Ionization time fixed

Equilibrium (i.e. local steady-state) ionization leads in this regime to solar-corona-like conditions where col-lisional ionization is balanced by recombination and the degree of ionization is fixed by the temperature alone, the electron density cancelling out. However, here departures from equilibrium occur because the time taken to establish ionization equilibrium is not negligible with respect to the timescale of expansion. 

AGC scan function consists of a pre-ionization segments include the steps described in the step, a fixed short ionization time related to the text. (Reprinted with permission from [5])... 

Key words Matrix-assisted laser desorption/ionization, time-of-fight, mass spectrometry, mass spectrometry imaging, formalin fixed and paraffin embedded, frozen tissue, on tissue digestion, proteins identification. 

This value of 25,000 ps is fixed by the user in the acquisition method as the maximum ionization time. It is indeed important to supply a maximum ionization time to prevent too much acquisition time when no analyte enters the trap. 

The transformation of cyclopentanol-cyclohexanone mixture was carried out in a fixed-bed reactor at 200°C and 250°C under atmospheric pressure and in the presence of nitrogen (nitrogen/reactant molar ratio = 4). The reactant was an equimolar mixture of cyclopentanol and cyclohexanone. The reaction products were analyzed on line by GC (VARIAN 3400 chromatograph, equipped with a SGE CIDEX B 25 m x 0.22 mm column and a flame ionization detector). The deactivation profile was obtained by analyzing reaction effluent for various times-on-stream (TOS). 

Figure 3. Classical phase portraits (upper panel), residual quantum wavefunctions (middle panel), and ionization probability versus time (in units of the period T) (bottom panel). The parameters are (A) F = 5.0, iv = 0.52 (B) F = 20, iv = 1.04 and (C) F = 10 and u> = 2.0. Note that the peak structure of the final wavefunction reflects both stable and unstable classical fixed points. For case C, the peaks are beginning to coalesce reflecting the approach of the single-well effective potentiai (see text). 

Actually, the kinetic study of the cluster redox potential by pulse radiolysis [31] (Section 20.3.2) somewhat mimics the process of the black-and-white photographic development, except that clusters are free in the solution (not fixed on AgBr crystals), and that they are produced by ionizing radiation (as in radiography and not by visible photons but the last choice had been incompatible with the time-resolved optical detection in the visible. Beyond the critical nuclearity, they receive electrons without delay from the developer already present (actually, the photographic development is achieved in a delayed step). 

In our experiment a sequence of two intense laser pulses is used to excite K atoms in an atomic beam from the 4.s- to the 4p state. Simultaneously, the pulses ionize the excited a-toms from the 4/7 state to the continuum via two-photon ionization (Fig. 1). Photoelectron spectra were taken at various delay times between the two laser pulses and at different laser intensities at a fixed delay time. 

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