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Study on the Reaction Mechanisms of Gas-liquid Phase of Nitrogen-containing Pollutants over Nanoscale Copper CatalystHung, Chang-Mao 25 June 2003 (has links)
Ammonia is one of valuable chemicals, which are commonly used, in various industrial factors. It is also a typical pollutant, and has a long-term impact on human health for its toxicity characteristics. This study investigated the reaction mechanism of gas-liquid phase in oxidation of ammonia in WAO and SCO processes over copper catalysts. As for lack of the research on activated center of copper catalyst for a long time, it was still not exactly unknown what center was going on affecting activity. Therefore, we conducted the physical and chemical properties on surface of catalyst to realize conversion/activity in oxidation of ammonia over nanoscale copper catalyst.
Achievements in oxidation of liquid phase ammonia in WAO process over nanoscale Cu-La-Ce catalysts are as follows: (1) The raising on conversion of ammonia is significantly by adding the molar ratio 7:2:1 of Cu-La-Ce catalyst. (2) The higher temperature the higher conversion, and the increasing space velocity of influent the lower conversion. (3) The reaction rate in WAO process over 7:2:1 catalyst increases with initial pH increasing of solution, 95% conversion of ammonia can be achieved under alkalinity condition. (4) Oxygen supply can promote the decomposition of ammonia at high temperature, above 95% conversion of ammonia can be achieved when total pressure raises at 4.0 MPa. (5) The characteristic peaks of CuO, La2O3 and CeO2 showed from XRD tests indicate the coordination by three peaks probably causes the excellent activity in Cu-La-Ce catalysts; UV-Vis and FTIR analysis results show CuO species dominates the reaction mechanism of liquid phase of WAO process over Cu-La-Ce catalyst which can be used to adsorb the oxygen atom in proceeding the oxidation of ammonia. (6) AEM and TEM analysis results show the outlook of catalyst sites are almost nearly circular and its particle sizes are concentrated in range of nanoscale level; and by EDS and Mapping tests proof elements of Cu, La and Ce are indeed the major components in this catalyst.
Achievements in oxidation of liquid phase ammonia in WAO process over nanoscale Cu-ACF catalysts are as follows: (1) The dose of copper on activated carbon fiber support (denoted by ACF) is important in treatment efficiency of pollutants removal; adding at least 5% of copper dosage which can maintain Cu to be a state of +2, it has the catalytic capacity to convert the ammonia in solution. (2) The optimal conversion obtained in 99% under 463 K and 400 mg/l, shows Cu-ACF is also an alterative catalyst. (3) The higher temperature the higher conversion, and the lower nitrogen is. (4) The higher oxygen pressure the higher conversion. (5) From analysis results of BET, FTIR and EA show ACF support has high BET surface area and oxygen-containing function groups, it causes an increasing activity of metal in reaction for the higher activated sites and metal dispersed uniformly on ACF; XRD tests indicate the coordination by CuO and ACF probably causes the excellent activity over Cu-ACF catalysts; UV-Vis and FTIR analysis results show species CuO and ACF both dominate the reaction mechanism of liquid phase of WAO process over Cu-ACF catalyst. (6) AEM and TEM analysis results show the outlook of catalyst sites are almost Nearly long narrowed tube and its diameters are concentrated in range of nanoscale level; and by EDS and XRF (Mapping) tests proof elements of Cu and P are indeed the major components in this catalyst.
Achievements in oxidation of gas phase ammonia in SCO process over nanoscale Cu-Ce catalysts are as follows: (1) The great conversion over Cu-Ce catalyst (molar ratio 6:4) obtained under 463 K and 400 mg/l. (2) The higher initial concentration of ammonia the lower conversion is probably due to the intermediates out of completely decomposed in catalytic reaction. (3) From analysis results of BET and EA show this catalyst have high BET surface area and empty hole of oxygen-containing on surface, it causes an increasing activity of metal in reaction for the higher activated sites; XRD tests indicate the coordination by CuO and CeO2 probably causes good activity over Cu-Ce catalysts; UV-Vis and FTIR analysis results show species CuO and CeO2 both dominate the reaction mechanism of gas phase of ammonia in SCO process over Cu-CeO2 catalyst. (4) AEM and TEM analysis results show the outlook of catalyst sites are almost nearly circular and its particle sizes are concentrated in range of nanoscale level; and by EDS and Mapping tests proof elements of Cu and Ce are indeed the major components in this catalyst.
