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Properties of fiber-gypsum composite formed on the basis of hemp (Cannabis sativa L.) fibers grown in Poland and natural gypsum
: Properties of fiber-gypsum composite formed on the basis of hemp (Cannabis sativa L.) fibers grown in Poland and natural gypsum. The popularity of composites reinforced with natural fibers is constantly growing and therefore, they are a subject of many scientific works as well. An example of interesting concept is the use of hemp fibers to reinforce a gypsum matrix and therefore, presented study was aimed to determine the effect of their content on the properties of resultant composites. Moreover, the influence of setting temperature was also investigated. The scope of the research included determination of properties such as: density, setting time, bending strength, modulus of elasticity and thermal conductivity coefficient. Studies have shown that as the amount introduced fibers increases, the density of manufactured composites decreases. Furthermore, increase in the content of hemp causes a significant extension in setting time of the gypsum matrix. Based on the outcomes of mechanical properties, it was found that the optimal content of fibers is 4% and further increase in their share results in a deterioration of flexural strength characteristics. The increase in a setting temperature leads to thereduction in their bending strength and modulus of elasticity. Composites reinforced with hemp fibers demonstrate significantly improved thermal insulation properties
The Influence of Hemp Fibers (Cannabis sativa L.) on the Mechanical Properties of Fiber–Gypsum Boards Reinforcing the Gypsum Matrix
The modern construction industry is looking for new ecological materials (available, cheap, recyclable) that can successfully replace materials that are not environmentally friendly. Fibers of natural origin are materials that can improve the properties of gypsum composites. This is an important issue because synthetic fibers (hardly biodegradable—glass or polypropylene fibers) are commonly used to reinforce gypsum boards. Increasing the state of knowledge regarding the possibility of replacing synthetic fibers with natural fibers is another step towards creating more environmentally friendly building materials and determining their characteristics. This paper investigates the possibility of manufacturing fiber–gypsum composites based on natural gypsum (building gypsum) and hemp (Cannabis sativa L.) fibers grown in Poland. The effect of introducing hemp fibers of different lengths and with varying proportions of mass (mass of gypsum to mass of fibers) into the gypsum matrix was investigated. The experimental data obtained indicate that adding hemp fibers to the gypsum matrix increases the static bending strength of the composites manufactured. The highest mechanical strength, at 4.19 N/mm2, was observed in fiber–gypsum composites with 4% hemp fiber content at 50 mm in length. A similar trend of increased strength was observed in longitudinal tension. Again, the composite variant with 4% fiber content within the gypsum matrix had the highest mechanical strength. Manufacturing fibers–gypsum composites with more than 4% hemp fiber content negatively affected the composites’ strength. Mixing long (50 mm) hemp fibers with the gypsum matrix is technologically problematic, but tests have shown a positive effect on the mechanical properties of the refined composites. The article indicates the length and quantity limitations of hemp fibers on the basis of which fiber–gypsum composites were produced.
Properties of Lightweight Insulating Boards Produced from Triticale Straw Particles
Insulating materials made from straw are becoming increasingly popular in the construction industry. Straw can be used in the construction of buildings as uncompressed straw chips or in the form of compressed panels. This study aimed to determine the possibility of manufacturing boards from straw particles with densities in the range of 150–400 kg/m3, allowing favorable mechanical properties while simultaneously providing high thermal and acoustic insulation properties. The study also analyzed the influence of the degree of carpentry density on the quality of the manufactured boards. The study shows that insulation boards can be produced from straw particles with satisfactory properties already at densities in the range of 200–150 kg/m3. Boards with this density have a compressive strength of 150 kPa, thermal resistance of 0.033–0.046 W/(m·K), and a sound absorption coefficient above 0.31.
The rate of change in the salaries of employees of the State Forests compared to selected sectors of the economy in Poland
Variations in Microstructural and Physicochemical Properties of Soy Wax/Soybean Oil-Derived Oleogels Using Soy Lecithin
Emerging natural-based polymers and materials progress and new technology innovations open the way for unique food products with high nutritional value development. In this regard, oleogel may be essential in replacing fatty acids from food products. In this study, we researched the effects of varied soy lecithin (SYL) concentrations on the various physicochemical characteristics of soy wax (SW)/refined soybean oil (RSO) oleogels. These oleogels had a soft texture. The microscopic analysis of the oleogels suggested that the thickness, length, and density of the wax crystals (needle-shaped) varied as the SYL content was changed. Colorimetric analysis indicated that the oleogels were slightly yellowish. FTIR spectrometry helped analyze the functional groups of the raw materials and the oleogels. All the functional groups present in the raw materials could be accounted for within the oleogels. The only exception is the hydrogen-bonding peak in SW, which was not seen in the FTIR spectrum of the oleogels. It was found that at a critical SYL content, the oleogel showed a stable and repeatable wax network structure. This can be described by the presence of the uniformly distributed fat crystal network in the sample. The DSC analysis revealed that the oleogel samples were thermo-reversible, with their melting and crystallization temperatures ~43 °C and ~22 °C, respectively. In gist, it can be concluded that the incorporation of SYL can impact the color, wax crystal network characteristics, thermal characteristics, and mechanical characteristics of the oleogels in a composition-dependent manner.
