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  • 1.
    Agnihotri, Swarnima
    et al.
    NTNU Norwegian University of Science and Technology, Norway.
    Johnsen, Ingvild A.
    RISE., Innventia, PFI – Paper and Fiber Research Institute.
    Böe, Maren S.
    NTNU Norwegian University of Science and Technology, Norway.
    Öyaas, Karin
    RISE., Innventia, PFI – Paper and Fiber Research Institute.
    Moe, Størker
    NTNU Norwegian University of Science and Technology, Norway.
    Ethanol organosolv pretreatment of softwood (Picea abies) and sugarcane bagasse for biofuel and biorefinery applications2015Ingår i: Wood Science and Technology, ISSN 0043-7719, E-ISSN 1432-5225, Vol. 49, nr 5, s. 881-896Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Ethanol derived from biomass has the potential to be a renewable transportation fuel that can replace gasoline. This work was carried out to establish an optimized ethanol organosolv pretreatment of Norway spruce (Picea abies) for bioethanol production (63 wt% EtOH, pH ~3.5 in aqueous phase, 170–240 °C, 90 min) utilizing hydrolytic enzymes in the saccharification step. To test the generality of the method, a series of ethanol organosolv pretreatments were also performed on sugarcane bagasse (50 wt% EtOH, pH ~3.5 in aqueous phase, 155–210 °C, 90–120 min). The degree of delignification increased with increasing temperature during pretreatment, and the fastest increase was observed with sugarcane bagasse. The pretreatments were carried out in a batch mode. The maximum degree of delignification of ~65 % was reached at ~235 °C for Norway spruce, while sugarcane bagasse reached ~80 % at ~210 °C. Cellulose was subjected to degradation (5–10 % points) at these temperatures. Subsequent enzymatic hydrolysis (30 FPU/g cellulose, 32 pNPGU/g cellulose, 50 °C, 48 h) of ethanol organosolv-pretreated biomass achieved complete conversion for both raw materials at the highest degrees of delignification.

  • 2.
    Alriksson, Björn
    et al.
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Processum.
    Eskilsson, Martin
    Holmen, Sweden.
    Johansson, Emma
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Processum.
    Lapidot, Shaul
    Melodea, Israel.
    Norström, Markus
    RISE., SP – Sveriges Tekniska Forskningsinstitut.
    Schultz-Eklund, Ola
    Holmen, Sweden .
    Shkedi, Yoram
    Melodea, Israel.
    Svedberg, Anna
    MoRe Research, Sweden.
    Svensson, Stefan
    MoRe Research, Sweden.
    Swerin, Agne
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Kemi Material och Ytor, Material och ytteknik.
    Europe’s first pilot facility for cellulose nanocrystals (CNC)2016Ingår i: Annual Surface and Materials Chemistry Symposium and Materials for tomorrow (ASMCS 2016), 2016Konferensbidrag (Refereegranskat)
  • 3.
    Bjurhager, Ingela
    et al.
    RISE., Innventia.
    Halonen, Helena
    RISE., Innventia.
    Lindfors, Eva Lisa
    RISE., Innventia.
    Iversen, Tommy
    RISE., Innventia.
    Almkvist, Gunnar
    SLU Swedish University of Agricultural Sciences, Sweden.
    Gamstedt, Erik Kristofer
    KTH Royal Institute of Technology, Sweden; University of Uppsala, Sweden.
    Berglund, Lars A.
    KTH Royal Institute of Technology, Sweden.
    State of degradation in archeological oak from the 17th century vasa ship: Substantial strength loss correlates with reduction in (holo)cellulose molecular weight2012Ingår i: Biomacromolecules, ISSN 1525-7797, E-ISSN 1526-4602, nr 8, s. 2521-2527Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In 1628, the Swedish warship Vasa capsized on her maiden voyage and sank in the Stockholm harbor. The ship was recovered in 1961 and, after polyethylene glycol (PEG) impregnation, it was displayed in the Vasa museum. Chemical investigations of the Vasa were undertaken in 2000, and extensive holocellulose degradation was reported at numerous locations in the hull. We have now studied the longitudinal tensile strength of Vasa oak as a function of distance from the surface. The PEG-content, wood density, and cellulose microfibril angle were determined. The molar mass distribution of holocellulose was determined as well as the acid and iron content. A good correlation was found between the tensile strength of the Vasa oak and the average molecular weight of the holocellulose, where the load-bearing cellulose microfibril is the critical constituent. The mean tensile strength is reduced by approximately 40%, and the most affected areas show a reduction of up to 80%. A methodology is developed where variations in density, cellulose microfibril angle, and PEG content are taken into account, so that cell wall effects can be evaluated in wood samples with different rate of impregnation and morphologies.

  • 4.
    Blomqvist, Lars
    et al.
    RISE Research Institutes of Sweden, Bioekonomi och hälsa, Material- och ytdesign.
    Crocetti, Roberto
    KTH Royal Institute of Technology, Sweden.
    Claesson, August
    KTH Royal Institute of Technology, Sweden.
    Ben Osmane, Zakaria
    KTH Royal Institute of Technology, Sweden.
    Ziethén, Rune
    RISE Research Institutes of Sweden, Samhällsbyggnad, Bygg och fastighet.
    Johansson, Marie
    RISE Research Institutes of Sweden, Samhällsbyggnad, Bygg och fastighet.
    EXPERIMENTAL AND NUMERICAL ANALYSES OF A CONNECTION FOR CLT STRUCTURES2023Ingår i: Proceedings of the 2023 World Conference on Timber Engineering (WCTE), Oslo, Norway, 2023, s. 1154-1159Konferensbidrag (Refereegranskat)
    Abstract [en]

    Although building systems made of cross-laminated timber (CLT) have become common in Sweden in the past 20 years and they have developed rapidly during the same period, steps remain to be taken to simplify the assembly of such systems, especially at construction sites. Current construction methods, however, remain labour-intensive and thus show room for improvement.

    This paper describes a novel connection for the assembly of building elements made of CLT. Simple and inexpensive, the connection is fairly insensitive to manufacturing tolerances and enables rapid, more efficient construction than the connections for CLT structures currently used. Test results show the excellent strength and stiffness of the connection, which also allows the replacement of numerous fasteners, including nails and screws, with only a single steel rod. 

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  • 5.
    Blomqvist, Lars
    et al.
    RISE Research Institutes of Sweden, Samhällsbyggnad, Bygg och fastighet.
    Honfi, Daniel
    Ramboll, Denmark.
    Johansson, Marie
    RISE Research Institutes of Sweden, Samhällsbyggnad, Bygg och fastighet.
    Ziethén, Rune
    RISE Research Institutes of Sweden, Samhällsbyggnad, Bygg och fastighet.
    Crocetti, Roberto
    KTH Royal Institute of Technology, Sweden.
    Norén, Joakim
    RISE Research Institutes of Sweden, Samhällsbyggnad, Bygg och fastighet.
    DEVELOPMENT OF NOVEL STRUCTURAL CONNECTIONS –INSPIRATION FROM FURNITURE INDUSTRY2021Ingår i: World Conference onTimber Engineering (WCTE) 2021, Santiago, Chile, 2021Konferensbidrag (Refereegranskat)
    Abstract [en]

    The presented project aims to develop prototypes for building connections inspired by the furniture and interior industry and explore them with representatives from the timber construction industry. The long-term vision is that actors from furniture and building industry together develop a smart system for assembly of building elements, which provide higher precision, faster and more efficient assembly than what is available today. The prototype connectiondeveloped in this project shows that the idea is ripe for full-scale investigation. Laboratory tests showed promising results due to the high failure loads obtained with very high stiffness.

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  • 6.
    Blomqvist, Lars
    et al.
    RISE Research Institutes of Sweden, Bioekonomi och hälsa, Material- och ytdesign.
    Jarnerö, Kirsi
    RISE Research Institutes of Sweden, Samhällsbyggnad, Bygg och fastighet.
    Olsson, Jörgen
    RISE Research Institutes of Sweden, Samhällsbyggnad, Bygg och fastighet.
    Framtidens resurseffektiva KL-trä – en spaning2023Rapport (Övrigt vetenskapligt)
    Abstract [sv]

    Korslimmat trä (KL-trä) för byggnadsändamål är en produkt som togs fram i Centraleuropa i mitten av 1990-talet. Syftet med förstudien är att i samverkan utforska förslag för hur en framtida resurseffektivare KL-träprodukt kan utformas. Målet är att ta fram underlag för utveckling och genera en samling kring frågan. Det finns en medvetenhet för de omvärldsfaktorer som påverkar byggandet med KL-trä. Det finns en ökad efterfrågan på trä i byggsektorn och det finns ett dynamiskt tänkesätt för att ersätta betong med KL-trä. Ökad användning av skogsråvara, global uppvärmning och minskad tillgång via begränsningar i skogsbruk väcker frågor. Vilken råvara har vi i framtiden, vilka trädslag och hur ser tillgången ut? Det resulterande materialet har analyserats utifrån de olika perspektiven som representeras av intressentgrupperna i värdekedjan för byggande med KL-trä. Rapporten avslutas med projektidéer som framkom under arbetet med förstudien.

