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A low-carbon micro-alloyed (LCMA) steel with a body-centered cubic (bcc) crystal structure suitable for extremely low temperatures was developed by overcoming the intrinsic ductile-to-brittle transition in bcc alloys at cryogenic temperatures. The excellent cryogenic-to-ambient impact toughness in the LCMA rolled plate results from its heterogeneous microstructure, which gradually changes from bamboo-like ultrafine grains (∼ 1.1 μm) on the surface to relatively equiaxed coarse grains in the core (∼ 3.4 μm), accompanied by a distinct texture gradient variation. The heterostructured LCMA steel displays a cryogenic impact toughness of ∼200 J/cm2 at 77 K, which is 24 times higher than the coarse-grained LCMA steel. Such high impact toughness of heterostructured LCMA arises from the coordinated deformation mechanisms over different length-scales coupled with delamination toughening. At 77 K, the heterostructured steel plate deforms by forming cellular sub-structures at the core to the surface, which refines the microstructure and promotes hetero-deformation induced (HDI) hardening to improve intrinsic toughening. Moreover, the subsequent delamination process induces extrinsic toughening by shielding and blunting the cracks, with the local plane-stress conditions induced by delamination promoting ductile fracture of the coarse grains in the core regions. This low alloy steel with its heterogeneous microstructure exhibits extraordinary impact toughness at cryogenic temperatures highlights the possibility of materials design strategies for sustainable development.

Heterogeneous metallic structures constitute a novel class of materials with excellent mechanical properties. However, the existing process for obtaining heterostructures from a single material does not meet large-scale industrial requirements. In this study, a pure copper heterostructured laminate (HSL) composed of a surface elongated-grain layer and a central equiaxed-grain layer was fabricated by rolling bonding and annealing. To study the effect of the interface on the mechanical properties of gradient-structured materials, both laminate metal composite (LMC) and non-composite laminate (NCL) were fabricated by cold-rolling pretreatment of the center layer (60% reduction) and cold-rolling bonding of the whole blank (67% reduction). Then, the HSL was obtained by controlling the post-annealing regimes, the microstructure of each layer was optimized, and a larger degree of microstructural heterogeneities, such as grain size, misorientation angle, and grain orientation, was obtained, which resulted in obvious mechanical differences. Tensile tests of the HSL, surface layer, center layer, and NCL specimens revealed that the HSL annealed at 300 °C for 1 h had a significantly higher strength than the center layer and a higher elongation than the surface layer. The HSL had a tensile strength and elongation at fracture of 278.08 MPa and 46.2%, respectively, indicating a good balance of strength and plasticity. The improved properties were primarily attributed to the strengthening or strain hardening due to the inhomogeneous deformation of the heterogeneous layers in the laminate and the mutual constraint acquired by the distinct layers with strong mechanical differences. The HSL had an interfacial bonding strength of 178.5 MPa, which played a vital role in the coordinated deformation of the heterogeneous layers. This study proposes an HSL design method that effectively simplifies the process of obtaining heterostructures in homogeneous materials by controlling the cumulative deformation of the surface and center layers. [ABSTRACT FROM AUTHOR]

The causes of the formation of bumps on metallographic specimens of sheets and strips subject to inspection are established by analyzing the components of Kovar alloy (trademarked name of Fe29%Ni18%Co precision alloy; named 29NK-VI in Russia) and identifying possible deviations from its manufacturing process, starting from the preparation of the initial melt. It was found out that the formation of bumps is a manifestation of leading diffusion of some alloy components into others, mainly cobalt into nickel. Such a phenomenon may occur in case of significant chemical inhomogeneity of the metallic material caused by the segregation of the components of its initial melt according to their magnetic susceptibility and the refusal to homogenize the resulting ingot. It is argued that bumps on specimens should be considered as a rejection criterion for a material intended for the manufacture of precision parts of vacuum electronic devices, as they are indicative of its unbalanced composition. The residual diffusion phenomena contribute to the change in the phase state of the material, followed by embrittlement, change in precise dimensions, and loss of vacuum in parts of vacuum electronic devices. It is assumed that residual diffusion is one of the causes of the γ→α phase transformation in Kovar at low temperatures. [ABSTRACT FROM AUTHOR]

Managing the metal's texture throughout the entire processing procedure is imperative for controlling the final properties of metal alloys. In the aerospace industry, α‐Ti alloys have been successfully utilized in applications such as aircraft skins, heat shields, and heat exchangers. However, inherent mechanical strength, fatigue sensitivity, and fracture toughness limitations have significantly restricted their wider adoption. On the other hand, β‐Ti alloys have received increasing attention in the biomedical field due to their lower elastic modulus. However, their actual application has been primarily restricted by the inability to match natural bone's Young's modulus sufficiently. Among these application limitations for both α‐Ti and β‐Ti alloys, texture is an essential factor affecting mechanical properties. Elucidating texture evolution on α‐Ti and β‐Ti alloys is crucial for enabling the expansion of their applications. This review summarizes detailed analyses of the intertwined evolution of texture and microstructure in α‐Ti and β‐Ti alloys during cold rolling, hot rolling, and annealing. Furthermore, based on these fundamental materials science insights, the resultant impact of texture and microstructure on achieving targeted mechanical properties is discussed. Finally, potential pathways are proposed to further guide texture and microstructure evolution in α‐Ti and β‐Ti alloys to meet application requirements. [ABSTRACT FROM AUTHOR]

