Cash flow forecast for South African firms

This paper applies models in the extant literature that have been used to forecast operating cash flows to predict the cash flows of South African firms listed on the Johannesburg Stock Exchange. Out-of-sample performance is examined for each model and compared between them. The reported results show that some accrual terms, i.e. depreciation and changes in inventory do not enhance cash flow prediction for the average South African firm in contrast to the reported results of studies in USA and Australia. Inclusion of more explanatory variables does not necessarily improve the models, according to the out-of-sample results. The paper proposes the application of moving average model in panel data, and vector regressive model for multi-period-ahead prediction of cash flows for South Africa firms

Climate Change Mitigation Technologies: Carbon Capture and Storage in the Brazilian scenario

In the present paper, it is intended to analyze how CCS (Carbon Capture, Transport, and Storage) activities are linked to the Sustainable Development Goals and how Brazil can adjust itself in regulatory terms to the activities in question, especially in the ambit of the requirements for its environmental licensing. The Environmental Impact Assessment (EIA) is a necessary support for the Environmental Licensing process of activities that cause significant environmental degradation, as it is suggested that the activities of Carbon Capture, Storage, and Transport associated with the exploration and production of oil and gas. After the assessment, the environmental agency may grant environmental licenses. Based on the analogy to existing norms in our planning, this paper presents possible alternatives to the environmental licensing of CCS activities in Brazil. Thus, from a study case, specifically, considering the potential for the construction of salt caves for carbon storage in the pre-salt area, we concluded that it is possible to draw alternatives rules to achieve offshore storage. Keywords: Sustainable Development Goals, CCS (Carbon Capture, Transport, and Storage), Regulation, Environmental License, Salt Cavern DOI: 10.7176/RHSS/11-20-01 Publication date:October 31st 202

Linfoma multicêntrico com metástase no sistema nervoso central em cão. Relato de caso

O artigo não apresenta resumo

Rendimento de tecidos não componentes da carcaça de cordeiros alimentados com glicerina bruta.

Objetivou-se neste trabalho avaliar os efeitos dos níveis de inclusão de glicerina bruta (GB) na dieta cordeiros em terminação sobre o rendimento dos não componentes da carcaça

Influence of nitrogen content on the structural, mechanical and electrical properties of TiN thin films

This paper reports on the preparation of TiNx thin films by d.c. reactive magnetron sputtering. The coating thickness ranged from 1.7 to 4.2 Am and the nitrogen content varied between 0 and 55 at.%. X-Ray diffraction showed the development of the hexagonal a-Ti phase, with strong [002] orientation for low nitrogen contents, where the N atoms fit into octahedral sites in the Ti lattice as the amount of nitrogen is increased. For nitrogen contents of 20 and 30 at.%, the q-Ti2N phase appears with [200] orientation. With further increasing the nitrogen content, the y-TiN phase becomes dominant. The electrical resistivity of the different compositions reproduces this phase behavior. The hardness of the samples varied from approximately 8 GPa for pure titanium up to 27 GPa for a nitrogen content of 30 at.%, followed by a slight decrease at the highest contents. A similar increase of stresses with nitrogen is observed. Structure and composition with the consequent changes in crystalline phases and the lattice distortion were found to be crucial in the evolution of the mechanical properties

Investigation of Cd1-XMgxTe Alloys for Tandem Solar Cell Applications: Preprint

Theoretical modeling of two-junction tandem solar cells shows that for optimal device performance, the bandgap of the top cell should be in the range of 1.6 to 1.8 eV. Cd1-xMgxTe (CMT) alloys have a lattice constant close to that of CdTe, and the addition of a small amount of Mg changes the bandgap considerably. In this paper, we present our work on developing CMT for solar cell applications. CMT films were prepared by vacuum deposition with co-evaporation of CdTe and Mg on substrates heated to 300-400 C. Films with a composition in the range of x = 0 to 0.66 were fabricated, and optical analysis of the films showed that the bandgap of the samples ranged from 1.5 to 2.3 eV and varied linearly with composition. For the fabrication of devices using these alloy films, we also investigated the effect of post-deposition CdCl2 heat treatment. We have investigated junctions between CdS and CMT alloys in the bandgap range of 1.5 to 1.8 eV for tandem cell applications. We have also worked on the ohmic contacts to the CMT alloy films using Cu/Au bilayers, and the preliminary data shows a significant effect of the contact processing on the device performance

Processing Effects on Junction Interdiffusion in CdS/CdTe Polycrystalline Devices

The performance of CdS/CdTe solar cells is strongly impacted by the process used to grow the CdS layer. CdS films grown by chemical-bath deposition (CBD) exhibit lower sublimation (CSS)

A avaliação econômica do suprimento de gás de folhelho para a ute Uruguaiana / The economic evaluation of the shale gas supply to the Uruguaiana thermoelectric power plant

O presente trabalho tem como objetivo avaliar a viabilidade econômica, do uso de recursos não convencionais nacionais, tais como gás de folhelho advindos da Bacia do Paraná pela usina termelétrica de Uruguaiana localizada no Rio Grande do Sul. Esta usina foi a primeira térmica operada a gás natural no Brasil, iniciando suas atividades em 2000, mas está paralisada desde abril de 2009. Este trabalho expõe o potencial real de hidrocarbonetos da Bacia do Paraná. Os resultados indicam que o valor presente da demanda de gás natural (em função da utilização da UTE) pode chegar a um valor de USD 16,21 MMBTU para garantir um retorno hipotético de 5% do investimento. A partir dos resultados obtidos, chega-se à conclusão de que a alternativa não convencional para o projeto não é economicamente mais viável na data do estudo do que a importação de GNL, porém é preciso levar em consideração que todos os projetos e investimentos feitos na área do petróleo e gás estão sujeitos a riscos, e à mercê das flutuabilidades desta commodity, que foi evidenciada pela pandemia do COVID19

Desafios para a implantação de projetos de gás não convencional: estudo comparativo brasil e europa / Challenges for the implementation of non-conventional gas projects: comparative study brazil and europe

O gás não convencional desempenhou um papel relevante no setor de energia e na economia dos EUA, razão pela qual muitos países consideraram a exploração e a produção não convencional como uma oportunidade para o desenvolvimento do seu setor energético e da sua economia. No entanto, o Brasil e os países da União Europeia têm uma posição mais cautelosa e relutante com relação aos potenciais impactos gerados pela exploração e produção desta fonte de energia. O objetivo desse artigo é descrever e analisar os desafios existentes para as atividades de gás não convencional no Brasil, especificamente, em alguns estados, assim como em alguns países europeus. A metodologia é qualitativa analítica, a partir de uma revisão da literatura bibliográfica. Os resultados apontam que as barreiras ao avanço do gás não convencional no Brasil são sobretudo leis estaduais que proíbem a atividade exploratória desta fonte energética. Relativamente à União Europeia, apresentam-se desafios particulares na Espanha, Reino Unido, França e Polônia que serão analisados ao longo deste trabalho