Publikasjoner
NIBIOs ansatte publiserer flere hundre vitenskapelige artikler og forskningsrapporter hvert år. Her finner du referanser og lenker til publikasjoner og andre forsknings- og formidlingsaktiviteter. Samlingen oppdateres løpende med både nytt og historisk materiale. For mer informasjon om NIBIOs publikasjoner, besøk NIBIOs bibliotek.
2025
Forfattere
Wiesław Olek Waldemar Perdoch Andreas Treu Jerzy Majka Łukasz Czajkowski Bartłomiej Mazela Jerzy WeresSammendrag
The interaction of cellulose paper with water is a major hindrance to its broader application. This study, which introduces a novel approach to understand water vapor difusion in both untreated and treated paper, aims to identify the difusion coefcient, a crucial property in improving the hydrophobicity of paper. The treatment process utilized an aqueous solution of starch or starch modifed with methyltrimethoxysilane (MTMS). While the initial sorption method is frequently used to determine the difusion coefcient, this study found that it could lead to signifcant errors due to the non-Fickian behavior exhibited by lignocellulosic materials. This behavior causes that the hygroscopic equilibrium is not instantly obtained by surface of paper. It also induces slowing down moisture difusion in its fnal stage due to molecular relaxation. For the frst time, the modifed convective boundary condition was introduced into the moisture difusion model in paper materials. The results from vapor sorption experiments demonstrated this non-Fickian behavior, particularly at high values of air relative humidity. The study also revealed that the commonly applied frst kind boundary condition is not applicable, even for thin paper samples, inhibiting the use of the initial sorption method for determining the difusion coefcient. While the treatment with starch and MTMS signifcantly improved the hydrophobic properties of paper, it didn’t alter substantially its hygroscopic properties, potentially due to not blocking active sorption sites of cellulose fbers. This research underscores the need for further investigation into the chemical modifcation of cellulose fbers to improve the hydrophobicity of paper.
Forfattere
Samuel L. Zelinka Samuel V. Glass Natalia Farkas Emil E. Thybring Michael Altgen Lauri Rautkari Simon Curling Jinzhen Cao Yujiao Wang Tina Künniger Gustav Nyström Christopher Hubert Dreimol Ingo Burgert Mark G. Roper Darren P. Broom Matthew Schwarzkopf Arief Yudhanto Mohammad Subah Gilles Lubineau Maria Fredriksson Wiesław Olek Jerzy Majka Nanna Bjerregaard Pedersen Daniel J. Burnett Armando R. Garcia Frieder Dreisbach Louis Waguespack Jennifer Schott Luis G. Esteban Alberto García‑Iruela Thibaut Colinart Romain Rémond Brahim Mazian Patrick Perré Lukas EmmerichSammendrag
Automated sorption balances are widely used for characterizing the interaction of water vapor with hygroscopic materials. This paper is part of an interlaboratory study investigating the stability and performance of automated sorption balances. A previous paper in this study investigated the mass, temperature, and relative humidity (RH) stability of automated sorption balances by looking at the mass change of a non-hygroscopic sample over time. In this study, we examine the mass stability of wood samples held at constant RH for seven to ten days after a step change. The reason for the long hold times was to collect data to “operational equilibrium” where the change in mass is on the order of the inherent operational stability of the instrument. A total of 80 datasets were acquired from 21 laboratories covering absorption with final RH levels ranging from 10 to 95%. During these long hold times, several unusual behaviors were observed in the mass-vs-time curves. Deviations from expected sorption behavior were examined by fitting the data to an empirical sorption kinetics model and calculating the root mean square error (RMSE) between the observed and smoothed behavior. Samples that had a large RMSE relative to the median RMSE of the other datasets often had one of several types of errors: abrupt disturbances, diurnal oscillations, or long-term mass decline during an absorption step. In many cases, mass fluctuations were correlated with changes in the water reservoir temperature of the automated sorption balance. We discuss potential errors in sorption measurements on hygroscopic materials and suggest an acceptable level of RMSE for sorption data.
Sammendrag
The spatio-temporal heterogeneity of in-ground wood decay risk is important to service life planning of timber components. To achieve a desired service life in years related to a component’s expected performance, means accurately matching the durability characteristics of the wooden material to the exposure location. In this context, the integration of service life planning of timber with remote-sensing data services shows promise. Soil moisture and temperature data from the ERA5-Land repository were extracted for Europe over a 9 × 9 km point grid, between January 1993 and December 2022. The data were then appropriately scaled and used as input to an in-ground wood decay dose–response model. The resulting hazard map plotted dose to indicate annual in-ground wood decay risk, as a function of exposure to daily soil temperature and soil moisture conditions. Regions with low decay risk reflected temperature-limiting, oxygen-limiting or moisture-limiting soil conditions, all of which are unsuitable for fungal decay processes. Temporal investigations of the processed data revealed fungal growth windows influenced by seasonality. By better understanding the effects and occurrences of these unfavourable fungal decay conditions, the underlying dose–response model can be refined to deliver more accurate predictions of service life for in-ground wooden components.