Achievements in oxidation of gas phase ammonia in SCO process over nanoscale Pt-Pd-Rh catalyst coated on ceramics are as follows: (1) The 99% conversion over this catalyst can be obtained at 623 K; the higher initial concentration of ammonia ranging from 500 to 1000 mg/l the lower conversion is found. (2) The large amount of N2 and minor amount of NO and NO2 are found in the products after this reaction. (3) XRD tests indicate the coordination by Pt, PdO, Rh and CeO2 probably causes the excellent activity over this catalyst; UV-Vis and FTIR analysis results show species PdO and CeO2 both dominate the reaction mechanism of gas phase of ammonia in SCO process over Pt-Pd-Rh catalyst. (4) AEM and TEM analysis results show the higher initial concentration the higher aged the ceramic support, and the wider sintering of Al2O3 coating layer is. (5) By EDS, XRF and Mapping tests proof elements of Pt, Pd and Rh are indeed the major components dispersed on this ceramic catalyst.
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Study on the treatment of ammonia-containing solutions over Cu/ACF catalystChen, Kuan-Hung 23 June 2003 (has links)
Abstract
Ammonia is one of valuable chemicals which are commonly used in various industrial factors. It is also a typical pollutant, and has a long-term impact on human health for toxicity characteristics. This study was to investigate the performance, product selectivity and kinetics in oxidation of ammonia solution in WAO process over Cu/ACF catalyst. The operation parameters in continuous WAO process were performed as follows: initial concentration of ammonia in ranging from 200 ppm to 1000 ppm, pH at 12, velocity of influent at below 3.0 ml/min, temperature ranging from 443K to 463K and pressure at 3.0 MPa.
In the experiments of catalyst selection, we decided to use 5% Cu/ACF catalyst for its high conversion and selectivity in oxidation of ammonia. A conversion of 95.42% in oxidation of ammonia was achieved under 463K and the product selectivity of N2 was raised from 53% to 85%. We found that Cu/ACF and ACF catalysts both had the good conversion and selectivity in oxidation of ammonia in WAO process.
In the long-term test of catalyst stability, Cu/ACF had a bad stability after 48 hours reaction in WAO process. The tests such as XRD, SEM and EA were also determined. The kinetics of WAO over Cu/ACF catalyst in oxidation of ammonia using Power-Rate Law was presented. The apparent reaction order and activated energy were obtained.
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Study on the treatment of ammonia solutions over Cu/La/Ce catalyst supported on ceramic powderChen, Chun-Yang 23 June 2003 (has links)
Abstract
The purpose of this study was to investigate the removal performance in oxidation of ammonia solution, synthesized concentration in range of 200 mg/l -1000 mg/l, in continuous WAO process over Cu/La/Ce catalyst. The operation parameters in WAO process were performed as follows: reaction temperature, influent velocity, initial concentration of ammonia and oxygen pressure.
During the first stage WAO test, ammonia conversion only reached to 40.1% under the conditions performed as follows: initial concentration of ammonia in 400 mg/l, 12 of pH, 453 K of temperature, 3.0 MPa of total pressure and 3.0 ml/min of influent velocity.
In the second stage experiments conducted by 453 K, pH 12, 3.0MPa and 400 mg/l, the ammonia conversion was above 86.2% over catalyst in WAO process. In addition, the conversion of ammonia were found to be 89%, 82.6%, 81.6% and 79.3% when the initial concentration were regulated in 200, 400, 800 and 1000 mg/l respectively; 91.4% conversion of ammonia could be obtained when temperature was raised at 473 K.
The tests such as XRD, SEM, EDS, ICP-MS and EA were also determined. The kinetics of WAO over Cu/La/Ce catalyst in oxidation of ammonia solutions using Power-Rate Law was presented to calculate the apparent reaction order and activated energy.
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At Second Glance: Retroactive Continuity in Junot Díaz’s <em>The Brief Wondrous Life of Oscar Wao</em>Clawson, Stephen Clancy 09 March 2012 (has links) (PDF)
This work explores Junot Díaz’s incorporation of nerd culture into his novel, The Brief Wondrous Life of Oscar Wao, and that move's larger impact on the genre of trauma narratives. By using allusions to nerd texts such as The Lord of the Rings to structure his depiction of the brutal reign of Dominican dictator Rafael Leónidas Trujillo Molina, Díaz effectively rewrites Dominican history, creating a retroactive continuity of fantasy. Retroactive continuity, or retcon, is a little-discussed interpretive strategy of the nerd community with striking parallels to Lacanian notions of fantasy. A reading of Díaz's retcon ultimately casts doubt on the silent victim's traditional role as the foundation of trauma narratives, suggesting instead that the ideological root of these stories is actually the hypothetical denier of trauma.
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Taking Issue with History: Empathy and the Ethical Imperatives of Creative InterventionsVera, Monica A 01 January 2012 (has links)
The purpose of this thesis was to contribute to a dialogue that considers the relationship between history, literature, and empathy as a literary affect. Specifically, I explored sites of literature’s transformative potential as it relates to cultural studies and the ethics of deconstruction. Via a deconstructive, post-colonial reading of Toni Morrison’s Beloved and Junot Díaz’s The Brief Wondrous Life of Oscar Wao, I considered how subjects in our current socio-political moment can feel history.