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    Framtidens resurseffektiva KL-trä – en spaning
  • 7.
    Blomqvist, Lars
    et al.
    RISE Research Institutes of Sweden, Samhällsbyggnad, Bygg och fastighet.
    Ormarsson, Sigurdur
    Linnaeus University, Sweden.
    Ziethén, Rune
    RISE Research Institutes of Sweden, Samhällsbyggnad, Bygg och fastighet.
    Stress distribution in veneers under lamination and simultaneously bending: an experimental and numerical investigation2023Ingår i: Wood Material Science & Engineering, ISSN 1748-0272, E-ISSN 1748-0280, Vol. 18, nr 3, s. 995-1002Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Laminated veneer products (LVPs) are veneers glued together into a predetermined shape. Experimental and numerical investigations were performed under lamination and simultaneously bending of veneer laminate to study the stress distribution in the laminate. Laminates of different thicknesses were made of peeled veneers of European beech. The veneers were coated with adhesive, inserted in a mould which had the shape of a semicircle, and finally pressed at 20°C to a laminate. Two Teflon-polymer films including sensors for measurement of the contact pressure were placed on both sides of the laminate to measure the local contact pressure (contact stress) between the laminate and the mould. At the beginning of the bending process, the contact stresses were locally distributed over the laminate in a similar pattern as in a three-point bending; after the laminate was further bent, the stress distribution rearranged to be as in four-point bending. In the end of the moulding, the local contact stresses increased over the entire laminate and reached a ‘peak-value’ over bent area in the middle part of the mould. A finite-element model was created to study the bending process. Regarding the overall development of the contact stress variations, the experimental and the numerical results agreed.

  • 8.
    Blomqvist, Lars
    et al.
    RISE Research Institutes of Sweden, Samhällsbyggnad, Bygg och fastighet.
    Sterley, Magdalena
    RISE Research Institutes of Sweden, Bioekonomi och hälsa, Material- och ytdesign.
    Formstabilitet i underlägg för dukning2021Rapport (Övrigt vetenskapligt)
    Abstract [sv]

    Formstabilitetsproblematik är ett vanligt problem vid sammanlimning av trä, papper eller dylikt. I denna studie har ett underlägg avsett för dukning undersökts avseende formstabilitet i förhållande till omgivande klimat. Underlägget är uppbyggt av papper, varav vissa med tryck, och en träfiberskiva som sammanlimmats.

    Symmetri i en konstruktion är eftersträvansvärt för hög formstabilitet vilket är känt sedan tidigare. Att ytorna har ett liknande fuktupptag bidrar till symmetrin. Skivor som har en hårdare yta än motstående bör putsas för att skivans bägge ytor ska få ett liknande fuktupptag. Orienteringen av ingående delar i ett laminat kan minska respektive öka asymmetrin om ytorna har olika fuktupptagningsförmåga. Symmetrisk uppbyggnad likväl som symmetriskt fuktupptag är till gagn för hög formstabilitet.

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  • 9.
    Blomqvist, Lars
    et al.
    RISE Research Institutes of Sweden, Bioekonomi och hälsa, Material- och ytdesign.
    Sterley, Magdalena
    RISE Research Institutes of Sweden, Bioekonomi och hälsa, Material- och ytdesign.
    Influence of different pressing parameters on urea-formaldehyde adhesive-bond strength in laminated veneer products2022Rapport (Övrigt vetenskapligt)
    Abstract [en]

     The aim of the present study was to investigate the relationships between contact pressure, temperature, hardener content and pressing time fixed at different levels and the strength of the UF adhesive bond, in order to develop a model to predicting the bonding strength. Bond strength was measured with the Adhesive Bonding Evaluation System, and a linear model for predicting adhesive bond strength using four independent variables was developed (R2 = 0.75). The strongest parameter was pressing time, followed by hardener content and temperature, all of which explained variation in bond strength at the same level. Pressure had no significant influence on the bond strength.

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  • 10.
    Blomqvist, Lars
    et al.
    RISE Research Institutes of Sweden, Samhällsbyggnad.
    Sterley, Magdalena
    RISE Research Institutes of Sweden, Bioekonomi och hälsa.
    Influence of pressure on bond-line shear strength in laminated veneer products2022Ingår i: Wood Material Science & Engineering, ISSN 1748-0272, E-ISSN 1748-0280, Vol. 17, nr 6, s. 1020-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this study, the bond-line strength of different bonding pressure of veneers in dry (9% moisturecontent) and wet (immersed in water) conditions was investigated. The results show that peeledEuropean beech veneers need approximately 0.5– 1.2 MPa pressure to achieve a proper bond-linewhen a urea-formaldehyde adhesive was used. The pressure variation within this range did notsignificantly affect the strength of the dry veneer, but the strength of the wet veneers decreasedas the bonding pressure increased. The type of failure varied, especially for the wet veneers. Athigh pressure, the wood were stronger than the cohesive strength of the adhesive and thestrength of the adhesion between the adhesive and the wood. High pressure, however, caused acompression of the bond-line and resulted in a lack of adhesion.

  • 11.
    Blomqvist, Lars
    et al.
    RISE - Research Institutes of Sweden (2017-2019), Samhällsbyggnad, Byggteknik.
    Sterley, Magdalena
    RISE - Research Institutes of Sweden (2017-2019), Bioekonomi, Biobaserade material.
    Ormarsson, Sigurdur
    Linnaeus University, Sweden.
    Impact of surface pressure on the shape stability of laminated veneer products2019Ingår i: Proceedings of the 15th Annual Meeting of the Northern European Network for Wood Science and Engineering WSE 2019 / [ed] Maria Fredriksson, Lund: Lund University , 2019, s. 164-166Konferensbidrag (Övrigt vetenskapligt)
    Ladda ner fulltext (pdf)
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  • 12.
    Brischke, C.
    et al.
    University of Goettingen, Germany.
    Westin, Mats
    RISE Research Institutes of Sweden, Bioekonomi och hälsa, Material- och ytdesign.
    Suttie, Ed
    Building Research Establishment, UK.
    Modeling the material resistance of wood—part 2: Validation and optimization of the meyer-veltrup model2021Ingår i: Forests, ISSN 1999-4907, E-ISSN 1999-4907, Vol. 12, nr 5, artikel-id 576Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Service life planning with timber requires reliable models for quantifying the effects of exposure-related parameters and the material-inherent resistance of wood against biotic agents. The Meyer-Veltrup model was the first attempt to account for inherent protective properties and the wetting ability of wood to quantify resistance of wood in a quantitative manner. Based on test data on brown, white, and soft rot as well as moisture dynamics, the decay rates of different untreated wood species were predicted relative to the reference species of Norway spruce (Picea abies). The present study aimed to validate and optimize the resistance model for a wider range of wood species including very durable species, thermally and chemically modified wood, and preservative treated wood. The general model structure was shown to also be suitable for highly durable materials, but previously defined maximum thresholds had to be adjusted (i.e., maximum values of factors accounting for wetting ability and inherent protective properties) to 18 instead of 5 compared to Norway spruce. As expected, both the enlarged span in durability and the use of numerous and partly very divergent data sources (i.e., test methods, test locations, and types of data presentation) led to a decrease in the predictive power of the model compared to the original. In addition to the need to enlarge the database quantity and improve its quality, in particular for treated wood, it might be advantageous to use separate models for untreated and treated wood as long as the effect of additional impact variables (e.g., treatment quality) can be accounted for. Nevertheless, the adapted Meyer-Veltrup model will serve as an instrument to quantify material resistance for a wide range of wood-based materials as an input for comprehensive service life prediction software. © 2021 by the authors.

  • 13.
    Brischke, C.
    et al.
    University of Goettingen, Germany.
    Westin, Mats
    RISE Research Institutes of Sweden, Bioekonomi och hälsa, Material- och ytdesign.
    Suttie, Ed
    Building Research Establishment, UK.
    Modelling the material resistance of wood—Part 3: Relative resistance in above and in ground situations—Results of a global survey2021Ingår i: Forests, ISSN 1999-4907, E-ISSN 1999-4907, Vol. 12, nr 5, artikel-id 590Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Durability-based designs with timber require reliable information about the wood properties and how they affect its performance under variable exposure conditions. This study aimed at utilizing a material resistance model (Part 2 of this publication) based on a dose–response approach for predicting the relative decay rates in above-ground situations. Laboratory and field test data were, for the first time, surveyed globally and used to determine material-specific resistance dose values, which were correlated to decay rates. In addition, laboratory indicators were used to adapt the material resistance model to in-ground exposure. The relationship between decay rates in-and above-ground, the predictive power of laboratory indicators to predict such decay rates, and a method for implementing both in a service life prediction tool, were established based on 195 hardwoods, 29 softwoods, 19 modified timbers, and 41 preservative-treated timbers. © 2021 by the authors..

