Wood Science

Flue gas emissions and particle size distribution were investigated during combustion experiments of wood, forest residue and mixtures of these two. The combustion experiments were carried out in a grate fired multi-fuel reactor with and without air staging at stable operation conditions and constant temperature of 850 °C. The overall excess air ratio was held at 1.6, and the primary excess air ratio was 0.8 during air staged experiments. NOx emissions are reduced by air staging. Fly ash particle concentration of forest residues in the flue gas is lower than wood. Aerosols number increased in the staged experiments for fuel blends.

This paper is based on an evaluation of the industrialization levels and main production systems of Brazilian timber housing producers. Two methods were used to investigate this understudied topic. Literature-based projection was carried out to identify the production system of each sampled company, from the construction technique(s) produced by the same. The second method consisted of face-to-face interviews to identify the current production system of each producer. For both methodologies, the timber housing sector presented a considerable level of industrial development in view of the greater popularity of prefabrication systems. Due to admissions to enable the system identification from the literature-based projections, a result contrast in artisanal production was verified between both methodologies. Despite the sampling difference, the two methods showed typical results for the industrial processes. Thus, few artisanal developers and the visible amount of industrial-based producers could regard this sector as industrial-featured.

The aim of this work was to isolate a lectin from Myracrodruon urundeuva heartwood and to evaluate its antimicrobial activity against bacteria and fungi that attack plants, including woods. The lectin was isolated from heartwood through affinity chromatography on a chitin column monitored by hemagglutination assay. The lectin inhibited Gram-negative and Gram-positive bacteria and was more effective than antifungal Cercobin in growth inhibition of phytopathogenic fungi. The detected antimicrobial activity reveals the possible role of the lectin in the resistance of M. urundeuva heartwood against deteriorative biological agents. The M. urundeuva lectin is the first bioactive peptide found in heartwood, probably stored as a chemical protection against biodegradation.

The toxic effects of selected Malaysian timbers (Madhuca utilis, Anisoptera laevis and Endospermum malaccense) heartwood extracts were studied with the aim to determine and understanding the function of wood extracts as a natural protection against termite. The results show that no-choice experiments revealed toxic properties of all investigated extracts by the contact against Coptotermes gestroi and Coptotermes curvignathus. However, high termite mortality was only achieved with Madhuca utilis extracts and methanol solvents.

This comparative study focused on understanding the effect of coupling agent and particle size on weathering behaviour of wood polypropylene composite. Two coupling agents, namely maleic anhydride grafted polypropylene and m-TMI (m-Isopropenyl-α,α− dimethylbenzyl isocyanate) grafted polypropylene were used in preparation of the composites. The composites were exposed to outdoor conditions for one year and changes in surface colour and mechanical properties were measured after 2, 4, 8 and 12 months of natural weathering. During the initial four months of weathering considerable colour change was observed with increase in lightness. Mechanical properties were unaffected largely for the initial four months and thereafter started declining. Overall, tensile strength decreased by about 15 % and flexural strength decreased by about 8 % after one year of weathering. The flexural modulus also decreased by about 10 %. Wood particle size was found to affect the aesthetic and strength of the composites after natural weathering. Coupling agents had a positive impact on mechanical properties however their influence on weathering degradation was not noticeable.

Chemical characteristics of wood are used in this study for plant taxonomy classification based on the current Angiosperm Phylogeny Group classification (APG III System) for the division, class and subclass of woody plants. Infrared spectra contain information about the molecular structure and intermolecular interactions among the components in wood but the understanding of this information requires multivariate techniques for the analysis of highly dense datasets. This article is written with the purposes of specifying the chemical differences among taxonomic groups, and predicting the taxa of unknown samples with a mathematical model. Principal component analysis, t-test, stepwise discriminant analysis and linear discriminant analysis, were some of the chosen multivariate techniques. A procedure to determine the division, class, subclass, order and family of unknown samples was built with promising implications for future applications of Fourier Transform Infrared spectroscopy in wood taxonomy classification

The effects of wollastonite fibers on the physical and mechanical properties of medium-density fiberboards composed of wood fibers with up to 10 % camel-thorn chips were studied. Approximately 30 % of the wollastonite fibers were less than 100 nm while the remainder were less than 1 μm. Wollastonite fibers significantly improved most of the physical and mechanical properties while addition of camel-thorn produced more variable effects on panel properties. Up to 10 % camel-thorn could be added to panels without negative effects. A combination of 10% camel-thorn and 5% wollastonite fibers produced panels with the best properties.

