Search Results (208)

Water deficit in the semi-arid region of Brazil is a critical limiting factor for tomato (Solanum lycopersicum Mill.), plant development and productivity. We evaluated whether foliar zinc (ZnO NPs) and iron (Fe₂O₃NPs) nano-oxides and their conventional salts (ZnSO₄·7H₂O and FeSO₄·7H₂O) mitigate water deficit effects on tomato (hybrid HM 2798). A split-plot field experiment was conducted with two irrigation levels (50% and 100% ETc) and five foliar treatments: control (no application), FeSO₄·7H₂O (T1), Fe₂O₃NPs (T2), ZnONPs (T3), ZnSO₄·7H₂O (T4), with four replications, totaling 40 experimental plots (2 irrigation levels × 5 foliar treatments × 4 replicates). The water deficit significantly reduced the leaf area index, photosynthetic rate, membrane stability, calcium and boron contents in fruits, and total and marketable yield. Foliar application of iron and zinc nano-oxides and their conventional sources had a limited effect on tomato plant growth but increased the photosynthetic rate under both irrigation levels. Under full irrigation, ZnSO₄·7H₂O increased total fruit production by 61% and fruit Zn content by 18.1%. In turn, Fe₂O₃ NPs (T2) led increases in fruit iron content by 117.3% under water deficit and 135.2% under full irrigation. Foliar application of Fe as Fe₂O₃ NPs is promising to promote the biofortification of tomato fruits with this micronutrient, especially in regions with deficiency problems of this micronutrient. Full article

Turn-milling is a relatively new process which combines turning and milling operations, offering a number of advantages such as chip breaking and interrupted cutting, which improves tool life. In addition to providing the capability of producing eccentric forms or shapes, it increases productivity for difficult-to-machine material at lower cost. This study investigates the influence of cutting speed and feed on surface roughness and tool wear in conventional turning and turn-milling of H13 tool steel. The tests were conducted for longitudinal and face machining strategies. It was found that the range of surface roughness in turning is lower than in turn-milling. In longitudinal turning, face-turning, and face turn-milling operations, surface roughness is elevated in the higher feeds. However, the surface roughness in longitudinal turn-milling operations can be reduced by increasing the feed. Although the simultaneous rotation of the tool and workpiece in turn-milling could negatively affect the surface quality, this operation provides the advantage of an interrupted cutting mechanism that produces discontinuous chips. Also, the wear of the endmill in longitudinal and face turn-milling operations is lower than the wear of the inserts used in conventional longitudinal and face turning. Using Response Surface Methodology (RSM), mathematical models were developed for surface roughness and tool wear in each operation. The RSM models developed in this study achieved coefficients of determination (R²) above 90%, with prediction errors below 7% for surface roughness and below 3% for tool wear. The analysis of variance (ANOVA) revealed that the feed and cutting speed are the most influential parameters on the surface roughness and tool wear, respectively, with p-value < 0.05. The experimental results demonstrated that tool wear in turn-milling was reduced by up to 50% compared to conventional turning. Full article

Surface pretreatment significantly influences the hygroscopic behavior of wood, which in turn affects surface stability when exposed to variable climatic conditions. This study focuses on how different surface pretreatment methods impact the performance of protective coating applied on spruce wood (Picea abies (L.) Karst.) during one year of natural weathering. Samples were prepared using various surface treatments: milling and sanding with grit sizes P40, P80, and P120, respectively. Two types of coatings were applied: a solventborne coating (ADLER Pullex Plus-Lasur) and a waterborne coating (DColor FK 47 UV Protect). The samples were exposed for 12 months at an outdoor testing site in Suchdol, Czech. Surface properties were assessed through color changes in the CIE Lab* space, gloss measurements (ISO 2813), contact angle analysis, and visual inspection. The results showed that exposure to UV radiation and microbial activities led to the gradual degradation of the optical properties and aesthetic appearance of the wood. Surfaces with greater roughness preserved their aesthetic properties more effectively, indicating a higher absorption of the coating. Untreated wood exhibited low water repellency, while the coated surface demonstrated enhanced hydrophobicity. Notably, the waterborne coating showed a temporary increase in contact angle around the sixth month, indicating surface clogging by dust particles. In contrast, the solventborne coating had a rapid decrease in wettability during the first nine months. These findings suggested the importance of surface pretreatment and coating type in maintaining the long-term performance and aesthetic appearance for wood used in exterior conditions. Full article