  • 14. Chacha, N.
    et al.
    Toven, K
    RISE., Innventia, PFI – Paper and Fiber Research Institute.
    Mtui, G
    Katima, J
    Mrema, G
    Steam Pretreatment of Pine (Pinus patula) wood residue for the production of reducing sugars2011Ingår i: Cellulose Chemistry and Technology, ISSN 0576-9787, Vol. 45, s. 495-501Artikel i tidskrift (Refereegranskat)
  • 15.
    Chang, Shan-Shan
    et al.
    Université Montpellier, France.
    Salmen, Lennart
    RISE., Innventia.
    Olsson, Anne-Mari
    RISE., Innventia.
    Clair, Bruno
    Université Montpellier, France.
    Deposition and organisation of cell wall polymers during maturation of poplar tension wood by FTIR microspectroscopy2014Ingår i: Planta, ISSN 0032-0935, E-ISSN 1432-2048, Vol. 239, nr 1, s. 243-254Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    To advance our understanding of the formation of tension wood, we investigated the macromolecular arrangement in cell walls by Fourier transform infrared microspectroscopy (FTIR) during maturation of tension wood in poplar (Populus tremula x P. alba, clone INRA 717-1B4). The relation between changes in composition and the deposition of the G-layer in tension wood was analysed. Polarised FTIR measurements indicated that in tension wood, already before G-layer formation, a more ordered structure of carbohydrates at an angle more parallel to the fibre axis exists. This was clearly different from the behaviour of opposite wood. With the formation of the S2 layer in opposite wood and the G-layer in tension wood, the orientation signals from the amorphous carbohydrates like hemicelluloses and pectins were different between opposite wood and tension wood. For tension wood, the orientation for these bands remains the same all along the cell wall maturation process, probably reflecting a continued deposition of xyloglucan or xylan, with an orientation different to that in the S2 wall throughout the whole process. In tension wood, the lignin was more highly oriented in the S2 layer than in opposite wood.

  • 16.
    Chen, Z. -Q.
    et al.
    SLU Swedish University of Agricultural Sciences, Sweden.
    Abramowicz, K.
    Umeå University, Sweden.
    Raczkowski, R.
    SLU Swedish University of Agricultural Sciences, Sweden.
    Ganea, S.
    SLU Swedish University of Agricultural Sciences, Sweden.
    Wu, H. X.
    SLU Swedish University of Agricultural Sciences, Sweden; CSIRO Commonwealth Scientific and Industrial Research Organisation, Australia.
    Lundqvist, Sven-Olof
    RISE., Innventia.
    Mörling, T.
    SLU Swedish University of Agricultural Sciences, Sweden.
    De Luna, S. S.
    Umeå University, Sweden.
    Garci­a Gil, M. R.
    SLU Swedish University of Agricultural Sciences, Sweden.
    Mellerowicz, E. J.
    SLU Swedish University of Agricultural Sciences, Sweden.
    Method for accurate fiber length determination from increment cores for large-scale population analyses in Norway spruce2016Ingår i: Holzforschung, ISSN 0018-3830, E-ISSN 1437-434X, Vol. 70, nr 9, s. 829-838Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Fiber (tracheid) length is an important trait targeted for genetic and silvicultural improvement. Such studies require large-scale non-destructive sampling, and accurate length determination. The standard procedure for non-destructive sampling is to collect increment cores, singularize their cells by maceration, measure them with optical analyzer and apply various corrections to suppress influence of non-fiber particles and cut fibers, as fibers are cut by the corer. The recently developed expectation-maximization method (EM) not only addresses the problem of non-fibers and cut fibers, but also corrects for the sampling bias. Here, the performance of the EM method has been evaluated by comparing it with length-weighing and squared length-weighing, both implemented in fiber analyzers, and with microscopy data for intact fibers, corrected for sampling bias, as the reference. This was done for 12-mm increment cores from 16 Norway spruce (Picea abies (L.) Karst) trees on fibers from rings 8-11 (counted from pith), representing juvenile wood of interest in breeding programs. The EM-estimates provided mean-fiber-lengths with bias of only +2.7% and low scatter. Length-weighing and length2-weighing gave biases of-7.3% and +9.3%, respectively, and larger scatter. The suggested EM approach constitutes a more accurate non-destructive method for fiber length (FL) determination, expected to be applicable also to other conifers.

  • 17.
    Chen, Zhi-Qiang
    et al.
    SLU Swedish University of Agricultural Sciences, Sweden.
    Karlsson, Bo
    Skogforsk, Sweden.
    Lundqvist, Sven-Olof
    RISE., Innventia.
    Garci­a Gil, María Rosario
    SLU Swedish University of Agricultural Sciences, Sweden.
    Olsson, Lars
    RISE., Innventia.
    Wu, Harry X.
    CSIRO Commonwealth Scientific and Industrial Research Organisation, Australia.
    Estimating solid wood properties using Pilodyn and acoustic velocity on standing trees of Norway spruce2015Ingår i: Annals of Forest Science, ISSN 1286-4560, E-ISSN 1297-966X, Vol. 72, nr 4, s. 499-508Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Key message: Strong genetic correlations were observed between Pilodyn measurement and wood density, and between acoustic velocity and MFA. Combination of Pilodyn penetration and acoustic velocity measurements from standing trees can provide reliable prediction of stiffness of Norway spruce for breeding selection.

    Context: Traditional methods for the estimation of solid wood quality traits of standing tree such as wood density, microfibril angle (MFA), and modulus of elasticity (MOE) are time-consuming and expensive, which render them unsuitable for rapidly screening a large number of trees in tree breeding programs.

    Aim: This study aims to evaluate the suitability of using Pilodyn penetration and acoustic velocity (nondestructive evaluation) to assess wood density, MFA, and MOE for Norway spruce.

    Methods: Pilodyn penetration and Hitman acoustic velocity, as well as wood density, MFA, and MOE using benchmark SilviScan were measured on 5618 standing trees of 524 open-pollinated families in two 21-year-old Norway spruce (Picea abies) progeny trials in southern Sweden.

    Results: Strong genetic correlations were observed between Pilodyn measurement and wood density (rg = −0.96), and between acoustic velocity and MFA (rg = −0.94). Combination of Pilodyn penetration and Hitman acoustic velocity measurements (Formula presented.) obtained from standing trees showed a genetic correlation with benchmark MOE of 0.99. This combined MOE(Formula presented.) had higher selection efficiency for benchmark MOE (92 %) compared to 58–60 % using acoustic velocity alone and 78 % using Pilodyn penetration alone.

    Conclusion: Combination of Pilodyn penetration with Hitman acoustic velocity provided very high selection efficiency for the three most important quality traits for wood mechanical properties in Norway spruce.

  • 18.
    Chen, Zhi-Qiang
    et al.
    SLU Swedish University of Agricultural Sciences, Sweden.
    Karlsson, Bo
    Skogforsk, Sweden.
    Mörling, Tommy
    SLU Swedish University of Agricultural Sciences, Sweden.
    Olsson, Lars
    RISE., Innventia.
    Mellerowicz, Ewa J.
    SLU Swedish University of Agricultural Sciences, Sweden.
    Wu, Harry X.
    SLU Swedish University of Agricultural Sciences, Sweden; CSIRO Commonwealth Scientific and Industrial Research Organisation, Australia.
    Lundqvist, Sven-Olof
    RISE., Innventia.
    Gil, María Rosario García
    SLU Swedish University of Agricultural Sciences, Sweden.
    Genetic analysis of fiber dimensions and their correlation with stem diameter and solid-wood properties in Norway spruce2016Ingår i: Tree Genetics & Genomes, ISSN 1614-2942, E-ISSN 1614-2950, Vol. 12, nr 6, artikel-id 123Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Adverse genetic correlations between growth traits and solid-wood, as well as fiber traits are a concern in conifer breeding programs. To evaluate the impact of selection for growth and solid-wood properties on fiber dimensions, we investigated the inheritance and efficiency of early selection for different wood-fiber traits and their correlations with stem diameter, wood density, modulus of elasticity (MOE), and microfibril angle (MFA) in Norway spruce (Picea abies L). The study was based on two large open-pollinated progeny trials established in southern Sweden in 1990 with material from 524 families comprising 5618 trees. Two increment cores were sampled from each tree. Radial variations from pith to bark were determined for rings 3–15 with SilviScan for fiber widths in the radial (RFW) and tangential (TFW) direction, fiber wall thickness (FWT), and fiber coarseness (FC). Fiber length (FL) was determined for rings 8–11. Heritabilities based on rings 8–11 using joint-site data were moderate to high (0.24–0.51) for all fiber-dimension traits. Heritabilities based on stem cross-sectional averages varied from 0.34 to 0.48 and reached a plateau at rings 6–9. The “age-age” genetic correlations for RFW, TFW, FWT, and FC cross-sectional averages at a particular age with cross-sectional averages at ring 15 reached 0.9 at rings 4–7. Our results indicated a moderate to high positive genetic correlation for density and MOE with FC and FWT, moderate and negative with RFW, and low with TFW and FL. Comparison of several selection scenarios indicated that the highest profitability is reached when diameter and MOE are considered jointly, in which case, the effect on any fiber dimension is negligible. Early selection was highly efficient from ring 5 for RFW and from rings 8–10 for TFW, FWT, and FC.

