Accurate bulk density determination of irregularly shaped translucent and opaque aerogels

2016 ◽  
Vol 108 (19) ◽  
pp. 194104 ◽  
Author(s):  
M. P. Petkov ◽  
S. M. Jones
Holzforschung ◽  
2002 ◽  
Vol 56 (5) ◽  
pp. 535-540 ◽  
Author(s):  
A. Macedo ◽  
C. M. P. Vaz ◽  
J. C. D. Pereira ◽  
J. M. Naime ◽  
P. E. Cruvinel ◽  
...  

Summary Wood density measurement is related to several factors that influence wood quality. In this paper, a CT image calibration procedure which allows image quantification in terms of dry bulk density is presented for three different X- and gamma-ray energies (28.3, and 59.5, and 662.0 keV). The mass attenuation coefficients measured for a set of eight wood species did not vary significantly, allowing a single calibration for determination of bulk density of air-dried wood samples at each energy. The equation for bulk density calibration obtained was validated using a second set of twelve wood species. Comparison of bulk density determined by CT images, using the calibration procedure proposed, with values obtained by gravimetric methods, presented a very good linear correlation coefficient (R2=0.94). The main advantage of CT imaging over conventional techniques for wood bulk density determination is that it allows detection and quantification of heterogeneities and internal defects. At the sub-millimetric spatial resolution level, it is possible to identify morphological and structural aspects of wood samples.


Author(s):  
Denisa Cihlarova ◽  
Petr Mondschein ◽  
Silvia Capayova

This paper analyses the destructive and non-destructive methods for checking the degree of compaction of asphalt layers and their multi-criteria evaluation. The data obtained during laying of ACO 11+50 mm thickness was selected for the analysis. The bulk density was determined by using probes Troxler 3440, Troxler 2701 and from the drill cores in these given locations. According to the analysis accuracy, the probe Troxler 2701 used to determine the final degree of compaction of the construction asphalt layer and for the routine control of compaction is not suitable, even though when applying AHP (Analytic Hierarch Process) it was assessed as the second most suitable one.


2019 ◽  
Vol 56 (11) ◽  
pp. 731-746
Author(s):  
R. Peters ◽  
P. Beiss ◽  
S. Lindlohr

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