Edge Of Layer Research Articles

How to Combine SHJ Cell-Edge Passivation and Module Reliability?

The use of cut-cells in most of the current modules is now the norm to maximise the final product performances. But the integration of such new cell configurations also comes with new challenges, especially if small cell size dimensions such as shingle are considered. Indeed, specific edge passivation processes are often used to recover for the cut-cell losses. Alumina Oxide or Polymer deposition are the most studied approaches, with in general promising benefits proven at cell level. However, only few communications after module integration are available, in particular about the impact of these additional layers on final module reliability. We show for example that it is crucial to avoid direct deposition of AlOX over the cell metal pattern in the future interconnection area, as TC (Thermal Cycling) resilience of such modules is clearly degraded. Proper edge localization of the AlOX layer is needed to recover the initial reliability behaviour. To preserve the interconnection quality, three different approaches are investigated: (1) edge localisation of the layer by wafer stacking during deposition (2) introduction of adapted copper plating solutions allowing metal growth through the passivation layer (3) edge passivation process directly applied on final strings just before lamination.

Light and electron microscopy of the micromorphology and development of pycniospores and aeciospores of the sunflower rust, Puccinia helianthi

The pathogenic fungus Puccinia helianthi, which causes rust disease and significant economic loss, poses a serious threat to the Helianthus annuus crop. This study is the first to examine the ultrastructure of the spore stages of this rust, aiming to fill the gap in the understanding of Egyptian rusts. The present study aimed to explore the micromorphology and development of pycniospores and aeciospores of Puccinia helianthi on its host, using LM, SEM, and TEM. The immature pycnium grows subepidermally and is bordered by a peripheral layer of pseudoparenchymatous cells. Within the pycnium, uninuclear, compactly packed, and elongated pycniosporophores are formed. Pointed periphyses emerge at the highest point of the pycnium, where numerous pycniospores are produced. The primary pycniospores are then released from the pycniosporophores having an elliptical shape with a wrinkled surface. Aeciospores are produced at the edges of a distinct layer, the peridium with rhomboid-shaped peridial cells. A prosenchymatous stroma develops beneath the hymenium layer (aeciosporophores). Two main types of hyphae can distinguish in this stroma: vacuolated hyphae, at the base of the aecium, and non-vacuolated hyphae with dense, ribosome-rich cytoplasm, oil droplets, and glycogen. Each aeciospore divides to form a young aeciospore and an intercalary cell with elongated or hexagonal shapes and warts on the mature aeciospores. SEM examination reveals cog-like ornaments and refracting bodies on the surfaces of peridial cells and aeciospores. The ultrastructure of these two spore stages is more or less similar to that of other Puccinia species with some differences. The procedures used in this study will assist mycologists in rust identification, taxonomy, and microscopic characterization. In conclusion, this study will provide additional information to help understand the interaction between rusts and their hosts. Future research on ultracytochemical studies may provide insight into controlling these serious pathogens.

Extraction of two-magnon scattering and detection of inverse spin Hall effect up to 40 GHz in low-damping Fe65Co35/Pt bilayer thin film

Abstract We report an investigation of the inverse spin Hall effect (ISHE), as a measure of the pure spin current (J S ), induced by spin pumping in a Fe65Co35/Pt bilayer using coplanar waveguide ferromagnetic resonance (CPW-FMR) in the in-plane (IP) geometry over the broadband microwave frequency range of 8–40 GHz. From the IP-FMR measurements, the defect-induced two-magnon scattering (TMS) contribution is evaluated by analyzing the frequency dependence of FMR linewidth using Arias and Mills approach [Arias R and Mills D L (1999 Phys. Rev. B 60, 7395), Mills D L and Arias R (2006 Physica B 384 147–151)]. Here, we have determined a very low Gilbert damping constant (α G ) for Fe65Co35 bare film around 1.3 × 10−3, which is essential for the high spin current (>107 A/m2) generation. The enhanced value of α G ≈3.2 × 10−3 obtained for Fe65Co35/Pt bilayer film is due to spin pumping damping, α SP = 1.9 × 10−3, confirmed by the ISHE induced DC voltage (V DC ) signal measured across the edges of Pt layer. Out-of-plane (OP) angular ISHE measurements have been performed to disentangle spin pumping from spin rectification effects in the V DC signal. Further, we evaluated the effective spin-mixing conductance g eff ↑ ↓ = 3.33 × 1019 m−2, which is higher than the values reported in FeCo-alloy-based bilayer systems. The present study aims to detect the J S injected by low-damping Fe65Co35 thin films, leading to the realization of energy-efficient spintronic devices.

