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Liver sinusoidal endothelial cells (LSECs) are the predominant endothelial cells (ECs) and the most abundant type of non-parenchymal cells (NPCs) in the liver, lining the low-shear sinusoidal channels. LSECs are not only a physical barrier but play multifunctional roles, like endocytosis, antigen presentation, and immune cell trafficking, as well as positively promoting disease development patho-physiologically. In physical conditions, LSEC demonstrates unique structures that can distinguish it from other endothelia in other organs. Capillarization of LSEC, a dysfunctional phenotype, is the essential event from fibrosis to cirrhosis and finally to hepatocellular carcinoma (HCC). They further precede angiogenesis and vasoconstriction, facilitating the immunosuppressive microenvironment. Targeting abnormal ECs in HCC has demonstrated great potential in enhancing the efficacy of immunotherapy. Multiple approaches have been employed for EC normalization, including nanoparticles (NPs). Evidence has shown that NP-mediated drug systems can greatly normalize ECs and increase anti-tumor efficiency. This review discusses multiple NP platforms, focusing on their potential in HCC. We further discuss the immune modulation of tumor microenvironment (TME) through NP application in HCC.

Fused Filament Fabrication (FFF) is one of the most emerging techniques nowadays. Affordable, easy to use, economical, for a broad audience − from specialists to home users. These are only several of its advantages. A disadvantage is the limited number of available filament types, especially those with high performance. Therefore, the aim of the work was to investigate the properties of custom–made filament printouts based on polylactic (PLA), graphite (G) and molybdenum disulfide (MoS2).This work looked at structural and thermal analysis, acoustic performance, EMI shielding, and electrical and thermal properties, including thermal conductivity and heat diffusivity. The following were considered during the study: type of printing architecture, infill density, and filament formulations. Among the best values, which were obtained for the highest loaded sample based on 15 wt% graphite and 2 wt% MoS2 (G15/M2), where EMI shielding effectiveness surpassed SETOT ∼ 17 dB (per 1 mm sample thickness), electrical conductivity remained at a low level. It exceeded σ ∼ 0.2 S/m; thermal conductivity was slightly over κ ∼ 0.4 W/mK, and heat diffusivity was almost α ∼ 0.4 mm2/s.This work is the first step in designing high-performance materials dedicated to advanced applications based on the FFF technique.

Concrete has been a material of choice when it comes to building materials for decades. However, concrete has a number of challenges in which a major challenge being microcracking leading to excess damage and wastes. The development and advancement of self-healing technology throughout the past decade have seen the popular use of immobilization as a way of protecting bacteria from the harsh environments found in cementitious materials. This paper reviews the materials used for immobilization, categorising into organic materials and inorganic materials, and investigates the various immobilization techniques used to immobilize bacteria into polymeric structures and porous materials. The study evaluates the key findings in literature surrounding immobilization materials and methods as well as highlighting possible alternative sustainable materials and methods including waste/by-product resources. It was found that inorganic materials were superior to organic material in terms of self-healing and mechanical properties, with nanomaterials producing the highest crack closure of 1.20 mm. Various immobilization techniques efficiency was tested comparing microencapsulation, vacuum impregnation and adsorption methods. Further studies are needed to understand the relationship between carrier materials and cementitious matrix and explore the possible use of nanomaterials as a way of uniformly distributing bacteria in cementitious matrix.

There have been many studies on the ground state of phononic crystals, but few studies on the nature of the excited state. In this paper, we introduce the asymmetric Klein tunneling method in phononic systems, which enables selective direction and control of elastic waves by inducing polarization through an external field in an artificial barrier. Using tight-binding theory, we systematically studied phononics in a super-honeycomb structure, demonstrating the anisotropic transition properties of excited state phonons through a matrix model involving the ground state’s s-type and the first excited state’s p-type wave functions. Additionally, we exploit the thermal sensitivity of epoxy to achieve localized thermal field-induced distortion of the bottom flat band, forming a tiled Dirac cone, and thereby creating a reconfigurable polarized artificial barrier in the elastic wave system. Elastic waves propagate in these systems with topological charge conservation. Combining this with the theoretical of excited-state phonons, we demonstrate asymmetric Klein tunneling with directional selectivity in the elastic wave carriers, and systematically investigate the performance of this tunneling. Furthermore, we design a four-port elastic waveguide based on the principle of asymmetric tunneling, which achieves exceptional directional selectivity of elastic wave signals by adjusting the polarization direction of barriers at the junctions. These studies not only extend the application of Klein tunneling in elastic wave systems but also open new research avenues for the study of elastic wave devices controlled by various external fields, showing direct application potential in elastic wave signal processing.

The autogenous self-sealing model has been researched in previous work, which could help to characterize the self-sealing process with crystalline products. The model outcome was presented in the form of leakage water flow, which demonstrates the self-sealing capacity or the recovery of watertightness. While in the research area of cement-based material self-sealing, the expansive agent cannot be neglectable, for example the superabsorbent polymer (SAP). Especially for the building components exposed to free water, an efficient water flow blockage after cracking is crucial to ensure stable service. Hence in this study, the self-sealing process of a granular expansive agent inside the crack of cement-based material was simulated. The model outputs were compared with experimental results to verify the reliability. Additionally, the autogenous self-sealing model was incorporated into this model to simulate the “crystallization-expansion” synergetic self-sealing. The contribution of crystalline product and expanded EA to water flow blockage were compared during the crystallizing process. Overall, this model is of great use to evaluate the role of expansive agent on water flow blockage after the cement-based material cracking in hydraulic engineering or engineering components exposed to water.

Solid Rocket Motors (SRMs) rely on solid propellants, directly impacting the energy capacity of launch vehicles. High energy density material (HEDM) propellant exhibits superior energy density owing to the incorporation of a substantial quantity of energetic particles. However, the elevated particle fill ratio makes the formation of pores more prevalent during the manufacturing process of propellants. These pores, representing default defects, are indispensable factors in the investigation of mechanical properties of propellants. This study investigated default defects effects on HEDM propellants, analyzing both microscopic and macroscopic perspectives. Utilizing micro-CT imaging, the microstructure and default defects were characterized. Subsequently, using the cohesive zone model (CZM), microscopic damage evolution was depicted with the representative volume element (RVE) model, allowing in-depth analysis. Furthermore, a damage constitutive model, based on microscopic damage, was developed, with its softening function calibrated using microscopic damage evolution characteristics. Implemented into ABAQUS via user-defined material subroutine (UMAT), this model enabled the prediction of the mechanical response of HEDM propellants with different defects. The results demonstrate that the developed model accurately predicts the mechanical responses of HEDM propellants with different defects, showcasing the potential of macro-microscopic approaches in analyzing propellants with default defects.

