Search

Inspired by the emerging field of twistronics, moiré photonic structures have attracted great interest. In this paper, we introduce the concept of the moiré Kagome lattice (MKL), which arises from the overlapping of a Kagome lattice at a commensurable angle of 38.211°. MKL exhibits a significantly broader main photonic bandgap (PBG) when compared to the traditional Kagome lattice. Through numerical simulations, we delved into the adjustable properties of the PBG of MKL by varying lattice parameters, including filling factors and materials. Meanwhile, we also observed the presence of photonic flatbands within the MKL structure. Specifically, the emergence of a super flat isolated flatband aids in achieving single-mode omnidirectional lasers and enhancing the omnidirectional electromagnetic interaction of materials, thereby expanding the applications of moiré photonic crystals. [ABSTRACT FROM AUTHOR]

The mechanical properties of models are crucial in determining the industrial applications of additive manufacturing techniques. Material jetting (MJ) has been primarily limited to mold-making, prototyping, etc., owing to its low strength. Low viscosity and rapid curing, which are essential ink characteristics of MJ, lead to the low strength of MJ models. This study aimed to develop methods to increase the strength of MJ models by adding fillers to the ink. We optimized the shape and size of the filler, modified the surface properties, and optimized the methacrylate monomer formulation of the ink. To develop a colorization process suitable for filler-added inks, we investigated a method to apply transparent ink over small-colored ink droplets. We achieved a bending strength of 180 MPa for colorless models and 177 MPa for colored models, which is remarkable compared to the typical MJ product strength of 90 MPa or less. These findings clarify the design guidelines for high-strength MJ ink, making the direct manufacturing of production parts requiring both esthetic beauty and high strength in colors, such as artificial teeth, dentures, and eyeglass frames, more realistic. [ABSTRACT FROM AUTHOR]

The effect of bedding cohesion and loading conditions on the bolting behavioral characteristics of a bedded rock mass was investigated using a self-developed artificial material and loading system. First, physical samples with dimensions of 15 cm × 15 cm × 8 cm containing both the grout and gypsum layers were prepared. The ratio of the thickness of the grout layer to the gypsum layer was 0/100, 25/75, 50/50, 75/25, and 100/0. One grouted bolt was situated in the middle of the sample. Two types of filling materials were chosen as a filling segment around the rock bolt, i.e., gypsum and grout. The tensile strengths of gypsum and grout were 1.4 and 2.4 MPa, respectively. The length and diameter of the bolt were 12 and 2 cm, respectively. The grout dimension was 5 cm × 5 cm × 8 cm. These samples were tested under two different axial loading conditions. A total of 20 distinct tests were conducted concurrently with laboratory experiments utilizing Particle Flow Code in Two Dimensions. The loading rate was 0.05 mm/s. The findings revealed a strong correlation between breakage patterns and loading conditions. Moreover, it was observed that the grout filling significantly impacts the ultimate axial load compared to gypsum filling. When loading the interface between the rock bolt and the filling segment, the final axial load remained consistently similar across all filling types. Notably, the grout filling resulted in a notably higher final axial force. The variation in grout and gypsum bedding layer thicknesses did not demonstrate any discernible effect on the final axial load. Conversely, when loading the interface between the filling and bedding layers, an increase in grout layer thickness led to an augmented final axial load. The grout filling segment also contributed to a heightened final axial force. The results of the numerical simulations exhibited a commendable agreement with the experimental outputs. This research effectively addresses two critical aspects: stability control and support design for the bedded rock mass. Practical Applications: This study used a unique artificial material and loading system to investigate how bedding cohesion and loading conditions affect bolting behavior in rock mass. The findings showed a significant difference in ultimate axial load when grout was used compared to gypsum filling around the rock bolt, emphasizing the importance of this factor in stability control. The research revealed a strong connection between breakage patterns and the specific loading conditions applied, providing valuable insights into support design in a bedded rock mass. The study also demonstrated a high level of agreement between experimental and numerical simulations, strengthening the credibility of the findings and their relevance to real-world stability control measures. [ABSTRACT FROM AUTHOR]

Load transfer platform (LTP) plays an important role in load transfer between piles and subsoil in pile-supported embankments over soft soils. This study conducted spring-based trapdoor tests to investigate the load transfer mechanisms of LTPs with unreinforced and geosynthetic-reinforced river sand and lightweight aggregate (LWA) subjected to differential movement. Spring-based trapdoor tests were used to simulate the differential movement below the LTP under fill placement and surface footing loading to investigate the mobilization and degradation of soil arching and tensioned membrane effects above the trapdoor (simulating the subsoil settlement). To evaluate the trapdoor rigidity effect, both rigid (one-segment) and flexible (three-segment) trapdoors were utilized. Test results revealed that LWA, when utilized as an LTP material, could effectively improve the mobilization of soil arching, hinder the degradation of soil arching, and reduce the trapdoor settlement. LWA was proven to be a good alternative LTP fill material in pile-supported embankments. Geosynthetic reinforcement was beneficial to minimize degradation of soil arching. In the rigid trapdoor tests, the tensioned membrane effect was progressively mobilized with the applied footing pressure. However, the flexible trapdoor tests showed rapid mobilization of the tensioned membrane effect, followed by a sustained mobilization, and then a rapid arching degradation after a certain applied pressure was reached and continued. Under surface footing loading, the embankment with the LWA as the LTP fill material showed an inverted tower-shape deformation pattern, whereas that with the river sand as the LTP material exhibited a rectangular deformation pattern. [ABSTRACT FROM AUTHOR]

Ground-borne vibrations generated by various man-made activities pose a perennial threat to nearby buildings, impacting their serviceability and causing annoyance to residents. This study addresses the pressing demand for cost-effective and environmentally friendly materials capable of effectively mitigating such vibrations using bamboo-filled trenches. A series of field-scale vibration tests are conducted to investigate the near-field and far-field vibration screening behavior of bamboo-filled trenches (BT) and open trenches (OT). Two different configurations of BT are used for the current investigation. The influence of input frequency, source–trench distance, and trench configuration on the screening response of BT and OT is evaluated using field-scale vibration tests. The findings obtained from this study suggest that the efficacy of BT in near-field and far-field screening is satisfactory. It can be noticed that BT and OT are more effective in mitigating vibrations at higher frequencies. For near-field screening, the source–trench distance significantly influences the screening behavior of OT at lower frequencies, while the performance of BT is not significantly influenced. The efficacy of BT and OT is higher along the centerline than other angular lines emerging from the source. Near-field and far-field screening behavior of BT and OT is seen to differ significantly. In the screening process, the isolation efficacy of BT decreases as the volume of bamboo increases. Practical Applications: The suitability of different types of wave barriers for mitigating unwanted ground-borne vibrations has drawn substantial attention from researchers. However, the utilization of natural and cost-effective filler materials for mitigating such vibrations remains scarce. In this regard, the present study introduces bamboo as a novel filler material for protecting essential structures from the detrimental effects of ground-borne vibrations. BT offer a wide range of practical advantages, such as cost-effectiveness, ecofriendliness, and ease of installation, dismantling, and reinstallation. Furthermore, BT overcome the limitations associated with OT, such as sloughing, sand pockets, and collapse, while effectively mitigating induced vibrations. The proposed technology will be of particular interest to construction industries, housing societies, and urban area residents affected by ground-borne vibrations generated from different activities. [ABSTRACT FROM AUTHOR]

Biodegradable aerogels possessing flexibility and high strength are appealing for applications in construction, acoustic and thermal insulation. However, their susceptibility to flammability presents a significant challenge. Enhancing the flame retardancy of these aerogels has been a prominent focus of research, with the widespread use of inorganic fillers and layered materials for this purpose. In the current study, our objective is to fabricate cellulose nanofiber aerogels characterized by low density, exceptional flame retardancy, high mechanical properties, and thermal insulation. This is achieved through the cross-linking of melamine and formaldehyde under aqueous conditions using an eco-friendly freeze-drying process, followed by post-curing. The resulting aerogels demonstrate flexibility, effective sound absorption within the mid-frequency range, and outstanding flame retardancy (Limiting Oxygen Index ∼33%) with a non-flammable behaviour. The thermal conductivity of the fabricated melamine formaldehyde-modified cellulose nanofiber (MF-CNF) aerogels was 0.064 ± 0.014 W/m.K. MF-CNF aerogels exhibited a Time to Ignition (TTI) of 489 s, whereas pristine CNF aerogels only have 3 s. This improvement was attributed to the concurrent reductions in both the Peak Heat Release Rate (PHRR) and Fire Growth Rate (FIGRA) of MF-CNF aerogels. The straightforward melamine formaldehyde modification of CNF aerogels enhances their mechanical strength as well as fire resistance. These sustainable multifunctional aerogels hold great potential for a variety of real-life applications in the realm of buildings and its structures for ensuring fire safety and sound insulation. [ABSTRACT FROM AUTHOR]

