Degradation of Phenol, Benzene and Cyanides in an Innovative Semi- industrial Ozonation Pilot Plant: The Effects of Operating Parameters

International audienc

Straightforward nano patterning on optical fiber for sensors development

A simple method to prepare a nano pattern along the surface of an optical fiber is applied in this Letter to develop a pH sensor. The template is made of a block copolymer that defines specific locations where gold nano particles are adsorbed on forming clusters. The average diameter of the resulting agglomerates is 121 nm, and the mean distance between the centers is 182 nm. The morphology of the gold cluster array produces localized surface plasmon resonance. The absorbance spectrum is affected by pH variations, and the ratio between the absorption at two different wavelengths is used to characterize the response, which is repetitive and reversible. This Letter highlights the potentiality of this type of chemical nano patterning for the development of optical fiber sensors.Agencia Estatal de Investigación; Ministerio de Economía y Competitividad (TEC2016-79367-C2-2-R); Government of Navarra (PI035 BINACS)

Diagnóstico operativo empresarial de la Planta de Ácido Sulfúrico y Oxígeno de Southern Perú Copper Corporation

El diagnóstico operativo empresarial para las plantas de ácido sulfúrico y oxígeno de Southern Perú Copper Corporation que se expone en la presente tesis, se genera como posibilidad de implementar mejoras operativas y de gestión en su cadena productiva y en consistencia a sus proyecciones de expansión operativa en producción de cobre y en creación de valor. El esquema de la tesis describe en un principio las características de la empresa y de las plantas de ácido sulfúrico y oxígeno en el proceso de fundición de cobre. Se describen y analizan la ubicación y dimensionamiento de estas plantas, el planeamiento y diseño de sus procesos y productos. Luego se evaluan los esquema de gestión en logística, costos, calidad, mantenimiento y la cadena de suministro para luego proponer opciones de mejora orientadas al incremento de rentabilidad operativa, ahorro en costos y propuesta de optimización en la cadena de valor para satisfacción de los clientes interno y externo. Se propone el incremento en la linea de producción de ácido sulfúrico sustentada a partir de las proyecciones de consumo interno y de exportación y basados en la existente capacidad ociosa de las plantas. Las propuestas de mejora incluyen aspectos de optimización en los procesos y recursos que permitan mantener la calidad del producto, la reducción de periodos improductivos según cambios en los diseños y características de los circuitos de plantas e incremento en la eficiencia en el capital humano en contribución a la generación de ahorros en costos fijos y variables. La contribución en rentabilidad de las plantas de ácido sulfúrico y oxígeno en el proceso de fundición se proyectan en incremento de beneficios económicos y ahorros proyectados en US$16.99 millones que representa el 20.5proyectadas por la compañía para el período 2018 y 2019 considerando una inversión de US$ 2.23 millonesThe business operating diagnosis for the sulfuric acid and oxygen plants of Southern Peru Copper Corporation exposed in this thesis, is based mainly as a possibility of implementing operational and managerial improvements as part of its productive chain. All projections maintains consistency to the company projections in copper operational expansion and value creating. The structure of the thesis describes initially the characteristics of the company and the acid sulfuric and oxygen plants as part of the copper smelter process. Description and analysis about the location and size of the plants and the planning and design of the processes and products is being addressed. In following chapters, the evaluation includes current logistics, costs, quality, maintenance and the supply chain management for proposing improvements with focus in increasing profitability in production, cost savings and proposals for value-adding chain for internal and external customer satisfaction. An increase in sulfuric acid production is proposed supported by internal consumption and exportation future projections of the product and based on existing idle capacity of the plants. The improvements includes optimization in the processes and resources driven by maintaining quality of the product, reduction of unproductive periods after modifying the designs and circuits of the plants and finally optimizing the human resources contributing to reduction in fixed and variable costs. Contribution to profitability of the acid sulfuric and oxygen plants within the smelting process includes economic returns and saving in US$16.99 million that represents about 20.5investment in US$ 2.23 millionTesi

Development of a FTIR sensor for monitoring and modelling an anaerobic dechlorinating bioreactor

Doctorat en sciences agronomiques et ingénierie biologique - UCL, 199

Resolution of mixtures of fluorophores in biological media using fluorescence spectroscopy and Monte Carlo simulation

International audienceIn excitation–emission fluorescence spectroscopy, the simultaneousquantitative prediction and qualitative resolution of mixturesof fluorophores using chemometrics is a major challenge becauseof the scattering and reabsorption effects (turbidity) presentedmainly in biomaterials. The measured fluorescence spectra aredistorted by multiple scattering and reabsorption events in thesurrounding medium, thereby diminishing the performance of thecommonly used three-way resolution methods such as parallelfactor (PARAFAC) analysis or multivariate curve resolutionalternatingleast squares (MCR-ALS). In this work we show thatspectral loadings and concentration profiles from model mixturesprovided using PARAFAC and MCR-ALS are severely distorted byreabsorption and scattering phenomena, although both models fitrather well the experimental data in terms of percentage of theexplained variance. The method to correct the fluorescenceexcitation–emission matrix (EEM) consisted in measuring theoptical properties (absorption parameter la , scattering parameterls, and anisotropy factor g) of samples and calculating thecorresponding transfer function by means of the Monte Carlosimulation method. By applying this transfer function to themeasured EEM, it was possible to compensate for reabsorptionand scattering effects and to restore the ideal EEM, i.e., the EEMthat is due only to fluorophores, without distortions from theabsorbers and scatterers that are present. The PARAFAC and MCRALSdecomposition of the resulting ideal EEMs provided spectralloadings and concentration profiles that matched the true profiles

PARAFAC analysis of front-face fluorescence data: Absorption and scattering effects assessed by means of Monte Carlo simulations

International audienc

PARAFAC analysis of front-face fluorescence data: absorption and scattering effects assessed by means of Monte Carlo simulations

International audienceThree-way fluorescence data originating from mixtures of fluorophores embedded in turbid media such as biological media get strongly modulated by wavelength dependent absorption and scattering phenomena. Thus the consistent resolution and quantitative determination of the mixture becomes a difficult task. In this study two chemometric methodologies frequently used to deal with this type of data were applied to fluorescence simulated data sets qualitatively similar to those measured in biological samples: Parallel Factor Analysis (PARAFAC) that does require the fulfillment of trilinearity, and multivariate curve resolutionalternating least squares (MCR‐ALS) which decomposes the data according to a model lacking this structure. Monte Carlo simulations were used to simulate fluorescence excitation–emission matrices (EEMs) of known fluorescent mixtures under separated and simultaneous variations of the absorption parameter μa and the scattering parameter μs. PARAFAC and constrained MCR-ALS models were then fitted to the simulated data. Both algorithms failed the recover the true profiles. The results obtained with PARAFAC and MCR-ALS models are similar and the recovered profiles exhibit severe distortions due to the absorption and scattering effects. Finally, qualitative and quantitative effects of the absorption and scattering on the fluorescence data were assessed and discussed