Marcia Muller

TL;DR: In this article, the authors used etched fiber Bragg grating (FBG) to determine the thermo-optic coefficients of hydrocarbon samples, where the effective refractive index (RI) of the fundamental mode becomes dependent on the surrounding this article.

Abstract: We report the use of optical sensors based on long period gratings written in standard telecommunication fibers. Applying electrical arc discharges from a fusion splicer produces the optical devices. Results from the hydrocarbon detection in fuel, water and atmospheric environment are shown. Wavelength shifts in the long period gratings attenuation peak as longer as 10.3, 2.6, 50.6, and 6.1 nm are obtained when different concentrations of turpentine, naphtha, paint thinner, and anhydrous alcohol, respectively, are added to the commercial Brazilian gasoline blend. The exposition of long period gratings to a mixture of butane and propane in air results in a wavelength shift of 0.6 nm in the attenuation peak. In the experiments carried out in water environment, a 6 nm wavelength shift is measured in the hydrocarbon presence. These results point to the prospect of using the long period gratings sensor for fuel quality control and for the detection of hydrocarbon vapors in the air or petroleum pollutants in water environments.

TL;DR: In this paper, a long-period fiber grating transducer was employed to assess the gasoline conformity in commercial gas stations and the results showed that the developed transducers can be used to infer the ethanol?water concentration with a resolution of up to 0.23%.

TL;DR: A set of tools for metrological evaluation of optical fiber grating sensors, including uncertainty analysis of the measurements, based on the International Standard Organization's Guide to the Expression of Uncertainty in Measurement is discussed.

TL;DR: In this paper, a comparative study of the behaviour of an in-fibre Mach-Zehnder interferometer for salinity measurement in a water solution is presented.