Texture Size Research Articles

Enhancing the anti-wear performance of graphene sheets embedded carbon films through interface nanotexture fabricated on the substrate

The effect and mechanism of surface texture on friction have been extensively explored, such as storing the abrasive and reducing the real contact area. However, studying the impact of the interface texture remains crucial, especially as the texture size approaches the nanoscale. In the present work, the silicon substrate with different parameters nanotexture was fabricated using a metal-assisted chemical etching process, and the graphene sheets embedded carbon (GSEC) film was deposited on the nanotextured substrate via a low-energy electron irradiation process to produce the interface nanotextured carbon films. After the addition of the interface nanotexture, the tribological performance of carbon films exhibited significant enhancement, with the degree of improvement being influenced by the parameters of the interface nanotexture. A super-low wear rate was achieved, with a value of 6.54 ± 0.70 × 10−8 mm3/N m. The improved tribological performance is due to the enhancement of film-substrate adhesion strength facilitated by interface nanotexture, and its role in promoting the rapid formation of a stable transfer film on the counter-grinding ball. The carbon film with nanotexture displays a small size of the abrasive particles, which contributes to the stabilization of the friction process.

Bending properties and deformation micromechanisms of near-α titanium alloy sheets/foils considering initial texture characteristics and size effect

Clarifying the bending deformation behaviour of metal foils is essential for meeting the lightweighting requirements of metal honeycomb structures. This study selected Ti65 alloy specimens with various thicknesses and initial α-phase textures to conduct room-temperature three-point bending experiments. A detailed comparative analysis was performed on the bending deformation behaviour of Ti65 alloy sheets and foils. It reveals that in the foil specimens, the weakening effect of surface layer grains is significant. Under the influence of size effects, the springback angle of Ti65 alloy foils with coarse α-phase grains decreases markedly. Additionally, through various methods, including global Schmid factor analysis, lattice rotation analysis, and crystal plasticity finite element method simulations, the specific relationship between α-phase texture and the bending performance of Ti65 alloy foils was thoroughly investigated. The rolling process influences the bending performance of Ti65 alloy by determining the α-phase texture. Unidirectionally rolled Ti65 alloy products exhibit a transverse α-phase texture, which predisposes them to form transverse texture α-phase macrozones during bending. In contrast, cross-directionally rolled Ti65 alloy foils possess a basal α-phase texture biased toward the transverse direction. This not only helps avoid the formation of macrozones but also ensures coordinated deformation across the foil, resulting in superior bending performance.

Recent Advances and Applications of Passive Acoustic Monitoring in Assessing Shrimp Feeding Behaviour Under Laboratory and Farm Conditions

ABSTRACTThe use of passive acoustic monitoring (PAM) has recently been integrated with other noninvasive ethological methodologies to enhance the understanding of shrimp feeding behaviour, as their mandibles emit click sounds during food intake. This review aims to compile recent advances and various applications of PAM in assessing shrimp feeding behaviour under controlled laboratory and farm conditions. It includes a description of key concepts, terms and general methodologies in the field of bioacoustics to facilitate understanding of acoustic characterisation, specific methodologies and the main uses of PAM in shrimp research. Among the primary contributions of PAM in laboratory studies are acoustic characterisation of clicks and mandibular structures associated with their emission for different species; variations in acoustic click parameters related to animal size, feed texture and pellet size; and effects on feeding behaviour caused by shrimp size, stocking density and specific characteristics of artificial diets (texture, formulations, additives and pellet sizes). Finally, future perspectives and recommendations for laboratory studies using PAM are provided. The review highlights the contribution of PAM, which, allied with other ethological methodologies, emerges as a novel tool for researching shrimp behaviour and optimising feed management in aquaculture.

