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C Nicole

Publications and source records attributed to C Nicole.

5 recordsLinked to original sources
PubMed2002

Photoionization microscopy.

We present the first experimental results of a technique called photoionization microscopy. Photoelectrons ejected in threshold photoionization of Xe are detected in a velocity map imaging apparatus, and interferences between various trajectories by which the electron moves from the atom to the detector are observed. The structure of the interference pattern, which contains the transverse component of the electronic wave function, evolves smoothly with the excess energy above the saddle point. The main observed features are interpreted within the framework of the semiclassical approximation.

Journal Article↗
PubMed2000

Slow photoelectron imaging.

Experiments are reported on the detection of slow photoelectrons resulting from the photoionization of Xe atoms in a dc electric field by electron imaging. In the far-field photoelectron velocity distributions we can distinguish between direct and indirect ionization processes (involving long range Coulomb interactions with the Xe+ ion). Also, a new modulation of the velocity distribution is observed which cannot be explained by previously discussed mechanisms. Classical and quantum mechanical calculations are presented to support the interpretations.

Journal Article↗
PubMed1988

A direct reading method for chlorinated hydrocarbons in breath.

A direct reading method is described for the measurement of tetrachloroethylene and 1,1,1-trichloroethane in breath for concentrations ranging from 2.5 to 30 ppm. It is based on colorimetric detector tube technology and consists of a two-step procedure: 1) total breath sampling in a bag and 2) analysis of the bag's content by detector tubes for the solvent and carbon dioxide. The latter is used to take into account dead space dilution and possible hyper- or hypoventilation. The method is tested in volunteers experimentally exposed to tetrachloroethylene and 1,1,1-trichloroethane and in workers occupationally exposed to tetrachloroethylene. Its results are compared with a reference gas chromatographic method. The agreement between the methods is good, with a systematic proportional error of less than +13% for tetrachloroethylene. Repeated measurements show standard deviations ranging from 6% to 39% of the tested concentrations.

Breath Tests↗