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Mn3Sn is an anomalous Hall effect (AHE) antiferromagnet that exhibits the hysteretic AHE in antiferromagnetic (AFM) phase at room temperature. We report that whisker Mn3Sn crystals grown by the flux method exhibit a non-hysteretic AHE at mid-to-low temperatures when the whisker Mn3Sn is surrounded by a thin layer of ferromagnetic Mn2−xSn. These crystals exhibit a hysteretic AHE above 275 K due to the spin alignment of the inverse triangular lattice, which is similar to other crystals. However, upon cooling the crystal, it exhibits a non-hysteretic AHE with a spiral AFM spin structure at 100–200 K. We concluded that the non-hysteretic AHE is induced at the interface of Mn2−xSn/Mn3Sn. We believe that the scalar-spin chirality in the spiral AFM phase of Mn3Sn, modulated by Mn2−xSn through the magnetic proximity effect, produces the AHE. This discovery opens a new avenue for tailoring the AHE by magnetic layers. [ABSTRACT FROM AUTHOR]

Cost-effective decarbonization and structural strengthening of carbon-containing refractory materials are crucial for the development of low-carbon steel (LCS) and ultra-low-carbon steel (ULCS) technologies. In this study, a carbonaceous-ceramic reinforcement assembly structure composed of multilayer graphenes and silicon carbide whiskers/particles (MLGs-SiC w /SiC p) has been successfully designed and fabricated. By employing three-roll milling (TRM) for low-cost exfoliation of expanded graphite (EG) into MLGs in a phenolic resin (PF) medium, we optimized the exfoliation cycles to fine-tune the morphology of MLGs. Subsequently, the catalytical solid-state conversion of PF/MLGs reacting with Si into SiC w /SiC p at 1400 °C, under varying C/Si molar ratios and catalyst contents, not only retained the structural integrity of MLGs but also embedded them within a novel SiC w /SiC p composite matrix. Our research elucidates the catalytic conversion mechanism, underscoring the significant role of nickel catalysts in promoting efficient SiC conversion. This work offers a promising pathway for developing high-performance, economical, low-carbon refractories. [ABSTRACT FROM AUTHOR]

Zirconium boride (ZrB2) whiskers hold significant potential for toughening ultra‐high temperature ceramics (UHTCs). Yet, their fabrication remains challenging due to limited knowledge of the microstructure evolution. Herein, high‐purity ZrB2 whiskers were successfully prepared by electrospinning combined with carbothermal reduction. Specifically, a precursor solution containing Zr–O–C–B networks stabilized through hydrogen bonds with polyvinyl pyrrolidone was synthesized as a spinnable ZrB2 precursor. High‐purity ZrB2 whiskers with a diameter of ca. 200 nm and a length of 5–10 µm were obtained by precise heat treatment of ZrB2 precursor fibers. In this process, ZrO2 grains formed initially and transformed into ZrB2 grains through carbothermal reduction, which further converted into ZrB2 whiskers through a solid‐liquid‐solid mechanism. To testify to the toughening effect for UHTCs, the ZrB2 whiskers were added into ZrB2 powders and followed by sintering. This strategic addition of 5 wt% ZrB2 whiskers led to a 19% enhancement in the fracture toughness of ZrB2 bulk. This study illuminated the preparation strategy and formation mechanism for ZrB2 whiskers and their application for toughening UHTCs. [ABSTRACT FROM AUTHOR]

Recent works exploiting photonic valley Hall effect show that large-area topological states can be realized by inserting gapless photonic crystal structures into topological interfaces, thus effectively introducing mode width degree of freedom. However, the previously reported works focus on gapless edge states. It is rare to investigate gapped edge states, especially large-area gapped edge states. In this paper, large-area gapped edge states in a valley photonic crystal heterostructure are achieved and experimentally proved. Compared with large-area gapless topological states, the present gapped edge states are more localized, which provides a more effective way to manipulate electromagnetic waves. We implement a topological energy concentrator and topological resonator cavity based on the large-area topological transmission with the gapped edge states. It is expected that our results broaden photonic systems, which can be used in topological lasing, field enhancement, and high-capacity energy transport. [ABSTRACT FROM AUTHOR]

Near‐infrared‐II (NIR‐II) phosphors are extensively used as NIR phosphor‐converted light‐emitting diodes across various applications. Nonetheless, their application in fiber communication remains underexplored. Furthermore, efficiency challenges persist in developing broadband NIR crystal fiber amplifiers. A series of the Y3−yAl5−xO12:xCr,yCa2+ phosphors with boosted Cr4+ concentration via calcium charge compensation is synthesized, and the optimized sample is fabricated to crystal fibers to reveal the application of the NIR‐II phosphors to fiber communication. The fabricated Cr4+‐doped crystal fiber, exhibiting broadband Cr4+ emission within 1100–1600 nm, effectively covers the high‐transmission loss region caused by water absorption in the telecommunication band. Comprehensive characterization and analyses of the Cr4+ are discussed. Y2.84Al4.9O12:0.1Cr,0.16Ca2+ crystal fiber, fabricated through phosphor synthesis, pellets' production, and the laser‐heated pedestal growth method, exhibits superior photoluminescence compared to the commercial Cr4+‐doped Y3Al5O12 crystal fiber. Here the potential of NIR‐II phosphors is highlighted in enhancing fiber communication and valuable insights for their future application are provided. [ABSTRACT FROM AUTHOR]

The advent of flexible electronics has prompted the development of functional fibers with superior mechanical and electrical properties. MXenes, a novel family of 2D functional materials, have a variety of potential applications in flexible electronics. Herein, wet‐spinning is employed to continuously assemble Ti3C2Tx MXene liquid crystals into macroscopic fibers. Meanwhile, Zn2+ is introduced into the fiber to eliminate the electrostatic repulsion between the MXene nanosheets and enhance interlayer interactions and sheet alignment. The as‐obtained MXene fibers have strong mechanical strength (150.7 MPa), high electrical conductivity (3637.9 S cm−1), and good flexibility that facilitates weaving and knotting, making them suitable for fabric‐like flexible devices. The sound pressure sensors are woven from MXene fibers, which feature quick response time (286 ms) and recovery time (642 ms), ultra‐high sensitivity (280.2 kPa−1), and a low detection limit (0.1 Pa). Sound detection and recording are achieved using this sensor. MXene fibers as wearable thermal management devices are also demonstrated, exhibiting fast Joule thermal responses and good cycling stability. [ABSTRACT FROM AUTHOR]

Highlights Wind turbines are subjected to extreme weather and load conditions; hence, high strength and impact resistance are required. Furthermore, wind turbine blades can be subjected to impact loads such as bird strikes, resulting in the formation of microcracks. Self‐healing capsules can be used to mend turbine blades for microscale damage. The incorporation of self‐healing capsules may cause a decrease in the mechanical characteristics of the composites prior to impact resistance, which can be compensated for with efficient fillers such as silicon carbide whiskers (SiCw). Thus, a novel hybrid composite structure is examined with the advantage of using a self‐healing mechanism and SiCw reinforcement. Tensile, tribological, and Charpy impact tests were performed to characterize the mechanical and tribological properties, which were supported with microscopic observations. Multiple experimental characterizations were performed to investigate the impact, and the ultimate tensile strength (UTS) and energy absorption capacity of the structure were shown to increase by 32% and 45%, respectively, with the addition of SiCw. The presence of self‐healing agents provides a 5% rise in UTS after enough time for healing following the collision. The structure's tribological performance is improved by 10% in wear resistance and 20% in friction coefficient. Hybrid laminated composite structure with silicon carbide whisker and self‐healing capsules. Tensile and Charpy impact tests conducted with microscopic observations Increased ultimate tensile strength and energy absorption capacity by 32% and 45%. Tribological improvement by 10% in wear resistance and 20% in friction coefficient. [ABSTRACT FROM AUTHOR]

