Unlike bulk materials, nanomaterials usually exhibit differences in their structures and properties. In this paper, we have performed a comparative investigation on the pressure- and laser-induced responses of sulfur in its bulk state and nano state which is confined in nanopores of CMK-3. In Raman study, the influences of laser irradiation and nanoconfinement on the pressure-induced structural evolutions and the reversibilities of sulfur have been discussed. Under high pressure, sufficient laser irradiation with high power density facilitates the transformation of bulk sulfur into a crystalline phase rather than an amorphous state. In the nanospaces of CMK-3, S-I phase with deformed S8 rings amorphizes or transforms to S-II at lower pressures and then further transformations to high pressure phases (S-VI, S-III) are delayed due to the nanoconfinement effect. Upon decompression from the amorphous state, the confined sulfur exhibits a greater tendency to revert back to ring-like structures. However, once the high pressure phases with spiral chains are formed under high pressures, chain-like structures become dominant in the released samples. In X-ray diffraction (XRD) study, it is possible that orthorhombic S-I phase undergoes a pressure-induced isostructural transformation in both bulk and confined states. This transformation completes at around 12 GPa, accompanied by reorientation or ordering of S8 rings. The compressibility of sulfur confined in CMK-3 is suppressed in the ab-plane due to spatial constraints, whereas a slight enhancement is observed along the c-axis. This abnormal compressible behavior leads to a 38.7 % increase in the bulk modulus of the confined sulfur. This study not only sheds new light on the pressure- and photo-induced behaviors of the confined sulfur species, but also expands the phase diagram of sulfur under external stimuli to the nanoscale regime and demonstrates the applicability of sulfur filled CMK-3 (S@CMK-3) composites in the field of functionalized lithium-sulfur (Li-S) batteries under external pressure and irradiation stimuli.

Conventional hydrogels are generally constrained by their low electrical conductivity and limited functionality, which significantly hinders their application in flexible electronics. To overcome these limitations, this study reports a multifunctional hydrogel composite fabricated through a synergistic strategy combining cyclic freeze-thaw and salting-out processes. The resulting material exhibits ultrahigh electrical conductivity of 926 S cm-1, tensile strain of 700 %, Young's modulus of 2.63 MPa, and toughness of 24.3 MJ m-3. A key innovation is the engineering of a gradient concentration distribution of AgNWs within the PVA matrix, which enables tunable strain sensitivity. This gradient design endows the hydrogel with a distinctive negative resistance-strain relationship and a broadly tunable gauge factor reaching up to 983. The composite demonstrates broad application potential in areas such as flexible sensors, underwater flexible circuits, and high-power robotic arms. Furthermore, the material exhibits recyclability, retaining over 90 % of its original performance after recycling and reprocessing. This material system presents a new technical pathway for the development of next-generation sustainable flexible electronic devices.

OBJECTIVE:Brain development during childhood involves significant structural, functional, and connectivity changes, reflecting the interplay between modularity, information interaction, and functional segregation. This study aims to understand the dynamic properties of brain connectivity and their impact on cognitive development, focusing on temporal co-occurrence diversity patterns. METHODS:We recruited 481 children aged 6 to 12 years from the Healthy Brain Network database. Functional MRI data were used to construct dynamic functional connectivity matrices with a sliding window approach. Modular structures were identified using multilayer network community detection, and the Dagum Gini coefficient decomposition technique, which uniquely allows for multi-faceted exploration of modular temporal co-occurrence diversities, quantified these diversities. Mediation analysis assessed the impact on small-world properties. RESULTS:Temporal co-occurrence diversity in brain networks increased with age, especially in the default mode, frontoparietal, and salience networks. These changes were driven by disparities within and between communities. The small-world coefficient increased with age, indicating improved information processing efficiency. To validate the impact of changes in spatiotemporal interaction disparities during childhood on information transmission within brain networks, we used mediation analysis to verify its effect on alterations in small-world properties. CONCLUSION:This study highlights the critical developmental changes in brain modularity and spatiotemporal interaction patterns during childhood, emphasizing their role in cognitive maturation. These insights into neural mechanisms can inform the diagnosis and intervention of developmental disorders.

