Effect of previous strain hardening on the stainless steel abrasive wear resistance

The main issues regarding emergency breakdown at industrial plants is the premature component wear. In certain applications, the combination of mechanical wear with corrosion is harmful, such as observed in sugar cane processing plants, ore treatment, among others. The use of stainless steel on those applications are the main motivation for the present study. The purpose of this work was to investigate the effect of hardening on abrasive wear on stainless steels. For this, three types of stainless steels were used: ferritic, austenitic, and ferritic-austenitic (duplex). The samples were previous deformed by 15% and 30% of their initial thickness. Tests were performed in two different levels of severities using macroabrasion rubber wheel test and free sphere microabrasion tests. In addition, the hardness profile of the samples was carried out before and after the tests. Those measurements were performed in cross sections of the sample. In the case of worn samples, the hardness profile was measured below the wear scars. The results showed increment of 9% of wear resistance in microabrasion tests performed in ferritic steels subjected due to the cold work. The results presented no influence of previous cold working on macroabrasion wear tests. Analyzes of the wear scars showed that the dynamics predominant in the interface is the particle sliding for microabrasion tests and the particle rolling/sliding for macroabrasion tests. As expected, the different particle dynamics resulted in different wear micromechanisms.CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorCNPq - Conselho Nacional de Desenvolvimento Científico e TecnológicoFAPEMIG - Fundação de Amparo a Pesquisa do Estado de Minas GeraisDissertação (Mestrado)Um dos principais problemas de paradas emergenciais em plantas produtivas é o desgaste prematuro de componentes. Em determinadas aplicações, a combinação de desgaste mecânico com corrosão é danosa como encontrado em usinas de processamento de cana-de-açúcar, tratamento de minério dentre outras. O uso de aços inoxidáveis nessas aplicações se configura na principal motivação do presente estudo. Nesse caso o objetivo deste trabalho é investigar o efeito do encruamento prévio no desgaste abrasivo de aços inoxidáveis. Para isso foram utilizados três tipos de aços inoxidáveis: ferrítico, austenítico e ferrítico-austenítico. Estes foram submetidos à deformação de 15% e 30% em relação a sua espessura inicial. Os testes foram realizados em dois níveis de severidade utilizando os ensaios de macroabrasão tipo roda de borracha e microabrasão tipo esfera livre. Além disso, foi elaborado o perfil de dureza das amostras antes e após os ensaios. Estas medições foram realizadas na seção transversal das amostras. No caso das amostras degastadas, a seção transversal utilizada foi abaixo da marca de desgaste. Os resultados mostraram que há um aumento de 9% na resistência ao desgaste para a microabrasão nos aços ferríticos submetidos ao trabalho a frio. Para os ensaios de macroabrasão, os resultados mostraram que não há influência do trabalho à frio prévio. Análises nas marcas de desgaste mostraram que a dinâmica da partícula predominante na interface de desgaste é o deslizamento de partículas para microabrasão e o deslizamento/rolamento de partículas para o macroabrasão. Como esperado, as diferentes dinâmicas de partículas resultaram em diferentes micromecanismos de desgaste

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

<b>Level of flexibility through sit and reach test from research performed in São Paulo city </b>

The objective of this study was to examine the level of flexibility in men and women of different ages by the sit-and-reach test and to classify them according to the Canadian Standardized Test of Fitness (CSTF). The results were used to elaborate a new table that reflects the population studied. The sample consisted of 16,405 physically active and inactive subjects who were divided according to age: 15 to 19 (n = 954), 20 to 29 (n = 2916), 30 to 39 (n = 2161), 40 to 49 (n = 2333), 50 to 59 (n = 2739), 60 to 69 (n = 3195), and > 70 years (n = 2107). Percentiles were calculated using the original test scores and the 20th, 40th, 60th and 80th percentiles were used as cut-offs for classification as poor, below the average, average, above the average and excellent, respectively. According to the CSTF classification, the age groups from 15 to 39 years were classified as poor, with mean flexibility ranging from 24.805±9.684 to 26.130± 10.111 cm in women and from 21.480±9.905 to 22.848±9.648 cm in men. In the 40- to 69-year age groups, mean flexibility ranged from 22.768±9.627 to 25.396±9.547 in women and from 16.396±10.136 to 19.935±9.192 cm in men and was classified as below the average. Although most of the subjects performed regular exercise, the mean flexibility level observed did not correspond to the average suggested by the CSTF, demonstrating the importance of elaborating national reference tables and of establishing new normative values such as the table proposed in this study

