Torrefied biomass‐polypropylene composites

Torrefied almond shells and wood chips were incorporated into polypropylene as fillers to produce torrefied biomass‐polymer composites. The composites were prepared by extrusion and injection molding. Response surface methodology was used to examine the effects of filler concentration, filler size, and lignin factor (relative lignin to cellulose concentration) on the material properties of the composites. The heat distortion temperatures, thermal properties, and tensile properties of the composites were characterized by thermomechanical analysis, differential scanning calorimetry, and tensile tests, respectively. The torrefied biomass composites had heat distortion temperatures of 8–24°C higher than that of neat polypropylene. This was due to the torrefied biomass restricting mobility of polypropylene chains, leading to higher temperatures for deformation. The incorporation of torrefied biomass generally resulted in an increase in glass transition temperature, but did not affect melting temperature. Also, the composites had lower tensile strength and elongation at break values than those of neat polypropylene, indicating weak adhesion between torrefied biomass and polypropylene. However, scanning electron microscopy results did indicate some adhesion between torrefied biomass and polypropylene. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41582.     

Long-Run Trends in Victorian Housing Affordability and First Transition into Homeownership

Over the past two decades housing pathways have become increasingly differentiated between generations, particularly in advanced societies dominated by owner-occupied tenure systems. Demographic transformations caused by aging and falling fertility rates, along with a more volatile economy and a neo-liberal reorientation of governance have combined to restructure housing conditions. Drawing on empirical research in Japan, this paper illustrates the social origins and impact of generation-based differentiations in housing patterns in that country. It considers the housing experiences of three cohorts: baby-boomers, baby-busters and the ‘lost generation’. The contrast of housing pathways between these generations in Japan illustrates the contemporary dynamics of housing and social processes in homeowner societies.     

Creating a Village in Modern Suburbia: Parenthood and Social Capital

Local communities with good stocks of social capital nurture and support the families residing within. This qualitative study explored through the perspectives of mothers, how families with children aged 0–5 years build social capital in newer residential areas in Perth, Western Australia. Parenthood generally increased the desire to connect to one's local community, which activated and enhanced social capital. Two themes appear to drive this desire: an increased need for social support and an increased vested interest in the local community. However, newer residential areas commonly have a lag of community infrastructure needed to provide opportunities for families with young children to interact with other families. Urban planning and community sectors need to coordinate to provide infrastructure and opportunities for families with young children to connect and build social capital within their local communities.     

Book reviews

Whilst there have been numerous categorisations of high-rise buildings according to their function, architectural style, height or structural strategy, historically little work has been undertaken to classify them based on factors affecting their energy performance — their shape and form, façade, attitude to natural lighting, ventilation strategies, etc. These factors have been influenced by regulatory changes, developments in technology and materials, changes in architectural thinking and economic and commercial drivers. Developments such as the New York Zoning Law of 1916, the postwar innovations in curtain wall façades and the energy crises of the 1970s have all impacted on the way tall buildings of the time were designed and operated. These events also had a significant impact on the quantity of energy and the way in which it was consumed in tall buildings of the time. This paper examines the history of energy use in tall buildings, from their origins in North America in the late nineteenth century to the present day. In doing so, it categorises tall buildings into five chronological ‘generations’, based on their energy consumption characteristics.     

Physical and chemical properties of polypyrrole–carbon fiber interphases formed by aqueous electrosynthesis

The properties of carbon fibers modified by aqueous electrochemical synthesis of pyrrole has been determined by using the dynamic contact angle analyzer (DCA), scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR). Electrochemical process parameters such as the initial pyrrole concentration, electrolyte concentration, applied voltage, electrolyte type, and reaction time were systematically varied, and their impact on the polypyrrole–carbon fiber interphases surface free energy and morphology was ascertained. The surface free energies of the polypyrrole–carbon fiber interphases were obtained by using single fiber filaments. SEM analysis of the interphases revealed several distinct surface structures, including smooth, porous, granular, microspheroidal, and leafoidal morphologies. The noncoated but commercially surface oxidized carbon fibers have smooth surface morphology with occasional longitudinal striations. FTIR analysis of the polypyrrole interphases confirmed that the counterions derived from the electrolytes were incorporated into the film. The surface free energies of the electrochemically formed polypyrrole–carbon fiber interphases equivalent to 60–75 dynes/cm, was determined to be up to 40% higher than that for the surface oxidized but unsized carbon fibers equivalent to 50 dynes/cm. This improvement in the surface free energies of the polypyrrole–carbon fiber interphases suggests easy wettability by polymer matrices such as epoxy resin, γ ˜ 47 dynes/cm and, polyimide matrix, γ ˜ 45 dynes/cm. © 1996 John Wiley & Sons, Inc.     

The solution of radiation engineering problems on a transputer-based system

Monte Carlo and finite element methods are numerical techniques used for solving complex problems in reactor physics and radiation shielding. In this paper we are concerned with the implementation of existing research-level codes based on these two methods, written originally for serial computers, on an MIMD transputer-based system. Results and performance of the parallelized codes are presented.     

Global synchronisation in Linda

The paper examines the ‘Distributed Summation’ problem, and its solution in Linda. A number of problems with the current set of primitives are examined, and a new primitive, collect, is proposed.