scholarly journals Synchrotron X-ray microtomography and 3D image analysis of medium density fiberboard (MDF)

Holzforschung ◽  
2009 ◽  
Vol 63 (5) ◽  
Author(s):  
Thomas Walther ◽  
Heiko Thoemen
Keyword(s):  
Image Analysis ◽  
Structural Information ◽  
Medium Density Fiberboard ◽  
Wood Fiber ◽  
Three Dimensional ◽  
Environmental Scanning Electron Microscopy ◽  
Wall Material ◽  
Medium Density ◽  
Volume Data ◽  
Fiber Network

Abstract The three-dimensional microstructure of a series of laboratory medium density fiberboard (MDF) samples with densities varying from 300 kg m-3 to 1000 kg m-3 was investigated by synchrotron microtomography (SRμCT). After reconstruction and filtering of the volume data, an adapted image analysis was used to extract the structural information about the fiber network at different densities. Information was established on the distribution of intra- and inter-fiber voids, cell-wall material, individual fibers, and fiber bundles. Calculations were performed concerning the surface area towards the ambient void spaces, the number of contacts, and the contact area between selected fibers. Furthermore, the resin distribution on the fibers was investigated and characterized by SRμCT and environmental scanning electron microscopy with stained adhesives. The results presented here allow a new approach to examine the complete wood fiber network of MDFs by automatic image analysis routines.

scholarly journals Three-dimensional geometric measurements of snow microstructural evolution under isothermal conditions

2004 ◽  
Vol 38 ◽  
pp. 39-44 ◽  
Author(s):  
Frédéric Flin ◽  
Jean-Bruno Brzoska ◽  
Bernard Lesaffre ◽  
Cécile Coléou ◽  
Romeu André Pieritz
Keyword(s):  
Image Analysis ◽  
Adaptive Algorithm ◽  
Complex Geometry ◽  
Three Dimensional ◽  
Volume Data ◽  
Tomographic Data ◽  
The Many ◽  
Curvature Distribution ◽  
Curvature Computation

AbstractSnow, from its fall until its full melting, undergoes a structural metamorphism that is governed by temperature and humidity fields. Among the many possible mechanisms that contribute to snow metamorphism, those that depend only on curvature are the most accessible to modelling. In this paper, techniques of volume data analysis adapted to the complex geometry of snow are introduced and then applied to experimental tomographic data coming from the isothermal metamorphism of snow near 0°C. In particular, an adaptive algorithm of curvature computation is described. Present results on the evolution of specific surface area and anisotropy already show that such image-analysis methods are relevant tools for the characterization of real snow microstructures. Moreover, the evolution of the curvature distribution with time provides valuable information for the development of sintering models, in the same way as a possible quantitative calibration of snow-grain coarsening laws.

scholarly journals Effects of nitrogen-phosphorus flame retardants in different forms on the performance of slim-type medium-density fiberboard

BioResources ◽  
2017 ◽  
Vol 12 (4) ◽  
pp. 8014-8029
Author(s):  
Bin Xu ◽  
Weidong Li ◽  
Daowu Tu ◽  
Zhinan Wu ◽  
Changjie Song
Keyword(s):  
Flame Retardants ◽  
Mechanical Performance ◽  
Orthogonal Design ◽  
Medium Density Fiberboard ◽  
Wood Fiber ◽  
Fire Retardant ◽  
National Standard ◽  
Medium Density ◽  
Scanning Calorimetry ◽  
Limiting Oxygen Index

An orthogonal design was used to optimize the process of making slim medium-density fiberboard modified by a nitrogen-phosphorous series of flame retardants. Mechanical performance was the evaluating criterion. Subsequently, the combustion performances of each type of flame retardant, including in states solid, liquid, and their combination with a ratio of 1:1, were investigated to clarify the corresponding fire-retardant mechanism. The results showed that only physical bonding was responsible for connecting the wood fiber with the retardants, according to the Fourier transform infrared spectrum. Catalytic charring, flame retardancy, and the thermal insulation of three types of retardant were solidified by the results of a cone calorimeter (CONE) analysis, thermogravimetric (TG) analysis, and differential scanning calorimetry (DSC), and the mixture of solid and liquid was demonstrated as the primary choice. It was also found that after the mixture of the solid and liquid retardant was added, the limiting oxygen index of the board reached 43.3%, and it met the requirements of the B1 Class in the Chinese National Standard GB/T8624-2012 (2012).