Level of flexibility through sit and reach test from research performed in São Paulo city

The objective of this study was to examine the level of flexibility in men and women of different ages by the sit-and-reach test and to classify them according to the Canadian Standardized Test of Fitness (CSTF). The results were used to elaborate a new table that reflects the population studied. The sample consisted of 16,405 physically active and inactive subjects who were divided according to age: 15 to 19 (n = 954), 20 to 29 (n = 2916), 30 to 39 (n = 2161), 40 to 49 (n = 2333), 50 to 59 (n = 2739), 60 to 69 (n = 3195), and > 70 years (n = 2107). Percentiles were calculated using the original test scores and the 20th, 40th, 60th and 80th percentiles were used as cut-offs for classification as poor, below the average, average, above the average and excellent, respectively. According to the CSTF classification, the age groups from 15 to 39 years were classified as poor, with mean flexibility ranging from 24.805±9.684 to 26.130± 10.111 cm in women and from 21.480±9.905 to 22.848±9.648 cm in men. In the 40- to 69-year age groups, mean flexibility ranged from 22.768±9.627 to 25.396±9.547 in women and from 16.396±10.136 to 19.935±9.192 cm in men and was classified as below the average. Although most of the subjects performed regular exercise, the mean flexibility level observed did not correspond to the average suggested by the CSTF, demonstrating the importance of elaborating national reference tables and of establishing new normative values such as the table proposed in this study.O objetivo do estudo foi identificar o nível de flexibilidade de homens e mulheres de diferentes faixas etárias através do teste de sentar e alcançar seguindo protocolo do Canadian Standardized Test of Fitness (CSTF); classificá-los de acordo com a tabela sugerida pelo mesmo e, a partir dos resultados obtidos elaborar uma nova tabela normativa que reflita a população estudada. Participaram do estudo 16.405 sujeitos (11.114 mulheres e 5.291 homens) praticantes e não praticantes de exercícios físicos regulares, divididos em grupos etários: 15 a 19 (n=954), 20 a 29 (n=2916), 30 a 39 (n=2161), 40 a 49 (n=2333), 50 a 59 (n=2739), 60 a 69 (n=3195), acima de 70 (n=2107). Os percentis foram calculados com escores do teste original e como pontos de corte considerou-se os percentis 20, 40, 60 e 80 para classificação fraco, abaixo da média, média, acima da média, excelente, respectivamente. De acordo com as classificações do CSTF as faixas etárias entre 15 e 39 anos foram classificadas como fraco, com média de flexibilidade variando entre 24,80±9,68cm e 26,13±10,11cm no feminino e entre 21,48±9,90cm e 22,84±9,64cm no masculino. Nas categorias de 40 a 69 a média variou entre 22,76±9,62cm e 25,39±9,54cm no feminino e entre 16,39±10,13cm e 19,93±9,19cm no masculino, ficando abaixo da média. Apesar de a maioria da amostra ser praticante de exercício físico regular, a média do nível de flexibilidade apresentada não correspondeu à média sugerida pela tabela canadense demonstrando a importância de se construir tabelas de referências nacionais e se estabelecer novos valores normativos como a tabela proposta pelo presente trabalho