In this paper, highly electrically and thermally conductive copper powders (Cu) and electrically insulative yet thermally conductive silicon carbide whiskers (SiCw) were selected as functional fillers and high‐density polyethylene (HDPE) was used as the matrix to prepare thermal conductive composites. By controlling the amount of Cu at 30 vol% which is below percolation threshold, the volume resistivity of the composites is maintained above 1014 Ω cm. The results showed that SiCws entered the area which was not occupied by Cu particles and they played a bridging effect among Cu particles, thereby promoting the formation of intact thermal conductive pathways that contributed to improving the thermal conductivity of corresponding composites. The combination of SiCw:Cu = 3:1 at a filler content of 30 vol% resulted in a thermal conductivity as high as 1.921 W/mK, which is 380% higher than pure HDPE. [ABSTRACT FROM AUTHOR]

AbstractSelf-sustained movement has the ability to absorb energy from the external environment to maintain its own movement. In the present work, a self-sustained chaotic simple pendulum system featuring an electrothermal responsive liquid crystal elastomers fiber and a mass ball is proposed and examined. The power-on state is achieved in the system through the infusion of liquid metal into this fiber. Which enables the fiber to shrink, feeding energy into the system to compensate for the energy dissipation resulting from damping, thus allowing the system to maintain its self-sustained movement. On the basis of the existing dynamic liquid crystal elastomer model, the dynamic governing equations are established, and the movement behavior of the system under electrothermal stimulation is theoretically explored. Numerical findings suggest that the simple pendulum system presents three different movement patterns, namely stationary pattern, self-sustained oscillatory pattern, and self-sustained chaotic pattern. Moreover, five system parameters of elastic coefficient, viscosity coefficient, gravitational acceleration, shrinkage coefficient and electrothermal strength are examined. The present work can contribute to a better understanding of self-sustained chaotic systems driven by electrothermal responsive materials and offer guidance for further exploration of applications such as chaos machine, and mind-brain chaos analysis. [ABSTRACT FROM AUTHOR]

ZrB 2 –SiC–Si 3 N 4w ceramics (ZSN w) were prepared via the hot-pressing sintering method. The bending strength and fracture toughness of ZSN w at room temperature reached to 520 ± 24 MPa and 5.2 ± 0.16 MPa m1/2, respectively. The enhancement in mechanical properties is attributed to the grain refinement and attenuation of grain boundary induced by the homogeneous distribution of Si 3 N 4 whiskers. The oxidation resistance of ZSN w were conducted at 1500 °C in an air atmosphere. Remarkably, after 10 h of oxidation, ZSN w remained excellent strength and toughness reaching at 589 ± 26 MPa and 4.8 ± 0.12 MPa m1/2, respectively. This oxidation resistance of ZSN w was mainly attributed to the gain refinement induced by Si 3 N 4 whiskers, which effectively reduced the voids within the ceramic matrix. Therefore, this process promoted the densification and homogenization of the SiO 2 protective barriers, accompanied with hindering the inward permeation of oxygen and the outward release of oxides. [ABSTRACT FROM AUTHOR]

High-purity SiC ceramic membrane has gained tremendous attention in the treatment of various corrosive wastewaters. Additive manufacturing technique makes it possible to fabricate high-purity SiC ceramic membrane with complex configurations. Here, we proposed a route for the preparation of high-purity SiC ceramic membrane support using digital light processing and SiC whisker reinforcement. With the increase of whisker content, the viscosity of SiC w /SiC photosensitive slurry increased due to the formation of whiskers agglomerations; the average pore size shifted from 3.15 μm to 1.35 μm with the occupation of large pores by SiC whiskers. In addition, the compressive strength of the ceramic support increased from 10.7 MPa to 16.7 MPa because of the decline in pore size and the toughening effects by SiC whiskers. So, the introduced SiC whiskers enhanced the pore connectivity and mechanical strength of the porous ceramics. This work provides a feasible path to manufacture high-purity SiC ceramic membrane support with complex configuration, high pore-connectivity and excellent mechanical properties. [ABSTRACT FROM AUTHOR]

Multiscale fiber hybridization is an essential method for enhancing and toughening cement-based materials. In this study, the influence of the content of calcium carbonate whiskers (CW) and polyvinyl alcohol (PVA) fibers on the flexural properties of cementitious composites containing 1.5% by volume steel fibers was investigated by using the hybridization of CW, PVA fibers, and steel fibers based on the four-point bending notched test. The distribution characteristics of PVA fibers and steel fibers in multiscale hybrid fiber-reinforced cementitious composites (MFRC) were analyzed and evaluated using backscattered electron imaging (BSE). The results demonstrated that the addition of an appropriate amount of CW and PVA fibers effectively improved the flexural performance of steel fiber–reinforced cementitious composites and promoted a more uniform distribution of steel fibers within the matrix. The MFRC with 1% by volume CW, 0.3% by volume PVA fiber, and 1.5% by volume steel fiber (C1P03S15) exhibited the highest flexural toughness coefficient (σb) and fiber dispersion coefficient (γ), which increased by 46.2% and 81.4%, respectively, compared to the control group without CW. Furthermore, a strong correlation between σb and γ was observed through fitting, indicating the potential for guiding practical engineering applications. [ABSTRACT FROM AUTHOR]

Implant materials with micro/nanostructures bear a closer resemblance with the features of natural bone, which influences the wettability, bone differentiation, and vascularization of materials. However, it is still technically challenging to design the inner wall and surface micro/nanostructures on macroporous bioceramics due to their brittleness. In this work, micro/nanostructured composites with Si3N4 whiskers as a framework, and the (inner) surface covered with SiC nanowires were prepared, denoted as SiC‐nw@Si3N4‐w bioceramics. The synthesis, adopting the green chemistry concept, was utilized from environmental products (carbon evaporated in the furnace at high temperature) and reaction impurities (carbon obtained by polymer pyrolysis and silicon obtained by Si3N4 decomposition) to synthesize SiC nanowires via a vapor‐solid growth mechanism. The prepared SiC‐nw@Si3N4‐w bioceramics have potential applications in bone repair due to their cell adhesion and proliferation. [ABSTRACT FROM AUTHOR]

Panchatikta is an Ayurvedic multiherbal combination containing five bitter‐tasting drugs—Azadirachta indica, Tinospora cordifolia, Justicia adhatoda, Solanum virginianum, and Trichosanthes dioica. The objective of this study is to develop standards for Panchatikta ingredients using pharmacognostic parameters and to analyze the chemical composition. The plant materials were collected from different natural habitats, authenticated, dried, ground, and the combination was prepared by mixing the ingredients in equal amounts followed by macroscopic, organoleptic, microscopic, histochemical, and physicochemical characterization according to the standard protocol of the Ayurvedic Pharmacopoeia of India. Special morphological characteristics of the A. indica (stem bark), T. cordifolia (stem), J. adhatoda (roots), S. virginainum (roots), and T. dioica (aerial parts) were identified. The anatomical structure of each drug was observed, and microscopic markers were developed for identification. Histochemical deposits such as starch, oil, lignin, and tannin were located in each plant material. Powder characters such as fibers from phloem with pointed ends and narrow lumen, parenchyma cells containing starch grains, crystal fibers, fragments of bordered pitted vessels, fragments of pitted vessels, cells containing black powdery masses, and epidermal cells from leaves in surface view with an anomocytic stomata were identified as the key features for the Panchatikta combination. The organoleptic characterization of component drugs and combinations was performed. The physicochemical evaluation of parameters such as ash content (5.53 ± 0.29), water‐insoluble ash (4.57 ± 0.32), acid‐insoluble ash (1.55 ± 0.31), alcohol‐soluble extract (5.9 ± 1.21), water‐soluble extract (9.19 ± 0.21), fiber content (33.27 ± 1.37), total sugar (1.83 ± 0.65), and reducing sugar (1.73 ± 0.40) were evaluated for the Panchatikta combination. Preliminary phytochemical tests were carried out to verify the presence of alkaloids, flavonoids, saponins, tannins, phenols, glycosides, and steroids. The HPTLC profile comparison of ethanolic, hydroalcoholic, and aqueous extracts of Panchatikta and single drugs showed some type of synergy and antagonistic activities among the chemical principles present. Marker‐based screening of azadirachtin, betulinic acid, and lupeol was done in Panchatikta ethanol using HPTLC. As Panchatikta is prescribed for various life‐threatening diseases including cancer, the standards developed here ensure the authenticity of the ingredients, which in turn ensures the quality of the prepared medicines. [ABSTRACT FROM AUTHOR]

