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F J Real

Publications and source records attributed to F J Real.

7 recordsLinked to original sources
PubMed2001

The role of hydroxyl radicals for the decomposition of p-hydroxy phenylacetic acid in aqueous solutions.

The chemical decomposition of p-hydroxyphenylacetic acid, a priority phenolic pollutant present in wastewaters from some agro-industrial plants, is studied by means of a single photochemical process produced by a polychromatic UV radiation and by hydroxyl radicals generated by the combination of UV radiation plus hydrogen peroxide and by the Fenton's reagent (hydrogen peroxide plus ferrous salts). Batch experiments were conducted to establish the degradation levels obtained and the quantum yields in the single photodecomposition process. An improvement in the decomposition of the phenolic acid in the combined UV/H2O2 oxidation is observed, due to the generation of OH radicals, and the contribution of the radical reaction to the global process is determined. In the Fenton's reagent oxidation, the effects of the operating variables (H2O2 and Fe2+ initial concentrations, pH, type of buffer used) are established and the rate constant for the reaction of p-hydroxyphenylacetic acid with OH radicals is evaluated from a kinetic model, its value being 7.02 x 10(8) M-1 s-1 at 20 degrees C.

Hydrogen Peroxide↗
PubMed2001

Degradation of p-hydroxyphenylacetic acid by photoassisted Fenton reaction.

The chemical decomposition of p-hydroxyphenylacetic acid, a phenolic pollutant present in agro-industrial plant effluents, has been investigated by means of the Fenton's reaction and the photoassisted Fenton's reaction, the so-called photo-Fenton system. The degradation levels achieved have been compared to those obtained by applying other Advanced Oxidation Processes, such as the combination UV/H2O2. The optimum pH to carry out the decomposition of this organic compound by either Fenton or photo-Fenton systems was found to be pH = 3. The presence of buffers such as phosphate impedes these processes due to the formation of ferric complexes. A reaction mechanism, which allows calculating the contribution of the radical reaction to the global process, has been proposed. According to this mechanism, the dominant way of degradation of p-hydroxyphenylacetic acid is through its reaction with the OH radicals originated in the photolysis of H2O2 and, especially, in the Fenton's reaction.

Carcinogens↗
PubMed1982

Anti-golgi complex autoantibodies in a patient with Sjögren syndrome and lymphoma.

During routine immunofluorescence studies of the serum of a patient with Sjögren's syndrome and lymphoma we detected antibodies giving a cytoplasmic pattern which did not correspond to previously described patterns found for autoantibodies. Using different cells and tissues as substrates for indirect immunofluorescence, including rat liver, rat small bowel, rat testicle, human thyroid, guinea-pig plasma cells and cultured human fibroblasts, the cytoplasmic structure to which these autoantibodies are directed seems to be the golgi complex, a conclusion supported by histochemical studies. Furthermore, these antibodies were absorbed by isolated golgi vesicles. The autoantibodies are of IgG and IgA classes, and the antigen(s) with which they react is(are) resistant to treatment with DNAse and RNAse. None of the sera from 50 normal individuals, seven patients with Sjögren's syndrome (five of them primary and two associated with rheumatoid arthritis; none of them with lymphoma), 25 patients with mixed connective tissue disease, 10 patients with systemic lupus erythematosus and five patients with progressive systemic sclerosis, had antibodies directed against this cytoplasmic specificity, as determined by indirect immunofluorescence. This is the first time that autoantibodies directed to the golgi complex are reported. The significance of this finding awaits further descriptions in patients with a clinical picture similar to the one reported here.

Adult↗