Rock-filled concrete (RFC) construction technology is to construct a force-transferring skeleton with large-size rocks, and to use self-compacting concrete (SCC) as the filling and bonding material. In which the defects with different distributions and sizes contained in SCC are often the key factors determining the mechanical properties and damage behaviors of RFC. In this research, by utilizing the excellent properties of super absorbent polymer (SAP), such as water absorption and expansion and dehydration shrinkage, non-introduction of impurities, and not easy suspension or settlement in concrete, RFC and SCC specimens with different numbers and sizes of defects were precisely prepared and subjected to unconfined uniaxial compression physical tests. The effects of porosity and pore aperture on the compressive strength and damage pattern of the specimens were studied. The mechanical behavior of the defective concrete specimens under compressive loading was analyzed from a mesoscopic perspective by using a combination of physical tests and numerical simulation using the Realistic Failure Process Analysis (RFPA) method to reveal the internal damage phenomenon and damage destabilization mechanism of RFC and SCC. The results show that: SAP material can accurately construct concrete specimens with stable and uniform defects; under the same porosity and aperture, the compressive strength of RFC is greater than that of SCC; the compressive strength of the specimen decreases linearly with the growth of porosity for the same aperture, the compressive strength of the specimen decreases with the increase of aperture for the same porosity and the trend tends to be flat, and the sensitivity of the compressive strength to porosity is higher than that of aperture. In addition, it was found that the internal penetrating shear damage during the fracturing process of SCC was the core cause of the overall damage. For RFC, the tensile fracture that penetrated through the force transmission skeleton of the stacked rock was the key factor causing the overall instability. [ABSTRACT FROM AUTHOR]

The development of eco-friendly materials is a challenging one in the research field. Natural fibers are more accessible, biodegradable, inexpensive, and less dense. They offer fewer health risks and are eco-friendly compared to synthetic fibers. Natural fiber-reinforced polymer composites are new, eco-friendly materials with excellent mechanical and practical applications. Adding biofillers to composites improves strength and will replace synthetic materials. Utilizing cellulose as a filler for a natural starch matrix is an effective way to reduce the environmental impact of non-biodegradable materials. This study covers the influence of natural Borassus flabellifer flower microcrystalline cellulose (BFF MCC) fillers on banana fiber-reinforced polymer matrix composites. Fourier-transform infrared spectroscopic peaks at 2357, 1730, and 1245 cm-1 were absent. This indicates that the amorphous proportion of banana fiber mat/BFF MCC-reinforced hybrid composites decreased. At 1% BFF MCC, thermogravimetric examination revealed an increase in the peak temperature of maximum degradation (389.6 °C). The hybrid banana composite's tensile strength (31.36 ± 4.39 to 39.83 ± 3.07 MPa) and flexural strength (71.05 ± 2.66 to 82.4 ± 1.66 MPa) were also improved after adding 3% BFF MCC as filler material. The primary objective is to evaluate the suitability of fiber-reinforced hybrid polymers with natural fillers for future engineering applications such as automotive parts, construction materials, 3D printing, etc. In addition, this study investigated how the reinforcement of microcrystalline cellulose can result in a material with enhanced performance as well as its mechanical characteristics (XRD, FTIR, TGA, and SEM characterization). [ABSTRACT FROM AUTHOR]

Cold-finished carbon steel bars were bonded by means of the transient liquid phase bonding (TLPB) process using amorphous metallic foils of the eutectic Fe-B composition as filler material. A homogeneous microstructure throughout the joint was obtained. Traces of borides in the middle of the joint were the only distinguishable microconstituent from the base metal due to the TLPB process. The B concentration profile across the joint was measured by neutron radiography and was found to be composed of a central sharp peak with a maximum concentration of 15.9 ppm B superimposed over a broad peak (base width of ≈ 5 mm) with a maximum concentration of 13.3 ppm B. Owing to this low range of B concentrations, boride precipitation was almost suppressed, and only a scarce number of borides were observed at the joint. The resulting boride structure was identified as Fe23B6 by synchrotron microfocused X-ray diffraction, and its stabilization at room temperature is discussed. The bonded samples were subjected to a bend test, with a bending angle of 180°, and no cracks were observed. In tension tests, the bonded samples attained an ultimate tensile strength (UTS) of 434 MPa, an elongation of 32.3% and a reduction area q of 51.2%—78.6%, 165.6% and 75.4%, respectively, of the base metal. The fracture of the bonded samples occurred at the joint. It was determined that the decrease in UTS compared with that of the base metal was due to the recovery, recrystallization and grain growth that occurred during the TLPB thermal cycle. In addition, from fracture surface observation, it was found that the decrease in q in bonded samples was caused by the presence of traces of borides at the joint, which were the result of the liquid phase that solidified during the cooling stage. [ABSTRACT FROM AUTHOR]

This study aims to investigate the mechanical, thermal, morphological, and characterization properties of a polymer composite composed of water hyacinth plant fibres. In order to improve the mechanical properties of the composite specimens, a new powder derived from the moringa plant was used for the first time as a filler material in the water hyacinth plant-reinforced polymer composites. In this study, composite specimens were prepared using a hot compression moulding machine. The weight percentage of moringa resin filler powder and hyacinth fibre was varied during the process from 2.5 to 7.5% and 15 to 35%. The resulting tensile strength ranged from 18.24 MPa to 32.14 MPa, flexural strength ranged from 38.64 to 56.32 MPa, impact strength ranged from 1 to 3.75 J, and hardness ranged from 66 to 98 Shore D hardness. The composite sample containing 5% moringa filler powder and 30% WH fibre content achieved high mechanical strength, maximum decomposition temperatures, and high crystallinity percentages. It exhibited 11–13% higher strength compared to the other samples. Absorption studies showed weight gains of 3.42% and 4.45% for water and chemical absorption, respectively. The fracture surfaces of the composite specimens were analysed using the SEM technique. The fabricated composites could be useful for particle board and medium density fibre board applications. [ABSTRACT FROM AUTHOR]

Lightweight porous structural materials have excellent energy absorption performance, and their application are gradually appeared. This paper takes the shock-absorbing material of nuclear equipment transportation casks as the starting point, and manufactures an orthogonal trapezoidal aluminum honeycomb by welding (WOTAH). The mechanical properties with different cell thicknesses and cell size ratios under different impact loads are studied through experimental and simulation methods, and the deformation process and energy absorption performance of the materials are obtained. The energy absorption performance of materials under quasi-static loading was investigated using plastic deformation theory and compared with experimental results. Based on the experimental results, the least squares method was used for data fitting to obtain the C-S dynamic constitutive relationship of the material. The equivalent structure was used to replace the honeycomb structure for simulation, and the influence of strain rate effect and structural size on material properties was further studied. Through the above mechanical performance analysis and comparison with wood, it is shown that WOTHA has feasible for the application of nuclear equipment impact limiter. [ABSTRACT FROM AUTHOR]

Translation abstract Numerical investigations for the definition of box‐type cofferdamsCofferdams in cell and box form serve as temporary structures for enclosing large excavation pits or as permanent structures for bank reinforcements and breakwaters. Box cofferdams consist of two mutually anchored and parallel sheet pile walls, with fill material in between. Box cofferdams are often subjected to unilateral loads and are designed to withstand large horizontal forces such as water pressures, impact loads, or earth pressures. The recommendations of the Working Committee on Bank Reinforcements [1] provide guidelines for the design of cofferdams, primarily based on the studies by [2]. In the stability verification of box cofferdams, according to [1], it is assumed that a compact soil block exists between the opposing cofferdam walls. However, [1] does not explicitly define when two opposing walls are considered a box cofferdam structure. To define the applicability ranges for box cofferdams, extensive numerical investigations in the serviceability state were carried out for this article. [ABSTRACT FROM AUTHOR]

