Continuity and change at C.B.C. : an ethnography of a Catholic Brothers School in Australian society

This thesis is an ethnographic investigation of a Catholic Brothers school, Christian Brothers College (C.B.C.), in the provincial city of Newburyport, Australia* The study explores the traditions and historical purposes of education at the independent, religious school, and examines the manner in which these have changed or are changing. All names, including the name of the school and the city, have been altered to preserve anonymity. The opening section discusses the emergence of the theoretical problem of the dialectic of change and continuity in the ongoing activity of C.B.C. actors. This is followed by an argument that an understanding of such activity requires an ethnographic perspective. Such a perspective, however, must not overlook the organisational and structural constraints within which participants operate. Hence, a critical ethnography, which takes account of both the agency of human actors and the structures which influence their activity, is advocated as the most suitable approach for understanding continuity and change within a complex organisation in its social context. This argument is followed by an ethnographic account of Christian Brothers College, which focuses on the perceptions and activities of teachers and administrators, Individual chapters deal with the Christian Brothers Order and its educational mission at C.B.C.; the nature of religious education at the school; the administration of the school; approaches to control and discipline; the curriculum and evaluation of pupils; and the relationship between C.B.C. and the wider Newburyport community. The concluding section integrates an analysis of continuity and change at C.B.C. with a discussion of theoretical perspectives on reproduction and transformation. The thesis concludes that, although change has occurred in many ways, an institutionalised image of C.B.C. as 'Brothers’ school'persists and impedes the formation of more democratic authority relations, curriculum, and evaluation. The potential for such change, however, is seen most strongly in the ongoing reform of religious education.

Study in Roman-Maccabaean relations

[No Abstract]

Grain boundary segregation in Fe-Mn-C twinning-induced plasticity steels studied by correlative electron backscatter diffraction and atom probe tomography

We report on the characterization of grain boundary (GB) segregation in an Fe-28Mn-0.3C (wt.%) twinning-induced plasticity (TWIP) steel. After recrystallization of this steel for 24 h at 700 °C, ∼50% general grain boundaries (GBs) and ∼35% Σ3 annealing twin boundaries were observed (others were high-order Σ and low-angle GBs). The segregation of B, C and P and traces of Si and Cu were detected at the general GB by atom probe tomography (APT) and quantified using ladder diagrams. In the case of the Σ3 coherent annealing twin, it was necessary to first locate the position of the boundary by density analysis of the atom probe data, then small amounts of B, Si and P segregation and, surprisingly, depletion of C were detected. The concentration of Mn was constant across the interface for both boundary types. The depletion of C at the annealing twin is explained by a local change in the stacking sequence at the boundary, creating a local hexagonal close-packed structure with low C solubility. This finding raises the question of whether segregation/depletion also occurs at Σ3 deformation twin boundaries in high-Mn TWIP steels. Consequently, a previously published APT dataset of the Fe-22Mn-0.6C alloy system, containing a high density of deformation twins due to 30% tensile deformation at room temperature, was reinvestigated using the same analysis routine as for the annealing twin. Although crystallographically identical to the annealing twin, no evidence of segregation or depletion was found at the deformation twins, owing to the lack of mobility of solutes during twin formation at room temperature.

Microstructure and hardness characterisation of laser coatings produced with a mixture of AISI 420 stainless steel and Fe-C-Cr-Nb-B-Mo steel alloy powders

Fe-C-Cr-Nb-B-Mo alloy powder and AISI 420 SS powder are deposited using laser cladding to increase the hardness for wear resistant applications. Mixtures from 0 to 100 wt.% were evaluated to understand the effect on the elemental composition, microstructure, phases, and microhardness. The mixture of carbon, boron and niobium in the Fe-C-Cr-Nb-B-Mo alloy powder introduces complex carbides into a Fe-based matrix of AISI 420 SS which increases its hardness. Hardness increased linearly with increasing Fe-C-Cr-Nb-B-Mo alloy, but substantial micro-cracking was observed in the clad layer at additions of 60 wt.% and above; related to a transition from a hypoeutectic alloy containing α-Fe/α' dendrites with an (Fe,Cr)2B and γ-Fe eutectic to primary and continuous carbo-borides M2B (where M represents Fe and Cr) and M23(B,C)6 carbides (where M represents Fe, Cr, Mo) with MC particles (where M represents Nb and Mo). The highest average hardness, for an alloy without micro-cracking, of 952 HV was observed in a 40 wt.% alloy. High stress abrasive scratch testing was conducted on all alloys at various loads (500, 1500, 2500 N). Alloy content was found to have a strong effect on the wear mode and the abrasive wear rate, and the presence of micro-cracks was detrimental to abrasive wear resistance.

