280 research outputs found
Towards identifying platinum anchor sites on carbon via a model electrochemical system
No full textThe interaction between Pt and its carbon support was investigated by a model electrochemical system. This entailed aggressively oxidising a two-dimensional carbon substrate, i.e. highly orientated pyrolytic graphite (HOPG) and mirror finish graphite (MFG) quartz crystal, to incorporate oxygen terminated groups into the graphitic matrix. This study focusses on potential cycling to determine the mobility of Pt across these carbon surfaces and the effect of the Pt anchoring to carbon on the electrocatalyst durability. This work incorporates both a conventional three electrode electrochemical setup and the use of the electrochemical quartz crystal nano-balance (EQCN). The objectives of this study were to better understand the Pt mobility across the carbon substrate surface and to gain insight into the solid-liquid interface of Pt dissolution due to potential cycling. Initial results on HOPG as discussed in chapter 2, indicated minimal Pt dissolution of between 13% and 15% of total electrochemical active surface area loss. These results, however, did not provide adequate evidence to conclusively determine the extent of Pt mobility on the carbon surface and the effect of oxygen terminated groups in hindering Pt dissolution. In order to gain a more thorough understanding of the Pt dissolution processes, the use of the EQCN technique was utilised. Firstly, it was shown that the mirror finished graphite quartz crystals used in the EQCN technique, are qualitatively comparable to the electrochemical measurements recorded with the HOPG samples. Secondly, potential cycling under the same conditions as HOPG produced similar electrochemical results. The frequency response curves from the EQCN yielded the most promising results. This study showed, qualitatively, that the surface of Pt is non-monotonic, and that the surface charge changes with increased potential cycling. Pt/MFG-A had consistent frequency responses over the entire potential range during Pt dissolution, thus, with the above understanding of surface charge, it is concluded that acid treated carbon substrates show a stronger affinity for Pt anchoring
Development of a semi–empirical reaction kinetic model for PEM fuel cells
No full textIn the drive to more sustainable energy production, polymer electrolyte fuel cells (PEFC) have been at the pinnacle of global research. One of the major drawbacks of PEFCs is therequirement for expensive noble metal catalysts (platinum and ruthenium). Furthermore 75% of the overpotential losses at the cathode are due to the activation of the oxygen reduction reaction (ORR). To reduce the platinum content requirements and understand the cause of the large overpotential of the ORR, a fundamental understanding of the reaction mechanism and the manner in which it proceeds under different operatingconditions is required. Presently, there still remains a large debate in literature around the mechanism followed by the ORR.This study developed a kinetic model from conventional kinetic isotherms and it is proposed that an associative adsorption mechanism occurs at a low overpotential resulting in the dissociation of the hydroperoxyl species determining the rate of the ORR at the cathode of the PEFC. In order to explain the above phenomena a kinetic model was developed, based on the Eley-Rideal mechanism. Furthermore, experiments were conducted at different oxygen partial pressures and low potentials whereby the associative mechanism is believed to dominate. Under these conditions linear sweep voltammograms were recorded. Regression of the derived kinetic model, by using the values for oxygen partial pressure, applied overpotential and kinetic current allowed for the determination of the kinetic constant of a polycrystalline platinum catalyst for ORR
Pravoslaví, politika a "kirillismus": přehodnocení postsovětské symfonie mezi církví a státem v Rusku za patriarchy Kirilla
No full text. CHARLES UNIVERSITY FACULTY OF SOCIAL SCIENCES Institute of International Studies Thesis Abstract 2022 Paul-Henri Perrain . CHARLES UNIVERSITY FACULTY OF SOCIAL SCIENCES Institute of International Studies Paul-Henri Perrain Orthodoxy, Politics, and Kirillism: Reassessment of Post-Soviet Church-State Symphonia in Patriarch Kirill's Russia Thesis Abstract Prague 2022 Author: Bc. Paul-Henri Perrain Supervisor: Doc. Adrian Brisku, Ph.D. Academic Year: 2021/2022 Abstract While the Russian Orthodox Church (ROC) occupies a preponderant place in Russian cultural identity, its position as an institution has undergone great changes throughout history. Sometimes under the rule of the tsars, sometimes independent, sometimes marginalised, the ROC is now back in the aftermath of the fall of communism. In this new officially secular state, the Church has managed to restore close ties with the main political authorities of the country and benefits from the proximity and entanglement of the spiritual and temporal powers to defend its own interests. The involvement of the Church in the Russian public sphere is all the more evident since the election of Kirill in 2009 as Patriarch. The principle of symphonia which postulates the independence of the two powers and which should guide Church-State relations after 1991 seems...Department of Russian and East European StudiesKatedra ruských a východoevropských studiíFakulta sociálních vědFaculty of Social Science