Background and Objectives: Diffusion of hydroxide (OH)− and calcium (Ca)++ ions through dentin may cease external root resorption. Calcium hydroxide (Ca(OH)2), mineral trioxide aggregate (MTA), and calcium‐enriched mixture (CEM) cement are the choices for this purpose due to their optimal properties. This study sought to analyze the effects of ultrasonic activation (UA) on pH and the release of calcium ions from Ca(OH)2, MTA, and CEM cement in external root resorption artificial defects. Materials and Methods: This in vitro research involved the instrumentation and shaping of the root canals of 150 single‐rooted teeth (#F4). External defects were intentionally made on the middle one‐third of the root surface. Teeth were randomly assigned to a negative control group (n = 10), one positive control group (n = 20), and six experimental groups (each n = 20) according to the root canal filling material (Ca(OH)2 paste, MTA, CEM, gutta‐percha, Ca(OH)2 paste+ultrasonic, MTA + ultrasonic, and CEM + ultrasonic). Ultrasonic energy was transferred to the test materials using a #25 spreader. Ca++ concentration and pH were measured after 1, 7, 15, and 30 days in all groups. Statistical analysis involved the use of repeated measure analysis of variance (ANOVA) and paired‐sample T‐test (P ≤ 0.05). Results: The levels of calcium ions and pH increased significantly over time in all groups (P < 0.001). There were significant differences between the experimental groups in terms of pH and the concentration of released calcium ions at different times (P < 0.001). The Ca(OH)2 plus ultrasonic energy group ranked first, while the gutta‐percha group ranked last in terms of release of calcium ions and pH. Conclusion: The Ca(OH)2, MTA, and CEM cement groups showed an increase in pH and the release of calcium ions at the external root resorption defects. Additionally, the application of ultrasonic energy increased the release of calcium ions at these sites. [ABSTRACT FROM AUTHOR]

Polytetrafluoroethylene (PTFE) is widely used in tribological applications. However, it faces challenges due to its high wear rate. Reinforcement of additives in PTFE reduces its wear rate by up to 10,000 times in dry conditions. Infusing metallic filler materials like Al, Cu, and Pb improves PTFE wear performance but increases the coefficient of friction (COF). However, it may not be suitable for corrosive environments due to potential metal reactivity. Reinforcing PTFE composites with carbon‐based materials reduces weight, improves wear properties, and lowers COF. Pre‐treated materials enhance bonding for improved anti‐friction and anti‐wear properties. PTFE and its composites are widely used in journal bearings, bearing pads, and ball bearings due to their excellent low‐speed, low‐load lubrication properties. They outperform Babbitt alloy in bearing pads, except in heat conductivity. PTFE can also be used as a solid lubricant and can be combined with additives for improved performance. Apart from it, achieving an optimal combination of properties for all forms of reinforcement can be challenging due to the difficulty in determining exact values for multiple properties with specific types of reinforcement. This article provides a comprehensive review that delves into the significant findings pertaining to reinforcement and its application in bearing technology. Highlights: Metals and carbon‐based fillers improve tribo‐properties.Polytetrafluoroethylene (PTFE) provides lubrication and thermal stability to the polymeric materials.Estimation of tribo‐thermal properties in combination is a challenge.Testing conditions greatly impact PTFE composites performance.PTFE as a solid lubricant suitable for low‐speed/load applications. [ABSTRACT FROM AUTHOR]

Lightweight concrete, particularly polystyrene concrete, has been extensively utilized in civil engineering for decades. The incorporation of waste expanded polystyrene (EPS) as a filler material in the production of lightweight concrete presents significant advantages from a circular economy perspective. Prior research indicates that increasing the proportion of lightweight aggregates, such as EPS, typically results in reductions in strength and bulk density. The utilization of substantial amounts of EPS waste in the formulation of structural polystyrene concrete is crucial for advancing sustainable construction practices. This study investigates the effects of varying nano-silica content on the bulk density, compressive strength, flexural strength, splitting tensile strength, and water penetration depth of structural polystyrene concrete. Concrete specimens were prepared by substituting 25%, 50%, 75%, and 100% of sand with EPS waste, while evaluating nano-silica contents of 0.75%, 1%, and 1.25%. The findings reveal that increasing the volume fraction of EPS corresponds to a decrease in the concrete's bulk density. This research provides critical insights into optimizing structural lightweight concrete, thereby promoting advancements in sustainable construction applications. [ABSTRACT FROM AUTHOR]

In the present study, a method is proposed for preparing novel ductile‐sticky materials that can be used as bone void fillers using hydrolyzed wool‐keratin (WK) and silk fibroin (SF). This methodology uses citric acid as a cross‐linking agent in preparing keratin paste (KP) owing to its non‐toxicity and plasticizing properties. The Keratin paste‐silk fibroin structure (KPSF) is obtained by adding SF, which possesses biocompatible and superior mechanical properties. Methanol treatment is employed on the KPSF mixture to convert the Silk I structure in the SF to Silk II, resulting in a water‐insoluble and tightly packed proteinaceous structure. The physicochemical properties of both bioscaffolds are investigated and discussed in detail by comparison. Based on the findings, the presence of SF in the KPSF structure contributed to properties such as flexibility and porosity. In ovo CAM analysis reveals that both materials exhibit proangiogenic properties and are biocompatible. KP and KPSF bioscaffolds can be converted into ductile‐sticky forms by adding water. It believes that these forms can easily apply to bone defect areas, particularly cavitary bone defects. Furthermore, KPSF bioscaffolds, with better mechanical properties, can be considered candidates for use in non‐load‐bearing bone tissue engineering applications. [ABSTRACT FROM AUTHOR]

The three stages of loess collapse are characterized by notable concealment and sudden onset due to the sudden nature of loess collapse and the prolonged duration of the peristaltic deformation stage. Traditional displacement monitoring methods struggle to detect early signals of instability and failure, leading to poor timeliness in disaster warnings. This project begins by examining non-force field information related to the loess collapse process. It focuses on acoustic emission monitoring and employs model tests to identify effective waveguide rods for monitoring loess collapse. Additionally, the project investigates the evolution anomalies of acoustic emission parameters before and after loess collapse failure, aiming to establish early warning criteria for loess collapse based on acoustic emission. This work provides a theoretical basis for monitoring and early warning of loess collapses. This study evaluates five parameters of the active waveguide system: sensor installation method, filling material, waveguide rod wall thickness, outer wrapping material, and outer wrapping wall thickness. The densities of the filler materials were tested using the optimal parameters derived from the tests to identify the best configurations for active acoustic emission (AE) waveguide systems suitable for monitoring loess collapse. Subsequently, a one-sided connected loess collapse model was employed for indoor tests, integrating real-time AE monitoring with the active waveguide method. This model facilitates the exploration of AE response characteristics during loess collapse and the analysis of destructive forms of loess collapse and time-sequence evolution of AE ringing counts throughout the deformation and destruction process. Results indicate that using filler materials with high elasticity modulus, high compactness, and low Poisson's ratio, along with thin outer wrapping and waveguide rod walls, leads to strong AE signals. As deformation damage of loess collapse intensifies, the number of AE ringing counts notably increases. A rapid rise in cumulative ringing counts can indicate a "sudden increase", or the b-value may stabilize, providing precursor information for loess collapse. [ABSTRACT FROM AUTHOR]

