Papers by Keyword: Wood

Abstract: A large amount of finely dispersed manganese ore left after benefication operations or blown out from the furnaces is unsuitable for direct use in electric furnaces and blast furnaces, therefore it is necessary to granulate it in order to have the efficient use of its fine ore particles in metallurgy. To make our research more of practical use, we found it is reasonable not only work over manganese fines sintering but also to attempt mitigating the negative effect on the environment produced by the further sintering and apply the biofuel within the total fuel mass. Under laboratory conditions, the studies have been carried out with the objective to obtain manganese sinter, in which wood biomass is applied, namely initial and pre-pyrolyzed, at temperatures of 673, 873, 1073 and 1273 K. The amount of biofuel in the sinter blend was 25 wt.%. It has been established that the biomass use causes the decrease in the specific capacity of the sintering plant. However, for the efficient manganese ores sintering process, the biofuel of high pyrolysis temperature of 1273 K is required. To achieve the specific capacity and the yield to be as high as those when coke breeze is only used, the amount of the biofuel for manganese ore sintering should be less than 25 wt.% of the solid fuel. Additionally, it has been revealed that the further increase in the biofuel ratio in the total fuel amount is possible on condition that its reactivity is decreased, or larger particles of the biofuel are used.

Abstract: The article presents the results of using activated lingo-cellulosic material, obtained by the method of steam explosion treatment, as the basis for the production of composite pressed boards without a binder. The influence of steam explosion treatment modes on the physical and chemical properties of the wood pulp product and the strength properties of the resulting board materials is considered.

Abstract: The aim of this research is to investigate and to evaluate the changes that occur on the surface of wood specimens, coated with three different coatings and exposed to artificial weathering. The three used coatings contain linseed oil and different types of pigments. Specimens of pine wood (Pinus sylvestris L.) were painted with one or two layers of coatings to evaluate the discoloration and changes in lightness. For all the tested coatings, discoloration and loss of lightness were observed for all specimens regardless of the applied coatings. Different rates of color changes were observed for the tested coatings. The presence of pigments in the coatings formulation delays the discoloration of wood; as also the composition of pigments plays a significant role in the process.

Abstract: In the last decades the studies on thermoplastic composites reinforced with natural fibres have been mostly focused on vegetable lignocellulosic or cellulosic fibres. These materials provide eco-sustainable solutions for a large range of applications and have been actually adopted by multiple industries. The interest on fibres of animal origin is more recent and research on composites reinforced with these fibres predominantly composed of keratin, such as wool, feathers or silk, is increasing in virtue of some advantageous properties that may overcome some of the intrinsic limitations from vegetable fibres. The combined use of vegetable and animal fibres in composites appropriate for melt blending processing is at early stages of research. After chemical treatments, the fibres of animal origin have been mostly applied as binders between vegetable fibres and polymers, not as main constituents of these composites. The use of both types of fibres simultaneously in composites of thermoplastic matrices is the subject of the present study wherein the fibres of animal origin (wool) are different kinds of residues from a textile industry and the fibres of vegetable origin (wood) are residues from carpentry activities. The chemical composition, the macro and microstructure of the fibres is analyzed, as well as that of composites that combine non-biodegradable and biodegradable polymers with diverse ratios of fibres in different conditions (wool as cards, yarns and felt cloths; wood as sawdust). The addition of coupling agents to enhance the compatibility between wool, wood and different polymers is also analysed.

Abstract: In recent years, the development of new procedures and solutions in the field of conservation has been very significant. The purpose of this article is to collect the main contributions of nanotechnology, in its multifunctional solutions applied in heritage, to offer a global vision of the state of the matter for both scientists and restaurateurs.Nanomaterials offer some advantages over traditional products, improved compatibility and efficiency and reducing the use of toxic organic solvents for humans and the environment. Solutions have been developed for both inorganic supports and organic supports for artistic, architectural and archaeological heritage. Especially relevant are the advances in consolidation processes, pH regulation and / or cleaning / elimination of alteration products on murals, frescoes or stone and in materials composed of cellulose and collagen.Also, nanotechnology is still a recent science and has yet to answer certain questions about its use protocols and reduce the possible risks to health.