Los objetivos del trabajo fueron 1- Determinar los patrones de variación axial y radial de la densidad de la madera y longitud de fibras en el fuste de Robinia pseudoacacia, 2- Determinar la edad de transición entre madera juvenil y madera madura, 3- Construir un modelo descriptivo de distribución de la madera juvenil en el fuste en base a la densidad de madera y longitud de fibras. Se cortaron rodajas a 4 alturas en el fuste (0,3 m; 1,3m; 2,3m y 4m a partir del suelo) en 10 árboles (7-15 años) implantados en Buenos Aires, Argentina. Se determinó la densidad normal12% y la longitud de fibras en probetas radiales obtenidas cada 3 anillos de crecimiento en todas las alturas. La densidad de la madera mostró una homogeneidad de los valores a lo largo del fuste comercial (variación axial), con un rango que la clasifica como madera semi-pesada (750 - 823 kg/m3). La longitud de fibras mostró aumento radial de sus valores de médula a corteza y sin variaciones axiales. El modelo de madera juvenil se asemeja al modelo de cilindro central pero de menor diámetro en el ápice. El cono juvenil se formaría hasta la edad de 3-6 años.

Furfurylation is a modifi cation process carried out in order to improve the biological resistance and dimensional stability of wood. In this research work, a three-year outdoor weathering test of furfurylated wood was performed using the following wood materials: a deck of furfurylated radiata pine (Pinus radiata), a deck of furfurylated maple (Acer spp.), a deck of furfurylated southern yellow pine (Pinus spp.), and a control deck of Ipê wood (Handroanthus spp.) that was used for comparative reasons. The decks, without any protection or finishing, were exposed for 36 months in Karditsa, Greece in order to evaluate some physical and structural properties of wood such as colour, staining, distortion, surface cracking and end splitting. All tested decks exhibited colour changes that were perceptible by the naked eye and much higher during the fi rst twelve months of weathering. The three furfurylated wood decks showed smaller total colour changes as compared to those of Ipê control deck. In respect to surface cracking, furfurylated radiata pine deck generally showed minor surface cracks, while furfurylated maple deck presented the lowest degree of surface and end splitting. In overall, the furfurylated wood
decks tested performed very well and showed no signs of black staining (except for the southern yellow pine deck)
and no fungal or mould decay after three years of outdoor exposure.

Kayu merupakan komoditas alam yang hingga saat ini masih dipilih sebagai bahan bangunan dan meubel karena beberapa keunggulannya yaitu, warna, corak, kekuatan serta mudah dalam pengerjaan.. kekurangan dari produk kayu kapur (Dryobalanops sp) yaitu mudah mengalami penurunan kualitas akibat dari faktor kimia, fisika, atau biologi. Salah satu agen penyebab kemunduran yaitu jamur Schizhophyllum commune dapat menyebabkan kehilangan berat hingga 14,14%. Pengujian Kehilangan berat kayu dilakukan dengan inokulasi jamur S.commune menggunakan media PDA (Potato Dextrose Agar) dan diinkubasi selama 4 minggu, Pengujian nilai kerapatan kayu dilakukan dengan menggunakan standar jerman DIN 32182. Hifa jamur S.commune yang menyerang kayu kapur (Dryobalanops sp) dapat dengan mudah terlihat pada sel pori yang selanjutnya hifa melakukan penetrasi antar sel pori serta menyebar ke segala arah. Kehilangan berat kayu kapur tertinggi sebesar 0,77% dan terendah 0%.

This work concerns basic research on the concept of wood hardness in a sense similar to Brinell or in the modified sense of Monnin. The experimental part of this article is based on research carried out on beech wood with six indenters: three ball indenters of 10, 15 and 30 mm and three cylindrical indenters of 10, 15 and 30 mm. On the basis of measurements for a wide range of loads, relations analogous to Meyer power law of were obtained, with the exponent determined both for balls equal to 5/2 and for cylinders equal to 3/2. These exponents turned out to be exactly the arithmetic mean of exponents for ideally elastic and ideally plastic bodies. On this basis, new hardness formulae were proposed, taking into account Meyer law and the diameters of indenters. Therefore, the proposed two hardness formulae (for the ball and cylinder) are a generalization and development of Meyer hardness law.

