Multiscale investigations on tracheids and ray. parenchyma cells of spruce

Transcription

1 Multiscale investigations on tracheids and ray Kari Pirkkalainen

2 The people behind the work Kari Pirkkalainen Pekka Saranpää Kirsi Leppänen Prof. Ritva Serimaa Marko Peura Jessica Lucenius Ari Salmi Antti Meriläinen

3 Outline Introduction Experiment Results Conclusions Future aspects

4 Introduction Stem The tracheid Wood tissue Cellulose crystallite Microfibril Macrofibril Cellulose chain

5 Experimental techniques in wood science Atomic scale Nanoscale Sub micron- to Microscopic to micron scale macroscopic Neutron diffraction X-ray diffraction Small-angle neutron scattering Small-angle x-ray scatterring Optical microscopy / light scattering X-ray microtomography Eyeball Electron diffraction X-ray absorption spectroscopy Transmission electron microscopy Scanning electron microscopy

6 Experiment Fertilized stem from Asa, Sweden Samples were taken from 5th, 10th and 17th annual rings. Radial tangential plane Radial longitudinal plane

7 Combined setup for x-ray diffraction and x-ray fluorescence spectroscopy European synchrotron Radiation facility (ESRF) Beamline ID18F Synchrotron storage ring CCD detector Micro-focused X-ray ev. Beam size 2 µm x 15 µm Si(Li) energy dispersive detector

8 Example: x-ray microspot line scan from the 5 th annual ring 1st scan 2nd scan 1000 µm

9 X-ray diffraction L D Cellulose crystallite

10 X-ray fluorescence spectroscopy

11 Line scan ensembles from the 5 th annual ring: XRD Cellulose crystallite width Cellulose crystallite length Fraction of oriented cellulose Mean microfibril angle

12 Line scan ensembles from the 5 th annual ring: XRF Concentration of potassium Concentration of calcium Concentration of manganese Concentration of zinc

13 Results X-ray diffraction Cellulose crystallite width Cellulose crystallite length Fraction of oriented cellulose Mean microfibril angle

14 Results X-ray fluorescence spectroscopy Concentration of potassium Concentration of calcium Concentration of manganese Concentration of zinc

15 Results Microscopic natural variation

16 Conclusions X-ray diffraction and x-ray fluorescence spectroscopy can be used reliably in a combination setup with wooden samples. The fraction of oriented cellulose increased as a function of cambial age, whereas the mean microfibril angle decreased. Nutrient element concentrations of Ca, Mn and Zn decreased as a function of cambial age, whereas the concentration of K increased. The microscopic natural variation of cellulose crystallite width and the fraction of oriented cellulose decreased as a function of cambial age, whereas the natural variation of the mean microfibril angle increased

17 Coming up