Welding is a crucial process in joining metals, especially in the fabrication industry. Thisresearch aimed to investigate the effects of using two different filler materials, ER70S-6 and ER308LSi, with nine combinations of wire feeder speed (WFS) and shielding gas flow rate (GFR), on weld joints. The study focused on the weld quality and material properties of Gas Metal Arc Welded (GMAW) butt joints of ASTM A516 G70 plates, characterized through visual inspection, liquid penetrant testing, tensile testing, hardness testing, and optical microscopy. Results indicated that the highest ultimate tensile strength and hardness were achieved at 4 m/min WFS and 15 L/min GFR with ER70S-6, and 5 m/min WFS and 20 L/min GFR with ER308LSi. The specimens welded with ER308LSi demonstrated superior mechanical properties compared to those welded with ER70S-6. Additionally, the study revealed the influence of microstructural changes from the base metal (BM) to the heat-affected zone (HAZ) and fusion zone (FZ), with finer and more compact grain structures contributing to higher hardness values. These findings underscore the importance of selecting appropriate filler materials, WFS, and GFR to achieve the desired weld quality and material properties for A516 G70 low-carbon steel welded joints. [ABSTRACT FROM AUTHOR]

Lattice structures, characterized by their repetitive, interlocking patterns, provide an efficient balance of strength, flexibility, and reduced weight, making them essential in fields such as aerospace and automotive engineering. These structures use minimal material while effectively distributing stress, providing high resilience, energy absorption, and impact resistance. Composed of unit cells, lattice structures are highly customizable, from simple 2D honeycomb designs to complex 3D TPMS forms, and they adapt well to additive manufacturing, which minimizes material waste and production costs. In compression tests, lattice structures maintain stiffness even when filled with powder, suggesting minimal effect from the filler material. This paper shows the principles of creating finite element simulations with 3D-printed specimens and with usage of the lattice structure. The comparing of simulation and real testing is also shown in this research. The efficiency in material and energy use underscores the ecological and economic benefits of lattice-based designs, positioning them as a sustainable choice across multiple industries. This research analyzes three selected structures—solid material, pure latices structure, and boxed lattice structure with internal powder. The experimental findings reveal that the simulation error is less than 8% compared to the real measurement. This error is caused by the simplified material model, which is considering the isotropic behavior of the used material PA12GB (not the anisotropic model). The used and analyzed production method was multi jet fusion. [ABSTRACT FROM AUTHOR]

Laser welding was performed using different filler wires, ER70S steel, commercially pure iron, and pure nickel filler, in the context of welding X80 pipeline steel to assess the microstructure and mechanical properties of the weld metal. Introducing an ER70S wire promoted acicular ferrite formation in the fusion zone, compared to a bainitic microstructure in an autogenous laser weld. The use of pure iron wire was considered as a potential strategy for reducing hardenability, as it led to the dilution of alloying elements in the fusion zone, increasing ferrite content and reducing weld metal hardness to a level compliant with API pipeline standards. The addition of pure nickel wire was used to reveal the degree of weld metal mixing imposed by the laser (thus providing an unambiguous tracer element) when it is combined with filler material dilution in the fusion zone, revealing that the upper region contained 38% wire material and the lower region only 12%. This accounts for the differences observed between the upper versus lower portions of the weld metal when other wires are used, and the use of hardness mapping and micro-indentation demonstrates the correlation between the variations in mechanical properties and microstructural differences introduced by incomplete mixing of the filler wire elements. [ABSTRACT FROM AUTHOR]

The extraction of mining resources, as well as processing processes such as ore beneficiation and smelting, generate large amounts of tailings that are difficult to directly utilize. Meanwhile, substantial filling materials are required for the voids formed after mining operations, and the environmental issues and safety hazards brought on by massive solid waste disposal cannot be ignored. By utilizing solid waste with alkaline and pozzolanic activity as the binder component and gold tailings as filler aggregate to prepare filler material to fill up the void areas, the purpose of waste treatment can be achieved. In this study, salt sludge, steel slag, ground granulated blast furnace slag, and gold tailings were used to prepare all-solid waste fluidized filling material for filling mine void areas, which not only solves the engineering safety problem of easy collapse of the mine airspace in the mining process but also ensures a backfill effect with high strength, which continuously guarantees the uninterrupted progress of the mining project. At the same time, the preparation of fluidized materials can consume a large amount of tailings and other solid waste, solving the problem of their stockpiling. The components of the solid wastes used are all general industrial solid wastes, so the preparation of the fluidized materials will not have an impact on the surrounding environment. The effects of binder ratios on the workability of the filling materials were investigated by means of the slump and slump flow tests. Combined with the unconfined compressive strength test, the change in backfill material strength with curing age and the water–binder ratio was studied. The experimental results showed that the slump and slump flow value of the filling material were positively correlated with the water–binder ratio. The water–binder ratio range satisfying a slump value of 180~260 mm and a slump flow value not less than 400 mm was 0.95~1.106. However, the strength decreased with the increase in the water–binder ratio, conforming to a hyperbolic relationship. The all-solid waste fluidized filling material had strengths not less than 0.22, 1.09, and 1.95 MPa at 3, 7, and 28 d, respectively, meeting the workability requirements. Finally, a method for determining the optimal range of water–binder ratio considering both workability performance and strength is proposed based on the relationship between slump value, slump flow value, unconfined compressive strength, and the water–binder ratio. [ABSTRACT FROM AUTHOR]

The performance of fly ash blended concrete is influenced by the pozzolanic and/or micro-aggregate effect of fly ash particles based on the replacement levels. Dominance of either of this effect greatly influences the mechanical and fracture properties of fly ash blended concrete. In view of this, in the present study, 0%, 20%, 30%, 35%, 40%, 50%, 60% and 70% of fly ash is replaced for cement to investigate the dominance of pozzolanic or micro aggregate effect. The results obtained from the study indicate the reduced strength with increased replacement of fly ash. Similarly, the peak load at fracture decreases with the increased replacement of fly ash. Further, it is concluded that with the increased curing age the compressive strength increases and the fracture strength decreases. Furthermore, the decreased content of calcium hydroxide (CH) with increased fly ash content as obtained from thermo gravimetric analysis (TGA) confirms the presence of excessive fly ash that can contribute as filler material demonstrating the micro-aggregate effect. [ABSTRACT FROM AUTHOR]

Engineering rock masses typically feature natural discontinuities that span different scales, with filled joints as macroscopic discontinuities and microdefects as mesoscopic ones. However, the mechanism of wave propagation in the filled joints has been unclear. This study develops a novel dual-scale equivalent rock model to investigate the wave propagation in jointed rock masses. Firstly, two combination models at different scales were developed by using thin layers and contact interfaces to simulate filled joints and microdefects, respectively. Subsequently, a wave propagation equation was derived through a time-domain recursive method, and validated against the experimental data and the predictions of traditional models. Finally, a parametric analysis was conducted on the frequency response of wave propagation in jointed rock masses. The results show that this novel model can describe the wave dispersion and attenuation in dual-scale discontinuous rock masses, and its equation exhibits robustness. It is revealed that two independent mechanisms induce the wave dispersion in a single joint: multiple wave reflections inside the joint and the viscosity of the filling material. The effect of microdefects on wave attenuation mainly depends on propagation distance, while the influence of filled joints on wave propagation can be determined by the quality factor, thickness, effective wave velocity, and density of the filling. The wave velocity of the filling has a significantly higher influence on the transmission coefficient than the filling density. This challenges the conventional concept that the wave impedance of filling is a basic parameter for estimating the transmission coefficient. Highlights: A novel dual-scale equivalent model was proposed for wave propagation in jointed rock masses. The multiple reflection effects at rock joints were revealed to be the main cause of wave dispersion. Using wave impedance of joint filling to predict the transmission coefficient was found to be inaccurate. The frequency response difference in macroscopic and mesoscopic discontinuities of rock masses was revealed. [ABSTRACT FROM AUTHOR]

The Rb–Sr age of glauconite and the U–Pb LA-ICP-MS age of detrital zircons from sandstones of the Riphean Okos Formation and the Vendian Ust-Pinega Formation were determined in the Keltmen-1 parametric borehole, drilled in the Vychegda trough of the Mezen syneclise in the northern part of European Russia. The model Rb–Sr age of glauconite (870–820 Ma) and the U–Pb age of the youngest detrital zircon (1005 ± 14 Ma) limit the time of accumulation of the Okos Formation to the first half of the Late Riphean, which is in good agreement with the biostratigraphic data available. The U–Pb age of the youngest detrital zircon from the lower part of the Ust-Pinega Formation suggests that accumulation of Late Vendian sandstones into the Mezen Basin began about 575 Ma. Thus, the duration of the stratigraphic hiatus between the Riphean and Vendian is estimated to be about 250–300 Ma. In the Late Riphean and Late Vendian, the Mezen basin was filled with terrigenous material of Archean–Late Proterozoic age (from 3.25 to 1.02 Ga), the sources of which were rocks of the Baltic Shield. In the lower part of the Ust-Pinega Formation, a population of detrital zircon of Vendian age (730–575 Ma) was discovered, a possible source of which could have been rocks of the Proto-Ural–Timan Orogen. [ABSTRACT FROM AUTHOR]