Three-dimensional finite element analysis of occlusal stress on maxillary first molars with different marginal morphologies restored with occlusal veneers

BackgroundThere are differences in the research results regarding which edge design of occlusal veneers can achieve the best long-term success rate as a relatively new fixed prosthesis restoration method. Further research is needed. The three-dimensional finite element method was used to conduct stress analysis on occlusal veneers of maxillary first permanent molars with different thicknesses and margin preparation designs. The aim of this study was to provide mechanical research evidence and a reference for exploring standardized clinical protocols for the design of occlusal veneer restorations of maxillary first molars.MethodA 3Shape (Intraoral Scanner) was used to scan the maxillary first molar teeth in vitro, after which 3D printing was carried out. Three different edge designs were applied to identical teeth: straight-beveled finishing line(SFL), chamfer finishing line(CFL), and standard cuspal inclination(SCI). Preparation was carried out with a thickness of 0.5 mm. Using the surface deformation feature, the occlusal veneer was thickened to 0.5 mm and 1.0 mm, and periodontal ligaments were added. They were then placed into the upper and lower jaws and dental arches. Finite element analysis was performed after applying bite force dispersion to the loading area on the mandible following dynamic contact.Results(1) As the thickness increased, the maximum Von Mises stress in the occlusal veneers SFL and CFL also increased, while the SCI exhibited the opposite trend. (2). The trend of the maximum Von Mises stress in the adhesive layer decrease gradually with increasing thickness of the occlusal veneer. The stresses of the SFL and CFL is concentrated primarily at the edge position below the functional cusp, resulting in relatively low adhesive stress. However, in the SCI group, the maximum stress at the edge of the adhesive layer exceeds the maximum shear strength of commonly used adhesives.ConclusionsUnder the experimental conditions, the mechanical properties of the maximum Von Mises stress in the SFL, CFL, and SCI occlusal veneers meet clinical needs. Incorporating the minimally invasive concept of tooth preservation, a thickness of 1.0 mm are optimal for glass ceramic occlusal veneers on maxillary first molars.

Elucidating Phosphate and Cadmium Cosorption Mechanisms on Mineral Surfaces with Direct Spectroscopic and Modeling Evidence.

The simultaneous sorption of cations and anions at the mineral-water interface can substantially alter their individual sorption characteristics; however, this phenomenon lacks a mechanistic understanding. Our study provides direct spectroscopic and modeling evidence of the molecular cosorption mechanisms of the cadmium ion (Cd2+) and phosphate (P) on goethite and layered manganese (Mn) oxide of birnessite, through in situ attenuated total reflection Fourier-transform infrared (ATR-FTIR), P K-edge X-ray absorption near-edge structure (XANES) spectroscopy, and surface complexation modeling. Phosphate synergistically cosorbed with Cd on goethite predominantly through P-bridged ternary complexes (≡Fe-P-Cd) and electrostatic interactions at wide pH conditions. Likewise, P and Cd exhibited synergistic cosorption on birnessite by forming P-bridged ternary complexes (≡Mn-P-Cd) and weak competitive sorption at the layer edge sites. As pH and Cd loading increased, the surface P species transitioned from a binary complex to a ternary complex and/or Cd3(PO4)2 precipitate for both goethite and birnessite. Compared to that in solution at pH 8, the formation of Cd3(PO4)2 was inhibited by the presence of goethite and birnessite, ascribed to the specific adsorption of P and Cd, more pronounced in birnessite due to the stronger sorption of Cd at its vacant sites. The discovered cosorption mechanisms of P and Cd have important implications for understanding and predicting their mobility and availability in Cd-contaminated settings.

