scholarly journals CHANGES IN GROSS CALORIFIC VALUE OF THERMALLY TREATED SCOTS PINE (PINUS SYLVESTRIS L.) AND SESSILE OAK (QUERCUS PETRAEA L.) WOOD AND THEIR EXPLANATION USING FTIR SPECTROSCOPY

Wood Research ◽  
2021 ◽  
Vol 66 (2) ◽  
pp. 243-254
Author(s):  
Emília Orémusová ◽  
Eva Výbohová

Scots pine (Pinus sylvestris L.) and Sessile oak (Quercus petraea L.) wood were thermally treated in an oven at the temperatures of 160°C, and 200°C under atmospheric pressure in the presence of air for 3 and 9 hrs. The mass loss and gross calorific value were determined. Non-treated wood samples achieved a gross calorific value of 22 193 J.g-1 for pine wood and 19 277 J.g-1 for oak wood. Whereas the calorific value of pine wood with increasing severity of treatment decreased, in the case of oak it increased. The mass loss increased with increasing treatment severity by both wood species. Mentioned differences in pine and oak wood behaviour using ATR-FTIR spectroscopy were explained. In the case of pine wood with increasing temperature and time of exposure a decrease of resin acids was observed. This may be contributed to decrease in GCV. In the case of oak wood, mainly at temperature of 200°C the degradation of hemicelluloses was observed that results in relative increasing in the lignin content with followed increase in the GCV.

Holzforschung ◽  
2007 ◽  
Vol 61 (5) ◽  
pp. 600-604 ◽  
Author(s):  
Outi Karppanen ◽  
Martti Venäläinen ◽  
Anni M. Harju ◽  
Stefan Willför ◽  
Suvi Pietarinen ◽  
...  

Abstract There is wide variation in the extractive content and decay resistance of Scots pine (Pinus sylvestris L.) heartwood. The heartwood is not visible in standing trees and only poorly visible in timber. Therefore, it is difficult to identify extractive-rich trees, and consequently the most decay-resistant heartwood. On the other hand, knots are clearly visible in standing trees and timber. In the present paper we studied the possibility of measuring the decay resistance of Scots pine heartwood indirectly on the basis of the extractive concentration of knotwood. The material investigated consisted of 40 felled trees with a wide between-tree variation for extractive content and decay resistance of their heartwood. The extractive content of knotwood was found to be four- to five-fold higher than that of heartwood. Statistically significant correlations were found between the mass loss of heartwood and the concentrations of total phenolics and stilbenes in knotwood (r=-0.54, P<0.001 and r=-0.40, P=0.011, respectively), and for the concentration of total phenolics (r=0.42, P=0.008) and stilbenes (r=0.39, P=0.012) between heartwood and knotwood. We suggest further development of this technique in the context of rapid industrial screening of durable pine heartwood.


2010 ◽  
Vol 18 (4) ◽  
pp. 281-287 ◽  
Author(s):  
Ingrida Pliopaitė Bataitienė ◽  
Donatas Butkus

