This paper shows that it is possible to estimate, from a single interferogram image, the error of the concave shape for an optically polished surface that will be used as a mirror in a reflecting telescope. In the Optics Laboratory of the PUCP, a Twyman-Green interferometer has been implemented; surface images with overlapping interference fringes known as interferograms are acquired. Algorithms based on Fourier transform allows the reconstruction of the surface shape and its deviation from ideal concave shape. Images were evaluated for different numbers of interference fringes in the same surface; in each case, a single image was necessary to determine surface error with the added advantage of not having contact with the surface.

En el país se dispone de una vasta cantidad de objetos arqueológicos y de arte, de los que se precisa conocer, su origen, procedencia y composición, permitiendo con ello la posibilidad de acceder a la información de gran valor artístico e histórico. El proyecto implementa una herramienta de análisis, basada en LIBS (Espectrometría de Ruptura Inducida por Laser) para ser empleada en el reconocimiento de pigmentos sobre obras de arte y la caracterización de materiales culturales arqueológicos e históricos.

New block copolymers (typ AB) were obtained by the ring opening cationic polymerization of2-cyclopropyl- and 2-methoxycarbonylethyl-2-oxazoline, using tosylated polyethylenglycolas initiator. In block copolymers, the polymerization grade of polyethylenglycol (PEG)segment was always 45 units and of the poly(2-oxazolines) segment was variable, between33 to 242 units. The block copolymers, containing 2-methoxycarbonylethyl-2-oxazoline,were submitted to a quantitative hydrólisis of ester groups to obtain carboxylic acid units.The copolymers were characterized structurally by nuclear magnetic resonance spectroscopyand they show a conformational transition (LCST) between 24 and 48°C, which was functionof the polymer structure, of its content of cyclopropyloxazoline and carboxilic acid groups.