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Effect of Natural Gas Fuel Addition on the Oxidation of Fuel Cell Anode Gas
Get PDFThe anode exhaust gas from a fuel cell commonly has a fuel energy density between 15 and 25% that of the fuel supply, due to the incomplete oxidation of the input fuel. This exhaust gas is subsequently oxidized (catalytically or non-catalytically), and the resultant thermal energy is often used elsewhere in the fuel cell process. Alternatively, additional fuel can be added to this stream to enhance the oxidation of the stream, for improved thermal control of the power plant, or to adjust the temperature of the exhaust gas as may be required in other specialty co-generation applications. Regardless of the application, the cost of a fuel cell system can be reduced if the exhaust gas oxidation can be accomplished through direct gas phase oxidation, rather than the usual catalytic oxidation approach. Before gas phase oxidation can be relied upon however, combustor design requirements need to be understood. The work reported here examines the issue of fuel addition, primarily as related to molten-carbonate fuel cell technology. It is shown experimentally that without proper combustor design, the addition of natural gas can readily quench the anode gas oxidation. The Chemkin software routines were used to resolve the mechanisms controlling the chemical quenching. It is found that addition of natural gas to the anode exhaust increases the amount of CH3 radicals, which reduces the concentration of H and O radicals and results in decreased rates of overall fuel oxidation
A Partial Oxidation Technique for Fuel-Cell Anode Exhaust-Gas Synthesis
Get PDFThis paper describes the performance of a gas generator used to synthesize the exhaust gas from the anode of a molten-carbonate fuel cell. The composition of this gas is estimated to be that of equilibrium at 1,250 ° F and 1 atm: 48% CO2 , 39% H2O, 5% CO, and 8% H2, with an energy content of approximately 39 Btu/scf (higher heating value). To synthesize a range of gas compositions around this point, the gas generator partially oxidizes a mixture of CH4 , O2 , and CO2 to generate energy densities between 20 and 60 Btu/scf at temperatures between 1,198 and 1,350 ° F. Results show that the technique provides a relatively high ratio of CO to H2 concentrations compared with the target composition (CO:H2 of 2, versus 0.71). A detailed chemical model shows that the likely cause is quenching of the CO and H2 chemistry below 2,000 ° F
The sense of a beginning : Bakhtinian dialogic criticism on 'the gospel' in Mark.
Get PDFContemporary literary approaches have caused paradigm shifts in Biblical Studies in the last two decades as it appears in a great deal of Markan studies using narrative, reader-response, deconstructive, feminist, and new historicist approaches. However, literary studies on the Gospel of Mark have not taken into account theoretical questions underlying those approaches. As a result biblical critics are driven by new trends without ever having a chance to examine the critical baggage of the approaches. Consequently, there is a gap of communication between the old and the new one. Therefore this thesis is an attempt to meet the need of enhancing the quality of critical endeavour in biblical studies. In the light of most recent competing critical theories of literature, the first contribution of this thesis is the methodological finding that Bakhtinian dialogic criticism contains the most profound philosophical and practical foundations for solving some crucial theoretical problems in contemporary literary theories. It is a critique to a Saussurian linguistic system of language which becomes the very foundation of modern and postmodern literary criticism. Bakhtinian literary theory shifts the foundation of literary criticism on linguistic signs into the creative activity of the socio-cultural production of human communication. The shift into socio-cultural reality of language communication makes the notion of 'genre' very important to unlock the problem of text and context in literary studies. Since the Gospel of Mark has fascinated most literary critics in Biblical Studies, the problem of 'genre' of this gospel is chosen as the focus of this study. Secondly, as no agreement is reached as to what 'genre' the Gospel of Mark belongs, this thesis makes its contribution to the discussion by locating the problem of 'genre' of Mark in the context of genre theories and argues that the Bakhtinian suggestion to find genre in the socio-cultural sphere by analysing artistic intercourse between narrative agents in Mark has freed the competing analysis from the unresolved problem