Owing to of its freedom from energy inputs, radiative cooling is emerging as a frontier in renewable energy research. Recent advances in nanophotonic structures have enabled scalable passive daytime radiative cooling (PDRC), such as porous polymer films, which can spontaneously reflect solar irradiance and emit heat to the ultra-cold outer space. However, there is still limited fundamental understanding of these nanophotonic structures underlying the cooling effects of these porous polymer-based PDRC films. Hence, we performed optical simulations validated by experiments to quantify how the spatial distribution of nanopores in the polymer film affect its PDRC performance. Our simulation results showed that the influence of spatial distribution of pores on the PDRC performance replies significantly on solar reflectance. A gradient distribution of pores with random pattern can remarkably enhance solar reflectance under direct sunlight up to 153.4 %, while maintaining a slight variation of thermal emittance

Providing a comprehensive assessment of the creep-fatigue life of critical structures in nuclear power facilities is important for structural integrity and performance requirements during service. The data-driven modeling method can set aside traditional mechanical theory and use experimental data to drive creep-fatigue performance modeling directly, avoiding complex parameter fitting. A sufficiently robust purely data-driven model must be supported by a large amount of training data, which means significant time and financial costs. To address these issues, a physics-informed neural network (PINN) is proposed in this work to predict the creep-fatigue life of Inconel 617 at high temperatures, where the physical constraints are introduced to enhance the physical fundamentals. The prediction results show that introduced physical constraints promote the stability of prediction performance and analysis based on the strength of physical constraints provides valuable guidance for creep-fatigue modeling to select the suitable architecture for building PINN. The SHapley Additive exPlanations (SHAP) method and dependency analysis are utilized to reveal the intrinsic mechanism of the properties and structure of PINN.

Step adhesive joints have a special characteristic quite different from other joints. When initial delamination occurs in other joints such as butt, lap and scarf joints, final failure always occurs. In these cases, the external stress causing initial delamination σcInitial is equal to the final failure stress as σcFinal = σcInitial. However, in step joints, the final failure stress σcFinal can be greater than the initial delamination stress σcInitial

Warpage in semiconductor packages is a critical issue that affects their reliability and performance. This study aims to minimize the warpage of a bi-material dummy package by optimizing the post-mold curing (PMC) temperature profile. A warpage simulation model was developed considering the viscoelastic properties and cure shrinkage behavior of the epoxy molding compound (EMC). A compression molding monitoring system was also developed to analyze the cure behavior of the EMC. The gelation point of the EMC during compression molding was determined using a dielectric sensor, while cure shrinkage behaviors were analyzed using a fiber Bragg grating sensor. Viscoelastic properties were characterized through stress relaxation tests, and thermal properties were measured using three-dimensional digital image correlation. The developed simulation model was used to optimize the PMC temperature profile using a genetic algorithm. Experimental validation showed that the optimized temperature profile reduced the warpage from ∼1519 μm to 486 μm compared to a linear profile. The findings of this study have broader implications for the design and manufacturing of semiconductor packages, as the proposed approach can be applied to minimize warpage and improve package reliability.

Lattice-infilled structures possess prominent properties at relatively low mass, which are of great significance in academic investigations and engineering fields such as aerospace science and biomedical applications. However, both the macro geometry and relative density distribution of the infilled microstructure exert considerable influence on performances of lattice-infilled structure and the structural manufacturability needs to be considered. In this work, an optimization design methodology for self-supporting additive-manufactured lattice-infilled structures is proposed, in which the macro geometry and relative density distribution of the microstructure are concurrently optimized. Microstructure is infilled after topology optimization and octree structure is introduced into the boundary layers of the lattice core to support the top shell during fabrication. The effectiveness of the proposed optimization design method for self-supporting additive-manufactured lattice-infilled structures was proved by both three-point-bending test and full-scale finite element simulation. Compared with the uniformly-infilled sample, mass-specific stiffness and strength of the topologyoptimized sample were improved by 41.2% and 112.1%, respectively. The proposed design method for lattice-infilled structures provides potential for designing additive-manufactured high-performance lightweight structures, which will broaden the boundaries of lattice structure in engineering applications.

Nacre of Pinctada maxima is a natural biomineralized matrix, appeared 7 million years before hominins. In this study, we converted nacre into a self-setting particle bound with multiple calcium orthophosphates that reassemble mammals’ bone mineral matrices for induction of bone regeneration. The nacre-based calcium orthophosphates composite (NCOC) exhibited a compression strength of 10 MPa, which is superior to human trabecular bone. In vitro bioactivity tests revealed the formation of apatite with nano-porous flake-like crystals on the composite surface that mimic HA structure of a human bone matrix. NCOC demonstrated efficient attachment and proliferation of osteoblast cells, promoting osteogenic differentiation by increasing expressions of RUNX2 and OPN. In vivo studies using rabbit back fascia demonstrated that NCOC displays better bone healing and biocompatibility than conventional bone substitute apatite in critical bone defect models. The degradation of calcium carbonate crystal in vivo does not compromise structural integrity of NCOC. Overall, our data showed that NCOC produced through self-setting reactions, presents advantages such as accelerated biodegradation and osteostimulative properties, making it a promising bone substitute for effective bone regeneration.

In this work, a novel dual-phase metamaterial, named as “hybrid lattice metamaterial (HLM),” are designed and fabricated by combining reentrant and sea-urchin (SU) based surface-lattice (SL) structure with polyamide12 (PA12) material via material extrusion (MEX) process. Four different designs with varying reentrant truss thicknesses of 0.8 mm (H1), 1.0 mm (H2), 1.2 mm (H3), and 1.5 mm (H4) have been modified to assemble seamlessly with the empty spaces within the SL structure. Quasistatic compression tests were conducted to evaluate the deformation modes and compression characteristics. The findings from quasistatic experiments were subsequently validated using numerical simulations. The H4 metamaterial exhibited superior structural properties, with 42 % increase in stiffness and 35 % enhancement in specific energy absorption compared to only SL structure. Additionally, dynamic sinusoidal compression tests were conducted to evaluate the dynamic elastic ratio (DER), hysteresis work and viscoelastic properties using the tan δ. The H4 metamaterial outperformed the SL in all dynamic properties, with a 50 % increase in elastic modulus and 36 % increase in hysteresis work. This study shows metamaterial properties can be tailored for specific requirements. SL structure facilitate elastic recovery, while H4 metamaterials offer superior energy absorption and stability, making it well-suited for protective equipment and impact-resistant components.

