Three-dimensional Mesh Research Articles

Abstract TP299: The Relationship Between Intracranial Arterial Stenosis Rate and Cerebral Perfusion

Background and and Objectives: The pressure ratio (PR) across lesions is a vital indicator for assessing residual blood flow after stenosis, yet the relationship between symptomatic intracranial atherosclerotic stenosis degrees and cross-lesion pressure ratios remains unclear. Methods: Data were derived from the Chinese National Stroke Registry III (CNSR III). Three-dimensional meshes were constructed based on TOF-MRA using the finite element method controlled by the Navier-Stokes equation to obtain pressure values. PR was calculated as the ratio of proximal to distal pressure at the stenosis site, indicating post-stenosis blood flow. PR > 0.76 meant normal pressure ratio, while PR ≤ 0.76 indicated reduced ratio. Arterial stenosis severity was categorized using the WASID Method: 50%-69% for moderate and 70%-99% for severe. Statistical analysis explored the correlation between stenosis severity and low PR. Results: The study included 438 patients with symptomatic intracranial arterial stenosis (50-99%), median age 64, 33.79% female. PR ≤ 0.76 accounted for 30%. Among them, PR ≤ 0.76 was observed in 26% of moderate stenosis (50-69%) patients and 39% of severe stenosis (70-99%) patients (Figure A). The PR ≤ 0.76 frequency was significantly higher in severe compared to moderate stenosis (P=0.01). For anterior (Figure B) and posterior (Figure C) circulation stenosis, PR ≤ 0.76 accounted for 43% and 22% respectively, more prevalent in severe stenosis (P=0.01 and P=0.61, respectively). Conclusion: Most patients with symptomatic intracranial atherosclerotic stenosis exhibit normal PR levels, with a correlation between arterial stenosis and cross-lesion pressure ratio. Further research is needed to determine if PR is a more suitable criterion than arterial stenosis for selecting patients for stent treatment.

Multi-Physics Three-Dimensional Component Placement and Routing Optimization Using Geometric Projection

Abstract This article presents a novel three-dimensional topology optimization framework developed for 3D spatial packaging of interconnected systems using a geometric projection method (GPM). The proposed gradient-based topology optimization method simultaneously optimizes the locations and orientations of system components (or devices) and lengths, diameters, and trajectories of interconnects to reduce the overall system volume within the prescribed 3D design domain. The optimization is subject to geometric and physics-based constraints dictated by various system specifications, suited for a wide range of transportation (aerospace or automotive), heating, ventilation, air-conditioning, and refrigeration, and other complex system applications. The system components and interconnects are represented using 3D parametric shapes such as cubes, cuboids, and cylinders. These objects are then projected onto a three-dimensional finite element mesh using the geometric projection method. Sensitivities are calculated for the objective function (bounding box volume) with various geometric and physics-based (thermal and hydraulic) constraints. Several case studies were performed with different component counts, interconnection topologies, and system boundary conditions and are presented to exhibit the capabilities of the proposed 3D multi-physics spatial packaging optimization framework.

Effect of high humidity on the initial mechanical properties and failure modes of thin spray-on liners (TSLs)

Thin Spray-on Liners (TSLs) are a novel rock support technology used in underground projects, which often encounter harsh environments such as high humidity. The mechanical properties of TSLs are affected by the high humidity environment. This study aims to summarize the support mechanisms of TSLs and evaluate the effects of humidity on their performance. Two cement-based TSLs were prepared. They used vinyl acetate-ethylene copolymer emulsion (VAE emulsion) and polyacrylate emulsion as modifying materials, respectively. Specimens were subjected to four different humidity environments for 7 days. The mechanical properties of the specimens were evaluated through compressive, flexural and pull-out tests. The impermeability test was utilized to test the sealing of TSLs. Microscopic observation was conducted using a Lecia microscope. The study also analyzed the interfacial failure modes observed in the pull-out test. The results indicated that increasing humidity hindered the film formation reaction of TSLs, preventing the formation of a continuous three-dimensional spatial polymer mesh structure. Instead, cohesive large particles were formed, negatively impacting the mechanical properties. Additionally, increasing humidity led to the formation of large pores and crack lines within TSLs, further decreasing their mechanical and sealing properties. The increase in humidity also weakened the dry shrinkage effect of TSLs, resulting in increased bond strength. Therefore, analyzing the initial mechanical properties of TSLs under high humidity conditions is crucial for guiding their application in underground projects.