The impact of finite span and wing-tip vortices on a turbulent NACA0012 wing

High-fidelity simulations are conducted to investigate the turbulent boundary layers around a finite-span NACA0012 wing with a rounded wing-tip geometry at a chord-based Reynolds number of $Re_c=200\,000$ and at various angles of attack up to $10^\circ$ . The study aims to discern the differences between the boundary layers on the finite-span wing and those on infinite-span wings at equivalent angles of attack. The finite-span boundary layers exhibit: (i) an altered streamwise and a non-zero spanwise pressure gradient as a result of the variable downwash induced by the wing-tip vortices (an inviscid effect typical of finite-span wings); (ii) differences in the flow history at different wall-normal distances, caused by the variable flow angle in the wall-normal direction (due to constant pressure gradients and variable momentum normal to the wall); (iii) laminar flow entrainment into the turbulent boundary layers near the wing tip (due to a laminar–turbulent interface); and (iv) variations in boundary layer thickness across the span, attributed to the variable wall-normal velocity in that direction (a primarily inviscid effect). These physical effects are then used to explain the differences in the Reynolds stress profiles and other boundary layer quantities, including the reduced near-wall peak of the streamwise Reynolds stress and the elevated Reynolds stress levels near the boundary layer edge, both observed in the finite-span wings. Other aspects of the flow, such as the downstream development of wing-tip vortices and their interactions with the surrounding flow, are reserved for future investigations.

Mixing enhancement assisted by dual plate cavity in supersonic flow

Fast and efficient mixing of high-speed shear flow formed by fuel and oxidizer is of great importance for the improvement of rocket-based combined cycle engine performance. Nevertheless, the existence of compressibility effects of high-speed flow significantly inhibits the growth process of a mixing layer. Moreover, a finite-length combustor of the engine calls for more effective enhanced-mixing strategies to complete mixing in a shorter streamwise distance. To this end, in present paper, the strategy called dual plate cavity (DPC) is proposed to promote mixing. Three cases including the benchmark, front-DPC and back-DPC cases are selected to perform the comparative study. By means of high-order direct numerical simulations, the structure evolution characteristics and turbulence intensity distributions are researched. The index of velocity thickness is utilized to assess the mixing layer growth. The results indicate that with the introduction of DPC, the mixing process is dramatically promoted. The penetration behavior of newly found T-shaped structures into the upper main stream can engulf more fluid into the mixing region. Specifically, in the back-DPC case, the coexistence of both large-scale and small-scale structures in the far flow field can improve the turbulence intensity. The spatial correlation analysis results show that with the influence of DPC, the structure sizes are much larger than that of the benchmark case in the same streamwise position. Meanwhile, the contour line equal to 0.5 possesses property of distortion for the back-DPC case. The drastic pulsation of a mixing layer edge can obviously promote the mixing process. Through exploration of the enhanced-mixing mechanisms, this work indicates that the proposed DPC strategy is a good candidate for efficient mixing, and in the future, more detailed work including three-dimensional simulations concerning the strategy optimization is suggested to be performed.