Surface Tribological Properties Enhancement Using Multivariate Linear Regression Optimization of Surface Micro-Texture

This work aims to provide a comprehensive understanding of the structural impact of micro-texture on the properties of bearing capacity and friction coefficient through numerical simulation and theoretical calculation. Compared to the traditional optimization method of single-factor analysis (SFA) and orthogonal experiment, the multivariate linear regression (MLA) algorithm can optimize the structure parameters of the micro-texture within a wider range and analyze the coupling effect of the parameters. Therefore, in this work, micro-textures with varying texture size, area ratio, depth, and geometry were designed, and their impact on the bearing capacity and friction coefficient was investigated using SFA and MLA algorithms. Both methods obtained the optimal structures, and their properties were compared. It was found that the MLA algorithm can further improve the friction coefficient based on the SFA results. The optimal friction coefficient of 0.070409 can be obtained using the SFA method with a size of 500 µm, an area ratio of 40%, a depth of 5 µm, and a geometry of the slit, having a 10.7% reduction compared with the texture-free surface. In comparison, the friction coefficient can be further reduced to 0.067844 by the MLA algorithm under the parameters of size of 600 µm, area ratio of 50%, depth of 9 µm, and geometry of the slit. The final optimal micro-texture surface shows a 15.6% reduction in the friction coefficient compared to the texture-free surfaces and a 4.9% reduction compared to the optimal surfaces obtained by SFA.

Dunking Pancreaticojejunostomy With Braun's Jejunojejunostomy: Perioperative Outcomes of a Hundred Pancreaticoduodenectomies.

Background The optimal surgical technique for pancreaticojejunostomy (PJ) following pancreaticoduodenectomy (PD) is still debated. Dunking and duct-to-mucosa PJ are the most commonly adopted techniques. Incorporating Braun's jejunojejunostomy (JJ) could reducetheincidence and severity of delayed gastric emptying (DGE). This retrospective descriptive study seeks to clarify the outcomes of dunking PJ with Braun's JJ in 100 PD patients. Methodology We retrospectively reviewed 100 patients who underwent PDs in a single unit of the Department of Surgical Gastroenterology of Tribhuvan University Teaching Hospital from October 2012 to February 2023. Demographic and historical data, indications, procedure-related data, complications, and mortality data were collected and analyzed. Results The mean age was 50.96 ± 14.97 years, and 64 (64%) were males. The most common indication was ampullary carcinoma (53, 53%) followed by distal cholangiocarcinoma (18, 18%) and pancreatic ductal adenocarcinoma (7, 7%). Operative time was 5.83 ± 1.09 hours, intraoperative blood loss was 515 ± 194 mL, and the average time for PJ and Braun's JJ was 22 ± 6 and 15 ± 3 minutes, respectively. Soft pancreas was encountered in 52 (52%) patients and clinically significant postoperative pancreatic fistula (Grade B, C) was seen in 23 (23%). Postpancreatectomy hemorrhage was seen in 21 (21%) patients (Grades A: 3, B: 12, C: 6). DGE (Grade B) occurred in two (2%) patients, and bile leak was observed in 4% of patients (Grades A: 1, B: 2, C: 1). Major complications (Clavien-Dindo ≥IIIA) occurred in 24%, and 11 patients died. Conclusions The dunking technique is easily adaptable, less time-consuming, and can be performed in the pancreas of any texture or duct size but is associated with an increased incidence of post-pancreatectomy hemorrhage. Incorporation of Braun's anastomosis lowers DGE, allows early initiation of feeding, and reduces complication rates.

Evaluation of the effect of texture size and rounding process on three-dimensional flexibility of c-Si wafer

Vehicles are expected to be a new application field for solar cells. Since vehicle bodies have complicated three-dimensional curved surfaces designed to improve aerodynamic performance, there is a need for flexible solar cells that can be installed on such surfaces. To this end, research has focused on single-crystalline Si solar cells with high conversion efficiency and reliability, since the flexibility of Si wafers improves as they become thinner. Previous studies have reported that the texture structure to improve the light absorption on the Si wafer surface affects the three-dimensional flexibility. In this work, we perform a Ball-on-Ring test to determine how texture size and rounding treatment affect the flexibility of c-Si wafers and measure the flexibility. The results demonstrate that the rounding process increases flexibility, while the texture size reduction improves flexibility.

