Published since January 1, 1947

Holzforschung

Cellulose – Hemicelluloses – Lignin – Wood Extractives

ISSN: 1437-434X

Editor-in-chief: Lennart Salmén

Editorial Board: Geoffrey Daniel, Holger Militz, Thomas Rosenau, Herbert Sixta, Tapani Vuorinen, Dimitris S. Argyropoulos, Yu Balakshin, J. R. Barnett, Ingo Burgert, Jose C. del Rio, Dmitry V. Evtuguin, Charles E. Frazier, Kazuhiko Fukushima, Wolfgang Gindl-Altmutter, W. G. Glasser, Bjarne Holmbom, Akira Isogai, John F. Kadla, Gerald Koch, Dominique Lachenal, Christiane Laine, Shawn D. Mansfield, J.J. Morrell, Peter Niemz, Antje Potthast, Arthur J. Ragauskas, John Ralph, Robert W. Rice, Uwe Schmitt, Tor P. Schultz, Jussi Sipilä, Toshiyuki Takano, Hans Theliander, Johannes Welling, Stefan Willför, Hiroshi Yoshihara

Impact Factor: 2.393

About this journal

Objective
Holzforschung (HF) is an international scholarly journal that publishes cutting-edge research on the biology, chemistry, physics and technology of wood and wood components. High quality papers about biotechnology and tree genetics are also welcome. Rated year after year as one of the top scientific journals in the category of Pulp and Paper (ISI Journal Citation Index), Holzforschung represents innovative, high quality basic and applied research. The German title reflects the journal's origins in a long scientific tradition, but all articles are published in English to stimulate and promote cooperation between experts all over the world. Ahead-of-print publishing ensures fastest possible knowledge transfer.

Topics

Biology, chemistry, physics and technology of wood and wood components
Biotechnology and tree genetics

Article formats
Original articles, Reviews, Short notes

> Information on submission process

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Your benefits:

Cutting-edge research
Interdisciplinary approach
High quality basic and applied research
Ahead-of-print online publications

History

Holzforschung was founded in 1947. At the start, German was the sole publishing language of Holzforschung. In 1955 it became also possible to publish in French and English, and in 1993 the journal switched to an English only publication. This change was necessary as after World War II German was no longer the leading language in the natural sciences. With the significant rise in international attention and distribution, Holzforschung paid tribute to the linguistic needs of the wood science community around the world.

Other publications in the field
Wood Composites. Materials Manufacturing and Engineering. J. Paulo Davim, Alfredo Aguilera (Eds.) De Gruyter. 2016.
Nordic Pulp & Paper Research Journal

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Volume 75 Issue 10

October 2021

Accessible October 4, 2021

Frontmatter

Page range: i-iii

Download PDF

Original articles

June 24, 2021

Ultrasound to estimate the physical-mechanical properties of tropical wood species grown in an agroforestry system

Adriano Reis Prazeres Mascarenhas, Rafael Rodolfo de Melo, Alexandre Santos Pimenta, Diego Martins Stangerlin, Fernando Luiz de Oliveira Corrêa, Marta Silvana Volpato Sccoti, Edgley Alves de Oliveira Paula

Page range: 879-891

Abstract

The great diversity of tropical wood species makes it difficult to obtain information about their technological properties. The present work employed ultrasound to estimate the physical and mechanical properties of four wood species: African mahogany ( Khaya senegalensis ), ‘freijó’ ( Cordia goeldiana ), ‘paricá’ ( Schizolobium amazonicum ), and teak ( Tectona grandis ). Nineteen-year-old adult trees were selected and harvested from an agroforestry system (AFS) located in the Brazilian Amazon. From the harvested trees, 1.5 m logs were sawn and test specimens were obtained for physical-mechanical assays. The ultrasound propagation speed ( V 0 ) and the dynamic modulus of elasticity ( E d ) were obtained from applying ultrasound longitudinally in wood samples. Values of V 0 decreased from the lightest wood (paricá) to the heaviest (African mahogany), and E d presented the opposite behavior. For the physical properties, the coefficient of determination ( R 2 ) ranged from 12 to 35% and the best linear regression models were fitted for the basic density, having V 0 and E d as independent variables. For the mechanical properties, the values of R 2 varied from 18 to 63% and higher correlations were found between parallel-to-grain compression strength and E d , and rigidity, static bending and E d . Ultrasound presented the potential to estimate the properties of tropical wood species from the ASF.