Fibre-Reinforced Polymers and Steel for the Reinforcement of Wooden Elements - Experimental and Numerical Analysis
These elements are innovative and of interest to many researchers for the reinforcement of wooden elements. For the reinforced beam elements, the effect of the reinforcement factor, FRP and steel elastic modulus or FRP and steel arrangement of the reinforcement on the performance of the flexural elements was determined, followed by reading the load-displacement diagram of the reinforced beam elements. The finite element model was then developed and verified with the experimental results, which was mainly related to the fact that the general theory took into account the typical tensile failure mode, which can be used to predict the flexural strength of reinforced timber beams. From the tests, it was determined that reinforced timber beam elements had relatively ductile flexural strengths up to brittle tension for unreinforced elements. As for the reinforcements of FRP, the highest increase in load-bearing capacity was for carbon mats at 52.47%, with a reinforcement grade of 0.43%, while the lowest was for glass mats at 16.62% with a reinforcement grade of 0.22%. Basalt bars achieved the highest stiffness, followed by glass mats. Taking into account all the reinforcements used, the highest stiffness was demonstrated by the tests of the effectiveness of the reinforcement using 3 mm thick steel plates. For this configuration with a reinforcement percentage of 10%, this increase in load capacity was 79.48% and stiffness was 31.08%. The difference between the experimental and numerical results was within 3.62–27.36%, respectively.
GL Beams Reinforced with Plywood in the Outer Layer
Glulam beams are increasingly used in the construction industry because of their high strength and the possibility of using round timber with smaller cross-sections. The load-bearing capacity of beams is strongly related to the quality of the outer layers and, in the case of wood, especially the tension zones. For these reasons, this study decided to replace the outer lamella with tensile plywood. The produced beams were subjected to static bending strength and modulus of elasticity evaluation. It was shown that the best static bending strength values were obtained for beams containing plywood in the tension layer. However, the change in structure in the tension zone of beams made of glued laminated timber results not only in an increase in the load capacity of elements produced in this way but also in a decrease in the range/range of the obtained results of bending strength. This way of modifying the construction of glued laminated beams allows a more rational use of available pine timber.
Heme iron as potential iron fortifier for food application – characterization by material techniques
Abstract The modern food industry requires new analytical methods for high-demand food supplements, personalized diets, or bioactive foods development. One of the main goals of the food industry is to discover new ways of food fortification. This applies to food products or supplements for human and animal diets. In our research, we focused on the solid particles of AproTHEM (dried porcine hemoglobin), which is approved for animal feeding and as a meat product additive, and AproFER 1000 (heme iron polypeptides), which is still being investigated. The study showed the possible application of advanced techniques for the examination of iron-based food additives. We evaluated selected techniques for particle size and morphology examination such as laser diffraction, optical microscopy, as well as scanning electron microscopy, and briefly discussed their usefulness compared with other techniques. On the basis of our results, we proposed a path of microscopic analysis for the study of material homogeneity. The structure of heme iron was evaluated by X-ray diffraction, FT-IR, and Raman spectroscopy supported with thermal behavior analysis (differential scanning calorimeter). Furthermore, a portable colorimeter was applied for L*a*b* color analysis. Our study proved that for new food product development, particle size analysis as well as typically used advanced materials techniques can be successfully applied.
Public Perception of the Use of Woody Biomass for Energy Purposes in the Evaluation of Content and Information Management on the Internet
The purpose of this study was to provide an overview of the public perception of the increase in forest biomass production, particularly in Poland, in the context of global and European Union (EU) climate and energy policy directions. Trends regarding the justification of biomass production in the EU and the world were also analyzed. The study compared the results of public sentiment surveys concerning the use of biomass in Poland as a member state of the European Union. The results are presented in tabular and graphical form. Data were obtained from analyses of social websites, study reports, and information social media in Poland. This study shows an increase in the negative perception of biomass use nationally and globally. It can be concluded that the increasing trend of forest biomass extraction resulted from the growing demand for green energy sources. Changes in European Union policy affected the popularization of biomass production worldwide as a result of growing energy demand. The use of renewable energy sources is necessary to reduce environmental degradation and secure society’s growing energy needs. It is necessary to increase the flow of information about the importance of forest biomass for the environmental aspects of society in order to gain acceptance of the EU’s promoted direction of stable renewable energy.