Orthodoxy, Politics, and Kirillism: Reassessment of Post-Soviet Church-State Symphonia in Patriarch Kirill's Russia
No full text. CHARLES UNIVERSITY FACULTY OF SOCIAL SCIENCES Institute of International Studies Thesis Abstract 2022 Paul-Henri Perrain . CHARLES UNIVERSITY FACULTY OF SOCIAL SCIENCES Institute of International Studies Paul-Henri Perrain Orthodoxy, Politics, and Kirillism: Reassessment of Post-Soviet Church-State Symphonia in Patriarch Kirill's Russia Thesis Abstract Prague 2022 Author: Bc. Paul-Henri Perrain Supervisor: Doc. Adrian Brisku, Ph.D. Academic Year: 2021/2022 Abstract While the Russian Orthodox Church (ROC) occupies a preponderant place in Russian cultural identity, its position as an institution has undergone great changes throughout history. Sometimes under the rule of the tsars, sometimes independent, sometimes marginalised, the ROC is now back in the aftermath of the fall of communism. In this new officially secular state, the Church has managed to restore close ties with the main political authorities of the country and benefits from the proximity and entanglement of the spiritual and temporal powers to defend its own interests. The involvement of the Church in the Russian public sphere is all the more evident since the election of Kirill in 2009 as Patriarch. The principle of symphonia which postulates the independence of the two powers and which should guide Church-State relations after 1991 seems..
Survey report 2003/04 summer season Australian Antarctic Division Author - Adrian Corvino / University of Melbourne
No full textProgress Code: completedStatement:
See the report for further information.
The values provided in spatial coverage are approximate only.Taken from sections of the report:<br/><br/>Introduction<br/><br/>This report describes aspects of the fieldwork completed for the Australian Antarctic Division (AAD) mapping program during the Austral summer 2003-04. The mapping program was undertaken in harmony and collaboration with the Geoscience Australia geodesy program in Antarctica, between 16th November 2003 and 2nd February 2004. Surveyors from both organisations, including Henk Brolsma (Mapping Officer, AAD) and A. Corvino (author), teamed up to successfully complete a wide range of goals. The principal objective of the Geoscience Australia geodesy program was to install three remotely located continuous GPS stations in the southern Prince Charles Mountains (PCM) and Grove Mountains (Corvino, 2004). That project is not discussed further in this report. The main objectives of the AAD mapping program were to survey ground control points (GCPs) for geo-referencing new satellite imagery and to complete terrestrial survey work in the vicinity of Davis station. The following tasks were completed:<br/><br/>- Downloading of the tide gauges at the Larsemann Hills and Davis station;<br/>- Transfer of local sea level at the Davis tide gauge to an absolute height datum using GPS;<br/>- Establishing a new survey mark at Beaver Lake and connecting it to the existing survey marks;<br/>- Conducting GPS surveys of selected ground features for geo-referencing satellite imagery at Beaver Lake, Marine Plain, the Grove Mountains and Wilson Bluff;<br/>- Establishing new survey marks at Marine Plain in the Vestfold Hills;<br/>- Computing the alignment of the UWOSCR instrument in the Space and Atmospheric Sciences (SAS) building at Davis station;<br/>- Surveying lake levels in the Vestfold Hills; and<br/>- Various local surveying tasks at Davis station.<br/><br/>A few aspects of the fieldwork that were completed exclusively by surveyor Brolsma are not included in this report. In particular the report is concerned with the tasks that were undertaken using GPS survey methods, which includes the tide gauge surveys, image control surveys and the fieldwork at Beaver Lake and Marine Plain. Photographs that document the fieldwork and support the text are included throughout. GPS processing reports and photographs showing the locations of the GCPs are provided as Appendices
Government expenditures as a citizens'evaluation of public output : public choice and the benefit principle of taxation
No full textCombining elements from the theories of public choice and benefit taxation, the author develops a framework in which private citizens can evaluate public activities. Why, and under what circumstances, do bureaucrats increase the size of the public sector and the amount of public spending in their own self interest? What does the private sector think public output should be, what is actual public output, and how does the private sector evaluate that output? The author applies the theoretical results of an attempt to answer these questions in four Central European countries (Czechoslovakia, Hungary, Poland, and Slovenia), using actual data for 1989-91 and projections for 1992. Interpreting indirect evidence, he shows that the private sector would prefer less government activity in all countries, from a low of 5 percent