Hospital functionality relies not only on the building's structural robustness but also on the seismic performance of its Nonstructural elements, Systems, and Contents (NSC). The objective of this study is to characterize the earthquake‐induced damage to the medical equipment deployed in the full‐scale, five‐story concrete building tested at the University of California, San Diego (UCSD) in 2012 when subjected to Design (DE) and Maximum Considered Earthquake (MCE) levels of demand with Fixed‐to‐the‐Base (FB) support condition. The experimental equipment displacement responses are extracted using the Camera Projection Technique (CPT). Then, sophisticated rolling and sliding models, including instantaneous motion tracking and impact detection are developed to reproduce the equipment behavior obtained from CPT. It was found that CPT was capable of extracting the observed responses and identifying impacts despite the severity of the shaking as long as no significant uplift of the equipment occurred. In addition, both numerical models were capable of reproducing the equipment's displacement trajectories, rotations about the vertical axis (yaw), and impacts as long as no interlocking of the equipment's parts occurred. Moreover, a case study of a partially equipped Emergency Room (ER) was set up to demonstrate that even for low‐intensity motions, the damage to equipment may be significant. Finally, the impact acceleration (a⃗imp$\vec{a}_{imp}$) is proposed as a proxy indicator of damage to medical equipment; however, more functionality tests accompanied by detailed pre‐ and post‐inspections are needed to define robust damage limit states and performance objectives for medical equipment. [ABSTRACT FROM AUTHOR]

The present work constitutes a generalization of the hydrodynamic model used to predict the pressures and the rolling speeds during the hot rolling of aluminum and copper strips. The hydrodynamic model with a linear behavior (Newton viscous) of the materials shows good predictions in the literature but its applicability is questionable in non-linear cases, when the materials exhibit viscoplastic or plastic behavior. This work extends the model to accommodate non-linear cases commonly encountered in rolling models (viscoplastic and plastic behaviors). The obtained results are in good agreement with experimental data from the literature. The validated model can, therefore, be considered an enhanced hydrodynamic model for predicting pressures and velocities during both hot and cold rolling of thin strips. [ABSTRACT FROM AUTHOR]

Although low mechanical properties, Zinc (Zn) alloy systems with Copper (Cu) and Silver (Ag) as alloying elements have strong biocompatibility and biodegradability characteristics. This study examined the effects of rolling parameters and Ag alloying on the mechanical, biodegradable, and final structure of an alloy based on Zn. Comparing treated and untreated specimens, the addition of Ag led to a considerable improvement in both hardness and compressive strength. The produced alloys with varying amounts of Ag (between 1 and 4 wt%) were cold rolled at 400–800 r/min and friction coefficients between 0.3 and 0.5. The alloys' ultimate strength rose with an increase in rolling speed for Zn1Cu4Ag, and hardness and compressive strengths rose to 80HV and 470 MPa, respectively. It was demonstrated that rolling force rose somewhat with Ag concentration but significantly increased with rolling speed and friction. E. Coli and S. aureus were used to assess the biodegradable alloys' antibacterial properties. For the Zn-1Cu-2Ag alloy, the inclusion of Ag resulted in a considerable (50%) rise in antibacterial activity that exceeded the effects seen in other alloy systems. [ABSTRACT FROM AUTHOR]

The results of the investigation into heat-transfer enhancement at increasing critical heat flux due to modification of a wall's inner surface are presented. The greater need for new, compact, and energy-efficient heat exchangers on the basis of minichannels for high-tech industries makes this investigation urgent. The potential for application of small diameter channels in systems where various dielectric liquids or freons at moderate and high reduced pressures can be used as a coolant is being actively investigated today. The experiments were performed in a heated vertical minichannel. The wall was modified by the rolling method, which has not yet been used in small diameter channels. The experiments were performed with a forced flow of R125 refrigerant at high reduced pressures of 0.43 and 0.56 in the range of mass flowrates from 200 to 1200 kg/(m2 s), which is the most applicable range for minichannel heat exchangers. Heat transfer during forced convection and flow boiling was studied. The experimental setup and the minichannel inner wall modification method are described. Experimental data on forced convection and flow boiling heat-transfer coefficients, critical heat fluxes, and pressure drops are presented. The heat-transfer data were compared with the results obtained previously with the inner surface modified by the action of laser pulses on the outer wall. The convective heat-transfer coefficient in a minichannel with the inner surface modified by rolling was found to be much greater than that in a smooth channel. The obtained convective heat-transfer coefficients are compared with the predictions by empirical formulas derived for large-diameter pipes with the wall surface modified by rolling. [ABSTRACT FROM AUTHOR]

The 7046 aluminum alloy possesses a favorable fatigue property, corrosion resistance and weldability, but its moderate strength and plasticity limit its wider application and development. In the present study, severe plastic deformation (SPD) was applied prior to T6 treatment to significantly enhance the strength and toughness of the 7046 aluminum alloy. The results show that the alloy processed by four passes of equal channel angular pressing (ECAP) at 300 °C prior to T6 treatment exhibits an excellent mechanical performance, achieving an ultimate tensile strength (UTS) and elongation (EL) of 485 MPa and 19%, respectively, which are 18.6% and 375% higher than that of the T6 alloy. The mechanical properties of the alloy are further improved by an additional room temperature (RT) rolling process, resulting in a UTS of 508 MPa and EL of 23.4%, respectively. The increased presence of η′ and Al6Mn phases in the 300°C4P-R80%-T6 and 300°C4P-T6 alloys contributes to a strengthening and toughening enhancement in the SPD-processed T6 alloy. The findings from this work may shed new insights into enhancing the 7046 aluminum alloy. [ABSTRACT FROM AUTHOR]

