Texture Morphology Research Articles

Directed Energy Deposition With Coaxial Wire-Powder Feeding: Melt Pool Temperature and Microstructure

Abstract In this work, we developed a new additive manufacturing paradigm, coaxial wire–powder-fed directed energy deposition (CWP-DED), to enable the fabrication of metals or composites with high manufacturing flexibility and efficiency. Herein, stainless steel (SS) 316L was selected as a representative material to validate the feasibility of CWP-DED process. Effects of feed rates on the melt pool temperature during the CWP-DED process were investigated using experimental and analytical approaches. Thermal contributions of fed wire and powders to the melt pool were involved in the analytical model to predict the melt pool temperature. The experimental results from thermal imaging were also obtained for validation. Besides, we uncovered the evolution of solidification morphology and crystallographic texture with different combinations of wire and powder feed rates. Finally, the microhardness and tensile performance of different as-built parts were tested. The results showed that the powder feed rate played a more dominant role in determining the melt pool temperature than the wire feed rate. Melt pool temperature experienced an initial increase and then decrease with the powder feed rate. A fine microstructure was achieved at a low powder feed rate, producing higher microhardness and larger tensile strength. This paper revealed the relations among process, thermal variation, and microstructure of as-built metallic parts to well understand this novel DED process.

Influence of phase morphology, static recrystallization, and crystallographic texture on room temperature tensile properties of Ti–6Al–4V alloy: Comparison between post-tested equiaxed, bimodal, and lamellar microstructures

The influence of phase fractions, morphology, recrystallization, and crystallographic texture on the room temperature uniaxial tensile properties were investigated in a Ti–6Al–4V (Ti-64) alloy. The hot rolled and annealed Ti-64 alloy was heat treated to generate three different microstructures (equiaxed, bimodal, and lamellar) with varying volume fractions and dimensions of constituent phases (equiaxed primary α, transformed α laths, and β laths). The tested tensile specimens were characterized using techniques such as electron backscattered diffraction (EBSD), transmission electron microscopy (TEM), and X-Ray diffraction-based bulk texture analysis to determine the deformation mechanism of the alloy. Among three different microstructures, the equiaxed microstructure (α/β-900/950-FC) exhibited a superior strength-toughness combination, while the lamellar microstructure (β-1050-AC) displayed poor tensile properties. The bimodal microstructure (α/β-900/950-AC) showed intermediate tensile properties. Recrystallized α grains and their connectivity promoted an extended steady-state flow during deformation and ductile fracture. The bimodal microstructure work hardened faster as compared to the other two microstructures. TEM investigation on the post-tested microstructures showed that events such as dislocation multiplication and dislocation-dislocation interactions, formation of slip bands across the α grains, multiple slip and dislocation pile-ups contribute to hardening mechanisms during deformation. Whereas, slip transfer across α/α boundary and breaking of β laths are the events of softening mechanisms. The slip transfer across two adjacent α grains happens when the misalignment between grains is less than 10°. Equiaxed microstructures exhibited maximum slip transfer due to interconnected primary α grains. Bimodal microstructures (α/β-900/950-AC) exhibited slip transfer when a higher fraction of interconnected primary α is present in the microstructure. In contrast, the lamellar microstructure showed no evidence of slip transfer. The prism slip is the dominant active slip system in the equiaxed and bimodal microstructures. However, the lamellar microstructure with no primary α showed only the prismatic <c+a> and pyramidal <a> slip activities.