The study investigated the phase transformation and microstructural comparison of two types of continuous alumina fibers with varying silica contents. These fibers were subjected to heat treatment at temperatures of 1100, 1200, 1300, and 1400 °C in air. By comparing the experimental results of the two different fibers, relevant influencing mechanisms were derived. The appearance of mullite phase in the fibers occurred when the heat treatment temperature reached 1200 °C. Variations in silicon content led to inconsistent pinning effects, resulting in differences in the occurrence of irregular structures on the surface of the two types of fibers. Following heat treatment at 1300 °C, the fibers exhibited scale-like and mosaic-like structures, accompanied by phase aggregation. Subsequent heat treatment at 1400 °C resulted in the fibers displaying layered structures composed of α-Al 2 O 3 phase and undergoing significant changes in microstructure. Notably, the two types of fibers exhibited a significant difference in the presence or absence of a glass phase, and the addition of silicon oxide to a certain extent was found to inhibit the crystal transformation of Al 2 O 3. Additionally, the experimental results were analyzed in terms of influencing mechanisms based on theories such as activation energy barriers and total free energy. [ABSTRACT FROM AUTHOR]

In this paper, the heat treatment of alumina fiber was studied. The infiltration agent on the fiber surface was removed after heat treatment at 450 °C for 6 h. TG-DSC, scanning electron microscope, x-ray diffraction, Fourier infrared spectrometer, energy dispersive spectrometer, and patterning were used to analyze the thermal weight loss, fiber surface morphology, crystal structure, and composition of alumina fibers. The results show that the aluminum oxide fiber has excellent temperature resistance and does not undergo crystal phase transformation during thermal weight loss. After heat treatment, the fiber surface infiltration agent ablates and dissolves from the fiber surface, and the internal crystal structure of the fiber remains stable. The tensile testing machine was utilized to test the breaking strength of alumina fiber. The fiber still maintained high strength after heat treatment, and the retention rate of breaking strength was greater than 74%. ZC-90G high insulation resistance measuring instrument and WDY-Ⅱ automatic voltage tester were utilized to analyze the insulation resistivity and breakdown strength of alumina fiber before and after heat treatment. The results show that heat treatment can effectively improve the insulation performance and breakdown strength of alumina fiber. [ABSTRACT FROM AUTHOR]

AbstractThe aim of this study is to characterize the Cattaneo-Christov heat flux in magnetohydrodynamics (MHD) radiative flow of Williamson nanofluid through a stretched sheet when confronted with heat source, Arrhenius activation energy and motile microorganisms. Also, the Darcy-Forchheimer model is a widely used and precise technique for modeling fluid dynamics in porous medium. The controlling partial differential equations (PDE) are minimized to ordinary differential equations (ODE) using suitable similarities. The final outcomes were computed numerically using the BVP4C MATLAB interface. The graphical portrayal serves to comprehensively show and build upon the effect of several aspects. The results reveal the increased velocity distribution with the intensifying values of magnetic field, porosity, suction, and Forchheimer number. The thermal gradient is enhanced with the increase in heat source, and radiation, while it diminishes with the augmentation of the thermal relaxation parameter. Furthermore, the concentration maximizes when the activation energy is large. This research shows a favorable link between Peclet quantity and motile microbe density. Additionally, this work numerically analyses and tabulates important engineering metrics such as skin friction, Nusselt number, Sherwood number, and motile density number. The present study has huge interest due to its applications such as food processing, crystal formation in rocks, microelectronic semiconductors, crystal fiber, electronic power plants, and many more. [ABSTRACT FROM AUTHOR]

This study investigates the mechanism and effects of incorporating different ZrO2 nano-particles into SAC0307 solder alloys. ZrO2 nano-powder and nano-fibers in 0.25–0.5 wt% were added to the SAC0307 alloy to prepare composite solder joints by surface mount technology. The solder joints were shear tested before and after a 4000 h long 85 °C/85% RH corrosive reliability test. The incorporation of ZrO2 nano-particles enhanced the initial shear force of the solder joint, but they decreased the corrosion resistance in the case of 0.5 wt%. SEM, EDS, and FIB analysis revealed intensive growth of SnO2 on the solder joint surfaces, leading to the formation of Sn whiskers. Density functional theory (DFT) simulations showed that, despite Sn being able to bond to the surface of ZrO2, the binding energy was weak, and the whole system was therefore unstable. It was also found that ZrO2 nano-particles refined the microstructure of the solder joints. Decreased β-Sn grain size and more dispersed intermetallic compounds were observed. The microstructural refinement caused mechanical improvement of the ZrO2 composite solder joints by dispersion strengthening but could also decrease their corrosion resistance. While ZrO2 nano-particles improved the solder joint mechanical properties, their use is recommended only in non-corrosive environments, such as microelectronics for space applications. [ABSTRACT FROM AUTHOR]

The design and engineering of liquid crystal elastomers (LCE) composites for enhanced multifunctionality and responsiveness is highly desired. Here, a hollow LCE (h‐LCE) fiber fabricated via coaxial spinning, enabling the straightforward yet effective creation of functional LCE composites, is reported. Inspired by the fiber‐tubule architecture in skeletal muscles, the hollow fiber features an LCE outer shell for programmable actuation and an inner channel allowing for the integration of a variety of functional media. Thus, the h‐LCE fiber can serve as a versatile platform for multifunctionalities in LCE composites. With this unique design strategy, h‐LCE fibers are fabricated with lengths exceeding 3 meters in the lab with outer and inner diameters as small as 250 mm and 120 µm, respectively. The versatility of these h‐LCE fibers across various applications are further demonstrated, from fast‐response stiffness‐tunable actuators by integrating water flow as triggering media and shape memory polymer (SMP) for enhanced mechanical properties, to electrically driven actuating systems through the incorporation of liquid metal, and actuating light‐guides by combining SMP and PDMS optical fiber. The conception of h‐LCE fiber not only advances the design of multifunctional LCE composites but also paves the way for their application in soft robotics, artificial muscles, and beyond. [ABSTRACT FROM AUTHOR]

