A structural and reactivity study of lithium molybdenum nitride

This thesis describes the preparation and reactivity of lithium molybdenum nitride samples and the preparation and characterisation of the nitride precursors. It has been shown that samples containing lithium molybdenum nitride (LiMoN2) can be formed from the direct ammonolysis of lithium molybdate (Li2MoO4), although it has proved challenging to produce the nitride as a single phase material. The “LiMoN2” samples were observed to be catalytically active for ammonia synthesis in reaction with nitrogen containing feed gas (25% N2/H2). An impurity, which cannot be indentified through powder X-ray diffraction, was demonstrated to be the likely active phase in the sample. The role of ‘lattice’ nitrogen in the ammonia synthesis reaction was investigated through reactions with a feed gas with no source of nitrogen present (25% Ar/H2). It was shown that this proposed active phase will produce ammonia, in the absence of nitrogen in the feed gas. One candidate impurity that could be responsible for this anomalous activity was lithium nitride. Reactions were conducted and it was seen that lithium nitride was very active in the production of ammonia. Subsequent investigations showed that the generation of ammonia probably originates from the direct decomposition of lithium amide

Molybdenum nitrides: structural and reactivity studies

This thesis describes the preparation, structure and activity of a range of binary, ternary and quaternary molybdenum nitrides. It has been shown that all of the samples analysed can be formed through the reaction of the respective molybdate precursor with either ammonia or 3:1 H2/N2 gas mixture. The structures of the nitrides have been studied in detail. These structural findings were then linked to the activity potential of the materials to act as stores of activated nitrogen. The main body of work focused on the ternary molybdenum nitrides of cobalt, iron and nickel with a view to understanding their differences and similarities. Full structural analysis was performed using powder X-ray diffraction (PXRD) and neutron diffraction (PND). The activity of the nitrides was examined by reaction with 3:1 H2/N2 and with 3:1 H2/Ar at various temperatures. Particular attention was paid to the reactivity of lattice nitrogen. The cobalt molybdenum nitride was shown to be special case in this regard where the nitrogen is mobile and relocates within the lattice to a different crystallographic site. This mobility and relocation is concomitant with the loss of 50% of the lattice nitrogen from the system resulting in a phase change from Co3Mo3N to the unprecedented Co6Mo6N phase. The physical and chemical properties of this novel phase have been fully characterised and studied. Interestingly, the isostructual Fe3Mo3N behaves differently and the nitrogen remains fixed and the structure and stoichiometry constant throughout the testing procedure. Further studies of the ternary molybdenum nitrides extended to nickel molybdenum nitride, which was shown to be the least active when tested under both gas mixtures, and analogously to the iron molybdenum nitride the nitrogen is fixed within the β-Mn structured nitride. Further investigations were undertaken, resulting in the successful formation of a series of quaternary nitrides (Fe3-xCoxMo3N). These materials show properties similar to the Co-Mo-N system when the material is cobalt rich and behave similarly to the Fe-Mo-N system when iron rich

BEYOND LINEARITY AND INDEPENDENCE

This brief lecture discusses statistical problems associated with postulating and fitting models in engineering and the sciences. Particular emphasis is placed on the two-model problem: the employment of both deterministic and stochastic components within a model. Further, the use of empirical versus theoretical models on the part of both statisticians and experimenters is examined

Errors and Discrepancies in Measurement of Tooth Size

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66948/2/10.1177_00220345600390022301.pd

Transforming Business Education: 21st Century Sustainable MBA Programs

Business education should give students the skills to solve complex global challenges. It should align management practices with goals for a sustainable future. Sadly, few management schools even discuss the real issues business leaders face today. This article challenges others to develop a curriculum that embeds sustainability in the core of their programs. The authors argue that faculty and business school leadership should move beyond “saddlebag” initiatives that bolt sustainability onto the traditional, shareholder primacy-driven core. This article profiles three programs as case studies transforming business education to prepare leaders to achieve a more sustainable world. Business schools are torn between competing paradigms. Given the existential challenges facing humanity, business schools will have to change or simply lose relevancy. Our stories of disruption give evidence of success and hope for the coming transformation of business education and of capitalism itself. The lessons learned and insights in this article provide guidance for business school leaders aspiring to redefine management for global sustainability and business school programs. It is an open invitation for others to disrupt and rethink business education before it is too late