Unveiling the competitive mechanism between SO2 and PCDD/Fs on activated carbon adsorption

In municipal solid waste incineration (MSWI) plants, activated carbon (AC) adsorption is the key technique for eliminating Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) from flue gases. This research thoroughly investigates the potential competitive adsorption between SO2 and PCDD/Fs and examines how adsorption at the center and the edge of the AC layer impacts the adsorption process. The findings show a decline in the removal efficiency of PCDD/Fs from 86.8 % to 84.2 % and further to 74.4 % when using SO2 pre-treated (AC-A3) and H2SO4-impregnated (AC-B2) activated carbon, respectively. Multiple characterization methods reveal that sulfur elements occupy active sites within the inner pores of the activated carbon, reducing the availability of its pore structure, particularly affecting microporous more than mesoporous structures. DFT calculations suggest that the π-π EDA effect facilitates the adsorption of 2,3,7,8-Tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD), whereas dispersion force drive SO2 adsorption. Comparisons among various oxygenated functional groups show that the organic acid anhydride (CO-CO) has better adsorption selectivity toward TCDD and less adsorption to SO2. This study provides a novel perspective on the adsorption mechanisms of PCDD/Fs on AC and the competitive dynamics of sulfur in the flue gas.

Benign Lobular Inner Nuclear Layer Proliferations of the retina.

Report the clinical and imaging findings of a patient with an intraretinal benign tumor that was documented as an unexpected clinical finding after an ischemic stroke in the context of mitral valve disease. This tumor must be distinguished from retinoblastoma and other malignant neoplasms. A patient with intraretinal tumor of the inner nuclear layer (INL) underwent a combination of ophthalmic examination, fundus photography, fluorescein angiography, optical coherence tomography (OCT), and optical coherence tomography angiography (OCT-A). A 64-year-old male patient with unilateral benign tumor lesions dependent on the internal retina, centered in the posterior pole, and multifocal. OCT showed that these lesions were centered within the INL at the edge of the inner plexiform layer and were not associated with other findings in the posterior pole. Benign Lobular Inner Nuclear Layer Proliferations (BLIP) of the Retina are recently described lesions that should be considered, given their distinctive characteristics that set them apart from other benign and malignant retinal lesions.

793. MODIFIED HELLER DOR FOR ACHALASIA

Abstract Introduction Achalasia is an esophageal disorder that involves a failure in the relaxation of the lower esophageal sphincter, which leads to dysphagia and other symptoms. The objective of the present study is to report the surgical technique performed in a patient with achalasia, in which the Heller myotomy technique was performed together with Dor fundoplication. Method The technique performed was a modified Heller-Dor with long myotomy Surgical intervention began with the introduction of the trocars plus pneumoperitoneum, a narrow of distal esohagus and enlargement of the diaphragmatic crura, mas found. Continuing with dissection of the esophageal hiatus with ultrasonic forceps, release of phreno-esophageal membrane. The esophagus was elongated in the mediastinum and brought 7 centimeters to the abdomen. After that, there was approximation of the diaphragmatic crura with 1 point of Ethibond 2-0. Following the dissection of the eophagogastric junction and identification of the posterior and anterior vagus nerve, releasing the “fat pad” for correct identification of the esophagogastric junction. So, the myotomy in the esophagus 6 centimeters above the cardia and 3 centimeters below, was performed. Follow, the gastric fundus was sutured to the anterior border of the esophagus and left diaphragmatic pillar with 2-0 Ethibond, until the esophagus gastric junction in running suture. The anterior suture, covering the myotomy the edge of the muscular layer of the esophagus as the same way. Conclusion Finally, with regard to the treatment of achalasia, Heller cardiomyotomy plus Dor fundoplication, has been shown to be efficient for improvement of dysphagia symptoms and to avoid symptoms related to emergence of reflux after myotomy. https://drive.google.com/file/d/176L7Jo0tFMylWvhsgtscESHHFbOONl4A/view?usp=sharing