The Slump Flow of Cementitious Pastes: Simulation vs. Experiments.

Understanding the transient properties of cementitious pastes is crucial for construction materials engineering. Computational modeling, particularly through Computational Fluid Dynamics (CFD), offers a promising avenue to enhance our understanding of these properties. However, there are several numerical uncertainties that affect the accuracy of the simulations using CFD. This study focuses on evaluating the accuracy of CFD simulations in replicating slump flow tests for cementitious pastes by determining the impact of the numerical setup on the simulation accuracy and evaluates the transient, viscosity-dependent flows for different viscous pastes. Rheological input parameters were sourced from rheometric tests and Herschel-Bulkley regression of flow curves. We assessed spatial and temporal convergence and compared two regularization methods for the rheological model. Our findings reveal that temporal and spatial refinements significantly affected the final test results. Adjustments in simulation setups effectively reduced computational errors to less than four percent compared to experimental outcomes. The Papanastasiou regularization was found to be more accurate than the bi-viscosity model. Employing a slice geometry, rather than a full three-dimensional cone mesh, led to accurate results with decreased computational costs. The analysis of transient flow properties revealed the effect of the paste viscosity on the time- and shear-dependent flow progress. The study provides an enhanced understanding of transient flow patterns in cementitious pastes and presents a refined CFD model for simulating slump flow tests. These advancements contribute to improving the accuracy and efficiency of computational analyses in the field of cement and concrete flow, offering a benchmark for prospective analysis of transient flow cases.

Electron beam irradiation induced aggregation, structural and functional changes of soybean 11S globulin

This study investigated the effects of different irradiation doses of an electron beam (e-beam) (0, 2, 4, 6, 8, and 10 kGy) on the structure, emulsification, foaming, and rheological and gel properties of soybean 11S globulin. The irradiation treatment at 4 and 6 kGy significantly increased the solubility, surface hydrophobicity, disulfide bonding, and ζ-potential of 11S globulin, decreased the particle size of the protein solution, and effectively improved the emulsifying activity and foaming stability of the protein solution. Moreover, irradiation induced moderate cross-linking and aggregation of the proteins, thereby increasing the apparent viscosity and shear stress of the protein solution. In addition, the low-field NMR and microstructure analysis results revealed that protein gels formed a dense and homogeneous three-dimensional mesh structure after irradiation (6 kGy), along with increased content of bound water (T2b) and water not readily flowable (T21) and a decrease content of free water (T22). Overall, our results confirmed that e-beam irradiation could significantly improve the physicochemical properties of soybean 11S globulin. Our study thus provides a new technical means for the application of electron beam irradiation technology toward protein modification and broadens the high-value utilization of soybean 11S globulin in the food processing industry.

Formation of Three-Dimensional Polysuccinimide Electrospun Fiber Meshes Induced by the Combination of CaCl2 and Humidity.

Even though electrospinning is getting more and more attention, the preparation of 3D nanofibrous meshes is still a big challenge that limits the application of electrospun materials, especially in tissue engineering. To overcome this problem, several solutions are introduced but most of them focus on the postprocessing of the electrospun meshes. This paper presents a straightforward novel method that utilizes the joint effect of the addition of CaCl2 and the relative environmental humidity (RH), which can induce the random 3D formation of polysuccinimide (PSI) electrospun fibers with different such as wrinkled or ribbon-like structures. Although the effect of humidity and inorganic salt additives on the micro and macrostructure of electrospun fibers is known, the connection between the two in this manner has never been presented. To investigate the effect, fibers with different PSI and CaCl2 concentrations at different humidity RH levels are prepared, and their microstructure is visualized with high-resolution scanning electron microscopy (SEM). To reveal the nature of the interaction between the polymer and the CaCl2, Fourier-transformed infrared (FTIR), X-ray diffraction (XRD), and thermogravimetry (TGA) measurements are carried out and 3D nanofibrous structures are obtained.