Frequency selective surfaces (FSSs) are significant for the efficient and accurate transmission of microwave signals due to its ability to selectively shield electromagnetic (EM) waves of different frequencies. In some special scenarios, mechanical properties are vitally required. Herein, a flexible frequency selective fabric (FSF) is proposed. Different from traditional FSSs or reported FSFs, aramid/carbon fiber woven fabric serve as the flexible substrate in which carbon fiber provides functionality instead of metallic materials, and patches made of carbon fiber prepreg are periodically applied for property reinforcement. Equivalent circuit model is used to guide the basic determination of patch’s geometry, and it is further optimized via full-wave simulation software HFSS. A simulation model that reasonably reflect the correlation between structure and frequency-selection characteristic is provided, and structural factors affecting the characteristic are analyzed and discussed. Further, an FSF sample is prepared and its frequency response is measured. Measurement revealed the FSF selectively shields EM waves in the frequency range of 8.9 GHz to 11.4 GHz, and is of the bandpass-bandstop-bandpass characteristic. Benefit from EM property and flexibility, the proposed FSF has advantages in applications pursue lightweight, high strength, and require excellent EM functionality, such as aerospace and structure-EM function integrated products.

The effect of the combined addition of Zn and Ni on the mechanical properties and microstructures of an intermetallic compound (IMC) layer of dissimilar welds of Al alloy 5052 to low-carbon steel was systematically investigated. A maximum weld strength of 120 MPa was achieved with the combined addition of Zn and Ni, which was 193 % higher than that of the weld produced without the addition of Zn or Ni. The addition of Zn resulted in the formation of soft Fe–Zn IMCs in the IMC layer, which reduced the hardness of the IMC layer. Additionally, the combined addition of Zn and Ni promoted the formation of Fe–Zn IMCs, which further softened the IMC layer. Further softening of the IMC layer, reduction in the thickness of the IMC layer, and suppression of the formation of defects in the IMC layer, achieved by the combined addition of Zn and Ni, drastically improved the weld strength.

Bone microstructures or scaffolds mimicking natural bone characteristics find widespread applications in bone tissue engineering (BTE). To accurately replicate a personalized bone structure, we developed a heterogeneous scaffold by combining medical image data with the octree adaptive subdivision technique. The transformations between Hounsfield units (HU)-strength and strength-lattice features were implemented for mapping bone information to the scaffold. Initially, HU values from computed tomography (CT) images were smoothly converted into corresponding strengths through a rational Bezier curve. Then, these strengths were further translated into the features of lattice structures, specifically the strut diameter and subdivision level. The novel concept of adaptive octree subdivision, executed on the lattices, allows for controlling bone porosity and mechanical property even at local levels. As a result, a personalized heterogeneous scaffold accurately simulating natural bone structure was designed and manufactured for bone grafting application on a 3D-printed alveolar model. The scaffold has an outer cortical bone layer capable of withstanding pressures of up to 208.2 MPa, while the inner cancellous bone exhibits a high porosity ranging from 77.6 % to 93.6 %. The research provides an elegant yet effective approach to the generation of bone microstructures, opening up practical BTE applications.

Microwave absorbing materials (MAMs) are used to prevent electromagnetic pollution and enhance equipment stealth. However, their limited absorption intensity and narrow effective bandwidth restrict their applicability. MAMs with a single absorption mechanism, whether dielectric or magnetic, often exhibit poor impedance matching. This paper introduces a new multiscale approach—encompassing microstructures, mesostructures and macrostructures—for designing high-performance MAMs. At the microscopic–mesoscopic level, Pomb materials derived from pomegranate peel are combined with magnetic nanoparticles (Co3O4) using a hydrothermal method. The microwave absorption properties of these composite materials were examined by varying the proportion of Pomb materials in the absorber. The effective absorption bandwidth (EAB) reached 5.5 GHz for a thickness of 2.3 mm. At the macroscopic level, a metastructure based on Pomb@Co3O4 (0.1 g) was designed to achieve ultrabroadband absorption with an EAB of 15.56 GHz, a range of 2.24–18 GHz and a total thickness of 15 mm. Additionally, the radar cross-section value of Pomb@Co3O4 (0.1 g) is below − 10 dB m2 across the angle range of − 60° to 60°, with a maximum scattering intensity of only − 7.6 dB m2. This multiscale structure design offers a promising direction for future research and development in MAMs.

The present study proposes an advanced multi-field modeling approach to optimize in silico subcutaneous insulin release. We introduce a generalized fluid-pharmacokinetics framework, integrating syringe injection and subcutaneous permeability, thus advancing a first-of-its-kind computational model of insulin delivery port. The proposed theoretical framework comprises three main elements: (1) a realistic geometry model of a commercial port device and the surrounding subcutaneous tissues; (2) a staggered fluid dynamics model of syringe injection coupled with a multi-compartmental model of insulin absorption within a porous medium; (3) a computational-based device optimization to minimize the onset of lipodystrophies due to multiple injection procedures. A novel tissue lesion model is advanced, linking local subcutaneous pressure levels to altered permeability that comprise accumulation effects due to repeated injections. The computational framework was fine-tuned according to state-of-the-art experimental evidence, and extensive numerical analyses predicted unexplored insulin port devices behaviors thus allowing comparison of computed haematic insulin profiles with those obtained clinically. Accordingly, a vast parametric analysis was performed to identify the optimal conditions that minimize tissue lesions and support prolonged device usage.