The utilization of photocatalytic technology to degrade contaminants such as heavy metals and antibiotics holds immense significance. Nevertheless, the pursuit of highly efficient photocatalysts remains a formidable challenge. Herein, a series of Sn3O4/TiO2 (ST) hybrid photocatalysts composed of TiO2 nanoparticles (NPs) and Sn3O4 nanosheets (NSs) have been designed and constructed to enhance the reduction of Cr(VI) and the degradation of ISN. TiO2 NPs were loaded onto the 2D layered flowerlike Sn3O4 NSs uniformly through a solvothermal approach, resulting in unique three-dimensional (3D) heterostructures. As expected, all ST composites exhibit higher degradation activity compared to pristine Sn3O4 and TiO2. The optimal ST-0.6 composite (with a TTIP amount of 0.6 g) possesses the highest degradation rate, achieving a 99.6 % removal for Cr(VI) within 60 min under Xenon light irradiation, with a rate constant (k) of 0.091 min-1. This performance surpasses that of pristine Sn3O4 and TiO2, which have rate constants of 0.0199 min-1 and 0.0186 min-1. Additionally, the ST-0.6 composite effectively removes 72.8 % for isoniazid (ISN) within 80 min. It exhibits the highest photodegradation rate of 0.014 min-1, being 1.3 and 140 times higher than that of TiO2 (0.0107 min-1) and Sn3O4 (0.0001 min-1), respectively. Furthermore, the photocatalytic degradation activities of the recovered samples retain their photocatalytic degradation performance after three consecutive experimental cycles, indicating relatively excellent durability. According to the photocatalytic and characterization results, the significantly enhanced photoactivity of the ST hybrid photocatalyst is attributed to the increased reaction sites, improved light-harvesting properties, and enhanced separation and transfer efficiency of photogenerated electrons and holes within the ST heterostructures.

Air pollutants, such as particulate matter (PM) and ammonia (NH3), generated by intensive animal farming pose considerable threats to human health, animal welfare, and ecological balance. Conventional materials are often ineffective at simultaneously removing multiple pollutants, maintaining a low pressure drop, and ensuring durability in heavily polluted environments. Inspired by the dust-retention properties of Pinus sylvestris var. mongolica (PS) needles, this study developed a biomimetic grooved ribbon fiber using electrospinning technology. These fibers were further assembled into a three-dimensional bioinspired aerogel structure through freeze-forming technology to achieve efficient dust capture. Additionally, the introduction of UiO-66-NH2 nanoparticles significantly enhanced the properties of the aerogels for NH3 adsorption. Among the various prepared aerogels (PG, UPG-5, UPG-10, UPG-15, and UPG-20), UPG-10 demonstrated the best performance, achieving a filtration efficiency of 99.24% with a pressure drop of 95 Pa. Notably, it exhibited a remarkable dust-holding capacity of 147 g/m2, and its NH3 adsorption capacity reached 99.89 cm3/g, surpassing PG aerogel by 31.46 cm3/g. Additionally, UPG-10 exhibited outstanding elasticity, maintaining over 80% of its original shape after 30 compression cycles. This biomimetic aerogel presents a promising solution for air purification, contributing to improved agricultural efficiency and environmental sustainability.