between the kerygmatic (content oriented) approach and the analogical (form oriented) approach. To achieve finding 'genre' in the socio-cultural sphere, this thesis focuses on Bakhtinian analysis of the process of artistic intercourse between narrative agents. The narrative communicative interrelationships between narrative agents is constructed in this thesis as a 'stereophonic' Bakhtinian model of dialogic communication. This model is an original contribution of this thesis for revising the traditional two dimensional model of narrative communication. Based on this dialogical model of communication, a special role is given to the Bakhtinian 'author-creator' in the realization process of genre through the interaction of polyphonic voices. Through the interaction of voices of the author-artist and the hero we are led to discover a relatively stable type of portraying and controlling reality in Mark, known as the genre of Roman 'satire'. The closest literary affinity is Satyrica by Petronius. This narrative strategy of 'satire' in Mark has its root in the prophetic discourse of the Old Testament which is saturating the speech of the narrator, John the Immerser, the centurion, the people, and even Jesus. Finally, the whole search for Markan 'genre' culminates in the analysis of the realization of genre through the analysis of Bakhtinian chronotope. The reality of the genre of Mark is its social reality that is in its role as dpxrj/ 'beginning'. As the Gospel of Mark proclaims itself as 'a beginning', it defines its claim of socio-cultural 'authority' in early Christianity. It is this 'sense of beginning' which enables the narrating and the narrated world of Mark to interact dialogically
Niche pattern in a Great Basin rodent fauna
No full textNiche pattern of a desert rodent community in shrub habitats of central Utah was examined in the canonical space formed by the first four principal components of trapsite, microhabitat. Positions of species centroids differed significantly (P \u3c .05) in this space and were consistent with the known habits of each; thus, it appears that the principal components measured biologically meaningful facts. Abundance in optimal habitat (a1) increased with niche breadth (v1) and decreased with increasing difference of centroids of a species from the overall mean habitat (d1). V1 was positively related to d1. Differences between niche pattern of this community and that of deciduous forest small mammals are discussed
Polyphony and the anxiety of influence in the fiction of Henry James
Get PDFJames's fiction, especially in the Middle Phase, centres
on the figure of the artist and is characterized by, the two
interrelated aspects which previous criticism has largely
overlooked: the Bakhtinian 'polyphonic' -creation of
'author-thinkers'; and the conflict between ephebes and
precursors, for which Harold-Bloom's concept of 'the-anxiety of
influence' is the most illuminating model. Polyphony is the
narrative mode, and influence is the intra-artistic, theme.
These, as the Introduction to the thesis makes clear, are
rehearsed in James's inaugural novel, Roderick Hudson. Rowland
Mallet is an author-thinker, and his failure is caused by
authorial limitations. His monologism -is impaired by his
mistaking empathy for the authorial sympathy. Likewise,
Hudson's failure does not arise from a mercurial temperament,
but from a polyphonic shortcoming: not possessing the power of
fiction to contain the fiction of power in, his mentor. And the
relationships among the three artists - Gloriani, Hudson and
Singleton - perfectly exemplify the Bloomian-theme. It is these
two concepts, polyphony and influence, which are the major
preoccupation in the Middle Phase; as, the works chosen
demonstrate. These are a novella, a novel, and a number of
short stories all of which have been unjustifiably neglected.
Chapter One, on The Aspern Papers, argues that Tina Bordereau,
far from being, the artless victim seen by many critics,
actually challenges and defeats the narrator by the very form
of her narrative. Her 'realist' discourse undermines his
language of 'romance', and shows up its internal unstability.
Chapter Two is an extensive study of the critical reception of
The Tragic Muse. The most common areas of critical attention
have been its contemporary topicality, its relation to previous
novels on similar themes, and the possible genealogy of Gabriel
Nash. Those have all missed the core of the work. - Chapter Three
demonstrates how polyphony and the anxiety of influence make
the novel what it really is. Influence arises from the
juxtaposition of, and the wrestling between, artistic ephebes
and their precursors (Nick and Nash,, Miriam and Madame Carre).