Mechanical and water soaking properties of medium density fiberboard with wood fiber and soybean protein adhesive

2009 ◽  
Vol 100 (14) ◽  
pp. 3556-3562 ◽  
Author(s):  
Xin Li ◽  
Yonghui Li ◽  
Zhikai Zhong ◽  
Donghai Wang ◽  
Jo A. Ratto ◽  
...  
Keyword(s):  
Soybean Protein ◽  
Medium Density Fiberboard ◽  
Wood Fiber ◽  
Medium Density

scholarly journals Three-dimensional Educational Technology for the prevention of accidents caused by falls in the elderly

2021 ◽  
Vol 74 (suppl 5) ◽  
Author(s):  
Rayanne Branco dos Santos Lima ◽  
Rachel Gabriel Bastos Barbosa ◽  
Jamylle Lucas Diniz ◽  
Joyce da Silva Costa ◽  
Marília Braga Marques ◽  
...  
Keyword(s):  
Health Promotion ◽  
Educational Technology ◽  
Medium Density Fiberboard ◽  
Three Dimensional ◽  
The Elderly ◽  
Descriptive Study ◽  
Scale Model ◽  
Medium Density ◽  
Cross Sectional ◽  
Health Promotion Model

ABSTRACT Objective: Evaluate a three-dimensional educational gerontotechnology for the prevention of falls in the elderly at home. Methods: Cross-sectional, descriptive study, involving the Development of gerontotechnology; Evaluation by specialists and target audience, took place in Fortaleza, State of Ceara, Brazil, from June 2017 to October 2018. For the development, it was used the steps adopted in a booklet and the Casa Segura project for the elderly. 16 specialists and 30 elderly participated in the evaluation, using the Health Promotion Model, by Nola Pende. Results: The scale model has an area of 160 cm2, with four rooms made of Medium Density Fiberboard . Specialists consider technology adequate, with a level of compliance of 87.7% IC95% [87,71-88,42]. All the elderly related that the scale model looked their homes, and 13 of them (43.3%) suggested the construction of a backyard, a possible second floor, corridors, and stairs. Conclusion: Gerontotechnology was considered fit to be used in the prevention of falls in the elderly.

Medium-density fiberboard performance as affected by wood fiber acidity, bulk density, and size distribution

2006 ◽  
Vol 40 (8) ◽  
pp. 637-646 ◽  
Author(s):  
Cheng Xing ◽  
S. Y. Zhang ◽  
James Deng ◽  
Bernard Riedl ◽  
Alain Cloutier
Keyword(s):  
Bulk Density ◽  
Size Distribution ◽  
Medium Density Fiberboard ◽  
Wood Fiber ◽  
Medium Density

Two-Dimensional Crystallization of Tetanus Toxin

1985 ◽  
Vol 43 ◽  
pp. 528-529
Author(s):  
Jeffry A. Reidler ◽  
John P. Robinson
Keyword(s):  
Electron Microscopy ◽  
Tetanus Toxin ◽  
Structural Information ◽  
Three Dimensional ◽  
Two Dimensional ◽  
Membrane Interface ◽  
3D Reconstructions ◽  
Cellular Receptors ◽  
Computer Reconstruction ◽  
2D Crystals

We have prepared two-dimensional (2D) crystals of tetanus toxin using procedures developed by Uzgiris and Kornberg for the directed production of 2D crystals of monoclonal antibodies at an antigen-phospholipid monolayer interface. The tetanus toxin crystals were formed using a small mole fraction of the natural receptor, GT1, incorporated into phosphatidyl choline monolayers. The crystals formed at low concentration overnight. Two dimensional crystals of this type are particularly useful for structure determination using electron microscopy and computer image refinement. Three dimensional (3D) structural information can be derived from these crystals by computer reconstruction of photographs of toxin crystals taken at different tilt angles. Such 3D reconstructions may help elucidate the mechanism of entry of the enzymatic subunit of toxins into cells, particularly since these crystals form directly on a membrane interface at similar concentrations of ganglioside GT1 to the natural cellular receptors.

Sign in / Sign up

Export Citation Format

Share Document