Xradia nanoXCT-100 tomograph
NanoXCT-100 nanotomograph delivered by Xradia (Concord, California, USA) is an ultra-high resolution 3D CT scanner for 3D visualization of microscopic samples. It uses capillary and zone plate X-ray optics to produce images at a resolution as fine as 50 nm through magnification in both X-ray and visible light wavelength ranges.
The device features switchable 50 nm or 130 nm (MTF 10 %) spatial resolution for samples of 10 µm or 60 µm in diameter, respectively. The typical scan time is 24 h - 48 h per image. Imaging is done with copper k-alpha characteristic peak at 8 keV energy and is best suitable for imaging samples consisting of relatively heavy elements. For example, many minerals are optimal samples for this device, but there has been some work with materials of biological origin, too.
The device works in absorption mode and alternatively in Zernike phase contrast mode.
Materials such as paper and cardboard are made of natural fibres that form a network structure, where individual fibres attach in fibre-fibre bonds. The strength of the network is governed by the strength of the bonds, and one matter that governs the strength of a bond is the area of the region where the two fibres are in contact. A larger contact region usually results in higher bond strength.
In a fibre bond, the two fibres overlap each other but are not in contact with the entire area of the overlapping region. The nanoCT-100 device was used to characterize the area that is bonded as a fraction of the area of the overlapping region. Several individual fibre bonds were imaged, and the bonded area was determined through image analysis. The results in the figures below show that only a small fraction of the total available overlapping area is in contact. Improving the situation such that a larger fraction of the overlapping region would be in contact would therefore increase the bond strength, and that turns into stronger paper and cardboard, or a fibre product of the same strength but made from smaller amount of fibres and therefore consuming less natural resources.