Improved Wall Function Method for Hypersonic Reacting Turbulent Boundary Layers

The chemical reaction and cold wall effects in hypersonic reacting turbulent boundary layers (HRTBLs) cause the failure of the existing wall function method. Therefore, this paper proposes an improved wall function method to simulate skin friction cf and wall heat flux qw in HRTBLs accurately and efficiently. Firstly, the temperature–velocity relation is extended to a generalized enthalpy–velocity relation to comprehensively involve the chemical reaction and cold wall effects. Then, a new unified velocity law of the wall for the inner layer of HRTBLs is theoretically derived. Finally, an improved wall function method is designed with the new laws of the wall. Numerical experiments of typical HRTBLs show that, compared with the existing wall function method, the improved wall function method can significantly reduce the errors of cf and qw from 8.0% and 10.2% to 0.4% and 0.5%, respectively, when the near-wall grids are relaxed to the viscous sublayer, while from 11.0% and 15.3% to 1.2% and 5.8%, respectively, when the near-wall grids are further relaxed to the logarithmic layer, bringing 2.7 and 15 times enhancement of the simulation efficiency. Moreover, by introducing the reference point, the improved wall function method removes the boundary layer edge quantities while ensuring accurate results.

Innovative computed tomography based mapping of the surgical posterior tympanotomy: An exploratory study

Robotic devices have recently enhanced cochlear implantation by improving precision resulting in reduced intracochlear damage during electrode insertion. This study aimed to gain first insights into the expected dimensions of the cone-like workspace from the posterior tympanotomy towards the round window membrane.This retrospective chart review analyzed ten postoperative CT scans of adult patients who were implanted with a CI in the past ten years. The dimensions of the cone-like workspace were determined using four landmarks (P1–P4). In the anteroposterior range, P1 and P2 were defined on the edge of the bony layer over the facial nerve and chorda tympani nerve, respectively. In the inferosuperior range, P3 was defined on the bony edge of the incus buttress and P4 was obtained at a distance of 0.45 mm between the facial nerve and the chorda tympani nerve. After selecting the landmarks, the calculations of the dimensions of the surgical access space were done in a standardized coordinate system and presented using descriptive statistics.The cone-like space is limited by two maximal angles, α and β. The average angle α of 19.84 (±3.55) degrees defines the angle towards the round window membrane between P1 and P2. The second average angle β of 53.56 (±10.29) degrees defines the angle towards the round window membrane between P3 and P4. Based on the angles the mean anteroposterior range of 2.25 (±0.42) mm and mean inferosuperior range of 6.73 (±2.42) mm. The distance from the posterior tympanotomy to the round window membrane was estimated at 6.05 (±0.71) mm.These findings present data on the hypothetical maximum workspace in which a future robotically steered insertion tool can be positioned for an optimal automated electrode insertion. A larger sample size is necessary before generalizing these dimensions to a population. Further research including preoperative CT scans is needed for planning robotic-steered cochlear implantation.

Mean-flow structures of the turbulent boundary layers bounding a two-dimensional separation bubble

Understanding the mean-flow structures of a separated turbulent boundary layer (TBL) is crucial for turbulence modeling. This study investigates the spatial scaling properties of the total shear stress and mixing length in the TBLs bounding a two-dimensional (2D) separation bubble, aiming to derive analytical descriptions for the entire mean-velocity profiles of the TBLs. For the adverse pressure gradient (APG) TBL upstream of the separation bubble, the total shear stress possesses a two-layer structure with an inner layer adhering to a linear law and an outer layer conforming to a defect power law. In contrast, the mixing length profile consists of four layers, namely the viscous sublayer, the buffer layer, the overlap layer, and the wake region. Each of the layers exhibits a power law or a defect power law relationship with the spatial coordinate normal to the wall. In the four-layer structure, three parameters are sensitive to the variation of the APG: the buffer-layer thickness, the relative magnitude of the mixing length at the boundary layer edge, and a defect power law exponent quantifying the extent of the wake region. For the reattached TBL downstream of the separation bubble, the total shear stress consists of two parts. One part is induced by the pressure gradient and retains the two-layer structure, while the other, engendered by the intense turbulence advected from the separated shear layer, exhibits a dual-power-law distribution. The advected turbulence also significantly alters the four-layer structure of the mixing length, resulting in an augmented buffer layer, a diminished overlap layer, and a wake region that mimics a turbulent mixing layer. Via a dilation ansatz to describe the scaling transition between adjacent layers, the study formulates the complete profiles of the total shear stress and mixing length. The formulation leads to the derivation of novel analytical expressions for the entire mean-velocity profiles of the TBLs. The expressions are in precise accord with the direct numerical simulations of an incompressible 2D separation-bubble flow and a 2D impinging shock wave/TBL interaction. The elucidation of the mean-flow structures through this study is anticipated to facilitate the analysis of turbulence models, thereby enhancing their performance in simulating separated TBLs. The construction of the mean-flow descriptions by inspecting the spatial scaling properties of turbulence paves a promising way for theoretical exploration of complex nonequilibrium TBLs.