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In order to develop the aluminum sheets suitable for the twin-belt continuous casting and direct rolling, the composition optimization of Al-Mg-Mn alloys evolved from AA5052 (Al-2.5 Mg) alloy was firstly carried out via the synergy between the PANDAT software and the micro–hardness test. Subsequently, the influence of Er and Zr on the microstructure and mechanical properties of the optimized Al-Mg-Mn sheet (Al-1.5 Mg-0.8Mn) was investigated in this work. The results showed that the tensile properties of Al-1.5 Mg-0.8Mn sheets processed by the rolling and the subsequent annealing were improved by the co-addition of the Zr and Er. The optimized tensile properties (UTS: 320.5 MPa; YS: 231.6 MPa; E.L.: 6.75%) were achieved in Al-1.5 Mg-0.8Mn sheets modified by 0.2 wt.% Zr and 0.3 wt.% Er, which is attributed to the finest fibrous grains, the fine, homogeneously distributed residual Al6Mn, Al3Zr and Al3(Zr, Er) second phases and more nano-sized Al3(Zr, Er) precipitations. [ABSTRACT FROM AUTHOR]

In present study, the texture evolution during cold rolling and subsequent annealing of a Fe-24Cr-22Ni-7Mo super austenitic stainless steel was investigated, and new insights into the mechanisms of texture evolution were obtained. The results show that macrotexture evolution during cold rolling can be categorized into two stages. Below 33.3% cold reduction, the material form strong Goss, Copper, and S texture component due to dislocation plane slipping. Above 33.3% reduction, strong Brass, Goss, and Copper-Twin texture components are formed, accompanied by a decrease in Copper and S component content. Moreover, when the cold reduction reaches 66.6%, the strength of the γ-fibre texture suddenly increases. This increase is attributed to the rotation of the Copper-oriented grains and the Copper-Twin-oriented grains in the lamellar twin region to {111} and {111} along < 011>//TD direction, respectively. It is significant to note that twinning plays a dominant role in the formation of the Brass-type texture in the super austenitic stainless steel at large deformation. Additionally, the annealing of cold deformed materials results in the formation of random and scattered recrystallization texture. This may be due to the small difference in deformation energy storage of grains with different orientations after austenite deformation. [ABSTRACT FROM AUTHOR]

Rolling plays an important role in shaping the characteristic quality of black tea. However, the dynamic alterations in volatile compounds during the rolling process remain unclear, which hampers the quality control of black tea. In this study, the dynamic changes of volatile compounds in Congou black tea throughout the rolling process were explored by a combination of GC-E-Nose and GC-MS analysis. The results of PCA and PLS-DA by GC-E-Nose revealed significant alterations in the volatile profiles, particularly at the 15-min rolling stage. A total of 82 volatile compounds including eight categories were identified in Congou black tea during the rolling process. The most abundant volatiles were aldehydes, alcohols, and esters. Through the integration of variable importance in the projection >1 and p < 0.05, 21 volatile compounds were pinpointed as pivotal volatiles responsible for distinguishing diverse rolling processes. According to their pathways, glycoside-derived volatiles (GDVs) (such as linalool and geraniol) and fatty acid-derived volatiles (FADVs) (such as (Z)-2-hexen-1-ol and hexanal) highlighted the pivotal role in the formation of the aroma of black tea during rolling process. GDVs, characterized by floral, honeyed, and fruity aromas, reached the lowest point at 35-min rolling and subsequently rebounded. FADVs exhibited an ascending trajectory during the initial 15-min rolling, followed by a downward trend. These findings provide invaluable insights into the aroma evolution during the rolling stage, offering strategies for enhancing the aroma quality of Congou black tea. [ABSTRACT FROM AUTHOR]

Recent losses in the abundance and diversity of arthropods have been documented in many regions and ecosystems. In grasslands, such insect declines are largely attributed to land use, including modern machinery and mowing regimes. However, the effects of different mowing techniques on arthropods remain poorly understood. Using 11 years of data from 111 agricultural grassland plots across Germany, we analyzed the influence of various grassland management variables on the abundance and abundance‐accounted species richness of four arthropod orders: Araneae, Coleoptera, Hemiptera, and Orthoptera. The analysis focused on detailed mowing information, for example, days after mowing and mower type, and compared their effect with other aspects of grassland management, that is, rolling, leveling, fertilization, and grazing. We found strong negative effects of mowing on all four arthropod orders, with arthropod abundance being lowest directly after mowing and steadily increasing to three to seven times the abundance after 100 days post‐mowing. Likewise, Hemiptera and Coleoptera species richness was 30% higher 100 days after mowing. Mower width showed a positive effect on Orthoptera abundance, but not on the other arthropods. Arthropod abundance and Coleoptera species richness were lowest when a mulcher was used compared to rotary or bar mowers. In addition to mowing, intensive grazing negatively affected Orthoptera abundance but not the other orders. Mowing represents a highly disturbing and iterative stressor with negative effects on arthropod abundance and diversity, likely contributed by mowing‐induced mortality and habitat alteration. While modifications of mowing techniques such as mower type or mowing height and width may help to reduce the negative impact of mowing on arthropods, our results show that mowing itself has the most substantial negative effect. Based on our results, we suggest that reduced mowing frequency, omission of mowing in parts of the grassland (refuges), or extensive grazing instead of mowing have the greatest potential to promote arthropod populations. [ABSTRACT FROM AUTHOR]