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  • 19. Dammström, S.
    et al.
    Salmen, Lennart
    RISE., STFI-Packforsk.
    Gatenholm, P.
    On the interactions between cellulose and xylan, a biomimetic simulation of the hardwood cell wall2009Ingår i: BioResources, ISSN 1930-2126, E-ISSN 1930-2126, Vol. 4, nr 1, s. 3-14Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The plant cell wall exhibits a hierarchical structure, in which the organization of the constituents on different levels strongly affects the mechanical properties and the performance of the material. In this work, the interactions between cellulose and xylan in a model system consisting of a bacterial cellulose/glucuronoxylan (extracted from aspen, Populus tremula) have been studied and compared to that of a delignified aspen fiber material. The properties of the materials were analyzed using Dynamical Mechanical Analysis (DMA) with moisture scans together with dynamic Infra Red -spectroscopy at dry and humid conditions. The results showed that strong interactions existed between the cellulose and the xylan in the aspen holocellulose. The same kinds of interactions were seen in a water-extracted bacterial cellulose/xylan composite, while unextracted material showed the presence of xylan not interacting with the cellulose. Based on these findings for the model system, it was suggested that there is in hardwood one fraction of xylan that is strongly associated with the cellulose, taking a similar role as glucomannan in softwood.

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  • 20.
    De Magistris, Federica
    et al.
    RISE., STFI-Packforsk.
    Salmen, Lennart
    RISE., STFI-Packforsk.
    Finite element modelling of wood cell deformation transverse to the fibre axis2008Ingår i: Nordic Pulp & Paper Research Journal, ISSN 0283-2631, E-ISSN 2000-0669, Vol. 23, nr 2, s. 240-246Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Modelling of wet wood under compression and combined shear and compression load was performed to simulate the mechanical pulping of wood chips in refiners. Experiments have shown that the wet fibre network exhibit two different deformation modes; an S-shape mode associated with compression and a brick-shape mode associated with combined shear and compression. To study the factors governing the mechanical behaviour of the fibre network a material model with the characteristics originating from the properties of the wood polymers was developed and was used in a three-dimensional finite element analysis. The effects of material properties were investigated by comparing models with anisotropic one-layer cell walls and orthotropic multi-layer cell walls. The deformation achieved both under compression and under combined shear and compression was found to be similar independent of the material constants used or the number of layers of the cells walls. This implies that the most important factor governing the deformation pattern of the fibre network is the cell structure itself.

  • 21.
    Dedic, D.
    et al.
    RISE., Innventia.
    Iversen, T.
    RISE., Innventia.
    Sandberg, T.
    Ek, M.
    Chemical analysis of wood extractives and lignin in the oak wood of the 380 year old Swedish warship vasa2011Konferensbidrag (Refereegranskat)
  • 22.
    Dedic, Dina
    et al.
    KTH Royal Institute of Technology, Sweden.
    Iversen, Tommy
    RISE., Innventia. KTH Royal Institute of Technology, Sweden.
    Ek, Monica
    KTH Royal Institute of Technology, Sweden.
    Cellulose degradation in the Vasa - the role of acids and rust2013Ingår i: Studies in Conservation, ISSN 0039-3630, E-ISSN 2047-0584, Vol. 58, nr 4, s. 308-313, artikel-id 40105Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The oak timbers of the Swedish warship Vasa are deteriorating. High amounts of oxalic acid have been found along with a low pH and low molecular weight cellulose deep in the wood timbers. The iron-rich surface wood differs from the interior wood in that it displays higher pH and cellulose with higher molecular weight. The objective of this study was to determine why there is a difference in cellulose degradation, pH, and oxalic acid amount between the surface region and the interior of the Vasa timbers. Analysis of cellulose weight average molecular weight by size exclusion chromatography was performed, as well as quantification of oxalic acid and iron by high-performance anion exchange chromatography and atomic emission spectroscopy, respectively. It was found that a decrease in iron content coincides with an increase in oxalic acid concentration and a drop in pH at a certain depth from the wood surface. When iron-rich surface wood samples from the Vasa were mixed with an aqueous solution of oxalic acid, a fast increase of pH over time was observed. Neither interior wood poor in iron nor the fresh oak reference showed the same neutralizing effect during the time of measurement. This indicates that the presence of iron (rust) causes a neutralization of the wood, through the formation of iron(III) oxalato complexes, thus protecting the wood from oxalic acid hydrolysis. This effect was not observed to the same extent for other acids observed in Vasa wood (sulfuric, formic, glycolic, and acetic acids).

  • 23.
    Eder, Michaela
    et al.
    Max-Planck-Institute of Colloids and Interfaces, Germany.
    Arnould, Olivier
    Université Montpellier, France.
    Dunlop, John W.C.
    Max-Planck-Institute of Colloids and Interfaces, Germany.
    Hornatowska, Joanna
    RISE., Innventia.
    Salmen, Lennart
    RISE., Innventia.
    Experimental micromechanical characterisation of wood cell walls2013Ingår i: Wood Science and Technology, ISSN 0043-7719, E-ISSN 1432-5225, nr 1, s. 163-182Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The properties of wood and wood-based materials are strongly dependent on the properties of the fibres, that is, the cell wall properties. It is thus highly important to be able to mechanically characterise cell walls in order to understand structure-property relationships. This article gives a brief overview of the state of the art in experimental techniques to characterise the mechanical properties of wood at both the level of the single cell and that of the cell wall. Challenges, opportunities, drawbacks and limitations of single fibre tensile tests and nanoindentation are discussed with respect to the wood material properties.

  • 24.
    Engelund, Emil Tang
    et al.
    Danish Technological Institute, Denmark; DTU Technical University of Denmark, Denmark.
    Salmen, Lennart
    RISE., Innventia.
    Tensile creep and recovery of Norway spruce influenced by temperature and moisture2012Ingår i: Holzforschung, ISSN 0018-3830, E-ISSN 1437-434X, Vol. 66, nr 8, s. 959-965Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The time-dependent mechanical behaviour (TDMB) of wood is important when using the material for structural purposes. Recently, a new method for predicting the TDMB by numerical modelling was established based on the assumption that TDMB is caused by the sliding of the microfibrils past each other. In this study, the TDMB is examined via creep experiments on small specimens of Norway spruce latewood. The results of these are compared with results from numerical modelling. The experiments include results at two levels of moisture content and three levels of temperature, enabling an investigation of these two climatic factors on TDMB of wood. It was found that the mechanical response of wood tissue is the sum of responses from both tracheids and middle lamella, with only the previous being reversible. The effect of moisture and temperature differed in that the latter affected the elastic and time-dependent responses equally. Moisture, on the other hand, reduced both the elastic properties and the activation energy barrier for sliding of the microfibrils, but furthermore changed the microfibril angle of the sample as a result of swelling. Hereby, moisture had a larger effect on the time-dependent response than the elastic. All of these effects were predicted by numerical modelling.

  • 25.
    Escamez, S.
    et al.
    SLU Swedish University of Agricultural Sciences, Sweden; Umeå University, Sweden.
    Terryn, C.
    Université de Reims Champagne Ardenne, France.
    Gandla, M. L.
    Umeå University, Sweden.
    Yassin, Zakiya
    RISE Research Institutes of Sweden, Samhällsbyggnad, Bygg och fastighet.
    Scheepers, Gerhard
    RISE Research Institutes of Sweden, Samhällsbyggnad, Bygg och fastighet.
    Näsholm, T.
    SLU Swedish University of Agricultural Sciences, Sweden.
    Sundman, O.
    Umeå University, Sweden.
    Jönsson, L. J.
    Umeå University, Sweden.
    Lundberg-Felten, J.
    SLU Swedish University of Agricultural Sciences, Sweden.
    Tuominen, H.
    SLU Swedish University of Agricultural Sciences, Sweden.
    Niittylä, T.
    SLU Swedish University of Agricultural Sciences, Sweden.
    Paës, G.
    Université de Reims Champagne Ardenne, France.
    Fluorescence Lifetime Imaging as an in Situ and Label-Free Readout for the Chemical Composition of Lignin2021Ingår i: ACS Sustainable Chemistry and Engineering, E-ISSN 2168-0485, Vol. 9, nr 51Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Naturally fluorescent polymeric molecules such as collagen, resilin, cutin, suberin, or lignin can serve as renewable sources of bioproducts. Theoretical physics predicts that the fluorescence lifetime of these polymers is related to their chemical composition. We verified this prediction for lignin, a major structural element in plant cell walls that form woody biomass. Lignin is composed of different phenylpropanoid units, and its composition affects its properties, biological functions, and the utilization of wood biomass. We carried out fluorescence lifetime imaging microscopy (FLIM) measurements of wood cell wall lignin in a population of 90 hybrid aspen trees genetically engineered to display differences in cell wall chemistry and structure. We also measured the wood cell wall composition by classical analytical methods in these trees. Using statistical modeling and machine learning algorithms, we identified parameters of fluorescence lifetime that predict the content of S-type and G-type lignin units, the two main types of units in the lignin of angiosperm (flowering) plants. In a first step toward tailoring lignin biosynthesis toward improvement of woody biomass feedstocks, we show how FLIM can reveal the dynamics of lignin biosynthesis in two different biological contexts, including in vivo while lignin is being synthesized in the walls of living cells. © 2021 The Authors.