High‐Temperature Fracture Growth by Constrained Sintering of Jadeite and Quartz Aggregates

AbstractFractures control heat and mass transfer and rheology in a wide range of subsurface regimes, ranging from low‐temperature diagenetic environments to high‐temperature metamorphic and magmatic systems. To investigate processes of opening‐mode fracture growth at high homologous temperature, we conducted constrained high‐temperature sintering experiments of thin layers of porous jadeite and quartz aggregate attached to a non‐sintering mullite substrate. Samples were heated stepwise at a low rate in a muffle furnace from 25°C to 1,000°C under ambient air pressure and examined for changes in mineral composition, texture, porosity, and fracture morphology using powder‐X‐ray diffraction, macro‐photography, reflected incident light microscopy, and secondary electron microscopy. Mineral reactions in the jadeite and quartz sample layer include jadeite and quartz reacting to albite at 600°C and the formation of nepheline and orthoclase at 900°C and 1,000°C. Opening‐mode fractures are first observed at 850°C coincident with the first presence of a melt phase with low aperture‐to‐length ratios similar to elastic‐brittle fractures. At 900°C, melt becomes increasingly abundant, and fractures obtain ductile morphology with high aperture‐to length ratios and blunted tips resulting from fracture growth by growth and coalescence of larger pores at the expense of smaller pores. In the absence of an externally applied mechanical load, we conclude that fracture growth is driven primarily by sintering stress resulting from differential contraction between sample layer and substrate associated with high‐temperature mineral reactions, melt formation and redistribution, and changes in pore structure. Similar fracture processes may be relevant to the segregation and migration of melt in magmatic systems.

Additive manufacturing of interstitial-strengthened high entropy alloy: Scanning strategy dependent anisotropic mechanical properties

A non-equiatomic interstitial-strengthened high entropy alloy (iHEA), Fe49.5Mn30Co10Cr10C0.5 (at.%), is manufactured by laser powder-bed fusion (LPBF) with stripe and chessboard scanning strategies. The present study highlights the correlation between the laser scanning strategies with resulting microstructure, textures, and anisotropic mechanical properties in as-built iHEA. The results show that the LPBF processed iHEA exhibits an excellent strength-ductility synergy due to the combined deformation mechanisms of dislocation slip, martensite phase transformation- and nano twinning-induced plasticity. The samples printed by the stripe scanning strategy show more evident mechanical anisotropy than that of the chessboard-scanned samples. The difference in the degree of mechanical anisotropy is mainly attributed to the heterogeneous grain morphology and crystallographic texture resulted from different scanning strategies.

Complex displacement behavior during foaming gas drainage in 2D microfluidic networks

Foam injection, which can significantly reduce gas mobility and improve sweep efficiency, has been used as an enhanced oil recovery (EOR) technique for decades. In this work, a mechanistic pore network model is proposed to simulate foam propagation in porous media. The model includes wettability through critical pressures for pore filling events and tracks the motion of gas–water interface during foam propagation process. It also allows a quantitative assessment of the thermodynamic and flow properties of foam, such as mobilization pressure gradient, invasion morphology, and foam texture evolution.Our results show that the inclusion of wettability impacts the evolution of the capillary pressure signal, and the mobilization pressure gradient. Both increasing foam texture and reducing contact angle provide a similar effect on the invasion morphology: a transition from the regime of capillary fingering to compact displacement as indicated by fractal dimension and finger width. The effect of disorder depends on its coupling with wettability and foam texture: increasing disorder decreases the pattern compactness; decreasing contact angle or increasing foam texture smooths the gas–water interface, hence increasing compactness, leading to small sensitivity of the emergent pattern to disorder. The comparison between simulations and experiments shows that the proposed model is able to capture the relevant pore-level events that characterize the foaming gas drainage process in a microfluidic device filled with vertical posts and is reliable to be used for providing information needed for parameters in mechanistic foam simulators that are not accessible in conventional laboratory experiments.