Abstract Heterogeneous metallic structures constitute a novel class of materials with excellent mechanical properties. However, the existing process for obtaining heterostructures from a single material does not meet large-scale industrial requirements. In this study, a pure copper heterostructured laminate (HSL) composed of a surface elongated-grain layer and a central equiaxed-grain layer was fabricated by rolling bonding and annealing. To study the effect of the interface on the mechanical properties of gradient-structured materials, both laminate metal composite (LMC) and non-composite laminate (NCL) were fabricated by cold-rolling pretreatment of the center layer (60% reduction) and cold-rolling bonding of the whole blank (67% reduction). Then, the HSL was obtained by controlling the post-annealing regimes, the microstructure of each layer was optimized, and a larger degree of microstructural heterogeneities, such as grain size, misorientation angle, and grain orientation, was obtained, which resulted in obvious mechanical differences. Tensile tests of the HSL, surface layer, center layer, and NCL specimens revealed that the HSL annealed at 300 °C for 1 h had a significantly higher strength than the center layer and a higher elongation than the surface layer. The HSL had a tensile strength and elongation at fracture of 278.08 MPa and 46.2%, respectively, indicating a good balance of strength and plasticity. The improved properties were primarily attributed to the strengthening or strain hardening due to the inhomogeneous deformation of the heterogeneous layers in the laminate and the mutual constraint acquired by the distinct layers with strong mechanical differences. The HSL had an interfacial bonding strength of 178.5 MPa, which played a vital role in the coordinated deformation of the heterogeneous layers. This study proposes an HSL design method that effectively simplifies the process of obtaining heterostructures in homogeneous materials by controlling the cumulative deformation of the surface and center layers.

This work investigated the effect of rolling temperature (25–800 °C) on rolling-texture development and sheet formability of pure Ti. The rolling temperature significantly affected the development of the typical transverse-direction (TD)-split basal texture in pure Ti sheet by altering the tilting angle of (0001) basal poles. Notably, a normal-direction (ND) basal texture, where the tilting angle of (0001) basal poles was approximately 0°, developed at an intermediate rolling temperature of 400 °C. This result is remarkable because the ND basal texture is rare in pure Ti. Formation of this unusual ND basal texture was attributed to significant activation of basal slip. In contrast, a typical TD-split basal texture was dominant at the other rolling temperatures. Formation of this typical texture was attributed to pyramidal slip. After subsequent recrystallization annealing, sheet formability was examined. Despite their different textures, the sheets previously rolled at the different rolling temperatures showed similar formability. This similarity occurred because any given texture could not simultaneously provide in-plane stretching uniformity and thinning capability during sheet forming. The present study suggests an important guidance for modifying texture of pure Ti sheets to effectively increase their formability.

Minimizing geometric error in the bending of large sheets remains a challenging endeavor in the industrial environment. This specific industrial operation is characterized by protracted cycles and limited batch sizes. Coupled with extended cycle times, the process involves a diverse range of dimensions and materials. Given these operational complexities, conducting practical experimentation for data extraction and control of industrial process parameters proves to be unfeasible. To gain insights into the process, finite element models serve as invaluable tools for simulating industrial processes for reducing experimental cost. Consequently, the primary objective of this research endeavor is to develop an intelligent finite element model capable of providing operators with pertinent information regarding the optimal range of key parameters to mitigate geometric error in the bending of large sheets. This prediction model is based on response surface method to predict the bending diameter of the pipe taking into account three main process parameters: the plate thickness, the length, and the roll displacement. These results present promising prospects for the automation of the industrial process because the average geometric error in curvature is recorded at 0.97%, thereby meeting the stringent industrial requirement for achieving such bending with minimal equivalent plastic deformation. [ABSTRACT FROM AUTHOR]

Automobiles are the inevitable mode of transportation. However, increasing fuel prices and carbon dioxide emissions are posing a serious threat to automobile users and the environment. Thus, the development of new lightweight materials has been a key area of research. Magnesium-based commercial alloys (AZ and ZK series alloys) are the lightest among all structural metals. However, there is still a question about the replacement of Aluminum-based alloys due to HCP crystal structure. In this connection, MgAlCaMn (AXM) Mg alloy can be a choice as an alternative to the existing Mg-based commercial alloys for structural applications. It contains (Al, Mg)2Ca, Al2Ca, Mg2Ca, and Al8Mn5 as the secondary phases, contributing to the microstructural refinement and property enhancement. However, the formation of those precipitates depends on the amount of Al, Ca, and Mn, especially, the Ca/Al ratio. In addition, the secondary processes influence the grain refinement and property enhancement of texture modifications. Hence, this review article focuses on elaborating on the significance of the Ca/Al ratio for the precipitate formation, secondary process, and texture modifications. The co-segregation behavior of other micro-alloying elements like Cerium, Lanthanum, and Zinc in AXM Mg alloy systems has also been discussed for property enhancement.