  • 26.
    Escamez, Sacha
    et al.
    Umeå University, Sweden.
    Latha Gandla, Madhavi
    Umeå University, Sweden.
    Derba-Maceluch, Marta
    SLU Swedish University of Agricultural Sciences, Sweden.
    Lundqvist, Sven-Olof
    RISE - Research Institutes of Sweden (2017-2019), Bioekonomi. RISE., Innventia.
    Mellerowicz, Ewa J.
    SLU Swedish University of Agricultural Sciences, Sweden.
    Jönsson, Leif J.
    Umeå University, Sweden.
    Tuominen, Hannele
    Umeå University, Sweden.
    A collection of genetically engineered Populus trees reveals wood biomass traits that predict glucose yield from enzymatic hydrolysis2017Ingår i: Scientific Reports, E-ISSN 2045-2322, Vol. 7, nr 1, artikel-id 15798Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Wood represents a promising source of sugars to produce bio-based renewables, including biofuels. However, breaking down lignocellulose requires costly pretreatments because lignocellulose is recalcitrant to enzymatic saccharification. Increasing saccharification potential would greatly contribute to make wood a competitive alternative to petroleum, but this requires improving wood properties. To identify wood biomass traits associated with saccharification, we analyzed a total of 65 traits related to wood chemistry, anatomy and structure, biomass production and saccharification in 40 genetically engineered Populus tree lines. These lines exhibited broad variation in quantitative traits, allowing for multivariate analyses and mathematical modeling. Modeling revealed that seven wood biomass traits associated in a predictive manner with saccharification of glucose after pretreatment. Four of these seven traits were also negatively associated with biomass production, suggesting a trade-off between saccharification potential and total biomass, which has previously been observed to offset the overall sugar yield from whole trees. We therefore estimated the "total-wood glucose yield" (TWG) from whole trees and found 22 biomass traits predictive of TWG after pretreatment. Both saccharification and TWG were associated with low abundant, often overlooked matrix polysaccharides such as arabinose and rhamnose which possibly represent new markers for improved Populus feedstocks.

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  • 27.
    Escamez, Sacha
    et al.
    Umeå University, Sweden.
    Robinson, Kathryn
    Umeå University, Sweden.
    Luomaranta, Mikko
    Umeå University, Sweden.
    Gandla, Madhavi
    Umeå University, Sweden.
    Mähler, Niklas
    Umeå University, Sweden.
    Yassin, Zakiya
    RISE Research Institutes of Sweden, Samhällsbyggnad, Bygg och fastighet.
    Grahn, Thomas
    RISE Research Institutes of Sweden, Bioekonomi och hälsa, Massa, papper och förpackningar.
    Scheepers, Gerhard
    RISE Research Institutes of Sweden, Samhällsbyggnad, Bygg och fastighet.
    Stener, Lars-Göran
    Forestry Research Institute of Sweden, Sweden.
    Jansson, Stefan
    Umeå University, Sweden.
    Jönsson, eif
    Umeå University, Sweden.
    Street, N. R.
    Umeå University, Sweden.
    Tuominen, Hannele
    Umeå University, Sweden; SLU Swedish University of Agricultural Sciences, Sweden.
    Genetic markers and tree properties predicting wood biorefining potential in aspen (Populus tremula) bioenergy feedstock2023Ingår i: Biotechnology for Biofuels and Bioproducts, E-ISSN 2731-3654, Vol. 16, nr 1, artikel-id 65Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background: Wood represents the majority of the biomass on land and constitutes a renewable source of biofuels and other bioproducts. However, wood is recalcitrant to bioconversion, raising a need for feedstock improvement in production of, for instance, biofuels. We investigated the properties of wood that affect bioconversion, as well as the underlying genetics, to help identify superior tree feedstocks for biorefining. Results: We recorded 65 wood-related and growth traits in a population of 113 natural aspen genotypes from Sweden (https://doi.org/10.5061/dryad.gtht76hrd). These traits included three growth and field performance traits, 20 traits for wood chemical composition, 17 traits for wood anatomy and structure, and 25 wood saccharification traits as indicators of bioconversion potential. Glucose release after saccharification with acidic pretreatment correlated positively with tree stem height and diameter and the carbohydrate content of the wood, and negatively with the content of lignin and the hemicellulose sugar units. Most of these traits displayed extensive natural variation within the aspen population and high broad-sense heritability, supporting their potential in genetic improvement of feedstocks towards improved bioconversion. Finally, a genome-wide association study (GWAS) revealed 13 genetic loci for saccharification yield (on a whole-tree-biomass basis), with six of them intersecting with associations for either height or stem diameter of the trees. Conclusions: The simple growth traits of stem height and diameter were identified as good predictors of wood saccharification yield in aspen trees. GWAS elucidated the underlying genetics, revealing putative genetic markers for bioconversion of bioenergy tree feedstocks. © 2023, The Author(s).

  • 28. Fackler, K.
    et al.
    Stevanic, Jasna S.
    RISE., Innventia.
    Ters, T.
    Hinterstoisser, B.
    Schwanninger, M.
    Salmen, Lennart
    RISE., Innventia.
    Localisation and characterisation of incipient brown-rot decay within spruce wood cell walls using FT-IR imaging microscopy2010Ingår i: Enzyme and microbial technology, ISSN 0141-0229, E-ISSN 1879-0909, Vol. 47, nr 6, s. 257-267Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Spruce wood that had been degraded by brown-rot fungi (Gloeophyllum trabeum or Poria placenta) exhibiting mass losses up to 16% was investigated by transmission Fourier transform infrared (FT-IR) imaging microscopy. Here the first work on the application of FT-IR imaging microscopy and multivariate image analysis of fungal degraded wood is presented and the first report on the spatial distribution of polysaccharide degradation during incipient brown-rot of wood. Brown-rot starts to become significant in the outer cell wall regions (middle lamellae, primary cell walls, and the outer layer of the secondary cell wall S1). This pattern was detected even in a sample with non-detectable mass loss. Most significant during incipient decay was the cleavage of glycosidic bonds, i.e. depolymerisation of wood polysaccharides and the degradation of pectic substances. Accordingly, intramolecular hydrogen bonding within cellulose was reduced, while the presence of phenolic groups increased.

  • 29. Fackler, K.
    et al.
    Stevanic, J.S.
    RISE., Innventia.
    Ters, T.
    Hinterstoisser, B.
    Schwanninger, M.
    Salmen, L.
    RISE., Innventia.
    FT-IR imaging microscopy to localise and characterise simultaneous and selective white-rot decay within spruce wood cells2011Ingår i: Holzforschung, ISSN 0018-3830, E-ISSN 1437-434X, nr 3, s. 411-420Artikel i tidskrift (Refereegranskat)
  • 30. Franceschini, T.
    et al.
    Lundqvist, S.-O.
    RISE., Innventia.
    Bontemps, J.-D.
    Grahn, T.
    RISE., Innventia.
    Olsson, L.
    RISE., Innventia.
    Evans, R.
    Leban, J.-M.
    Empirical models for radial and tangential fibre width in tree rings of Norway spruce in north-western Europe2012Ingår i: Holzforschung, ISSN 0018-3830, E-ISSN 1437-434X, nr 2, s. 219-230Artikel i tidskrift (Refereegranskat)
  • 31.
    Funk, Peter
    et al.
    RISE Research Institutes of Sweden, Samhällsbyggnad, Bygg och fastighet.
    Lycken, Anders
    RISE Research Institutes of Sweden, Samhällsbyggnad, Bygg och fastighet.
    Värde- eller volymoptimering av sidobräder2022Rapport (Övrigt vetenskapligt)
    Abstract [en]

    With the help of the saw simulation program Saw2010, and the Swedish stem bank, a simulated sawing of 1288 logs has been performed, after which planks and boards have been quality-determined according to Nordic Wood (the Blue Book) and evaluated. After a large number of simulations on boards and planks of pine and spruce, it can be stated that value optimization gives a higher value yield than volume optimization in all three realistic price situations tested. The total value varies between price ranges and types of wood but is stably better on all runs with value optimization compared with volume optimization. The result is described as the total value increase in percent for all products in each run. A total of three runs were made in pine and three in spruce with respectively low, intermediate, and high prize level. The highest increase in value for edging with value optimization, compared with volume optimization, is found in both pine and spruce in the lowest price level, 5.1% and 5.0%, respectively. At the intermediate price level, the increase in value is 4.2% for pine and 3.3% for spruce. The highest price level gave a value increase of 3.0% for pine and 1.8% for spruce in value optimization compared with volume optimization. Simulations with changed quality parameters were also performed. One simulation was performed with a smaller permitted wane and one with larger permitted knots on the flat face compared to Nordic Wood. Also, these simulations showed clearly increased value in value optimization compared with volume optimization.

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  • 32.
    Garemark, Jonas
    et al.
    KTH Royal Institute of Technology, Sweden.
    Ram, Farsa
    KTH Royal Institute of Technology, Sweden.
    Liu, Lianlian
    KTH Royal Institute of Technology, Sweden.
    Sapouna, Ioanna
    KTH Royal Institute of Technology, Sweden.
    Cortes Ruiz, Maria
    KTH Royal Institute of Technology, Sweden.
    Larsson, Per Tomas
    RISE Research Institutes of Sweden. KTH Royal Institute of Technology, Sweden.
    Li, Yuanyuan
    KTH Royal Institute of Technology, Sweden.
    Advancing Hydrovoltaic Energy Harvesting from Wood through Cell Wall Nanoengineering2023Ingår i: Advanced Functional Materials, ISSN 1616-301X, E-ISSN 1616-3028, Vol. 33, nr 4, artikel-id 2208933Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Converting omnipresent environmental energy through the assistance of spontaneous water evaporation is an emerging technology for sustainable energy systems. Developing bio-based hydrovoltaic materials further pushes the sustainability, where wood is a prospect due to its native hydrophilic and anisotropic structure. However, current wood-based water evaporation-assisted power generators are facing the challenge of low power density. Here, an efficient hydrovoltaic wood power generator is reported based on wood cell wall nanoengineering. A highly porous wood with cellulosic network filling the lumen is fabricated through a green, one-step treatment using sodium hydroxide to maximize the wood surface area, introduce chemical functionality, and enhance the cell wall permeability of water. An open-circuit potential of ≈140 mV in deionized water is realized, over ten times higher than native wood. Further tuning the pH difference between wood and water, due to an ion concentration gradient, a potential up to 1 V and a remarkable power output of 1.35 µW cm−2 is achieved. The findings in this study provide a new strategy for efficient wood power generators. © 2022 The Authors. 