Wavelet Transform Based Morphological Matching Area Selection for Underwater Gravity Gradient-Aided Navigation

Selection of gravity gradient matching area is one of the key techniques for underwater gravity gradient-aided navigation. The existing matching area selection methods ignore the high-resolution characteristics of the gravity gradient, resulting in inaccurate selection. Therefore, a frequency domain matching area selection method based on the high-resolution characteristics of the gravity gradient is proposed. The high-frequency information of gravity gradient reference map is extracted by wavelet transform, and the gravity gradient wavelet transform model is established. The morphological image texture segmentation method is proposed to extract the densely textured areas from the gravity gradient high-frequency image as the matching areas. Simulation results show that the proposed method can obtain the texture density, texture amplitude and texture direction in the matching area while obtaining the matching area with a matching rate higher than 90%. Compared with the existing methods, the matching areas obtained by the proposed method are more accurate and the calculation burden is reduced to less than 10% of the existing algorithm. Moreover, the more the trajectory is perpendicular to the texture inside the matching area, the higher is the matching rate.

Spall damage in laser-powder-bed-fusion manufactured Ti-6Al-4V: Mechanisms and microstructure effects

Spall damage of Ti-6Al-4V alloy fabricated via laser powder bed fusion (LPBF) is investigated via plate impact along the build direction (BD) and the transverse direction (TD), as regards its underlying mechanisms and microstructure effects. Conventional hot-rolled Ti-6Al-4V alloys processed with annealing and quenching are also examined for comparison. Hugoniot elastic limit (HEL) and spall strength of the LPBF-fabricated samples are derived from free-surface velocity histories, and are higher for the TD loading than for the BD loading. The LPBF-fabricated alloy has a lower HEL but similar spall strength compared to the conventionally fabricated alloys. Quantitative analysis of recovered samples reveals that, the number of cracks is smaller and the mean crack length is larger in the LPBF-fabricated and quenched hot-rolled samples containing α′ martensite laths than the annealed hot-rolled sample containing equiaxed α grains. For the LPBF-fabricated samples, the TD loading induces cracks of similar length along α′ grain boundaries (GBs) and α′{0001} planes, but much longer cracks along prior β GBs compared to the BD loading. Anisotropy in mechanical properties and damage is due to columnar prior β grains, morphological and crystallographic texture of α′ laths.

Mechanical Anisotropy of Selective Laser Melted Ti-6Al-4V Using a Reduced-order Crystal Plasticity Finite Element Model

In this study, a reduced-order crystal plasticity finite element (CPFE) model was developed to study the effects of the microstructural morphology and crystallographic texture on the mechanical anisotropy of selective laser melted (SLMed) Ti-6Al-4V. First, both hierarchical and equiaxed microstructures in columnar prior grains were modeled to examine the influence of the microstructural morphology on mechanical anisotropy. Second, the effects of crystallographic anisotropy and textural variability on mechanical anisotropy were investigated at the granular and representative volume element (RVE) scales, respectively. The results show that hierarchical and equiaxed CPFE models with the same crystallographic texture exhibit the same mechanical anisotropy. At the granular scale, the significance of crystallographic anisotropy varies with different crystal orientations. This indicates that the present SLMed Ti-6Al-4V sample with weak mechanical anisotropy resulted from the synthetic effect of crystallographic anisotropies at the granular scale. Therefore, combinations of various crystallographic textures were applied to the reduced-order CPFE model to design SLMed Ti-6Al-4V with different mechanical anisotropies. Thus, the crystallographic texture is considered the main controlling variable for the mechanical anisotropy of SLMed Ti-6Al-4V in this study.

Vitex doniana seed activated carbon for methylene blue adsorption: equilibrium and kinetics

This study evaluated the characteristics of zinc chloride modified vitex doniana seed activated carbon (VDZnCl2) for the removal of methylene blue. VDZnCl2 was characterized for textural properties, surface morphology and surface chemistry. Batch adsorption of methylene blue by VDZnCl2 was evaluated for the effects of concentration, contact time, adsorbent dosage, and solution pH. The surface area increased from 14 to 933 m2/g with porous texture to facilitate adsorption. The SEM micrograph showed varieties of pores with widened cavities. The FTIR spectra showed the characteristics of O–H and C=C groups commonly found in carbonaceous materials. The maximum methylene blue adsorption was recorded as 238 mg/g at concentration range of 1–800 mg/L and VDZnCl2 dosage of 50 mg. Sips isotherm fitted well with the equilibrium data, suggesting that the adsorption by VDZnCl2 was a physical process onto its heterogeneous surface, while the applicability of pseudo-first-order kinetics implies that external diffusion was the rate controlling mechanism. The performance put up by VDZnCl2 suggested that it is a potential adsorbent substitute for dye wastewater treatment.