The major purpose of this study is to analyze the resistance of honeycomb ceramic matrix composites to penetration and to explore the effect of the performance characteristics of the filler materials on this capability. We used alumina ceramics, polyurea, quartz sand powder, and boron carbide powder to manufacture composite materials, and conducted impact tests and numerical simulations on them. The simulation results of Abaqus were found to be very consistent with the test results. The results demonstrate that the polyurea coating and filler materials may effectively improve the anti-penetration penetration performance of the composites, and different filler materials have varying energy absorption effects. Extended research on composites was carried out utilizing experimentally validated numerical models with filler materials comprising silicon carbide, aluminum nitride, and silicon nitride. After a comparative analysis of the simulation results of different composites, compared to quartz sand composites, the energy absorption efficiency of boron carbide composites increased by 12.03 %, silicon carbide composites increased by 14.63 %, aluminum nitride composites increased by 15.16 %, and silicon nitride composites increased by 18.29 %. Among the relevant materials in this study, there exists an optimal value of the stress wave impedance difference between the matrix material and the filler material. Honeycomb ceramic matrix composites with an ideal combination of stress wave impedance differences can considerably increase the anti-penetration efficiency of the composites. [ABSTRACT FROM AUTHOR]

Backfilling mine goafs can significantly advance the mining industry; however, few researchers have used geopolymers reinforced with polypropylene fibers as filling materials. In this study, the flexural properties of fiber-reinforced green composite cementitious matrix–cemented tailings were examined, and the evolution mechanism of the internal structural properties of the prepared composite materials was determined. For this purpose, three-point bending tests, scanning electron microscopy, energy dispersive spectroscopy, and X-ray diffraction were performed on composite samples with different blending ratios, and discrete-element numerical simulations were conducted using PFC3D particle flow simulation software. The obtained results revealed that the flexural strength and fracture properties of the studied samples increased with increasing NaOH content, decreased with increasing water-to-solid ratio, and first increased and then decreased with increasing fiber content. At a fiber content of 0.6%, the reinforcement effect reached a local optimum. The higher the NaOH content, the more efficiently fly ash and slag formed polymerization products in an alkaline environment, which contained tailing sand aggregate particles, increasing the compactness of the composite structure. The fibers in the composite material were distributed both as a single inlay and as a three-dimensional network structure to form an effective wrapping and supporting system, which further improved the flexural performance of the sample. The PFC3D simulation data were consistent with the results of three-point bending tests, illustrating the sample degradation process. The findings of this work can provide a theoretical basis for the development of fiber-reinforced green sand filling materials for mine replenishment. [ABSTRACT FROM AUTHOR]

The effect of different filler types on the properties of asphalt mortar before and after water saturation was studied by laboratory tests. Under both dry and water-saturated circumstances, four alternative fillers, limestone powder, hydrated lime, PO42.5 cement, and brake pad powder, are used, evaluated, and compared. The study methodology included characterizing the micromorphology, while X-ray diffraction imaging analysis and scanning electron microscopy were used to determine the chemical composition of the asphalt mortar following water saturation. To quantify the effects of moisture on the bonding mechanisms, surface energy concepts were employed to compute the surface free energy parameters of the asphalt mortar made with different filler materials. Dynamic shear rheometry was employed in the investigation to describe the rheological characteristics of the asphalt mortar as a function of filler under different water saturation conditions. The bonding strength of the asphalt mortars with various fillers was then quantitatively measured using pullout tests to account for the coupling effects of moisture and temperature. The findings of the laboratory tests generally showed that the asphalt mortar's effectiveness declined following moisture conditioning and saturation in water. However, hydrated lime, brake pad powder, and cement showed promise in strengthening the bonding of fillers and asphalt, with hydrated lime being superior. Likewise, the asphalt mortar's ability to tolerate moisture and resist water damage was also generally improved by hydrated lime. [ABSTRACT FROM AUTHOR]

Thermal energy storage (TES) systems have been proven in their capacity as a crucial component of energy grids relying on renewable sources. An established sensible heat storage technology is a packed-bed TES, employing a granular filling material as a heat storage medium, which is subjected to repeated heating-cooling cycles. As a result of the recurring particle expansion and contraction, excessive stresses and strains can develop and cause material damage. This leads to the increasing need for reliable numerical tools in order to improve the TES design and increase their durability. For this purpose, we propose a continuous thermo-mechanical approach, within the framework of the theory of hypoplasticity, that can accurately predict the single as well as cyclic loading behavior of the filling material. This work focuses on the stress–strain relations and compaction mechanisms of the granular bed in contact with a storage wall with variable inclination and friction coefficient. Furthermore, the important aspect of the wall expansion under the temperature change is also taken into account as well as the specific case when the wall expands more than the granular material. By conducting comprehensive simulations, we demonstrate that our novel numerical model adheres to existing experimental investigations and mitigates shortcomings in the predictive capabilities of previous continuous approaches. [ABSTRACT FROM AUTHOR]

In this study, polyvinyl alcohol/Nafion nanofibrous composite membranes were produced to investigate their possible application as a polymer electrolyte membrane (PEM) in direct methanol fuel cells. Electrospinning method was used for nanofibrous membrane production, in which the mixture of polyvinyl alcohol (PVA) and Nafion solutions was directly electrospun. Produced nanofibers were subjected to physical stabilization, filler application, and sulfonating to produce composite nanofibrous membranes. PVA and Nafion polymers were used also as filler materials. The properties of resultant composite membranes were compared in terms of water swelling, weight loss in water and methanol solution, thermal stability, morphology, proton conductivity, and methanol permeability. Proton conductivity of the membranes depending on the humidity was also investigated. TGA analysis showed that the membranes had adequate thermal properties regardless of the filler material. The nanofibrous structure was shown to be preserved by scanning electron microscopy (SEM) after treatment with water and methanol solution. It was shown that PVA/Nafion nanofibers displayed proton conductivity after filling process. The use of PVA as a filler material led to higher proton conductivity at 100 RH%. It was reported that proton conductivity could only be obtained at higher relative humidity values (>80% RH). A lower methanol permeability of PVA‐filled membranes was reported. Highlights: PVA/Nafion nanofibrous membranes were produced by electrospinning.PVA and Nafion were also used as pore filling materials.PVA‐filled membranes had higher proton conductivity and lower methanol permeability.Proton conductivity could only be obtained at higher RH% values. [ABSTRACT FROM AUTHOR]

Coal spontaneous combustion (the term is hereafter abbreviated as CSC) is an important problem facing by China to achieve carbon peak and carbon neutrality. CSC affects the mining process of mining for a long time, not only causing a large amount of waste of coal resources, but also severely destroying the ecological environment. At present, filling & plugging materials (the term is hereafter abbreviated as F&P materials) is widely welcomed and developed rapidly because of its advantages of wide application, obvious performance and low price. Based on the research of the prevention and control of CSC and the materials applying for it, this paper creatively puts forward an application system of materials used for the prevention and control of CSC. The types of F&P materials are systematically summarized. According to the form of materials, the F&P materials are divided into slurry, colloid and foam. The performance and effect of three kinds of F&P materials are analyzed in detail. On this basis, the cost and environmental protection characteristics of F&P materials in China were compared and evaluated. Finally, this paper predicts the development of F&P materials. This paper provides an effective reference for Chinese coal mining enterprises to select suitable F&P materials, which is of great significance for the prevention and control of CSC and environmental protection. [ABSTRACT FROM AUTHOR]

