987 resultados para CO-ADSORPTION


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Individual and/or co-offenders fraudulent activities can have a devastating effect on a company’s reputation and credibility. Enron, Xerox, WorldCom, HIH Insurance and One.Tel are examples where stakeholders incurred substantial financial losses as a result of fraud and led to a loss of confidence in corporate dealings by the public in general. There are numerous theoretical approaches that attempt to explain how and why fraudulent acts occur, drawing on the fields of sociology, organisational, management and economic literature, but there is limited empirical evidence published in accounting literature. This qualitative inductive study analyses perceptions and experiences of forensic accountants to gain insights into individual fraud and co-offending in order to determine whether the conceptual framework developed from literature accurately depicts the causes of fraud committed by individuals and groups in the twenty-first century. Findings from the study both support and extend the conceptual framework, demonstrating that strain and anomie can result in fraud, that deviant sub-groups recruit and coerce members by providing relief from strain, and that inadequate corporate governance mechanisms both contribute to fraud occurring, and provide the opportunity for fraudulent activities to be executed and often remain undetected. Additional factors emerging from this study (the ‘technoconomy’, addiction and IT measures) were also identified as contributors to fraud, particularly relevant to the twenty-first century, and consequently, a refined conceptual framework is presented in the discussion and conclusion to the paper.

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The tie lines delineating ion-exchange equilibria between MCr2O4-MAl2O4 spinel solid solution, where M is either Mn or Co, and Cr2O3-Al2O3 solid solution with the corundum structure were determined at 1373 K by electron microprobe and E0AX point count analysis of the oxide phases equilibrated with metallic Co and Au-5% Mn. The component activities in the spinel solid solutions are derived from the tie lines and the thernodynamic data for Cr2O3-Al2O3 soiid solutions available hi the literature. The Gibbs free energies of mixing calculated from the experimental data are discussed in relation to the values derived from the cation distribution a.odel based on the site preference energies and assuming random mixing on both tetrahedral and octahedral sites. Positive deviations from ideality observed in this study suggest a miscibility gap for both series of spinel solid solutions at low temperatures in the absence of oxidation.

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Because of growing environmental concerns and increasingly stringent regulations governing auto emissions, new more efficient exhaust catalysts are needed to reduce the amount of pollutants released from internal combustion engines. To accomplish this goal, the major pollutants in exhaust-CO, NOx, and unburned hydrocarbons-need to be fully converted to CO2, N-2, and H2O. Most exhaust catalysts contain nanocrystalline noble metals (Pt, Pd, Rh) dispersed on oxide supports such as Al2O3 or SiO2 promoted by CeO2. However, in conventional catalysts, only the surface atoms of the noble metal particles serve as adsorption sites, and even in 4-6 nm metal particles, only 1/4 to 1/5 of the total noble metal atoms are utilized for catalytic conversion. The complete dispersion of noble metals can be achieved only as ions within an oxide support. In this Account, we describe a novel solution to this dispersion problem: a new solution combustion method for synthesizing dispersed noble metal ionic catalysts. We have synthesized nanocrystalline, single-phase Ce1-xMxO2-delta and Ce1-x-yTiyMxO2-delta (M = Pt, Pd, Rh; x = 0,01-0.02, delta approximate to x, y = 0.15-0.25) oxides in fluorite structure, In these oxide catalysts, pt(2+), Pd2+, or Rh3+ ions are substituted only to the extent of 1-2% of Ce4+ ion. Lower-valent noble metal ion substitution in CeO2 creates oxygen vacancies. Reducing molecules (CO, H-2, NH3) are adsorbed onto electron-deficient noble metal ions, while oxidizing (02, NO) molecules are absorbed onto electron-rich oxide ion vacancy sites. The rates of CO and hydrocarbon oxidation and NOx reduction (with >80% N-2 selectivity) are 15-30 times higher in the presence of these ionic catalysts than when the same amount of noble metal loaded on an oxide support is used. Catalysts with palladium ion dispersed in CeO2 or Ce1-xTixO2 were far superior to Pt or Rh ionic catalysts. Therefore, we have demonstrated that the more expensive Pt and Rh metals are not necessary in exhaust catalysts. We have also grown these nanocrystalline ionic catalysts on ceramic cordierite and have reproduced the results we observed in powder material on the honeycomb catalytic converter. Oxygen in a CeO2 lattice is activated by the substitution of Ti ion, as well as noble metal ions. Because this substitution creates longer Ti-O and M-O bonds relative to the average Ce-O bond within the lattice, the materials facilitate high oxygen storage and release. The interaction among M-0/Mn+, Ce4+/Ce3+, and Ti4+/Ti3+ redox couples leads to the promoting action of CeO2, activation of lattice oxygen and high oxygen storage capacity, metal support interaction, and high rates of catalytic activity in exhaust catalysis.

