Piotr Szczyglak

Improving spray deposition within crop canopies is important for sustainable pesticide application, particularly when target surfaces are shielded or located in difficult-to-reach canopy zones. Air-assisted spraying may improve droplet transport and canopy penetration, but its effect is likely to depend on crop structure and target-zone position. This study evaluated the usefulness of air-assisted spraying in pea and parsley using a prototype sprayer operated with and without airflow support. Spray deposition was assessed with water-sensitive papers positioned at crop-relevant heights in horizontal and vertical orientations. In pea, air assistance significantly increased deposition on vertically exposed surfaces; for example, on the approach side at 50 cm above ground, mean coverage increased from 0.0622 to 0.4491% (+621.9%). Its effect on upper horizontal surfaces was limited. In parsley, the response was more selective: deposition increased on vertical surfaces at 20 cm, but decreased on horizontal ones, including a reduction at ground level from 0.0928 to 0.0393% (−57.7%). These results indicate that the performance of air-assisted spraying depends on crop architecture, target-zone accessibility, and surface orientation. Within the limits of this two-crop study, air assistance appears most justified where improved canopy penetration or reduced ground losses are particularly relevant. The observed deposition differences should not be interpreted as direct evidence of biological efficacy.

Efficient pesticide application remains a critical resource-management challenge in modern agriculture, where limited spray penetration reduces treatment efficacy, wastes chemical inputs, and increases environmental losses. This study quantified the effect of air-assisted spraying (AAS) on droplet deposition in two contrasting field crops, oilseed rape and wheat. Field trials were conducted using a sprayer equipped with an adjustable airflow module, and spray coverage was measured with water-sensitive papers at multiple canopy heights and orientations. In oilseed rape, AAS improved deposition on front-facing and top surfaces in the lower canopy, for example, increasing top-surface coverage at 90 cm from 53.4% to 65.5% at 6 km∙h⁻¹, indicating more uniform distribution and enhanced penetration. In wheat, which typically exhibits a more open canopy structure compared to oilseed rape, AAS effects were smaller and less consistent, with the greatest gain on front-facing lower surfaces (from 13.3% to 21.9% at 7 km∙h⁻¹). Although drift was not measured in this experiment, previous studies using the same sprayer prototype demonstrated measurable reductions, supporting the environmental relevance of improved deposition. These results highlight the role of canopy architecture in determining AAS performance and underscore the technology’s potential to reduce pesticide inputs, minimize off-target losses, and improve the resource efficiency of crop protection in line with EU Farm to Fork objectives.

Reducing pesticide drift is essential for minimizing environmental pollution and so implementing sustainable agricultural practices. Various methods can be employed to counteract this phenomenon, one of which is air-assisted spraying. This study evaluates the impact of air assistance on spray deposition using a field sprayer designed for cereal crops. Spray quality was assessed using water-sensitive paper, allowing drift levels to be estimated not only by assessing coverage but also by measuring the average number of droplets per square centimeter on the paper surface. This method provided a more reliable evaluation of drift reduction. The results indicate that air assistance reduced drift by 40.74% in coverage and 37.55% in droplet density per square centimeter. Notably, the greatest drift reduction occurred at the point of highest coverage—1 m from the spraying area—with an average reduction of 50%. Furthermore, at this distance, an 80% drift reduction was achieved at the recommended sprayer speed of 6 km/h. These findings highlight the potential of air-assisted spraying to enhance efficiency while reducing environmental impact. This research aligns with the objectives of the European Green Deal, supporting the transition toward more sustainable pesticide application techniques and contributing to environmentally responsible crop protection practices.

A problem has been noted regarding the admixture of fuel to a low viscosity lubricant in hybrid electric vehicles (HEVs). This is very detrimental to the wear and tear of engine operating components. In this study, the operating conditions of HEVs were analysed. Using X-ray fluorescence spectrometry (XRF), engine oils of two different viscosity classes were compared after the operating process and these data were compared with fresh reference samples. Attention was paid to the content of elements such as Ca, Zn, Mo, Sn, Cd, Fe Pb, Si, Cu, and Ni. The depletion of anti-wear additives, as well as the higher content of metallic wear products relative to the operated 5W30 (engine oil), contributed to the overall assessment of the lubricity of the 0W30 oil, as well as to the tribological results. Then, under laboratory conditions, oil samples contaminated with up to 1 to 8% fuel were subjected to rheological (mini AV-X viscometer) and tribological (four-ball tester) tests. The dependence of the local pressure at the metal-to-metal contact point in the kinematic node on viscosity showed the dissimilar nature of the used and fresh oil and the divergence of the domains for the two groups of samples. Increasing the fuel contamination of used oil above 4% drastically reduces the pressure responsible for maintaining the oil film. In order to improve lubricant performance during HEV operation in urban conditions, it was proposed to carry out extra-urban traffic driving in order to evaporate the fuel from the engine oil. A shorter oil change interval is also recommended.