  • 33.
    Grahn, Thomas
    et al.
    RISE Research Institutes of Sweden, Samhällsbyggnad, Bygg och fastighet.
    Yassin, Zakiya
    RISE Research Institutes of Sweden, Samhällsbyggnad, Bygg och fastighet.
    Detection of wood species and defects with NIR2022Rapport (Övrigt vetenskapligt)
    Abstract [en]

    In this project the possibility to determine different wood species and detect defects on wood cross-sections on logs with hyperspectral near-infrared camera was investigated. This project was a laboratory study where cross-sections of logs were scanned at the wood and fibre analysis laboratory at RISE with near-infrared instrument.Wood samples from different origins and species, with different defects were scanned with a hyperspectral near-infrared camera. Classification models were developed to characterise and classify the different logs.Spruce and pine samples were collected from different sawmills, a group of these samples contained fungal growth. The defects within the collected logs varied and some samples contained decay fungi such as sap- and heart rot as well as non-destructive blue stain. Classifications models to distinguish between different wood species were developed, as well classification models to differentiate between healthy wood and the fungal attack were also developed.

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  • 34. Gräns, D.
    et al.
    Hannrup, B.
    Isik, F.
    Lundqvist, Sven-Olof
    RISE., STFI-Packforsk.
    McKeand, S.
    Genetic variation and relationships to growth traits for microfibril angle, wood density and modulus of elasticity in a Picea abies clonal trial in southern Sweden2009Ingår i: Scandinavian Journal of Forest Research, ISSN 0282-7581, E-ISSN 1651-1891, Vol. 24, nr 6, s. 494-503Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Genetic variation in wood density, microfibril angle (MFA), wood stiffness (MOE), height, diameter and volume was investigated in a 26-year-old Norway spruce [(Picea abies (L.) Karst.] clonal trial in southern Sweden. Wood quality measurements were performed on 10 mm increment cores using SilviScan. For MFA, mean values of annual rings showed the highest value (30°) at ring 2 counting from the pith, followed by a steep decrease and a gradual stabilization around ring 12 at approximately 14°. MOE showed a monotonic increase from 5 GPa to 14 GPa when moving from pith to bark. High broad-sense heritability values were found for wood density (0.48), MFA (0.41) and MOE (0.50). All growth traits displayed heritability values of similar magnitudes as reported in earlier studies. The generally high age-age correlations between different sections of the wood cores suggested that early selection for wood quality traits would be successful. Owing to unfavorable genetic correlations between volume and MOE, the correlated response indicated that selection for volume only at age 10 would result in a 0.27% decrease in weighted MOE at age 26 for every 1% increase in volume.

  • 35.
    Guo, Fei
    et al.
    Fujian Agriculture and Forestry University, China.
    Zhang, Xuexia
    Fujian Agriculture and Forestry University, China.
    Yang, Rrilong
    Fujian Agriculture and Forestry University, China.
    Salmen, Lennart
    RISE Research Institutes of Sweden.
    Yu, Yan
    Fujian Agriculture and Forestry University, China.
    Hygroscopicity, degradation and thermal stability of isolated bamboo fibers and parenchyma cells upon moderate heat treatment2021Ingår i: Cellulose, ISSN 0969-0239, E-ISSN 1572-882X, Vol. 28, nr 13, s. 8867-8876Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Parenchyma cells and fibers are the two dominant types of cells in the bamboo culm. Their mechanical and biological functions in bamboo differ substantially, derived from their cell wall structures and chemical compositions. The objective of this work was to comparatively study the hygroscopicity and the thermal degradation of bamboo fibers and parenchyma cells in order to better understand how to optimize heat treatment of bamboo. FTIR spectroscopy showed that parenchyma cells had a higher hemicellulose content and higher S/G lignin ratio than bamboo fibers based on the spectral changes at 1602 cm−1 with respect to 1505 cm−1. Upon heat treatment, spectral changes related to esterification reactions and loss of hydroxyl groups were observed. The heat treatment reduced hygroscopicity of parenchyma cells more than for bamboo fibers due to their lower thermal stability attributed to the higher hemicellulose content and less compact cell wall structure. Although heat treatment at 180 °C could improve the thermal stability of bamboo, mild heat treatments at 140 °C and 160 °C were found to be adequate to facilitate the degradation of bamboo. © 2021, The Author(s)

  • 36.
    Guo, Juan
    et al.
    Chinese Academy of Forestry, China.
    Song, Kunlin
    Chinese Academy of Forestry, China.
    Salmen, Lennart
    RISE., Innventia. KTH Royal Institute of Technology, Sweden.
    Yin, Yafang
    Chinese Academy of Forestry, China; KTH Royal Institute of Technology, Sweden.
    Changes of wood cell walls in response to hygro-mechanical steam treatment2015Ingår i: Carbohydrate Polymers, ISSN 0144-8617, E-ISSN 1879-1344, Vol. 115, s. 207-214Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The effects of compression combined with steam treatment (CS-treatment), i.e. a hygro-mechanical steam treatment on Spruce wood were studied on a cell-structure level to understand the chemical and physical changes of the secondary cell wall occurring under such conditions. Specially, imaging FT-IR microscopy, nanoindentation and dynamic vapour absorption were used to track changes in the chemical structure, in micromechanical and hygroscopic properties. It was shown that CS-treatment resulted in different changes in morphological, chemical and physical properties of the cell wall, in comparison with those under pure steam treatment. After CS-treatment, the cellular structure displayed significant deformations, and the biopolymer components, e.g. hemicellulose and lignin, were degraded, resulting in decreased hygroscopicity and increased mechanical properties of the wood compared to both untreated and steam treated wood. Moreover, CS-treatment resulted in a higher degree of degradation especially in earlywood compared to a more uniform behaviour of wood treated only by steam.

  • 37.
    Hayatgheibi, Haleh
    et al.
    SLU Swedish University of Agricultural Sciences, Sweden.
    Forsberg, Nils Erik Gustaf
    SLU Swedish University of Agricultural Sciences, Sweden.
    Lundqvist, Sven-Olof
    RISE - Research Institutes of Sweden, Bioekonomi. IIC Industrinc Internationaliserings Center, Sweden.
    Mörling, Tommy
    SLU Swedish University of Agricultural Sciences, Sweden.
    Mellerowicz, Ewa J
    SLU Swedish University of Agricultural Sciences, Sweden.
    Karlsson, Bo
    Ekebo Skogsförvaltning, Sweden.
    Wu, Harry X
    SLU Swedish University of Agricultural Sciences, Sweden.
    Garci­a-Gil, M. Rosario
    SLU Swedish University of Agricultural Sciences, Sweden.
    Genetic control of transition from juvenile to mature wood with respect to microfibril angle in Norway spruce (Picea abies) and lodgepole pine (Pinus contorta)2018Ingår i: Canadian Journal of Forest Research, ISSN 0045-5067, E-ISSN 1208-6037, Vol. 48, nr 11, s. 1358-1365Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Genetic control of microfibril angle (MFA) transition from juvenile wood to mature wood was evaluated in Norway spruce (Picea abies (L.) Karst) and lodgepole pine (Pinus contorta Douglas ex Loudon). Increment cores were collected at breast height (1.3 m) from 5664 trees in two 21-year-old Norway spruce progeny trials in southern Sweden and from 823 trees in two lodgepole pine progeny trials, aged 34–35 years, in northern Sweden. Radial variations in MFA from pith to bark were measured for each core using SilviScan. To estimate MFA transition from juvenile wood to mature wood, a threshold level of MFA 20° was considered, and six different regression functions were fitted to the MFA profile of each tree after exclusion of outliers, following three steps. The narrow-sense heritability estimates (h2) obtained for MFA transition were highest based on the slope function, ranging from 0.21 to 0.23 for Norway spruce and from 0.34 to 0.53 for lodgepole pine, while h2 were mostly non-significant based on the logistic function, under all exclusion methods. Results of this study indicate that it is possible to select for an earlier MFA transition from juvenile wood to mature wood in Norway spruce and lodgepole pine selective breeding programs, as the genetic gains (∆G) obtained in direct selection of this trait were very high in both species.