Three-dimensional titanium mesh-based flow electrode capacitive deionization for salt separation and enrichment in high salinity water

Flow electrode capacitive deionization (FCDI) is a highly promising desalination technique known for its exceptional electrosorption capacity, making it suitable for efficient salt separation in high salinity water. However, the unsatisfactory charge transfer process between the flow electrode and current collector severely curtails the salt separation and enrichment performance of the FCDI device. To address this issue, three-dimensional titanium mesh (3D-TM) was proposed as a novel current collector for FCDI device, which significantly amplifies the charge transfer area and exhibits excellent salt separation performance. The 3D-TM current collector promotes the electron transfer, charge percolation, and ion migration processes through the electroconvection generated by the turbulence effect on the flow electrode. In the specific case of the 20-mesh 3D-TM, which is composed of 12 stacking layers of titanium mesh, the remarkable average salt removal rate and charge efficiency were achieved 5.06 μmol cm−2 min−1 and 92.9 % under an appropriate applied voltage of 2.0 V, respectively. Dramatically, the desalination performance maintained above 76.4 % over 100 desalination cycles at 2.0 V, demonstrating the exceptional cyclic stability of the 3D-TM FCDI cell. In the seawater desalination, the 3D-TM FCDI cell exhibited an impressive salt removal efficiency of 97.5 % (from 34.2 g L−1 to 0.84 g L−1) for 1 L East China seawater at 2.0 V for 24 h. For lithium-ion enrichment, the FCDI continuous desalting system achieved an astonishing concentration of 17.3 g L−1 for Li+ ions enrichment from an initial concentration of 1.30 g L−1, obtaining the average salt treating rate of 23.6 g m−2h−1 and charge efficiency of 80.0 %. Moreover, the lithium-sodium ions and lithium-magnesium ions enrichments were both conducted, yielding an enriched concentration of 10.4 g L−1 and 7.30 g L−1 for Li+ ions, respectively. These findings highlight the enormous potential of FCDI technology in industrial engineering applications, further establishing it as a highly viable solution.

Antimicrobial peptide-modified AIE visual composite wound dressing for promoting rapid healing of infected wounds.

Wound infection is a major problem faced during wound healing. Therefore, it is necessary to develop wound dressings with excellent antimicrobial properties. Here, a smart response system of PVA-TPE/HA-AMP/SF/ALG wound dressing was prepared by a combination of chemical cross-linking and freeze-drying methods. We grafted AMP onto HA to endow the wound dressing with bacterial resistance and slow release of AMP. At the same time, the system detects bacterial activity in real time for precise antimicrobial activity (through the use of PVA-TPE) and modulates inflammation to reduce bacterial infection (through the use of AMP). In addition, the PVA-TPE/HA-AMP/SF/ALG wound dressing has a good three-dimensional mesh structure, which promotes cell proliferation, enhances collagen deposition and angiogenesis, and thus effectively promotes rapid healing of infected wounds. Moreover, it can induce the expression of inflammatory factors such as VEGF, TNF-α, IFN-γ, IL-4 and TGF-β1 in infected wounds through the Wnt/CAMK/p-PKC signaling pathway, inhibit inflammatory responses, promote wound healing and reduce scar formation. Therefore, the PVA-TPE/HA-AMP/SF/ALG wound dressing smart response system shows great promise in infected wound healing.

Investigation the thermal performance of Nano-Enhanced Phase Change Material (NEPCM) in an enclosure

Phase change materials (PCMs) play a vital role in thermal energy storage applications, as they provide efficient and dependable heat storage and release capabilities. This study provides a comprehensive evaluation of the thermal performance of Nano-Enhanced Phase Change Material (NEPCM) in an enclosure, with a focus on the effect of temperature variation and the role of nanoparticles. Variable temperature regimes significantly influence the physical and thermal properties of the NEPCM, as revealed by numerical simulations. The enthalpy-porosity approach for the phase change process and the solution of the Navier-Stokes equations for fluid flow serve as the primary foundations for the numerical model that will be covered in this study. With only a single phase of user input, ANSYS facilitates the creation of three-dimensional models and solid geometry meshes. Notably, an increase in the temperature of the heat-supplying wall resulted in substantial changes to the NEPCM, which we have thoroughly investigated and quantified. It has been demonstrated that the incorporation of various nanoparticles (Al2O3, CuO, and ZnO) into paraffin enhances the heating process, thereby enhancing the thermal conductivity, heat transfer coefficient, and surface tension of the NEPCM. The three nanoparticles decrease the mass fraction of paraffin in the range of 0.00 to 0.960 at the same concentration and testing temperature. In addition, increasing nanoparticle concentration under higher temperature regimes resulted in a faster and more uniform nanoparticle synthesis, significantly enhancing the NEPCM's thermal performance. Particularly, as the temperature increased, the NEPCM near the wall melted more rapidly. The study reveals the crucial role that temperature plays in modulating the behavior and performance of NEPCM, thereby providing valuable insights for thermal management systems. These results demonstrate the significance of temperature control for maximizing the potential of NEPCM in a variety of applications. As the temperature rises, one side becomes covered in the blue color (solid), while in the standard case, the melting curve shows a little red region (melting) at the other side that starts to increase when the nanomaterial's are added.