April 5, 2021

Natural durability and improved resistance of 20 Amazonian wood species after 30 years in ground contact

Fernando Nunes Gouveia, Marcelo Fontana da Silveira, Alencar Garlet

Page range: 892-899

Abstract

This study aimed to assess the natural durability of 20 Amazonian wood species preserved with chromated copper arsenate (CCA) after 30 years in ground contact in an experimental field test at National Forest of Tapajós, Pará state - Brazil. Heartwood samples with a cross-section of 5 × 5 cm and 50 cm of length were half-buried in soil and inspected every year for decay. The species were classified according to natural durability following the classification method proposed by Findlay (Findlay, W.P.K. (1985). The nature and durability of wood. In: Findlay, W.P.K. (Ed.), Preservation of timber in the tropics. Springer Science , Whitchurch, pp. 1–13). After 30 years in ground test, six species were classified as Perishable, seven as Non-durable, three as Durable and four as Very durable, namely: Trichilia lecointei , Lecythis pisonis , Pseudopiptadenia suaveolens , and Dipteryx odorata (Very durable), Protium tenuifolium , Dinizia excelsa , and Ormosia paraensis (Durable), Endopleura uchi , Goupia glabra , Pouteria egregia , Tachigali chrysophylla , Tachigali paraensis , Vatairea sericea , and Vochysia maxima (Non-durable) and Chrysophyllum lucentifolium , Couratari oblongifolia , Didymopanax morototoni , Lueheopsis duckeana , Sterculia excelsa , and Xylopia nitida (Perishable). CCA preservative treatment was effective to promote timber protection, even under harsh climatic conditions of the Amazon forest environment.

Open Access April 20, 2021

Cellular-level chemical changes in Japanese beech (Fagus crenata Blume) during artificial weathering

Toru Kanbayashi, Masahiro Matsunaga, Masahiko Kobayashi

Page range: 900-907

More Download PDF

Abstract

Since wood chemical components can be depolymerized and modified by weathering, a better understanding of the mechanisms governing these processes in needed to develop effective protection methods for wood surfaces. Unfortunately, very little has been reported about the micro-scale chemical changes in wood, particularly hardwood, during weathering. The purpose of the present work is to determine the degradation behavior of Japanese beech ( Fagus crenata Blume) under artificial weathering at the cellular-level. Herein, the structural and micro-distributional changes in wood components during weathering were investigated using micro-Raman spectral and chemical mapping analyses. The Raman spectra showed that weathering facilitated lignin degradation and modification. The degradation behavior of lignin differed depending on the type of wood tissue. The rate of lignin reduction followed a descending order: vessel element > axial parenchyma cell > wood fiber. Raman mapping determined that cellular-level lignin reduction on the surface layers differed for wood species. Although lignin degradation of cedar tracheids proceeded from both the surface and the cell lumen, the lignin in beech fibers degraded according to the depth.