The dialogic quality defined by Bakhtin is crucial to the
proper, and even-handed, characterization of all, the conflicts
in the novel. And since most of James's tales in the eighties
and nineties -are about 'masters - and acolytes, the anxiety of
influence remains central. Chapter Four is a study of 'The
Author of Beltraffiol' and 'The Lesson of the Master'. Again the
characters' manipulations are a crucial focus in a way that
G6rard Genette's terminology helps to illuminate. The fact that
the ephebe is the author-thinker emphasizes the inextricability
of the Bakhtinian and the Bloomian in James. Just as
polyphony offers a different focus for explicating the poetics
of James's fiction; so the ephebal conflict provides the basis
for a fresh perception of James's own artistic struggle
An Historically-Grounded Critical Analysis of Research Articles in MIS
Get PDFIn order to explore scientific writing in Information Systems (IS) journals, we adopt a combination of historical and rhetorical approaches. We first investigate the history of universities, business schools, learned societies and scientific articles. This perspective allows us to capture the legacy of scientific writing standards, which emerged in the 18th and 19th centuries. Then, we focus on two leading IS journals (EJIS and MISQ). An historical analysis of both outlets is carried out, based on data related to their creation, evolution of editorial statements, and key epistemological and methodological aspects. We also focus on argumentative strategies found in a sample of 436 abstracts from both journals. Three main logical anchorages (sometimes combined) are identified, and related to three argumentative strategies: 'deepening of knowledge', 'solving an enigma' and 'addressing a practical managerial issue'. We relate these writing norms to historical imprints of management and business studies, in particular: enigmafocused rhetorics, interest in institutionalized literature, neglect for managerially grounded rhetoric and lack of reflexivity in scientific writing. We explain this relation as a quest for academic legitimacy. Lastly, some suggestions are offered to address the discrepancies between these writing norms and more recent epistemological and theoretical stances adopted by IS researchers.argumentative strategies; history; academic writing; legitimacy
Regulation of human fibroblast insulin-like growth factor (IGF)-binding proteins by IGF-1 and cytokines, mechanisms of action and effects upon IGF bioactivity
No full textPhDThe insulin-like growth factors, IGF-I and IGF-II, are ubiquitous polypeptide molecules
that have mitogenic and metabolic actions in a wide variety of cell types, and
consequently play a major role in mammalian growth and development. Unlike many
other peptide hormones, IGF levels and their bioactivity are highly dependent upon the
secretion of a family of six specific binding proteins, named IGFBPs. In this thesis, we
have developed a normal human fibroblast in vitro cell culture model to investigate both
factors that affect IGFBP secretion, the mechanisms behind such regulation, and also the
effect of IGFBP modulation upon subsequent IGF-I mitogenic activity.
Firstly, we have examined the possible role that the recently discovered IGFBP proteases
may have in determining the effect of IGF-I on IGFBP-3 abundance in fibroblast
conditioned media. We show that IGF-I increased IGFBP-3 when assessed by ligand
blotting, but did not increase immunoreactive IGFBP-3, a discrepancy that could be
explained by further data showing an inhibitory effect of IGF-I on the activity of the
fibroblast IGFBP-3 protease. Thus, IGF-I protection of IGFBP-3 from enzymatic
degradation may help explain the post-transcriptional, non-receptor mediated 'stimulation'
of IGFBP-3 by IGF-I in these cells.
We also show for the first time the ability of a number of cytokines to regulate IGFBP
secretion, perhaps indicating a novel pathway of communication between these immune
cell molecules and the IGFs. The inflammatory cytokine interleukin 113(] L-16) inhibited
Hs68 fibroblast IGFBP-3 secretion by down-regulating its gene expression, whilst tumour
necrosis factor oc (TNF(x) had a similar inhibitory effect on IGFBP-3 and IGFBP-4 but
acted via a post-transcriptional mechanism. The exact nature of the TNF(x effect remains
to be determined as no evidence was found to suggest TNF(x increased IGFBP protease
activity, or that TNF(x removed IGFBPs from the conditioned media by increasing the
proportion immobilised on the cell surface. The inhibition of IGFBP secretion by TNF(x
was observed to have marked effects upon the mitogenic activity of IGF-I in these cells,
with a five-fold increase in sensitivity to the growth factor seen in a novel cytochemical
bioassay.
1
Inhibition of fibroblast IGFBP secretion appeared to be restricted to certain cytokines as
IL-6 had no effect, whilst high doses of interferon gamma abolished the TNF(X effect.
Conversely, transforming growth factor 6 (TGFB) directly stimulated fibroblast IGFBP-3
secretion, via an increase in gene expression, and subsequently resulted in the reduction
in the mitogenic activity of IGF-I.
These data indicate that a variety of mechanisms can be employed by a number of factors
to elicit changes in fibroblast IGFBP secretion, and that these changes may have direct
consequencesin determining IGF-I bioactivity. Such is the importance given to the IGFs
in maintaining normal somatic growth, changes in IGFBP secretion may contribute to the
altered cellular growth and metabolism seen associated with cytokines in conditions as
diverse as chronic infection, rheumatoid arthritis, cancer and the wound healing process
The use of decision support systems in making strategic decisions in local authorities : a comparative study of Egypt and the UK
No full textThe application of a modified Technology Acceptance Model (TAM) to determine the
factors affecting the use of Decision Support Systems (DSS) in strategic decisionmaking
in local authorities in both the UK and Egypt was the main core of this
research. Although the use of DSS has become widespread in recent years for
operational control its use in strategic decision-making has only rarely been seen. This
research explores the problems which cause decision-makers not to use DSS
effectively in making strategic decisions. Both the UK and Egypt have long histories
of implementing IT in general and DSS in particular in local government. Although
the UK has longer experience in adopting IT, both countries have failed to achieve the
goals from this technology in a strategic context; however its operational use is quite
good.