Abstract: Today’s methods for producing powdered celluloses, in particular microcrystalline cellulose (MCC), from various plant raw materials, while applying new highly efficient methods for the isolation of cellulose are of a great interest. One of these methods is the production of MCC from lignocellulosic material activated by steam explosion treatment. The material obtained by this method from wood has a high reactivity, low content of residual lignin, a high specific surface, which allows to subject it successfully and efficiently to accelerated delignification or hydrolytic breakdown (degradation). This ability of the lignocellulosic material, activated by steam explosion, is the basis of this study, which provides the results of an experimental evaluation of the component and dispersion analysis of MCC, obtained from this material.

Abstract: In this paper we present the results of a study of the physical and chemical properties of activated lignocellulose obtained in the process of steam explosion treatment of various breeds of wood. It is shown that fibrous material has a high potential for scientific and commercial use: in the field of production of pulp for paper and cardboard production in a more efficient way, to obtain microcrystalline cellulose by hydrolysis, to produce coarse lignocellulosic fibers for the production of construction and insulation boards with new properties. The scope of activated lignocellulose is not limited only to these directions, but can be significantly expanded due to the competent use of its physical and chemical properties.

Abstract: The article is devoted to the study of strength and thermal insulation properties of logs OBrien. To prevent shrinkage and surface cracks it is proposed to dry logs through the through longitudinal hole. The proposed method is the method of determining geometric parameters of longitudinal openings for the drying of logs, provided that the strength of the logs for a given it load in the design of the exterior walls of the typical wooden house. The stress-strain state of round logs in the outer walls of a wooden frame with a longitudinal hole diameters was studied. It was found that the most dangerous for the considered loadings are the stresses along the contour of the holes. The dependences obtained for the appointment of the diameter and position of holes of the load acting on the beam showed that the holes can be different, depending on the position in the log height of the structure. It was justified, based on the thermal resistance from geometric parameters of round logs.

Abstract: Modern alternative to chemical methods of wood modification is heat treatment, which allows to increase biological stability, to reduce the hygroscopicity of the material and to improve the appearance of products. One of such technologies is heat treatment in liquids. However, this method is characterized by a considerable duration of the process because of cooling the material directly in the liquid. The aim of this work is to improve the technology of thermal modification of wood in liquids by reducing the duration of cooling phase without additional energy consumption. The results of experimental studies of the proposed technology of heat treatment of wood are presented. The obtained data on changes in wood density show that at increasing the average density of the material, there is a reduction in the density of its central layers that is explained by impregnation of the surface layers of wood with wood agent. It can be stated, basing on the analysis of the depth of impregnation of different wood species, that the rate of flow of impregnating liquid is directly proportional to the temperature of heat treatment, in the same time the depth of penetration of the treatment agent into the lumber depends not on treatability of natural wood but its basic density. Therefore, heat treatment of wood in hydrophobic liquids is more rational to use for hard species with greater density, and consequently, a smaller depth of penetration of the treatment agent, which will reduce the flow rate of hydrophobic liquid when carrying out the process and avoid large losses of material during subsequent mechanical processing.

Abstract: The article describes the technological features of the bonding of a new type of finishing materials made of glued laminated wood – relief plywood. The relevance of the topic and relevance of the questions is dictated by the need to involve more in processing underutilized at the present time of wood of soft deciduous species. Analytical review of publications of Russian and foreign authors showed that the most of the research has been focused on increasing the strength of structural materials and improvement in the appearance of finishing materials received considerably less attention. Therefore, the aim of the research is theoretical and experimental substantiation of the scientific principles enhance the appearance of plywood production by developing three-dimensional pattern on the front surface. Scientific novelty has discussed in the article questions of modeling of processes of formation of the relief. The article theoretically justifies the conditions for obtaining relief on the front surface of the new finishing material without breaking. The practical significance of the research is to study the possibility of improving the appearance of finishing materials with a homogeneous texture to the wide usage of wood of soft hardwoods in the timber and construction industry.