End-use related physical and mechanical properties of selected fast-growing poplar hybrids (Populus trichocarpa x P-deltoides)

This study focused on physical and mechanical properties of fast-growing poplar clones in relation to potential end uses with high added value. A total of 14 trees from three different clones, all P. trichocarpa x deltoides (T x D) hybrids, were felled in a poplar plantation in Lille (Belgium): six 'Beaupre', four 'Hazendans' and four 'Hoogvorst'. Growth rate was found to have no significant influence on the physical mechanical properties. Although the investigated clones are genetically closely related, important variations in physical and mechanical properties were observed. Specific features such as spatial distribution of tension wood and dimensional stability are the main quality factors. It was concluded that 'Beaupre' is suitable for a wide range of high value added applications, such as plywood or construction wood. 'Hazendans' and 'Hoogvorst' will need adapted technology in processing. Further research is needed to characterize clonally induced variation in properties and to assess adequate processing strategies for multiclonal poplar stands

Micro-CT and mercury intrusion porosimetry characterization of the fabric of roofing slate

The petrological fabric of roofing slate determines the main properties of the slate as a construction material, such as durability and waterproofing. Roofing slates are rocks derived from the low-grade metamorphism of lutites, with a characteristic lepidoblastic fabric. However, little attention by petrologists has been paid to the role of this fabric in the behaviour of roofin slates. This work characterizes the fabric and pore system of two roofing slate varieties from Spain, using two different techniques, each with its advantages and disadvantages: X-ray microtomography, useful to find heterogeneities and mineral inclusions on the slate bulk,and mercury intrusion porosimetry, which defines the pore system. The differentiation of mineral inclusions is very useful for predicting the weathering of a slate, while the definition of the pore system may help to understand how the slate will behave during its service life

The effect of vegetation patterns on Aeolian mass flux at regional scale: a wind tunnel study

Although insight on the effect of vegetation pattern on Aeolian mass transport is essential for re-planting degraded land, only limited knowledge on this effect is available. The objective of this research was to understand the effect of vegetation design on the Aeolian mass flux inside a single land unit and at the borders among land units. A simulation of Atriplex halimus shrubs inside a wind tunnel was made, and sand redistribution was measured after the application of 200-230 seconds wind at a speed of 11 ms-1. The study showed that: 1) sediment maximum transport inside a single land unit is related to the neighboring land units and to the vegetation pattern within both the unit itself and the neighboring land units; 2) the effect of neighboring land units includes the protection effect and the ruling of sediment crossing from one land unit to the neighboring land units; 3) for the designing of re-planting of degraded land the ‘streets’ (zones of erosion areas similar to streets) effect need to be considered; and 4) in addition to the general knowledge needed on the effect of vegetation pattern on the erosion and deposition within an area, it is important to have insight on the redistribution of sediment at small scales upon the aim of the project

Effect of hot boning on colour stability and antioxidant enzyme activities in beef inner and outer biceps femoris

Meat from double-muscled Belgian Blue cattle is characterized by a fast pH decline and slow temperature fall post mortem (pm), which may provoke heat shortening (pH35°C) and negatively affect meat quality, particularly in deeper muscles of the hindquarter. The aim of this study was to investigate the effect of hot boning (within 2 hours pm) on colour and colour stability and on antioxidant enzyme activities (superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px)) in inner and outer Biceps femoris (IBF and OBF) from 7 Belgian Blue young bulls (mean age and carcass weight 22.7 months and 496 kg respectively). The mean duration of heat shortening was 3.4 hours for the cold-boned IBF, whereas there was no period of heat shortening in the hot-boned IBF and in the cold- and hot-boned OBF. The colour L*-value was higher in the cold-boned IBF than OBF (49.3 and 37.6 respectively; P<0.05) resulting in two-toning, whereas there was no significant difference between hot-boned IBF and OBF (33.8 and 34.3 respectively). Concomitantly, the decrease in a*-value and increase in %metmyoglobin over a 7 day display period was higher (P<0.05) for the cold-boned IBF compared to the hot-boned IBF and the cold- and hot-boned OBF. The activities of CAT, GSH-Px and SOD for the IBF and OBF were not significantly different between hot- and cold-boned samples. Hot boning of Biceps femoris in beef carcasses has distinct advantages over cold boning, especially for avoiding heat shortening in the inner part of the muscle and for increasing the colour uniformity in the muscle

3D imaging of clay minerals inside sandstone: pushing the spatial resolution limits using ptychographic tomography

Characterization of microporous, clay-sized particles in natural stone is essential for the understanding of their dynamics. These processes are importand in the fields of oil and gas, groundwater, building stone weathering and soil science. Methods such as X-ray micro-computed tomography is an excellent tool to study features larger than or just under 1 μm, but below the 400 nm limit, the technique falls short. Although destructive methods exists (e.g. FIB/SEM), non-destructive imaging at these very high resolutions has been impossible, until recent developments at synchrotron beam lines. In this study, we use ptychographic tomography at the cSAXS beam line of the PSI in Switzerland, for imaging of clay microstructure at resolutions down to 45 nm, which is the first application of ptychographic tomography for geological samples to our knowledge. During these experiments, relative humidity of the sample’s environment was controlled, in order to asses the influence of R.H. on the analyzed clay minerals. Based on these images, quantitative data on mineral content, porosity, connectivity and behavior under changing environmental conditions of clay mineral clusters was acquired