Nucleation sites for ultrafine ferrite produced by deformation of austenite during single-pass strip rolling

An austenitic Ni-30 wt pct Fe alloy, with a stacking-fault energy and deformation characteristics similar to those of austenitic low-carbon steel at elevated temperatures, has been used to examine the defect substructure within austenite deformed by single-pass strip rolling and to identify those features most likely to provide sites for intragranular nucleation of ultrafine ferrite in steels. Samples of this alloy and a 0.095 wt pct C-1.58Mn-0.22Si-0.27Mo steel have been hot rolled and cooled under similar conditions, and the resulting microstructures were compared using transmission electron microscopy (TEM), electron diffraction, and X-ray diffraction. Following a single rolling pass of ∼40 pct reduction of a 2mm strip at 800 °C, three microstructural zones were identified throughout its thickness. The surface zone (of 0.1 to 0.4 mm in depth) within the steel comprised a uniform microstructure of ultrafine ferrite, while the equivalent zone of a Ni-30Fe alloy contained a network of dislocation cells, with an average diameter of 0.5 to 1.0 &micro;m. The scale and distribution and, thus, nucleation density of the ferrite grains formed in the steel were consistent with the formation of individual ferrite nuclei on cell boundaries within the austenite. In the transition zone, 0.3 to 0.5 mm below the surface of the steel strip, discrete polygonal ferrite grains were observed to form in parallel, and closely spaced “rafts” traversing individual grains of austenite. Based on observations of the equivalent zone of the rolled Ni-30Fe alloy, the ferrite distribution could be correlated with planar defects in the form of intragranular microshear bands formed within the deformed austenite during rolling. Within the central zone of the steel strip, a bainitic microstructure, typical of that observed after conventional hot rolling of this steel, was observed following air cooling. In this region of the rolled Ni-30Fe alloy, a network of microbands was observed, typical of material deformed under plane-strain conditions. <br />

Embodied energy in buildings : wood versus concrete - reply to Börjesson and Gustavsson

We analyse the wood and concrete designs of the Wälludden building described by B&ouml;rjesson et al. (Energy Policy 28 (2000) 575) in terms of their embodied energy, employing an environmentally extended input–output framework in a tiered hybrid life-cycle assessment, and in a structural path analysis. We illustrate the complexity of the inter-industry supply chains underlying the upstream energy requirements for the building options, and demonstrate that higher-order inputs are difficult to capture in a conventional process analysis. Our calculations show that B&ouml;rjesson and Gustavsson's estimates of energy requirements and greenhouse gas emissions are underestimated by a factor of about 2, and that corresponding greenhouse gas balances are positive at about 30 t C-eq. Nevertheless, B&ouml;rjesson and Gustavsson's general result—the concrete-framed building causing higher emissions—still holds.<br />

The production of ultrafine ferrite during hot torsion testing of a 0.11 Wt Pct C steel

Ultrafine ferrite grain sizes were produced in a 0.11C-1.6Mn-0.2Si steel by torsion testing isothermally at 675 °C after air cooling from 1250 °C. The ferrite was observed to form intragranularly beyond a von Mises equivalent tensile strain of approximately 0.7 to 0.8 and the number fraction of intragranular ferrite grains continued to increase as the strain level increased. Ferrite nucleated to form parallel and closely spaced linear arrays or “rafts” of many discrete ultrafine ferrite grains. It is shown that ferrite nucleates during deformation on defects developed within the austenite parallel to the macroscopic shear direction (i.e., dynamic strain-induced transformation). A model austenitic Ni-30Fe alloy was used to study the substructure developed in the austenite under similar test conditions as that used to induce intragranular ferrite in the steel. It is shown that the most prevalent features developed during testing are microbands. It is proposed that high-energy jogged regions surrounding intersecting microbands provide potential sites for ferrite nucleation at lower strains, while at higher strains, the walls of the microbands may also act as nucleation sites.<br />

Synthesis and reactivity of para-substituted benzoylmethyltellurium(II and IV) compounds: observation of intermolecular C-H-O hydrogen bonding in the crystal structure of (p-MeOC6H4COCH2)2TeBr2