Erbium-doped aluminum nitride (AlN:Er3+) pine-shaped nanostructures are synthesized, through a direct reaction between aluminum (Al) and erbium oxide (Er2O3) mixed powders in a nitrogen (N-2) atmosphere, by using a direct current arc discharge plasma method. X-ray diffraction (XRD) analysis reveals that the diffraction peaks of AlN:Er3+ shift towards lower angles for the doped sample compared with those of undoped AlN, indicating lattice expansion due to Er3+ incorporation. X-ray photoelectron spectroscopy (XPS) confirms that Al, N, and Er are coexistent, while energy-dispersive X-ray spectroscopy (EDS) quantitatively shows that the atomic ratio for Al:N:Er is about 46.9 & ratio;52.8 & ratio;0.3. The nanostructures, resembling pine trees, are measured to be 5-10 mu m in height and 1-3 mu m in width, with branch nanowires extending 500 nm-1 mu m in length and 50-100 nm in diameter. These branches, radiating at about 60 degrees from the main trunk, are found to grow along the [100] direction of wurtzite-structured AlN, as evidenced by high-resolution transmission electron microscopy (HRTEM) showing lattice spacing of 0.27 nm corresponding to the (100) plane. Photoluminescence studies identify distinct emission peaks in the visible region (527, 548, and 679 nm) and near-infrared region (801, 871, and 977 nm), which is attributed to intra-4f electron transitions of Er3+ ions. The average lifetime of the excited state at 548 nm is measured to be 9.63 mu s, slightly shorter than those of other Er3+-doped materials. The nanostructures demonstrate that the superior temperature sensing capability possesses a maximum relative sensitivity of 1.9x10(-2) K-1 at 293 K, based on the fluorescence intensity ratio of thermal-coupled levels (H-2(11/2)/S-4(3/2)). Magnetic characterization reveals that the room-temperature ferromagnetism has a saturation magnetization of 0.055 emu/g and a coercive field of 49 Oe, with a Curie temperature exceeding 300 K, which shows the potential for room-temperature spintronic applications. First-principle calculations attribute the observed ferromagnetism to Al vacancies, whose formation energy is significantly reduced by Er doping, leading to a high concentration of Al vacancies. These findings highlight the potential of AlN:Er3+ pine-shaped nanostructures in various applications, including optoelectronics, temperature sensing, and dilute magnetic semiconductors.

The intricate microstructure of conch shells endows them with high mechanical properties. However, it is challenging to integrate bionic design into engineering materials due to the microscopic visualization and complexity of the shell structure. In this study, interlayer separation was achieved by precisely removing the soft organic tissue, revealing an interface microstructure characterized by convex features and alternating orientations. Notably, this unique microstructure influences angular deflection and tangential displacement when cracks propagate across different macroscopic layers-a phenomenon not previously reported in the literature. To elucidate the energy dissipation and crack propagation mechanisms of the conch shell, quasi-static in situ indentation and in situ impact experiments were conducted. Inspired by the structural characteristics of the conch shell, a microstructure-guided 3D printing strategy was developed to fabricate a polylactic acid (PLA) skeleton. Subsequently, a silicone elastomer was injected into the PLA skeleton under high pressure and solidified, resulting in a rigid-flexible coupled bio-inspired composite with a multi-scale layered structure. The multi-level cross-layered architecture significantly alters the crack propagation path, and the impact toughness of the conch shell-inspired composite improves by 215 % compared to the 3D-printed homogeneous PLA. Furthermore, the introduction of microstructural design between layers enhanced the impact resistance of the composite by an additional 85 %. The fabrication process and structural design principles presented in this study are broadly applicable to the development of high-strength composites using a variety of material systems. STATEMENT OF SIGNIFICANCE: The exceptional mechanical performance of conch shells originates from their multiscale hierarchical architecture and unique interfacial microstructures. This study elucidates their crack-deflection mechanisms and develops an innovative bio-inspired 3D printing strategy for advanced composites. Our approach enables precise control of material heterogeneity and complex geometries, facilitating next-generation impact-resistant materials development. This research establishes a transformative paradigm for engineering lightweight, high-performance impact-resistant materials with potential applications in aerospace systems, ballistic armor, and protective gear design.

The aim of this study is to address the problems of oil mixing during the sequential transportation of refined oil and the influence of temperature on the quality detection of refined oil. To better detect the quality of refined oil, UV-Visible transmission spectroscopic experiments of 92# gasoline, diesel oil, and their mixtures at different temperatures are performed. Then, the influence of temperature on the transmission spectrum is analyzed, and the transmittance–temperature compensation equations are obtained. Based on the double-thickness inversion model, the optical constants of the mixed refined oil at UV-Visible wavelengths are obtained, and the effect of temperature on the optical constants is analyzed. For a specified optical range, the transmittance of the mixed refined oil gradually increases with increasing temperature. The temperature has a certain effect on the optical constant of the refined oil; moreover, the relationships between the transmittance of the refined oil and the change in temperature are obtained at 364, 378, and 394 nm; these wavelengths are selected based on a combination of characteristic spectra calculated by a genetic algorithm. The obtained relationship can effectively remove the influence of temperature changes on the transmittance spectra of refined oil to improve the accuracy of detection.

