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CuSnS (CTS) quantum dots were synthesized by solvothermal technique with poly(vinylpyrrolidone) (PVP) as a surfactant. The structural and optical properties were studied using X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy, and UV-vis spectroscopy. The electronic band gap was measured using cyclic voltammetry. The infrared photoresponse of the CTS quantum dots-incorporated device was measured under different illumination intensities of the infrared lamp, 1550 and 1064 nm lasers. The characteristics of the photodetector device, that is, responsivity, external quantum efficiency, and specific detectivity were calculated. This study proves the potential use of CTS quantum dots in infrared photodetectors.

The Cu2SnS3 thin films were deposited using an economic, solution processible, spin coating technique. The films were found to possess a tetragonal crystal structure using X-ray diffraction. The film morphology and the particle size were determined using scanning electron microscopy. The various planes in the crystal were observed using transmission electron microscopy. The optimum band gap of 1.23 eV and a high absorption coefficient of 104 cm−1 corroborate its application as a photoactive material. The visible and infrared (IR) photo response was studied for various illumination intensities. The current increased by one order from a dark current of 0.31 μA to a current of 1.78 μA at 1.05 suns and 8.7 μA under 477.7 mW/cm2 IR illumination intensity, at 3 V applied bias. The responsivity, sensitivity, external quantum efficiency and specific detectivity were found to be 10.93 mA/W, 5.74, 2.47% and 3.47 × 1010 Jones respectively at 1.05 suns and 16.32 mA/W, 27.16, 2.53% and 5.10 × 1010 Jones respectively at 477.7 mW/cm2 IR illumination. The transient photoresponse was measured both for visible and IR illuminations.

quantum dots in the size range of 2.7 nm to 3.6 nm were synthesized using a solution based heat up method. The structural, optical and electrical properties were studied using X-ray diffraction, transmission electron microscopy, UV-Vis spectroscopy, X-ray photoelectron spectroscopy and cyclic voltammetry. In this paper we report, the infrared photo detection of Cu 2 SnS 3 quantum dots. The responsivity, external quantum efficiency and specific detectivity were measured for the infrared lamp under different applied biases and for different illumination intensities of the 1550 nm and 1064 nm lasers. The responsivity, external quantum efficiency and specific detectivity exhibited high values of 1.76 A W À1 , 272.53% and 2.79 Â 10 11 Jones at À0.5 V applied bias, under infrared lamp illumination intensity of 0.48 W cm À2 .

Características del alpechín: modelos y análisis estadístico.Presentamos una síntesis de los trabajos realizados en los últimos 50 años relacionados con la caracterización del alpechín. Realizamos una recopilación de los datos publicados, buscando correlaciones entre los datos relativos al alpechín y los compuestos fenólicos. Esto permite la determinación de las características del alpechín a partir de una sola medida: La concentración de compuestos fenólicos.Proponemos dos modelos, uno basado en datos relativos a seis países y un segundo aplicado unicamente a Portugal. El análisis estadístico de las correlaciones obtenidas indica que la demanda química de oxígeno de un determinado alpechín es una función polinómica de segundo grado de su concentración de compuestos fenólicos.Se comprobó la significancia de esta correlación mediante la aplicación del análisis multivariable ANOVA, y además se evaluó la distribución de residuos y sus promedios a un nivel de fiabilidad del 95 y 99%. Este trabajo ayudará al diseño futuro de plantas de tratamiento de alpechín, así como a su funcionamiento y control.PALABRAS-CLAVE: Características del Alpechín -Compuestos Fenólicos -Demanda Química de Oxígeno -Modelos. SUMMARY Olive mill wastewater characteristics: modelling and statistical analysis.A synthesis of the work carried out on Olive Mill Wastewater (OMW) characterisation is given, covering articles published over the last 50 years. Data on OMW characterisation found in the literature are summarised and correlations between them and with phenolic compounds content are sought. This permits the characteristics of an OMW to be estimated from one simple measurement: the phenolic compounds concentration. A model based on OMW characterisations from 6 countries was developed along with a model for Portuguese OMW. The statistical analysis of the correlations obtained indicates that the Chemical Oxygen Demand of a given OMW is a second-degree polynomial function of its phenolic compounds concentration. Tests to evaluate the significance of regressions were carried out, based on multivariable ANOVA analysis, on visual standardised residuals distribution and their means for confidence levels of 95 and 99%, clearly validating these models. This modelling work will help in the future planning, operation and monitoring of an OMW treatment plant.

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