On Graphs Embeddable in a Layer of a Hypercube and Their Extremal Numbers

A graph is cubical if it is a subgraph of a hypercube. For a cubical graph H and a hypercube Qn\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$Q_n$$\\end{document}, ex(Qn,H)\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\ extrm{ex}(Q_n, H)$$\\end{document} is the largest number of edges in an H-free subgraph of Qn\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$Q_n$$\\end{document}. If ex(Qn,H)\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\ extrm{ex}(Q_n, H)$$\\end{document} is at least a positive proportion of the number of edges in Qn\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$Q_n$$\\end{document}, then H is said to have positive Turán density in the hypercube; otherwise it has zero Turán density. Determining ex(Qn,H)\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\ extrm{ex}(Q_n, H)$$\\end{document} and even identifying whether H has positive or zero Turán density remains a widely open question for general H. In this paper we focus on layered graphs, i.e., graphs that are contained in an edge layer of some hypercube. Graphs H that are not layered have positive Turán density because one can form an H-free subgraph of Qn\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$Q_n$$\\end{document} consisting of edges of every other layer. For example, a 4-cycle is not layered and has positive Turán density. However, in general, it is not obvious what properties layered graphs have. We give a characterization of layered graphs in terms of edge-colorings. We show that most non-trivial subdivisions have zero Turán density, extending known results on zero Turán density of even cycles of length at least 12 and of length 8. However, we prove that there are cubical graphs of girth 8 that are not layered and thus having positive Turán density. The cycle of length 10 remains the only cycle for which it is not known whether its Turán density is positive or not. We prove that ex(Qn,C10)=Ω(n2n/logan)\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\ extrm{ex}(Q_n, C_{10})= \\Omega (n2^n/ \\log ^a n)$$\\end{document}, for a constant a, showing that the extremal number for a 10-cycle behaves differently from any other cycle of zero Turán density.

Cadmium Isotope Fractionation during Adsorption onto Edge Sites and Vacancies in Phyllomanganate.

Cadmium (Cd) geochemical behavior is strongly influenced by its adsorption onto natural phyllomanganates, which contain both layer edge sites and vacancies; however, Cd isotope fractionation mechanisms at these sites have not yet been addressed. In the present work, Cd isotope fractionation during adsorption onto hexagonal (containing both types of sites) and triclinic birnessite (almost only edge sites) was investigated using a combination of batch adsorption experiments, extended X-ray absorption fine structure (EXAFS) spectroscopy, surface complexation modeling, and density functional theory (DFT) calculations. Light Cd isotopes are preferentially enriched on solid surfaces, and the isotope fractionation induced by Cd2+ adsorption on edge sites (Δ114/110Cdedge-solution = -1.54 ± 0.11‰) is smaller than that on vacancies (Δ114/110Cdvacancy-solution = -0.71 ± 0.21‰), independent of surface coverage or pH. Both Cd K-edge EXAFS and DFT results indicate the formation of double corner-sharing complexes on layer edge sites and mainly triple cornering-sharing complexes on vacancies. The distortion of both complexes results in the negative isotope fractionation onto the solids, and the slightly longer first Cd-O distances and a smaller number of nearest Mn atoms around Cd at edge sites probably account for the larger fractionation magnitude compared to that of vacancies. These results provide deep insights into Cd isotope fractionation mechanisms during interactions with phyllomanganates.

