Study of stilbene and resin acid content of Scots pine heartwood by electrical impedance spectroscopy (EIS)
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Laura Tomppo
,
Markku Tiitta
Abstract
Scots pine (Pinus sylvestris L.) heartwood samples were measured with electrical impedance spectroscopy (EIS) at frequency range 1 Hz–10 MHz in green and relative humidity (RH) 65% conditioned moisture content (MC) after oven-drying. Complex impedance parameters were studied in relation to the density, moisture, resin acid and stilbene contents. The measurements were conducted in tangential (T) and longitudinal (L) directions with 36 samples in each analysis. For green MC, there were significant correlations between impedance phase angle and contents of stilbenes and resin acids at frequencies below 400 Hz. For the resin acid content, the strongest correlation with phase-angleT was -0.45 (P<0.01) at 100 Hz. Impedance magnitude correlated significantly with MC throughout the frequency range, e.g., at 10 kHz, r was -0.71 (P<0.001) for L-direction. In moisture conditioned state, the correlation between stilbenes and T-measured phase angle was strongest at 250 Hz, (r=-0.56, P<0.001). Equivalent circuit model of two ZARC-Cole elements in series was fitted for the measurements in green MC. Several model parameters correlated with MC (e.g., R1, L r=-0.64, P<0.001), but only one parameter correlated weakly with stilbene content (R2, T r=0.35, P<0.05). The study shows that EIS has a potential for independent determination of resin acid or stilbene contents and MC for green pine heartwood.
©2011 by Walter de Gruyter Berlin Boston
Articles in the same Issue
- Original Papers
- Lignocellulosic biorefinery: process integration of hydrolysis and fermentation (SSF process)
- Study of stilbene and resin acid content of Scots pine heartwood by electrical impedance spectroscopy (EIS)
- Radical scavenging characteristics of condensed tannins from barks of various tree species compared with quebracho wood tannin
- Two-step hydrolysis of nipa (Nypa fruticans) frond as treated by semi-flow hot-compressed water
- Effect of acetic acid addition on chemical conversion of woods as treated by semi-flow hot-compressed water
- Oxidative cleavage of non-phenolic β-O-4 lignin model dimers by an extracellular aromatic peroxygenase
- Surface chemistry of vessel elements by FE-SEM, μ-XPS and ToF-SIMS
- Application of FT-NIR-DR and FT-IR-ATR spectroscopy to estimate the chemical composition of bamboo (Neosinocalamus affinis Keng)
- Chemical modification of lignin assisted by microwave irradiation
- Acidic oxidation of kraft lignin into aromatic monomers catalyzed by transition metal salts
- Effect of Physisporinus vitreus on wood properties of Norway spruce. Part 1: Aspects of delignification and surface hardness
- Effect of Physisporinus vitreus on wood properties of Norway spruce. Part 2: Aspects of microtensile strength and chemical changes
- Mode I critical stress intensity factor of wood and medium-density fiberboard measured by compact tension test
- Effect of oxalic acid pretreatment of wood chips on manufacturing medium-density fiberboard
- Experimental investigation of stress wave propagation in standing trees
- Relationships between mechanical properties of oak timber (Quercus robur L.)
- Estimating mechanical properties and specific gravity for five-year-old Eucalyptus tereticornis having broad moisture content range by NIR spectroscopy
- Effect of morphological variability of incrusted pit membranes on efficiency of transverse compression to improve liquid uptake
- Short Notes
- Performance of biopolymer films with reinforcing cellulose-containing fillers from pine pulp and bark and birch sawdust
- Efficacy of two organic biocides with co-added antioxidants
Articles in the same Issue
- Original Papers
- Lignocellulosic biorefinery: process integration of hydrolysis and fermentation (SSF process)
- Study of stilbene and resin acid content of Scots pine heartwood by electrical impedance spectroscopy (EIS)
- Radical scavenging characteristics of condensed tannins from barks of various tree species compared with quebracho wood tannin
- Two-step hydrolysis of nipa (Nypa fruticans) frond as treated by semi-flow hot-compressed water
- Effect of acetic acid addition on chemical conversion of woods as treated by semi-flow hot-compressed water
- Oxidative cleavage of non-phenolic β-O-4 lignin model dimers by an extracellular aromatic peroxygenase
- Surface chemistry of vessel elements by FE-SEM, μ-XPS and ToF-SIMS
- Application of FT-NIR-DR and FT-IR-ATR spectroscopy to estimate the chemical composition of bamboo (Neosinocalamus affinis Keng)
- Chemical modification of lignin assisted by microwave irradiation
- Acidic oxidation of kraft lignin into aromatic monomers catalyzed by transition metal salts
- Effect of Physisporinus vitreus on wood properties of Norway spruce. Part 1: Aspects of delignification and surface hardness
- Effect of Physisporinus vitreus on wood properties of Norway spruce. Part 2: Aspects of microtensile strength and chemical changes
- Mode I critical stress intensity factor of wood and medium-density fiberboard measured by compact tension test
- Effect of oxalic acid pretreatment of wood chips on manufacturing medium-density fiberboard
- Experimental investigation of stress wave propagation in standing trees
- Relationships between mechanical properties of oak timber (Quercus robur L.)
- Estimating mechanical properties and specific gravity for five-year-old Eucalyptus tereticornis having broad moisture content range by NIR spectroscopy
- Effect of morphological variability of incrusted pit membranes on efficiency of transverse compression to improve liquid uptake
- Short Notes
- Performance of biopolymer films with reinforcing cellulose-containing fillers from pine pulp and bark and birch sawdust
- Efficacy of two organic biocides with co-added antioxidants