Sammendrag
Post-Consumer Wood (PCW) is a valuable resource that could substitute virgin wood in many applications. However, its integration into the wood processing chain requires detailed information on composition, content of contaminants, size, and shape. Here, PCW collected over eight months from three sorting facilities in southeastern Norway was analyzed for suitability in recycling. Shredded PCW from 24 samples was manually sorted based on material origin, analyzed for heavy metal concentrations, and the particle geometry was measured with an automated laser scanner. Based on the results, 39–67 % of the mixed PCW was made up by clean wood particles suitable for recycling. Wood-based panels within the PCW were not only a source of contaminants (adhesives, coatings) but also decreased the length-to-width ratio of the resulting particles and chips. The median heavy metal concentrations did not exceed the limit values issued by the European Panel Federation. However, individual samples and the fine fraction (< 8 mm) exceeded these limit values. Manual pre-sorting before shredding into chips increased the share of clean wood particles, prevented elevated fiberboard contents and significantly reduced heavy metal concentrations.
Forfattere
Morten Rese Gijs van Erven Romy J. Veersma Gry Alfredsen Vincent Eijsink Mirjam A. Kabel Tina Rise TuvengSammendrag
Wood-degrading brown-rot fungi primarily target carbohydrates, leaving the lignin modified and potentially valuable for valorization. Here, we report a comprehensive comparison of how Gloeophyllum trabeum in vitro degrades hardwood and softwood, which have fundamentally different lignin structures. By harnessing the latest advancements in analytical methodologies, we show that G. trabeum removes more lignin from wood (up to 36%) than previously reported. The brown-rot decayed lignin appeared substantially Cα-oxidized, O-demethylated, with a reduction in interunit linkages, leading to formation of substructures indicative of Cα-Cβ, β-O, and O-4 cleavage. Our work shows that the G. trabeum conversion of hardwood and softwood lignin results in similar modifications, despite the structural differences. Furthermore, lignin modification by G. trabeum enhances the antioxidant capacity of the lignin and generates an extractable lower molecular weight fraction. These findings improve our understanding of lignin conversion by brown-rot fungi and highlight their biotechnological potential for the development of lignin-based products.
Forfattere
Paul Eric Aspholm David Kniha Amelie Bringemeier Philipp Michel Monica Fongen Hans Nyeggen Jarle W. BjerkeSammendrag
Det er ikke registrert sammendrag
Forfattere
Geir Wæhler Gustavsen Philip Bester van Niekerk Jonas Niklewski Christian Brischke Gry AlfredsenSammendrag
With increased focus on sustainable building materials and the growing popularity of uncoated wooden cladding, understanding consumer acceptance of aesthetic changes becomes crucial for sustainable architectural choices. This study investigated consumer acceptance of uncoated wooden cladding in Norway, Sweden, and Germany, focusing on personality traits and perceptions. Using an online survey with 3112 participants, the study found that preference for uncoated wooden cladding was similar (around 20%) across the three countries, despite diferences in the prevalence of wooden cladding. A natural consequence of weathering of wood exposed outdoors is greying of the surface. The survey presented participants with images of uncoated wooden cladding with varying degrees of grey discolouration. Participants rated the acceptability of these claddings based on their preferences. Acceptance of this discolouration difered by country, Norwegians preferred intermediatecoloured panels, Swedes preferred darker panels, and Germans accepted all panels. Personality traits measured using the Big Five personality inventory and socioeconomic factors infuenced preferences. In Norway and Sweden, those accepting the discolouration of uncoated wooden cladding included introverts, highly conscientious individuals, young people, females, and those with tertiary education. Additionally, in Norway and Germany, openness to experience was linked to acceptance, while strong emotional control was signifcant only in Norway. This study underscores the complexity of consumer preferences for uncoated wooden cladding, demonstrating that personality traits, in conjunction with cultural and demographic variables, jointly infuence perception. The fndings ofer valuable insights for architects, builders, and policymakers seeking to advance sustainable construction practices while optimising consumer satisfaction in the housing sector.
Forfattere
Lone RossSammendrag
Det er ikke registrert sammendrag
Sammendrag
Det er ikke registrert sammendrag
2024
Sammendrag
Når sprengkulda fester grepet over store deler av landet, gjelder det å fyre i ovnen. Bjørkeved er populært, men hvorfor ikke velge gran? Nye tester viser at den brenner raskere, varmer godt og er lett å tenne - om den er tørr.