In an industrial context, selecting an appropriate crystal plasticity (CP) model that balances efficiency and accuracy when modelling deformation texture (DT) is crucial. This study compared DTs in IF-steel after undergoing cold rolling reductions using different CP models for two input texture scenarios. Three mean-field (MFCP) models were utilised in their most basic configurations, without considering grain fragmentation or strain hardening, in addition to a dislocation-density-based full-field (FFCP) model. The study quantitatively compared the results from the MFCP models with those from the FFCP models. Furthermore, all CP model results were compared with experimental textures obtained from electron back-scatter diffraction (EBSD) experiments. The findings revealed that certain MFCP models could predict deformation textures as accurately as the FFCP models. Notably, one of the MFCP models exhibited a superior match with experimental textures for cold rolling reductions at 60%. Upon closer examination of specific crystallographic components, it was observed that MFCP models tended to predict a stronger {111}〈211〉 component, while the full-field model favours the {111}〈011〉 component. It is crucial to emphasise the importance of quantifying the texture within individual grains when assessing the macro-level deformation texture in rolling simulations.

The object of research is the process of granulation of mineral fertilizers by applying rolling and pouring methods, as well as in fluidized and suspended layers with active hydrodynamics of flows. It is noted that the development of the main technological stages of the production of granulated fertilizers should be aimed at improving the hardware design of granulators, establishing the most rational regime and technological parameters of the process in order to increase its efficiency and reduce energy costs. It is noted that the main indicators of the efficiency of granulation plants using heat are economic costs, exergy losses, as well as reduced costs. The method of exergy analysis for the assessment of energy costs for granulation processes in different types of granulators is presented, which allows to justify the choice of rational parameters of the specified processes, taking into account energy costs and equipment efficiency. Equations are presented for determining the amount of exergy of material flows and exergy losses caused by heat exchange at finite temperature differences of technological flows at the entrance to the device and at the exit from it. The equation for determining the exergy efficiency, which characterizes the energy efficiency of the technical system, is presented. The smaller the temperature difference for the technological flows at the exit from the device, the smaller the exergy losses, the higher the value of the exergy efficiency. and, accordingly, the device will have greater energy efficiency. An exergy analysis of granulation processes in granulation towers without a cooler, in granulation towers with a cooler, fluidized bed devices and multi-stage (shelf) devices was carried out. The analysis showed that the exergy efficiency for the specified granulation plants is equal to: 64 %, 71 %, 32 % and 96 %, respectively. The obtained research results can be applied in production conditions where granulation towers and devices of fluidized or suspended layers are used. Enterprises that plan to reduce energy costs and increase the environmental safety of their technological processes can implement improvements based on the proposed methods and equations. The application of research results will contribute to the selection of more rational indicators of the granule production process, which will increase the productivity and quality of the final product. [ABSTRACT FROM AUTHOR]

Introduction: The availability of high-quality gilthead seabream (Sparus aurata) larvae in larviculture represents a major bottleneck to the aquaculture. This challenge can be compounded by losses resulting from the emergence of a clinical disorder's symptomatology. In this study, the observed syndrome included a rotated positioning of the larval sagittal plane and in most cases leading eventually to death. Methods: Herein, we examined using amplicon sequencing of the 16S rDNA the bacterial communities associated with S. aurata larvae at different conditions (including both fish with no evidence of the syndrome and fish with syndrome) during the early developmental stages along with the contribution of rearing water, organic matter and provided feed in the microbiota during an experiment of 18 days. Results: Over the development of larvae, differences were observed in the bacterial composition between healthy and symptomatic larvae as well as between components of the system. A remarkable presence of members of the Psychrobacter genus was observed in symptomatic larvaewith a significant increase at 18dph. The healthy larvae harbor different bacterial profile with a dominance of Vibrio and Bacillus genera during 3-8dph, various members of Alphaproteobacteria during 11-14dph and Marinifilum at 18dph. The rearing water showed a different bacterial profile compared to the other components, with a slight effect of healthy larvae at 3-8dph. The bacteriome of feeds provided during the rearing of larvae was found to be diverse. Chlorella was mainly dominated by members of Firmicutes, while Rotifer and Artemia were mainly dominated bymembers of Proteobacteria including different species of Psychrobacter. At 18dph, Artemia feed seems to affect the symptomatic larvae bacteriome, where it enhanced the presence of Psychrobacter spp. Discussion: Interestingly, the comparative network analysis at 18dph indicated that the bacterial associations in symptomatic larvae were primarily driven by members of the Psychrobacter genus. While various phyla contributed to bacterial associations in healthy larvae with different frequencies including mainly members of Proteobacteria, Bacteroidota and Firmicutes phyla. Finally, the Gammaproteobacteria/Alphaproteobacteria ratio was found to be related to the health condition of larvae. This study provides valuable informationwhich can be used as indicators for monitoring the health status of S. aurata larvae. [ABSTRACT FROM AUTHOR]