Research on wood technological properties
using near infrared (NIR) spectroscopy has shown promising
results. The aim of this study was to evaluate the
efficiency of NIR spectroscopy for estimating chemical
properties of mangium wood (Acacia mangium). NIR
spectra were obtained from 150 wood meal samples of
mangium trees that were 5–7-years-old. A multivariate data
analysis method of partial least squares was used to
develop calibration regression models for predicting
chemical properties based on NIR spectra. The results
showed a good relationship between values derived from
laboratory analyses and those predicted by NIR spectroscopy
for a-cellulose and hemicellulose content. The calibration
models had high values for the coefficient of
determination (R2[0.80) and the ratio of performance to
deviation (RPD[2.0). Meanwhile, lignin and extractive
content were poorly predicted; calibration validation
revealed R2\0.60 and RPD = 1.0. This study indicated
that NIR spectroscopy analysis on wood meal of A. mangium
could be reliably used to predict a-cellulose and
hemicellulose.

Color of wood pellets is mainly affected by the feedstock material used for their production and which composition and characteristic affect the final product quality. Pellets made from pure wood are light in color and have low ash content, while pellets made from different mixtures of wood and bark or foliage are generally darker and richer in minerals. This study aims to verify the correlation between color and quality parameters of wood pellets available on the Italian market. All the samples were analyzed following the procedures laid down by the European Norms (EN) on solid biofuels for moisture, ash, calorific value, durability, bulk and solid density. The acquisition of the images was done with two techniques: the CIE L∗a∗b∗ color space and RGB-HSV color spaces. Canonical correlation analysis (CCA) was performed with CIE-L∗a∗b, RGB and HSV separately showing for all the color components good degree of correlation with ash content of pellets. The PCA analysis on two principal components (total explained variance: 64.2%) showed a clear color gradient moving form good to medium or low quality parameters. This pattern is confirmed by the clustering of certified pellets in the region of lightest samples. The calculation of ΔE and ΔRGB showed a good discrimination level between whole pellets samples and their sawdust, and between ones with high and low ash content. The visual predictability of pellets quality on the basis of their color is however not so sharp when considering samples with similar colors. The industrial applicability of such methods for the evaluation of pellets quality is desirable for RGB methodologies that are less expensive and more reliable in working condition, given that specific color calibration is performed.

Potential of oil palm starch from oil palm trunk as a starch based adhesive was evaluated based on collection of starch yields (grams) using two types of steeping methods of starch extraction processes. Sodium metabisulphite (Na2S2O5) was used in both methods and was differentiated by with and without the use of 0.5 % of lactic acid in soaking process. The results showed extraction of starch by steeping method with sodium metabisulphite (Na2S2O5) only, gave higher yield compared to extraction of starch by steeping method with presence of lactic acid. The important characteristics in the starch as a binder such as starch content, solid content and viscosity value were also determined in this study to evaluate the presence of lactic acid from both extraction methods

This book is written in Polish language.
This book contains two parts: a theoretical description and tasks. The theoretical part presents knowledge of wood physics, especially: hygroscopicity in wood (e.g. adsorption,  wood moisture content, fiber saturation point, equilibrium and maximum moisture content), dimensional changes (e.g. swelling and shrinking), density (e.g. porosity, specific gravity), electrical properties (e.g. electric resistance, electric capacity), heating properties (e.g. thermal conductivity, specific heat, heat of combustion) and acoustic properties of wood. There are a lot of calculation tasks (examples of application) in practical part.

