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The drying process was examined relative to parameters’ influence on the deformation and surface layer color changes of beech wood (Fagus sylvatica L.) and oak wood (Quercus robur L.). The goal was to analyze the impact of drying process conditions, wood and growth rings types, and load on the deformation and surface color changes of drying thin wooden elements. A further aim was to reduce the time of the lamella drying and minimize wood products defects. During each drying, 40 pieces of wood were dried, divided into two groups. For the first group, 30 pieces were dried under a uniformly distributed load of approximately 50 kg, while for the second group, 10 samples were dried without weight. The lamellas dried under load exhibited fewer cup, bow, and twist deformations than the lamellas dried without load. Cracks in the dried lamellas occurred comparably in those dried under and without load. Color changes in the specimens before and after drying were observed and measured. The differences in colorimetric parameters (a, b, and L) between wood without defects and with defects were less marked after drying than before drying. The color changes were only noticed in the surface layers of the specimens.

The necessity of economical and rational use of natural energy sources caused a rapid development of research on the possibilities of using non-conventional energy resources. Taking the above into account, a new technological process of thermochemical conversion of biomass and communal waste, commonly known as High Temperature Air/Steam Gasification (HTA/SG) and Multi-Staged Enthalpy Extraction Technology (HTAG-MEET), was developed. In relation to traditional techniques of gasification or combustion of hydrocarbon fuels, the presented concept is characterized by higher thermal efficiency of the process, low emission of harmful compounds of carbon, sulfur, nitrogen, dioxins, furans and heavy metals. The use of a high-temperature gasification factor causes an increased thermochemical decomposition of solid fuels, biomass and municipal waste into gaseous fuel (syngas), also with increased hydrogen content and Lower Calorific Value (LCV). In this study, the possibility of using a batch type reactor (countercurrent gasifier) was analyzed for gasification of biomass and municipal waste in terms of energy recovery and environmental protection. The proposed research topic was aimed at examining the possibility of using the thermal utilization of biomass and municipal waste through their high-temperature decomposition in the presence of air, a mixture of air and steam. The main goals of the research were achieved during the implementation of several parallel stages of the schedule, which included, primarily: (a) study of the possibility of using thermal utilization of biomass and municipal waste through their high-temperature gasification in the presence of air or a mixture of air and steam and, secondary (b) analytical and numerical modeling of high-temperature gasification of biomass and municipal waste with the use of ANSYS CFD Fluent 6.3 software. Selected results of the experimental and numerical studies are properly presented. The higher temperature gasification concept shows the capability of this technology for maximizing the gaseous product yield in an up-draft fixed bed gasifier. It was also observed that at a high temperature, steam addition contributed to the thermal conversion of biofuels to gas with higher production of hydrogen.

The thermal treatment of wood changes its structure due to the degradation of wood polymers (cellulose, hemicellulose and lignin), so the physical properties of wood are either improved or degraded. Color changes apply not only to natural wood, but also to such wood composites for which some amount of glue is used in their construction (e.g., plywood, blockboard or laminboard). This article is focused on the analysis of hornbeam and field maple wood color changes influenced by drying temperature. Two types of drying modes were used: hot-air mode where the temperature of the drying environment was 60 °C, and high-temperature mode with a drying temperature of 120 °C. The drying mode was divided into two phases depending on the moisture content of the wood. The compared woods had similar values of color coordinates at the beginning of drying. During hot-air drying, the largest changes in color coordinates occurred during the first 24 h. The total color difference between the color at the end and the beginning of drying was 7.3 for hornbeam and 11.1 for maple. The overall color difference between the compared woods was minimal. During high-temperature drying (120 °C), the color changes of the dried woods were more pronounced. In the case of maple wood, there was a very significant change in color and the value of ΔE* was twice as high as for hornbeam. The total color difference between the color at the end and at the beginning of drying was 8.7 for hornbeam and 18.9 for maple.

The influence of the impregnation process of pine wood (Pinus sylvestris L.) samples on the electrical resistance changes and the moisture-content measurement accuracy is presented in this paper. In this study, the resistances of impregnated and nonimpregnated green pine timber harvested from northern Poland were compared. An impregnation method based on a vacuum-pressure chamber was used. Copper salts were applied as the impregnated solutions. The obtained results of the electrical resistance comparison showed a dependence of wood resistance on the moisture content. Higher conductivity occurred in impregnated wood samples filled with copper salt compared with wood samples without impregnation. Noticeable differences in the electrical resistance values were observed when the wood moisture content was significantly above the Fibre Saturation Point (FSP).

The technology of high temperature drying has a great influence on dimensional and selected physical changes in tension wood. Article is focused on the measurement properties such as moisture content, color changes and longitudinal warping. The quality of beech wood is determined based on structure and properties of wood, frequency of defects in wood material. The tension wood is considered as an important wood defect causing negative alterations in solid wood quality and limits industrial application of wood. The different values of longitudinal warping which were measured after drying were higher in tension wood than in normal wood. Impact of radial and tangential angle of growth rings is non-significant factor.