This work introduces two innovative rolling pair concepts to minimize slippage and reduce mass in cam-roller systems of large-scale hydraulic drivetrains: The variable contact length and the Shifting Contact Geometry concepts. Both aim to improve traction in the low contact force phase in cyclically loaded rolling contacts. The shifting contact geometry concept was validated using three custom rolling contacts: a line contact, a double elliptical contact, and a combination of both (i.e., shifting contact geometry). The tests were conducted under synchronized cyclic loading to mimic the conditions in a hydraulic drivetrain. Furthermore, a model from previous work was implemented to make predictions and compare them against the experimental results. During preliminary tests, the double elliptical contact displayed superior tractive behavior than the line contact under the same load thanks to higher contact pressures. Under synchronized cyclic loading, the line contact displayed high sensitivity to applied resisting torques at low contact forces, leading to high slide-to-roll ratios and traction force peaks. In contrast, the rolling pair with shifting contact geometry exhibited minimum slippage even under high resisting torques, resulting in substantially lower (and in most cases negligible) slide-to-roll ratio and traction force peaks. The simulations also captured this behavior, proving the validity of the model for predicting and comparing the rolling-sliding dynamics of these two different rolling pairs. This study demonstrates that rolling pairs with shifting contact geometry can not only improve the tribological performance of cam-roller contacts in large-scale hydraulic drivetrains but also yield a more favorable dynamic behavior. [ABSTRACT FROM AUTHOR]

Sunflower (Helianthus annuus L.), a vital crop for global vegetable oil production, encounters sustainability challenges in its cultivation. This study assesses the effects of incorporating a winter cover crop (CC), Avena sativa (L.), on the subsequent growth of sunflower crops and the vitality of their rhizosphere microbial communities over a two-year period. It examines the impact of two methods for suppressing winter CC--chemical suppression using glyphosate and mechanical suppression via rolling--both with and without the addition of phosphorus (P) starter fertilizer. These approaches are evaluated in comparison to the regional best management practices for sunflower cultivation, which involve a preparatory chemical fallow period and the subsequent application of starter P fertilizer. The methodology utilized Illumina sequencing for the analysis of rhizosphere bacterial 16S rRNA genes and fungal internal transcribed spacer (ITS) amplicons. Findings indicate a significant improvement (9-37%) in sunflower growth parameters (plant height, stem diameter, head diameter, and head dry weight) when cultivated after glyphosate-suppressed winter CC compared to the chemical fallows. Conversely, rolling of winter CC generally negatively affected sunflower growth. Rhizosphere bacterial communities following chemical suppression of winter CC showed greater Pielou's evenness, indicating a uniform distribution of species. In general, this treatment had more detrimental effects on beneficial sunflower rhizosphere bacteria such as Hymenobacter and Pseudarthrobacter than rolling of the winter CC, suggesting that the overall effect on sunflower growth may be mitigated by the redundancy within the bacterial community. As for fungal diversity, measured by the Chao-1 index, it increased in sunflowers planted after winter CC and receiving P fertilization, underscoring nutrient management's role in microbial community structure. Significant positive correlations between fungal diversity and sunflower growth parameters at the reproductive stage were observed (r = 0.41-0.72; p < 0.05), highlighting the role of fungal communities in plant fitness. The study underscores the positive effects of winter CC inclusion and management for enhancing sunflower cultivation while promoting beneficial microbes in the crop's rhizosphere. We advocate for strategic winter CC species selection, optimization of mechanical suppression techniques, and tailored phosphorus fertilization of sunflower to foster sustainable agriculture. [ABSTRACT FROM AUTHOR]

In this study, using an example of cold-rolled sheets, the separate effect of magnesium and zinc in an amount up to 2% upon the structure and mechanical properties of a thermally non-hardening heat-resistant alloy Al–2%Cu–1.5%Mn, the composition of which is optimized to obtain the maximum fraction of Al20Cu2Mn3 phase, is studied. It is found that in a cast state, zinc is completely contained within aluminum solid solution, and magnesium is partially included within eutectic particles of the Al2CuMg phase. These elements hardly affect the amount of Al20Cu2Mn3 phase, which is formed during deformation and heat treatment in the form of nanoscale dispersoids. It is found that addition of 1% magnesium increases the strength of cold-rolled sheets of the base alloy by 15% after 3‑hour annealing at 400 °C, without reducing the ductility. In turn, alloying with zinc does not have a significant effect on strength. [ABSTRACT FROM AUTHOR]

The aim of the work is to develop a physical and mathematical model of the process under complex asymmetric loading in conditions of single-area and two-area deformation zone during plastic processing of medium-thickness strips. The stress state in case of loss of stability during rolling of strips of medium thickness was investigated. The patterns of changes in the stress state of the strip under conditions of reach of the limiting deformation zone, as well as the effects of plastic shaping determined by a decrease in contact stresses under conditions of increasing deformation loading, are revealed. The described method is a visual approach to assessing the stress state of a plastic medium under conditions of complex interaction and asymmetric loading. [ABSTRACT FROM AUTHOR]

• Role of Ca/Al ratio in AXM Mg alloy systems for the mechanical behavior. • Influence of amount of alloying elements like Al, Ca, and Mn on the formation of precipitation in AXM Mg alloy systems. • Significance of precipitate formation in monoatomic layer G.P zones for enhancing both strength and ductility. • Importance of co-segregation behavior to enhance the stretch formability of the AXM Mg alloy systems. Automobiles are the inevitable mode of transportation. However, increasing fuel prices and carbon dioxide emissions are posing a serious threat to automobile users and the environment. Thus, the development of new lightweight materials has been a key area of research. Magnesium-based commercial alloys (AZ and ZK series alloys) are the lightest among all structural metals. However, there is still a question about the replacement of Aluminum-based alloys due to HCP crystal structure. In this connection, Mg Al Ca Mn (AXM) Mg alloy can be a choice as an alternative to the existing Mg-based commercial alloys for structural applications. It contains (Al, Mg) 2 Ca, Al 2 Ca, Mg 2 Ca, and Al 8 Mn 5 as the secondary phases, contributing to the microstructural refinement and property enhancement. However, the formation of those precipitates depends on the amount of Al, Ca, and Mn, especially, the Ca/Al ratio. In addition, the secondary processes influence the grain refinement and property enhancement of texture modifications. Hence, this review article focuses on elaborating on the significance of the Ca/Al ratio for the precipitate formation, secondary process, and texture modifications. The co-segregation behavior of other micro-alloying elements like Cerium, Lanthanum, and Zinc in AXM Mg alloy systems has also been discussed for property enhancement. [Display omitted] [ABSTRACT FROM AUTHOR]