Calcium sulfate whiskers (CSW) exhibit significant surface polarity and high surface energy, leading to aggregation when directly incorporated into polymer matrices, significantly affecting the mechanical properties of the composites. Sodium oleate (SO) was used to modify CSW, introducing –C=C– active groups on the surface, followed by in‐situ graft polymerization of sodium oleate‐modified CSW (SO‐CSW) with methyl methacrylate (MMA) to prepare CSW‐g‐PMMA composites. The modification mechanism of SO and PMMA on CSW, as well as the surface modification effects on CSW, were studied using DRIFT, XRD, XPS and TEM. The results show that oleic acid ions adsorb onto the surface of CSW in two forms. One is chemisorption, in which the oleic acid ions are adsorbed on the calcium ions site on the surface of CSW in a bridging way. The other is physical adsorption, oleic acid ions and dissolved calcium ions in the form of precipitation adsorbed on the outermost layer of CSW. After in‐situ polymerization, PMMA was successfully grafted onto the surface of CSW, and the thickness of the surface PMMA coating layer was approximately 67 nm. CSW‐g‐PMMA was used as a filler in the melt blending with polypropylene (PP) to prepare PP composites. CSW‐g‐PMMA mainly toughens and enhances the mechanical properties of PP composites in the form of crack bridging, crack deflection and pull‐out effect. Highlights: The mechanism of sodium oleate modified calcium sulfate whisker (CSW) has been investigated. One is chemical adsorption that the oleic acid ions are adsorbed on the calcium ions site on the CSW surface in a bridge way. The other is physical adsorption that oleic acid ions and dissolved calcium ions are adsorbed in the form of precipitation on the outer layer of CSW.After the modification of sodium oleate, the active group –C=C– was introduced on the surface of CSW, and then the PMMA long chain polymer was grafted with an in‐situ polymerization to form a PMMA coating layer with a thickness of about 67 nm, which significantly improved the hydrophobicity of CSW surface.After modification with sodium oleate and PMMA grafting, the modified CSW significantly toughened and enhanced the mechanical properties of PP composites in the form of crack bridging, crack deflection and pull‐out effect. [ABSTRACT FROM AUTHOR]

Endowing artificial muscles with perceptual function, as an octopus does, is highly desired but still suffering from interfacing mismatch between actuating and sensing units in a thin fiber. Herein, an artificial neuromuscular fiber capable of electrically responding to external strain/temperature and actuation path with power supply is reported by using polymer‐assisted metal deposition to firmly coat Cu nanoparticles on the surface of liquid crystal elastomer (LCE). The LCE core acts as an actuator, while the wrinkled Cu sheath provides environment interaction and actuation monitoring. Benefiting from the levodopa/polyethyleneimine interface design, this fiber exhibits large reversible contraction (47.61%), fast strain rate (370% s−1), high output power density (663.75 W kg−1) and reliable durability (1000 cycles) under electrical stimulation. Furthermore, by combining as‐made fiber arrays with electronic system and computing algorithm, this machine learning‐assisted artificial neuromuscular system can actuate the Chinese shadow puppetry and recognize its body movements with high accuracy. This work paves a revolutionary way for fabricating next‐generation flexible robots. [ABSTRACT FROM AUTHOR]

This study investigates the enhancement of mechanical and electrical properties of composite electrolyte membranes through the incorporation of polylactic acid (PLA) fibers and nanocrystalline cellulose (NCC) derived from kapok. PLA fibers were prepared using electrospinning, while kapok NCC was synthesized through pulping, bleaching, and hydrolysis. Scanning electron microscopy (SEM) analysis revealed an average PLA fiber diameter of 597 nm and a kapok NCC grain size of 70.2 nm. The composite electrolyte membranes were prepared by combining polyvinyl alcohol (PVA), potassium hydroxide (KOH), glycerol, and varying amounts of PLA/NCC reinforcement. Tensile tests showed that the addition of 0.05 g kapok NCC improved the tensile strength by 87.6% and increased elongation. Impedance analysis demonstrated a decrease in impedance with the incorporation of PLA and kapok NCC fibers, indicating enhanced conductivity. The sample with 0.05 g kapok NCC (FKP5) exhibited the highest conductivity of 0.068 mS/cm. Cyclic voltammetry revealed more pronounced reduction and oxidation reactions in FKP5, while electrical power measurements showed a maximum power of 12.6 mW for FKP5. The improved mechanical and electrical properties of the composite membranes containing PLA and kapok NCC highlight their potential for use in sustainable batteries and other industrial applications. [ABSTRACT FROM AUTHOR]

Perovskites with ultra‐low phonon energy have excellent radiation properties, while the population distribution of its luminescent initial state needs to be facilitated to further optimize the stokes fluorescence of Er3+ under high‐energy photons excitation. Herein, UV excitability of Er3+ is remodeled by building an energy transfer channel from Sb3+ to Er3+ in Cs2NaInCl6 (CNIC) microcrystal to realize the enhancement of stokes fluorescence of Er3+. Under UV excitation, the breakthrough boost of Er3+ is observed in Cs2NaInCl6:Sb3+‐Er3+ (CNIC:Sb‐Er), and the sensitization coefficient from Sb3+ to Er3+ in CNIC is derived to be as high as 112. Moreover, CNIC:Sb‐Er is embedded into functional fibers to enhance the crystal stability and the composite flexibility, which form fluorescence fibers with strong radiation transition probability. Finally, a high‐precision temperature sensing is achieved based on FIR (fluorescence intensity ratios) technology, and the maximum relative sensitivities of CNIC:Sb‐Er phosphors and CNIC:Sb‐Er/PAN fibers reach 1.13 and 1.10% K−1, respectively, indicating that CNIC:Sb‐Er and CNIC:Sb‐Er/PAN fibers have potential applications in optical temperature sensors. [ABSTRACT FROM AUTHOR]

Difficult-to-cut titanium matrix composites (TiB+TiC)/Ti6Al4V have extensive application prospects in the fields of biomedical and aerospace metal microcomponents due to their excellent mechanical properties. Jet electrochemical micromilling (JEMM) technology is an ideal method for machining microstructures that leverages the principle of electrochemical anodic dissolution. However, the matrix Ti6Al4V is susceptible to passivation during electrochemical milling, and the inclusion of high-strength TiB whiskers and TiC particles as reinforcing phases further increases the machining difficulty of (TiB+TiC)/Ti6Al4V. In this study, a novel approach using NaCl+NaNO3 mixed electrolyte for the JEMM of (TiB+TiC)/Ti6Al4V was adopted. Electrochemical behaviors were measured in NaCl and NaCl+NaNO3 electrolytes. In the mixed electrolyte, a higher transpassive potential was required to break down the passive film, which led to better corrosion resistance of (TiB+TiC)/Ti6Al4V, and the exposed reinforcing phases on the dissolved surface were significantly reduced. The results of the JEMM machining indicate that, compared to NaCl electrolyte, using mixed electrolyte effectively mitigates stray corrosion at the edges of micro-grooves and markedly improves the uniformity of both groove depth and width dimensions. Additionally, the surface quality was noticeably improved, with a reduction in Ra from 2.84 μm to 1.03 μm and in Rq from 3.41 μm to 1.40 μm. [ABSTRACT FROM AUTHOR]

Pack boriding with CeO2 was performed on the powder metallurgical (PM) near-α type titanium alloy at a temperature of 1273–1373 K for 5–15 h followed by air cooling. The microstructure analysis showed that the boride layer on the surface of the alloy was mainly composed of a monolithic TiB2 outer layer, inner whisker TiB and sub-micron sized flake-like TiB layer. The growth kinetics of the TiB2 and TiB layers obeyed the parabolic diffusion model. The diffusion coefficient of boron in the boride layers obtained in the present study was well within the ranges reported in the literature. The activation energies of boron in the TiB2 and TiB layers during the pack boriding were estimated to be 166.4 kJ/mol and 122.8 kJ/mol, respectively. Friction tests showed that alloys borided at moderate temperatures and times had lower friction coefficients, which may have been due to the fine grain strengthening effect of TiB whiskers. The alloy borided at 1273 K for 10 h had a minimum friction coefficient of 0.73. [ABSTRACT FROM AUTHOR]

