Thesis (Ph.D.)--University of Nebraska-Lincoln, 2009. / Title from title screen (site viewed February 25, 2010). PDF text: viii, 102 p. : ill. ; 1 Mb. UMI publication number: AAT 3386557. Includes bibliographical references. Also available in microfilm and microfiche formats.

Thesis (M.S.)--University of Missouri, School of Mines and Metallurgy, 1922. / The entire thesis text is included in file. Typescript. Title from title screen of thesis/dissertation PDF file (viewed April 8, 2010)

Thesis (M.S.)--West Virginia University, 2002. / Title from document title page. Document formatted into pages; contains x, 114 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 42-45).

Thesis (M. Eng.)(Metallurgical)--University of Pretoria, 2008. / Summaries in Afrikaans and English. Includes bibliographical references.

M.Ing. / In this study it is shown that numerical analysis, and more specifically computational fluid dynamics can be used to investigate, compare, predict and design lining/cooling system combinations for blast furnaces’ in order to ensure longer campaign life and better performance. Three currently available cooling systems namely, copper staves are investigated. These combined with four different refractory materials, namely high alumina, silicon carbide, semi-graphite and graphite, stated in order of increasing thermal conductivity.

Masters of Science / A nitrile and amide hydrolysing Nesterenkonia sp. was isolated from Antarctic soil and was characterised as a psychrotolerant, halotolerant and alkaliphilic extremophile. Amidases are widely distributed in both prokaryotic and eukaryotic organisms. These enzymes hydrolyze C-N bonds other than peptide bonds and are particularly interesting for their potential industrial application. This study aimed to identify and characterize amidase genes from this novel psychrotolerant microorganism. Using BLAST analysis, two ORFs with conserved amidase sequences were identified from the complete genome sequence of the organism. Two ORFs, AmiF and AmiS, were assigned to two different gene families, the aceta/formamidase family and amidase signature family, respectively. On the genome, the spatial orientation and intergenic distance (1bp overlap) of the ORF‟s suggested that amiF and amiS could possibly be cotranscribed which was confirmed by reverse transcription PCR. A third ORF with a conserved amidase sequence was found ±500bps downstream from amiS, suggesting the possible presence of a multi amidase operon. The two genes were cloned and expressed as N-terminal 6x His-Tag fusion proteins. AmiS and Ami F were partially purified using Ni-chelation chromatography. Although both proteins were subjected to activity assay, their activities are yet to be established. Homology modeling of the AmiF and AmiS translated sequences showed that the proteins had the significant similarities to the members of their families. Although the sequence identities between the AmiF and AmiS and their templates were very low (24 % and 25% respectively), the evaluation of the models showed that the quality of the models were good. This study reports the genetic and functional characterisation of amidase genes from the cold adapted microorganisms. / South Africa

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Explosives place large demands on the lateral load carrying capacity of structures. If these loads are applied on columns, the high pressure transient loads from explosives can result in significant damage to the primary gravity load carrying elements. The loss of these elements, which are responsible from overall strength and stability of the structure, may cause collapse of all or parts of the structure. Therefore, it is important to mitigate the blast loads effects on columns. A comprehensive research study into the design, application, and use of different retrofit systems to mitigate damage to columns under blast loads has been undertaken. This research program, consisting of experimental testing and analytical investigation, sought out retrofits that address the strength of columns as well as those that enhance ductility are explored. Different materials and resistance mechanisms are used to increase column capacity. An experimental testing program was conducted using a shock tube to test the capacity of columns under blast loads. For this program, a total of sixteen reinforced concrete columns were constructed and the data from a further two columns from a previous study was compiled. Of these columns, a total of thirteen were retrofitted to mitigate the effects of blast. Carbon fibre reinforced polymer (CFRP) was applied to eight of the columns in the form of jacketing, longitudinal reinforcement, or the combination of the two. The other retrofits included steel prestressed confinement applied to one column, steel bracing acting as compression members applied to one column, and steel bracing acting as tension members applied to three columns. The columns were tested under incrementally increasing shock tube induced shock wave loading up to failure of the specimen or capacity of the shock tube. The performance of the retrofitted columns was compared with the control columns and against other retrofits. Quantitative comparisons of displacements and strains were made along with qualitative assessments of damage. The results indicated that all the retrofits increased capacity to the column, however, certain retrofits out performed others. The best FRP retrofit technique was found to be the combination of longitudinal and transverse FRP. The prestressed steel jacketing proved to be effective at increasing ductility capacity of the column. The compression brace retrofit was found to be effective in significantly increasing capacity of the column. The tension brace retrofits had the best performance over all the retrofits including the compression brace retrofit. The experimental data was used to validate analysis techniques to model the behaviour of the specimens. This technique reduced the columns to an equivalent single-degree-of-freedom (SDOF) system for dynamic analysis purposes. The reduction to the SDOF system was achieved by computing a resistance to lateral load and lateral displacement relationship. Each retrofit was carefully considered in this analysis including the retrofit’s possible effect on material and sectional properties as well as any force resistance mechanism that the retrofit introduces. The results of the modeling and experimental program were used to develop retrofit design guidelines. These guidelines are presented in detail in this thesis.

Blast risk associated with terrorist threats and accidental explosions has become an international concern over the past decade and has provoked structural engineers to implement protective design measures. Recent advances in this area of research has seen tremendous improvements in mitigating this risk through the installation of retrofits, advanced structural design, or pre-emptive protective measures. Tilt-up and precast panel walls are constructed using a unique approach in which the walls are cast horizontally and lifted, or tilted, into their final vertical position. These unique structures are cost effective, energy efficient, and can be rapidly constructed. This approach is commonly applied to the construction of large industrial facilities and the construction of schools which are categorized as high importance structures in the National Building Code of Canada. These panels are inherently flexible and have a surplus of mass making them desirable for protective design applications, however their behaviour under blast induced loads is not well defined. This experimental research project investigates the behaviour of non-composite tilt-up sandwich (NCTS) panels and solid reinforced concrete (SRC) panels with realistic support conditions subjected to blast-induced shockwaves. Previous research shows that NCTS panels, identifiable by their large structural wythe, exhibit some degree of composite behaviour and require between 5% to 10% composite action for successful erection. Five scaled specimens were constructed following common procedures used in practice, equipped with identical data acquisition instruments, and tested at the University of Ottawa shock tube testing facility under similar blast pressure-impulse combinations. Test results for the NCTS and SRC panels are compared graphically in terms of displacement–time histories and sectional strain distributions. The data is evaluated to approximate the composite behaviour at mid-span of the NCTS panel. Analytical results generated, using “RC Blast,” single-degree-of-freedom analysis software developed at the University of Ottawa, were validated with empirical data and are presented graphically. Each specimen was equipped with connections similar to those commonly used in the construction of NCTS panels. These connections were experimentally studied under simulated blast pressures and analysed using CSA A23.3-04 guidelines for punching shear capacity. Modified support iii | P a g e reinforcement layouts and surface bonded FRP laminates were evaluated as strengthening and retrofit techniques to prevent support failure. Dynamic support reactions and predicted support resistances are tabulated for each shot of every panel. The results indicate that it is possible to accurately predict the flexural behaviour and support resistance of a NCTS panel using RC Blast and CSA A23.3-04 guidelines. Several factors considered in this analysis include boundary conditions, dynamic material properties, and shear tie degradation. This analysis of flexural behaviour is highly dependent on shear stiffness, which is directly related to the composite action within NCTS panels. Support resistance was increased significantly through application of the strengthening techniques outlined in this thesis.

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