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1

Detailed spectral monitoring of different combustible blends based on gasoline, ethanol and methanol using FT-Raman spectroscopy

Ortega Clavero V., Weber A., Schröder W., Meyrueis P., Javahiraly N.

Environmental Biotechnology

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2012

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Vol. 8, No. 1

1-6

EN

The use of mixtures of oil-based fuels with organic chemical components (e.g. ethanol, methanol) has been gaining ground in recent years. Several countries try nowadays to replace part of the fossil fuels for various reasons including economics, sustainability or optimization of resources. The characteristics of these combustiblerelated chemical component blends can be analyzed by different means. Optical spectral analysis (e.g. Raman, Fourier-transforminfrared, etc.) can extract inmany casesmost of the required information concerning themolecular structure of a determined chemical sample in an effective and clean manner. Experimental detailed Raman spectra fromvarious gasoline-ethanol blends and a gasoline-ethanolmethanol blend are presented. The Raman spectral information obtained has been used for approximated quantitative analysis with no additional chemical marker or complicated calibration methods. The analysis has been performed using a self-designed, low-cost, robust and frequency precise Fourier transform Raman (FT-Raman) spectrometer. This proposed FT-Raman spectrometer has been constructed with a Michelson interferometer, an in-house designed photon counter, and a sensitive trans-impedance photo-detector. Additional complex hardware was not used to compensate the mechanical or thermal drifts disturbances in the interferometer. For accurate spectral calculation an interference pattern generated by a low-power Helium-Neon laser (wavelength λ=632.816nm)was used. The resulting spectral data are in the range of 0*cm-1 to 3500*cm-1. The resolution of these Raman spectra is 1.66*cm-1. Higher resolutions are possible since the scanning distances in the Michelson interferometer can be extended substantially before instrumental effects appear. A comparison of the experimental results obtained with standard Raman shift values revealed a satisfactory accuracy and precision in frequency detection.

2

A class of hypercyclic Volterra composition operators

Herzog G., Weber A.

Demonstratio Mathematica

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2006

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Vol. 39, nr 2

465-468

EN

We prove that certain Volterra composition operators are hypercyclic on the Frechet space of all continuous functions u : [0,1) ->- R or C with u(0) = 0.

3

Motywy Vladimira Voevodskiego

Chałupnik M., Weber A.

Roczniki Polskiego Towarzystwa Matematycznego. Seria 2: Wiadomości Matematyczne

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2003

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[Z] 39

27-38

4

Generalized Riemann-Hilbert transmission and boundary value problems, Fredholm pairs and bordisms

Bojarski B., Weber A.

Bulletin of the Polish Academy of Sciences. Mathematics

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2002

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Vol. 50, no 4

479-496

EN

We present classical and generalized Riemann-Hilbert problem in several contexts arising from K-theory and bordism theory. The language of Fredholm pairs turns out to be useful and unavoidable. We propose an abstract formulation of a notion of bordism in the context of Hilbert spaces equipped with splittings.