Diagenesis of Cenomanian–Early Turonian and the Control of Carbonate Reservoirs in the Northern Central Arabian Basin

The carbonate reservoirs of Cenomanian–Early Turonian in the northeastern Central Arabian Basin hold considerable oil reserves and are great contributors to oil production. Diagenesis have a great impact on carbonate reservoir petrophysical properties, microstructure, and heterogeneity. By integrating cores, cast thin sections, regular core analysis, CT, and isotopes, this study provides an improved understanding of diagenesis in the Cenomanian–Early Turonian and its effect on carbonate reservoirs. The results showed that three diagenetic environments were identified in the Cenomanian–Early Turonian based on texture, structure, cement, crystal form, and crystal size, which were marine environment, meteoric environment, and burial environment. Six diageneses were identified based on residual bioclastic, secondary pores, calcite quantity, dolomite size, and stylolite, namely dissolution, cementation, micritization, dolomitization, compaction, and pressure solution. A micritization model in high energy sediment, a dolomitization model in burrows, and a comprehensive diagenetic model were established. It concluded that dissolution during meteoric environment is most favorable to reservoir physical properties, while cementation is least favorable. The cement content controls the microstructure and petrophysical property. Micritization is detrimental to the petrophysical properties, and the micrite it forms are distributed in the interparticle pores, reducing the reservoir property deposited in high energy environment. Dolomitization is less developed in substrate but widely developed in burrows, which result in the physical properties of the burrows being higher than those of substrate. Compaction and pressure solution have a negative impact on reservoir physical properties.

Contributions to the taxonomy of Periplocoideae and Asclepiadoideae (Apocynaceae) in Türkiye based on fruit and seed morphology

In this study, the fruit and seed morphology of all the Periplocoideae (Periploca gracilis and P. graeca) and the majority of Asclepiadoideae (Araujia sericifera, Cionura erecta, Cynanchum acutum and Gomphocarpus fruticosus) taxa in Türkiye was evaluated from a taxonomic point of view using, for the first time, both light and scanning electron microscopy. Macro- and micro-morphological investigations were carried out on herbarium samples. An identification key for the examined Periplocoideae and Asclepiadoideae taxa, and expanded fruit and seed descriptions for each taxon were prepared. Numerical analysis showed that shape and size of follicle, size, shape and surface texture of seed were found to be effective in delimiting the studied Periplocoideae and Asclepiadoideae taxa at subfamilial and generic levels.

Sediment distribution and transport pattern in the nearshore region, southeast coast of India

The present paper aimed to assess the sediment distribution pattern, mode of transport, and its interaction with hydrodynamic and topographic conditions at different depths and regions along the east coast of India. About 900 surficial sediment samples were collected and analysed on a monthly basis for the Chennai coastal region at 32 stations from 2013 to 2015. The study region is classified into four types, such as beach, inlet, 5 m, and 10 m depth. Sediment textural and grain size trend analyses were conducted to achieve the objectives. Sediment characteristics for the region were recorded as sandy, equally dominated by unimodal and bimodal at the beach, while unimodal at shallow depths (5 and 15 m). The sediments were medium sand to coarse sand at the beach, mostly fine followed by medium at 5 and 15 m depths. The sediment sorting is dominated by moderately well-sorted sediments; the skewness of beach sediments was negative, while nearshore sediments were found positive; average kurtosis values of sediments were noticed to be mesokurtic. The CM plot depicts that the sediments were mostly derived by tractive current, and the modes of transport are “bottom suspension and rolling” and “graded suspension no rolling” at beach locations and shallow water depths, respectively. The GSTA analysis reveals the annual average sediment transport pattern is northerly. The numerical hydrodynamic study confirms the GSTA and CM plot analysis. The study reveals a stable sedimentary environment south of the Chennai port and instability in the northern part. The study includes large spatiotemporal nearshore sediment data with hydrodynamic conditions, immensely helpful to coastal stakeholders and researchers.

Performance Evaluation and Optimization of 3D Models from Low-Cost 3D Scanning Technologies for Virtual Reality and Metaverse E-Commerce

Virtual Reality (VR) is and will be a key driver in the evolution of e-commerce, providing an immersive and gamified shopping experience. However, for VR shopping spaces to become a reality, retailers’ product catalogues must first be digitised into 3D models. While this may be a simple task for retail giants, it can be a major obstacle for small retailers, whose human and financial resources are often more limited, making them less competitive. Therefore, this paper presents an analysis of low-cost scanning technologies for small business owners to digitise their products and make them available on VR shopping platforms, with the aim of helping improve the competitiveness of small businesses through VR and Artificial Intelligence (AI). The technologies to be considered are photogrammetry, LiDAR sensors and NeRF.In addition to investigating which technology provides the best visual quality of 3D models based on metrics and quantitative results, these models must also offer good performance in commercial VR headsets. In this way, we also analyse the performance of such models when running on Meta Quest 2, Quest Pro and Quest 3 headsets (Reality Labs, Reality Labs, CA, USA) to determine their feasibility and provide use cases for each type of model from a scalability point of view. Finally, our work describes a model optimisation process that reduce the polygon count and texture size of high-poly models, converting them into more performance-friendly versions without significantly compromising visual quality.