less public spending (in Poland) to a high of one-third less (in Slovenia). If those governments were to follow those guidelines, their spending-to-GDP ratios would more closely resemble the 1987-89 average for a selected group of European market economies. The author also introduces a more rigorous, if not necessarily more objective, approach to determining optimal government spending. This approach requires little information, but uses a static model and requires faith in the direction of causality for some key variables. To the extent that one can accept those limitations, the model may be a useful operational tool in public spending evaluation.Public Sector Economics&Finance,National Governance,Economic Theory&Research,Environmental Economics&Policies,Fiscal&Monetary Policy
"Hablo por mi diferencia" The Rebirth of Lemebel From Los incontables to "Manifiesto"
No full text47 pg.All of Lemebel's works have been studied, analyzed, and critiqued, while Los incontables has been either forgotten or unheard of, which is why I attempt a queer reading of these texts. This investigation reaches beyond a need to "rescue" more of Lemebel's works than he has chosen to do by himself; they are analyzed as destabilizing tools of subversion. At the same time, a reworking of Lemebel's stories written and published during Pinochet's dictatorship gives testament to a form of memory hitherto little explored, one that rewrites the official story of the military regime of Chile from the perspective of the sexually deviant and socially marginalized. Los incontables gives voice to the sexually marginalized, those with no History on either side of the battle. I also explore the author as in transformation, analyzing Los incontables and "Manifiesto: Hablo por mi diferencia" as works that mark his convergence from Mardones to Lembel, a political act of resistance against national hegemonic structures of repression.Advisor(s): Perez-Melgosa, Adrian . Committee Member(s): Firbas, Paul.Stony Brook University Libraries. SBU Graduate School in Department of Hispanic Languages and Literature. Charles Taber (Dean of Graduate School)
Civic Virtue in a Christian Mind: Charles Rollin and the Jansenist Influence on the Revival of Classical Virtue in France
No full textThe French Revolution, like much else in the eighteenth century, was undeniably influenced by a revival of classical Greco-Roman themes, particularly in the realm of politics. Unfortunately, classical civic virtue in the French context has generally been viewed as a largely secular affair. In fact, the turn toward classical republican thought was also markedly influenced by the Augustinian theological beliefs of the Jansenists, an austere group of Catholics. One of their number, Charles Rollin, a prominent educator and author, played an important role in revising French education, placing a great deal of emphasis on the instruction of virtue. This thesis will demonstrate the connections between the religious tenets of the Jansenists and the classical republican civic virtue that Rollin prescribes as a remedy not for the individual soul, but for the political and social health of the patrie
BOOK REVIEW: Review of Return to Antarctica: the amazing adventure of Sir Charles Wright on Robert Scott’s journey to the South Pole, by Adrian Raeside
No full textThis book is mainly the result of a visit made to Antarctica in general and the historic huts on Ross Island in particular. The author is the grandson of Sir Charles Wright, who was a physicist and glaciologist during Captain Scott’s last expedition aboard Terra Nova (1910-13). Indeed much is derived from his grandfather’s diary published in 1993. Wright was a member of the party which found Scott’s last camp after the 1912 winter.
(Published: 23 August 2011)
Citation: Polar Research 2011, 30, 7440, DOI: 10.3402/polar.v30i0.744
Impact of the International Coffee Agreement's export quota system on the World's coffee market
No full textEx-post simulations of the global coffee model over the recent period of operation of the International Coffee Agreement's export quota system, (1981-86) show the following. The quota system had a stabilizing effect on world coffee prices in the 1981-85 period. In 1986, when coffee prices increased sharply due to the drought in Brazil and the export quotas were suspended, prices would have been 24 percent higher in the absence of quotas over the 1981-85 period. However, the quotas have reduced export revenues (in real terms), except for such large producers as Brazil and Colombia. These countries gained form the scheme because they face very small or even zero marginal export revenues from increased exports, due to their large market shares. In projections of the coffee market, with and without the export quota system, prices would be substantially lower during the first half of the 1990s if the quota system were suspended in 1990. But prices would recover in the second half of the decade as production and exports declined in lagged response to the very low prices of the first half.Economic Theory&Research,Environmental Economics&Policies,Markets and Market Access,Access to Markets,Crops&Crop Management Systems
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