Spatially-assembled binary carbon anode synergizing directional electron transfer and enriched microbe accommodation for wastewater treatment and energy conversion: From simulation to experiments

Bioelectrochemical systems (BESs) hold prospects in wastewater energy and resource recovery. Anode optimization is important for simultaneous enhancement of wastewater energy conversion and effluent quality in BESs. In this study, a multi-physics model coupling fluid flow, organic degradation and electrochemical process was constructed to guide the design and optimization of BES anodes. Based on the multi-physics simulation, spatially-assembled binary carbon anodes composed of three-dimensional carbon mesh skeleton and granular activated carbon were proposed and established. The granular activated carbon conducive to microbe accommodation played a vital role in improving effluent water quality, while the carbon mesh skeleton favoring electron collection and transfer could enhance the bioelectricity output. With an average chemical oxygen demand (COD) removal rate of 0.442 kg m−3 d−1, a maximum power density of 20.6 W m−3 was achieved in the optimized composite anode BES, which was 25% and 154% higher than carbon mesh skeleton BES and granular activated carbon BES. Electroactive bacteria were enriched in composite anodes and performed important functions related to microbial metabolism and energy production. The spatially-assembled binary carbon anode with low carbon mesh packing density was more cost-effective with a daily energy output per anode cost of 221 J d−1 RMB−1. This study not only provides a cost-efficient alternative anode to simultaneously improve organic degradation and power generation performance, but also demonstrates the potential of multi-physics simulation in offering theoretical support and prediction for BES configuration design as well as optimization.

Top-ii-vol: Massively Parallel Scalable Meshing for Seismic Risk Assessment of Nuclear Sites

High performance computing is widely used for conducting high-resolution geophysics Finite Element Method (FEM) simulations. These simulations are crucial for risk assessment at nuclear sites and help gain deeper insights into underlying physics. However, generating FEM-compatible meshes from point-cloud data – which often serves as input for mesh generation from geomodelling tools – poses significant challenges due to the lack of associated CAD data and extremely large-scale nature. This article introduces a workflow for automatically converting Digital Elevation Model (DEM) point-cloud data into three-dimensional unstructured volumetric meshes. Leveraging domaindecomposition method via the parallel MPI I/O programming, our meshing algorithm efficiently constructs meshes, accommodating an arbitrary number of CPUs and enabling either single or distributed mesh generation. Demonstrating parallel efficiency and scalability, we produced a 68 billion element tetrahedral mesh from real DEM point-cloud data of the Cadarache region in France in approximately 1 second using over 24000 processing units. Meshes produced by this technique are utilized for seismic hazard FEM simulations, one of which is presented in this study. Scalability tests on massively parallel computers show high scalability, with quasi-linear strong scaling characteristics up to 24000 processing units.

Nano-enzyme functionalized hydrogels promote diabetic wound healing through immune microenvironment modulation.