The presence of organic contaminants in aquatic environments, such as antibiotics, induces the proliferation of resistant pathogens, giving rise to the need to develop new materials with antimicrobial action. Therefore, in this work, we report new results to purified Palygorskite (P-Pal) clay with a surface impregnated with alpha-silver tungstate (α-Ag 2 WO 4) microcrystals abbreviated as AWO, and its structural, photoluminescence (PL) and antibacterial investigation for inactivation of gram-negative (Escherichia coli) and gram-positive (Staphylococcus aureus) bacterial strains at concentrations of P-Pal/ x %/AWO from x = 4–32%. X-ray diffraction patterns, Rietveld refinement data, and Fourier transform infrared spectroscopy confirmed that the P-Pal is composed of two crystal phases (Mg 2.074 Al 1.026) (Si 4 O 10.48) 2 (OH) 2 (H 2 O) 10.68 with an orthorhombic structure and α-SiO 2 with a rhombohedral structure; already the AWO microcrystals are single-phase with an orthorhombic structure and their vibrational modes. Ultraviolet–visible spectroscopy shows an increase in the E gap values for mixed systems compared to the isolated materials, indicating a synergistic interaction between the energy levels of both materials. Field emission scanning electron microscopy images display the presence of several elongated fibers and hexagonal crystals in the P-Pal clay and rod-like AWO microcrystals. In contrast, P-Pal clay/AWO microcrystals exhibit the presence of all three crystal shapes. Photoluminescence spectra show a high emission for the P-Pal clay/4% AWO microcrystals, indicating a better energy band gap synergistic. Finally, the microbiological tests show that as the proportion of AWO crystals on the P-Pal clay surface increases, there is a rise in antibacterial activity. [ABSTRACT FROM AUTHOR]

The production of high-performance carbon fibers relies heavily on the structural transformations of polyacrylonitrile (PAN) fiber during processing. In this article differential scanning calorimetry (DSC), synchrotron small-angle X-ray scattering (SAXS), and synchrotron wide-angle X-ray diffraction (WAXD) were used to study the changes of the thermal properties, voids and crystal structure of the PAN precursor fibers on industrial lines during the continuous processing stages, i.e., after the treatment in the coagulation bath, after stretching in boiling water and after stretching in high-temperature steam. The findings of this study suggest that after boiling water stretching the molecular chain motion of the PAN precursor fiber weaken, resulting in the expansion of the voids. After high-temperature steam stretching the voids became elliptical and oriented in the stretching direction. Although the boiling water stretching process partially damaged the (100) crystal planes of the PAN precursor fibers, it does not hinder their overall crystalline structure. The high stretching ratio primarily affected the orientation of the molecular chains. This orientation, even in the context of partial crystal plane disruption, further promoted the crystallization of the (100) crystal planes in the fibers. These experiments explored the correlation between the processing technology and fiber structure transformation of PAN-based carbon fibers, resulting in producing a guide for the preparation of high-performance carbon fibers with fewer defects. [ABSTRACT FROM AUTHOR]

The effects of soluble ions on the morphology and crystal growth of calcium sulfate hemihydrate whiskers are very significant. In order to gain a deeper understanding of the basic theory of regulating whiskers, this paper summarises the progress of research on the effects of different types and concentrations of soluble cations in desulfurization gypsum on the whisker preparation. The low concentration of Na+ has a small effect on the calcium sulfate hemihydrate whiskers and barely affects the morphology and surface smoothness of the whiskers. The content of K+ is suitable to be 3% (mass fraction) or below, and the higher content has a detrimental effect on the growth of calcium sulfate hemihydrate whiskers. Mg2+ makes the whisker surface more homogeneous and crystalline. And the trace amount of selective adsorption of Al3+ has no effect on the whisker length-to-diameter ratio. Similar to K+, Fe3+ also has the optimal concentration, which is lower than 2 mmol / L. Unlike the cations mentioned above, Cu2+ is not from the raw material, but is an additional ion introduced in the doping of the appropriate amount of Cu2+ is conducive to the formation of whiskers with a smooth and uniform surface. [ABSTRACT FROM AUTHOR]

A tunable continuous wave (CW) Yb:CaWO4 laser operating in near infrared (NIR) spectral region is demonstrated by pumping with a diode laser. Continuously broadband tunable wavelengths are obtained in two polarizations by rotating the Lyot filter. The tuning widths of the output wavelengths in the π- and σ-polarizations are 42 nm (from 1005.2 nm to 1047.2 nm) and 41.8 nm (from 1005.1 nm to 1046.9 nm), respectively. At an absorbed pump power of 15.6 W at 976 nm, the maximum output powers in the π- and σ-polarizations are 5.2 W at 1026.2 nm and 4.7 W at 1028.1 nm, respectively. To the best of our knowledge, this is the first tunable laser operation by using Yb:CaWO4 crystal. [ABSTRACT FROM AUTHOR]

Maintaining both high sensitivity and large figure of merit (FoM) is crucial in regard to the performance of optical devices, particularly when they are intended for use as biosensors with extremely low limit of detection (LoD). Here, a stack of nano‐assembled layers in the form of 1D photonic crystal, deposited on D‐shaped single‐mode fibers, is created to meet these criteria, resulting in the generation of Bloch surface wave resonances. The increase in the contrast between high and low refractive index (RI) nano‐layers, along with the reduction of losses, enables not only to achieve high sensitivity, but also a narrowed resonance bandwidth, leading to a significant enhancement in the FoM. Preliminary testing for bulk RI sensitivity is carried out, and the effect of an additional nano‐layer that mimics a biological layer where binding interactions occur is also considered. Finally, the biosensing capability is assessed by detecting immunoglobulin G in serum at very low concentrations, and a record LoD of 70 aM is achieved. An optical fiber biosensor that is capable of attaining extraordinarily low LoD in the attomolar range is not only a remarkable technical outcome, but can also be envisaged as a powerful tool for early diagnosis of diseases. [ABSTRACT FROM AUTHOR]

Liquid crystal elastomer (LCE) has large and reversible deformation under stimulation, making it an ideal material for artificial muscles. Currently, multi‐stimulus responsive LCE actually responds to each stimulus independently rather than responding to several stimuli simultaneously. Achieving an enhanced effect from concurrent stimuli is still a challenge, which requires a new stimulus‐response mechanism. This work develops a novel and facile solvent evaporation‐assisted template method to prepare LCE hollow fiber (LCEHF) with axial alignment. Taking advantage of the enhanced effect of heat‐induced phase transition and mechanical force‐induced orientation transition of mesogens, the LCEHF under both heat and pressure can produce a large contraction ratio of ≈50%, which is higher than 42% of thermal stimulation or 27% of pneumatic stimulation. It can also enhance the respective response and recovery speed of LCEHF to 300 and 3700 times of pneumatic actuation. Additionally, the enhanced effect lowers the actuation temperature much below the phase transition temperature, imparting LCEHF with high mechanical performance during actuation. Furthermore, the dual thermal‐pneumatic responsive LCEHF can mimic human biceps and cause large and rapid bending of an artificial arm reversibly. This new actuation methodology sheds new light on improving LCE actuation performance and broadens its application scenarios. [ABSTRACT FROM AUTHOR]

This paper presents interactive liquid crystal fiber arrays that can actuate in a way perceptible by human touch. The fibers are actuated via a computer interface, enabling precise control over actuation direction, magnitude, and frequency. Unlike conventional methods, our technique initiates the actuation at the base of the fibers, which is enabled by fabricating the fibers directly onto an electrical circuit. Fiber actuation is achieved by localized addressing of an in situ formed radially aligned segment. This induces reduction in the scalar order parameter and leads to deformation of the fiber base, causing bending toward the activated region. Extensive modeling validates this actuation mechanism and identifies optimal conditions and actuation strategies for achieving the desired responses. The actuation process is rapid, is highly reversible, and maintains excellent performance over repeated (>200) cycles. These liquid crystal fiber arrays provide a safe contact with humans or other objects, making them highly suitable for applications in smart wearable devices and immersive interfaces. [ABSTRACT FROM AUTHOR]