April 5, 2021

Evaluation of water related properties of birch wood products modified with different molecular weight phenol-formaldehyde oligomers

Juris Grinins, Vladimirs Biziks, Janis Rizikovs, Ilze Irbe, Holger Militz

Page range: 908-916

Abstract

This study investigated the effect of phenol-formaldehyde (PF) resin treatment on the dimensional stability of birch solid wood and plywood. Therefore, three different low molecular weight PF resins with average molecular weights ( M w ) of 292, 528, and 884 g/mol were synthesized and used for silver birch ( Betula pendula ) solid wood (20 × 20 × 20 mm 3 ) and veneer (100 × 100 × 1.4 and 300 × 300 × 1.4 mm 3 ) impregnation to produce plywood. The weight percent gain (WPG) and bulking after curing of resin treated wood specimens were determined. The leaching was performed to evaluate the PF resin fixation stability. All tested resins at all concentrations were similarly fixed in wood blocks after the leaching (1.5–2.0% WPG loss). The dimensional stability of birch wood after treatment with all tested PF resins was significantly improved. The anti-swelling efficiency (ASE) of birch wood blocks treated with PF resins after seven water soaking-drying cycles was in the range of 39–53%, 46–65% and 49–65% using 10, 15 and 20% solution concentrations, respectively. Whereas, the ASE of plywood obtained from veneers treated with 10% of PF solution was improved by 6–20%. The equilibrium moisture content (EMC) and volumetric swelling (VS) of PF treated plywood at 98% of relative humidity (RH) decreased significantly. All PF resin treated plywood surfaces were more hydrophobic compared to untreated plywood.

April 20, 2021

Superhydrophobic wood surface fabricated by Cu₂O nano-particles and stearic acid: its acid/alkali and wear resistance

Ke Zhan, Sengwei Xia, Quanxiong Lu, Ruifeng Cheng, Haiqiu Jiang, Tengfei Yi, Jeffrey Morrell, Long Yang, Linkun Xie, Hong Lei, Guanben Du, Wei Gao

Page range: 917-931

Abstract

Reducing the hydrophilic nature of wood could enhance dimensional stability and improve life cycle performance. Masson pine and pecan wood were modified to create superhydrophobic, self-cleaning functions by spray-coating with Cu 2 O nano-particles (Cu 2 O NPs)/phenol formaldehyde (PF) resin mixed solution followed by immersion in a stearic acid ethanol solution. Two types of Cu 2 O NPs, derived from different concentrations of copper chloride (CuCl 2 ) were evaluated for their ability to improve hydrophobicity of wood surface. A special petal-shaped structure on the edge of Cu 2 O NPs was found on modified pecan wood, and water contact angles (WCA) of both kind of modified wood reached around 155° and sliding angles (SA) less than 10°. Meanwhile, low liquid permeability and excellent repellency to aqueous solutions with pH = 1 to 13 were achieved. The critical WCA around 150° was also maintained on modified wood surfaces after being immersed in strong acid (pH = 2) and strong alkali (pH = 12) solutions for 12 h. Furthermore, remarkable mechanical durability was obtained after harsh abrading test, which could be attributed to the high bond strength from cured PF resin adhesive. Such highly waterproof, acid/alkali resistant and hard-wearing superhydrophobic surface must have potential to be widely applied in wood products industry.

April 28, 2021

Dynamic strength properties and structural integrity of wood modified with cyclic N-methylol and N-methyl compounds

Lukas Emmerich, Christian Brischke, Susanne Bollmus, Holger Militz

Page range: 932-944

Abstract

Cyclic N -methylol compounds have been used for cell wall impregnation modifications of wood. Besides an improved decay resistance and dimensional stability, the modifications resulted in a decrease of wood’s dynamic strength properties. However, the mechanisms behind a significant loss in dynamic strength are not fully understood yet. In this study, wood blocks were treated with the N -methylol compounds 1,3-dimethylol-4,5-dihydroxyethyleneurea (DMDHEU) and methylated DMDHEU (mDMDHEU) and the N -methyl compound 1,3-dimethyl-4,5-dihydroxy-ethyleneurea (DMeDHEU). In order to study the factors that control the changes of wood performance under dynamic loads, single (impact bending strength, IBS) and multiple dynamic impact (resistance to impact milling, RIM) tests were applied. It became evident, that reductions in IBS and RIM increased with increasing solid content, formaldehyde content and catalyst concentration of the impregnation solutions, but were not affected by a cold-water leaching. Differences in structural integrity of wood modified with N -methylol and N -methyl compounds were more pronounced than those of IBS. Therefore, RIM appeared more sensitive to changes on cellular level, as a higher degree of co-condensation of the N -methylol compounds with cell wall polymers was expected in comparison with the N -methyl compound.