Emerging from a post-structurally mediated engagement with history, signification, and feeling, I argued that empathy, as it is contentiously presented in the context of deconstruction, is not necessarily a reductive or essentialist approach towards relating or “being-with” an-other. Instead, I proposed that the act of reading historiographical novels that take constructions of the Atlantic Slave Trade to task might generate an affective empathy, which could in turn engender a more empathetic relationality and way of being-in-the-world.
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Machismo, Carnival, and the Decolonial Imagination in the Writings of Junot D<Ã>azPrice, Joshua Evans 01 March 2018 (has links)
This work explores Junot Daz as an author of decolonial imagination, and more specifically, how the carnivalesque nature of Dominican machismo as influenced by Trujillos el tguere masculinity creates liminal space for self-determination in opposition to colonial imagination. In exploring Dazs primary masculine characters, Oscar de Leon and Yunior de Las Casas, I trace the initial decolonial turn engendered by tigueraje performance, namely its projective creation of self outside of colonial domination. El tguere machismo as empowering for Dominican males, however, is problematized by its reciprocal domination of both women and men who fail to meet the tigueraje ideal. It becomes an attempted cure that is ultimately symptomatic of the extent to which the effects of insidious ideologies and political policies, in this case, imperialism, perpetuate themselves across time, space, and perhaps most significantly, cultures. Ultimately, identifying Junot Daz as decolonial author is a misrepresentation; though Daz writes to break free of coloniality, his failure to largely acknowledge in his writing the cost and damage done to Dominican women reveals a narrow focus antithetical to the larger goals of decoloniality.
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The Ghosts of Guilt and BetrayalVoller, Leslie Abigail 11 December 2009 (has links)
This creative thesis is comprised of stories that present characters who deal with guilt and betrayal and explores various points of view. My work is informed by Junot Diaz’s The Brief Wondrous Life of Oscar Wao, which contains these themes and investigates narration. “Surviving Fog” centers around survivor’s guilt, while “Coming Full Circle, No Detour in Sight” demonstrates how a person can exert expectations on herself due to a religious background and personal values. Perhaps my most provocative story, “Beyond the Apple Orchard” delves into the emotional and physical betrayal of a father and the daughter’s struggles to overcome it. “Photographic Memories” embraces the surreal with a woman who can “read” photographs, whose story blends past transgressions that bleed into current ones, while “Send in the Clowns, Send in the Mob” explores herd mentality that stems from fear. Ultimately, each story contains kernels of truth that readers can grasp.
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Transnational Compositionality and Hemon, Shteyngart, Díaz; A No Man's Land, Etc.Miner, Joshua D. 08 1900 (has links)
Contemporary transnational literature presents a unique interpretive problem, due to new methods of language and culture negotiation in the information age. The resulting condition, transnational compositionality, is evidenced by specific linguistic artifacts; to illustrate this I use three American novels as a case study: Nowhere Man by Aleksandar Hemon, Absurdistan by Gary Shteyngart, and The Brief Wondrous Life of Oscar Wao by Junot Díaz. By extension, many conventional literary elements are changed in the transnational since modernity: satire is no longer a lampooning of cultures but a questioning of the methods by which humans blend cultures together; similarly, complex symbolic constructions may no longer be taken at face value, for they now communicate more about cultural identity processes than static ideologies. If scholars are to achieve adequate interpretations of these elements, we must consider the global framework that has so intimately shaped them in the twenty-first century.
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The Rebellious Mirror,Before and after 1984:Community-based theatre in AotearoaMaunder, Paul Allan January 2010 (has links)
In this thesis I outline the contribution Community-based theatre has made to New Zealand theatre. This involves a defining of theatre production as a material practice. Community-based theatre was a tendency from the 1930s, a promise of the left theatre movement and, I argue, was being searched for as a form of practice by the avant-garde, experimental practitioners of the 1970s. At the same time, early Māori theatre began as a Community-based practice before moving into the mainstream.
With the arrival of neo-liberalism to Aotearoa in 1984, community groups and Community-based theatre could become official providers within the political system. This led to a flowering of practices, which I describe, together with the tensions that arise from being a part of that system. However, neo-liberalism introduced managerial practices into state contracting and patronage policy, which effectively denied this flowering the sustenance deserved. At the same time, these policies commodified mainstream theatre production.
In conclusion, I argue that in the current situation of global crisis, Community-based theatre practice has a continuing role to play in giving voice to the multitude and by being a practice of the Common.
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