Ultra-high strength of additively manufactured CoCrNi medium entropy alloy with high-fraction TiC

In this work, the novel CoCrNi composite with as high fraction as 5 wt% TiC reinforcements were additively manufactured (AMed) by laser powder bed fusion (LPBF) of blended powders of nano-C particles, spherical micro-Ti powders and spherical CoCrNi powders, instead of blended powders of nano-TiC and CoCrNi powders. This method resulted in fully melting of C and Ti elements during laser fusion and subsequent precipitation of nano-TiC during solidification. The agglomeration of nano-TiC in the matrix is reduced by this method, resulting in an 1800 MPa ultrahigh strength, simultaneously maintaining a considerable elongation of 12 %. Rise in the fractions of TiC from 0 to 5 wt% reduces intensity of the texture and grain size in the matrix and convert the strong 〈101〉 texture to relative weak 〈100〉 texture along building direction (BD).

Effect of initial grain size on microstructure, texture and magnetic properties of non-oriented electrical steel

The effect of initial grain size prior to cold rolling on the microstructure, texture evolution, and magnetic properties of Fe-3.5 wt% Si non-oriented electrical steel (NOES) was investigated through the introduction of normalization. There were massive intragranular shear bands in {111}<110> and {111}<112> deformed grains in the cold-rolled sheet with large initial grain size, providing nucleation sites for new recrystallized grains with Goss ({110}<001>), λ-fiber, γ-fiber, and {113}<631> components. Subsequent annealing resulted in weaker γ-fiber ({111}<110>−{111}<112>), stronger α*-fiber concentrated at {113}<631>, along with Goss and λ-fiber ({100}<001>−{100}<012>) textures. In addition, appropriate final annealing temperature effectively reduced iron loss. The simultaneous optimization of texture and grain size by normalization and annealing treatments led to improved magnetic properties, with the superior magnetic induction (B50 = 1.719) T, and the lowest core loss (P15/50 = 2.69 W/kg, P10/400 = 16.337 W/kg).

Particle size effects on silyl‐chromate/VOx/silica bimetallic catalyst for UHMWPE/HDPE in‐reactor blends

AbstractIn this work, four kinds of silica with similar textural properties but different particle size (PS) from 6 to 60 μm were selected as support to prepare silyl‐chromate/VOx/silica bimetallic catalysts for ethylene polymerization, thus making it possible to conduct convincing investigation on the effects of catalyst PS over catalytic behaviors and polymer properties. It is found, owing to mass‐ and heat‐transfer limitations, the catalysts with smaller PS showed higher initial activity, while the deactivation in the later stage was more remarkable. Meanwhile, catalysts with smaller PS synthesized bimodal ultrahigh molecular weight polyethylene/high‐density polyethylene in‐reactor blends (UHMWPE/HDPE IRBs) with higher molecular weight (MW) and narrower molecular weight distribution (MWD). Four PE sample couples with MW increasing from 5 × 105 to 10 × 105 g mol−1 and PS from 40 to 460 μm were selected for tensile and rheological tests. For each couple with similar MW and MWD, the sample with smaller PS always had larger tensile strength and breaking elongation. The cryogenically fractured surface of the samples made by smaller PE particles showed fewer delamination defects and unfused small particles. The rheological results indicate that higher homogeneity was achieved for the sample with smaller PS, which was reflected by the unexpected higher viscosity and storage modulus.