Incidência de gols na Copa do Mundo de Futebol de 2014

ABSTRACT Incidence of gols in the 2014 world cup of footballIntroduction: Football is a sport characterized by predictable activities could favor the teams that draw up strategies due to the opposing team. The goal is the most important time variable football game, however, there are few studies that analyze the incidence of goals in World Cups. Objective: The objective of the study was to analyze the incidence of temporal goals in the World Cup 2014. Materials and methods: For data collection was used the site Four Four Two®. It analyzed the goals in the 64 matches of the World Cup 2014. Results: The observed results show that there was a significant difference between the last period of the first half to the last sentence of the second half. Conclusion: With this study was difference in the incidence of goals between games of the times, however, the last time of the second half there was a higher incidence of goal in relation to other periods.Introdução: O futebol de campo é um esporte caracterizado por atividades previsíveis e/ou imprevisíveis e desta forma as equipes que elaboram estratégias de jogo levam vantagem em relação à equipe adversária. O gol é a variável temporal mais importante do jogo de futebol, entretanto, não foram encontrados estudos que analisaram a incidência de gols em copas do mundo de futebol. Objetivo: O objetivo do presente estudo foi analisar a incidência de gols dos jogos da copa do mundo de futebol de 2014. Materiais e métodos: Para coleta dos dados foi utilizado o site Four Four Two®. Foi analisada a incidência de gols nos 64 jogos da copa do mundo de futebol de 2014. Resultados: Os resultados observados revelam que houve uma diferença significante entre o último período do primeiro tempo com o último período do segundo tempo. Conclusão: Conclui-se com o presente estudo que houve diferença significativa na incidência de gols entre os tempos dos jogos, no entanto, no último período do segundo tempo existiu uma maior incidência de gols em relação aos demais períodos.

Indicadores técnicos das equipes vencedoras e perdedoras da Liga dos Campeões 2014/2015

Introduction: Football is considered one of the most popular systems in the world, among others, technical indicators of football are devoid of scientific studies. Their study can identify the favorable and unfavorable characteristics of a team and exploit them for their own benefit, which makes it a tool to be investigated by experts in the field in order to contribute to the evolution of sport. Objective: The aim of this study was to compare the technical variables of ball possession (BP), finalization (FI), certain passes (CP), wrong passes (WP) and disarm (DI) of the teams that won and lost, of each match of the knockout phase of the Champions League, season 2014/2015. Materials and Methods: All 29 matches in the knockout round were analyzed, with 7 games being discarded that ended in a draw in the normal time. Results: We observed that the winning teams showed significant difference (p<0.05) in the indicators BP, FI, and CP. The variables WP (p=0.82) and DI (p=0.32) did not present significant differences comparing the winners and losers of the Champions League. Conclusion: It was concluded that the teams that won showed significant differences in the technical indicators showing better results than the teams that lost. However, the technical variables of wrong passes and disarms did not show differences between the winning and loser teams.Introdução: O futebol é considerado um dos esportes mais populares do mundo, entretanto, os indicadores técnicos do futebol são carentes de estudos científicos. O estudo destes pode identificar as características favoráveis e desfavoráveis de uma equipe e explorá-las em benefício próprio, o que a torna uma ferramenta a ser investigada por especialistas da área, a fim de contribuir para evolução do desporto. Objetivo: O objetivo do presente estudo foi comparar os indicadores técnicos de posse de bola (PB), finalização (FI), passes certos (PC), passes errados (PE) e desarmes (DE) das equipes que venceram e das equipes que perderam, em cada uma das partidas da fase eliminatória da Liga dos Campeões (Champions League), temporada 2014/2015. Materiais e métodos: Foram analisadas todas as 29 partidas da fase eliminatória, sendo descartadas 7 partidas que terminaram empatadas no tempo normal. Resultados: Observou-se que as equipes vencedoras apresentaram diferença significante (p<0,05) nos indicadores PB, FI e PC. As variáveis PE e DE não apresentaram diferenças significantes comparando os vencedores e perdedores. Conclusão: Concluiu-se que as equipes que venceram apresentaram diferenças significantes nos indicadores técnicos demonstrando melhores resultados que as equipes que perderam, no entanto, as variáveis técnicas de passes errados e desarmes não demonstraram diferenças entre as equipes vencedoras e perdedoras