The effect of microwave heating on the iodine-catalyzed acetylation of rubberwood with
acetic anhydride has been investigated. Microwave radiation was used as the heating source
for modifying specimens saturated with acetic anhydride in bulk solution (excess of reagent)
and impregnated specimens (limited supply of anhydride). Extent of modification of wood
was expressed in terms of weight percent gain (WPG) and modification was characterized
using FTIR spectroscopy. In bulk solution, microwave radiations were primarily absorbed by
anhydride solutions for heating purposes and a moderate WPG was obtained. However, when
microwave heating was used to modify impregnated wood specimens under no excess of
anhydride, a significant enhancement in degree of modification was achieved within a few
minutes. The modified wood exhibited good anti-swelling efficiency

Effect of temperature and moisture content on compression strength parallel to the grain of selected species of wood with variable density and anatomical structures
This paper presents an assessment of the effect of temperature and moisture content on compression strength parallel to the grain. The development of this field of wood science has been discussed and the collected information has been experimentally verified on the basis of eighteen selected species of wood with variable density and anatomical structures.
A satisfactory mathematical description of the phenomena relating to strength of materials was made in the second half of the 17th century, which was a stimulus also for development of research on wood. The next century saw research on compression strength of selected species of wood, however, without a due consideration of the effect of moisture content and the buckling phenomenon. In the 19th century, an explicit distinction was made between compression (crushing) of short specimens and a complex mechanism of destruction of slender elements. The turn of the 20th century is a period of an arduous basic research, i.e. determination of the characteristics of physical and mechanical properties including compression strength parallel to the grain for specific levels of moisture content of wood species from various continents. A new quality in testing the compression strength (optimisation of specimens and analysis of the effect of temperature) was forced by the needs of aviation in the first half of the 20th century. The last decades of the 20th century and the present century focus on testing of the above-mentioned characteristics of the material mainly for the purposes of wood constructions in the building industry. At present, compression strength parallel to the grain is readily used as a criterion in assessment of wood, due to the established strong correlation with other properties and simplicity of the test itself. Even so, the testing procedures are not fully standard yet, and the effect of temperature, moisture content, density and the characteristics of an anatomical structure of wood has been analysed only in a fragmentary way.
A unique testing method was developed for the purposes of this paper, with appropriate selection parameters for compression tests of clear wood “multi-twin” specimens, facilitating the examination of the effect of moisture content and temperature. Specimens obtained from a “single board” within the specific species of wood were used, which had been conditioned in groups of 10 pieces for each of the moisture content options, and subsequently heated or cooled without changing the moisture content. The specimens were destructed at a constant speed of increasing deformation equal to 2 mm∙min-1. The testing time of each of the specimens did not exceed 150 seconds.
The values determined for the eighteen species of wood, as a whole demonstrating a wide spectrum of density and variable anatomical structures, allowed to determine the averaged interactions and to describe them with simple (linear) correlations. A strong and directly proportional interaction between compression strength and dry density was established. This relationship is weaker in moist wood. As anticipated, the compression strength of wood tends to decrease, presenting an approximately linear trend, in the entire hygroscopic range along with increase of the wood moisture content, reaching the minimum value with moisture content at the fibre saturation point. Similarly, the strength tends to decrease along with increasing temperature. The effect of temperature is slightly stronger in moist wood. Irrespectively of the averaged interactions, a significant effect of individual characteristics of an anatomical structure and density of respective species of wood is observable, manifesting itself, among others, in significantly different values of conventional moisture content at the fibre saturation point or differences in changes of compression strength parallel to the grain resulting from moisture content and temperature. Various appearances and the nature of distractions of the specimens after the compression test were an evident indication of the effect of the anatomical structures and density of wood.
The correlations of the effect of temperature and moisture content on compression strength of the specific species of wood with variable density and anatomical structures will support quick testing of wood, i.e. not requiring long-term seasoning and conditioning of specimens. It will be possible to recalculate any wood compression strength indicating non-standard moisture content and temperature to the standard reference level. The testing method developed in this research work and the data obtained in this way have a significant value also for the purposes of determination of constructional timber characteristics. Considering cost-effectiveness factors, testing of small, “multi-twin” laboratory specimens and an effective transfer of the achieved results onto full-size constructional timer is more relevant.