  • 38.
    Hägg, Linus
    RISE Research Institutes of Sweden, Samhällsbyggnad, Bygg och fastighet.
    Matchning av stockar till rätt träd2020Rapport (Övrigt vetenskapligt)
    Abstract [sv]

    I projektet har möjligheten att på individnivå sammankoppla timmersorteringsdata med skördardata undersökts. Syftet med en sådan undersökning är att åstadkomma digitalspårbarhet från skog till såg. En kopplad datamängd har insamlats och använts för att utforma algoritmer för automatisk koppling av timmersorteringsdata och skördardata påindividnivå. Förutsatt att stockar kan sättas samman till stammar med hjälp av timmersorteringsdata gäller att omkring 16% av alla stammar med minst 3 sågstockar medhög säkerhet kan kopplas samman i de två datamängderna. En algoritm för sammansättningav stockar till stammar med hjälp av timmersorteringsdata har också utvecklats men denna bedöms i nuvarande form ej nå tillräcklig prestanda. Potentialen att höja prestandan är dock till stor del ännu outforskad.

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  • 39.
    Janga, Kando K.
    et al.
    NTNU Norwegian University of Science and Technology, Norway.
    Öyaas, Karin
    RISE., Innventia, PFI – Paper and Fiber Research Institute.
    Hertzberg, Terje
    NTNU Norwegian University of Science and Technology, Norway.
    Moe, Stærker T.
    NTNU Norwegian University of Science and Technology, Norway.
    Application of a pseudo-kinetic generalized severity model to the concentrated sulfuric acid hydrolysis of pinewood and aspenwood2012Ingår i: BioResources, ISSN 1930-2126, E-ISSN 1930-2126, Vol. 7, s. 2728-2741Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The yield of monosaccharides after two-stage concentrated sulfuric acid hydrolysis of softwood (Scots pine) and hardwood (trembling aspen) was modeled using a generalized severity parameter with a time-independent rate constant. The severity parameter, which combines the major operating variables acid concentration, temperature, and reaction time in the decrystallization stage into a single reaction ordinate, was successfully used to describe monosaccharide yields after a standardized hydrolysis stage. Conversion of cellulose to glucose demanded a higher severity to reach maximum glucose yields than the conversion of hemicelluloses to their respective monosaccharides, and the conversion of pine demanded a higher severity to obtain maximum monosaccharide yields as compared to aspen. The results indicate that the generalized severity parameter can be a useful tool for the prediction of sugar yields in a two-stage concentrated sulfuric acid hydrolysis process.

  • 40.
    Jansson, M.B.
    et al.
    RISE., Innventia.
    Aldaeus, F.
    RISE., Innventia.
    Reimann, A.
    RISE., Innventia.
    Ljungquist, P.
    RISE., Innventia.
    Schweinebarth, H.
    RISE., Innventia.
    Boklund, M.
    Extraction of bioactive chemicals in spruce wood residues2011Konferensbidrag (Refereegranskat)
  • 41. Johnson, O.
    et al.
    Lindberg, Siv M
    RISE., STFI-Packforsk.
    Roos, A.
    Hugosson, M.
    Lindström, Mikael
    RISE., STFI-Packforsk.
    Consumer perceptions and preferences on solid wood, wood-based panels, and composites: A repertory grid study2008Ingår i: Wood and Fiber Science, ISSN 0735-6161, Vol. 40, nr 4, s. 663-678Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Knowledge about consumer perception and preferences on solid wood, wood-based panels, and wood-based composites is important for product development and marketing. The aim of this study was to identify attributes and associations that people use to describe different types of wood materials and to explore how they relate to preferences. The study involved nine samples that were evaluated with the Kelly’s repertory grid technique and content analysis. Based on respondents’ answers, 19 core categories reflecting sample attributes were extracted. General preferences for each sample were also recorded. Principal component analysis generated two factors describing 1) naturalness, wood-likeness, softness, unprocessed origin, living, pleasant, and high value; and 2) solid and homogeneous impression. A third, preliminary factor included categories describing irregular pattern, sleekness, and smoothness. The wood samples were most liked, whereas composites and panels were not appreciated. Preferred core categories were naturalness, wood-likeness, smoothness, living impression, and value. The least liked core categories were processed, hard, and high weight. The implications of the results for product development and marketing are discussed. © 2008 by the Society of Wood Science and Technology.

  • 42.
    Jones, Grace
    et al.
    Ashtown Research Centre, Ireland.
    Ulan, Maria
    RISE Research Institutes of Sweden, Digitala system, Mobilitet och system.
    Liziniewicz, Mateusz
    Skogforsk The Forest Research Institute of Sweden, Sweden.
    Lindeberg, Johan
    Linnaeus university, Sweden.
    Adamopoulos, Stergios
    SLU Swedish University of Agricultural Sciences, Sweden.
    Relating estimates of wood properties of birch to stem form, age and species2024Ingår i: Journal of Forestry Research, ISSN 1007-662X, E-ISSN 1993-0607, Vol. 35, nr 1, artikel-id 14Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Birch has long suffered from a lack of active forest management, leading many researchers to use material without a detailed management history. Data collected from three birch (Betula pendula Roth, B. pubescens Ehrh.) sites in southern Sweden were analyzed using regression analysis to detect any trends or differences in wood properties that could be explained by stand history, tree age and stem form. All sites were genetics trials established in the same way. Estimates of acoustic velocity (AV) from non-destructive testing (NDT) and predicted AV had a higher correlation if data was pooled across sites and other stem form factors were considered. A subsample of stems had radial profiles of X-ray wood density and ring width by year created, and wood density was related to ring number from the pith and ring width. It seemed likely that wood density was negatively related to ring width for both birch species. Linear models had slight improvements if site and species were included, but only the youngest site with trees at age 15 had both birch species. This paper indicated that NDT values need to be considered separately, and any predictive models will likely be improved if they are specific to the site and birch species measured. © 2023, The Author(s).

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  • 43.
    Kaschuk, Joice
    et al.
    Aalto University, Finland.
    Al Haj, Yanan
    Aalto University, Finland.
    Rojas, Orlando
    Aalto University, Finland; University of British Columbia, Canada.
    Miettunen, Kati
    University of Turku, Finland.
    Abitbol, Tiffany
    RISE Research Institutes of Sweden, Bioekonomi och hälsa, Material- och ytdesign.
    Vapaavuori, Jaana
    Aalto University, Finland.
    Plant-Based Structures as an Opportunity to Engineer Optical Functions in Next-Generation Light Management2022Ingår i: Advanced Materials, ISSN 0935-9648, E-ISSN 1521-4095, Vol. 34, nr 6, artikel-id 2104473Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This review addresses the reconstruction of structural plant components (cellulose, lignin, and hemicelluloses) into materials displaying advanced optical properties. The strategies to isolate the main building blocks are discussed, and the effects of fibrillation, fibril alignment, densification, self-assembly, surface-patterning, and compositing are presented considering their role in engineering optical performance. Then, key elements that enable lignocellulosic to be translated into materials that present optical functionality, such as transparency, haze, reflectance, UV-blocking, luminescence, and structural colors, are described. Mapping the optical landscape that is accessible from lignocellulosics is shown as an essential step toward their utilization in smart devices. Advanced materials built from sustainable resources, including those obtained from industrial or agricultural side streams, demonstrate enormous promise in optoelectronics due to their potentially lower cost, while meeting or even exceeding current demands in performance. The requirements are summarized for the production and application of plant-based optically functional materials in different smart material applications and the review is concluded with a perspective about this active field of knowledge. © 2021 The Authors.

  • 44.
    Knapic, Sofia
    et al.
    Universidade de Lisboa, Portugal.
    Grahn, Thomas
    RISE - Research Institutes of Sweden (2017-2019), Bioekonomi, Papperstillverkning och förpackningar.
    Lundqvist, Sven-Olof
    RISE - Research Institutes of Sweden (2017-2019), Bioekonomi.
    Pereira, Helena
    Universidade de Lisboa, Portugal.
    Juvenile wood characterization of Eucalyptus botryoides and E. maculata by using SilviScan2018Ingår i: BioResources, ISSN 1930-2126, E-ISSN 1930-2126, Vol. 13, nr 2, s. 2342-2355Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The wood properties of 6-year-old Eucalyptus botryoides and Eucalyptus maculata point towards a possible aptitude for solid-wood end uses. Samples from E. botryoides and E. maculata were characterized regarding within-tree variation in wood density, radial and tangential fibre width, fibre wall thickness, fibre coarseness, microfibril angle, and stiffness based on SilviScan measurements taken radially from the pith outwards at varying stem height levels. The mean values of the studied wood properties for E. botryoides and E. maculata were, respectively: density 507 kg m-3 and 695 kg m-3, radial fibre width 17.4 Όm and 17.2 Όm, tangential fibre width 16.7 Όm and 16.9 Όm, fibre wall thickness 1.8 Όm and 2.5 Όm, fibre coarseness 161.2 Όgm-1 and 212.9 Όgm-1, microfibril angle 15.5° and 14.7°, and stiffness 9.6 GPa and 12.1 GPa. The variation in wood stiffness was explained to a large extent by microfibril angle and wood density variations. The results of the scans, along with the wood variability, indicated that both species should be considered for solid wood products or pulp production.