Coal-based graphene formation by CO2 laser scribing: Various structures and excellent electrochemical performance

The laser-induced technique is a cost-effective and environmentally-friendly method for upgrading coal into high value-added graphene materials. Here, laser-induced graphenes (LIGs) were prepared from different rank coals in one-step under vacuum conditions using a designed CO2 infrared laser device. The characteristics of laser-induced products were studied by X-ray diffraction, X-ray photoelectron spectroscopy, Raman spectroscopy, scanning electron microscopy, and high-resolution transmission electron microscopy. The electrochemical characteristics of coal-based laser-induced graphenes (C-LIGs) were examined in a three-electrode test system. Results show that subbituminous coal, bituminous coal, and low-metamorphic anthracite can form LIG with fewer layers after laser irradiation. The morphology of C-LIG is a layered porous structure. Corrugated folds can be observed at the edges of the C-LIG layer. There are only a few layers of graphene, with the majority of them concentrated in 2–10 layers. The most interesting result is that LIG prepared from low volatile bituminous coal has the highest crystallinity, the largest aromatic layer size, and the lowest average graphene layer number. Furthermore, LIG made from low volatile bituminous coal (LIG-ZJ) exhibits excellent electrical double-layer capacitive behavior, low equivalent series resistance (3.73 Ω), good rate capability, excellent cycling stability, greater Coulombic efficiency, and high mass specific capacitance. The LIG-ZJ electrode exhibits a high specific capacitance of 1879.92 F/g at 1 A/g, which is nearly ten times greater than that of most activated carbon electrodes reported. In addition, its power density and energy density can reach up to 924.07 kW/kg and 217.11 Wh/kg. These results indicate that coal-based laser-induced graphene has significant potential for application in the field of electrochemical energy storage.

Screening, characterization and mechanism of a potential stabiliser for nisin nanoliposomes with high encapsulation efficiency

The encapsulation efficiency (EE%) reflects the amount of bioactive components that can be loaded into nanoliposomes. Obtaining a suitable nanoliposome stabiliser may be the key to improving their EE%. In this study, three polyphenols were screened as stabilisers of nanoliposomes with high nisin EE%, with curcumin nanoliposomes (Cu-NLs) exhibiting the best performance (EE% = 95.94%). Characterizations of particle size, PDI and zeta potential indicate that the Cu-NLs had good uniformity and stability. TEM found that nisin accumulated at the edges of the Cu-NLs' phospholipid layer. DSC and FT-IR revealed that curcumin was involved in the formation of the phospholipid layer and altered its structure. FT-IR and molecular docking simulations indicate that the interactions between curcumin and nisin are mainly hydrogen bonding and hydrophobic. In whole milk, Cu-NLs effectively protected nisin activity. This study provides an effective strategy for improving the EE% of nanoliposomes loaded with nisin and other bacteriocins.

Study on deformation and failure characteristics of oblique-cut locked rock slope under rainfall conditions

Based on the disaster-pregnant environment and development characteristics of landslide disasters in the western region of Henan Province, a generalized model was established by taking the “oblique-cut” locking rock slope in the layered rock slope as the research object. The numerical simulation method was used to analyze the deformation and failure mechanism and stability influence law of the oblique-cut locking rock slope in western Henan under rainfall conditions. The results show that the inclination angle of the weak interlayer directly affects the deformation and failure characteristics of the slope rock mass. With the increase of the geometric parameters of the slope and the inclination angle of the weak interlayer, the failure mechanism is manifested as the slip shear failure along the level at the foot of the slope → the slip shear failure along the level at the foot of the slope (the sliding surface moves upward) → the shear failure in the middle of the slope surface → the slip shear failure along the level at the foot of the slope (the sliding surface moves downward) → the uplift shear failure at the lower edge of the rock layer. When the dip angle of the weak interlayer is constant, the slope stability decreases gradually with the increase in slope gradient and slope height, and the geometric factors of the slope control the overall change trend of the slope stability coefficient. When the slope is greater than 55° and the slope height is greater than 55 m, the shear stress of the slope locking section exceeds its shear strength, and the probability of landslide instability is greatly increased.