A mathematical model is developed for preparing a tool control program in the finishing and hardening of a complex workpiece with a cycloidal helical surface by surface plastic deformation. [ABSTRACT FROM AUTHOR]

Tea, this popular drink, is produced in several ways; one of the methods used in Iran for tea processing is the orthodox method. In this method, the tea is first added and then rubbed, and after passing through the fermentation period, it enters the dryer. This research evaluated two parameters To check the quality of tea in the rubbing section: the speed and the distance of the cylinder from the bottom of the machine. To investigate the effect of the speed and distance of the cylinder on the quality of the final tea, first, using Solidwork software, a device similar to rubbing tea in an orthodox way with a capacity of 10 kg was designed and built. After weighing, the samples were divided into 10 kg parts and rubbed 27 times with speeds of 20, 30, and 40 rpm and distances of 2, 3, and 4 cm and with a 10 kg household tea rubbing machine. The rubbed samples were examined in terms of failure percentage and rubbing time. According to the analysis of the results and the analysis of the average comparison tables, it was observed that there is a significant difference between the values of percentage of failure and time in the constant cycle among all the distance levels, and the lower the distance of the cylinder from the bottom of the machine, the higher the percentage of failure and the rubbing time. It will be shorter. At a fixed distance between some levels of rotation speed, there is no significant difference between the time values, which varies according to the distance. Still, the failure percentage values at a fixed distance are significantly different, and the higher the rotation speed, the higher the percentage of failure. Due to the need for speed, while maintaining quality, the recommended speed and distance is 20 RPM, and the distance is 3 cm. [ABSTRACT FROM AUTHOR]

In this study, intermediate rolling processes, such as warm rolling (WR) before aging, hot rolling (HR) before quenching, and a combination of these processes, were used to process 7055 and 7075 alloys with solution and aging treatment. Intermediate rolling did not change the grain structure of 7055 alloy, but it refined the grain of 7075 alloy. Moreover, it led to the formation of dislocations in the alloys, thereby promoting the precipitation of η′ phases during subsequent aging. The low cooling rate resulted in the formation of η phases with large size and high-volume fraction in HR 7055 alloy. However, intermediate rolling did not seriously coarsen the precipitates of 7075 alloy due to its low Zn + Mg content, low Zn/Mg ratio, and high density of Cr-rich phases. WR before aging enhanced the strength of 7055 alloy, but other intermediate rolling processes seriously deteriorated its mechanical properties. The strength of 7075 alloy could be enhanced by all intermediate rolling processes, and the dislocation strengthening effect in 7075 alloy was more significant than its precipitation strengthening. [ABSTRACT FROM AUTHOR]

A comprehensive experimental study was conducted on EN8 steel samples subjected to hot rolling at various temperatures and with different numbers of passes. The research investigates the influence of these rolling parameters on the material's microstructure, hardness, and magnetic properties. The study includes controlled heating to specific temperatures, precise adjustments of roll spacing, and meticulous monitoring of rolling parameters. Key findings include the microstructural evolution during hot rolling, with grain refinement and phase transition, notably influenced by temperature. The data also reveals the relationship between rolling conditions, material hardness, and percentage of recrystallization, offering insights into optimizing material properties. Furthermore, the study presents an in-depth analysis of the Barkhausen peak's behavior concerning temperature, showcasing its potential for non-destructive hardness evaluation. Overall, this research provides valuable knowledge for material engineers and manufacturers aiming to tailor EN8 steel properties through optimized rolling and heat treatment processes. [ABSTRACT FROM AUTHOR]

In classical experiments, it has been found that a rigid cylinder can roll both on and under an inclined rubber plane with a friction force that depends on a power law of velocity, independent of the sign of the normal force. Further, contact area increases significantly with velocity with a related power law. We try to model qualitatively these experiments with a numerical boundary element solution with a standard linear solid and we find for sufficiently large Maugis–Tabor parameter λ qualitative agreement with experiments. However, friction force increases linearly with velocity at low velocities (like in the case with no adhesive hysteresis) and then decays at large speeds. Quantitative agreement with the Persson–Brener theory of crack propagation is found for the two power law regimes, but when Maugis–Tabor parameter λ is small, the cut-off stress in Persson–Brener theory depends on all the other dimensionless parameters of the problem. [ABSTRACT FROM AUTHOR]

Acne scarring is common and can occur even with effective acne management. In addition, patients with acne scarring suffer from significant psychosocial morbidity, including depression and suicidality. Despite the availability and advancement of therapeutic modalities, treatment for acne scarring is not always optimized and often overlooked in patients with acne encounters. Using acne scarring assessment tools and identifying specific acne scar subtypes allows for a tailored therapeutic approach. Part I of this continuing medical education series covers the pathophysiology and morphology of textural and pigmented acne scars, scarring assessment tools, and medical treatment options. The principles reviewed will aid in approaching and initiating acne scar treatment in the outpatient setting. [ABSTRACT FROM AUTHOR]

