruta sol-gel. Para la síntesis se empleó acetato de zinc di-hidratado (Zn(CH3COO)2.2H2O) y peróxido de hidrogeno (H2O2) al 30% asistido de radiación UV. Las nanopartículas de ZnO2 obtenidas fueron caracterizadas estructuralmente mediante la técnica de difracción de rayos-X. Mientras que el estudio de la morfología y tamaño de conglomerados cristalinos, se realizó por microscopía electrónica de barrido. Para explorar las propiedades bactericidas del ZnO2, se realizaron pruebas preliminares en las que se enfrentó este material a las cepas: Bacillus subtilis (ATCC 6051), Escherichia coli (ATCC 25922) y Staphylococcus aureus (ATCC 25923), y se observó que las nanopartículas presentan una notoria propiedad bactericida.

  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. 

Textiles functionalized with cupric oxide (CuO) nanoparticles have become a promising option to prevent the spread of diseases due to their antimicrobial properties, which strongly depend on the structure and morphology of the nanoparticles and the method used for the functionalization process. This article presents a review of work focused on textiles functionalized with CuO nanoparticles, which were classified into two groups, namely, in situ and ex situ. Moreover, the analyzed bacterial strains, the resistance of the antimicrobial properties of textiles to washing processes, and their cytotoxicity were identified. Finally, the possible antimicrobial mechanisms that could develop in Gram-positive and Gram-negative bacteria were described.

El peróxido de zinc (ZnO2) fue sintetizado en forma de nanopartículas por medio de la ruta sol-gel. Para la síntesis se empleó acetato de zinc di-hidratado (Zn(CH3COO)2.2H2O) y peróxido de hidrogeno (H2O2) al 30% asistido de radiación UV. Las nanopartículas de ZnO2 obtenidas fueron caracterizadas estructuralmente mediante la técnica de difracción de rayos-X. Mientras que el estudio de la morfología y tamaño de conglomerados cristalinos, se realizó por microscopía electrónica de barrido.

Activated carbons and activated carbons modified with ZnO nanoparticles were prepared mixing agricultural wastes like corn cob or red mombin seed with the activating chemical agent, ZnCl2, in a weight ratio 1:1 or with ZnCl2 and zinc acetate in a weight ratio 1:1:0.5 in aqueous medium, respectively. Pellets were obtained from this slurry and were dried before being carbonized. The resulting material was repeatedly washed with a solution of HCl 0,5 M and abundant distilled water to finally be dried at 100°C for 12 h in the form of pellets, which were crushed and sieved to a size smaller than 0,25 mm. A Field Emission Scanning Electron Microscope was used to characterize the different morphologies of the ZnO nanoparticles on the surface of the obtained activated carbon which depended of the raw material used to produce the activated carbon, however in both samples the presence of ZnO was ...

El agua potable es un bien sumamente escaso en el mundo. De los estimados 1.4 billones de kilómetros cúbicos de agua sobre la tierra, el 97.6 % es salada, 2.38 % está como hielos y glaciares y aproximadamente solo 0.024 % se encuentra sobre la superficie terrestre y por lo tanto puede ser destinada para el consumo humano. Ante esta situación, la falta de acceso al agua potable es un problema muy serio en el mundo y el Perú no es una excepción. De los 6 billones de personas que pueblan la tierra, más de un billón sufre de este problema. Sin embargo, cerca de 2.5 billones no tienen acceso a un adecuado servicio de saneamiento. Esto se traduce en que más de 6 millones de niños por año mueren por enfermedades que tienen su origen en el agua que consumen.

The current study synthesizes some of the main contributions from recent research about the new forms and elements of heterosexual romantic relationships that individuals are adopting  uring the adolescent stage. These relationships are currently divided into formal and informal, the existence of the last ones is due to the replacement of the strict traditional environment because many changes that make up the postmodern era which, in turn, involves marked divergences in the process and content in current relationships and different areas of daily life. As a result of the analysis carried out, it is important to mention the limited existence of information about the subject and even more in the new relationships of couple in specific populations such as homosexual, indigenous or rural areas.

The current study synthesizes some of the main contributions from recent research about the new forms and elements of heterosexual romantic relationships that individuals are adopting  uring the adolescent stage. These relationships are currently divided into formal and informal, the existence of the last ones is due to the replacement of the strict traditional environment because many changes that make up the postmodern era which, in turn, involves marked divergences in the process and content in current relationships and different areas of daily life. As a result of the analysis carried out, it is important to mention the limited existence of information about the subject and even more in the new relationships of couple in specific populations such as homosexual, indigenous or rural areas.

The application of nanotechnology has gained importance in the finishing of textile products, imparting them functional properties, which are achieved without affecting the textile. A novel method was developed for the in situ growth of CuO nanoparticles (NPs) onto cotton textiles by the exhaust dyeing method. For functionalised textiles, a constant sodium hydroxide concentration (0.4 g l(-1)) and different percentages of on-weight-fabric (% owf) of copper acetate were used. The textiles were microbiologically evaluated, the laundering durability was assessed and their UV protection factor (UPF) was determined. In addition, their CIE L*a*b* colour coordinates and colour strength (K/S) were studied. The results determined that NPs on the textile were CuO and were distributed randomly on the cotton fibre surface. The functionalised textiles with CuO NPs had percentages of bacterial reducti...