Due to its unique advantages including non-contact operation, high sensitivity, and exceptional spatial resolution, nanoscale optical thermometry has become an indispensable technique with widespread applications in micro/nanoelectronics, integrated photonic systems, and biomedical engineering. Here, Yb3+/Tm3+ co-doped AlN nanowires were successfully synthesized via an arc-discharge method. The nanowires, characterized by Xray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy, energy-dispersive X-ray spectroscopy, scanning electron microscopy, and transmission electron microscopy, exhibit lengths of several micrometers and uniform diameters ranging from 10 to 20 nm, yielding a high aspect ratio. Under 980 nm excitation, the nanowires display distinct up-conversion (UC) luminescence, with emission bands at 544 nm (green), 654 nm and 691 nm (red), and 795 nm (near-infrared), corresponding to Tm3+ ion transitions. The AlN:Yb3+/Tm-3+ nanowires show excellent optical thermometry performance, achieving a maximum relative sensitivity (Sr) of 3.32 % K-1 at 298 K and a temperature resolution (delta T) of 0.009 K. These results underscore the potential of AlN: Yb3+/Tm3+ nanowires for advanced optical temperature sensing in nanotechnology, biomedical applications, and high-resolution thermal imaging.

The rare-earth tritelluride GdTe3, in both bulk and flake forms, exhibits intriguing properties, including high carrier mobility, superconductivity, and charge density wave transitions. In this study, the axial and dimensional effects of the van der Waals antiferromagnet GdTe3 in the ab-plane on its cryogenic magnetic properties were systematically explored. Temperature–magnetic field phase diagrams for GdTe3 under magnetic fields aligned along the a- and b-axes (H || a and H || b) were constructed, revealing significant ab-plane anisotropy and the emergence of a novel magnetic state. Magnetization curves for H || a and H || b further confirmed this anisotropy. The magnetic susceptibility χ(T) of thin and thick samples showed distinctly different ground states under H || a. In addition, the separation of zero-field-cooled and field-cooled curves observed at 7.0 K suggests a spin density wave linked to an incipient antiferromagnetic order oriented along the c-axis. These findings demonstrate that the magnetic ground states of GdTe3 can be tuned by controlling the material’s dimensionality at cryogenic temperatures.

Highly pure amorphous SiO2 nanowires (NWs) doped with rare earth (RE) ions (e.g., Ce3+, Eu2+, Tb3+, Dy3+, and Sm2+) were prepared by plasma-assisted thermal evaporation of SiO2 powder and the corresponding RE oxides in an argon atmosphere. The synthesized doped SiO2 NWs were characterized using various techniques, such as XRD, FTIR, XPS, SEM, EDS and TEM. The doped SiO2 NWs possess amorphous properties with diameters between 50 and 200 nm and lengths up to 10 mu m. The photoluminescence properties of RE-doped SiO2 NWs were systematically studied, including excitation and emission spectra, lifetime, thermal quenching, and CIE coordinates. All doped SiO2 NWs exhibit characteristic emission lines or bands corresponding to the RE ions. Given their strong characteristic emissions and nanoscale dimensions, these doped SiO2 NWs have the potential to become an important class of nanomaterials for future integrated nanophotonic applications.

We hereby intend to further explore and confirm the underlying mechanism of Small nucleolar RNA Host Gene 1 (SNHG1) in osteoarthritis (OA). For in vitro assays, OA was induced in primary chondrocytes with interleukin-1β (IL-1β) treatment; while for in vivo tests, OA model was established in mice using the destabilization of the medial meniscus (DMM) method. Cell viability and apoptosis were assessed with MTT and flow cytometry assays, respectively. Cartilage tissue was stained by Safranin-O/Fast Green Staining. The mRNA and protein levels were separately determined via quantitative real-time polymerase chain reaction (qRT-PCR) and western blot. SNHG1 overexpression promoted the viability yet inhibited the apoptosis of chondrocytes injured by IL-1β. Moreover, the overexpression of SNHG1 promoted B-cell lymphoma-2 (Bcl-2) expression and activated phosphoinositol-3 kinase (PI3K)/protein kinase B (Akt) pathway but suppressed the process of autophagy, which led to down-regulation of light chain 3 (LC3)-II/I level and up-regulation of p62 level. However, rapamycin (RAPA, an autophagy activator) and LY294002 (a PI3K inhibitor) reversed the effects of SNHG1 overexpression on the viability and apoptosis of chondrocytes as well as on the proteins related to PI3K/Akt pathway and autophagy. In OA-modeled mice, SNHG1 overexpression prevented the loss of chondrocytes via the activation of PI3K/Akt pathway and the suppression of autophagy. SNHG1 overexpression might inhibit the apoptosis of chondrocytes by promoting PI3K/Akt pathway and inhibiting autophagy.