ASR crack identification in bridges using deep learning and texture analysis

Alkali-Silica Reaction (ASR), commonly known as ‘concrete cancer,’ is an expansive reaction occurring over time between aggregate constituents and alkaline hydroxides from cement. As a destructive phenomenon, the need to detect the onset of ASR in concrete structures to ensure their long-term durability and structural integrity is thus evidenced. In the structural health monitoring field, vision-based approaches have been found to be viable, fast, and cost-effective in diagnosing numerous types of cracks using physical attributes and surface patterns. However, achieving high accuracy in detecting ASR cracks using traditional visual inspection techniques is challenging and time-consuming. Inspired by artificial intelligence technology, this paper proposes and evaluates a two-phase computer vision procedure for detecting and classifying ASR cracks utilizing a collection of ASR images recorded from several bridges in Queensland, Australia. In the first phase, the procedure compares common pre-trained CNN models to investigate their capability in classifying ASR cracks and to select the best-performed model. In the second phase, a novel Feature Enhancement Process (FEP) was first proposed to increase the contrast between ASR cracks and the heavily textured backgrounds within the images. Next, to better highlight the ASR crack features, the feature-adjusted images are processed further through different texture analysis algorithms including: (i) Texture Morphology, (ii) Adaptive thresholding, and (iii) Local range filtering. The study shows that the proposed FEP can improve the ASR crack classification accuracy of InceptionV3, which is the best CNN model selected from Phase 1, from 90.9% to 92.48%. Furthermore, by combining FEP with texture morphology, a robust two-stage tool for assessing ASR cracks can be made with an impressive validation accuracy of 94.07%. This research contributes towards the application of novel AI deep learning technology in providing cost-effective autonomous ASR crack classification tools to support the owners and managers of civil public works assets and other constructed infrastructures.

Organogel of Acai Oil in Cosmetics: Microstructure, Stability, Rheology and Mechanical Properties.

Organogel (OG) is a semi-solid material composed of gelling molecules organized in the presence of an appropriate organic solvent, through physical or chemical interactions, in a continuous net. This investigation aimed at preparing and characterizing an organogel from acai oil with hyaluronic acid (HA) structured by 12-hydroxystearic acid (12-HSA), aiming at topical anti-aging application. Organogels containing or not containing HA were analyzed by Fourier-transform Infrared Spectroscopy, polarized light optical microscopy, thermal analysis, texture analysis, rheology, HA quantification and oxidative stability. The organogel containing hyaluronic acid (OG + HA) has a spherulitic texture morphology with a net-like structure and absorption bands that evidenced the presence of HA in the three-dimensional net of organogel. The thermal analysis confirmed the gelation and the insertion of HA, as well as a good thermal stability, which is also confirmed by the study of oxidative stability carried out under different temperature conditions for 90 days. The texture and rheology studies indicated a viscoelastic behavior. HA quantification shows the efficiency of the HA cross-linking process in the three-dimensional net of organogel with 11.22 µg/mL for cross-linked HA. Thus, it is concluded that OG + HA shows potentially promising physicochemical characteristics for the development of a cosmetic system.

