This article presents the capabilities and selected measurement results from the newly developed low-cost air pollution measurement system mounted on an unmanned aerial vehicle (UAV). The system is designed and manufactured by the authors and is intended to facilitate, accelerate, and ensure the safety of operators when measuring air pollutants. It allows the creation of three-dimensional models and measurement visualizations, thanks to which it is possible to observe the location of leakage of substances and the direction of air pollution spread by various types of substances. Based on these models, it is possible to create area audits and strategies for the elimination of pollution sources. Thanks to the usage of a multi-socket microprocessor system, the combination of nine different air quality sensors can be installed in a very small device. The possibility of simultaneously measuring several different substances has been achieved at a very low cost for building the sensor unit: 70 EUR. The very small size of this device makes it easy and safe to mount it on a small drone (UAV). Because of this device, many harmful chemical compounds such as ammonia, hexane, benzene, carbon monoxide, and carbon dioxide, as well as flammable substances such as hydrogen and methane, can be detected. Additionally, a very important function is the ability to perform measurements of PM_2.5 and PM₁₀ suspended particulates. Thanks to the use of UAV, the measurement is carried out remotely by the operator, which allows us to avoid the direct exposure of humans to harmful factors. A big advantage is the quick measurement of large spaces, at different heights above the ground, in different weather conditions. Because of the three-dimensional positioning from GPS receiver, users can plot points and use colors reflecting a concentration of measured features to better visualize the air pollution. A human-friendly data output can be used to determine the mostly hazardous regions of the sampled area.

The main goal of the paper is to calculate the heat conductivity for three experimental hemp–lime composites used for structural construction purposes with the use of the experimental stand inside two compartments. Due to current construction trends, we are constantly searching for eco-friendly materials that have a low carbon footprint. This is the case of the analyzed material, and additional thermographic heat distribution inside the material during a fire resistance test proves that it is also a perfect insulation material, which could be applied in addition of popular isolating materials. This paper presents the results of certain hemp–lime composite studies and the potential for using hemp–lime composite for the structural construction industry. Hemp–lime composite heat transfer coefficient, fire resistance, and bulk density properties are compared to those of other commonly used construction materials. The obtained results show that the material together with supporting beams made of other biodegradable materials can be the perfect alternative for other commonly used construction materials.

The motivation for research to help address climate change is a continuous process of searching for eco-friendly materials in the building industry, which will allow minimizing the negative impact of this sector on the environment. The main objective of the paper is to assess the properties of a natural resource such as straw as an eco-friendly material in various variants for use in low-energy demand construction. The research results will fill the knowledge gap in the field of numerical analyses of the energy demand of straw material buildings based on the results of the conducted laboratory tests. A test of a heat transfer coefficient was conducted with different orientation of straw stalks. Then, samples were subject to a fire resistance test to determine material behavior at 1000 °C. During the fire resistance test, the clay-based plaster was ‘burnt out’, which hardened its structure, effectively preventing flames from reaching the insulation layers in the form of straw stalks. As a result of shrinkage (no plaster mesh), the plaster cracked and turned brick-red in color. The insulation layer of straw under the plaster was charred to a depth of 3.0 mm due to the high temperature. However, when the torch was turned off, no fire spread was observed in any layer of the sample. The 3D models of the buildings were created for different eco-friendly materials applied to make external walls. The results of numerical simulation allowed determining the amount of final energy needed to heat the designed building at the level of 26.38 (kWh/m²·year). Conclusions of the above-mentioned tests indicate very good thermal insulating properties determined using the lambda coefficient of 0.069 (W/m·K) and the possible application of straw bales as an alternative for conventional construction. Research has proven that it is possible to construct a building with low energy requirements using natural, easily available waste and completely biodegradable material.

The issues connected with the complex design of various facilities, including up-to-date boiler equipment as well as the ways of organizing the space around them, are the reasons why there is often a lack of room for mounting a flowmeter in accordance with the recommendations of manufacturers. In most cases the problem is associated with ensuring sufficient lengths of straight pipe leading into and out of a flowmeter. When this condition cannot be fulfilled, the uncertainty of measurement increases above the value guaranteed by the manufacturer of the flowmeter. This sort of operation problem has encouraged the authors of this paper to undertake research aimed at the analysis of applicability of averaging Pitot tubes in the areas of flow disturbance.

The paper presents the experimental fatigue test results for cyclic constant amplitude loading conditions for the case of the torsion of the PA4 (AW-6082-T6), PA6 (AW-2017A-T4) and PA7 (AW-2024-T3) aluminum alloy for a drilled diabolo type test specimen. The tests have been performed for the stress asymmetry ratios R = −1, R = −0.7, R = −0.5 and R = −0.3. The experimental results have been used in the process of a fatigue life estimation performed for a random generated narrowband stress signal with a zero and a non-zero global mean stress value. The calculations have been performed within the time domain with the use of the rainflow cycle counting method and the Palmgren−Miner damage hypothesis. The mean stress compensation has been performed with the S-N curve mean stress model proposed by Niesłony and Böhm. The model has been modified in terms of torsional loading conditions. In order to obtain an appropriate R = 0 ratio S-N curve fatigue strength amplitude, the Smith−Watson−Topper model was used and compared with literature fatigue strength amplitudes. The presented solution extends the use of the correction model in terms of the torsional loading condition in order to obtain new S-N curves for other R values on the basis of the R = −1 results. The work includes the computational results for new fatigue curves with and without the mean stress effect correction. The results of the computations show that the mean stress effect plays a major role in the fatigue life assessment of the tested aluminum alloys and that the method can be used to assess the fatigue life under random conditions.

This paper presents an analysis of methods to increase the efficiency of heat transfer in heat exchangers. The scope of the research included analysis of efficiency optimization using the example of two tubular heat exchanger structures most often used in industry. The obtained efficiency of heat recovery from the ground of the examined exchangers was over 90%, enabling the reduction of emissions of the heating systems of buildings. The paper presents the results of tests of two types of heat pipes using R134A, R404A, and R407C working agents. The paper also presents the results of experimental tests using the R410A working medium. The results included in the study will also enable the effective use of land as a heat store.