Magnesium borate whiskers were used to prepare a hierarchical microstructure on cordierite ceramic substrate through the precipitation-molten salt method. The La 2-X Ce X Zr 2 O 7 catalyst was then loaded onto the magnesium borate whiskers to form the hierarchical microstructure. The Ce-doped catalysts exhibited a significant improvement in the catalytic activity of soot combustion compared to the La 2 Zr 2 O 7 catalyst. The study employed various techniques to characterize the structural morphology and phase composition, including scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), Fourier transform-infrared spectroscopy (FT-IR), and X-ray diffraction (XRD). The growth of Magnesium borate whiskers (Mg 2 B 2 O 5) with diameters of 100–200 nm and lengths of 2–5 μm were grown and tightly bonded to the cordierite ceramic substrate to mimic the structure of human respiratory system cilia. This could improve the filtration efficiency of soot in car exhaust. BET analysis showed that the specific surface area of cordierite increased from 0.684 m2/g to 1.363 m2/g after whisker growth. The study confirmed that the whiskers were firmly attached to the cordierite ceramic substrate, as demonstrated by the binding strength experiments. The addition of Ce metal has been found to significantly enhance soot combustion due to the presence of more active oxygen species and superior mobility of lattice oxygen species with more oxygen vacancies. The catalyst's intrinsic redox property was characterized using X-ray photoelectron spectroscopy (XPS) and H 2 temperature-programmed reduction (H 2 -TPR). The semi-quantitative thermogravimetric analysis (TG-DTG) and the temperature-programmed oxidation (TPO) of catalysts showed that Z-La 1.9 Ce 0 · 1 Zr 2 O 7 exhibited the highest catalytic activity for soot combustion, with an ignition temperature of 268 °C, a peak temperature of 418 °C, and a temperature of 90 % soot conversion of 464 °C. Furthermore, cyclic stability experiments demonstrate that the Z-La 1.9 Ce 0 · 1 Zr 2 O 7 catalyst exhibits excellent structural stability and consistent catalytic performance. This distinctive microstructure holds great potential for applications in the field of DPF. [ABSTRACT FROM AUTHOR]

• LNF exhibited a high freezing rate and contributed to small ice crystal forming. • LNF maintained WHC and shear force of Monopterus albus. • LNF alleviated myofibrillar protein denaturation of Monopterus albus. • LNF at −110 °C is more suitable for Monopterus albus than LNF at −50 °C and −80 °C. Monopterus albus is highly susceptible to spoilage due to high protein and moisture contents while frozen storage can effectively prolong the shelf-life. To study the effect of liquid nitrogen freezing (LNF) on quality, microstructure of ice crystal and muscle fiber, and physicochemical properties of proteins, Monopterus albus was frozen at -20 °C by refrigerator (RF, control), -50 °C, -80 °C, and -110 °C by LNF, respectively. The -110 °C LNF exhibited the highest freezing rate among four groups, contributing to the formation of small ice crystals with more uniform distribution and alleviating the damage to muscle fiber. In -110 °C LNF group, protein secondary structure changed relatively subtle, resulting in high protein solubility, Ca2+-ATPase activity, and total sulfhydryl content, as well as low surface hydrophobicity and disulfide bond content. LNF retarded the rise of TVB-N value, prevented the loss of immobilized and free water, and maintained water holding capacity and shear force. In conclusion, -110 °C LNF was recommended a promising freezing process for frozen Monopterus albus due to less alteration of quality and alleviation of protein denaturation. [Display omitted] [ABSTRACT FROM AUTHOR]

The green and efficient use of coal gangue (CG) is urgently required in the Chinese coal industry to avoid its adverse environmental impact. This study proposed an Al-assisted carbothermal reduction method to synthesise SiC–Al 2 O 3 ceramics using high-C CG. The optimised experimental conditions for sintering SiC and their effects on the phase composition and related properties of the composites were investigated. The addition of Al optimised the in-situ synthesis pathway of SiC and significantly improved the carbothermal reaction efficiency, making the reactive temperature decrease from 1500 to 1200 °C. Additionally, sintering temperatures could modulate the SiC morphology by affecting the generation of SiO (gas) and the liquid phase of melting Al. The H3 formulation sintered at 900 °C was appropriate for producing SiC w /Al 2 O 3 ceramics with a bending strength of 49.24 MPa, a thermal conductivity of 1.720 W (m K)−1 and good thermal shock resistance (no cracks forming after 20 cycles). This study aimed to fully combine the reactivity changes of CG with the melting reduction reaction of Al. Findings in this work offer novel insights into the synthesis of structural ceramics and the cleaner use of CG for solar thermal storage. [ABSTRACT FROM AUTHOR]

A TiN whisker toughening TiB 2 based ceramic composite was fabricated by spark plasma sintering (SPS). The influence of sintering temperature and holding time on the microstructure and mechanical properties of the composite was investigated. The results indicate that, at a sintering temperature of 1500 °C and a holding time of 9 min, the composite exhibits a relative density of 99.24 %, flexural strength of 906 MPa, fracture toughness of 8.6 MPa m1/2, and Vickers hardness of 22.3 GPa. The sintering aid composed of Ni and Mo within the composite significantly enhanced atomic diffusivity in TiB 2 grains, promoting a balanced grain growth rate. SPS technology promoted the rapid formation of numerous necks between TiB 2 grains in a very short duration. Concurrently, the pinning effect exerted by TiN whiskers effectively inhibited excessively rapid migration of grain boundaries. These factors ensured that the composite could achieve optimized microstructures and good mechanical properties at a low sintering temperature. [ABSTRACT FROM AUTHOR]

Ceramic whiskers exhibit excellent performance due to their special structure, making them widely used in the field of refractories. In this work, a novel Al 4 SiC 4 whisker was designed to improve the mechanical properties and thermal shock resistance of Al 2 O 3 –SiC–C (ASC) refractories. By introducing nickel nitrate as a catalyst, the Al 4 SiC 4 whiskers with a special "stalactite" structure could be directly grown in situ at the operating temperature of ASC (1450 °C). Combining the experimental results and first-principles calculations, the AlNi 2 Si alloy formed during the heat treatment process acted as catalyst sites, AlO, SiO and CO were easily absorbed on the Ni 55 surface. Subsequently, the Al–O, Si–O and C–O bonds were broken and reacted with each other to grow Al 4 SiC 4 whiskers according to the vapor-liquid-solid mechanism. As expected, the incorporation of Al 4 SiC 4 whiskers resulted in a 57.4 % increase in cold compressive strength (CCS) and a 47.2 % increase in residual strength ratio (RSR) of the ASC refractories due to the strengthening mechanism of whisker bridging. This study presents a novel research strategy for enhancing the properties of refractories. [ABSTRACT FROM AUTHOR]

Aluminum nitride (AlN), prized for its high thermal conductivity and electronic insulating properties, finds widespread use in electronic applications, particularly as a substrate material. However, its relatively low fracture toughness limits its application. In this study, to enhance both the thermal and mechanical properties of AlN ceramics, we thoroughly investigate the microstructure, thermal, and mechanical properties of self-reinforced AlN ceramics fabricated by spark plasma sintering, with self-reinforcement achieved through the integration of AlN whiskers within the AlN matrix. Unlike previous studies utilizing conventional pressureless sintering with limited sintering conditions, this work employs spark plasma sintering with a wide range of temperatures (1600–1900 °C) and holding times (10–30 min), providing a comprehensive understanding of the sintering behavior. Microstructural features, observed through optical and scanning electron microscopy, reveal distinct toughening mechanisms via crack deflection and branching, with a maximum 20% enhancement. The self-reinforced AlN ceramics exhibit remarkable improvements in thermal conductivity, reaching up to 150 W m−1 K−1, surpassing reported values for spark plasma-sintered AlN ceramics. Adding AlN whiskers enhances the thermal and mechanical properties of AlN simultaneously, particularly at 1800 °C for 10 min with controlled grain size and nicely integrated AlN whiskers. This work not only contributes valuable insights into the complex relationship between processing parameters, microstructure, and resulting thermal and mechanical properties but also highlights the enhanced thermal and mechanical properties of self-reinforced AlN ceramics. [ABSTRACT FROM AUTHOR]