Development programming in the forest-based sector under economic uncertainty - the case of Poland during the pandemic and post-pandemic crisis
The study discussed the possibilities of reducing economic uncertainty under crisis conditions, as one perspective to eliminate the risk of business decisions. The solution was sought on the case of forestry-based sector in Poland, which was threatened by irregularity and permanent uncertainty. Stakeholders of the 'primary wood-based market', in the value chain: forestry - forestry services - woodworking industry, were invited to participate in a diagnostic survey, using the technique of individual in-depth interviews (IDI). The data, collected in 2020 and revised in 2024, was processed in the Analytic Hierarchy Process. Based on the AHP approach, the authors' research scenario was designed. As a result, an optimal leading anti-crisis strategy was selected, relevant to the ‘market of uncertainty’. An opportunity for the forest-based sector could be an anti-crisis co-opetition strategy, based on networking, integrating all market actors. Finally, practical recommendations for mesoeconomic sectoral policy in forestry were formulated.
Kiln-drying effectiveness as influenced by moisture content and density variation within a Scots pine timber batch
The Impact of Selected Market Factors on the Prices of Wood Industry By-Products in Poland in the Context of Climate Policy Changes
The objective of this study was to analyze price variability and the factors influencing the formation of monthly prices of by-products of the wood industry in Poland between October 2017 and January 2025. The analysis considered the impact of economic variables, including energy commodity prices (natural gas and coal) and industrial wood prices, on the pricing of wood industry by-products. The adopted approach enabled the identification of key determinants shaping the prices of these by-products. The effectiveness of two tree-based regression models—Random Forest (RF) and CatBoost (CB)—was compared in the analysis. Although RF offers greater interpretability and lower computational requirements, CB proved more effective in modeling dynamic, time-dependent phenomena. The results indicate that industrial wood prices exerted a weaker influence on by-product prices than natural gas prices, suggesting that the energy sector plays a leading role in shaping biomass prices. Coal prices had only a marginal impact on the biomass market, implying that changes in coal availability and pricing did not directly translate into changes in the prices of wood industry by-products. The growing role of renewable energy sources derived from natural gas and wood biomass is contributing to the emergence of a distinct market, increasingly independent of the traditional coal market. In Poland, due to limited access to alternative energy sources, biomass plays a critical role in the decarbonization of the energy sector.
The use of forest biomass for energy purposes in selected european countries
The utilization of primary and secondary woody biomass resources, despite controversies, is being promoted to reduce dependence on fossil fuels and due to the need to diversify energy sources and ensure energy security in European Union countries. Forest biomass is one of the renewable and sustainable energy sources that can be used for electricity, heat, and biofuel production. In the context of the ongoing energy crisis in Europe, an attempt was made to analyze the production and consumption of woody biomass for energy purposes (fuel wood, chips, and pellets). Specifically, an analysis of similarities between European countries in terms of biomass utilization was conducted. The analysis was complemented by a forecast of primary biomass production in selected European countries. The similarity analysis was conducted using the Ward method. Artificial neural networks (ANNs), including multi-layer feedforward perceptron (MLP) and radial basis function (RBF) models, were used to predict fuelwood extraction. The study showed that woody biomass remains an important source of bioenergy in Europe, and its significance as a strategic resource guaranteeing energy security is likely to increase. Fuel wood harvesting in Europe generally shows an upward trend, particularly in the Czech Republic, Germany, Estonia, Denmark, and the UK. A decreasing trend was observed in France, Spain, Greece, and Cyprus. The analysis revealed differences between countries in terms of woody biomass consumption. The ANN-based forecasts of fuelwood supply generally showed an increase in primary biomass harvesting.
The Energy Potential of Firewood and By-Products of Round Wood Processing—Economic and Technical Aspects
According to most energy demand forecasts, woody biomass has the potential to become an important source of renewable energy, especially during the transitional period of energy transition. The aim of this article was to estimate the energy potential of the biomass from the forest and the biomass generated by the mechanical processing of wood raw material and also to show the spectrum of possibilities for the potential use of the biomass for energy production in Poland. This research used available statistical and literature data on the species structure of harvested wood and the qualitative and assortment structures of woody biomass. The basic parameters of the raw material were evaluated in accordance with the EU classification of energy wood. This study confirmed the relationship between the energy potential of woody biomass and energy demand in Poland. The correlation coefficient for these variables was r = 0.984. This correlation was reflected in the significant shares of biomass in the production of electricity (more than 9%) or heat (almost 14%). Energy wood resources in Poland are smaller than in other European Union countries, which affects the scale of the potential use of woody biomass for energy purposes. Nevertheless, the use of such a biomass is fully justified from the point of view of possible development.