Crystal plasticity quantification of anisotropic tensile and fatigue properties in laser powder bed fused Inconel 718 superalloy

The high thermal gradients during the laser powder bed fusion (LPBF) process induce an inhomogeneous microstructure with anisotropic mechanical properties. This study developed a dislocation-based strain-gradient crystal plasticity finite element (CPFE) model to reveal the microstructure-based deformation mechanisms and quantify their strengthening contributions to the mechanical property anisotropy of LPBF-ed Inconel 718 (IN718) superalloy. The analyzed microstructural attributes included 1- crystallographic orientations/misorientations, 2- solid solutions (SS), 3- grain size and morphologies, and 4- dislocation dynamics, such as statistically stored dislocations (SSDs) and geometrically necessary dislocations (GNDs). The investigated mechanical properties contained tensile strength, fatigue resistance, fracture mechanisms, and their anisotropy under loading towards building (BD) and transverse (TD) directions. The experimentally obtained microstructural features of the as-LPBF-ed IN718 were synthesized into the crystal plasticity representative volume elements (CPRVE) to model the deformation behavior using a user-defined material subroutine (UMAT) in the ABAQUS solver. The energy-based fatigue indicator parameter (FIP) captured the fatigue properties and failure mechanisms. The main slip-strengthening contributions stemmed from SSDs, grain size, SS, and GNDs. in TD. The corresponding order in BD was SSDs, SS, GNDs, and grain size because the grain dimensions were larger in BD than in TD. The grain-size effect had the highest contribution to the tensile property anisotropy, followed by SSDs, GNDs, and SS. Aside from their strengthening effects, crystal texture and grain size induced mechanical property heterogeneity and fatigue sensitivity at grain boundaries, reducing their contributions to fatigue strength relative to tensile. In contrast to the previous findings, local accumulations of SSDs and GNDs at softer sides of grain boundaries during cyclic loading reduced the strength heterogeneity in these areas, improving fatigue properties. The highest slip-strengthening effect for fatigue resistance and anisotropy was under SSDs, followed by GNDs, SS, and grain size.

Simulation-trained machine learning models for Lorentz transmission electron microscopy

Understanding the collective behavior of complex spin textures, such as lattices of magnetic skyrmions, is of fundamental importance for exploring and controlling the emergent ordering of these spin textures and inducing phase transitions. It is also critical to understand the skyrmion–skyrmion interactions for applications such as magnetic skyrmion-enabled reservoir or neuromorphic computing. Magnetic skyrmion lattices can be studied using in situ Lorentz transmission electron microscopy (LTEM), but quantitative and statistically robust analysis of the skyrmion lattices from LTEM images can be difficult. In this work, we show that a convolutional neural network, trained on simulated data, can be applied to perform segmentation of spin textures and to extract quantitative data, such as spin texture size and location, from experimental LTEM images, which cannot be obtained manually. This includes quantitative information about skyrmion size, position, and shape, which can, in turn, be used to calculate skyrmion–skyrmion interactions and lattice ordering. We apply this approach to segmenting images of Néel skyrmion lattices so that we can accurately identify skyrmion size and deformation in both dense and sparse lattices. The model is trained using a large set of micromagnetic simulations as well as simulated LTEM images. This entirely open-source training pipeline can be applied to a wide variety of magnetic features and materials, enabling large-scale statistical studies of spin textures using LTEM.

Infrared Small Target Detection Based on Density Peak Search and Local Features

The detection of small infrared targets is still a challenging task and efficient and accurate detection plays a key role in modern infrared search and tracking military applications. However, small infrared targets are difficult to detect due to their weak brightness, small size and lack of shape, structure, texture, and other information elements. In this paper, we propose a target detection method. First, to address the problem that the proximity of targets to high-brightness clutter leads to missed detection of candidate targets, a Gaussian differential filtering preprocessed image is used to suppress high-brightness clutter. Second, a density-peaked global search method is used to determine the location of candidate targets in the preprocessed image. We then use local contrast to the candidate target points to enhance the gradient features and suppress background clutter. The Facet model is used to compute multidirectional gradient features at each point. A new efficient surrounding symmetric region partitioning scheme is constructed to capture the gradient characteristics of targets of different sizes in eight directions, followed by weighting the candidate target gradient characteristics using the standard deviation of the symmetric region difference. Finally, an adaptive threshold segmentation method is used to extract small targets. Experimental results show that the method proposed in this paper has better detection accuracy and robustness compared with other detection methods.

