Zobrazeno 1 - 10
of 17
pro vyhledávání: '"Ulrich Hoefer"'
Publikováno v:
Sensors and Actuators B: Chemical. 175:40-45
The physical mechanisms of spreading of smoke and gas during a fire event must not be necessarily the same. Due to the heat smoke particles are more likely transported by convection with a minor contribution of diffusion effects whereas gas is transp
Autor:
Christopher J. Stanton, Avinash Rustagi, Ulrich Hoefer, Andreas Beyer, Wolfgang Stolz, Hrvoje Petek, Kunie Ishioka, Kerstin Volz
Publikováno v:
International Conference on Ultrafast Phenomena.
Autor:
Wolfgang Stolz, Christopher J. Stanton, Hrvoje Petek, Kerstin Volz, Avinash Rustagi, Andreas Beyer, Ulrich Hoefer, Kunie Ishioka
We report on the optical generation and detection of ultrashort acoustic pulses that propagate in three-dimensional semiconductor crystals. Photoexcitaiton of lattice-matched GaP layers grown on Si(001) gives rise to a sharp spike in transient reflec
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::f803646945d03dce84a7c7f4f8c938e1
Publikováno v:
Procedia Engineering. 25:1121-1124
We selected a variety of low-power gas sensors in order to compare their performance with respect to fire detection applications. Gas sensitive field effect transistor (GasFET)-arrays, metal oxide sensors (MOS) and electrochemical cells (EC) were mea
Autor:
Courbat Jerome Christian, D. Gutmacher, N. F. de Rooij, Danick Briand, K. Severin, Jürgen Wöllenstein, Ulrich Hoefer, M. Pascu
Publikováno v:
Procedia Engineering. 25:1329-1332
We report on a colorimetric carbon monoxide (CO) sensor based on a rhodium complex. The sensor relies on changes in the light absorption properties of the chemochromic reagent when exposed to the gas. Its optical properties in solution and in a polym
Autor:
Ulrich Hoefer
Publikováno v:
teme. 72:646-653
Abgassensoren, die für die Verbrennungsoptimierung geeignet sind, basieren bisher meist auf der bekannten λ-Sonde aus ZrO2, wie sie in ähnlicher Art massenhaft in Kraftfahrzeugen eingesetzt wird. Für den Einsatz in anderen Verbrennungsprozessen w
Autor:
Michael Duerr, Ulrich Hoefer
Publikováno v:
ChemInform. 45
Publikováno v:
Sensors and Actuators B: Chemical. 78:6-11
High temperature Ga 2 O 3 -gas sensors show some differences to other sensors based on other metal oxides like SnO 2 . Among the advantages of Ga 2 O 3 -based sensors good long-term stability, fast response and recovery times, good reproducibility, l
Publikováno v:
Sensors and Actuators B: Chemical. 47:213-217
The conductance of a thin SnO 2 film in contact with platinum is used to detect NO 2 down to the 10 ppb range with a cross sensitivity to CO of the order of only 10 −4 . The SnO 2 layer thickness of 60 nm is chosen of the order of the depletion lay
Autor:
Ulrich Hoefer, Klaus Steiner, Gerd Kühner, Harald Böttner, Arne Dipl Phys Dr Felske, Gerd Sulz
Publikováno v:
Sensors and Actuators B: Chemical. 44:429-433
The selectivity of SnO2 thin-film gas sensors can be modulated by changing the contact areas of the contact electrodes. The investigated SnO2 arrays have been structured with two mask steps only. Gas mixture analysis in the German threshold limit val