Dry matter, crude protein and starch degradation characteristics of one corn (Pioneer 39P78) and four barley grain varieties (CDC Bold, CDC Dolly, Harrington and Valier) were evaluated in two in situ nylon bag trials. Trial 1 compared ground and rolled treatments of Harrington barley and Pioneer 39P78 corn, whereas Trial 2 evaluated ground and rolled treatments of the four barley varieties. Rumen degradability characteristics were compared with analytical results from thermal- and synchrotron-source FTIRM. Infrared absorbance spectra were collected from corn and four barley varieties using thermal-source FTIRM on the mid-IR beamline at the Canadian Light Source, Ltd. (Saskatoon, SK). Synchrotron-source FTIRM spectral data was collected for corn, Harrington barley and Valier barley on the U2B mid-IR beamline at NSLS-BNL (Upton, NY). CHO:Amide I peak area ratios were compared to the in situ rumen degradation results to determine if FTIRM spectral data could be related to the rate and extent of rumen degradation, and if thermal- and synchrotron-source FTIRM yielded different results. A grain x processing method interaction (P<0.01) was observed in both in situ trials where grinding produced a greater increase in the rate and extent of rumen degradation for Harrington barley than it did for corn (Trial 1) along with a greater increase in the rate and extent of rumen degradation for CDC Bold and CDC Dolly than for Harrington and Valier (Trial 2). Among barley varieties, increasing rate and extent of rumen degradation (CDC Bold>CDC Dolly>Harrington>Valier) corresponded to increasing starch:protein ratio as estimated by chemical analysis. This relationship was reversed for corn and Harrington barley where corn had a higher starch:protein ratio yet slower rumen degradation kinetics. For both thermal- and synchrotron-source FTIRM, CHO:amide I peak area ratios were greater (P<0.05) for corn than for Harrington barley. Comparison of CHO:amide I peak area ratios of barley varieties measured with thermal-source FTIR showed that varieties with higher (P<0.05) CHO:Amide I peak area ratios generally had higher rate and extent of rumen degradation. This indicates that starch:protein ratio estimated with FTIRM may be an indicator of rumen degradability characteristics when comparing varieties of the same grain, but not for different species of grains.

Reproduction de : Thèse de doctorat : Mécanique et matériaux : Reims : 2005. / Titre provenant de l'écran titre. Bibliogr. f.

Thèse de doctorat : Génie électrique : Vandoeuvre-les-Nancy, INPL : 2006. / Texte en anglais. Seul le chapitre 1 est en français. Titre provenant de l'écran-titre. Bibliogr.

Thesis (Ph. D.)--University of Missouri-Columbia, 2002. / Typescript. Vita. Includes bibliographical references (leaves 98-103). Also available on the Internet.

Thesis (Ph. D.)--University of Missouri-Columbia, 2002. / Typescript. Vita. Includes bibliographical references (leaves 98-103). Also available on the Internet.

Zugl.: Stuttgart, Univ., Diss., 2007.

Universiẗat, Diss., 1999--Dortmund. / Dateiformat: PDF.

Abstract In this thesis, the electronic structure of selected atoms was investigated by means of electron and uorescence spectroscopy. Synchrotron radiation was used to excitate atoms in gas phase. In particular, the photoionization and subsequent Auger decay processes in metal vapours were studied as well as the resonant Auger decay in rare gases. The experimental results were analyzed together with theoretical predictions obtained utilizing the multiconfiguration Dirac-Fock method.

This Licentiate thesis presents research accomplished at theSection of Atomic and Molecular Physics at the Royal Instituteof Technology in Stockholm using photon induced fluorescencespectroscopy (PIFS) during the last two years. The main results presented are summarized: - Neutral photodissociation in CO was observed aftersynchrotron photon excitation in the range 19-26 eV bycollecting dispersed fluorescence from excited neutral C atoms.Follow-up ab initio calculations point out CO Rydberg seriesconverging to the CO+ C and D states as precursors. - The branching ratio between N2 + (B-X)(v’=1,v’’=2) and (v’=0,v’’=1)transitions in the 20-46 eV energy range reveals strongnon-Franck-Condon effects. Ab initio calculations indicate thatthe autoionization of certain superexcited states areresponsible for some of the structures present in the branchingratio curve, confirming the important role of non-Rydbergdoubly excited resonant states (NRDERS) in de-excitationprocesses above the ionization potential. - Photon induced neutral dissociation processes in NO arereported. Neither Rydberg series nor other molecular states inNO known so far can account for the collected data. From abinitio calculations more information regarding the NO precursorstates and the mechanism behind the observed neutraldissociation were obtained. - The details of a new experimental set-up for gas phasefluorescence measurements using synchrotron radiation aredescribed. It is able to perform simultaneous measurements ofdispersed and total fluorescence in the visible range. Thefirst results obtained with this set-up are presented,concerning fluorescence after excitation of the N2 molecules inthe N 1s edge. These four studies conform the set of papers enclosed in theLicentiate thesis. Finally a pre-study to further apply PIFS to speciespreviously excited by microwave discharge is included as futureplans. / NR 20140805

Ces travaux de thèse rentrent dans le cadre de l’étude de la dynamique ultra rapide de l’aimantation. Tout d’abord sont présentés des aspects théoriques, puis les aspects expérimentaux de ces expériences. Pour ce faire, nous avons étudié la réponse d’alliages ferrimagnétiques à composition variables à l’aide d’un dispositif de mesure d’effet Kerr résolu en temps, puis dans une seconde partie, la dynamique de l’aimantation et de la bande de valence du gadolinium épitaxié sur tungstène. Dans ce cadre rentre une étude de l’oxydation de ce matériau, limitant dans le temps les études approfondies. Pour finir, il est mis l’accent sur un phénomène contraignant lors des études de dynamique électronique en photoémission, l’effet de charge-espace. Ceci a pour effet de générer des photoélectrons à partir de métaux, à l’aide d’un processus multiphotonique. Nous proposons dans cette partie un modèle théorique expliquant ce phénomène.Ces travaux sont inscrits dans le cadre du développement du synchrotron SOLEIL, pour permettre le développement du FEMTOSLICING, qui permettra prochainement de mesurer des dynamiques rapides résolues en éléments, à une résolution de l’ordre de la centaine de femtosecondes. / Those thesis works are included in the framework of the study of ultrafast magnetization dynamics. First of all I introduce theoretical aspects, then experimental aspects of this kind of experiments.In this aim, we have studied the answer of ferromagnetic alloys of different compositions with a bench of time resolved magneto optical Kerr effect measurement, then in a second part, the magnetization and valence band dynamics of the epitaxial Gadolinium on tungsten. In this framework, we studied the oxidization of the Gd, which limits in the time the studies. In the end, we focus on a disturbing process that happens during the study of electrons dynamics in photoemission, the space charge effect. This can generate photoelectrons from metals, with a multiphotonic process. We propose in this last part a theoretical model to explain this phenomenon.These works are included in the development of SOLEIL synchrotron facility, in order to allow the development of the FEMTOSLICING, that will next allow to perform element resolved experiments within a time resolution of a hundredth of femtoseconds.