Artificial radionuclides entered the environment mostly as a result of nuclear explosions, accidents at nuclear power plants and are entering due to the operation of the nuclear industry. After entering the environment, radionuclides spread globally at the world level, affect all environmental components and accumulate here. One of such environmental components is the tree. It, as if a historical chronicle, fixes the previous contamination and the former climatic conditions. One of the ways to read that chronicle is to estimate the radionuclide soil‐to‐tree transfer factors and coefficients. This work presents and analyses the experimental data of a study on the transfer of radionuclides from the soil to Scots pine (Pinus sylvestris L.). The report investigates the transfer of 90Sr and 137Cs from a soil layer of 0–20 cm to Scots pine wood. For investigation, Scots pine (Pinus sylvestris L.) was selected. Its growing site is in Alytus district, in a woody territory, where it falls into an increased radioactive contamination patch. On this growing site, sandy soils are prevailing. It is identified that 90Sr transfer factor to the pinewood under study ranges from 0.005 ± 0.002 to 0.315 ± 0.002, and transfer coefficients from (0.2 ± 0.1) •10–4 to (4.0 ± 0.6) •10–4m2/kg. Meanwhile, the coefficients of 137Cs transfer from the soil to Scots pine wood ranges from – (4.0 ± 1.0) • 10–4 m2/kg to (8.0 ± 2.0) • 10–4 m2/kg. The identified mean transfer coefficients of 137Cs are approximately five times higher than mean coefficients of 90Sr transfer from soil to wood. Santrauka Dirbtines kilmes radionuklidai daugiausiai i aplinka pasklido del vykdytu branduoliniu sprogdinimu, avariju atominese elektrinese ir tebepatenka veikiant branduolinei pramonei. Pateke i aplinka, radionuklidai globaliai pasklinda ir veikia visus aplinkos komponentus bei juose kaupiasi. Vienas iš tokiu aplinkos komponentu yra medis. Jis tarsi istorijos metraštis fiksuoja buvusia užtarša ir buvusias klimatines salygas. Vienas iš būdu perskaityti ši metrašti – radionuklidu pernašos iš dirvožemio i medi faktoriu ar koeficientu vertinimas. Darbe pateikiami ir analizuojami eksperimentiniai radionuklidu pernašos iš dirvožemio i paprastaja puši (Pinus sylvestris L.) duomenys. Nagrinejama 90Sr ir 137Cs pernaša iš 0–20 cm dirvožemio sluoksnio i paprastosios pušies mediena. Tirti parinkta paprastoji pušis (Pinus sylvestris L.). Jos augaviete yra Alytaus apskrityje miškingoje teritorijoje, kuri patenka i didesnes radioaktyviosios užtaršos zona. Šioje augavieteje vyrauja priesmelio tipo dirvožemiai. Nustatyta, kad 90Sr pernašos i tiriamaja pušies mediena faktorius kinta nuo 0,005±0,002 iki 0,315±0,002, o pernašos koeficientai – nuo (0,2 ± 0,1)•10–4 iki (4,0±0,6)•10–4 m2/kg. 137Cs pernašos iš dirvožemio i paprastosios pušies mediena koeficientai kinta nuo (4,0±1,0)•10–4 m2/kg iki (8,0±2,0)•10–4 m2/kg. Nustatyti 137Cs pernašos vidutiniai koeficientai yra apytiksliai 5 kartus didesni nei vidutiniai 90Sr pernašos iš dirvožemio i mediena koeficientai. Резюме Искусственные радионуклиды в окружающей среде появились вследствие ядерных взрывов, аварий на атомных электростанциях и выпадений при работе ядерной промышленности. Радионуклиды распространяются в атмосфере и накапливаются в компонентах окружающей среды. Одним из компонентов окружающей среды являются деревья. Они как бы записывают историю случившегося загрязнения окружающей среды и климатические условия прошлого. Один из способов прочтения такого ежегодника – изучение факторов или коэффициентов переноса радионуклидов из почвы в деревья. В статье анализируются экспериментальные данные о поступлении радионуклидов в сосну (Pinus sylvestris L.) из почвы. Изучается перенос 90Sr и 137Cs из слоя почвы толщиной 0–20 см в компоненты сосны. Местом роста анализируемой сосны (Pinus sylvestris L.) послужила лесная местность в Алитусском районе, в которой после Чернобыльской катастрофы зафиксировано повышенное радиоактивное загрязнение. На этом участке доминирует супесь. Было установлено, что фактор передачи 90Sr из почвы в сосну варьирует от 0,005±0,002 до 0,315±0,002, а коэффициенты – от (0,2 ± 0,1) · 10–4 до (4,0±0,6) · 10 –4 m 2 /кg. Коэффициент переноса 137Cs из почвы в древесину сосны варьирует от (4,0±1,0) · 10–4 m 2 /kg до (8.0±2.0) · 10–4 m 2 /кg. Установлено, что средний коэффициент переноса 137Cs из почвы в древесину сосны (Pinus sylvestris L.) примерно в 5 раз больше, чем коэффициент переноса 90Sr.


Holzforschung ◽  
2005 ◽  
Vol 59 (2) ◽  
pp. 183-189 ◽  
Author(s):  
Åsa Rydell ◽  
Mikael Bergström ◽  
Torbjörn Elowson

Abstract The durability of 566 Scots pine (Pinus sylvestris) samples was tested during a period of 9 years of exposure to weather in Sweden. The parameters investigated were heartwood/sapwood, origin, surface treatment, end-seal, storage and drying method, annual ring width and density. The weight was measured on 67 occasions during 9 years in order to assess the moisture content of the samples. The mass loss was determined for each sample at the end of the trial. Sapwood had a higher moisture uptake and a higher mass loss compared with heartwood. Even if sapwood was painted with an impermeable paint and then end-sealed, it still had higher average moisture content than heartwood. The results also demonstrated that sapwood was more sensitive to different handling conditions than heartwood. Sapwood was sensitive to air-drying and water storage, which was evident in the higher moisture uptake. In terms of mass loss, some differences were evident but they were not statistically significant due to the large standard deviation of the sapwood samples from water-stored logs. The only positive influence of water storage was on samples end-dipped in oil. One explanation could be that water storage led to increased permeability due to bacterial attack, which in turn enhanced the penetration of the oil. Heartwood had low and stable moisture dynamics during the test period, almost independent of treatment or handling conditions. No correlation with moisture uptake or mass loss was evident among annual ring width, origin or density.