In the contemporary era, the enhancement of wearable capacitive sensors is achieved through the utilization of polymeric micropillars as filler materials between electrode plates. To gain a deeper understanding of the dynamic response of the system, nonlinear coupled governing equations of a circular microplate motion resting on an array of polymeric micropillars have been derived. These equations are used to model the system's behavior. In addition, the squeezing motion of the micro-pillars is characterized using the incompressible Neo-Hookean model. Both static and dynamic responses, including transient and steady-state solutions, are investigated in detail by discretizing over spatial coordinates using a weak formulation approach. A frequency response analysis is conducted using a continuation-based method. This entails expanding the steady-state solution using a Fourier transform and employing the energy balance principle. The unknown coefficients of the expansion series are calculated using a gradient descent-based learning approach that is physically motivated. Furthermore, a dynamic step size strategy for frequency increments is employed to effectively follow the solution path. This strategy is implemented via the ARC length method. In this study, we examine the impact of varying PDMS (polydimethylsiloxane) hydrogel mechanical and geometrical configurations. It can be reasonably concluded that the mechanical properties of the pillars and the geometrical configuration of the circular plate and micropillars have a significant impact on the maximum tolerable pressure, fast transient response, and frequency response analysis. [ABSTRACT FROM AUTHOR]

To evaluate the effect of combining different bioactive root-end filling materials with composite bone graft (xenogeneic mixed with autogenous bone fragments) on the healing process of periapical tissues after endodontic micro-surgery procedure. In this triple-blinded clinical trial, 56 patients were divided into 2 main groups (28 each) according to the root-end filling material and 2 subgroups according to the presence or absence of the composite bone graft material. Group I: MTA root-end filling (n = 28) in which there are Sub-group A: without bone graft (n = 14) and Sub-group B: with composite bone graft (n = 14). Group II: TotalFill root-end filling (n = 28) in which there are Sub-group A: without bone graft (n = 14) and Sub-group B: with composite bone graft (n = 14). Healthy patients whose ages range from 20 to 50 years with small-to-medium size radiolucency in CBCT related to single-rooted maxillary teeth were included in this study. Patients were assigned a number starting from 1 to 56 and were randomly allocated to four test groups (2 main groups and 2 sub-groups) following simple randomization procedure guidelines described by IBM SPSS V23 (IBM USA) statistical analysis software. This trial was triple-blind where the patient, the outcome assessors, and the main operator were blinded to the applied intervention. Every patient was evaluated clinically and by CBCT at two main observation periods: presurgical and 12-month post-operative. They were also examined and evaluated clinically and radiographically through periapical x-rays after one week, three, and six months. Statistical analysis was performed with IBM SPSS Statistics for Windows Version 23.0. Armonk, NY: IBM Corp. Of the 56 patients enrolled in the study, 49 patients were available for the final analysis. All groups showed no statistically significant differences with regard to healing or success rates at the 12-month follow-up mark. No adverse effects were encountered. Results showed that high success rates were achieved using MTA and TotalFill in the healing of periapical lesions after endodontic surgery. The addition of bone graft in small-to-medium size lesions did not affect the success rate of endodontic surgeries. [ABSTRACT FROM AUTHOR]

Highlights The growing global demand for sustainable and environmentally friendly polymer materials is driving interest in cellulose‐based materials. In response to this need, lignocellulosic fillers (LF) were extracted from pruning waste of bing cherry tree (Prunus Avium L.) branches as an alternative source of filler materials. The extracted LF were characterized by Fourier transform infrared (FTIR) spectroscopy, X‐ray diffraction (XRD), thermogravimetric analysis (TGA) and scanning electron microscopy (SEM). Their chemical composition, density and particle size distribution (PSD) were also analyzed. In the second part of the study, biocomposites were prepared by incorporating fillers with particle sizes below 100 microns into an epoxy matrix at concentrations of 5%, 10% and 15% by weight. These biocomposites were then characterized by tensile test, three‐point bending test and SEM analyze to determine their mechanical and morphological properties. Among the biocomposites, the one with 5% wood filler showed the best properties with a tensile strength of 45 MPa, tensile modulus of 1883 MPa, flexural strength of 74 MPa and flexural modulus of 2559 MPa. The results demonstrate the effectiveness of lignocellulosic particles in improving polymer matrices and suggest their potential for use in non‐structural applications in the automotive and marine industries, such as interior panels. Cherry tree pruning waste has been characterized for the first time. The potential use of cherry tree pruning waste as a filler material in thermosets has been investigated for the first time. This study aims to contribute to the reduction of plastic consumption and the development of environmentally friendly products. [ABSTRACT FROM AUTHOR]

As it is known, Polytetrafluoroethylene (PTFE) is one of the most preferred polymeric materials for tribological applications. This study investigates the performance of PTFE and its composites under different tribological conditions. The effects of short glass fiber (GF), carbon particle (CP) and bronze particle (BP) reinforcement agents and their hybrid filling with molybdenum disulfide (MoS2) on sliding, erosive and abrasive wear were examined. Sliding tests were carried out with a ball‐on‐disc test apparatus, erosive wear tests were carried out with solid particle erosion and abrasive wear tests were carried out with a scratch test. It has been found that reinforcement agents improve sliding and abrasive wear resistance but worsen the erosion resistance. The hardness and contact angle of the samples were associated with their wear performances. Topographic and morphological analyzes of worn surfaces were performed using optical profilometer and scanning electron microscopy (SEM), respectively, and wear mechanisms were discussed. Highlights: Filling materials (glass fiber, carbon particle and bronze particle) increase the adhesion and abrasion resistance of PTFE, while decreasing its erosion resistance.The effect of hybrid addition of MoS2 solid lubricant on wear performances depends on the type of filler.There is a correlation between surface properties (hardness and contact angle) and wear performances.Optical profilometer and scanning electron microscopy were used to examine wear mechanisms. [ABSTRACT FROM AUTHOR]

Effective antibacterial therapy while accelerating the repair of bone defects is crucial for the treatment of osteomyelitis. Inspired by the protective mechanism of Andrias davidianus, we constructed an antibacterial hydrogel scaffold with excellent rigidity and long-term slow-release activity. While retaining the toughness of the skin secretion of Andrias davidianus (SSAD), the rigidity of the hydrogel material is increased by incorporating hydroxyapatite to meet the demands of bone-defect-filling materials. It also exerted antibacterial effects via the slow-release of vancomycin from local osteomyelitis lesions. Notably, the hydrogel can also carry a high stable recombinant miR-214-3p inhibitor (MSA-anti214). By the delivery of nano vector polyvinylamine, the long-term slow-release of MSA-anti214 is achieved to promote bone repair, making this composite hydrogel a potential SSAD-based osteomyelitis alleviator (SOA). In vitro and vivo results verified that the SOA effectively eliminated Staphylococcus aureus and repaired bone defects, ultimately mitigating the progression of osteomyelitis. This composite hydrogel extends the economic application prospects of A. davidianus and has provided new insights for the treatment of osteomyelitis. The study also explored new insights for the bone filling materials of bone defection and other skeletal system diseases. [ABSTRACT FROM AUTHOR]

Electrochemically exfoliated graphene (EEG) is compounded with copolyamide 6/66 (PA6/66) to investigate the influence of the carbonaceous filler material on the thermal, rheological, and mechanical properties of the composite. Toward that end, the environmentally friendly electrochemical exfoliation in aqueous solution is further developed to furnish graphene in large quantities. Separating the exfoliation process from the incorporation into the polymer matrix by wet phase inversion (WPI) allowed in‐depth characterization of the EEG by scanning electron microscopy (SEM), atomic force microscopy (AFM), and Raman spectroscopy. The crystallinity of copolyamide 6/66‐EEG is significantly changed, as revealed by differential scanning calorimetry (DSC). Likewise, the new composite materials exhibit different flow properties, as well as increased mechanical reinforcement with additive concentration. This is proven by dynamic shear rheology and three‐point stress tests compared to the neat polymer. [ABSTRACT FROM AUTHOR]

