Thermal conductivity of engineered bamboo composites

Here we characterise the thermal properties of engineered bamboo panels produced in Canada, China, and Colombia. Specimens are processed from either Moso or Guadua bamboo into multi-layered panels for use as cladding, flooring or walling. We utilise the transient plane source method to measure their thermal properties and confirm a linear relationship between density and thermal conductivity. Furthermore, we predict the thermal conductivity of a three-phase composite material, as these engineered bamboo products can be described, using micromechanical analysis. This provides important insights on density-thermal conductivity relations in bamboo, and for the first time, enables us to determine the fundamental thermal properties of the bamboo cell wall. Moreover, the density-conductivity relations in bamboo and engineered bamboo products are compared to wood and other engineered wood products. We find that bamboo composites present specific characteristics, for example lower conductivities – particularly at high density – than equivalent timber products. These characteristics are potentially of great interest for low-energy building design. This manuscript fills a gap in existing knowledge on the thermal transport properties of engineered bamboo products, which is critical for both material development and building design.DUS and MCDB thank Mr Robert Cornell (University of Cambridge) for training on thermal conductivity measurement. Special thanks go to Prof Greg Smith and Dr Kate Semple at the University of British Columbia (Department of Wood Science), working on processing of structural bamboo products. This research has been funded by the EPSRC (Grant EP/K023403/1), a Leverhulme Trust Programme Grant, and the Newton Trust.This is the final version of the article. It was first available from Springer via http://dx.doi.org/10.1007/s10853-015-9610-

Thermal conductivity of engineered bamboo composites

Here we characterise the thermal properties of engineered bamboo panels produced in Canada, China, and Colombia. Specimens are processed from either Moso or Guadua bamboo into multi-layered panels for use as cladding, flooring or walling. We utilise the transient plane source method to measure their thermal properties and confirm a linear relationship between density and thermal conductivity. Furthermore, we predict the thermal conductivity of a three-phase composite material, as these engineered bamboo products can be described, using micromechanical analysis. This provides important insights on density-thermal conductivity relations in bamboo, and for the first time, enables us to determine the fundamental thermal properties of the bamboo cell wall. Moreover, the density-conductivity relations in bamboo and engineered bamboo products are compared to wood and other engineered wood products. We find that bamboo composites present specific characteristics, for example lower conductivities—particularly at high density—than equivalent timber products. These characteristics are potentially of great interest for low-energy building design. This manuscript fills a gap in existing knowledge on the thermal transport properties of engineered bamboo products, which is critical for both material development and building design

Co-catalytic absorption layers for controlled laser-induced chemical vapor deposition of carbon nanotubes

The concept of co-catalytic layer structures for controlled laser-induced chemical vapor deposition of carbon nanotubes is established, in which a thin Ta support layer chemically aids the initial Fe catalyst reduction. This enables a significant reduction in laser power, preventing detrimental positive optical feedback and allowing improved growth control. Systematic study of experimental parameters combined with simple thermostatic modeling establishes general guidelines for the effective design of such catalyst/absorption layer combinations. Local growth of vertically aligned carbon nanotube forests directly on flexible polyimide substrates is demonstrated, opening up new routes for nanodevice design and fabrication. © 2014 American Chemical Society

Nomenclature for engineered bamboo

In recent years, there has been a rapid rise in the development of engineered bamboo materials, which have the potential to play an important role as alternatives to conventional building materials. Despite the growing diversity of bamboo products available on the market, the international standardization of both bamboo products and their constituent elements is limited, and a lack of universal nomenclature is recognized as one of the main constraints on developing standards. Similar or identical terminology is used interchangeably to describe different bamboo elements, processes, or products across sectors and continents. In some cases, translated colloquial names are misleading and scientifically inaccurate, which forms a barrier to global collaboration and research, creates ambiguity, and potentially limits trade. The present work aims to address this gap by proposing a set of appropriate terms in English that accurately describe and differentiate between currently produced engineered bamboo products and their constituent elements, accompanied by parallel terms in Chinese and Spanish. From these, new categories of engineered bamboo building materials are proposed for the Harmonized System of product codes. This paper highlights current ambiguities and provides terminology together with clear definitions of the main primary elements, processing steps, and products.</jats:p

Nomenclature for engineered bamboo

In recent years, there has been a rapid rise in the development of engineered bamboo materials, which have the potential to play an important role as alternatives to conventional building materials. Despite the growing diversity of bamboo products available on the market, the international standardization of both bamboo products and their constituent elements is limited, and a lack of universal nomenclature is recognized as one of the main constraints on developing standards. Similar or identical terminology is used interchangeably to describe different bamboo elements, processes, or products across sectors and continents. In some cases, translated colloquial names are misleading and scientifically inaccurate, which forms a barrier to global collaboration and research, creates ambiguity, and potentially limits trade. The present work aims to address this gap by proposing a set of appropriate terms in English that accurately describe and differentiate between currently produced engineered bamboo products and their constituent elements, accompanied by parallel terms in Chinese and Spanish. From these, new categories of engineered bamboo building materials are proposed for the Harmonized System of product codes. This paper highlights current ambiguities and provides terminology together with clear definitions of the main primary elements, processing steps, and products