The two deformation modes of meta-biomaterials during cyclic loading have been revealed: stochastic and deterministic strut failure processes. Biomimetic Voronoi structures with a range of strut thicknesses and number of cells per unit volume are printed. We show that when the strut thickness is 200 μm or above, the fatigue fracture process of the lattice is deterministic and the fatigue scatters are below 15%. As the strut is thinned to 150 μm, the local failures occur randomly within the structure, which may lead to a high fatigue scatter (>30%). The two distinct behaviours result from the processing limit of the laser powder bed fusion technique. We demonstrate that the fatigue scatter and the location of the failure process within the lattice are related to the probability that a cluster of unconnected struts larger than a critical value can exist within the lattice. Unlike solid parts, porosity hardly triggers any damage in metallic lattices during cyclic deformation. The discovery of the Janus-like failure process opens up our understanding of meta-biomaterials and defines the pathway towards the design of mechanically durable intricate implants.

In the dynamic interaction between the runner and the ground, the running shoe is the only medium that bears the impact force of body weight and plays a crucial role in athletic performance. Traditional designs do not adequately consider the different shapes of the foot, which often leads to discomfort and aggravation of foot disorders. This study presents an innovative approach to running shoe midsole design using 3D-printed chiral negative poisson’s ratio (NPR) structures to enhance shock absorption and support, thereby optimizing biomechanical performance and comfort. Using computer-aided design (CAD) and computer-aided engineering (CAE), the biomechanical effects of different midsole structures has been explored through finite element analysis (FEA). The study focuses on optimizing the cushioning, propulsion and stability of the midsole to mitigate the impact on the ankle and knee. Static compression and dynamic impact simulations were utilized to comprehensively select optimized design of midsole structure and the selected structures was 3D printed to validate the biomechanical benefits in a wear trial. The results of the study highlight the superior performance of chiral NPR structures in reducing forefoot stress during standing and movement and advance the design and functionality of 3D printed materials in running shoes.

Novel concepts for efficient compact spectroscopy are extensively researched due to their fundamental applications in prominent fields such as chemistry, biology, and physics. Here, with an unprecedented spectral-azimuthal resolution, such a concept is introduced and exemplified in the mid-infrared, in which its advantages are paramount and have yet to be established industrially. The concept is based on the design and instrumentation of optical absorption spectral tuning (or sensitivity) to the relative azimuthal component of light impinging on specifically designed metamaterials (MMs). The inversely-designed MMs offer perfect photo-absorption inside λ0/200 ultra-thin layer of lead telluride. Two small-footprint system designs are proposed to instrument the spectral-azimuth-angle tuning for spectrometry. The first is based on a single or few spinning MM layout elements, and the second, to avoid spinning, utilizes a fixed focal-plane-array approach. The latter exploits the inherent variations in the local azimuthal-incidence angle. While low absorption is the Achilles heel of conventional mid-infrared photodetector spectrometers, the optimized MMs, besides their unique spectral-azimuth-angle tuning functionality, provide giant absorption enhancement, facilitating higher resolution and even smaller in-plane form factor. The highlighted concept opens an additional dimension to encode-decode spectral information, yielding profound advantages over conventional designs, such as those based on diffraction gratings.

The restoration of critical-size load-bearing bone defects calls for the application of bioactive scaffolds that are regenerative, osteoconductive, and demonstrate mechanical strength comparable with natural bone. Novel hydroxyapatite (HAp) scaffolds sourced and fabricated through the biomorphic transformation of rattan wood (GreenBone-GB) were laser-drilled (LD) with parallel and lateral sub-millimetre channels, which enhanced the overall porosity for promoting the flow of cells and fluids throughout the scaffolds. The compositional analysis of the LD scaffolds confirmed the presence of the Ca5(PO4)3OH and Ca3(PO4)2 phases, with no evidence of drilling contamination. Water jet laser drilling enhanced the interconnecting porosity of the morphogenic scaffolds by 22.5 %, without obstructing the intrinsic uniaxial fibrous structure inherited from rattan wood. Across eight varied drilled patterns, the resulting scaffolds preserved the structural integrity and exhibited compressive strength ranging from 6.74 ± 1.25 to 10.18 ± 0.43 MPa, while the Vickers Hardness was comparable with natural bone. Cell viability assessments confirmed that the LD scaffolds exhibited no toxicity and presented >90 % cell viability. We demonstrate that laser drilling effectively enhanced the pore volume for improved osteoconductivity via cell migration in the bio-morphogenic GB-structure. Since the GB scaffolds are CE-marked products, laser drilling for pore surface engineering could provide improved scaffolds for clinical use.

Elemental powder sintering is an important low-cost preparation method for NiTiNb shape memory alloys. Usually, the performance is poor due to high impurity content and macroscopic defects. In this study, high-strength NiTiNb alloys without macroscopic defects were successfully prepared using mixed elemental powders based on the previous investigation. Higher sintering temperature and Nb addition brought about faster atomic diffusion, which strongly affected the densification, grain size, phase composition and Nb solid solution, and further determined the transformation temperature and mechanical properties. The transformation temperature decreased with increasing Nb solid solubility. A high thermal hysteresis of 72–75 °C was obtained by nano-Nb precipitation. The compressive strength reached 1662–2185 MPa. The recovery properties gradually decreased with the increase of large Nb particles in the matrix, which should be optimized in further studies. Overall, the addition of Nb drastically reduced the sintering temperature of elemental NiTi powders, which was conducive to suppressing the loss of liquid phase and promoting homogenization. It provides a new idea for the preparation of high-performance, fully dense and low-cost NiTi-based alloys.

A novel approach of Metal Additive Manufacturing using Powder Sheet (MAPS) is developed and demonstrated. A flexible metal particle-polymeric binder composite sheet is employed as innovative feedstock in this new method and this approach offers enhanced health and safety. MAPS successfully printed dense samples (99.99%). The chemical composition of the printed alloy resulted enriched in carbon compared to the feedstock powder due to the C pick-up during MAPS, leading to distinct microstructures and enhanced mechanical properties compared to those of laser beam powder bed fusion (PBF-LB/M) benchmark samples. In particular, the microstructural examinations of the MAPS samples show a coarser carbide network stable even after thermal treatment at high temperatures, while the tensile tests revealed that MAPS samples have a higher mechanical strength than the PBF-LB/M counterparts but possess lower ductility. The modification in the chemical composition indicates a strong potential for in-process alloying through MAPS. The demonstrated MAPS approach offers a novel avenue for manufacturing functional metal components with bespoke compositions and resulting properties.

