The paper is dedicated to the life prolongation of the tools designed for deep-hole drilling. Among available methods, an ion implantation process was used to improve the durability of tungsten carbide (WC)-Co guide pads. Nitrogen fluencies of 3 × 10¹⁷ cm⁻², 4 × 10¹⁷ cm⁻² and 5 × 10¹⁷ cm⁻² were applied, and scanning electron microscope (SEM) observations, energy dispersive spectroscopy (EDS) analyses, X-ray photoelectron spectroscopy (XPS) and Secondary Ion Mass Spectrometry (SIMS) measurements were performed for both nonimplanted and implanted tools. The durability tests of nonimplanted and the modified tools were performed in industrial conditions. The durability of implanted guide pads was above 2.5 times greater than nonimplanted ones in the best case, presumably due to the presence of a carbon-rich layer and extremely hard tungsten nitrides. The achieved effect may be attributed to the dissociation of tungsten carbide phase and to the lubrication effect. The latter was due to the presence of pure carbon layer with a thickness of a few dozen nanometers. Notably, this layer was formed at a temperature of 200 °C, much smaller than in previously reported research, which makes the findings even more valuable from economic and environmental perspectives.

This article presents a model of the geometry of teeth profiles based on the path of contact definition. The basic principles of the involute and convex–concave teeth profile generation are described. Due to the more difficult manufacturing of the convex–concave gear profile in comparison to the involute one, an application example was defined that suppressed this disadvantage, namely a planetary gearbox with plastic-injection-molded gears commonly used in vehicle back-view mirror positioners. The contact pressures and the slide ratios of the sun, planet, and ring gears with both teeth profile variants were observed and the differences between the calculated parameters are discussed.

An experiment was conducted to investigate into the effects of Ecklonia maxima extract (Kelpak SL) on yield, protein and ash contents of two bean cultivars. The study was carried out in 2012 - 2014 in Poland. During the growing season, 0.2% and 0.4% solutions of the bio-stimulant were applied by single and double spraying of plants against a control. The highest number and weight of grains were found when the plants of ‘Toska’ cultivar were single sprayed with 0.2% seaweed extract. Double spraying the plants with the 0.4% solution of Kelpak SL increased the number, its weight and the number of pods in cultivar ‘Aura’. The application of Kelpak SL increased protein content of grains in both bean cultivars. Higher the dose the double foliar application of the bio-stimulant, more was the ash content of the grain of plants of ‘Toska’ cultivar.

In this study, a novel rotary cleaning device was used for the separation and cleaning of wheat grains. This research analyzed the influence of the inclination angle of the sieve drum (K) of the device on the quality of these processes. In this article, the results obtained for four selected rotational speeds (n_b) of the sieve drum are presented. The quality of the separation and cleaning of the wheat grains was evaluated using three cleaning process parameters: coefficient of plump grain mass separation (W_z), coefficient of fine impurities separation (W_d), and total coefficient of cleaning effectiveness (E). Based on statistical analysis of the results, the inclination angle of the sieve drum had a significant effect on the quality of the wheat grain separation process. Coefficient W_z was highest for sieve drum inclination angles of K = 0° and K = 2.5°, whereas W_d was highest for K = -2.5°. The total coefficient of cleaning effectiveness (E) was characterized by different values for different inclination angles of the sieve drum. Keywords: Cleaning effectiveness, Conical sieve, Rotary cleaning device, Wheat grain cleaning.

Fabrication of alumina–tungsten carbide nanocomposite was investigated. Characteristics of the densification and sintering were analyzed considering both the nano-size particle starting powders and the processing stages. Different heating rates were generated during densification and consolidation with a maximal load was applied only after a temperature of 1000 °C was reached. Due to the varying dominance of different physical processes affecting the grains, appropriate heating rates and pressure at different stages ensured that a structure with submicron grains was obtained. With directly applied alternating current, it was found that the proportion Al₂O₃ (50 wt.%)–WC provided the highest fracture toughness, and a sintering temperature above 1600 °C was found to be disadvantageous. High heating rates and a short sintering time enabled the process to be completed in 12 min, saving energy and time.

The quality of pasta can be evaluated by measuring the characteristics which encompass the most important quality parameters, such as colour, cooking properties and texture. The aim of the study was to suggest new indices which can be used to evaluate the quality of pasta. For the tests, 15 samples of spaghetti (produced from either semolina or common wheat flour) were used. The bending test was performed for the determination of the strength properties of raw pasta, while the pasta colour parameters were evaluated via the Commission Internationale de l’Eclairage system. The pasta cooking test included the evaluation of optimum cooking time, weight increase index and cooking loss. The samples of cooked spaghetti were cut, and the parameters describing pasta texture were determined. Statistical analysis showed significant correlations (α = 0.05) between colour parameters (lightness and redness) and pasta ash content (R = -0.90 and 0.84, respectively). The mechanical properties of raw pasta correlated positively with pasta density. The strongest correlation was found between pasta density and flexural strength. The destruction force for raw spaghetti during the bending test correlated significantly and positively with the cutting force of the cooked pasta. The obtained correlations can be helpful in pasta quality evaluation.