Herr Guillermo Villena Tapia
Chemie
Biografie
Kurzbiographie
- November 2005 - Present: PhD student of Chemistry, Fachbereich C, Bergische Universität Wuppertal, Germany. Thesis Project: “Development and Application of a new Long Path Absorption Photometer (LOPAP) Instrument for Sensitive Detection of NO2”.
- September 2000 – December 2001: Post-degree studies in “Administration and Management in Environmental Studies” (PROGOA), Faculty of Engineering, Universidad de Santiago de Chile.
- March 1993 - September 2000: Chemistry and B.Sc. in Chemistry careers, Faculty of Chemistry and Biology, Universidad de Santiago de Chile. Thesis Project: "Study of Nitrites and Peroxides in Hydrometeors in Santiago City”.
Titel und Abstract des Dissertationsprojektes
Development of a new Long Path Absorption Photometer (LOPAP) Instrument for the Sensitive Detection of NO2 in the Atmosphere
(Supervisors: Prof. Dr. Peter Wiesen / Priv. Doz. Dr. Jörg Kleffmann)
A compact and simple instrument for the sensitive detection of NO2 in the atmosphere has been developed. NO2 is sampled in a stripping coil by a selective chemical reaction, converted into a highly absorbing dye, which is detected by long path absorption in a liquid core waveguide. A set of interferences was quantified in the laboratory which so far can all be neglected. The significant interferences against HONO and O3 were suppressed by using an upstream HONO/O3-scrubber. The instrument has a detection limit of 2 pptV, an accuracy of 10 % and a precision of 0.5 % for 3 min time resolution. Thus, the new NO2-LOPAP technique is more sensitive than known commercial NO2 instruments. The new analyzer is much simpler to apply than other highly sensitive and selective NO2 methods, e.g. LIF or REMPI methods. The new instrument allows an absolute calibration that can be easily performed with liquid nitrite standards, which is significant advantage compared with other NO2 measurement techniques for which NO2 calibration gas mixtures are typically necessary. The new instrument has been validated against the chemiluminescence technique during an urban field campaign and against the FTIR technique in a smog chamber under complex photosmog conditions. The data sets exhibit high correlation and excellent agreement.
Neuigkeiten
Vortragstätigkeit
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Publikationen
1. Villena G., Bejan I., Wiesen P., Kurtenbach R., Kleffmann J.: Interferences of commercial NO2 instruments under different conditions, Atmospheric Measurement Techniques, 2012, 5, 149-159.
2. Villena G., Wiesen P., Flocke F., Weinheimer A., Montzka D.,Knapp D., Hall S. R., Ullmann K., Mauldin L., Kosciuch E., McGrath J., Beine H., Staebler R.M., Kleffmann J.: Nitrous acid (HONO) during polar spring in Barrow, Alaska: A net source of OH radicals?, Journal of Geophysical Research, 2011, 116, D00R07, doi:10.1029/2011JD016643.
3. Villena G., Kleffmann J., Kurtenbach R., Wiesen P., Lissi E., Rubio M.A., Croxatto G., Rappenglück B.: Vertical Gradients of HONO, NOx and O3 in Santiago de Chile, Atmospheric Environment, 2011, 45, 3967-3873.
4. Villena G., Bejan I., Wiesen P., Kurtenbach R., Kleffmann J.: Development of a new Long Path Absorption Photometer (LOPAP) Instrument for the Sensitive Detection of NO2 in the Atmosphere, Atmospheric Measurement Techniques, 2011, 4, 1663-1676.
5. Rubio M.A., Vilches V., Lissi E., Villena G., Elshorbany Y., Kleffmann J, Kurtenbach R., Wiesen P.: Rate of nocturnal ozone depletion in downtown Santiago, Chile, Fresenius Environmental Bulletin, 2011, 20, 1277-1282.
6. Fuchs H., S. M. Ball, B. Bohn, T. Brauers, R. C. Cohen, H.-P. Dorn, W. P. Dubé, J. L. Fry, R. Häseler, U. Heitmann, R. L. Jones, J. Kleffmann,T. F. Mentel, P. Müsgen, F. Rohrer, A. W. Rollins, A. A. Ruth,A. Kiendler-Scharr, E. Schlosser, A. J. L. Shillings, R. Tillmann,R. M. Varma, D. S. Venables, G. Villena Tapia, A. Wahner, R. Wegener,P. J. Wooldridge, and S. S. Brown: Intercomparison of measurements of NO2 concentrations in the atmosphere simulation chamber SAPHIR during NO3Comp campaign, Atmospheric Measurement Techniques, 2010, 3, 21-37.
7. Elshorbany Y., Kleffmann J, Kurtenbach R., Lissi E., Rubio M., Villena G., Gramsch E., Rickard A. R., Pilling M and Wiesen P.: Seasonal dependence of the oxidation capacity of the city of Santiago de Chile, Atmospheric Environment, 2010, 44, 5383-5394.
8. Elshorbany Y., Kleffmann J, Kurtenbach R., Lissi E., Rubio M., Villena G., Gramsch E., Rickard A. R., Pilling M and Wiesen P.: Summertime Photochemical Ozone Formation in Santiago, Chile, Atmospheric Environment, 2009, 43, 6398-6407.
9. Rubio M.A., Lissi E., Villena G., Elshorbany Y., Kleffmann J., Kurtenbach R., Wiesen P.: Simultaneous measurements of Formaldehyde and Nitrous Acid in dews and gas phase in the atmosphere of Santiago, Chile, Atmospheric Environment, 2009, 43, 6106-6109.
10. Elshorbany Y., Kurtenbach R., Wiesen P, Lissi E., Rubio M., Villena G., Gramsch E., Rickard A. R., Pilling M and Kleffmann J.: Oxidation Capacity of the city air of Santiago, Chile, Atmospheric Chemistry and Physics, 2009, 9, 2257-2273.
11. Rubio M.A., Lissi E., Villena G.: Factors determining the concentration of nitrite in Santiago of Chile dews, Atmospheric Environment, 2008, 42, 7651-7656.
12. Rubio M.A., Gramsch E., Lissi E., Villena G.: Seasonal dependence of peroxyacetylnitrate (PAN) concentrations in downtown Santiago, Chile, ATMOSFERA, 2007, 20, No 4, 319-328.
13. Rubio M.A., Guerrero M.J., Villena G., Lissi E.: Hydroperoxides in dew water in downtown Santiago, Chile. A comparison with gas-phase values, Atmospheric Environment, 2006, 40, 6165-6172.
14. Rubio M.A., Lissi E., Villena G., Caroca V., Gramsch E., Ruiz A.: Estimation of Hydroxyl and Hydroperoxyl radicals concentrations in the urban atmosphere of Santiago, Journal of the Chilean Chemical Society, 2005, 50, No2, 471-475.
15. Rubio M.A., Oyola P., Gramsch E., Lissi E., Pizarro J., Villena G.: Ozone and Peroxyacetylnitrate in downtown Santiago, Chile; Atmospheric Environment, 2004, 38, 4931-4939.
16. Rubio M.A., Alvarado L., Villena G., Pizarro J., Lissi E.: Deposition, Decomposition and Stabilization of Peroxides in Santiago City Dew Waters, The Science of the Total Environment, 2003, 313, 1-3, 115-125.
17. Rubio M. A., Lissi E., Villena G.: Nitrite in rain and dew in Santiago city, Chile. Its possible impact on the early morning start of the Photochemical Smog, Atmospheric Environment, 2002, 36, 293-297.
Sonstige wissenschaftliche Aktivitäten/Mitgliedschaften
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Sonstiges
Dipl.-Chem.