Non-healing diabetic wounds often culminate in amputation and mortality. The main pathophysiological features in diabetic wounds involve the accumulation of M1-type macrophages and excessive oxidative stress. In this study, we engineered a nano-enzyme functionalized hydrogel by incorporating a magnesium ion-doped molybdenum-based polymetallic oxide (Mg-POM), a novel bioactive nano-enzyme, into a GelMA hydrogel, to obtain the GelMA@Mg-POM system to enhance diabetic wound healing. GelMA@Mg-POM was crosslinked using UV light, yielding a hydrogel with a uniformly porous three-dimensional mesh structure. In vitro experiments showed that GelMA@Mg-POM extraction significantly enhanced human umbilical vein endothelial cell (HUVEC) migration, scavenged ROS, improved the inflammatory microenvironment, induced macrophage reprogramming towards M2, and promoted HUVEC regeneration of CD31 and fibroblast regeneration of type I collagen. In in vivo experiments, diabetic rat wounds treated with GelMA@Mg-POM displayed enhanced granulation tissue genesis and collagen production, as evidenced by HE and Masson staining. Immunohistochemistry demonstrated the ability of GelMA@Mg-POM to mitigate macrophage-associated inflammatory responses and promote angiogenesis. Overall, these findings suggest that GelMA@Mg-POM holds significant promise as a biomaterial for treating diabetic wounds.

A Dawson-type {P4W24} modified using phenylphosphonic acid with excellent proton conductivity.

A case of organic-inorganic hybridized phosphotungstate modified using aromatic organophosphonic acid, K4Na4H11[KCo2(H2O)10P4W24O92{(PhPO)2}]·48H2O (1), was successfully synthesized in conventional aqueous solution. The prominent structural feature is that the total structure of [KP4W24O92{(PhPO)2}]23- resembles a V-shaped structure, which was stabilized by two [Co(H2O)5]2+ ions. Furthermore, it can be connected into a three-dimensional mesh structure using K+ ions. Surprisingly, 1 possesses a remarkably high proton conductivity of 1.59 × 10-2 S cm-1 at 95% RH and 318 K probably due to the fact that its structure contains large amounts of lattice water molecules, coordination water molecules and counter cations.

Understanding erosion resistance mechanisms of sodium aluminate silicate hydrate in erosion environments: a molecular dynamics study.

Sodium-aluminate-silicate-hydrate (NASH) gel, as the primary reaction product stimulated by alkali in silica-aluminum-rich minerals, influences the mechanical and durability properties of geopolymers. In erosion environments, NASH demonstrates superior compressive strength and erosion resistance compared to hydration products of ordinary Portland cement. However, the underlying erosion resistance mechanism of NASH under such conditions remains unclear. Therefore, this study employs molecular dynamics research methodology to investigate the alteration in performance and deterioration mechanism of NASH in erosive environments. The findings reveal that in Na2SO4 solution, the infiltration of H2O molecules and Na+ ions into the three-dimensional mesh structure of NASH results in slight expansion and reduced tensile strength. Although H2O intrusion induces hydrolysis of the three-dimensional skeleton, the adsorption sites within NASH possess the capability to capture externally introduced Na+ ions. During tensile loading, Na+ ions can interact with reactive oxygen species produced through stretching or H2O molecule-induced decomposition of the internal framework, facilitating the repair of fractured structures. Consequently, this process partially alleviates tensile rupture, modifies the fracture damage mode, enhances overall toughness, and improves resistance against sulfate attack.

Comparison of three-dimensional mesh (3D mesh) without fixation versus polypropylene mesh with fixation in patients of inguinal hernia undergoing totally extraperitoneal repair

Comparison of three-dimensional mesh (3D mesh) without fixation versus polypropylene mesh with fixation in patients of inguinal hernia undergoing totally extraperitoneal repair

Growth of freestanding GaN crystals on three-dimensional mesh porous substrates by HVPE

The effect of two-step etching on a substrate surface structure was investigated, and the nucleation mechanism and dislocation evolution of HVPE-grown GaN on porous structures were studied in depth.

Design and Analysis of a Bionic Skate Based on MPF Movement Patterns

This paper uses pectoral fins fluctuation pattern class triangular skate as the object of study. The skate generates waveforms through its broad pectoral fins, which are transmitted backwards to push the water backwards, and the reaction force of the water obtained is the forward thrust i.e. the MPF pattern. The fins are designed to meet the fluctuation pattern of the sinusoidal function. A prototype pectoral fin of the ray is analysed to establish the kinematic model of the fluttering wing, the envelope coefficients are designed to decouple and simplify the kinematic equations, and a three-dimensional mesh is drawn using MATLAB; fluid simulation is carried out by Fluent to obtain the vortex cloud; the bionic ray is tested and tested to meet the actual requirements.