Regulating the microstructure and strength of the advancing side interface zone in AZ31 friction stir welded joint via localized selective remelting

Friction stir welding (FSW) is a solid-state welding technique widely used for various series of magnesium (Mg) alloys. However, in the process of transverse loading for FSW joints in Mg alloys, the ultimate fracture often occurs near the advancing side (AS) interface zone. To enhance the AS interface strength and overall joint strength, this research employed tungsten inert gas welding (TIG) arc to locally remelt the AS interface zone in the FSW-AZ31 joint. The microstructure characterization after remelting showed that two TIG melting zones were formed in the interface area between the AS and nugget zone (NZ). Within these zones, the grains exhibited significant coarsening and the texture intensity noticeably decreased. Conversely, the interface between the retreating side (RS) and NZ, being far from the TIG melting zone, experienced minimal changes in texture and grain size. Mechanical testing conducted at room temperature indicated that the joint ultimately fractured at the RS, resulting in an interface strength difference of ∼16 MPa between the AS and RS. The enhanced strength of the AS interface was attributed to the low Schmid factor of basal slip, reduced dislocation density, and pronounced twinning behavior.

Advancing precision acne therapy using a novel photopneumatic device

ABSTRACT Photopneumatic therapy (PPT) combines vacuum and pulsed, broadband light to extract debris and bacteria from the pilosebaceous units; monotherapy is unexplored. Facial acne lesions and skin texture were evaluated after up to six PPT treatments, 1–2 weeks apart for 15–20 minutes per treatment using customized energy settings, in seven female patients with inflammatory, comedonal and pustular lesions. Lesion and redness reduction with improvement in skin texture and pore size were observed after 1–3 treatments; adverse effects were infrequent. PPT may optimize lesion clearance as monotherapy and/or as an adjuvant. The ability to change pulse structure, pulse duration, vacuum pressure and fluence allow for treatment that best matches skin type and acne severity.

Does size matter? Morphological and content analysis of the coprolites from a Quaternary deposit in the Iberian Peninsula

Coprolites are very abundant in Quaternary deposits. However, they are often overlooked despite offering insights into both the surrounding environment and the species that produced them, particularly when skeletal remains are absent. We selected a Quaternary cave deposit from the Iberian Peninsula, Juan Labranz Cave, where an abundant and diverse coprolite collection was recovered, in order to develop a non-destructive study method that allows an accurate interpretation of the producer. Morphometric analyses of these specimens reveal two distinctive morphotypes associated with the two main carnivore occupations in the cave, hyaenas and bears. Morphotype I resembles hyaena coprolites in shape, texture, and bone inclusions, suggesting spotted hyaena as the most likely producer based on size. On the other hand, morphotype II deviates significantly, with a wrinkled texture and larger size, resembling bear faeces when eating carrion. Differences in bone fragment size and the presence of hair moulds further support these attributions. In conclusion, this study underlines the importance of considering taphonomy, morphology, size, and content in identifying coprolite producers, also high- lighting the relevance of these ichnofossils as indirect evidence of species and for the understanding of their ecological roles in Quaternary environments, where humans and other predators coexist.

Experiment and modelling of texture and sliding direction dependence on finger friction behavior

Humans rely on their fingers to sense and interact with external environment. Understanding the tribological behavior between finger skin and object surface is crucial for various fields, including tactile perception, product appearance design, and electronic skin research. Quantitatively describing finger frictional behavior is always challenging, given the complex structure of the finger. In this study, the texture and sliding direction dependence of finger skin friction was quantified based on explicit mathematic models. The proposed double-layer model of finger skin effectively described the nonlinear elastic response of skin and predicted the scaling-law of effective elastic modulus with contact radius. Additionally, the skin friction model on textured surface considering adhesion and deformation factors was established. It revealed that adhesive term dominated finger friction behavior in daily life, and suggested that object texture size mainly influenced friction-induced vibrations rather than the average friction force. Combined with digital image correlation (DIC) technique, the effect of sliding direction on finger friction was analyzed. It was found that the anisotropy in finger friction was governed by the finger’s ratchet pawl structure, which also contributes to enhanced stick-slip vibrations in the distal sliding direction. The proposed friction models can offer valuable insights into the underlying mechanism of skin friction under various operating conditions, and can provide quantitative guidance for effectively encoding friction into haptics.