Regulation on one-dimensional growth has been a major challenge for the preparation of high quality zirconia whiskers. In the present work, high-aspect ratio zirconia whiskers were successfully synthesized via molten salt method. The effect of soaking time on the aspect ratio and growth behaviour of zirconia whiskers was studied. The results suggested that the average aspect ratio of zirconia whiskers reached to 42 at 15 h. The zirconia whiskers grew along [100] direction. The entire process can be divided into an initial slow stage, a rapid growth stage and a declining stage. The dissolution–precipitation of Na9-4xZrx(PO4)3 is the key factor in the initial slow stage. The rapid growth stage of zirconia whiskers is highly dependent on the directional adsorption of F− and screw dislocation step. In the declining stage, the drastic transformation of whiskers morphology from fibrous shape to rod-like and granular ones is caused by excessive volatilization of Na3PO4·12H2O and NaF molten salts. [ABSTRACT FROM AUTHOR]

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Herein, we investigate the effect of the addition of tetra‐needle‐like zinc oxide whisker (T‐ZnOw), a novel reinforcing additive, on the melt crystallization behavior of biodegradable polybutylene adipate terephthalate (PBAT)/polylactic acid (PLA) polymer blends. PBAT and PLA were blended in a Haake mixer at a fixed weight ratio of 70/30, and the contents of T‐ZnOw varied from 0 to 7 wt%. The melt thermal properties and crystallization behavior of PBAT/PLA blends and PBAT/PLA/T‐ZnOw composites were studied using differential scanning calorimetry. The kinetics of melt crystallization have been quantitatively explained using a range of mathematical formalisms. The Avrami equation is adopted to analyze the isothermal crystallization process and kinetics of PBAT/PLA/T‐ZnOw composites. For its nonisothermal crystallization process and kinetics, the Ozawa equation cannot describe the entire process, while the Jeziomy‐modified Avrami equation can only describe the initial stage of its nonisothermal crystallization. Using Mo‐analysis, the impact of T‐ZnOw contents on the composite's nonisothermal crystallization kinetic has been thoroughly examined. Given that the PBAT/PLA blend system's crystal formation may be inhibited by T‐ZnOw, the observation demonstrates that T‐ZnOw only marginally alters this process. The work is of significant scientific value and adds a new concept to the development of sustainable thin film for packaging. Highlights: T‐ZnOw is used as a novel additive for PBAT/PLA polymer blends.The crystallization of PBAT/PLA/T‐ZnOw composite systems is thoroughly examined.T‐ZnOw marginally reduces the kinetics of the crystallization process of PBAT/PLA blends.PBAT/PLA/T‐ZnOw composites follow volume nucleation with mixed 2D/1D growth.The nonisothermal crystallization of PBAT/PLA/T‐ZnOw composites is validated by Mo‐analysis. [ABSTRACT FROM AUTHOR]

Hydrogen bonding is the prerequisite for polyamide fibers to have better stress–strain behavior. It affects the crystal structure of polyamide fibers, such as orientation and periodic arrangement. To illustrate the effect of intermolecular hydrogen bonding on fiber orientation structure and macroscopic mechanical properties, this work uses conventional polyamide resin doped with high molecular weight components to construct polymer compounds with discrete distribution characteristics. By analyzing the changes in intermolecular hydrogen bonds, melt rheological properties, non‐isothermal crystallization behaviors, the impact of hydrogen bonds on the crystal structure and orientation structure and thus on the fiber strength was clarified. The doping of high molecular weight components can make the compound form more hydrogen bonds and inhibit the relaxation of molecular chains through entanglement, thereby promoting melt non‐isothermal crystallization process and increasing complex viscosity η* and storage mode G'. 1D and 2D wide‐angle and small‐angle X‐ray scattering show that doping components reduce crystal size of α1(200) and α2(002, 202) planes from 4.19 to 3.47 nm and 5.88 to 4.96 nm, resulting in a denser long‐period structure. Through the strategy of this work, polyamide 6 fibers' tensile strength is effectively improved by18%, and the mechanical properties are significantly improved. Highlights: High‐strength polyamide compound fibers were prepared.Discretely distributed compounds are achieved.Discretely distributed molecular weight enabled hydrogen bonding regulation.Hydrogen bonding‐induced compound fiber crystal structure.Multiple external fields induced crystallization and orientation structures. [ABSTRACT FROM AUTHOR]

Commercially pure titanium was plasma paste borided using various temperatures of the process. An increase in the boriding temperature resulted in an increase in the thickness of the borided layer. All the layers produced consisted of an outer compact TiB2 zone and an inner TiB zone in the form of whiskers penetrating into the substrate. The presence of hard titanium borides resulted in a significant increase in wear resistance compared to non-borided pure titanium. However, the thickness of the layer produced strongly influenced the wear behavior, in respect of the time required for complete destruction of the layer. Higher wear resistance was characteristic of the TiB2 layer due to its compact nature, whereas the specific morphology of TiB whiskers resulted in their lower wear resistance compared to the outer TiB2 layer. Plasma paste boriding of pure titanium also had an advantageous effect on corrosion resistance compared to non-borided pure titanium. Simultaneously, due to the higher thickness of TiB2 layer, the specimen borided at a higher temperature showed higher corrosion resistance. [ABSTRACT FROM AUTHOR]

In this paper, linear low-density polyethylene (LLDPE) fibers were stabilized by ultraviolet ray (UV) irradiation, which provided a new treatment method for fabricating carbon fiber precursors. LLDPE chips were blended with a photo-initiator 4-chlorobenzophenone (4-CBP) and a crosslinker 1,2-polybutadiene (1,2-PB) to obtain spun particles, and then they were melt spun into the fibers. Then, UV irradiation of the as-spun fibers was performed to obtain precursors. An orthogonal experimental design investigated the effects of the ingredient ratio LLDPE:1,2-PB and UV irradiation time on the fiber gelation. The results show that the factor's order of influence was: ingredient ratio > UV irradiation time. The fiber gelation reaches a maximum of 67.51% at a dosage ratio of LLDPE:1, 2-PB of 97:2, and a UV irradiation time of 30 min. The UV irradiation introduced the crosslinking structure of LLDPE fibers, and the melting temperature of UV-XLPE fibers shifts toward lower temperatures, and the crystal size of the fibers decreased with increasing UV irradiation time. However, longer irradiation time does not beneficially affect the gelation degree. The low cost and feasible crosslinking method in this study offer the possibility of wide application of low-cost polyethylene-based carbon fibers. [ABSTRACT FROM AUTHOR]