Bis(p-substituted benzoylmethyl)tellurium dibromides, (p-YC<sub>6b>Hb>4b>COCHb>2b>)b>2b>TeBrb>2b>, (y=H (<b>1ab>), Me (<b>1b</b>), MeO (<b>1c</b>)) can be prepared<br />either by direct insertion of elemental Te across CRf-Br bonds (where C<sub>Rfb> refers to α-carbon of a functionalized organic moiety) or by the oxidative addition of bromine to (p-YC<sub>6b>Hb>4b>COCHb>2b>)b>2b>Te (y = H (<b>2ab>), Me (<b>2b</b>), MeO (<b>2c</b>)). Bis(p-substituted benzoylmethyl)tellurium dichlorides, (p-YC<sub>6b>Hb>4b>COCHb>2b>)b>2b>TeCh (y = H (<b>3ab>), Me (<b>3b</b>), MeO (<b>3c</b>)), are prepared by the reaction of the bis(p-substituted benzoylmethyl)tellurides <b>2ab><b>--c b>with S0b>2b>Clb>2b>, whereas the corresponding diiodides (p-YC<sub>6b>Hb>4b>COCHb>2b>)b>2b>Teh (y = H<br />(<b>4ab>), Me (<b>4b</b>), MeO (<b>4c</b>)) can be obtained by the metathetical reaction of <b>la--c</b> with KI, or alternatively, by the oxidative addition of<br />iodine to <b>2a--c</b>. The reaction of <b>2a--c</b> with allyl bromide affords the diorganotellurium dibrornides <b>la--c</b>, rather than the expected<br />triorganotelluronium bromides. Compounds 1-4 were characterized by elemental analyses, IR spectroscopy, ¹H, ^l3C and ¹²⁵Te<br />NMR spectroscopy (solution and solid-state) and in case of Ie also by X-ray crystallography. (p-MeOC<sub>6b>Hb>4b>COCHb>2b>)b>2b>TeBrb>2b> (<b>1c</b>) provides, a rare example, among organotellurium compounds, of a supramolecular architecture, where C-H-O hydrogen bonds appear to be the non-covalent intermolecular associative force that dominates the crystal packing.<br />

Prevalence of the thioamide {···H-N-C=S}2 synthon-solid-state (X-ray crystallography), solution (NMR) and gas-phase (theoretical) structures of O-methyl-N-aryl-thiocarbamides

Structural investigations, i.e. solid-state (X-ray), solution (¹H NMR) and gas-phase (theoretical), on molecules with the general formula MeOC(S)N(H)C<sub>6b>Hb>4b>-4-Y: Y = H (<b>1b>), NOb>2b> (<b>2b>), C(O)Me (<b>3b>), Cl (<b>4b>) have shown a general preference for the adoption of an E-conformation about the central C&ndash;N bond. Such a conformation allows for the formation of a dimeric hydrogen-bonded {H–N–C=S}b>2b> synthon as the building block. In the cases of<b> 1–3b>, additional C&ndash;H^...O interactions give rise to the formation of tapes of varying topology. A theoretical analysis shows that the preference for the E-conformation is about the same as the crystal packing stabilisation energy and consistent with this, the compound with Y = C(O)OMe, (<b>5b>), adopts a Z-conformation in the solid-state that facilitates the formation of N–H^...O, C&ndash;H^...O and C&ndash;H^...S interactions, leading to a layer structure. Global crystal packing considerations are shown to be imperative in dictating the conformational form of molecules <b>1–5b>.<br />

Structural characterization of rare intramolecularly (1,4-Te· · ·N) bonded diorganotellurides and their monomeric complexes with mercury(II) halides: metal assisted C-H· · ·X (Hg) interactions leading to supramolecular architecture

Monomeric tellurides 4-RC<sub>6b>Hb>4b>(SB)Te [SB = 2-(4,4'-N0b>2b>C<sub>6b>Hb>4b>CH=NC<sub>6b>Hb>3b>-Me); R = H, 1<b>ab>; Me,1<b>b</b>; OMe, 1<b>c</b>], which incidentally represent the first example of a telluride with 1,4-Te···N intramolecular interaction, have been prepared and characterized by solution and solid-state ¹²⁵Te NMR, ¹³C NMR and X-ray crystallography. Interplay of weak C-H···O and C-H-··π{ interactions in the crystal lattice of 1<b>b</b> and1<b>c</b> are responsible for the formation of supramolecular motifs. These tellurides undergo expected oxidative addition reactions with halogens and interhalogens and also interact coordinatively with mercury(II) halides to give 1:2 complexes, HgXb>2b>[4-RC<sub>6b>Hb>4b>(SB)Te]b>2b> (X = CI, R = H, <b>2ab>; Me, <b>2b</b>; OMe, <b>2c</b> and X = Br, R = H, <b>3ab>; Me, <b>3b</b>; and OMe, <b>3c</b>) with no sign of Te-C bond cleavage, as has been reported for some 1,5-Te·· ·N(O) intramolecularly bonded tellurides. The complexes <b>2ab> and <b>3c</b> are the first structurally characterized monomeric 1:2 adducts of mercury(II) halides with Te ligands. The 1,4-Te···N intramolecular interactions in the solid-state are retained in the complexes highlighting simultaneously the Lewis acid and base character of the Te(lI) atom. Packing of molecules in the crystal lattice of <b>2ab><br />and <b>3c b>reveals that non-covalent C-H· . ·Cl/Br interactions involving metal-bound halogen atoms possess significant directionality and in<br />combination with coordinative covalent interactions may be of potential use in creating inorganic supramolecular synthons.<br />