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L-shell x-ray production cross sections have been measured for thin targets of 29Cu, 32Ge, 37Rb, 38Sr, and 39Y. M-shell x-ray production cross sections have been measured for thin targets of 79Au, 82Pb, 83Bi, 90Th, and 92U. All targets were irradiated with a beam of H+ ions with energies in a range from 70 to 200 keV. Experimental cross sections are compared to other measurements at higher energies and to first Born (Plane Wave Born Approximation for direct ionization and Oppenheimer-Brinkman-Kramers-Nikolaev approximation for electron capture) and the ECPSSR (Energy loss, Coulomb deflection, Perturbed Stationary State calculations with Relativistic effects) theoretical cross sections.

Thesis; Thesis information not provided; 1 Feb 2003. / Published through the Information Bridge: DOE Scientific and Technical Information. "JLAB-PHY-03-39" "DOE/ER/40150-2763" Silvia Niccolai. 02/01/2003. Report is also available in paper and microfiche from NTIS.

Thesis (Ph.D.); Submitted to the Massachusetts Inst. of Tech., Cambridge, MA (US); 1 Oct 2003. / Published through the Information Bridge: DOE Scientific and Technical Information. "JLAB-PHY-03-174" "DOE/ER/40150-2571" Zhengwei Chai. 10/01/2003. Report is also available in paper and microfiche from NTIS.

The purpose of this work was to examine the effect of the use the assumption κω2K/ΕCM «1 in calculating K-shell ionization cross sections in the plane wave Born approximation (PWBA) where κω2K is the observed binding energy of the K-shell and ECM is the energy of the incident particle in the center of mass system. Avoiding this assumption produces a threshold for ionization at Ecm = κω2K. Calculations employing the assumption, which leads to the use of approximate limits of integration, do not go to zero for even the .Lowest values of the incident energy.

Typescript (photocopy). / Digitized by Kansas Correctional Industries

While worker flow analysis has grown in importance in many countries, Austria still lacks a specific longitudinal dataset as a prerequisite to perform similar analyses. For this reason, this article provides a coherent procedure to construct a longitudinal dataset based on the rotational panel structure of the Austrian quarterly LFS from 2004 to 2014. The procedure, which is available for researcher, is grounded on the discussion of several related and important issues inherent in constructing this sort of longitudinal data: First, it deals with the construction of the quarterly-matched dataset and the quality-of-measurement of several labour market variables. Second, the paper analyses non-response as a sample selection process, and shows that the selected (quarterly-matched) dataset causes biased estimates of worker flows. Third, the article proposes an iterative raking procedure to obtain survey weights as a bias-correcting device for any future analysis. Based on these adjustments, we present unbiased time-series of worker flows and transition rates, and conclude that the employment-unemployment margin is highly sensitive to economic shocks and that the Austrian labour market is additionally shaped by large movements within the participation margin. (authors' abstract) / Series: Department of Economics Working Paper Series

Thesis (MSc)--Stellenbosch University, 2000. / ENGLISH ABSTRACT: The aim of this work was to study the 208Pb(p,2p)207Tl quasi-free knockout process. The experimental data were measured at the National Accelerator Centre using incident polarised protons of 200 MeV. The two scattered particles, from the knockout reaction, were detected in coincidence and their energies were determined using a magnetic spectrometer and a solid state detector telescope. Cross section and analysing power energy distributions were extracted from the experimental measurements and these were compared with theoretical values for the Distorted Wave Impulse Approximation. The theoretical cross-section calculations predict the experimental cross-section distribution well for all combinations of distorting potentials and bound states that were investigated, both with regard to shape, as well as absolute magnitude. However the theoretical analysing power distributions did not agree with the experimental quantities. Therefore it is not clear whether the analysing power is a useful tool to extract information on the specifics of the quasi-free reaction mechanism. The spectroscopic factors were found to be consistent with the results obtained in previous studies, thereby inspiring confidence that the problem with the analysing power distribution is not ascribable to a possible deficiency in the experimental techniques exploited in this work. / AFRIKAANSE OPSOMMING: Die doel van die studie was om die kwasi vrye 208pb(p,2p )207TI verstrooingsproses te ondersoek. Die eksperimentele data is ingewin by die Nasionale Versnellingsentrum deur gebruik te maak van 'n 200 MeV gepolariseerde proton bundel. Die twee verstrooide deeltjies is in koïnsidens gemeet. Vir die metings is 'n magnetiese spektrometer en 'n vastetoestand detektorteleskoop gebruik. Die kansvlak- en analiseervermoë-energieverdelings is uit die eksperimentele data verkry en is vergelyk met die berekenings van die Vervormde Golf Impuls Benadering. Die teoretiese kansvlak berekening het die eksperimetele data goed voorspel, vir die verskillende parametrisering van potensiaal en gebonde toestande. Die berekeninge het goed ooreengestem met betrekking tot beide vorm en absolute grootheid. Die berekende analiseervermoë het egter nie goed met die eksperimentele data ooreengestem nie. Dit is dus nie duidelik of die analiseervermoë 'n handige instrument is om inligting oor die betrokke kwasi-vrye reaksie meganisme te bekom nie. Die spektroskopiese faktore was in ooreenstemming met resultate wat in vorige studies verkry is. Dit versterk vertroue dat die probleem met die analiseervermoë nie toegeskryf kan word aan die eksperimentele tegniek wat gebruik is nie.

Ion mobility (IM) spectrometry is a gas-phase electrophoretic technique in which ions are separated on the basis of their relative mobility in the presence of a weak electric field gradient and a buffer gas. Ion mobility-mass spectrometry (IM-MS) has the capability of separating ions based on m/z, size and shape, providing additional structural information compared to using mass spectrometry on its own. In this thesis, IM-MS has been used to investigate organic and organometallic complexes and identify reactants, intermediates and products in reaction mixtures. Collision cross sections (CCS) have been measured for three salen ligands, and their complexes with copper and zinc using travelling-wave ion mobility-mass spectrometry (TWIMS) and drift tube ion mobility-mass spectrometry (DTIMS), allowing a comparative size evaluation of the ligands and complexes. CCS measurements using TWIMS were determined using peptide and TAAH calibration standards with good intra-day and inter-day reproducibility. TWIMS measurements gave significantly larger CCS than DTIMS derived data in helium, indicating that the choice of calibration standards is important in ensuring the accuracy of TWIMS derived CCS measurements. The CCS data obtained from IM-MS measurements have been compared to CCS values obtained from X-ray coordinates and modelled structures. The analysis of small organic and organometallic molecules has been extended to investigations of the potential of IM-MS for reaction monitoring and structural studies of the components of catalytic cycles. Reaction mixtures of an organocatalysed Diels-Alder cycloaddition reaction have been monitored using IM-MS and high-field asymmetric waveform ion mobility-mass spectrometry (FAIMS-MS). Reactant, product, catalyst and reaction intermediates, including an intermediate not previously detected, were identified and the catalyst and intermediates monitored over time. An organometallic catalytic cycle using a palladium catalyst has been analysed using IM-MS and the CCS of reactants, intermediates and products have been measured and compared to theoretical CCS calculations. Good agreement was observed between measured and calculated data. Species not amenable to electrospray ionisation were covalently bound to an ionisable tag containing a quaternary ammonium ion allowing the tagged molecules to be detected by IM-MS.