Beech wood has a high frequency of defects such as red heartwood, reaction wood (tension wood). For the experimental measurements four logs without visible defects like red heartwood, which can noticeably affects the measurements' results were qualified. The drying medium temperature in the first phase of the process before the moisture content of the specimens fell below the FSP was maintained at 45 °C. Then, the temperature was gradually increased to the maximum value 65 °C. The results showed that different initial wood moisture content does not affect to final value of tension and normal wood. The colorimetric parameter L* was much higher for tension wood. After steaming, there were greater differences in the colorimetric parameters, respectively, a* and b*. After drying the difference of all colorimetric parameters between tension and normal wood was significantly less. The color changes were only noticed in the surface layers of specimens. Differences were small, and thus, the impact of the ...

Wood pellets as biofuel are more and more used in small heat sources in Europe. Standard wood pellets are produced from wood sawdust without bark. The paper deals about the impact of bark in wood pellets on their properties and combustion process. Special attention in this work is paid to production of particulate matter during combustion of wood pellets depending on bark content. There were experimentally produced spruce wood pellet samples with 0, 1, 2, 5, 10, and 20% content of bark. The density, moisture content, calorific value, ash content, and ash fusion temperature were detected on produced samples. Then, the combustion took place in a small heat source which was tested on an experimental device designed for the measuring of heat output and emission production. Based on the achieved results, we can conclude that bark content in pellets has a significant impact not only on wood pellet properties but also on performance and environmental characteristics of pellets. The results showed that growing bark content has negative impact on wood pellet properties, mainly decrease calorific value and ash fusion temperature, and increase ash content. Growing bark content in wood pellets also decreased heat output of heat source and increased gas emissions and particulate matter production.

The aim of the article is to present the results of moisture content of wood during and after the high temperature steam and air-steam mixture drying processes and after an open air drying process. The knowledge of moisture content changes of wood in the process of its drying is one of important parameter to economy drying process and to keep the quality of dried wood. Wood samples, namely spruce (Picea abies K.) and beech (Fagus silvatica L.) from the northern part of Poland, were subject of steam, air-steam mixture and air drying respectively with a temperatures about 105, 80 and 25°C. The samples of thickness 70 mm and length about 1050 of spruce and about 1500 mm of beech were used. They were machined by the modern narrow-kerf frame sawing machine. Temperature of the cross-section of dried wood was measured by thermocouples, wood moisture content was determined during process using moisture sensors. Measurements of moisture content for steam dried and air dried samples, as reference, allowed t...

This study examined the changes in the properties of beech wood (Fagus sylvatica L.) after intense drying. Beech wood with false red heartwood was selected as the test specimen. The test samples had dimensions of 50 mm thickness, 180 mm width, and 350 mm length. The specimens were divided into two groups, false red heartwood and sapwood. These specimens were selected with different angles of the growth rings (radial and tangential). The results showed that samples with red heartwood, in comparison to samples with sapwood content, had a remarkable effect in covering. Observation of specimens with false red heartwood and sapwood before and after drying process revealed significant differences in color changes and measured values during the covering-slicing test, but not between samples with different growth ring angles.

The ruins of the medieval castle from the 14th century are the subject of the analysis presented in this paper. The castle is located in Zabkowice Slaskie (known as Frankenstein), in the Sudeten Foreland (Poland) on the former Wroclaw-Prague trade route. Destroyed and rebuilt several times, it was a remarkable work of Renaissance architecture and in its most representative form from the beginning of the 16th century. The castle was abandoned at the end of the 18th century and since then has fallen into destruction, finally being qualified as a permanent ruin. In 2011, conceptual and design conservation works were undertaken to secure the facility in order to make the ruins available for tourists. At the same time new buildings were introduced to the castle area to fulfill a variety of new utility functions. The authors of this paper have focused on the architectural and structural solutions of the adaptation of the ruins in the northwestern part of the castle, proposing the concept of a self-supporting laminated timber construction for a tourist information and exhibition center building as an element which can attracts visitors. Inspiration for the proposed concept of adaptation was the execution on the site of the ancient ruins of a new construction of laminated timber structures, which has recently become very popular in Europe.

Masonry arches and vaults often need repair and/or strengthening because of damage which can occur due to such factors as material degradation, forced displacements of supports or increase of service loads, which can finally cause their failure. A possible solution for preventing failure or to reinforce already cracked arches or vaults can be properly applied FRP composites – strips or sheets. The basis of analytical and numerical models of FRP and masonry, as well as some results of selected 3D numerical calculations of masonry cross vaults strengthened with FRP strips are presented in the paper.

The impact of the full-cell impregnation of pine wood was investigated with respect to changes in electrical resistance and the accuracy of moisture content measurement. This study compared the resistance of impregnated and untreated pine timber harvested from the northern part of Poland (Pomeranian region). The wood was impregnated by the vacuum-pressure method. The preservative (TANALITH E 3475) and coloring (TANATONE 3950) agents were based on copper salts. The results showed a dependence of wood resistance as a function of the moisture content. Impregnated and not treated wood samples were used. This result reflects the greater conductivity of the impregnate solution (based on copper salt) than the water. This phenomenon became more distinctive as moisture content value was above the Fiber Saturation Point (FSP).

