Publications by authors named "Radu Lazau"

Industry represents a fundamental component of modern society, with the generation of massive amounts of industrial waste being the inevitable result of development activities in recent years. Red mud is an industrial waste generated during alumina production using the Bayer process of refining bauxite ore. It is a highly alkaline waste due to the incomplete removal of NaOH.

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Bismuth oxides were synthesized from bismuth carbonate using the sol-gel method. Studies have described the formation of BiO, as a precursor of HNO dissolution, and intermediate oxides, such as BiO when using HSO and HPO. The average size of the crystallite calculated from Scherrer's formula ranged from 9 to 19 nm, according to X-ray diffraction.

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Adsorption recovery of precious metals on a variety of solid substrates has steadily gained increased attention in recent years. Special attention was paid to the studies on the characterization of the adsorptive properties of materials with a high affinity for gold depending on the nature of the pendant groups present in the structure of the material. The aim of the present work was to synthesize and characterize a new material by using the sol-gel synthesis method (designated as BCb/CB).

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This study deals with SrAlO: Eu, Dy phosphor pigments prepared by an optimized perchlorate-assisted combustion synthesis and tested for developing glow-in-the-dark safety markings. Recipes with different oxidizer/fuel ratios were designed to create an in-situ reducing-reaction atmosphere and promote Eu → Eu reduction, which is responsible for the specific long-lasting, green emission of the pigments. The obtained data proved the efficiency of glycine-rich mixtures (up to 200% glycine excess), which led to improved optical features, as compared to the reference stoichiometric sample.

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Palladium is a noble metal of the platinum group metals (PGMs) with a high value and major industrial applications. Due to the scarce palladium resources, researchers' attention is currently focused on Pd ions recovery from secondary sources. Regarding the recovery process from aqueous solutions, many methods were studied, amongst which adsorption process gained a special attention due to its clear advantages.

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The aim of this study is the rapid detection of food pressed oils adulteration with their refined versions, using UV-Vis spectroscopy. The study investigates some common oil physico-chemical parameters such are: density, viscosity, refractive index, acid index, peroxide value, saponification index, to detect differences between cold pressed oils versus refined ones, for some food-grade oils found on Romanian market, as well as FT-IR spectroscopy and GC-MS analytical method, obtaining similar results to those presented in the literature data. The difference between some of the obtained results is not relevant for telling the cold-pressed oils from their refined version for adulteration investigation purpose.

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The solution combustion synthesis of strontium aluminate, SrAl2O4, via the classic single-fuel approach and the modern fuel-mixture approach was investigated in relation to the synthesis conditions, powder properties and thermodynamic aspects. The single-fuel approach (urea or glycine) did not yield SrAl2O4 directly from the combustion reaction. The absence of SrAl2O4 was explained by the low amount of energy released during the combustion process, in spite of the highly negative values of the standard enthalpy of reaction and standard Gibbs free energy.

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