Nanopinhole Passivating Contact Si Solar Cells Fabricated with Metal‐Assisted Chemical Etching

AbstractMonocrystalline Si (c‐Si) solar cells with passivating contacts based on doped polycrystalline Si (poly‐Si) on ≈2.0 nm silicon oxide (SiOx) require &gt;1000 °C thermal processing to create conducting pinholes in the SiOx layer. However, this high thermal budget can induce bulk defects in the Czochralski c‐Si wafers used as the cell absorber layer. In this work, it is demonstrated that pinholes can instead be created using metal‐assisted chemical etching on planar or textured morphologies, at room temperature. This wet process creates up to 200 nm wide conducting pinholes that are directly observed with transmission electron and atomic force microscopies. High‐performance hole‐selective poly‐Si/SiNy/SiOx and electron‐selective poly‐Si/SiOx passivating contacts are fabricated and implemented in laboratory‐scale solar cells. This process development significantly broadens the range of passivation layer materials, their thicknesses, and surface morphologies, which enables the design of poly‐Si contacts with superior passivating quality.

Parametric Reconstruction of Traditional Village Morphology Based on the Space Gene Perspective—The Case Study of Xiaoxi Village in Western Hunan, China

Traditional settlement space contains regional, natural, economic, historical, and cultural characteristics. The spatial texture serves as a material carrier of rural life and production and a vital landscape resource for the traditional villages. Traditional rural settlements have formed relatively unique and stable spatial form genes over time, which contain the “order” and “law” of spatial creation traditionally established in villages. The metropolis erodes traditional village spaces due to fast socioeconomic development and urbanization. In addition, the lack of adequate recognition and continuation of spatial texture in current mainstream village construction planning methods also limits the ability of villages to adapt to environmental changes and promote self-repair and adjustment, which, in turn, causes the gradual disappearance of their distinctive appearance. The reason is the need for more quantitative research and planning on the genes controlling the evolution of spatial texture morphology in traditional villages. They are faced with issues such as blind construction and development, a fracture in the rural characteristic spatial texture inheritance, and a loss of the distinctive vernacular landscape. Adopting an objective and in-depth approach to the cognition of traditional village space texture is an essential demand for the preservation, optimization, and renewal of the spatial appearance of rural settlements. We use the spatial genes of village settlements as its starting point. It then uses the spatial texture of village settlements connected to gene information mining as its specific method. We investigate the autogenous law of traditional village spatial form and determine its application using the CityEngine parametric platform, digitalization, and 3D visualization as the applied technical means. The feasibility and implementation path of the parameterization technique are explored using the traditional village of Xiaoxi in western Hunan Province as an example. We effectively promote the integration of rural spatial landscape resources, feature assessment, optimization guidance, and management control and provide an innovative research perspective and scientific planning path for analyzing the spatial morphological evolution of traditional villages.

Coal char supported Ni catalysts prepared for CO2 methanation by hydrogenation

Catalytic CO2 methanation is a potential solution for conversion of CO2 into valuable products, and the catalyst plays a crucial role on the CO2 conversion and CH4 selectivity. However, some details involved in the CO2 methanation over the carbon supported Ni catalysts are not yet fully understood. In this work, commercial coal char (CC) supported Ni catalysts were designed and prepared by two different methods (impregnation-thermal treatment method and thermal treatment-impregnation method) for CO2 methanation. Effects of the preparation conditions (including the thermal treatment temperature and time, the mass ratio of CC:Ni and the preparation method), as well as the reaction temperature of CO2 methanation, were investigated on the catalyst morphology, reducibility, structure and catalytic performance. Fibrous Ni-CC catalyst is achieved and shows high CO2 conversion (72.9%–100%) and CH4 selectivity (>99.0%) during the 600-min methanation process. Adverse changes of the catalyst surface and textural properties, reducibility, particle size and morphology are the potential factors leading to the catalyst deactivation, and possible solutions resistant to the deactivation were analyzed and discussed. The CO2 methanation mechanism with the CO route was proposed based on the oxidation-reduction cycle of Ni in this work.

