Since direct laser surface texturing of polymers is an emerging area, considerable attention is given to this technique with the aim of forming a basis for follow-up research that could open the way for potential technological ideas and optimization in novel applications. Laser pre-processing of ballistic textiles can raise surface roughness of smooth para-aramid fibres and as a result can improve the adhesion of functional coatings applied in following processing steps, thus opening new possibilities for material performance improvement. The impact resistance of ballistic fabric depends on the ability of its yarns in contact with the projectile absorb energy locally and disperse it to adjacent yarns without undergoing severe damage or failure. In addition to the yarn deformation and fracture, yarn resistance to pull-out contributes to the dissipation of impact energy significantly. The objective of this study is to optimize Kevlar^® KM2+ fabric surface topographies by adjusting the continuous wave (CW) CO₂ laser parameters in such a way that it increases the surface roughness and resistance to the yarn pull-out from the fabric without destroying the unique structure of the of Kevlar^® KM2+ fibres. Experimental research measured data show increase in surface roughness by 50–53% and set of laser parameter variants have been obtained that allow for an increase in KM2+ 440D woven fabric yarns pull out force from fabric in the range from 50% up to 99% compared to the untreated one.

As the world shifts towards more sustainable and eco-friendly practices, industrial hemp (Cannabis sativa L.) is gaining recognition as a versatile crop with numerous applications. The Baltic Sea region is well-suited for hemp cultivation, with its temperate climate and varied soil types. This study evaluates the suitability of various hemp varieties for the region, focusing on their ability to produce high-quality biomass, fibers, seeds, and dual-purpose products. The findings will contribute to the development of a thriving hemp industry in the region. Five years of research was conducted to investigate the productivity of 12 industrial hemp varieties, including 7 varieties mainly developed for seed production and 5 varieties mainly designed for fiber production. The results showed significant differences in yields among the varieties, with ‘Bialobrzeskie’ exhibiting the highest biomass yield (47.2 t ha⁻¹) and ‘Futura 75’ producing the highest fiber yield (10.8 t ha⁻¹). ‘Henola’ demonstrated the highest seed yield (3.5 t ha⁻¹), while ‘KA-2-2011’ and ‘USO-31’ were identified as dual-purpose varieties suitable for fiber (3.4 and 6.4 t ha⁻¹, respectively) and seed production (2.2 and 1.3 t ha⁻¹, respectively). The calorific value of hemp shives is comparable to wood fuels, indicating their potential as a viable fuel source. The results offer farmers a crucial tool for selecting the best-suited varieties for their specific region, promoting sustainable agriculture practices.

Marking of metal products is essential in many industrial processes. It is mandatory for the finished products according to regulations of the European and world legislation. Traditional marking usually creates contrasting symbols that can easily be erased and forged. In recent years, a new method for product identification has appeared - color marking. One of the advantages of this method is that it is difficult to counterfeit. This article aims to present the progress of color marking technology on two types of materials. Three groups of factors have been analyzed: the laser source; the technological process; material properties. Their role in obtaining a specific color marking on Ti and AISI 304 is shown. The results are presented in tables. Each color can be repeated only with strict observance of the three groups of factors.

So far, no significant modeling of reed biomass availability or assessment of the sustainability of reed products based on life cycle analysis has been conducted in Latvia. Nevertheless, these aspects are crucial for the development of reed-based products, as they help evaluate their market potential and overall socio-economic and environmental impact. This work aims to establish a methodology for modeling the extent of available reed distribution to forecast its future availability, as the availability of reed biomass is a vital prerequisite for utilizing this resource in the national economy. The novelty of this research lies in predicting reed areas based on existing historical data. The modeling is performed using GIS and satellite data.

Crop production is the most important crop production, since grain production contributes to the economic and political stability of any country, and the well-being of its citizens. The scientific paper summarizes information on the soil's chemical properties. Performed soil samples of the farm "Ratinieki" in the amount of soil, pH and electrical conductivity analysis of soil. On the basis of the research carried out, conclusions were made on the conditions of cereal cultivation on the holding.

Experiments were carried out on the process of color marking with a fiber laser on AISI 304 steel samples. The influence of the number of passes - one (at 0°), two (at 0° and 90°) and three (at 0°, 60° and 120°), the raster step and the scanning speed on the roughness and the resulting colors was studied. R/G/B coordinates of all marked squares were obtained. The positions of the individual colors in the color space were determined. Graphs of the dependence of the roughness on the raster step were constructed for three speeds and for the three types of passes. The obtained results were analyzed and summarized.