The need to diversify food products on the market, the interest of producer-farmers and food processors in nutritionally healthy raw materials, and especially the demand among consumers for new, high-quality product assortments have led to the introduction of ancient wheat species into cultivation. Ancient plant species are often grown using environmentally friendly agricultural technologies. The aim of the study was to compare the technological parameters, rheological properties of dough, and baking indicators of grains (and the flour milled from them) from ancient wheat species T. sphaerococcum and T. persicum with common wheat. These were cultivated using both traditional ploughing and simplified shallow tillage systems. The wheat grain was obtained from field experiments located in three certified organic farms in Poland. In the plant material samples, physical, technological and rheological parameters were determined. The grain, flour, baked bread, and the colour of grain and flour were characterised. It was found that the tested cultivation systems did not have a significant effect on the analysed traits (except for dough parameters: dough stability time, dough softening, and bread weight after removal from the oven and 24 h after baking where shallow tillage turned out to be more advantageous). In turn, the wheat species significantly influenced the tested traits. This factor was found to determine relatively high (higher than common wheat) values of protein complex and water absorption characteristics in ancient wheat flour (T. persicum: TPC/TPCF—156/150 g·kg⁻¹, WG/WGF—39.4/34.5%, WA—62.9%; T. sphaerococcum: TPC/TPCF—145/142 g·kg⁻¹, WG/WGF—38.5/33.3%, WA—58.2%). The obtained results for the technological and rheological properties of the grain and flour indicate that ancient wheat species, particularly T. persicum, can be a potential raw material for the production of healthy food, including bread baking. Full article

Ultrasonic-assisted machining (UAM) has emerged as a transformative technology for increasing material removal efficiency, improving surface quality and extending tool life in precision manufacturing. This review specifically focuses on the application of it to titanium aluminide (TiAl) alloys. These alloys are widely used in aerospace and automotive sectors due to their low density, high strength and poor machinability. This review covers various aspects of UAM, including ultrasonic vibration-assisted turning (UVAT), milling (UVAM) and grinding (UVAG), with emphasis on their influence on the machinability, tool wear behavior and surface integrity. It also highlights the limitations of single-energy field UAM, such as inconsistent energy transmission and tool fatigue, leading to the increasing demand for multi-field techniques. Therefore, the advanced machining strategies, i.e., ultrasonic plasma oxidation-assisted grinding (UPOAG), protective coating-assisted cutting, and dual-field ultrasonic integration (e.g., ultrasonic-magnetic or ultrasonic-laser machining), were discussed in terms of their potential to further improve TiAl alloys processing. In addition, the importance of predictive force models in optimizing UAM processes was also highlighted, emphasizing the role of analytical and AI-driven simulations for better process control. Overall, this review underscores the ongoing evolution of UAM as a cornerstone of high-efficiency and precision manufacturing, while providing a comprehensive outlook on its current applications and future potential in machining TiAl alloys. Full article

Copy number variation (CNV) is a common source of genomic structural variation by altering the number of DNA fragments, which in turn affects phenotypic variation and gene expression levels. However, there have been no reports of CNV in Chinese jujube (Ziziphus jujuba Mill.). In this study, we identified 16,570 CNVs from “Yuhong” × “Jiaocheng 5” and 140 hybrid progeny materials, of which 3607 CNVs were deletion type and 12,963 CNVs were duplication type. The distribution of CNVs in the Chinese jujube genome was systematically described, and the CNV genetic map of the whole genome level of the Chinese jujube hybrid offspring was constructed. Based on the field investigations, 13 individuals with severe black spot disease and no disease were analyzed for trait association. A total of 1837 CNVs were detected at the significant level of association, of which 1371 were duplication type and 466 were deletion type. And the GO (Gene Ontology) annotation item identified a systemic acquired resistance (SAR), and eight genes related to disease resistance were screened by the annotation. After validation by qPCR, these results further support the potential role in regulating black spot disease resistance. The constructed genome-wide CNV map of the hybrid progeny of Chinese jujube provides a new way of thinking for understanding the genetic basis of phenotypic variation of complex traits in Chinese jujube. Full article

The process of penetration of lubricants into the frictional interface in steel machining such as turning and milling is not well revealed, which has thus compromised their machining performance. In this paper, the penetration characteristics of deionized water (Di-water) containing different electro-osmosis additives were investigated using a steel-on-steel friction pair. The worn surface lubricated with water solutions were examined using advanced surface analysis techniques. The results indicate that water lubricants were electrically driven to the frictional interface for lubrication. The addition of positive electro-osmosis additives helped promote the penetration of water solutions, thus resulting in the formation of a thick lubricating film of iron oxide at the sliding surface. This reduced abrasion damage significantly, therefore producing a lower coefficient of friction (COF) and wear loss in comparison with pure water. Full article