Transforming Business Education: 21st Century Sustainable MBA Programs

Business education should give students the skills to solve complex global challenges. It should align management practices with goals for a sustainable future. Sadly, few management schools even discuss the real issues business leaders face today. This article challenges others to develop a curriculum that embeds sustainability in the core of their programs. The authors argue that faculty and business school leadership should move beyond “saddlebag” initiatives that bolt sustainability onto the traditional, shareholder primacy-driven core. This article profiles three programs as case studies transforming business education to prepare leaders to achieve a more sustainable world. Business schools are torn between competing paradigms. Given the existential challenges facing humanity, business schools will have to change or simply lose relevancy. Our stories of disruption give evidence of success and hope for the coming transformation of business education and of capitalism itself. The lessons learned and insights in this article provide guidance for business school leaders aspiring to redefine management for global sustainability and business school programs. It is an open invitation for others to disrupt and rethink business education before it is too late

The immunobiology of human hepatic gamma delta T cells

The liver contains a number of tissue-associated lymphocyte populations, of which many have been implicated in the pathogenesis of chronic liver diseases. $\gamma\delta$ T cells, particularly the $V\delta2^{neg}$ subset, are known to comprise a substantial proportion of tissue-associated lymphocytes, although their immunobiology remains poorly understood. Here, the localisation, TCR diversity, immunophenotype and function of human intrahepatic $\gamma\delta$ T cells was explored with an emphasis on highlighting any potential role in chronic liver disease and also to further understanding of tissue-associated $\gamma\delta$ T cells, using the liver as a model tissue. Intrahepatic $\gamma\delta$ T cells were predominantly localised in the sinusoids and did not increase in frequency with chronic inflammation. $V\delta2^{neg}$ cells exhibited private TCR clonal focussing, with complex CDR3 regions suggestive of antigen-driven expansions, concordant with a loss of naive-like $CD27^{hi}$ cells present in the periphery. Expanded clonotypes were phenotypically $T_{EM}$- or $T_{EMRA}$-like, with $T_{EMRA}$-like clonotypes shared between liver and blood and resembling vasculature-associated virus-specific $CD8^+$ T cells while $T_{EM}$ clonotypes were identified only in the liver and resembled tissue-resident $CD8^+$ T cells. These findings suggest that disease has minimal impact on intrahepatic $\gamma\delta$ T cells, while supporting an adaptive paradigm for these cells in the formation of tissue-associated subsets

Computer Storage and Retrieval System for Two-Dimensional Outlines

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/67260/2/10.1177_00220345700490053201.pd

Tooth size and approximal decay in human teeth

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/33371/1/0000769.pd

The vertical dimensions of the face and skeletodental retrognathism

This study deals with nine vertical dimensions in skeletodental retrognathism. Twenty-five boys and twenty-five girls, 11 years of age, with Class II molar relationships and ANB angles of 4.5 degrees or greater, were compared with twelve girls and thirteen boys, 11 years of age, with Class I molar relationships and ANB angles of less than 4.5 degrees.The vertical dimensions used were found to be significantly larger in the boys than in the girls. The vertical position of the mandible and palatal portion of the maxilla was not found to be different in retrognathism, but there appeared to be a slight tendency for the maxillary dentoalveolar height to be greater in retrognathism than in orthognathism. On the other hand, in these samples, there was no difference between retrognathism and orthognathism in anteroposterior position of the maxillary dentition relative to sella. A significant difference was found between samples for both sexes in the mandible, which was found to be smaller and more posteriorly positioned in retrognathism than in orthognathism. It was observed that the mandibular plane angle is slightly larger in retrognathism than orthognathism. However, the size of the mandibular plane angle appears to be related only slightly to the severity of the retrognathism.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/33394/1/0000794.pd