Britain and the Mahogany Trade of the Americas in the 18th and 19th Centuries I have often wondered many things about wood. I have looked at pieces of furniture and wondered how tall the tree was that it came from. I have wondered where it was from or if birds or other animals lived among its branches. I have wondered who cut it down, who milled it, who carved it, who owned it, and who used it. Of all the wood I have wondered about, my favorite one to wonder about was mahogany. I have for all of my life been surrounded by antique British furniture. My father began importing English furniture from Liverpool at almost the exact same time I was born nearly thirty years ago, and I have played around, worked and lived with it nearly everyday since. In recent years, I decided that mahogany was my favorite, and I wanted to know more about it. I wanted to know where it grew, why the British loved it so, and why they chose it so often to make their cabinetry and furniture. I have come to learn that Great Britain's dealings in Mahogany are far more interesting and complex than I had previously imagined. Mahogany and Britain is indeed a strange and interesting affair. ​ The topic of Britain and mahogany offers insights into global trade, imperialism, race relations, and the environmental impact we as humans have on the world.

Il legno delle specie del genere Salix, di colore chiaro e lucente, a durame appena differenziato, mostra notevole omogeneità a livello anatomico, e non presenta particolari differenze tra le diverse entità tali da rendere possibile una identificazione specifica. Le caratteristiche anatomiche del legno confermano una dipendenza dall’acqua del salice più alta rispetto al pioppo.

Dimensional stability of wood plastic composites (WPCs) made from polypropylene and pine wood flour with and without coupling agent was investigated. The pine wood flour was prepared from wood chips which had been immersed, respectively, in boiling water for 1 h, 3 h, and 5 h or in distilled water for 1 day, 3 days, and 5 days at room temperature. It was found that thickness swelling (TS) and water absorption (WA) of the WPCs made using extracted wood were lower than those of WPCs produced with unextracted wood. The TS and WA values of WPCs decreased with extraction duration both for cold and hot water extraction. The effect of hot water extraction on the TS and WA properties of the WPCs was more pronounced than cold water extraction.

This paper is based on an evaluation of the industrialization levels and main production systems of Brazilian timber housing producers. Two methods were used to investigate this understudied topic. Literature-based projection was carried out to identify the production system of each sampled company, from the construction technique(s) produced by the same. The second method consisted of face-to-face interviews to identify the current production system of each producer. For both methodologies, the timber housing sector presented a considerable level of industrial development in view of the greater popularity of prefabrication systems. Due to admissions to enable the system identification from the literature-based projections, a result contrast in artisanal production was verified between both methodologies. Despite the sampling difference, the two methods showed typical results for the industrial processes. Thus, few artisanal developers and the visible amount of industrial-based producers could regard this sector as industrial-featured.

Dobór odpowiednich warunków klimatycznych w pomieszczeniach w których przechowywane jest drewno jest działaniem równie ważnym jak jego prawidłowa konserwacja. Umiejętność praktycznego zastosowania i wykorzystania odpowiednich zależności (opisanych wzorami) do rozwiązywania konkretnych zagadnień z zakresu klimatyzacji, posiadanie wiedzy dotyczącej właściwości higroskopijnych drewna, umiejętność sterowania parametrami powietrza w pomieszczeniach jest bazą do działań bardzo istotnych w zabezpieczaniu i ochronie drewna.
Zbiór stanowi uzupełnienie do podręcznika noszącego zbliżony tytuł:
„Klimat a drewno zabytkowe - dawna i współczesna wiedza o drewnie” autorstwa P. Kozakiewicza i M. Matejaka, wydanego przez Wydawnictwo SGGW w 2013 roku (wydanie IV zmienione). Zbiór zadań zawiera praktyczne ujęcie zagadnień omówionych w wyżej wymienionym podręczniku.

Stosowanie drewna konstrukcyjnego i materiałów drewnopochodnych o korzystnej charakterystyce mechanicznej, cieplnej i akustycznej jest podstawową cechą nowoczesnego, lekkiego budownictwa szkieletowego.
Z myślą o śmiałym używaniu drewna w konstrukcjach drewnianych przygotowaliśmy niniejsze opracowanie, w którym krok po kroku (od bazy surowcowej poprzez przerób po materiały finalne) przedstawiliśmy szereg istotnych i przekrojowych zagadnień z zakresu inżynierii materiałów drzewnych, stawiając szczególny nacisk na problematykę produkcji i sortowania tarcicy konstrukcyjnej. Znalazły się tu informacje zarówno z zakresu budowy, wad i właściwości drewna jak i uregulowań normalizacyjnych, a także przegląd technik przetarcia i analiza działania maszyn sortowniczych.