April 30, 2021

Indoor storage time affects the quality and quantity of volatile monoterpenes emitted from softwood timber

Riina Muilu-Mäkelä, Petri Kilpeläinen, Veikko Kitunen, Anni Harju, Martti Venäläinen, Tytti Sarjala

Page range: 945-956

Abstract

Wood as a construction material affects indoor environmental quality by moisture buffering, good acoustic properties and by the wood specific volatile organic compounds (VOC). The most abundant VOCs of soft wood are volatile monoterpenes (VM) giving the typical odor of wood. In the present study, long-term VM emissions of wood of two northern coniferous tree species, Scots pine and Norway spruce were observed regularly during one year in storage. Fresh and dried 20 cm long wood blocks were placed in a test chamber; VMs were collected with the solid phase micro extraction fiber and analyzed by gas chromatography-mass spectrometer. Average emission of nine different VMs, α- and β-pinene, 3-carene, limonene, terpinolene, myrcene, camphene, ortho -cymene and ƴ-terpinene, decreased 68–87% during one-year long storage. Moisture content (MC), knots, tree species and tree individual affected the VM emissions from wood. When a certain level of MC (12%) was reached, the VM levels decreased, but the method of drying (industrial or dried in storage) did not affect the amount of released VMs. Rehydration and dehydration increased and decreased VM emissions, respectively. Moreover, two of the eight Scots pine heartwood planks contained almost no 3-carene while being the most abundant monoterpene in the others.

April 20, 2021

The impact of acid hydrolysis conditions on carbohydrate determination in lignocellulosic materials: a case study with Eucalyptus globulus bark

Ricardo Jorge Oliveira, Bruna Santos, Maria J. Mota, Susana R. Pereira, Pedro C. Branco, Paula C. R. Pinto

Page range: 957-967

Abstract

Lignocellulosic biomass represents a suitable feedstock for production of biofuels and bioproducts. Its chemical composition depends on many aspects (e.g. plant source, pre-processing) and it has impact on productivity of industrial bioprocesses. Numerous methodologies can be applied for biomass characterisation, with acid hydrolysis being a particularly relevant step. This study intended to assess the most suitable procedures for acid hydrolysis, taking Eucalyptus globulus bark as a case study. For that purpose, variation of temperature (90–120 °C) was evaluated over time (0–5 h), through monosaccharides and oligosaccharides contents and degradation. For glucose, the optimal conditions were 100 °C for 2.5 h, reaching a content of 48.6 wt.%. For xylose, the highest content (15.2 wt.%) was achieved at 90 °C for 2 h, or 120 °C for 0.5 h. Maximum concentrations of mannose and galactose (1.0 and 1.7 wt.%, respectively) were achieved at 90 and 100 °C (2–3.5 h) or at 120 °C (0.5–1 h). These results revealed that different hydrolysis conditions should be applied for different sugars. Using this approach, total sugar quantification in eucalyptus bark was increased by 4.3%, which would represent a 5% increase in the ethanol volume produced, considering a hypothetical bioethanol production yield. This reflects the importance of feedstock characterization on determination of economic viability of industrial processes.