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  • 45. Kostiainen, K.
    et al.
    Kaakinen, S.
    Saranpää, P.
    Sigurdsson, B. D.
    Lundqvist, Sven-Olof
    RISE., STFI-Packforsk.
    Linder, S.
    Vapaavuori, E.
    Stem wood properties of mature Norway spruce after 3 years of continuous exposure to elevated [CO2] and temperature2009Ingår i: Global Change Biology, ISSN 1354-1013, E-ISSN 1365-2486, Vol. 15, nr 2, s. 368-379Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The objective of the study was to investigate the interactive effects of elevated atmospheric carbon dioxide concentration, [CO2], and temperature on the wood properties of mature field-grown Norway spruce (Picea abies (L.) Karst.) trees. Material for the study was obtained from an experiment in Flakaliden, northern Sweden, where trees were grown for 3 years in whole-tree chambers at ambient (365 ÎŒmol mol-1) or elevated [CO2] (700 ÎŒmol mol-1) and ambient or elevated air temperature (ambient +5.6°C in winter and ambient +2.8°C in summer). Elevated temperature affected both wood chemical composition and structure, but had no effect on stem radial growth. Elevated temperature decreased the concentrations of acetone-soluble extractives and soluble sugars, while mean and earlywood (EW) cell wall thickness and wood density were increased. Elevated [CO2] had no effect on stem wood chemistry or radial growth. In wood structure, elevated [CO2] decreased EW cell wall thickness and increased tracheid radial diameter in latewood (LW). Some significant interactions between elevated [CO2] and temperature were found in the anatomical and physical properties of stem wood (e.g. microfibril angle, and LW cell wall thickness and density). Our results show that the wood material properties of mature Norway spruce were altered under exposure to elevated [CO2] and temperature, although stem radial growth was not affected by the treatments. © 2008 The Authors Journal compilation © 2008 Blackwell Publishing.

  • 46.
    Kostiainen, Katri
    et al.
    Finnish Forest Research Institute, Finland.
    Saranpää, Pekka T.
    Finnish Forest Research Institute, Finland.
    Lundqvist, Sven Olof
    RISE., Innventia.
    Kubiske, Mark E.
    Forestry Sciences Laboratory, USA.
    Vapaavuori, Elina M.
    Finnish Forest Research Institute, Finland.
    Wood properties of Populus and Betula in long-term exposure to elevated CO2 and O32014Ingår i: Plant, Cell and Environment, ISSN 0140-7791, E-ISSN 1365-3040, Vol. 37, nr 6, s. 1452-1463Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We studied the interactive effects of elevated concentrations of CO2 and O3 on radial growth and wood properties of four trembling aspen (Populus tremuloidesMichx.) clones and paper birch (Betula papyriferaMarsh.) saplings. The material for the study was collected from the Aspen FACE (free-air CO2 enrichment) experiment in Rhinelander (WI, USA). Trees had been exposed to four treatments [control, elevated CO2 (560ppm), elevated O3 (1.5 times ambient) and combined CO2+O3] during growing seasons 1998-2008. Most treatment responses were observed in the early phase of experiment. Our results show that the CO2- and O3-exposed aspen trees displayed a differential balance between efficiency and safety of water transport. Under elevated CO2, radial growth was enhanced and the trees had fewer but hydraulically more efficient larger diameter vessels. In contrast, elevated O3 decreased radial growth and the diameters of vessels and fibres. Clone-specific decrease in wood density and cell wall thickness was observed under elevated CO2. In birch, the treatments had no major impacts on wood anatomy or wood density. Our study indicates that short-term impact studies conducted with young seedlings may not give a realistic view of long-term ecosystem responses.

  • 47.
    Kymäläinen, Maija
    et al.
    Aalto University, Finland.
    Hautamäki, Saara
    Aalto University, Finland.
    Lillqvist, Kristiina
    KTH Royal Institute of Technology, Sweden.
    Segerholm, Kristoffer
    RISE - Research Institutes of Sweden, Bioekonomi. KTH Royal Institute of Technology, Sweden.
    Rautkari, Lauri
    Aalto University, Finland.
    Surface modification of solid wood by charring2017Ingår i: Journal of Materials Science, ISSN 0022-2461, E-ISSN 1573-4803, Vol. 52, nr 10, s. 6111-6119Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Most wooden structures for outdoor applications require repetitive maintenance operations to protect the surfaces from adverse effects of weathering. One-sided surface modification of boards with a relatively fast charring process has the potential to increase the durability and service life of wooden claddings. To assess some weathering-related effects on surface charred wood, spruce and pine sapwood were subjected to a series of long charring processes (30–120 min) at a moderate temperature of 250 °C and to a short one (30 s) at a high temperature of 400 °C. The wettability and contact angles of treated samples were investigated, and the heat transfer was measured along with the micromorphological changes taking place in the material. The result revealed an increased moisture resistance of charred spruce sapwood and an increased water uptake of pine sapwood. The contact angles of both wood species improved compared to references. Heat conduction measurement revealed that only a thin section of the wood was thermally modified. Some micromorphological changes were recorded, especially on the inside walls of the lumina. The results show that spruce sapwood has an improved resistance towards moisture-induced weathering, but more studies are needed to unlock the potential of surface charred wood.

  • 48.
    Larsson, Per Tomas
    et al.
    RISE., Innventia. KTH Royal Institute of Technology, Sweden.
    Svensson, Anna
    KTH Royal Institute of Technology, Sweden.
    Wågberg, Lars Göran
    KTH Royal Institute of Technology, Sweden.
    A new, robust method for measuring average fibre wall pore sizes in cellulose I rich plant fibre walls2013Ingår i: Cellulose, ISSN 0969-0239, E-ISSN 1572-882X, Vol. 20, nr 2, s. 623-631Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A new, robust method for measuring the average pore size of water-swollen, cellulose I rich fibres is presented. This method is based on the results of solid-state NMR, which measures the specific surface area (area/solids mass) of water-swollen samples, and of the fibre saturation point (FSP) method, which measures the pore volume (water mass/solids mass) of water-swollen samples. These results are suitable to combine since they are both recorded on water-swollen fibres in excess water, and neither requires the assumption of any particular pore geometry. The new method was used for three model samples and reasonable average pore size measurements were obtained for all of them. The structural characterization of water-swollen samples was compared with the dry structure of fibres as revealed using BET nitrogen gas adsorption after a liquid exchange procedure and careful drying. It was concluded that the structure of the water-swollen fibres sets an upper limit on what is obtainable in the dry state.

  • 49.
    Lemke, Ulf
    et al.
    RISE Research Institutes of Sweden, Samhällsbyggnad, Bygg och fastighet.
    Johansson, Marie
    RISE Research Institutes of Sweden, Samhällsbyggnad, Bygg och fastighet.
    Ziethén, Rune
    RISE Research Institutes of Sweden, Samhällsbyggnad, Bygg och fastighet.
    Briggert, Andreas
    RISE Research Institutes of Sweden, Samhällsbyggnad, Bygg och fastighet. Jönköping University, Sweden.
    NEW CRITERIA FOR VISUAL STRENGTH GRADING OF SAWN TIMBER FROM BIRCH GROWN IN SWEDEN2023Konferensbidrag (Refereegranskat)
    Abstract [en]

    Today there is no standard for strength grading and CE-marking sawn timber of Birch grown in Sweden, which makes it impossible to use this material as structural timber. Internationally, there are standards for visual grading of hardwood in several European countries. However, these standards may not be used to classify Birch timber grown in Sweden without having been tested and verified to meet the standard's requirements. In a project (BizWOOD) run by RISE, 600 pieces of sawn birch wood from Sweden is visually graded and strength tested. The project aims to result in grading rules for birch, either by using international standards or where international standards will be used as references for the identification of defects that will be included in the grading model. This paper summarizes parts of the BizWOOD project and includes 1) description of sampling and timber origin, 2) visual grading according to international standards, 3) strength testing of the material, 4) evaluation of mechanical characteristics, 5) evaluation of grading techniques.

  • 50. Lindblad, M. S.
    et al.
    Dahlman, Olof
    RISE., STFI-Packforsk.
    Sjöberg, J.
    Albertsson, A. -C
    Modified galactoglucomannans from forestry waste-water for films and hydrogels2009Ingår i: American Chemical Society Symposium Series (ACS), ISSN 0097-6156, E-ISSN 1947-5918, Vol. 1017, s. 185-198Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Hemicelluloses are among the most abundant natural polymers in the world and are consequently a potential source for sustainable materials, that has so far been underexploited. Galactoglucomannans are the principal hemicelluloses in softwoods and can be found in, for example, industrial wood processing waste-water. Currently, we are investigating the fractionation and purification of O-acetylgalactoglucomannans from newsprint and fiberboard mill waste-waters, as well as the preparation of new barrier films with low oxygen permeation and hydrogel materials from the fractions obtained. Self-supporting films have been formed by solution-casting. Interesting oxygen barrier and mechanical strength properties were achieved for films obtained from a physical blend of O-acetyl-galactoglucomannan and either alginate or carboxymethylcellulose. To create oxygen barrier films with high resistance towards moisture, benzylated derivatives of O-acetyl-galactoglucomannan were made. A hydrogel is a polymeric material that swells in water but does not dissolve, valuable for applications including drug delivery. In order to obtain the right properties, we performed tailored cross-linking to create a flexible network structure. The chemical modification procedure involves a methacrylation reaction carried out under mild conditions. Herein we review past work and present some new data on fractionation and purification of galactoglucomannans. © 2009 American Chemical Society.

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