Waldbaden
„Shinrin Yoku stammt aus dem Japanischen und bedeutet so viel wie „Baden in der Waldluft“. Die aus dem Inselreich stammende naturbezogene Praxis ist darauf ausgerichtet, Stress zu reduzieren und das allgemeine Wohlbefinden zu stärken.“
Der japanische Begriff ist ein Hinweis, dass es darum geht, etwas Unbekanntes zu entdecken. Allein diese Wortschöpfung und Zeichenkombination weist auf die spielerischen und kreativen Elemente des Waldbadens hin.
森 林 浴
„Das erste Zeichen stellt einen Wald dar (drei Bäume), das zweite ein Gehölz (zwei Bäume) und das dritte bedeutet baden (fließendes Wasser links, rechts ein Tal).“
Im Kurs gilt es für mich, den Teilnehmenden mit knappen Hinweisen
Lust zu machen auf das Erleben im Wald. Es geht um Entschleunigung,
um ein Umschalten vom schnellen Denken zum langsamen Wahrnehmen, vom Verstehen zum Fühlen, gepaart mit einer Öffnung für eine Entdeckungsreise im Wald und bei sich selbst.

Forest bathing
"Shinrin Yoku comes from the Japanese for "bathing in the forest air." Originating in the island kingdom, the nature-based practice is designed to reduce stress and strengthen overall well-being."
The Japanese term is an indication that it is about discovering something unknown. This word creation and character combination alone indicates the playful and creative elements of forest bathing.
森 林 浴
"The first sign represents a forest (three trees), the second represents a grove (two trees), and the third means bathing (running water on the left, a valley on the right)."
In the course it is important for me to give the participants brief hints that
to whet the participants' appetite for the experience in the forest. It is about deceleration,
It is about switching from fast thinking to slow perception, from understanding to feeling, paired with an opening for a journey of discovery in the forest and in oneself.

Drewno zabytkowe stanowi majątek narodowy, i to bardzo często znacznej wartości pieniężnej. Pogarszanie się stanu fizycznego, a więc stanu zachowania drewnianych przedmiotów i obiektów muzealnych, będzie więc równoznaczne z uszczupleniem spuścizny kulturalnej. Aby do tego nie dopuścić i skutecznie przeciwdziałać niebezpieczeństwom, trzeba je dostrzegać i przewidywać, a do tego potrzebna jest ogromna wiedza o procesach zachodzących w drewnie pod wpływem czynników zewnętrznych.
W kontekście powyższego nie dziwią gorzkie słowa wypowiedziane przez jednego ze specjalistów od zagadnień konserwacji: „człowiek jest najgorszym wrogiem dzieł sztuki” (Coremans 1967). W otoczeniu ignorancji lub nieuzasadnionej pewności dokonywane są, nierzadko katastrofalne w skutkach, zabiegi konserwatorskie. Obiekty drewniane są narażane na zmienne warunki klimatyczne, które prowadzą do ich trwałych uszkodzeń. W różnych miejscach i odstępach czasowych zdarzają się te same błędy i niedopatrzenia.

Versatile, wood has been used by mankind in furniture, instruments, utensils and construction. About timber buildings, this critical review discusses their valuable and sustainable features that label their multiple options. Numerous contributions were compiled from the author's collection and prospection in relevant databases. Construction techniques were featured, vocations were identified and production systems were remarked to detail wood-based resources and residues. Discussions and suggestions were raised as promoting strategies. Secular buildings prove the convenience of wood materials in construction, since they have decent levels in sustainability, durability, stability, value added, aesthetics, strength and weight. Timber construction enables artisanal to industrial productions and traditional to contemporary techniques with different materials, sizes and architectural styles. Global barriers are marked by obscurities about logging and illegal deforestation, and deficiencies in the regulations of native species. The utilization of sustainably sourced wood, sylviculture as a viable social-economic driving force and several advantages of timber construction are positive reasons. Actions were proposed to drive policy and multiply timber buildings, since they form a promising segment for emerging bioeconomies of innovative nations. Changes in wood consumption to enhance sylviculture combined with the waste reutilization should intensify the sustainability of timber construction and establish industrial synergies.