ABSTRACT This study provides evidence of possible sociodemographic characteristics that would influence the intention of Brazilian immigrants to engage in ventures in Canada. Data were collected through surveys released on Brazilian Facebook groups. A total of 675 Brazilian respondents living in Canada were triangulated with data from seven semi-structured interviews conducted in Canada and with two consulate officials. Survey data analysis was performed with logit equations to check relationships between entrepreneurial intention (EI) and variables - namely, gender, age upon arrival, level of education, length of stay in the country, student/work/tourist visa status upon arrival, and citizenship application status/permanent migration. The key results point to factors with a positive influence on the intention to venture: gender (being female) and all visa status and other variables were either non-significant or had a negative influence. Of the entrepreneurs, age upon arrival was a significant predictor. Variables such as level of education, time in the country, and tourist visa had a negative influence. This paper contributes theoretically by evidencing recent immigration patterns and variables related to entrepreneurial venturing in the Brazilian immigrant community in Canada, which may support mechanisms for attracting and fostering future entrepreneurs. Further comparative studies between other Brazilian and ethnic communities are proposed, including other variables.

ABSTRACT The objective of this study was to evaluate the thermal decomposition profile of 10 wood species from the semi-arid region of Brazil using thermogravimetric analysis (TGA) to investigate their potential as biomass energy sources. First, flash carbonization was carried out in a muffle furnace, in which wood samples were heated to a maximum temperature of 500°C, and the product yields were determined. The chemical analysis of the wood of each species for the determination of extractive, lignin and ash contents was performed. TGA was performed using sawdust samples heated at 10°C.min−1 up to 625°C under a nitrogen atmosphere at a flow rate of 50 mL.min−1. The thermal decomposition profile was used to evaluate which wood species was more thermally stable. Mimosa tenuiflora and Poincianella pyramidalis woods were the most suitable as biomass energy sources for charcoal production because of their thermal stability and satisfactory carbonization yields. The thermal stability of the 10 wood samples was confirmed by the analysis of the carbonization yields.

RESUMO As operações de processamento secundário de madeira geram grande quantidade de particulados suspensos no ar. A inalação desse material pode estimular o aparecimento de doenças respiratórias nos trabalhadores expostos nestes ambientes de trabalho. No entanto, no Brasil ainda não há um limite de tolerância definido para partículas de madeira suspensas, necessitando de estudos para embasamento técnico e definição desse limite. Objetivou-se mensurar a concentração e dimensão das partículas de madeira de Eucalyptus spp. suspensas no ar em marcenarias. A análise da concentração das partículas suspensas foi desenvolvida pela utilização de bomba gravimétrica e coletores com filtros. Para dimensionar as partículas suspensas no ar usou-se lâminas, microscópio e fotografias. Os dados foram coletados na lixadeira, serra circular e serra fita, em cinco marcenarias semelhantes, no estado do Espírito Santo. Os particulados mais danosos à saúde humana foram provenientes da lixadeira, que pela pequena dimensão facilitam a deposição nas partes mais prejudiciais ao trato respiratório humano. Constatou-se que as concentrações de partículas suspensas encontradas estão acima dos limites recomendados pelas normas internacionais. Diante do risco de danos severos a saúde, há a necessidade urgente e imprescindível de implementação de medidas para redução dos níveis de exposição (EPC e EPI), bem como a implementação de normatização específica com limites de exposição máximo definidos para o setor no Brasil.

ABSTRACT Wood secondary processing operations generate large amounts of airborne particulates. Inhalation of this material can lead to the development of work-related respiratory diseases. The Brazilian legislation does not define threshold limit values for airborne wood particles, and local studies are required to provide a technical basis for establishing these limits by regulation. This study aimed to determine the concentration and size of airborne wood particles of Eucalyptus spp. in woodworking shops. Analysis of the concentration of airborne particles was carried out using a gravimetric sampling pump and collector filters. The size of airborne particles was determined using microscope slides and an optical microscope coupled to an image capture system. Air samples were collected near different machines (belt sander, table saw, and band saw) at five woodworking shops located in the state of Espírito Santo, Brazil. Of the three machines, the belt sander produced the most harmful type of particulate matter: the small size of these particles allows their deposition deep into the respiratory tract. Particulate matter was above the threshold limit value established by international standards. To prevent the risk of severe health effects, there is an urgent and imperative need to reduce worker exposure levels (by the use of collective and personal protective equipment) as well as for the implementation of specific regulations that define particulate exposure limits for the wood sector in Brazil.

WC/Co is widely used as cutting tools, because has a unique combination of high strength, hardness, toughness, and moderate stiffness, especially with fine grained WC and finely distributed cobalt. WC/Co powder mixture sinters by different methods such as vacuum sintering, microwave sintering and SPS. High pressure high temperature (HPHT) sintering is a proposed method that can result in better distribution of cobalt and avoid undesirable phases by using high pressure, high temperature and very short sintering time. In this study, a powder mixture of WC- 10 wt% Co was sintered by HPHT at 1500 to 1900ºC under a pressure of 7.7 GPa for 2 minutes. Microstructural/structural analyses were performed by SEM/EDS. Hardness and compression test were also done to obtain the effect of sintering parameters. It was found that HPHT sintering method can be used to produce WC/Co hardmetal with low sintering time and high production rate. It was realized that increasing sintering temperature in HTHP sintering method results in increasing density but hardness and compression strength increase by increasing sintering temperature up to 1800 ºC and then decrease.

RESUMO O diboreto de titânio (TiB2) é um material cerâmico que se destaca por sua elevada resistência mecânica, estabilidade química e dureza a altas temperaturas, entretanto, características como baixa sinterabilidade e tenacidade a fratura limitam a atuação deste material em aplicações termomecânicas. Técnicas de sinterização não convencionais como SPS e aditivo de sinterização como AlN e Si3N4 podem reduzir a temperatura de sinterização e aumentar a tenacidade à fratura do TiB2. Neste sentido, o presente trabalho teve como objetivo avaliar a eficiência da técnica de sinterização por plasma pulsado (Spark Plasma Sintering - SPS) no processamento do diboreto de titânio. O nitreto de alumínio foi utilizado como aditivo para reduzir temperatura e tempo de sinterização e facilitar a densificação do TiB2. Os resultados apontam a sinterização por plasma pulsado como uma técnica eficiente na densificação de compósito cerâmico TiB2 - AlN. Elevado grau de densificação foi alcançado mesmo utilizando tempos de sinterização relativamente curto.

ABSTRACT Titanium diboride (TiB2) is a ceramic material that highlight because of its high mechanical resistance, chemical stability and hardness in high temperatures. However, characteristics as low sinterability and fracture toughness restrict its usage on termomechanical applications. Non-conventional sintering techniques as SPS and sintering aid as AlN and Si3N4 can reduce sintering temperature and increase fracture toughness of TiB2. The objective of this work is to evaluate the efficiency of spark plasma sintering (SPS) technique on the manufacturing of titanium diboride. Aluminum nitride (AlN) was used as additive to reduce sintering temperature and time and enhance tib2 densification. The results indicate that spark plasma sintering is an efficient technique in the densification of TiB2 - AlN ceramic composite. High degree of densification was achieved even using relatively short sintering time.