In this work, a new approach to high-speed multi-coordinate milling was developed. The new approach is based on a new model of trochoidal machining; this is, in turn, based on the theoretical thickness of a chip and its ratio to the cutting edge’s radius, allowing us to establish the vibroacoustic indicators of cutting efficiency. The new model can be used for the real-time assessment of prevailing cutting mechanisms and chip formation. A set of new indicators and parameters for trochoidal high-speed milling (HSM), which can be used to calculate tool paths during technological preparation of slotting, was determined and verified. The size effect in the multi-coordinate HSM of slots on cast iron was identified based on the dependency of vibroacoustic signals on the cutting tooth’s geometry, HSM’a operational machining modes, theoretical chip thicknesses, the sizes of the cut chips, and the quality/roughness of the surface being machined. Based on the analysis of vibroacoustic signals, a set of the most important indicators for monitoring HSM and determining cutting and crack-formation mechanisms during chip deformation was derived. Based on the new model, recommendations for monitoring HSM and for assigning the tool path relative to the workpiece during production preparation were developed and validated. Full article

Cutting beech plywood using abrasive water jet (AWJ) technology represents a significant area of research due to increasing demands for precision, quality, and environmental sustainability in manufacturing processes within the woodworking industry. AWJ technology enables non-contact cutting of materials without causing thermal deformation or mechanical damage, which is crucial for preserving the structural integrity and mechanical properties of the plywood. This article investigates cutting beech plywood using technical methods using an abrasive water jet (AWJ) at 400 MPa pressure, with Australian garnet (80 MESH) as the abrasive material. It examines how abrasive mass flow rate, traverse speed, and material thickness affect AWJ lag, which in turn influences both cutting quality and accuracy. Measurements were conducted with power abrasive mass flow rates of 250, 350, and 450 g/min and traverse speeds of 0.2, 0.4, and 0.6 m/min. Results show that increasing the abrasive mass flow rate from 250 g/min to 350 g/min slightly decreased the AWJ cut width by 0.05 mm, while further increasing to 450 g/min caused a slight increase of 0.1 mm. Changes in traverse speed significantly influenced cut width; increasing the traverse speed from 0.2 m/min to 0.4 m/min widened the AWJ by 0.21 mm, while increasing it to 0.6 m/min caused a slight increase of 0.18 mm. For practical applications, it is recommended to use an abrasive mass flow rate of around 350 g/min combined with a traverse speed between 0.2 and 0.4 m/min when cutting beech plywood with AWJ. This balance minimizes jet lag and maintains high surface quality comparable to conventional milling. For thicker plywood, reducing the traverse speed closer to 0.2 m/min and slightly increasing the abrasive flow should ensure clean cuts without compromising surface integrity. Full article

Broader use of multioperational machines in forestry requires efficient methods for determining various timber parameters. Here, we present a novel approach to model the bark thickness (BT) as a function of stem diameter. Stem diameter (D) is any diameter measured along the bole, not a specific one. The following four regression models were tested: marginal model (MM; reference), classical nonlinear regression with independent residuals (M1), nonlinear regression with residuals correlated within a single tree (M2), and nonlinear regression with the correlation of residuals and random components, taking into account random changes between the trees (M3). Empirical data consisted of larch (Larix sp. Mill.) BT measurements carried out at two sites in northern Poland. Relative root square mean error (RMSE%) and adjusted R-squared (R2adj) served to compare the fitted models. Model fit was tested for each tree separately, and all trees were combined. Of the analysed models, M3 turned out to be the best fit for both the individual tree and all tree levels. The fit of the regression function M3 for SITE1 (50-year-old, pure stand located in northern Poland) was 87.44% (R2adj), and for SITE2 (63-year-old, pure stand situated in the north of Poland) it was 80.6%. Taking into account the values of RMSE%, at the individual tree level the M3 model fit at location SITE1 was closest to the MM, while at SITE2 it was better than the MM. For the most comprehensive regression model, M3, it was checked how the error of the bark thickness estimate varied with stem diameter at different heights (from the base of the trees to the top). In general, the model’s accuracy increased with greater tree height. Full article

Purslane (Portulaca oleracea L.) is a plant recognized as a valuable source of nutrients and bioactive compounds such as omega-3 fatty acids, antioxidants, vitamins, and minerals. This study investigates the effects of grinding techniques (knife, ball, and planetary ball mill) on the properties of purslane powder (surface microstructure, particle size distribution, and color), their influence on the phenolic content in the extracts of purslane powder before and after in vitro simulated digestion process, and the antioxidant activity of the purslane extracts. The results showed that applied grinding techniques affected the particle size distribution and surface morphology of the powder, which in turn influenced the gastrointestinal stability of the dominant phenolic compounds in purslane powder extracts. The powder obtained via ball milling, characterized by the highest proportion of fine particles (x < 100 µm), showed the highest content of total phenolics (656 mg GAE/L). Ball milling resulted in high preservation of the dominant phenolic acids in the powder extract after simulated gastric and intestinal digestion (83.55% and 69.42%) and high free radical scavenging activity (DPPH and ABTS) and ferric reducing power (FRAP). The results obtained emphasize the nutritional and biological benefits of purslane in the form of a fine powder. Full article