Composite starch films as green adsorbents for removing benzo[a]pyrene from smoked sausages

Benzo[a]pyrene (BaP), which is emitted during the processing of smoked sausages, accumulates in sausages and poses a serious threat to human health. This study focused on the removal of BaP from sausages and accompanying particulate matter (PM) during the smoking of sausages by films formed by combining corn starch (CS) with K-carrageenan (KC)/sodium alginate (SA). Initially, the effects of different additions of KC and SA on the rheological analysis, thermogravimetric analysis (TGA) and film-forming properties of the composite films were investigated. The BaP reduction capacities of CS-KC and CS-SA composite films in sausage were 41.1%-47.0% and 54.2%-56.5%, respectively, because the three-dimensional mesh structure of the composite films provided a large number of adsorption sites. Finally, kinetic studies demonstrated that BaP control in composite films is mainly achieved by intraparticle diffusion. Therefore, due to its excellent recyclability and biodegradability, composite starch film has a promising application in smoked meat products.

Preparation and characterization of EI-Co/Zr@AC and the mechanisms underlying its removal for atrazine in aqueous solution.

Atrazine, a widely used herbicide in agriculture, is detrimental to both the ecological environment and human health owing to its extensive use, poor degradability, and biotoxicity. The technology commonly used to remove atrazine from water is activated carbon adsorption, but it has the problems of difficult recovery, secondary contamination, and a low removal rate. To efficiently remove atrazine from agricultural wastewater, in this study, a new environmental material, embedding immobilization (EI)-Co- and Zr-modified activated carbon powder (Co/Zr@AC), was prepared by immobilizing the bimetallic Co/Zr@AC via EI technique and employed to remove atrazine. When preparing EI-Co/Zr@AC, the single-factor experiment was conducted and determined the optimal preparation conditions: sodium alginate 2.5% (wt), calcium chloride 4.0% (wt), Co/Zr@AC 1.0% (wt), and bentonite 2.0% (wt). The prepared EI-Co/Zr@AC has a three-dimensional mesh structure and many pores and also possesses good mass transfer performance and mechanical properties. The removal efficiency by EI-Co/Zr@AC for the removal of 5.0 mg/L atrazine from 50 mL was 94.1% at pH 7.0 and 25°C, with an EI-Co/Zr@AC dosage of 0.8 g. The mechanistic study showed that the pseudo-second-order kinetic model could describe the removal process better than the pseudo-first-order kinetic model, and the Freundlich isotherm model fit better than other isotherm models. Additionally, the synthesized EI-Co/Zr@AC spheres demonstrated good reusability, with the atrazine removal rate remaining 70.4% after five cycles, and the mechanical properties of the spheres were stable.

Enhancing strategies for the activity and H2O resistance of MnCo-CMS flexible SCR catalysts and hydrophobic modification by modulating the surface energy

Melamine sponge is a flexible organic rubber-plastic foam characterized by its highly porous three-dimensional mesh structure. By optimizing the carbonization process of the melamine sponge, NH3-SCR catalysts with enhanced flexibility were developed. In this study, MnCo-CMS (Carbonized melamine sponge) catalysts were synthesized using the impregnation method. Response surface methodology (RSM) and central composite design (CCD) were employed to investigate the effects of impregnation time, loading, and calcination temperature on the mass reaction rate and N2 selectivity. The results showed that loading had the most significant influence, followed by calcination temperature and impregnation time. Under the optimal preparation conditions of 32.5 wt% loading, the calcination temperature at 420 °C, and the impregnation time for 342 min, the mass reaction rate could reach 11.02 cm3min-1g−1, and the N2 selectivity could achieve 87.4 %. Experimental validation confirmed that various preparation processes resulted in catalysts with high SCR activity (rate constant k > 9.5 cm3min-1g−1 and N2 selectivity > 80 %). The Mn-Co loading should be within the range of 28–36 wt%, the calcination temperature within the range of 380–420 °C, and the impregnation time should be 150 min or more. Materials with low surface energy could result in excellent hydrophobicity. In this study, it was found that melamine sponges could be modified into low surface energy carbon foams by temperature modulation. The change in surface energy was utilized as a modification approach to enhance the water resistance of the NH3-SCR catalyst. Importantly, the optimized process significantly improved the stability and water resistance of the catalysts.