The effective containment of fission products (FPs) within tri-structural isotropic (TRISO) fuel particles is crucial for the safety and efficiency of High Temperature Gas-cooled Reactors (HTGRs). Combining multi-scale (µm to nm) and multi-dimensional (2D and 3D) analysis, this study focuses on the migration mechanisms of silver (Ag), for which the Ag-110 m FP isotope is radiotoxic, facilitated by reactions with palladium (Pd) alloys and the silicon carbide (SiC) layer at elevated temperatures (1300–1500 °C). Three primary pathways for Ag migration are identified: (1) diffusion in solid palladium silicide to form (Pd,Ag)2Si, (2) infiltration through cracks and pores in the carbon phase, and (3) liquid phase migration along SiC grain boundaries. Especially at temperatures above the melting point of Pd2Si (1404 °C), a ‘dissolution-recrystallisation’ mechanism is proposed of the Ag-Pd-Si liquid phase migrating along SiC grain boundaries. The study employs state-of-the-art in-situ heating transmission electron microscopy (TEM) techniques to directly observe the dynamic migration processes of Pd silicide within SiC, providing unprecedented insights into the liquid behaviour in TRISO fuel. These findings highlight the significant role of liquid phases in determining the transport of FPs through the TRISO-SiC which is vital for developing strategies that enhance the safety and efficacy of HTGRs.

The maturity and patency of arteriovenous fistula (AVF) are essential for patients undergoing hemodialysis. Dysfunction of AVF due to neointimal hyperplasia (NIH) presents a significant clinical challenge. While balloon dilation therapy and open surgery can address this issue, they are associated with a higher likelihood of restenosis and reduced long-term durability. Therefore, there is an urgent need to establish a new method for inhibiting NIH to prolong the patency of AVF treatment. In this study, we developed a local vascular-encapsulated sustained-release drug delivery system containing degradable rapamycin nanofiber membrane patches (R-NFMs). During surgery, R-NFMs were wrapped around the anastomotic site of the AVF and the venous outflow tract. In vitro assessments demonstrated the consistent and stable release of rapamycin from the R-NFMs, confirming the material’s non-toxicity and its support of healthy cellular morphology. Animal studies further revealed that the experimental group showed significant reductions in neointimal and medial hyperplasia, as well as decreased expression of α-SMA, compared to controls. In conclusion, these findings suggest that R-NFMs are effective in inhibiting NIH and may serve as an innovative preventative approach to this pervasive issue.

Cytokin storms play a key role in the pathogenesis of acute lung injury (ALI) caused by sepsis, in which pulmonary macrophage PANoptosis is involved. At present, the main treatment methods for sepsis-induced ALI are antibiotics and fluid resuscitation, but the efficacy of these methods is unsatisfactory enough; therefore, the development of new therapeutic methods is urgently needed. In this study, we developed a novel bionic nanoparticle (R@ZQC NPs) using ZIF-8 nanoparticles as a carrier, internally supported with ginsenoside Rb1, and externally coated with quaternated chitosan and a macrophage membrane layer by layer. The biomimetic nanoparticles controlled the release of Rb1, had good biocompatibility, strong antibacterial activity, and targeted the inhibition of pulmonary macrophage PANoptosis. In vitro and in vivo, R@ZQC NPs effectively inhibited the activity of Escherichia coli and reduced mitochondrial damage by activating the AMPK pathway, thus alleviating the inflammatory response and ameliorating sepsis-induced ALI. In summary, this study revealed the great potential of R@ZQC NPs for antimicrobial activity, targeted inhibition of macrophage PANoptosis and reduction of the inflammatory response and represents the first attempt of R@ZQC NPs in the treatment of sepsis-induced ALI. This study provides new therapeutic ideas and strategies for the clinical treatment of sepsis-induced ALI.

The influence of Er content on mechanical properties and microstructural evolution of highly-alloyed Mg-10Gd-5Y-xEr alloys (x = 0, 2, 3.5, 5, and 6.5 wt%) are investigated. The tensile strength is found to increase monotonously with increasing Er content, while the ductility is slightly reduced due to the increased formation of block precipitates. The maximum tensile yield strength and ultimate tensile strength are achieved to be 296 MPa and 374 MPa, respectively, within the studied concertation interval. Solid solution strengthening and grain refinement are demonstrated to dominate the increase of tensile yield strength upon Er content, where the latter becomes the primary strengthening mechanism at relatively high Er contents (> 5 wt%). It is closely related to the consumption of Gd and Y in solid solution by the precipitation of Mg24RE5 particles and alloying element segregation at grain boundary. The significant reduced grain size of dynamic recrystallized grains upon Er content is attributed to the promoted dynamic recrystallization via particle stimulation nucleation and the retardant grain growth emerging from the drag and pinning effect of alloying element segregation and nano-precipitates at grain boundary.

Co-doped NiMnSn Heusler-type metamagnetic shape memory alloys (MMSMAs) are promising materials for the next-generation solid-state refrigeration systems due to their excellent magnetocaloric performance around the martensitic transformation, which is easily tuneable by slight changes in the alloy composition. An improvement in the thermal efficiency of active magnetic regenerator devices, a key element in magnetocaloric cooling systems, arises by obtaining powdered magnetocaloric alloys that meet technical requirements for their implementation as a feedstock material in the additive manufacturing of 3D-printed heat exchangers. In the present work, powders of Mn-rich NiCoMnSn Heusler-type MMSMAs were obtained from their ribbon form avoiding or minimizing residual stresses, the number of defects and disorder in the crystal lattice and microstructure. Since atomic order and crystallographic structure are crucial in the transformation and magnetic properties of these alloys, a complementary structural analysis of the powders after different heat treatments was performed by powder neutron diffraction. The results show that the cubic austenitic phase of the non-heat-treated melt-spun powder exhibits a highly stressed structure, which leads to an incomplete martensitic transformation and, therefore, to the coexistence of martensitic and austenitic phases at low temperatures. The magnetic structure of the austenite phase was also determined by neutron powder diffraction, obtaining a ferromagnetic coupling between 4a and 4b Wyckoff positions in the samples analysed. It was found that a heat treatment facilitates the martensitic transformation and enables the formation of a pure martensitic phase.The observed changes in the magnetocaloric performance of the powders have been understood in terms of the differently stressed structures and their impact on the martensitic transformation. A fully completed structural transformation leads to a significant increase of the magnetisation change across the martensitic transformation and, consequently, to high values of both a magnetic field induced isothermal entropy change and refrigeration capacity.

