Wehave investigated the uncertainty in the ionization and recombination rates for iron and its impact on the derivation of the iron elemental abundance fromX-ray emission spectra. Most uncertainty is found in the dielectronic recombination rates for iron ions with L-shell outer electrons. The quantitative effect of this uncertainty on the derivation of the iron abundance depends on the spectral...

The use of a radioactive check device containing Strontium 90 was investigated to carry out the redundancy checks of Farmer-type ionization chambers. It was not possible to meet the recommended tolerance limits of the redundancy checks without taking into account the angular response of the ionization chambers. The ionization chambers exhibited a maximum variation of 1% in the angular response ...

An experimentally attained dissociation model of C 4 Br S ++ and the effect ionization site on dicationic parent survival.

[1] We investigate streamer formation in the troposphere, in electric fields above the breakdown threshold. With fully three-dimensional particle simulations, we study the combined effect of natural background ionization and of photo-ionization on the discharge morphology. In previous investigations based on deterministic fluid models without background ionization, so-called double-headed strea...

This paper describes a newlydeveloped approach for simulating the hot electron effect of submicron LDD n-MOS devices. The conventional drift-diffusion (DD) method tends to overestimate the impact ionization rate by comparing with experimental data. In particular, divergency is frequently incurred while calculating the continuity equations inclusive of impact ionization terms. To cope with this ...

When a strong electric field is applied to nonconducting matter, narrow channels of plasma called streamers may form. Branchlike patterns of streamers have been observed in anode directed discharges. We explain a mechanism for branching as the result of a balance between the destabilizing effect of impact ionization and the stabilizing effect of electron diffusion on ionization fronts. The disp...

We have investigated the effect of several common buffers (10-mM formic acid, 10-mM ammonium acetate, and 100-mM ammonium acetate) on the ionization of a series of model compounds that are amenable to negative atmospheric pressure chemical ionization to determine the extent of ionization quenching that can occur. In addition, we have compared the sensitivity of these standard mobile phases to a...

Measuring average quantities in complex mixtures can be challenging for mass spectrometry, as it requires ionization and detection with nearly equivalent cross-section for all components, minimal matrix effect, and suppressed signal from fragments and aggregates. Fragments and aggregates are particularly troublesome for complex mixtures, where they can be incorrectly assigned as parent ions. He...

Several hundred million volts per centimetre of electric-field strength are required to field-ionize gas species. Such fields are produced on sharp metallic tips under a bias of a few kilovolts. Here, we show that field ionization is possible at dramatically lower fields on semiconductor nanomaterials containing surface states, particularly with metal-catalysed whiskers grown on silicon nanowir...