Concrete, a widely used construction material, is under scrutiny due to its environmental impact, primarily stemming from cement production. Researchers are exploring alternative materials and mix designs to mitigate these effects. Supplementary cementitious materials (SCMs) like Ground Granulated Blast Furnace Slag (GGBS) show promise, reducing carbon emissions and enhancing concrete properties. Additionally, the extraction of natural aggregates poses environmental and health risks, necessitating the use of sustainable waste materials. Various wastes, including GGBS and clastic sand, are being investigated for their suitability in concrete production. This study aims to evaluate the performance of concrete incorporating GGBS and clastic sand (CLS) as substitutes. Understanding their impact on concrete properties will aid in developing more sustainable construction practices, contributing to reduced carbon emissions. Test results show mechanical property improvements with increasing GGBS and CLS content up to an optimal point, beyond which further enhancement ceases, likely due to unreacted materials acting as fillers. Using the response surface method, compressive strength values closely match experimental observations with a confidence level exceeding 95%. This research underscores the potential of GGBS and CLS in enhancing concrete sustainability and performance, crucial for environmentally responsible construction practices. [ABSTRACT FROM AUTHOR]

Micro-cementing ungraded tailings and filling them into underground goafs is an effective method for mine tailings disposal. The paper introduces the filling system of Xiaomiaoling, including the filling process, the storage and conveying of cementitious materials, and the agitation system. This study investigates the sedimentation performance and compressive strength of the micro-cemented filling material using Xiaomiaoling-s ungraded tailings. The results indicate that the optimal slurry concentration for ungraded tailings is 10 %, with an optimal addition of 30 g/t of SNF625V flocculant and a slurry feed rate of 0. 5 t/(m²·h). As the slurry concentration increases, the strength of the filling body also increases; however, the strength decreases with a reduction in the cement-sand ratio. Additionally, the compressive strength of the filling body increases with the curing period. While meeting the mine-s filling process requirements and cost considerations, the recommended mix ratio for Xiaomiaoling-s micro-cemented filling with ungraded tailings is a cement-sand ratio of 1: 15 and a slurry concentration of 68%. [ABSTRACT FROM AUTHOR]

The utilization of biowaste fillers in the development of high-density polyurethane (PU) foams has gained significant attention due to environmental and economic benefits. This study investigates the mechanical properties of PU foams reinforced with biowaste fillers extracted from fish scales (FS) and fish scale-derived collagen (FSC). The fish scales and collagen were characterized for their composition and integrated into PU foams at various loadings. Mechanical properties such as tensile strength, hardness, and density were evaluated. ANOVA was used to analyze the mean values. Bonferroni tests were used to identify differences between the filler materials (α = 0.05). The tensile strength increases with an increase in filler content for both FS (59.48 Kpa) and FSC (65.43 Kpa). No differences were observed between FS and FSC in tensile strength. Significant differences were observed between the FS and FSC in both hardness and density (p < 0.001). The results demonstrated that both fillers enhanced the mechanical properties of PU foams, with collagen-reinforced foams showing superior performance. This suggests that collagen and fish scales can be effective biowaste fillers for developing environmentally friendly PU foams with enhanced mechanical properties. [ABSTRACT FROM AUTHOR]

Polarization, as a fundamental property of light, plays a key role in many phenomena of near‐field coupling, namely the coupling of source's evanescent waves into some guided modes. As a typical example of the polarization‐locked phenomenon in the near‐field coupling, the Janus dipole has the orientation of its near‐field coupling face intrinsically determined by the polarization state of linearly‐polarized surface waves, specifically whether they are transverse‐magnetic (TM) or transverse‐electric (TE) surface waves. Here, a mechanism to achieve the directional near‐field coupling of Janus dipoles beyond polarization locking by leveraging hybrid TM‐TE surface waves is presented. These hybrid surface waves, as eigenmodes with both TM and TE wave components, can be supported by optical interfaces between different filling materials inside a parallel‐plate waveguide. Under the excitation of hybrid surface waves, it is found that the coupling and non‐coupling face of a Janus dipole may be switched, if the Janus dipole itself rotates in a plane parallel to the designed optical interface between different filling materials, without resorting to the change of surface‐wave polarization. The underlying mechanism is due to the capability of hybrid surface waves to extract both the source's TM and TE evanescent waves, which offers an alternative paradigm to regulate the interference in the near‐field coupling. [ABSTRACT FROM AUTHOR]

In this paper, the mechanical properties and internal stress condition of the reinforcing bar sleeve connectors with ferro-tailed mineral sand cementitious grout as filler material were analyzed as research objects. Firstly, an experimental study was carried out on the reinforcing bar sleeve connectors of iron tailing sand grout with a 40% substitution rate of mechanism sand to analyze the mechanical properties of different grout types, age, and reinforcement diameters under unidirectional tensile, high stress, and large deformation of repeated tensile and compressive stresses. Next, five groups of sleeve joints with different anchorage lengths were set up for unidirectional tensile tests. The results show that, with the decrease of the diameter of the reinforcement, the grip force and bond strength of the iron tailing sand grout on the internal reinforcement gradually increase. Under conditions of large deformation and high stress due to repeated tensile loading, the residual deformation and total elongation of iron tailing sand grout sleeve joints are satisfactory. Additionally, the restraining anchorage effect of iron tailing sand grout in the end section is small. The utilization rate and integrity of iron tailing sand grout in the initial anchorage section are better. [ABSTRACT FROM AUTHOR]

In the present work, the Q345B low-alloy steel with different contents and ER309L stainless steel were melted together to obtain new alloys. The aim was to design the composition of weld metal (Q345B low-alloy steel as the base material and ER309L welding wire as the filler material) and improve the corrosion resistance of the weld metal. During the welding process, the composition of the weld metal was controlled to match the new alloys by changing the welding heat input. A relationship curve between fusion ration and welding heat input was obtained. The research focused on analyzing the effect of mixed-smelting ratio between Q345B and ER309L and welding heat input on the microscopic structure and corrosion performance of the prepared samples. The results show that the melted alloys containing 20% to 30% Q345B consist of a ferrite (δ) phase and austenite (A) phase, the samples containing 45% to 50% Q345B consist of a martensite (M) phase and austenite (A) phase, and the sample containing 40% Q345B consists of a martensite (M) phase, ferrite (δ) phase, and austenite (A) phase. As the mixed-smelting ratio of Q345B/ER309L increased, the corrosion resistance of samples decreased gradually. For the weld metal, the fusion ration between Q345B base material and ER309L welding wire increases with the welding heat input. When the heat input changed from 0.645 kJ/mm to 2.860 kJ/mm, the composition of the weld metal was consistent with the melted alloys containing 20–45% Q345B. The microstructure and corrosion resistance of the weld metal could be designed by the melting means, which has important guiding significance for engineering applications. [ABSTRACT FROM AUTHOR]

AlB2${\rm AlB}_{2}$‐type TaB2${\rm TaB}_{2}$ is one of the transition‐metal diborides, a class of refractory ceramics, that has increasingly received attention due particularly to their potential for hard‐coating applications. In this work, the first‐principles calculations are performed, in combination with the cluster‐expansion method, to investigate the effect of mixing AlB2${\rm AlB}_{2}$ with TaB2${\rm TaB}_{2}$ on the thermodynamic stability, structural parameters, electronic density of states, and mechanical behavior of the resulting (Ta,Al)B2${\rm B}_{2}$ solid solutions. It is found that the solid solutions display the chemical ordering of Ta and Al atoms both residing on the metal sublattice of the material, together with the preference for partial substitution of vacancies for Al atoms. This results in the formation of Al‐deficient (Ta,Al)B2${\rm B}_{2}$ with the chemical composition Ta0.6Al0.3B2${\rm Ta}_{0.6} {\rm Al}_{0.3} {\rm B}_{2}$, predicted to be thermodynamically stable even at absolute zero in the ternary Ta−Al−B system. It is further found that such formation of Al vacancies in (Ta,Al)B2${\rm B}_{2}$ not only enhances the stability of the solutions but also improves their elastic properties and hardness, both of which could be attributed to the effect of electronic band filling. This investigation indeed sheds light on the interplay between the mixing of Ta and Al atoms and the presence of Al vacancies on the alloying and mechanical behaviors of (Ta,Al)B2${\rm B}_{2}$, and it thus offers valuable insights for further research and development of these ceramics. [ABSTRACT FROM AUTHOR]