The article presents the results of experimental examination of the wood chip suction system in the existing sliding table saw before and after its modification. The studies focused on the extraction hood of the mentioned system. The methodical experimental research of the pressure distribution inside the hood during wood chip removal for the selected rotational speed of saw blades of 3500 and 6000 min-1 with a diameter of 300 mm and 450 mm were carried out. The analysis of the results allowed estimating the areas with insufficient vacuum pressure hindering the organized transport of wood chips in the sliding table saw. That pressure was the main factor influencing the decision to adjust the hood construction. To achieve the efficient performance, several changes in the hood geometry were implemented. The results obtained from the experiments were used at the stage of shape modification of the extraction hood. As a result, a new design of the chip suction system was obtained, vastly improving the chip extraction from the tool., U radu su prikazani rezultati eksperimentalnog istraživanja sustava za odsis drvnih čestica na stolnoj kružnoj pili prije njegove izmjene i nakon nje. Istraživanja su bila usmjerena na usisno ušće istraživanog sustava. Provedeno je metodološko eksperimentalno istraživanje raspodjele tlaka unutar usisnog ušća tijekom rada sustava za odsis drvnih čestica pri brzini vrtnje kružne pile od 3500 i 6000 min-1 i uz promjer lista pile od 300 i 450 mm. Analiza rezultata omogućila je procjenu područjâ s nedovoljnim podtlakom unutar kojih je onemogućen učinkovit odsis drvnih čestica na stolnoj kružnoj pili. To je i bio glavni razlog odluke o prilagodbi konstrukcije usisnog ušća. Kako bi se postigao učinkovit odsis drvnih čestica, napravljeno je nekoliko promjena u geometriji usisnog ušća. Rezultati dobiveni eksperimentalnim istraživanjem upotrijebljeni su u fazi modificiranja oblika usisnog ušća. Kao rezultat toga dobiven je novi dizajn usisnog ušća kojim je znatno poboljšan odsis drvnih čestica iz radnog prostora alata.

The paper presents results of computer modelling and analysis of typical precast large-panel multi-storey apartment buildings. Two- and three-dimensional FEM models of an exemplary building as well as ideal and degraded models of horizontal joints are defined. Results of numerical analyses are discussed for different types of loads.

Industrial buildings from the beginning of the 20th century can still be found in Polish cities. Some of them have already been listed as heritage objects. Those structures where new technical solutions and materials were used, for example concrete, are especially interesting. Some of those objects are currently under a process of restoration with the aim to reconstruct and adapt them for completely new and different utility functions but without losing their important heritage value. In this paper, elements of the assessment procedure of the technical state regarding a historical survey, material examination and structural analysis, are presented on the example of two selected industrial buildings in which reinforced concrete was used as the main structural material. The main aim of the performed diagnostic procedure was verification of the load-bearing capacity of structures of the examined buildings. The calculation made confirmed that in case of not damaged concrete elements they have enough capacity to carry on newly designed loads. That confirmed that old concrete structures, especially in industrial buildings, sometimes have capacity reserves. On the other hand it allows to perform the design of less invasive renovation works or strengthening solutions with the aim to respect their industrial heritage value.

Several properties of wood including the cutting power requirements can be correlated to wood density. Therefore, according to the literature, the cutting power requirements (and/or cutting forces) could be computed as a function of the wood specific gravity. This research shows that such an approach, based solely on specific gravity, may be considered a rather rough and imperfect estimate of cutting power. Samples of Scots pine (Pinus sylvestris L.) wood from different provinces in Poland with varying densities were machined on a sash gang saw. The average cutting force versus average wood density (estimated with the standard gravimetric method) was calculated, and the local cutting forces correlated to the local wood density. The average values of the cutting forces measured at selected points along the sample’s length were calculated by linear regression to the X-ray absorbance (density) estimated by means of X-ray radiography.

Artykul dotyczy badan eksperymentalnych i numerycznych intensyfikacji wymiany ciepla w modelowym wymienniku ciepla z turbulizatorami przeplywu dla roznej geometrii turbulizatorow. Do badan eksperymentalnych wykorzystano termografie cieklokrystaliczną a modelowanie fizyczne wykonano za pomocą kodu komputerowego FLUENT.

The paper lays emphasis on the importance of the distribution of actants in bilingual translation from German into Polish and Polish into German. A contrastive analysis can be carried out in order to show the possibility and/or necessity of ordering actants in particular sentence patterns. This ordering will be determined by a number of parameters, such as a specific word order type (e.g. basic, neutral, pragmatic), morphological representation of actants, and, in German, the definiteness parameter. In particular, the paper focuses on the system compensation of grammatical category definiteness in the Polish language and its practical applications in the process of translation.