The Importance of Information Flow Relevant to Sustainable Forestry and the European Green Deal: The Case of Poland
The aim of the conducted research was to develop a classification of relevant/sustainable information by indicating the links between relevant information and the various functions of forests, and to obtain information on the value of specific sustainable forestry information for users of reporting information. The specific objectives include indicating the weight of information regarding sustainable development contained in the 2030 Forestry Strategy. The research was carried out using the example of the State Forests of Poland in correlation with the actions and initiatives of the European Green Deal, identifying the enduring functions of sustainable forestry, and attempting to relate them to the relevant information disclosed in mandatory reporting. The research problem was formulated as the question: which information disclosed in reporting, including statistical data, is considered by information users to be the most useful? The study was implemented through the development of survey questionnaires aimed at examining the information needs of information users. The study employed the triangulation method, in particular: a literature analysis and critique, a logical analysis and construction, and the snowball sampling method. Triangulation ensures the reliability of the research approach as well as the acquisition of comprehensive and contextual knowledge about the given phenomenon. The results of the empirical research indicated which pieces of information disclosed in the reporting on the activities of the State Forests are particularly useful for internal stakeholders and which do not necessarily provide value and therefore may be omitted in reporting. The study presented in the article constitutes the first empirical study of its kind in Poland, conducted in the context of understanding and defining relevant information from the perspective of sustainable forestry. The study illustrates individual behaviors in the context of the information currently disclosed in correlation with their usefulness.
Quality and Dimensional Parameters of Large-Sized Pine Timber in View of Expectations of Polish Sawmill Industry
Changes in the processing directions of round wood require the selection of raw material with appropriate quality and dimensional characteristics. In the case of large-size pine wood, these parameters translate significantly into its value and material indicators. The purpose of the research was to verify the currently applied classification principles with respect to the expectations of the market of wood industry customers. The research was conducted using the direct survey method, taking into account the structure of processing and sorting of production of wood industry representatives. The basic dimensional and quality groups for coniferous wood were separated, with wood defects assigned to them, in accordance with the currently binding principles of the quality and dimensional classification conducted by the State Forests. The respondents pointed out the necessity of changes in the minimum dimensions for wood of higher quality classes and changes in admissibility of selected defects in wood of lower classes.
Predicting Post-Production Biomass Prices
This paper presents the application of prediction in the analysis of market price volatility in Polish conditions of wood processing by-products in the form of biomass. The ARIMA model, which takes into account cyclical, seasonal, irregular fluctuations of historical data on the basis of which the forecast and long-term trends of selected wood products were made, was used in predicting prices. Comparisons were made between the ARIMA prediction method and the multiplicative Winters–Holt model. During the period studied (2017–2022), the changes in the market price of biomass were characterized by a wide spread of values. On average, the price of these products increased from 2017 to the end of 2022 by 125%. The price prediction analysis showed seasonal fluctuations in the case of wood chips. The uncertainty in price prediction is due to changes in supply resulting from the influence of global factors. The Diebold–Mariano test of matching accuracy confirms that the price prediction of the analyzed by-product sorts using the ARIMA and WH models is possible. The conclusion reached by comparing these two methods is that each can be used under certain market conditions of certain assortments. In the case of a stable wood product, the choice of the ARIMA model should be resolved, while in the case of price volatile products, WH will be a better choice. The difference between the predicted and actual price with ARIMA ranged from 2.4% to 11.6% and for WH from 3.7% to 29.8%.
Implications of Isomorphism in the Family of Apatite Compounds
Apatites are very important compounds of mineralogical and biological meaning. Apatites originated from the calcium hydroxy compound 3Ca3(PO4)2·Ca(OH)2 and potentially might form three series of isomorphic salts, derived from cationic substitutions in the positions of Ca(I) and Ca(II) ions in the core compound; anionic substitutions of phosphates; and substitutions of anions and very simple chemical entities instead of the hydroxyl group in channel locations. The energies coupled with the ion exchanges inside those three locations were studied using our original method resulting from the transformation of Braggs’ law. The energy changes resulting from the ion exchanges were studied in connection with either the ionic radii for the cations or ionic volumes for the anions. The same series were observed when the variabilities of energy were confronted with the variabilities in the sinus of diffraction angle Θ showing changes in momentum transfer. In particular, the relationships between the energy changes and the coupled changes in the universal crystallographic parameter d showed the surprising uniformity of all ion exchanges in the apatites. The incremental change in the Braggs’ d-parameter always demands the same change in the energy, with good approximation, independently of the location of the ion exchange. So, the isomorphism of the apatites is not triple but a uniform one at the energy level. Such an approach enables the estimation of the volume of the ion-□ (□-vacancies) agglomerates. The introduction of ions with greater volumes exerts the phenomenon of swelling of apatite cells, which can be quantitatively estimated. The dependence of diffraction spectra on the temperature allows for the determination of minimal values of crystallographic cell volumes and d parameters at the temperature of 0 K. In sum, the study of energies connected with the change of Bragg dimension d is a new and valuable method of insight into the behaviour of apatite crystals.
