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This paper discusses the current status of the European research reactor (RR) fleet and identified opportunities for its utilization. The data for this analysis was collected through a specific questionnaire from which a database of the European RR fleet was created. The questionnaire was designed to assess the degree of exploitation of different RR applications and to identify gaps and opportunities for future utilization. The results indicate that the European RR fleet is older compared to the world average, with no new research reactors built in Europe since 1992. The majority of RRs reported low levels of exploitation across all applications, and a desire to expand utilization was expressed by 78% of respondents. Lack of manpower, finance, and customers were identified as the main obstacles preventing expansion, while the need for more nuclear engineers was identified as a clear opportunity to attract people to the field. The findings of this study emphasize the need for actions to be taken to combat future needs and to improve the utilization of the European RR fleet. Overall, this study provides valuable insights for policymakers, industry professionals, and researchers working in the field of nuclear energy.

Considering that commonly occurring mold fungi have the ability to develop very quickly on the surface of wood chips and the ongoing studies on finding the ways to use degraded wood, the conducted research was aimed at determining the physical and mechanical properties of chipboards containing various amounts (0%, 30%, 50%, and 70%) of pine chips inoculated with Aspergillus and Penicillium fungi, varying in a degree of infestation. The inoculation did not cause significant changes in the chemical composition of chips; however, it caused a decrease in the pH of their surface after nine-week incubation. While using them, lowered pH caused a deterioration in the mechanical characteristics of the boards and increased their thickness swelling and water absorption. Moreover, no changes in density, formaldehyde content and decomposition by brown-rot fungi were found. Overall, it was concluded that the addition of partially infested chips did not significantly affect any properties of the board; however, in the case of complete overgrowth, the amount of degraded chips should be less than 30%. [ABSTRACT FROM AUTHOR]

The application of commonly used flame retardants in most cases causes reduction in strength characteristic of particleboard. Therefore, it was decided to carry out research aimed at determining possibility of using pMDI-reinforced PF adhesive to produce board with increased fire resistance. The effect of different shares of particles impregnated with a mixture of potassium carbonate and urea on the particleboard properties such as density, density profile, bending strength, modulus of elasticity, internal bond and internal bond after boiling was investigated. Presented work also determined the effect of fire retardant on the performance of particleboards after ageing test and their reaction to fire. Studies demonstrated that PF adhesive modified with 20% pMDI is suitable for gluing impregnated wood particles. Regardless of their share, resultant panels showed no changes in strength and density. In the case of boards consisting of impregnated particles in the amount of 75% and 100%, lower values of swelling were demonstrated. The boards were classified as load-bearing boards for use in humid conditions. Fire retarding efficiency was confirmed by lowered mass loss, prolonged time needed to reach maximal burning rate, decreased gross calorific value and reduced ignitability when exposed to both radiant heat source and small flame source. [ABSTRACT FROM AUTHOR]

A significant amount of logging residue is produced during roundwood harvesting. Logs are often left in forest sites due to, for example, ecological or logistical aspects. Taking into account the fact that the number of studies focused on changes in the properties of the residue is very low, it was decided to conduct research on the effect of a three-year storage period in forest stands on the chemical properties and energy potential of the wood. The research design allowed for the determination of changes during up to three years of storage. The performed analysis showed a highly negative impact on the characteristics of the material. These adverse effects were probably caused by the activity of microorganisms such as fungi and bacteria, as evidenced by the increased concentrations of ergosterol and low-molecular-weight organic acids. Moreover, it was found that wood stored for three years was characterized by a lower cellulose content; an increased percentage of lignin; a reduced content of sterols (desmosterol, stigmasterol, lanosterol and β-sitosterol) and phenolic acids; and reduced antioxidant activity, as determined with the ABTS+ method. Storing logs also led to a reduction in the energy potential of the residues, as shown by a reduction in net and gross calorific value and an increased ash content. [ABSTRACT FROM AUTHOR]

The aim of the study was to investigate the effect of propylamine addition to urea-formaldehyde resin on the properties of resultant plywood. The research consisted in investigating the properties of both liquid and cured resins, as well as the produced plywood. Studies have shown that the incorporation of propylamine adversely affected reactivity of the adhesive mixtures by increasing their pH. The evaluation of adhesive chemical structure with FTIR spectroscopy showed some slight changes indicating the reaction of formaldehyde with introduced modifier. The addition of propylamine contributed to the considerable reduction of free formaldehyde contained in the cured adhesive. Furthermore, the propylamine was also found to work effectively as a formaldehyde scavenger by significantly reducing the hazardous emission from plywood. However, based on the results of bonding quality, delamination, bending strength and modulus of elasticity it was found that application of propylamine resulted in a noticeable deterioration of plywood properties. Therefore, the amount of introduced modifier should not exceed 1% of solid UF resin. [ABSTRACT FROM AUTHOR]

Despite many outdoors applications, the number of works aimed to determine the effect of changing conditions on the properties of glulam beams, in particular those produced in non-standard arrangements, is few. Therefore, the aim of this study was to assess changes in flexural strength properties (MOE, MOR) of the beams stored for 30 months in varying conditions. Analyzed variants of pine GLT beams included five-meter-long structural elements reinforced with oak timber, high-quality pine timber and steel rods stored both in the roofed shed outdoors and inside the climatic chamber. Moisture content of the beam varied significantly depending on the placement of the sensors (on the surface or inside the beam). The average modulus of elasticity after 30 months of storage decreased by approx. 7% compared to initial values. The results varied depending on both the assumed beam arrangement and the applied conditions. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the applicability of sugar beet pulp (SBP) in particleboard production as a substitute for wood material. Two variants of board density, 650 kg/m3 and 550 kg/m3, containing 0%, 25% and 50% of SPB, were evaluated. During the study the following features were measured: modulus of rupture (MOR), modulus of elasticity (MOE), thickness swelling (TS) and water absorption (WA). The results showed that boards containing up to 25% of SBP meet standards for boards for general-purpose used in dry conditions. Further increases in SBP content deteriorated some of the investigated properties of the boards. [ABSTRACT FROM AUTHOR]