Determination of plasticity following deformation and welding of austenitic stainless steel

Intergranular strain has been associated with high-temperature cracking of welded pipework in 316H austenitic stainless steel material used in nuclear power plant heat exchangers. In this study, neutron diffraction has been used to study the development of intergranular strains in plastically-deformed and welded 316H stainless steel. Measurements have been made of the intergranular strain evolution with increasing plastic strain in base material, and correlated with further measurements made in samples extracted from welded pipes, where the pipes were welded following plastic deformation to different levels of plastic strain. Strong tensile strain evolution was seen on the compliant 200 grain family. The results were correlated with various proxy measures of plastic strain, including hardness and diffraction peak width, and excellent agreement was obtained

J. S. Bach\u27s Modal Compositional Practice in the Chorale Preludes for Solo Organ: A Schenkerian Perspective

This dissertation proposes a Schenkerian perspective of J. S. Bach’s modal compositional practice in his chorale preludes for solo organ. It develops two major themes: first, a viable framework for reconciling Schenker’s theory of tonality with the kind of composition that Bach’s modal music exemplifies (chapter 3); and second, a definition of Bach’s modal compositional practice in the chorale preludes as revealed through analysis of the repertoire (chapter 4). Additionally, the dissertation explores the pertinence of traditional modal theory to Bach’s modal music (chapter 1), confronts Schenker’s evaluation of modal composition (chapter 1), and responds to other scholarly work in this area (chapter 2). In advancing a Schenkerian interpretation of Bach’s modal compositional practice, my approach aims to reconcile rather than to adapt. Instead of altering Schenkerian theory or offering an exclusively tonal view of Bach’s modal music, I define a space within Schenkerian theory that can accommodate this repertoire. I remain faithful to the principles of Schenkerian theory but stretch their scope beyond the borders of tonality. To accomplish this, I argue that the Ursatz is best understood as an abstract prototype of tonality, and I elaborate Matthew Brown’s expression of Schenkerian theory as a set of law-like generalizations of tonal contrapuntal and harmonic behaviour. Rather than adopting an a priori idea of modality, I define Bach’s modal compositional practice by the musical behaviour that the chorale preludes exhibit as revealed in analysis and through the Schenkerian perspective. To this end, I offer original analyses of five modal chorale preludes: “Ach Herr, mich armen Sünder,” BWV 742, from the Neumeister collection; “Nun komm, der Heiden Heiland,” BWV 599, “Lob sei dem allmächtigen Gott,” BWV 602, and “Komm, Gott Schöpfer, heiliger Geist,” BWV 631, from the Orgelbüchlein; and “Kyrie, Gott Vater in Ewigkeit,” BWV 669, from Klavierübung III. I show that in the modal chorale preludes, despite the multiplicity of available options, Bach uses only seven distinct background patterns divided among three modal categories. The musical content of these modal backgrounds and the tonal behaviour of the foreground and middleground structural levels define Bach’s modal compositional practice

A Comparison of the resolution obtainable from photomechanical and electrostatic plates

This thesis addressed the question of what level of resolution was obtainable from the electrostatic plate. Resolution was defined as the ability of a material to record fine detail. Two types of plates were compared, one photomechanical and the other an electrostatic. The photomechanical plate consisted of a light sensitive coating applied to an aluminum1 base . The electrostatic plate consisted of a fused toner image on an aluminum base. The intent of this research was to determine the final resolution, not the forces and factors which effected it. The hypothesis stated that the resulting resolution of the electrostatic plate will be lower than that of the photo mechanical plate. This research addressed the following questions; What minimum and maximum percent dot, and maximum screen ruling could the plate produce