Holzforschung ◽  
2012 ◽  
Vol 66 (2) ◽  
Author(s):  
Thomas K. Bader ◽  
Karin Hofstetter ◽  
Gry Alfredsen ◽  
Susanne Bollmus

Abstract Fungal degradation alters the microstructure of wood and its physical and chemical properties are also changed. While these changes are well investigated as a function of mass loss, mass density loss and changes in equilibrium moisture content are not well elucidated. The physical and chemical alterations are crucial when linking microstructural characteristics with macroscopic mechanical properties. In the present article, a consistent set of physical, chemical and mechanical characteristics is presented, which were measured on the same sample before and after fungal degradation. In the first part of this two-part contribution, elucidating microstructure/stiffness-relationships of degraded wood, changes in physical and chemical data are presented, which were collected from specimens of Scots pine (Pinus sylvestris) sapwood degraded by Gloeophyllum trabeum (brown rot) and Trametes versicolor (white rot) for up to 28 weeks degradation time. A comparison of mass loss with corresponding mass density loss demonstrated that mass loss entails two effects: firstly, a decrease in sample size (more pronounced for G. trabeum), and secondly, a decrease of mass density within the sample (more pronounced for T. versicolor). These two concurrent effects are interrelated with sample size and shape. Hemicelluloses and cellulose are degraded by G. trabeum, while T. versicolor was additionally able to degrade lignin. In particular because of the breakdown of hemicelluloses and paracrystalline parts of cellulose, the equilibrium moisture content of degraded samples is lower than that in the initial state.


2016 ◽  
pp. 37-47
Author(s):  
Miroslava Marković ◽  
Snežana Rajković

The paper examines the effects of a brown rot agent-Coniophora puteana (Schumach.) P. Karst on the mass loss and compression strength of sessile oak (Q. petraea agg) wood. The wood mass loss of Q. petraea agg., caused by C. puteana amounted to 1.5, 2.12 and 2.23 after 2, 4 and 6 months respectively. The obtained values indicate that the biggest mass loss of wood occurred in the first two months. Compression strength also decreased under the influence of C. puteana. In comparison to its initial value (100%), it amounted to 92.13, 90.72 and 76.25 after 2, 4 and 6 months. The analysis of the correlation between the sessile oak mass loss-G m and compression strength decrease- p (dependent variables) and the incubation time (T-independent variable) revealed a strong correlation between the variables and the following regression equations were obtained: G m = 0.0638492 + 0.954107 x T  p = 96.328-2.666 x T


Forests ◽  
2020 ◽  
Vol 11 (10) ◽  
pp. 1033 ◽  
Author(s):  
Paweł Kozakiewicz ◽  
Agnieszka Jankowska ◽  
Mariusz Mamiński ◽  
Katarzyna Marciszewska ◽  
Wojciech Ciurzycki ◽  
...  

Scots pine (Pinus sylvestris L.) is a widespread species throughout Europe and at the same time is dominant in Polish forests and of key importance in the wood industry. Pine stands are subjected to numerous environmental stresses, and one of them is the different physico-chemical and biological properties of post-agricultural soils compared to forest soils, which may affect the properties of the resulting wood and its industrial suitability. The research material taken at the height of 1.3 m from tree trunks (breast height diameter, dbh) in the form of sections and discs was collected in an 80-year-old pine stand from four plots, representing former agricultural and ancient forest land, and two types of habitats: fresh coniferous forest and fresh mixed coniferous forest. The forest habitat trophy had a decisive impact on the dendrometric characteristics and properties of pine wood (density, modulus of elasticity, bending strength, and compressive strength along the tracheids). The history of soil use (post-agricultural or forestry) did not affect the analyzed pine wood properties. Regardless of the forest habitat type and soil type history, pine wood at the dbh height showed a variability of features typical of century-old cultivated stands. Individual pine trunks were characterized by significant individual variability.


Forests ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 879
Author(s):  
Paweł Kozakiewicz ◽  
Łukasz Tymendorf ◽  
Grzegorz Trzciński

Scots pine (Pinus sylvestris L.) is one of the most important forest tree species in Europe, and its wood is a main raw material in the wood industry of many countries of the region. The high variability of pine wood density in connection with its moisture content is a challenge in transport operations. An important part of the roundwood transport of pine wood by trucks is the transport of large-size roundwood (sawlogs). As part of the research, an analysis was carried out of the influence of absolute wood moisture content, determined in various ways, on selected truck transport parameters of large-size pine wood. The analyses of the supply of wood to a large sawmill in northern Poland took into account different seasons. The results indicate that the average moisture content of the transported pine wood is at a level of approximately 95% (determined by dry weight) and the density at 0.878 Mg m−3 (determined using the stereometric method). Quick measurement with the use of a resistance hygrometer gives significantly lower results both on the side surface and on the cross-cut end of the log. Regardless of the method of measurement, the absolute moisture content of wood in loads depends on the date of delivery (season), which is reflected in the variability of the density and weight of the loads. The indicated strong correlations between the selected, tested characteristics of roundwood transports are important for forestry practice too. It is the possibility of using the methods of quick determination of fresh wood moisture to estimate the density of wood and to predict and determine the mass of the load.


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