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Non-governmental organisations (NGOs) have gained an important role in development co-operation during the last two decades. The development funding channelled through NGOs has increased and the number of NGOs engaged in development activities, both North and South, has been growing. Supporting NGOs has been seen as one way to strengthen civil society in the South and to provide potential for enhancing more effective development than the state, and to exercise participatory development and partnership in their North-South relationships. This study focuses on learning in the co-operation practices of small Finnish NGOs in Morogoro, Tanzania. Drawing on the cultural-historical activity theory and the theory of expansive learning, in this study I understand learning as a qualitative change in the actual co-operation practices. The qualitative change, for its part, emerges out of attempts to deal with the contradictions in the present activity. I use the concept of developmental contradiction in exploring the co-operation of the small Finnish NGOs with their Tanzanian counterparts. Developmental contradiction connects learning to actual practice and its historical development. By history, in this study I refer to multiple developmental trajectories, such as trajectories of individual participants, organisations, co-operation practices and the institutional system in which the NGO-development co-operation is embedded. In the empirical chapters I explore the co-operation both in the development co-operation projects and in micro-level interaction between partners taking place within the projects. I analyse the perceptions of the Finnish participants about the different developmental trajectories, the tensions, inclusions and exclusions in the evolving object of co-operation in one project, the construction of power relations in project meetings in three projects, and the collision of explicated partnership with the emerging practice of trusteeship in one project. On the basis of the empirical analyses I elaborate four developmental contradictions and learning challenges for the co-operation. The developmental contradictions include: 1) implementing a ready-made Finnish project idea vs. taking the current activities of Tanzanian NGO as a starting point; 2) gaining experiences and cultural interaction vs. access to outside funding; 3) promoting the official tools of development co-operation in training vs. use of tools and procedures taken from the prior activities of both partners in actual practice; and 4) asymmetric relations between the partners vs. rhetoric of equal partnership. Consequently, on the basis of developmental contradictions four learning challenges are suggested: a shift from legitimation of Finnish ideas to negotiation, transcending the separate objects and finding a partly joint object, developing locally shared tools for the co-operation, and identification and reflection of the power relations in the practice of co-operation. Keywords: activity theory; expansive learning; NGO development co-operation; partnership; power

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Rabbit Haemorrhagic Disease Virus (RHDV) was introduced to Australia in 1995 for the control of wild rabbits. Initial outbreaks greatly reduced rabbit numbers and the virus has continued to control rabbits to varying degrees in different parts of Australia. However, recent field evidence suggests that the virus may be becoming less effective in those areas that have previously experienced repeated epizootics causing high mortality. There are also reports of rabbits returning to pre-1995 density levels, Virus and host can be expected to co-evolve. The host will develop resistance to the virus with the virus subsequently changing to overcome that resistance. It has been 12 years since the release of RHDV and it is an opportune time to examine where the dynamic currently stands between RHDV and rabbits. Laboratory challenge tests have indicated that resistance to RHDV has developed to different degrees in populations throughout Australia. In one population a low dose (1:25 dilution) of Czech strain RHDV failed to infect a single susceptible rabbit, yet infected a low to high (up to 73%) percentage across other populations tested. Different selection pressures are present in these populations and will be driving the level of resistance being seen. The mechanisms and genetics behind the development of resistance are also important as the on-going use of RHDV as a control tool in the management of rabbits relies on our understanding of factors influencing the efficacy of the virus. Understanding how resistance has developed may provide clues on how best to use the virus to circumvent these mechanisms. Similarly, it will help in managing populations that have yet to develop high levels of resistance.

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Commercial and recreational harvesting of pigs is often encouraged by pest managers because it is essentially a ‘free’ reduction in pest density. However, the reduction in numbers may provide minimal damage mitigation and may be inappropriately allocated in space and time. Additionally, more effective control (e.g. baiting) may not occur because of the incorrect perception that harvesting is effective or because pigs are valued for recreational use.

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The oxides of cobalt have recently been shown to be highly effective electrocatalysts for the oxygen evolution reaction (OER) under alkaline conditions. In general species such as Co3O4 and CoOOH have been investigated that often require an elevated temperature step during their synthesis to create crystalline materials. In this work we investigate the rapid and direct electrochemical formation of amorphous nanostructured Co(OH)2 on gold electrodes under room temperture conditions which is a highly active precursor for the OER. During the OER some conversion to crystalline Co3O4 occurs at the surface, but the bulk of the material remains amorphous. It is found that the underlying gold electrode is crucial to the materials enhanced performance and provides higher current density than can be achieved using carbon, palladium or copper support electrodes. This catalyst exhibits excellent activity with a current density of 10 mA cm-2 at an overpotential of 360 mV with a high turnover frequency of 2.1 s-1 in 1 M NaOH. A Tafel slope of 56 mV dec-1 at low overpotentials and a slope of 122 mV dec-1 at high overpotentials is consistent with the dual barrier model for the electrocatalytic evolution of oxygen. Significantly, the catalyst maintains excellent activity for up to 24 hr of continuous operation and this approach offers a facile way to create a highly effective and stable material.