Enhancing the limit of uniaxial magnetic anisotropy induced by ion beam erosion

Artificial tailoring of magnetic anisotropy by manipulating interfacial morphology and film structure is of fundamental interest from an application point of view in spintronic and magnetic memory devices. This Letter reports an approach to engineer and enhance the strength of oblique incidence ion beam erosion (IBE)-induced in-plane uniaxial magnetic anisotropy (UMA) by simultaneous modification of film morphology and film texture. Cobalt film and Si substrate have been taken as a model system to meet this objective. Unlike conventional thin film deposition on ripple patterned substrate or post-growth IBE of film, we direct our effort to the sequential deposition and subsequent IBE of the film. Detailed in situ investigation shows that the film grows in a textured polycrystalline state with the formation of nanometric surface ripples. The film also exhibits pronounced UMA with an easy axis oriented parallel to the surface ripple direction. Remarkably, the induced UMA is about one order of magnitude larger than the IBE-induced UMA reported earlier. The capability of imposing in-plane crystallographic texture throughout the film layer gives rise to magneto-crystalline anisotropy along with the shape anisotropy of nanometric surface ripples, which enhances the strength of the UMA and illustrates the universal applicability of the present method.

Use of fat graft to correct facial asymmetries in patients undergoing Orthognathic Surgery: the systematic review

Introduction: Orthognathic Surgery (OS) aims to correct deformities of the bones of the maxilla and mandible. In this scenario, fat grafting is a powerful tool for corrections and also for facial aesthetic improvement together or after OS. The benefits of fat grafting during orthognathic surgery; to maximize aesthetic results, minimize swelling and optimize wound healing. Objective: To analyze the main clinical studies on the benefits and risks of facial fat grafting in orthognathic surgery, to know the current state of the art. Methods: It followed a systematic literature review model on the main clinical findings of orthognathic surgery and fat grafting, according to the rules of PRISMA. The research was carried out from January 2021 to May 2021 and developed based on Google Scholar, Scopus, PubMed, Ovid, Scielo, and Cochrane Library. The quality of the studies was based on the GRADE instrument and the risk of bias was analyzed according to the Cochrane instrument. Results: 123 studies were analyzed, with only 52 medium and high-quality studies selected, according to GRADE rules, and with risks of bias that do not compromise scientific development, based on the Cochrane instrument. Studies have shown that OS aims to establish harmonious facial esthetics, excellent functional occlusion, and improved airway conditions. As an important adjunct to OS, fat grafting is becoming more and more common due to its anti-inflammatory role and effects on facial swelling. High patient satisfaction with the results. Postoperative swelling resolved at week 12 in the fat graft group and persistent edema. The edema decrease over time, with almost complete resolution within 1 year, improvement in facial morphology, function, quality, and skin texture in most of their patients. The use of assisted lipo transfers containing mesenchymal stem cells derived from adipose tissue, enables improvement in skin quality, smoothing of wrinkles, pore size, and attenuation of pigmentation and resolution of scars. Furthermore, enrichment of the lipoaspirate with stem cells derived from adipose tissue increases graft retention. Conclusion: Most of the studies analyzed in this review study showed that fat grafting in orthognathic surgery is a safe and effective tool to improve wound healing, improve aesthetic results, present an anti-inflammatory effect and reduce edema.

Anti-inflammatory and collagenation effects of zinc oxide-based nanocomposites biosynthesised with Mentha longifolia leaf extract.