Rheumatoid arthritis (RA) is a chronic and refractory autoimmune disease that primarily affects the synovium of diarthrodial joints. Inflammatory macrophages and fibroblast-like synoviocytes (FLS) in the synovial microenvironment produce pathogenic mediators such as cytokines and proteases that perpetuate immune-mediated inflammation and contribute to the destruction of cartilage and bone. Polydatin (PD), a natural active compound, has demonstrated potential anti-inflammatory and anti-arthritic effects. However, drug development and delivery of PD is still a great challenge owing to its low solubility, short half-life, and high dose requirement. In order to overcome these drawbacks, we developed a novel nanodrug system named HA-M@PB@Ag@PD NPs. This system is composed of hybrid membrane (M), hyaluronic acid (HA), Prussian blue nanoparticles (PB NPs), PD, and chitosan-silver (Chi-Ag). In vitro experiments demonstrated that HA-M@PB@Ag@PD NPs effectively cleared ROS, promoted the repolarization of inflammatory macrophages, and induced apoptosis of RA-FLS. Using a rat model of RA, HA-M@PB@Ag@PD NPs markedly suppressed joint inflammation, inhibited synovial hyperplasia, and protected joints against destruction of cartilage and bone. Moreover, HA-M@PB@Ag@PD NPs significantly improved the synovial microenvironment of arthritic rats by reducing the number of RA-FLS and inflammatory macrophages, and facilitating the repolarization of inflammatory macrophages.

Melt electrospinning writing (MEW) combines the fundamental principles of electrospinning, a fiber forming technology, and 3D printing. The process, however, is highly complex and the quality of the fabricated structures strongly depends on the interplay of key printing parameter settings including processing temperature, applied voltage, collection speed, and applied pressure. These parameters act in unison, comprising the principal forces on the electrified jet: pushing the viscous polymer out of the nozzle and mechanically and electrostatically dragging it for deposition towards the collector. This article will reveal the correlation between the printing process parameters and the fiber morphology for curved printing fibers below the critical translation speed (CTS), and prepare controllable curved scaffolds by adjusting the electric field strength, which have fully interconnected pores and allow cells to migrate and proliferate. Furthermore, the study verified the advantages of these scaffolds through mechanical and in vitro culture experiments. The results showed that compared with the linearly printed scaffolds, the curved printed scaffolds exhibited better mechanical properties and enhanced cell attachment and proliferation.

Bone defect repair and tumor recurrence are the main challenges in the postoperative treatment of bone tumors. The incorporation of zoledronate (ZOL) into scaffolds presents a promising approach, attributed to its osteogenic and anti-tumor properties. However, there are still some unfavorable factors that make it difficult to eradicate tumor cells at the surgical site, including drug rapid release, the insufficient anti-tumor efficacy of ZOL and the multidrug resistance of chemotherapy. Herein, a novel nano drug delivery platform mesoporous silicon-coated graphene oxide (GO/MSN) and ZOL loaded nanoparticle (GO/MSN-ZOL) were developed. Then PLLA/ GO/MSN-ZOL scaffold that integrates photothermal therapy (PTT) and chemotherapy was fabricated using poly (L-lactic acid) as raw materials by selective laser sintering (SLS) technology. The GO not only imparted scaffold with photothermal properties for localized tumor cell ablation but also significantly enhanced its anti-tumor efficacy through synergistic effects in combination with chemotherapy. The mesoporous structure and large specific surface area of MSN contribute to the sustained release of ZOL. Additionally, GO could promote osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs), which in combine with ZOL’s osteoclast inhibition, enhances the bone repair capacity. This study offers a straightforward and promising strategy for treating tumor-related bone defects.

Despite increasing applications of additively manufactured parts, they still suffer from anisotropic mechanical properties and can experience cracking due to coarse columnar grain structures induced by metal 3D printing. Microstructural control is promising avenue to overcome these challenges, but requires deeper understanding of factors controlling solidification, particularly regarding grain refinement. Addressing this gap, this study explores grain refinement in Al-Cu alloys with a process-microstructure linking cellular automata-finite difference (CAFD) approach supported by single-track laser surface remelting (LSR) experiments. To enhance the understanding of nucleation behaviour in alloys under additive manufacturing solidification conditions, this research analyses the influence of nucleation parameters on the post-LSR microstructures. Additionally, this study explores the computational dimensions of microstructure modelling, testing CA mesh sensitivity effects and benchmarking our CAFD models on two high-performance computing platforms. The CAFD model captures well the key microstructural features observed in LSR Al-Cu alloys with and without grain refiner addition. It is shown that the maximum nucleation density has a significant effect on the final microstructure, resulting in different proportions of coarse columnar grains resulting from epitaxial solidification, newly nucleated thin columnar grains, and equiaxed grains.

This work concerns the laser wire directed energy deposition (LW-DED) additive manufacturing process. The objectives were two-fold: (1) process mapping – demarcating the process states as a function of the processing parameters; and (2) process monitoring – detecting process anomalies (instabilities) using data acquired from an in-situ meltpool imaging sensor. The LW-DED process enables high-throughput, near-net shape manufacturing. Without rigorous parameter control, however, LW-DED often introduces defects due to stochastic process drifts. To enhance scalability and reliability, it is essential to understand how LW-DED parameters affect processing regimes, and detect deleterious process drifts. In this work, single-track experiments were conducted over 128 combinations of laser power, scanning velocity, and linear mass density. Four process states were observed via high-speed imaging and delineated as stable, dripping, stubbing, and incomplete melting regimes. Physically intuitive meltpool features were used to train simple machine learning models for classifying the process state into one of the four regimes. The approach was benchmarked against computationally intense, black-box deep machine learning models that directly use as-received meltpool images. Using only six intuitive meltpool morphology and intensity signatures, the approach classified the LW-DED process state with statistical fidelity approaching 90 % (F1-score) compared to F1-score 87 % for deep learning models.