Epoxy resin (EP) as common polymers have attracted much attention in the field of shape memory materials due to their excellent properties. However, epoxy-based shape memory polymers suffer from a trade-off between strength, toughness, variable stiffness capability and shape memory properties, and thus are subject to significant limitations in their applications. In this paper, we propose a method to prepare epoxy composites with high strength and toughness and high shape memory properties by introducing a lot of hydrogen bonds. Hydrogen bonding is generated through polycaprolactone (PCL) induced EP phase separation. A low melting point alloy (L) was also added to enhance the shape memory properties of the composites. The synthesis mechanism of EP and the formation mechanism of hydrogen bonding were revealed. The effects of the introduction of hydrogen bonding on the mechanical properties, stiffness and shape memory properties of the composites were investigated. New ideas and design directions are provided for the optimisation of modification of high-performance shape memory epoxy resins.

Due to the characteristics of non-contact, high sensitivity and spatial resolution, nanoscale optical thermometry is necessary in many applications such as micro/nano electronics, integrated optics and biomedicine. Herein, we report the synthesis of Nd3+/Yb3+ co-doped AlN (AlN:Nd3+/Yb3+) nanorods using an arc discharge method and investigate their phase, composition and morphology using XRD, Raman, XPS, EDS, ICP, SEM and TEM. The nanorods with rectangular cross-section are highly single crystalline and have a uniform smooth surface. Upon excitation at 980 nm, AlN:Nd3+/Yb3+ nanorods exhibit up-conversion (UC) visible emission bands (around 544, 595 and 667 nm) and near-infrared emission bands (around 755 and 806 nm), which correspond to intra-4f electron transitions of the Nd3+ ions. Later, the temperature dependence of UC luminescence behavior was systemically studied using luminescence intensity ratio (LIR) technique. It was verified that LIRs with nonthermally coupled levels ((4)G(7/2)/F-4(5/2) or (4)G(7/2)/F-4(7/2)) are suitable for temperature sensing. The maximum relative sensitivity based on (4)G(7/2)/F-4(7/2) is 4.63% K-1 at 298 K, which is one of the highest values reported for optical thermometers. This work provides an efficient method for synthesizing wide-band gap semiconductors with doped size-mismatched functional atoms that can be used for high-sensitivity optical thermometry.

Shape Memory Polymers (SMPs) need to be given a temporary shape in advance to realize the shape memory process, but the manual shaping process is cumbersome and has low precision. Here, we propose a universal applicable method for 4D printing self-folding SMPs by pre-stretching extruded filaments during 3D printing, the temporary shape of the SMPs were designed and fixed during 3D printing. Prepared samples can automatically perform shape memory process under stimulation without manual temporary shape programming process. Furthermore, using carbon ink as a photothermal conversion agent enables the 4D printing SMPs to have thermal and light response characteristics. In addition, some bionic applications of self-folding SMPs were demonstrated, such as self-morphing grasper, DNA double helix structures, programmable sequential switching mimosa, self-folding box and human hand. The combination of SMP and 3D printing fully takes advantage of 4D printing technology, and the self-folding SMPs show great potential applications in the fields of tissue engineering scaffold, self-folding robots, self-assembly system and so on.

Utilizing in situ Raman spectroscopy, resistivity, and Hall-effect measurements, we conducted an extensive investigation on the continuous electronic phase transitions and transport properties of two-dimensional (2D) tellurium (Te) under high pressure at room and low temperature (80–300 K). The distinguishable decrease in the A1 Raman mode's full width at half maximum in the trigonal phase (Te-I) indicated an electronic phase transition at 2.2 GPa. The following Hall-effect experiments located the Lifshitz transition and the semiconductor-semimetal transition at 0.9 and 1.9 GPa, respectively, and the semiconductor-semimetal transition was also confirmed by resistivity variation through temperature. The charge carrier types of the Te changed from hole to electron during the phase transition from Te-I to Te-II (triclinic phase) at low temperature, while the transport parameters remained almost unchanged during the phase transition from Te-II to Te-III (monoclinic phase). The results offered complete and thorough electronic phase transitions and transport characteristics of 2D Te, hence great advancing the potential application of Te in electronic devices.