Digital twins, as part of Industry 4.0, are critical for advanced smart manufacturing processes, including machining. Sensor systems in smart manufacturing allow for real-time tracking of all changes in the machining process as well as simulation of an object’s behavior in the real world. It can also intervene and correct any defects that may arise during the machining process. The current review covers basic concepts for machining processes for the first time in detail, including Big Data, the Internet of Things, product lifecycle management, continuous acquisition and lifecycle support, machine learning, digital twin prototypes, digital twin instances, digital twin aggregates, and digital twin environments. The review article examines digital twins for the most common machining processes, such as turning, milling, drilling, and grinding. This review also highlights the benefits and drawbacks, as well as the prospects for using digital twins in smart manufacturing. Full article

This article looks at the ways in which satirical postcards provided political commentary at a pivotal moment in the Franco-Russian alliance. Often overlooked as a medium of communication, turn-of-the-20th-century postcards reflected contemporary cultural values and were an important art form. Here, the focus is on postcards created by Orens and Mille, two of the best caricaturists of the day, as their work offered scathing critiques of Russia’s constant need for financial assistance from its ally and point to the ways in which the public was growing weary of these demands. Closely examining some of their postcards shows how such sentiments were expressed in visual form while also revealing the power of ephemeral materials as historical sources. Full article

The production of fruit crops plays a vital role in the agricultural sector, contributing significantly to the social and economic development of rural communities. In Brazil, fruit production is diverse due to favorable edaphoclimatic conditions, with avocado (Persea americana Mill.) emerging as an important crop. Its production continues to expand in both cultivated areas and yield, making it a key export to non-producing countries. However, despite its importance, nutritional management information, crucial for achieving high yields, remains limited. Current guidelines on nutrition monitoring are outdated, general, and based on data from other countries with different edaphoclimatic conditions, making them not directly applicable to Brazilian orchards. Furthermore, outdated nutritional information becomes less reliable over time, as climate change alters soil conditions and crop nutrient concentrations and requirements, reinforcing the need for the establishment of up-to-date and specific nutritional information. This study aimed to establish nutritional standards for ‘Hass’ avocado production using the Diagnosis and Recommendation Integrated System (DRIS) and Compositional Nutrient Diagnosis (CND) methodologies, and to define sufficiency ranges (SRs) and Critical Levels (CLs) for both macronutrients (N, P, K, Ca, Mg, and S) and micronutrients (B, Cu, Fe, Mn, and Zn). The analyses were based on yield (t ha⁻¹) and leaf nutrient content data from commercial orchards, with datasets divided into younger (4–9 years) and older (10–26 years) plant groups. The DRIS effectively established nutritional standards for younger plants, explaining 11% of yield variation through nutritional balance. CND, in turn, was effective for both groups, accounting for 14% of yield variation and outperforming DRIS in associating nutritional status with productivity. SRs and CLs for ‘Hass’ avocado production were defined using both DRIS and CND. Together, these indices and diagnostic parameters offer valuable tools for enhancing nutritional monitoring and fertilization strategies in Brazil. Notably, SRs and CLs varied according to plant age. Full article

Investigating failure mechanisms in cutting tools used in advanced industries like biomedical and aerospace, which operate under extreme mechanical and chemical conditions, is essential to prevent failures, optimize performance, and minimize financial losses. The diamond-turning process, operating at micrometer-length scales, forms a tightly bonded built-up edge (BUE). The tribochemical interactions between a single-crystal diamond and its deformed chip induce inter-diffusion and contact, rapidly degrading the cutting edge upon BUE fracture. These effects intensify at higher deformation speeds, contributing to the observed rapid wear of diamond tools during d-shell-rich metal machining in industrial settings. In this study, these interactions were studied with niobium (Nb) as the transition metal. Tribochemical effects were observed at low deformation speeds (quasistatic; <1 mm/s), where thermal effects were negligible under in situ conditions inside the FEI /SEM vacuum chamber room. The configuration of the interface region of diamond and transition metals was characterized and analyzed using focused ion beam (FIB) milling and subsequently characterized through transmission electron microscopy (TEM). The corresponding inter-diffusion was examined by elucidating the phase evolution, element concentration profiles, and microstructure evolution via high-resolution TEM/Images equipped with an TEM/EDS system for elemental characterization. Full article