May 14, 2021

Improved chemical pulping and saccharification of a natural mulberry mutant deficient in cinnamyl alcohol dehydrogenase

Tsutomu Ikeda, Naoki Takata, Shingo Sakamoto, Shi Hu, Nuoendagula, Shojiro Hishiyama, Nobutaka Mitsuda, Wout Boerjan, John Ralph, Shinya Kajita

Page range: 968-977

Abstract

Lignin content and its molecular structure influence various wood characteristics. In this study, the anatomical and physicochemical properties of wood derived from a naturally occurring mulberry mutant deficient in cinnamyl alcohol dehydrogenase (CAD), a key enzyme in lignin biosynthesis, were analyzed using conventional staining assays on stem sections, length and width measurements of xylem fiber cells, wood pulping and saccharification assays, and sugar compositional analysis of extractive-free wood powder. The present data indicate that the mutation in the CAD gene leads to improved wood delignification efficiency, increased pulp yield under alkaline pulping conditions, and enhanced saccharification efficiency following alkaline pretreatment. This study opens up new avenues for the multipurpose use of the mulberry CAD-deficient mutant as a raw material for biorefinery processes, in addition to its traditional use as a favored feed for silkworms.

Ahead of Print / Just Accepted

Ahead of Print / Just Accepted

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5-year Impact Factor	2.363
Cite Score	3.8
Impact Factor	2.393
SCImago Journal Rank	0.518
Source Normalized Impact per Paper	0.960
Journal Citation Indicator	1.07

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Editorial

Editor-in-Chief
Lennart Salmén, Sweden

Editorial Board
G. Daniel, Sweden
H. Militz, Germany
T. Rosenau, Austria
H. Sixta, Austria
T. Vuorinen, Finland

Advisory Board
D.S. Argyropoulos, USA
M.Y. Balakshin, USA
J. Barnett, UK
I. Burgert, Switzerland
D.V. Evtuguin, Portugal
C.E. Frazier, USA
K. Fukushima, Japan
G. Gellerstedt, Sweden
W. Gindl-Altmutter, Austria
W.G. Glasser, USA
B. Holmbom, Finland
A. Isogai, Japan
J.F. Kadla, Canada
M. Kleen, Finland
G. Koch, Germany
D. Lachenal, France
S.D. Mansfield, Canada
J.J. Morrell, USA
P. Niemz, Switzerland
A. Potthast, Austria
A.J. Ragauskas, USA
J. Ralph, USA
R.W. Rice, USA
U. Schmitt, Germany
T.P. Schultz, USA
J. Sipilä, Finland
J. Welling, Germany
S.M. Willför, Finland
H. Yoshihara, Japan

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Holzforschung
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E-mail: Holzforschung.Editorial@degruyter.com

(Deutsch)

Online ISSN: 1437-434X
Print ISSN: 0018-3830
Type: Journal
Language: English
Publisher: De Gruyter
First published: January 1, 1947
Publication Frequency: 12 Issues per Year
Audience: Researchers in the field of biology, chemistry, physics and technology of wood and wood components

Holzforschung

Cellulose – Hemicelluloses – Lignin – Wood Extractives

Frontmatter

Ultrasound to estimate the physical-mechanical properties of tropical wood species grown in an agroforestry system

Abstract

Natural durability and improved resistance of 20 Amazonian wood species after 30 years in ground contact

Abstract

Cellular-level chemical changes in Japanese beech (Fagus crenata Blume) during artificial weathering

Abstract

Evaluation of water related properties of birch wood products modified with different molecular weight phenol-formaldehyde oligomers

Abstract

Superhydrophobic wood surface fabricated by Cu2O nano-particles and stearic acid: its acid/alkali and wear resistance

Abstract

Dynamic strength properties and structural integrity of wood modified with cyclic N-methylol and N-methyl compounds

Abstract

Indoor storage time affects the quality and quantity of volatile monoterpenes emitted from softwood timber

Abstract

The impact of acid hydrolysis conditions on carbohydrate determination in lignocellulosic materials: a case study with Eucalyptus globulus bark

Abstract

Improved chemical pulping and saccharification of a natural mulberry mutant deficient in cinnamyl alcohol dehydrogenase

Abstract

Superhydrophobic wood surface fabricated by Cu₂O nano-particles and stearic acid: its acid/alkali and wear resistance