In this paper, we propose an innovative light-powered LCE-slider system that enables continuous self-circling on an elliptical track and is comprised of a light-powered LCE string, slider, and rigid elliptical track. By formulating and solving dimensionless dynamic equations, we explain static and self-circling states, emphasizing self-circling dynamics and energy balance. Quantitative analysis reveals that the self-circling frequency of LCE-slider systems is independent of the initial tangential velocity but sensitive to light intensity, contraction coefficients, elastic coefficients, the elliptical axis ratio, and damping coefficients. Notably, elliptical motion outperforms circular motion in angular velocity and frequency, indicating greater efficiency. Reliable self-circling under constant light suggests applications in periodic motion fields, especially celestial mechanics. Additionally, the system's remarkable adaptability to a wide range of curved trajectories exemplifies its flexibility and versatility, while its energy absorption and conversion capabilities position it as a highly potential candidate for applications in robotics, construction, and transportation. [ABSTRACT FROM AUTHOR]

The use of direct ink writing technology, combined with in-situ grown whiskers, has facilitated the development of 3D-printed ceramic catalyst supports-aluminum borate porous ceramics (ABPCs) with hierarchical pore structures. The optimal slurry consists of 0.2 wt% polycarboxylate, 19 wt% water addition, and 1.2 wt% sodium alginate. The most effective printing parameters are determined to be a 1.0 mm nozzle diameter, 10 mm/s printing speed, 4.0 kPa air pressure, and 0.4 mm layer height. After sintering at 1100 ℃, pure-phase aluminum borate (Al 18 B 4 O 33) ceramics are achieved, leading to the formation of needle-like aluminum borate whiskers. The aspect ratio of whiskers, flexural strength, BET-specific surface area, and photocatalytic activity of ABPCs increase initially and then decrease with increasing sintering temperature. The ABPCs coated with a titanium oxide layer display a photocatalytic degradation rate of 83.92% for methyl orange solution. These results underscore the immense potential of ABPCs in high-temperature catalyst support applications. [ABSTRACT FROM AUTHOR]

The new ludwigite-group mineral savelievaite, ideally Mg2Cr3+O2(BO3), was found in the chromitite body at the Malaya Kharamatalou river valley, Voikar–Syninskiy ultrabasic complex, Polar Urals, Russia. Savelievaite and Cr-enriched ludwigite occur in clinochlore veinlets and are associated with earlier magnesiochromite, spinel, chromite, pargasite, diopside, forsterite, serpentine, magnetite and pentlandite. Savelievaite forms prismatic, acicular or fibrous crystals up to 0.05 × 0.4 mm, usually assembled in radiating or chaotic clusters up to 1 × 1.5 mm across. It is opaque, black to greenish-black. The lustre is vitreous for prismatic crystals and silky for fibrous aggregates. D (calc.) = 3.91 g cm–3. Under the microscope in reflected light, savelievaite is grey, non-pleochroic, with weak bireflectance and anisotropism. The chemical composition (wt.%, EMPA, Fe2+:Fe3+ ratio by stoichiometry) is: MgO 34.88, FeO 10.83, NiO 0.36, B2O3 16.80, Al2O3 2.97, V2O3 0.21, Cr2O3 21.97, Fe2O3 12.40, TiO2 0.43, total 100.85. The empirical formula calculated on the basis of 5 O apfu is (Mg1.72Fe2+0.30Ni0.01)Σ2.03(Cr3+0.57Fe3+0.31Al0.12Ti0.01V3+0.01)Σ1.02B0.96O5. Savelievaite is orthorhombic, space group Pbam , a = 9.2631(6), b = 12.2298(8), c = 3.0104(2) Å, V = 341.04(4) Å3 and Z = 4. The strongest reflections of the powder X-ray diffraction pattern [ d ,Å(I)(hkl)] are: 5.101(100)(120); 2.551(90)(240); 2.524(88)(201); 2.163(36)(250); and 2.033(55)(321). The crystal structure was solved from single-crystal X-ray diffraction data and refined to R 1 = 0.0405. Savelievaite is isostructural with ludwigite, Cr3+ is concentrated at the M 4 site. The mineral is named in honour of the Russian petrologist and geologist Dr. Galina Nikolaevna Savelieva (b. 1936). Ludwigite, ideally Mg2Fe3+O2(BO3), and savelievaite form a continuous isomorphous series in which Cr3+ content varies from 0 to 0.60 apfu. Occurrences of Cr-enriched (>1 wt.% Cr2O3) varieties of ludwigite are mainly related to ultrabasic complexes. The Cr-richest (>10 wt.% Cr2O3) ludwigite–savelievaite-series members are found in chromite ores at the Voikar–Syninskiy complex and Volchiegorskoe and Tatishchevskoe deposits, both in the South Urals. [ABSTRACT FROM AUTHOR]

Based on mortar composites with a low water–cement ratio, the effects of hybrid aramid fiber (AF), calcium sulfate whisker (CSW), and basalt fiber (BF) on their mechanical properties and wear resistance were studied, and the correlation between wear resistance and compressive strength are discussed. A microstructure analysis was conducted through scanning electron microscopy (SEM) and the nitrogen-adsorption method (BET). The research results show that compared with the control group, the compressive strength, flexural strength, and wear resistance of the hybrid AF, CSW, and BF mortar composites with a low water–cement ratio increased by up to 33.6%, 32%, and 40.8%, respectively; there is a certain linear trend between wear resistance and compressive strength, but the discreteness is large. The microstructure analysis shows that CSW, AF, and BF mainly dissipate energy through bonding, friction, mechanical interlocking with the mortar matrix, and their own pull out and fracture, thereby enhancing and toughening the mortar. A single doping of CSW and co-doping of CSW and AF can refine the pore structure of the mortar, making the mortar structure more compact. [ABSTRACT FROM AUTHOR]

Structural color is a remarkable physical phenomenon that exists widely in nature. Unlike traditional color rendering methods, they are realized mainly through micro/nanostructures that interfere, diffract, scatter light, and exhibit long‐life and environmental‐friendly color effects. In nature, a few organisms use their color‐changing system to transmit information, such as courtship, warning, or disguise. Meanwhile, some natural inorganic minerals can also exhibit structural colors. Learning from nature, scientists have achieved large‐scale structural color design and manufacturing technology for artificial photonic crystals. Photonic crystals have a unique microstructure that forms a band gap under the action of the periodic potential field, consequently causing Bragg scattering due to the periodic arrangement of different refractive index media within them. Because of the apparent photonic band gap and the ability to form local photons at crystal defects, photonic crystals have been extensively studied in recent years and have broad application prospects in photonic fibers, optical computers, chips, and other fields. In this review, the research, properties, and applications of photonic crystals in recent years are presented, as well as insight into the future developments of photonic crystals. [ABSTRACT FROM AUTHOR]

Silicon carbide whiskers (SiCw) were used as reinforcing fillers in high-density polyethylene (HDPE) to prepare high-density polyethylene/silicon carbide whiskers (HDPE/SiCw) composites. By characterizing and analyzing the thermal conductivity, Vicat softening temperature, thermal and mechanical properties of HDPE/SiCw composites, the influence of SiCw content on the mechanical and thermal conductivity of HDPE composites is explored. The results showed that with the increase of SiCw content, the thermal conductivity of HDPE composites continued to increase, and the melting temperature Tm and enthalpy ΔH both continued to increase. The thermal stability of HDPE composites has been effectively improved. At the same time, the Vicat softening temperature of HDPE composites shows a trend of first increasing and then slightly decreasing. The elastic modulus, yield strength, and fracture strength of HDPE composites all show a trend of first increasing and then fluctuating or stable changes, while the elongation at break shows a decreasing trend. When the SiCw content is 30%, the thermal conductivity of HDPE/SiCw composites is 0.85 W/(m⋅K), the melting temperature Tm and enthalpy ΔH were 144.12 °C and 162.1 J/g, respectively. The elastic modulus, yield strength, and fracture strength of HDPE composites were 1 301.0, 36.5, 22.4 MPa, respectively, increased by 47.51%, 36.70%, 57.75%, respectively compared with pure HDPE. [ABSTRACT FROM AUTHOR]