Tibiofemoral slip velocity is a key contributor to total knee arthroplasty (TKA) component wear, yet few studies have evaluated this quantity in vivo. The aim of the present study was to measure and compare tibiofemoral slip velocities in 3 TKA designs for a range of daily activities. Mobile biplane X-ray imaging was used to measure 6-degree-of-freedom tibiofemoral kinematics and the locations of articular contact in 75 patients implanted with a posterior-stabilized, cruciate-retaining, or medial-stabilized design while each patient performed level walking, step up, step down, sit-to-stand, and stand-to-sit. Using these data, tibiofemoral slip velocity was calculated for the duration of each activity for each TKA design. The pattern of tibiofemoral slip velocity was similar for all 3 TKA designs within each activity but markedly different across the 5 activities tested, with the magnitude of peak slip velocity being significantly higher in level walking (range: 158–211 mm/s) than in all other activities (range: 43–75 mm/s). The pattern of tibiofemoral slip velocity in both the medial and lateral compartments closely resembled the pattern of tibiofemoral (knee) flexion angular velocity, with a strong linear relationship observed between slip velocity and flexion angular velocity (r = 0.81–0.97). Tibiofemoral slip velocity was invariant to TKA design but was significantly affected by activity type. Our measurements of slip velocity and articular contact locations for a wide range of daily activities may be used as inputs in joint simulator testing protocols and computational models developed to estimate TKA component wear. [ABSTRACT FROM AUTHOR]

For bulk material it is very well known, that the material properties differ between the material near the surface and the inner material (i.e. segregations). However, for sheet material a gradient of material properties in depth direction and its influence on forming processes was not yet investigated. Within experiments on sheet steel 1.0338 (DC04) a gradient in material properties was proven by hardness measurements for both unprocessed material as well as after conducting forming and milling processes. The characterisation shows a gradient in material hardness over the entire sheet thickness. The experimental results regarding forming processes, such as rolling and bending, additionally show an increase of the materials hardness due to work hardening. The problem from the inhomogeneous material properties leads to an inaccurate prediction of the forming behaviour of the workpiece in further processing. Machining experiments were conducted for transferring the knowledge of modified surface and subsurface layers onto forming processes and their simulation. The bending experiments and the corresponding process simulation of the spring back behaviour show, that the implementation of an inhomogeneous material property increases the prediction accuracy. Notably the prediction of the spring back behaviour of thinner sheet metals is highly improved. Therefore, an analysis of sheet metal properties in thickness direction and their consideration in forming process simulations is inevitable for the implementation of accurate material models. [ABSTRACT FROM AUTHOR]

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The application of biodegradable Zn-based vascular alloy stents proves to be an ideal solution for addressing cardiovascular diseases. In this work, a Zn-0.8Li-0.4Mn alloy is designed with no biological toxicity, and optimized microstructure and properties through a hot rolling process. The resulting alloy shows a combined enhancement in both mechanical strength and resistance to corrosion. Noteworthy is the effectiveness of rolling deformation in refining alloy grains, promoting the uniform distribution of precipitates, and enhancing strength and ductility. After 90 % deformation, the Zn-0.8Li-0.4Mn alloy demonstrates excellent mechanical properties, with peak yield strength and ultimate tensile strength of 406.0 MPa and 449.1 MPa, respectively, and elongation exceeding 75 %. Corrosion studies indicate a relationship between the degradation rate increase and grain refinement, with the primary corrosion mechanism being pitting corrosion. The corrosion product Li2CO3 exhibits high stability, providing a passivation effect on the alloy surface. This work establishes a theoretical foundation and practical reference for the development of new biodegradable Zn-based alloys tailored for biomedical applications.

In this work, Mg–7Y–5Zn-0.1V alloys were prepared by 1-D forging followed by multi-step rolling. The rolling reduction dependence of the microstructure and tensile properties of the Mg–7Y–5Zn-0.1V alloy was experimentally investigated. The results indicated that the bimodal matrix microstructures are formed, and the fibrous 18R long-period stacking ordered (LPSO) phase and kinked 14H-LPSO phase are observed after 1-D forging. As the rolling deformation increased, the fibrous 18R-LPSO fractured into block and distributed more homogeneous. The lamellar 14H-LPSO fractured more severely, and it re-precipitated within the matrix when the deformation reached 50 %. The average grain size decreased gradually with increasing rolling deformation, and the minimum was 5.07 μm. After rolling, the {0001} and {0001} textures disappeared. The grain refinement of rolling alloy was mainly due to the fact that dynamic recrystallization (DRX) and substructures were generated within some grains, while the forging alloy was mainly due to DRX. The mechanisms of DRX were discontinuous DRX (DDRX) and twin-induced DRX (TDRX) after forging, and continuous DRX (CDRX) and DDRX after rolling. The strength reached its maximum when the rolling deformation amount reached 60 %, with a yield strength (YS) of 350 MPa and an ultimate tensile strength (UTS) of 385 MPa. Compared to the as-cast Mg–7Y–5Zn-0.1V alloy, its strength increased by 56 % and 63 %, respectively. The improvement of mechanical properties was mainly attributed to fine grain strengthening and dislocation strengthening.