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Background and Aims: Success of invasive plant species is thought to be linked with their higher leaf carbon fixation strategy, enabling them to capture and utilize resources better than native species, and thus pre-empt and maintain space. However, these traits are not well-defined for invasive woody vines. Methods: In a glass house setting, experiments were conducted to examine how leaf carbon gain strategies differ between non-indigenous invasive and native woody vines of south-eastern Australia, by investigating their biomass gain, leaf structural, nutrient and physiological traits under changing light and moisture regimes. Key Results: Leaf construction cost (CC), calorific value and carbon : nitrogen (C : N) ratio were lower in the invasive group, while ash content, N, maximum photosynthesis, light-use efficiency, photosynthetic energyuse efficiency (PEUE) and specific leaf area (SLA) were higher in this group relative to the native group. Trait plasticity, relative growth rate (RGR), photosynthetic nitrogen-use efficiency and water-use efficiency did not differ significantly between the groups. However, across light resource, regression analyses indicated that at a common (same) leaf CC and PEUE, a higher biomass RGR resulted for the invasive group; also at a common SLA, a lower CC but higher N resulted for the invasive group. Overall, trait co-ordination (using pair-wise correlation analyses) was better in the invasive group. Ordination using 16 leaf traits indicated that the major axis of invasive-native dichotomy is primarily driven by SLA and CC (including its components and/or derivative of PEUE) and was significantly linked with RGR. Conclusions: These results demonstrated that while not all measures of leaf resource traits may differ between the two groups, the higher level of trait correlation and higher revenue returned (RGR) per unit of major resource need (CC) and use (PEUE) in the invasive group is in line with their rapid spread where introduced.

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The Cape York Peninsula Land Use Strategy (CYPLUS) is a joint Queensland/Commonwealth initiative to provide a framework for making decisions about how to use and manage the natural resources of Cape York Peninsula in ways that will be ecologically sustainable. As part of the Natural Resources Analysis Program (NRAP) of CYPLUS, the Fisheries Division of the Queensland Department of Primary Industries has mapped the marine vegetation (mangroves and seagrasses) for Cape York Peninsula. The project ran from July 1992 to June 1994. Field work was undertaken in November 1992, May 1993, and April 1994. Final report on project: NRO6 – Marine Plan (Seagrass/Mangrove) Distribution. Dataset URL Link: Queensland Coastal Wetlands Resources Mapping data. [Dataset]

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Addressed to Therese Gottschalk nee Molling, postmarked 25 April 1905 and mailed from Hannover to Hildesheim, most likely while Therese was visiting her Meyerhof grandparents

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Addressed to Therese Gottschalk nee Molling, postmarked 25 April 1905 and mailed from Hannover to Hildesheim, most likely while Therese was visiting her Meyerhof grandparents

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Background: The territorial fishing zones of Australia and Indonesia are contiguous to the north of Australia in the Timor and Arafura Seas and in the Indian Ocean to the north of Christmas Island. The area surrounding the shared boundary consists of a variety of bio-diverse marine habitats including shallow continental shelf waters, oceanic trenches and numerous offshore islands. Both countries exploit a variety of fisheries species, including whaler (Carcharhinus spp.) and hammerhead sharks (Sphyrna spp.). Despite their differences in social and financial arrangements, the two countries are motivated to develop complementary co-management practices to achieve resource sustainability. An essential starting point is knowledge of the degree of population subdivision, and hence fisheries stock status, in exploited species. Results: Populations of four commercially harvested shark species (Carcharhinus obscurus, Carcharhinus sorrah, Prionace glauca, Sphyrna lewini) were sampled from northern Australia and central Indonesia. Neutral genetic markers (mitochondrial DNA control region sequence and allelic variation at co-dominant microsatellite loci) revealed genetic subdivision between Australian and Indonesian populations of C. sorrah. Further research is needed to address the possibility of genetic subdivision among C. obscurus populations. There was no evidence of genetic subdivision for P. glauca and S. lewini populations, but the sampling represented a relatively small part of their distributional range. For these species, more detailed analyses of population genetic structure is recommended in the future. Conclusion: Cooperative management between Australia and Indonesia is the best option at present for P. glauca and S. lewini, while C. sorrah and C. obscurus should be managed independently. On-going research on these and other exploited shark and ray species is strongly recommended. Biological and ecological similarity between species may not be a predictor of population genetic structure, so species-specific studies are recommended to provide new data to assist with sustainable fisheries management.