Recently, bio-composites have attracted much attention due to their potential applications in various industries. The most notable benefits are the product's low cost, biodegradability, lightweight, availability, and ability to solve environmental issues. The present research utilizes ash gourd (Benincasa hispida) peel, a food waste, as a filler material to produce epoxy (EP) composites. The effect of ash gourd peel particle percentage (ranging from 0 to 25 wt.%) was studied on the developed composites' mechanical and thermal properties and water absorption behavior. The maximum tensile strength, flexural strength, and shore D hardness were 47.52 MPa, 2409.17 MPa, and 79.6respectively, when the ash gourd peel was 5% by weight in the composite. It was observed that the mechanical characteristics of manufactured bio-composites are negatively affected by the high concentration of ash gourd peel particles in the epoxy matrix. Also, increasing ash gourd peel particle fraction increases the water absorption of composites when immersed in distilled, sea, and tap water. The composite with 5% filler by weight absorbs water at a minimal rate when immersed in seawater. Thermogravimetric analysis was conducted to investigate the newly developed composite's thermal behavior. In addition, a morphological examination of the fractured surfaces was carried out with assistance from a scanning electron microscope. The work presents ash gourd peel particles as the potential alternative to be used as filler in composites. [ABSTRACT FROM AUTHOR]

Background: Nonsurgical cosmetic procedures, particularly the use of hyaluronic acid (HA)‐based soft tissue fillers, are becoming increasingly popular. This trend has catalyzed the development of a plethora of HA‐based products differing in product characteristics, thereby catering to an ever‐widening spectrum of aesthetic applications. However, complications rise concomitant with the increasing number of procedures. Among the strategies to manage such adverse events is the enzymatic breakdown with hyaluronidase. Objective: To analyze the response of different HA‐based soft tissue filler materials to hyaluronidase injections. Methods: A total of 11 different HA‐based soft tissue fillers were evaluated using noninvasive ultrasound imaging to assess their behavior in response to hyaluronidase injections. The HA‐based soft tissue fillers were categorized according to their product characteristics into a structuring, volumizing, and lip volumizing group. Standardized injections of 0.2 cc were performed in chicken breast to simulate human tissue. Ultrasound measurements of width, height, and calculated volume were performed immediately after filler injection, 1 h and 24 h following hyaluronidase injection. Results: Regardless of the soft tissue filler analyzed, the most significant volume reduction occurred within the first h after applying hyaluronidase, with a 64.1% decrease from the initial volume. After 24 h, the total volume reduction reached 81.7%. No statistically significant differences were found when comparing the three groups at each follow‐up time period, except for the height measurement after 1 h. While width was statistically significant in all groups between the investigated follow‐up groups, the volume reduction was only statistically significant in the groups with the highest and second highest G' values (i.e., Group 1—structuring, Group 2—volumizing). Conclusion: The effectiveness of hyaluronidase in dissolving HA‐based fillers is initially independent of product characteristics of HA‐based fillers such as G‐prime, with increased efficacy in fillers with higher G‐prime values, as evidenced by significant volume reductions in such groups. [ABSTRACT FROM AUTHOR]

Hexagonal boron nitride (HBN), an artificial material with unique properties, is used in many industries. This article focuses on the extent to which hexagonal boron nitride and silica nanoparticles (MSN) affect the physicochemical and mechanical properties and antimicrobial activity of prepared dental composites. In this study, HBN, and MSN were used as additives in dental composites. 5% and 10% by weight of HBN are added to the structure of the composite materials. FTIR analysis were performed to determine the components of the produced boron nitride powders, hexagonal boron nitride-containing composites, and filling material applications. The structural and microstructural properties of dental composites have been extensively characterized using X-ray diffractometry (XRD). Surface morphology and distributions of nano boron nitride were determined by scanning electron microscopy (SEM)-EDS. In addition, the solubility of dental composites in water and their stability in water and chemical solution (Fenton) were determined by three repetitive experiments. Finally, the antimicrobial activity of dental composites was detected by using Minimum Inhibitory Concentration (MIC) measurement, as well as Minimum Fungicidal Concentration (MFC) method against yeast strain Saccharomyces cerevisiae, and Minimum Bactericidal Concentration (MBC) method against bacteria strains, Staphylococcus aureus and Escherichia coli. Since the HMP series have better antimicrobial activity than the HP series, they are more suitable for preventing dental caries and for long-term use of dental composites. In addition, when HMP and HP series added to the composite are compared, HMP-containing dental composites have better physicochemical and mechanical properties and therefore have a high potential for commercialization. [ABSTRACT FROM AUTHOR]

To evaluate the impact on the quality of filling with of low-fusion and conventional gutta-percha cones. Thirty-six maxillary canines were prepared and divided into three groups: I—conventional cone with Downpack at 200 °C at 4 mm from the WL; II—low-fusion cone with Downpack at 100 °C up to 4 mm from the WL; III—low-fusion cone with Downpack at 100 °C up to 7 mm from the WL. Temperature variations were measured in thirds on the external surface of the root. The bond strength was evaluated using the push-out test. The adhesive interface was analyzed by scanning electron microscopy. The bond strength and the temperature variation data were analyzed using analysis of variance and the failure type using the chi-square test. The low-fusion cone group with 7 mm Downpack showed higher bond strength (4.2 ± 2.7) compared with conventional cones (2.8 ± 1.6) and low-fusion cones with 4 mm Downpack (2.9 ± 1.6) (p < 0.05), with occurrence of a higher number of adhesive failures to the filling material and mixed failures. Relative to temperature variation, there was less temperature change in the apical third, in the low-fusion cone with Downpack 7 mm (1.0 ± 1.0) (p < 0.05). The use of low-fusion cones allowed the continuous wave condensation technique to be performed at a lower depth of Downpack at 100 °C at 7 mm, with less heating in the apical third, without compromising the quality of filling. Using gutta-percha cones with low fusion, which permits a lower condensation temperature and reduced Downpack depth, maintains the quality of filling, in order to minimize possible damage to the periapical tissues. [ABSTRACT FROM AUTHOR]

The incorporation of filler materials to enhance the properties of fibre-reinforced plastics is a prevalent practise in materials science. Calcium carbonate is a commonly used inorganic filler in composite fabrication. Eggshell, a rich source of calcium carbonate, offers an organic alternative to conventional inorganic fillers. This study investigates the efficacy of different types of eggshells as filler materials. Three variants, viz., unhatched raw eggshell, unhatched boiled eggshell, and post-hatched eggshell, were used to fabricate composite variants, which were then subjected to mechanical characterization and compared with unfilled composites. The results indicated that composites filled with unhatched eggshells outperformed those with post-hatched eggshells. Tensile testing revealed a significant enhancement in the tensile properties of all eggshell-filled composites in comparison to the unfilled ones. The composite variant filled with unhatched raw eggshell filler showcased the utmost tensile modulus and strength, with a notable 36% improvement in comparison with the unfilled variant. Similarly, flexural tests demonstrated a 53% increase in flexural strength for unhatched raw eggshell-filled composites over unfilled composites. SEM imaging confirmed these findings by showing crack arrests, deviations, particle distribution, and strong interfacial bonding in the eggshell-filled composites. [ABSTRACT FROM AUTHOR]

Hydrogels have garnered significant interest in the biomedical field owing to their tissue-like properties and capability to incorporate various fillers. Among these, injectable hydrogels have been highlighted for their unique advantages, especially their minimally invasive administration mode for implantable use. These injectable hydrogels can be utilized in their pristine forms or as composites by integrating them with therapeutic filler materials. Given their primary application in implantable platforms, enzymatically crosslinked injectable hydrogels have been actively explored due to their excellent biocompatibility and easily controllable mechanical properties for the desired use. This review introduces the crosslinking mechanisms of such hydrogels, focusing on those mediated by horseradish peroxidase (HRP), transglutaminase (TG), and tyrosinase. Furthermore, several parameters and their relationships with the intrinsic properties of hydrogels are investigated. Subsequently, the representative biomedical applications of enzymatically crosslinked-injectable hydrogels are presented, including those for wound healing, preventing post-operative adhesion (POA), and hemostasis. Furthermore, hydrogel composites containing filler materials, such as therapeutic cells, proteins, and drugs, are analyzed. In conclusion, we examine the scientific challenges and directions for future developments in the field of enzymatically crosslinked-injectable hydrogels, focusing on material selection, intrinsic properties, and filler integration. [ABSTRACT FROM AUTHOR]