The integration of nanomaterials and herbal medicine has led to the design of new nanocomposites, which are therapeutically more effective. The purpose of this study was to prepare different zinc oxide (ZnO)-based nanoparticles (NPs) via Mentha longifolia extract based on gauze linen fibre and study its effects on wound healing. The textural properties, morphology, thermal stability, purity, spectroscopic and phase structure of nanoparticles were investigated. Subsequently, male Wistar rats were subjected to wounds in six different treatment groups: Group I: control; group II: ZnO/W prepared in water (W); group III: ZnO/M synthesised with Mentha longifolia (M) extract; group IV: ZnO/copper(II) oxide (CuO)/M nanocomposite synthesised with M extract; group IV: treated with ZnO/silver (Ag)/M nanocomposite; group V: treated with ZnO/Ag/M nanocomposite; and finally, group VI: treated with ZnO/CuO/Ag/M nanocomposite. In all groups, the wounds were treated for 21 days with prepared samples. Every seven days, after measuring the decreasing rate of the wound size, tissue samples from each group were taken for histopathological analysis. The prepared tissue sections were assessed by haematoxylin and eosin staining for the formation of the epidermis, dermis and muscular tissue, and Masson's Trichrome staining for the formation of collagen fibres. The results showed that the ZnO/CuO/Ag/M nanocomposite was a significantly more effective wound healing material in comparison with other samples (p<0.05). In this study, the integration of ZnO/CuO/Ag nanocomposites with secondary metabolites of Mentha longifolia gave rise to a superior combination, which could support different phases of wound healing via the regulation of cytokines and growth factors in the course of healing.

Investigation of the Effect of Morphological and Crystallographic Textures on the Ductility Limits of Thin Metal Sheets Using a Cpfem-Based Approach

Investigation of the Effect of Morphological and Crystallographic Textures on the Ductility Limits of Thin Metal Sheets Using a Cpfem-Based Approach

Effect of sucrose as an elicitor in increasing quercetin-3-O-rhamnoside (quercitrin) content of chrysanthemum (Chrysanthemum morifolium Ramat) callus culture based on harvest time differences.

Chrysanthemum (Chrysanthemum morifolium) contains secondary metabolites, such as flavonoid compounds, especially luteolin-7-glucoside and quercetin-3-O-rhamnoside (quercitrin), in its tissues. Utilizing sucrose as an elicitor through callus culture presents an alternative method to enhance the production of secondary metabolites. This research aimed to determine the best sucrose concentration and harvest time for maximizing quercitrin content in chrysanthemum callus culture. The research employed a completely randomized design with four treatment groups: 0, 30, 45, and 60 g/l of sucrose added to MS medium containing 4 ppm 2,4-dichlorophenoxyacetic acid (2,4-D). Callus samples were harvested on the 15th and 30th days of culture. The observed parameters included callus morphology (color and texture), fresh weight, dry weight, the diameter of the callus, and quercitrin content analyzed using high-performance liquid chromatography. The results showed that all callus cultures exhibited intermediate textures and varied colors, predominantly shades of brown. The treatment involving 45 g/l of sucrose with a 30th-day harvest yielded the highest fresh weight, dry weight, and quercitrin content, namely 2.108 g, 0.051 g, and 0.437 mg/g DW, respectively. Notably, the quercitrin content exhibited a 63.67% increase compared to the control.

DPMSLM Demagnetization Fault Detection Based on Texture Feature Analysis of Grayscale Fusion Image

This study investigates a novel image morphology texture feature extraction method to realize the demagnetization fault location and severity detection of double-sided permanent magnet synchronous linear motor (DPMSLM). Initially, according to the constraints of DPMSLMs topology structure, the three lines magnetic density signal in motor air gap is extracted by finite element analysis as effective fault signal. Then, the grayscale fusion image (GFI) method is introduced to transform 1D data signal to 2D fused grayscale image which can better describe the demagnetization fault information. The unique features are visualized using the image enhancement techniques, and the image morphology texture features such as the area, Euler number, perimeter operator, correlation of binary image and so on can be extracted to constitute the demagnetization fault indexes. In addition, fisher score (FS) is used for feature optimization which can reduce the feature dimension. Furthermore, the two-level multiverse optimization support vector machine (MVO-SVM) algorithm is established to conduct demagnetization fault classification. Comparison experiments with other classifiers show that the MVO-SVM has a high fault identification accuracy of more than 98.3% and low running time less than 2.57s. Finally, the motor prototype experiment results show that the proposed method can accurately identify the location and severity of DPMSLM demagnetization faults, and it is an effective and feasible method which can be applied in DPMLM batch demagnetization inspection before delivery.