The influence of prior austenite grain (PAG) orientation on the deformation behavior of a low-carbon martensitic steel is investigated using crystal plasticity (CP) modeling with hierarchical representative volume elements (RVEs). The Kurdjumov-Sachs (K-S) relationship is refined for accurate PAG reconstruction in martensitic steel. A robust calibration strategy for CP parameters based on nanoindentation tests is developed by integrating analytical calculations with inverse methods. Virtual polycrystalline aggregates are subsequently generated by manipulating initial PAG orientations. The simulations reveal that assigning cube texture to PAGs enhances strain hardening of martensite under plane strain tension. Moreover, the RVEs with brass and copper orientated PAGs exhibit similar deformation behavior, and a more homogeneous strain distribution is realized in the RVE with PAG cube orientation. The influence of PAG orientation on stress and strain fields is correlated with lattice rotation behavior during deformation. Notably, different strain paths elicit distinct lattice rotation trajectories, wherein uniaxial tension and plane strain tension favor grains reorientation toward hard γ-fiber, whilst equi-biaxial tension drives the crystal matrix to concentrate on 〈001〉 and 〈011〉 directions. These findings provide insights into the intricate relationship between microstructural orientation and deformation behavior in martensitic steels, which is crucial for performance optimization.

Atomic-level manufacturing is fundamentally concerned with the precise removal, addition, and migration of material at the atomic and close-to-atomic scale (ACS). Tip-based electrochemical deposition, a quintessential ACS electrochemical additive manufacturing technique, offers promising prospects for achieving bottom-up fabrication of metallic micro/nano structures. However, the complex physicochemical reactions involved in electrodes lead to a limited understanding of the mechanisms underlying atomic electrodeposition and structural evolution. For the first time, this study proposes electric double-layer controlled electrochemical kinetics and investigates the effect of direct current (DC) and pulse current (PC) on nickel atomic electrodeposition using molecular dynamics (MD) simulations. The findings reveal that compared to DC electrodeposition, PC electrodeposition results in more orderly deposition morphology, improved surface smoothness, reduced dislocation density, and lower crystal distortion, with these effects being particularly pronounced under low pulse duty ratio conditions. In addition, the pulse frequency significantly influences the morphology and structure of the deposit. The high pulse frequency yields smoother surfaces with local protrusions, while the low frequency favors the formation of orderly and dense structures excepting slightly increased roughness. This study provides critical insights into understanding the microscopic mechanisms of atomic-scale electrodeposition processes and achieving atomically controlled tip-based electrochemical additive manufacturing of micro/nanodevices.

The grain preferential orientation has a significant influence on the mechanical properties of silicon nitride (Si3N4) ceramics. Based on the Jeffery’s theory, a grain rotation model under uniaxial compression is created to predict the texture evolution mechanism during sintering of Si3N4 ceramics. With deformation, the grain orientation was predicted to rotate towards the plane perpendicular to the pressure direction, and large strain was favorable for the formation of strong texture. According to guidance of the model, the weakly textured microstructure prepared by normal hot pressing is attributed to the limited strain, due to the constrains of graphite die. Therefore, a new PHIP (pseudo-hot isostatic pressing) process with the large deformation is guided to fabricate the strongly textured ceramics by promoting the grain rotation and dynamic grain growth. Generally, the experimental results are well accordance with the model prediction. Furthermore, this model could be applied to guide the design and fabrication of other isotropic and anisotropic ceramic materials.

Mechanical properties of additively manufactured alloys are momentously affected by the fabrication defects, thus limiting their applications in extreme conditions. Here we report on a near fully dense 316L stainless steel via optimized laser processing parameters. The results reveal that the dynamic mechanical response exhibits much greater sensitivity to defects than the quasi-static one. The densest specimen (porosity

Effective UV protection is a key aspect of substrates directly exposed to UV radiation. Therefore, in the present study, fibrous substrates of core–shell morphology (PCL-core, PVP-shell) containing peptides based on tryptophan, tyrosine and cysteine (W6, YYC2 and YYC3) were prepared. Spectrophotometric studies showed UV absorption by peptides containing tyrosine and tryptophan in the UVB (up to 80%) and UVA (up to 40%) ranges. Cysteine, in turn, contributed to high antioxidant properties, confirmed by DPPH assay. The presence of peptides contributed to a nonwoven fabric characterized by the ability to absorb UV radiation and prevent the occurrence of oxidative stress (caused by the presence of free radicals). In turn, the increase in the surface zeta potential of the nonwoven after UV irradiation and higher thermal stability (demonstrated by DSC studies) indicated the crosslinking of the PVP layer under UVR, which further contributes to the increased protection of the nonwoven against its effects. In summary, obtained nonwoven exhibited functional similarity to the native cornea, providing a potential solution for enhancing corneal tissue engineering and regenerative medicine applications.

The treatment of breast cancer (BC) remains a significant challenge, exemplified by the limitations of chemotherapy due to its high side effects. Light-responsive drug delivery systems (DDS) offer a promising approach to spatially and temporally release drugs, minimizing chemotherapy side effects and enhancing efficacy. However, achieving precise delivery and site-specific drug release poses complex challenges. Here, We present a novel nano-system combining light-responsive photothermal therapy (PTT) with photothermal-responsive chemotherapy via π − π Stacking. Conjugated polymer nanoparticles (cRGD-PTer N25/CPT NPs) is designed for spatiotemporal targeted PTT/chemotherapy. Research shows that the strong near-infrared absorption of PTer N25 endows cRGD-PTer N25/CPT NPs with excellent photothermal capabilities(57.4 %) and near-infrared laser-triggered drug release performance. The cRGD-PTer N25/CPT NPs enhanced BC-specific cellular accumulation, prolonged blood circulation, exhibited good biocompatibility, and improved PTT and chemotherapy efficacy in BC cell lines and mouse models while reducing systemic toxicity. The photothermal effect triggered the on-demand release of camptothecin (CPT), producing therapeutic effects and downregulating heat shock protein 70 (HSP 70), reducing cancer cell thermoresistance, and enhancing combined treatment efficacy. Under spatial and temporal control, the tumor growth inhibition rate of the cRGD-PTer N25/CPT NPs group reached 93.6 %, nearly eradicating tumor presence, whereas the control group exhibited only partial inhibition. Minimal cardiotoxicity and metastatic side effects are not observed. This work presents a viable strategy for designing novel controlled-release drug systems to improve breast cancer treatment efficiency.