The results of this research showed that the percentage of DSS usage in both the UK
and Egypt were 40% and 30% respectively which means more than half of the
investments in this kind of technology have not yet been used properly. This research
has examined the strategic use of DSS and defined the most severe problems that
could face decision makers when they use DSS strategically.
To define the factors that affect DSS usage in making strategic decisions the
researcher used the TAM which was first introduced in 1986 by F. Davis. This model
enjoys a rich base of academic acceptance. Many subsequent studies have proven
reliability of the measures and validity of the constructs and overall model. This study
argues that TAM could be applicable to the context of the strategic use of DSS in local
government in developing countries as it is successfully applied in developed
countries in different kinds of technologies.
This dissertation outlines a framework for the different factors that affect the strategic
use of DSS in both the UK and Egypt. Also this research tries to find answers to the
following questions:
1. What are the problems related to DSS usage in making strategic decisions?
2. What is the relative severity of these problems in both the UK and Egypt?
3. What are the differences between the UK and Egypt relating to the problems that
decision-makers encounter?
The hypotheses of this research were tested using a questionnaire as the main datagathering
instrument in addition to interviews made mainly to validate and support the
results of the quantitative approach. Rigorous validation procedures and statistical
analysis methods were performed on the data, including face and content validity,
alpha Chronbach and Factor analysis. The questionnaire was tested for reliability and
validity and proved to be highly valid and reliable. The results of the analysis
supported all hypothesised relationships.
The results of this research showed that Perceived Usefulness (PU) made a significant
direct effect on DSS usage in the UK group while Perceived Ease of Use (PEU)
showed no significant effect in both countries in all variables apart from the internal
support which was significant in the UK group. Also the results of this research
showed that there was some similarity in both countries regarding the problems of
strategic use of DSS, which were: absence of training for decision-makers to use DSS
and failure to commit the required resources. These results indicate that if DSS is to be
effectively used strategically by decision makers, local government in both developed
and developing countries needs to apply greater funds to training, to making top-level
decision makers comfortable with the use of DSS in hybrid (quantitative/qualitative)
problem contexts and to providing those decision makers with DSS which target
mainly strategic problems
Requirements dilemma
Get PDFThis thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.Knowing ‘what’ to build is an integral part of an Information System Development, and it is generally understood that this, which is known as Requirements, is achievable through a process of understanding, communication and management. It is currently maintained by the Requirements theorists that successful system design clarifies the interrelations between information and its representations. However, this belief can be shown to be based on flawed assumptions, as there are persistent reports of failures, indicating that there is a gap between the theory and the practice, and that this gap needs to be bridged.
A year long in-depth case study of a project group, starting with their strategy announcement and ending with the commissioning system hand-over meeting, followed the group in their ‘doing’ of the Requirements. These mundane meetings were recorded and transcribed, forming a detailed data set of ‘what-is-done’ and ‘how-it-is-done’. The developed research approach adhesively maintained the practical situation, aiming to investigate and make sense of the here-and-now actions of the scoping and defining processes that were at work. The results of the investigation led the researcher to question previous beliefs and assumptions in Requirements, because of ambiguities that were uncovered, also because there was no sufficiently distinct process found that could assuredly be labelled as Requirements. This phenomenon evoked further questioning of “how strange?”, which triggered the testing of the validity of the Requirements theory.
The second stage adapted an analysis framework on decision-making in order to reveal a causal connection between the actions found in the ‘doing’ and in the stocks of knowledge that form the Requirements theory. This phase analysed the operationalization of the theory to examine its commensurate, incommensurate and defective activities. The analysis revealed the existence of other dominant processes that affect the Requirements theory, leaving it underdetermined, with no true causal connections that can be established. This led to the inevitable conclusion that the current Information Systems thinking on Requirements is on the horns of a dilemma without any prospective resolution, because of the elliptical misalignment between the theoretical and the empirical worlds.EPSRC research grant number 00302238 partly funded this wor