Gd3+ co-doping is effective to enhance the photoluminescence of rare earth activators in various host due to energy transfer, however, it is rarely reported via such strategy to regulate persistent luminescence properties. In this work, Gd3+ was co-doped into the SrLaAlO4: Tb persistent luminescence phosphors, and it is found that the photoluminescence and persistent luminescence of the products can be simultaneously improved. The results indicate that as the doping concentration of Gd3+ increases, the particle diameters increase which contributes the increased luminescence. Additionally, an energy transfer process from Gd3+ to Tb3+ ions was observed, which enhances the emission of Tb3+ ions. Furthermore, the persistent luminescence properties of the synthesized phosphors were improved. When the UV light source is turned off, the persistent luminescence of SrLaAlO4: 0.03Tb(3+), xGd(3+) (x = 0.00-0.97) can last for more than 2 h, which is 100 % enhanced compared to SrLaAlO4: 0.03Tb(3+). The trap distribution of SrLaAlO4: 0.03Tb(3+), xGd(3+) (x = 0.00-0.97) phosphors was analyzed by thermoluminescence. It is found that after the substitution of La3+ with Gd3+, the trap position shifted towards higher temperatures and the trap concentration increased. The initial intensity of the persistent luminescence was also enhanced after Gd3+ co-doping. Based on the experimental findings, the luminescence and persistent luminescence mechanism of SrLaAlO4: 0.03Tb(3+), xGd(3+) (x = 0.00-0.97) phosphors were described and discussed.

Rare-earth (RE) doped aluminum nitride (AlN) holds great promise for integrated optoelectronic devices. Here, the Ho and Yb co -doped AlN (AlN:Ho 3+ /Yb 3+ ) submicron towers were prepared by a direct nitridation route. XRD, Raman, XPS and EDS studies showed successful doping of Ho and Yb ions into AlN. SEM images show that the submicron towers have an interesting layered structure by layer -by -layer stacking of hexagonal AlN nanosheets. Under excitation at 980 nm, AlN:Ho 3+ /Yb 3+ submicron towers exhibit up -conversion (UC) luminescence at 540, 550, 659, and 762 nm, which are due to Ho 3+ /Yb 3+ system from 5 F 4 , 5 S 2 -> 5 I 8 , 5 F 5 -> 5 I 8 , and 5 F 4 , 5 S 2 -> 5 I 7 respectively. Based on the intensity ratio and decay lifetime of UC luminescence, the optical temperature sensing characteristics are investigated from 298 K to 548 K. The maximum relative sensitivities associated with the intensity ratio of I 540, 550 and I 659 and decay lifetime of 659 nm are as high as 2.73% K -1 and 0.43% K -1 , respectively. This work broadens the optoelectronic properties of RE doped AlN.

A series of Tb3+ substituted layered perovskite Sr(La1-xTbx)AlO4 (x = 0-1) was synthesized via solid-state reaction. The influence of Tb3+ on the phase, structure, photoluminescence, and long afterglow properties of the SrLaAlO4 product was investigated. The fully substituted product SrTbAlO4 was found to be isostructural with its SrLaAlO4 counterpart, and the crystal structure parameters were first reported in this work. Photoluminescence investigation found that benefiting from the unique layered crystal structure, the activator Tb3+ was well separated and the optimal doping concentration was found to be as high as 20 at%. Except for photoluminescence, the products simultaneously show long afterglow properties due to disorder cations distribution in the local structure and thus induced defect condition. When the UV light source is turned off, the afterglow luminescence of SrLaAlO4: 0.03 Tb3+ can last over 1 h. The trap distribution of SrLaAlO4: Tb3+ was analyzed in detail by thermoluminescence. The trap depth is calculated to be around 0.7-0.81 eV, the value of which highly coincides with the ideal energy level for trapping and releasing electrons at room temperature. On the basis of the experimental results, the mechanism of long afterglow luminescence of SrLaAlO4: Tb3+ is elaborated and discussed.