This work introduced the effects of higher tempering temperatures on the microstructural evolution of Cu − bearing medium Mn steel. After quenching steel at 860 °C for 1 h, it was tempered at 600, 640, and 670 °C for 2 h. The results indicated that the low − temperature impact toughness initially increased and then decreased, while the yield strength consistently decreased with increasing temperature. At a tempering temperature of 640 °C, the steel exhibited a relatively high content of reversed austenite and demonstrated the best low − temperature toughness and plasticity. The low − temperature toughness and plasticity of the steel significantly diminished, when the temperature exceeded 640 °C. This is because the degree of alloying element enrichment in the reversed austenite is reduced, accompanied by an increase in dislocation density and the formation of twins. These reversed austenites exhibit a diminished ability to hinder crack nucleation and propagation. The yield strength decreased with increasing temperature, primarily due to the coarsening of the Cu particles, which reduces their precipitation strengthening effect. This study advances the development of high − strength tough medium − manganese steels.

Infection and poor osteogenesis are two major causes of implant failure. Surface modification strategy provides solutions to the above problems. However, the functional requirements at different biological stages during infectious bone repair and the oxidative stimulation caused by reactive oxygen species (ROS) in an inflammatory environment pose challenges to the existing approaches. Layer-by-layer (LbL) self-assembly realizes layer by layer superposition and time-dependent acting of different bioactive components, but is demanding to functional groups. Tannic acid (TA) owns abundant phenolic hydroxyl groups, endowing various firm chemical bindings and excellent antioxidant property. To this end, we developed a time-dependent and antioxidant multifunctional coating via TA mediated LbL self-assembly. This layer exhibited higher ROS removal capacity and stronger binding ability. Furthermore, it showed rapid and excellent antibacterial ability of over 85 % against Staphylococcus aureus and Escherichia coli at 24 h, which additionally promoted osteogenic differentiation in vitro in long term. Moreover, the coating exhibited outstanding antibacterial and bone regeneration performance in vivo as well. Thus, this study is expected to provide an antioxidant and time-dependent multifunctional platform for surface modification engineering of dental and orthopedic implantation, as well as other potential biological material designs.

A novel type of nanocomposite Zr–Cu–N material based on hard nanocrystalline ZrN and amorphous glassy ZrCu was prepared by atom-by-atom deposition using reactive magnetron co-sputtering. The elemental composition of the coatings was systematically controlled over a wide range, so that the stoichiometry of both phases was the same in all coatings and only phase fractions varied. Experimental results obtained using X-ray diffraction and electron microscopies were complemented by thirteen ab-initio simulations for the same coating compositions. We found that the structure of the as-deposited Zr–Cu–N coatings undergoes a gradual transition from an amorphous to nanograined and finally to nanocolumnar structure. When ZrN fraction exceeds 20 mol.%, both phases exhibit the tendency for spontaneous segregation even without heating, forming a heterogenous dual-phase nanocomposite structure. At approximately 50 mol.% ZrN, the ZrN nanocrystals enveloped by a relatively thin amorphous ZrCu phase reach an optimum size (3–5 nm), resulting in a maximum enhancement of hardness by 38 % compared to the rule of mixture. For ZrN fractions > 80 mol.%, hardness and plastic work fraction follow the trend proposed by the rule of mixture and the coatings with a lower hardness but a higher plasticity compared to the ZrN coating are prepared.

The tensile properties of 2219-T8 aluminum alloy TIG welding joint were significantly affected by the microstructure, local mechanical properties and weld geometry. This paper proposed a machine learning model to predict and optimize the tensile properties of 2219-T8 aluminum alloy TIG welding joint. The relationship between tensile strength of joint and weld geometry, weld zone and partially melted zone (PMZ) properties was developed by Kriging model combining whale optimization algorithm (WOA). This surrogate model demonstrated a high precision, with R2 = 0.952 and RMSE=3.77 MPa. The surrogate model, which also served as a welding process guide, was utilized to determine the ideal weld geometry corresponding to various weak zone properties. By applying the optimization process based on the surrogate model, the optimized joint strength coefficient reached 70 %, and elongation exceeded 4 %. The collaborative regulation mechanism of geometry and property was also discussed.

Herein, we systematically explored how to tailor heterogeneity in the Ni-Nb-(Y, Gd) phase-separated metallic glasses (PSMGs) by carefully constructing a metastable miscibility gap and investigating its effect on the formation of heterogeneous shear band (SB) nucleation sites. The Ni60Nb40-x(Y, Gd)x PSMGs with either Nb-Y or Nb-Gd atomic pair (ΔHmix=+30 kJ/mol) showed hierarchically phase-separated microstructures at the nanoscale, which can be interpreted based on a metastable miscibility gap. Interestingly, statistical analysis of the initiation of plastic deformation via nanoindentation first pop-in analysis in these PSMGs reveals a unique trimodal distribution, unlike the bimodal distribution in monolithic MGs. This tendency arises from the formation of nanoscale phase boundaries as additional differentiated heterogeneous SB nucleation sites. The homogenously dispersed SB nucleation sites help hinder strain localization and SB propagation. In particular, a PSMG with a nanoscale interconnected structure exhibits homogeneous-like plastic deformation, where neither obvious pop-ins nor distinct surface shear steps are observed in the (nano-)indentation test. We believe this study's results provide an effective guideline for tuning correlative heterogeneity and related mechanical responses in PSMGs, highlighting the importance of tailoring microstructure even in MGs.

The exponentially large compositional space of high entropy alloys (HEAs) offers more possibilities for designing alloys with desired properties. However, it also poses challenges to using the traditional “trial and error” approach in alloy design. In this work, an XGBoost model for predicting the elastic properties of the NbTiVZr family across the entire compositional space was established by combining density-functional theory (DFT) calculation results as the dataset with machine learning (ML) algorithms. Furthermore, considerations of charge transfer were incorporated into the solid solution hardening (SSH) model, and the model was further modified. Through comparing plasticity evaluation indices, the parameter D (γSurf/γGSFE) was determined to be suitable for predicting the plasticity of NbTiVZr alloys. A full compositional space model for yield strength and plasticity has been constructed based on the modified SSH model and the parameter D, respectively. Ultimately, an alloy design system combining the full compositional space models for yield strength and plasticity was established, achieving good consistency with experimental results. And a non-equiatomic alloy with a yield strength exceeding that of equiatomic alloys by 32.2 % (1409 MPa), while maintaining 29.27 % compressive strain was discovered. In conclusion, this work provides an efficient design strategy for alloys with desired properties.