RESUMO
In this work we demonstrate efficient quality control of a variety of gasoline and ethanol (gasohol) blends using a multimode interference (MMI) fiber sensor. The operational principle relies on the fact that the addition of ethanol to the gasohol blend reduces the refractive index (RI) of the gasoline. Since MMI sensors are capable of detecting small RI changes, the ethanol content of the gasohol blend is easily determined by tracking the MMI peak wavelength response. Gasohol blends with ethanol contents ranging from 0% to 50% has been clearly identified using this device, which provides a linear response with a maximum sensitivity of 0.270 nm/% EtOH. The sensor can also distinguish when water incorporated in the blend has exceeded the maximum volume tolerated by the gasohol blend, which is responsible for phase separation of the ethanol and gasoline and could cause serious engine failures. Since the MMI sensor is straightforward to fabricate and does not require any special coating it is a cost effective solution for real time and in-situ monitoring of the quality of gasohol blends.
RESUMO
The asymmetric unit of the title compound, [NiCl(2)(C(19)H(9)F(6)N(3))], contains one half-mol-ecule residing on a crystallographic twofold rotation axis. The title compound crystallizes in space group C2/c while the previously reported polymorph was reported in P2(1)/c [Baldovino-Pantaleón et al. (2006 â¶). Adv. Synth. Catal.348, 236-242]. The Ni(2+) ion exhibits a penta-coordinate distorted trigonal-bipyramidal NiCl(2)N(3) geometry, with two Cl atoms in the equatorial plane. In the crystal, mol-ecules are linked by inter-molecular C-Fâ¯π [Fâ¯centroid = 2.9676â (14)â Å] inter-actions.