The content of this article presents research on used and fresh engine oils. The aim of the experiment is to preliminarily develop a method for assessing the condition of engine oil subjected to service. A four-ball tester was used to compare the lubricating properties of the engine oil as one component of the tribosystem under laboratory conditions. The method used to determine the mashing load consisted of subjecting the kinematic node to a linearly increasing load with a build-up rate of 409 N·s-1 under operating conditions of approximately 20°C and a spindle speed of 500 rpm. The presented article is a continuation of the consideration of the lubricating properties of engine oils subjected to operation. The tests carried out made it possible to observe that fresh oils are characterised by their ability to carry higher loads in relation to oils subjected to service. This is evidenced by the obtained values of scuffing loads, which have a higher value for fresh oils (The average percentage increase in scuffing load for fresh oils was 62.23%). Comparing the friction torque characteristics with each other, it can be seen that the values of maximum friction torque are also higher for the fresh oils group. The modelling process made it possible to characterise changes in the tribological properties of the lubricating oil being used. In the future, the described model will be extended to include further input parameters (viscosity, contaminant content, fractional composition, etc.), which will allow a multi-parametric assessment of lubricating oil wear.

The article presents the results of tests, replaced according to the vehicle manufacturer's recommendations, of engine oils. The sample of engine oils in service came from spark-ignition and compression-ignition vehicles used in urban or mixed mode. During their collection, the type of drive unit, the mileage of the car and the number of kilometres the oil was used for were recorded for each sample (this was the main criterion for differentiating samples). In addition, a control group of samples consisting of fresh oils of the same viscosity grade and distributed by the same producer was set up to observe changes in the parameters of individual lubricants after the operating period. The first part of the empirical study consisted of determining the physico-chemical properties of the lubricants, i.e.: kinematic viscosity, density and water content. The second part involved anti-wear tests using a T-02U tribotester. The use of the tribotester made it possible to record the anti-wear parameter, i.e. moment of friction, and also the load imposed on the friction node, as a result of which it was possible to calculate the friction force and friction coefficient. The research was complemented by an analysis of worn surfaces of the friction node on a microscope. The tests carried out can be used for predictive purposes, in terms of assessing the condition of a lubricant subjected to an operating process in an internal combustion engine.

The wear of brake pads exposed to silica dust was measured. A novel test stand was developed to analysebrake pads' wear exposed to silica dust. Brake pad wear was determined by measuring pad lining geometryand mass changes. Geometric wear was analysed by determining changes in the thickness of the brake padlining during friction tests. In order to determine changes in mass, the brake pads were weighed before andafter the test. Brake pad wear was evaluated under dust-free conditions and under exposure to silica dust. Thetests revealed significant differences in brake pad wear under dust-free conditions and under exposure to silicadust. Mass loss of brake pad lining at different silica concentrations in airborne dust was described.

Because stricter norms of emission of hazardous substances are being introduced every few years, machinery manufacturers are also forced to introduce various modifications to reduce emissions. To this end, systems aimed at optimising the process of fuel combustion and reducing the amount of hazardous compounds are being applied. Three tractors used in agriculture, with various functional solutions, were examined in this study. The effect of various systems on reduction of hazardous emissions and fuel consumption was determined. The tests were conducted during the ploughing with a 4-bottom swivel plough. The effect of the selective reduction (SCR) system with AdBlue liquid, the exhaust gas recirculation (EGR) system, the particulate filter, the number of valves per cylinder and the type of a turbocharger in the engine’s inlet system were determined. It was observed during the tests that there were differences in fuel consumption and emissions depending on the constructional solutions applied in the tractors.

This study analyses issues concerning defects of passive paint coats. Four reasons of their occurrence have been identified: constructional, technological, operational, and caused by wear and tear. Standardized methods of paint coat assessment are discussed based on the impact of mechanical factors (PN-EN ISO 2409:2013-06, ASTM D3359-17, PN-EN ISO 1522:2008, PN-EN ISO 4624:2016-05, PN-EN ISO 1518-1:2011, PN-EN ISO 16276-2:2008, PN-EN ISO 6272:2011, PN-EN ISO 6860:2006, PN-EN ISO 2815:2004, PN-EN ISO 1519:2000). The original method of paint coat durability evaluation is presented with the consideration of synergetic impact of mechanical forces. This method permits carrying out testing in conditions close to those during normal service. The testing stand equipped with a rotating drum filled with mineral mass has been described as well as the optical method of assessing paint coat quality using original software developed by authors. Tests for three coating systems were carried out in order to present the possibilities of the developed method. In summary, the conclusions relating to the presented testing method are presented.