Influence of tantalum addition on the microstructure and wear resistance properties of NiCuBSi/65WC composite coatings

Nickel-based tungsten carbide composite coatings are extensively utilized on various wear-resistant workpiece surfaces due to their exceptional properties, including high hardness and wear resistance. However, as the WC content increases, uneven structure and susceptibility to cracking of the coating during the forming process are enhanced, thereby impacting its service performance. To address these issues, NiCuBSi/65WC composite coatings with varying tantalum (Ta) contents were fabricated on 42CrMo steel substrates by laser cladding. The influence mechanism of Ta content on the microstructure and wear resistance of the coatings was investigated. The results demonstrate that the addition of tantalum promotes the formation of reinforcement phases such as TaC and W2C in the coating. Moreover, with increased Ta content, the edge of WC particle reaction layers in the coating gradually transforms from sawtooth to shorter rod-shaped morphology. Additionally, as the Ta content increases, the dissolution degree of WC particles rises, thereby facilitating the formation of TaC and W2C compound carbide. This leads to an enhancement in both the quantity and uniform distribution of carbide reinforced phases within the coating, resulting in an increase in average coating hardness from 482.4 HV0.2 to 580.1 HV0.2. When the Ta content reaches 7 wt% in particular, no cracks are observed on the coating surface, and a uniform distribution of carbides is achieved. The relative wear resistance of NiCuBSi/65WC coating with 7 wt% Ta is approximately 2.36 times higher than that without Ta.

Experimental research and optimization based on response surface methodology on machining characteristics of cast Al-7Si-0.6 Mg alloy: Effects of cutting parameters and heat treatment

In this study, structural, mechanical and machining features of Al-7Si-0.6 Mg alloy manufactured by permanent mold casting (PMC) in both as-cast (AC) and T6 heat-treated (HT) conditions were investigated. Structural and mechanical properties were determined using conventional methods. Milling experiments were conducted with titanium aluminum nitride (TiAlN) coated carbide end mills in CNC milling machine under conditions of three different cutting speeds (V: 50, 80 and 110 m/min), feed rate (f: 0.08; 0.16 and 0.24 mm/rev) and constant depth of cut (DoC) (1.5 mm). It was seen that structure of AC Al-7Si-0.6 Mg comprised of aluminum-rich α-Al, coral-like eutectic Al-Si, primary Si, Mg2Si, Fe-rich plate, acicular β-Fe (β-Al5FeSi) and script-like π-Fe (π-AlSiMgFe) intermetallic phases. Eutectic Al-Si, primary Si, β-Fe and π-Fe phases in the structure of the alloy in the HT condition were partially dissolved and turned into an agglomerated and spherical state. While the hardness (HB), yield (YS) and tensile strength (TS) of the alloy raised with HT, the elongation to fracture (EF) reduced. While cutting force (CF), surface roughness (SR), built-up layer (BUL) and built-up edge (BUE) decreased with increasing V, they increased with increasing f in the milling of both cast and HT alloys. Adhered layers and feed marks were consisted of the cutted surfaces of the alloys. While the most adhered layer was observed in AC alloys at a low V (50 m/min) and high f (0.24 mm/rev) combination, the least adhered layer formation was observed at the highest V and the lowest f value in HT alloys. Optimum parameters with Response Surface Methodology (RSM) were determined as V: 125 m/min and f: 0.04 mm/rev in AC and HT cases. The statistical significance of V and f on CF and SR was revealed by analysis of variance (ANOVA), while mathematical models were improved to predict CF and SR.