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Rare earth ions doped ferroelectric ceramics have attracted much attention because rare earth ions can effectively regulate the ferroelectric and energy storage properties of ceramics. Herein, Ba 1- x Ca x Ti 1- y Hf y O 3 ceramics modified with Ca2+ and Hf4+ are prepared, and the effects of different Ca2+ and Hf4+ concentrations on the crystal structure, microstructure and electrical properties of Ba 1- x Ca x Ti 1- y Hf y O 3 ceramics are investigated. Through the analysis on the ceramic structure and electrical properties, Ba 0.96 Ca 0.04 Ti 0.85 Hf 0.15 O 3 (BCTH) ceramic shows excellent comprehensive performance. Using BCTH ceramic as matrix material, the influences of different Pr3+ concentrations on the structure and electrical properties of the BCTH: x %Pr3+ ceramics are studied. Energy storage efficiency (η) gradually increases with the increase of Pr3+ concentration, while the energy storage density (W d) shows a trend of first increasing and then decreasing, reaching the maximum value for x = 0.6 (W d = 0.338 J/cm3, η = 87.86 %), which was higher than that of pure BCTH ceramics (W d = 0.212 J/cm3, η = 78.05 %) increased by 59.43 % and 12.57 %, respectively. All the samples show good stability of energy storage temperature and frequency. After Pr3+ doping, the Curie transition temperature of the ceramics first increas and then decreases, and show a wider transition peak, indicating that the transition from ferroelectrics to relaxation ferroelectrics occurres. The excellent electrical properties of BCTH: x %Pr3+ ceramics indicate their potential application value in the field of electricity. [ABSTRACT FROM AUTHOR]

Rare earth doped ferroelectric ceramics have attracted much attention due to their great potential application for novel multifunctional optical-electro devices. Herein, the x % mol Sm3+ doped BaTiO 3 (BTO: x Sm3+) ceramics were fabricated by the conventional solid-state reaction method. The Sm3+ ions composition dependent phase structure, ferroelectric, energy storage and photoluminescence properties were systematically investigated. With the increase of Sm3+ ions composition, the remanent polarization decreases dramatically from 15.705 μC/cm2 (BTO) to 7.132 μC/cm2 (BTO:3.0%Sm3+), but the energy storage density and efficiency increase greatly with a relative change of 79.76% and 31.13%, respectively. Furthermore, Sm3+ doping causes the transformation from the tetragonal to pseudo-cubic phase for BTO ceramics at room temperature, resulting in a broader temperature transition range from the ferroelectric to paraelectric phase and a lower Curie temperature. Particularly, the pure BTO and BTO: x Sm3+ ceramics show great thermal stability for energy storage properties. In addition, under the excitation of 408 nm near-ultraviolet light, the BTO: x Sm3+ ceramics exhibit the strongest orange-red emission peak around 596 nm with a large relative tunability of intensity by 88.97%. The results suggest that the BTO: x Sm3+ ceramics are suitable for the design of optoelectronic devices. [ABSTRACT FROM AUTHOR]

As it remains unclear whether there are sex-based differences in clinical outcomes after thoracic endovascular aortic repair (TEVAR), this meta-analysis aimed to evaluate differences in early outcomes and overall survival between female and male patients who underwent TEVAR. The PubMed, Embase, Web of Science, and Cochrane Central databases were searched for eligible studies published through June 10, 2023, that reported sex-based differences in clinical outcomes after TEVAR. The primary outcome was operative mortality; second outcomes included stroke, spinal cord ischemia, acute kidney injury, hospital length of stay, and overall survival. Patient characteristics, operative data, and early outcomes were aggregated using the random-effects model, presenting pooled risk ratio (RR) or standardized mean difference along with their corresponding 95% confidence intervals (CIs). Overall survival was assessed by reconstructing individual patient data to generate sex-specific pooled Kaplan-Meier curves. This study was registered in PROSPERO (CRD42023426069). Of the 1785 studies retrieved, 14 studies met all eligibility criteria, encompassing a total of 17,374 patients, comprising 5026 female and 12,348 male patients. Female patients were older, had a smaller maximum aortic diameter, had lower rates of smoking and coronary artery disease, and had higher rates of anemia. Intraoperatively, female patients were more likely to use iliac conduits and require blood transfusions. There were no sex-based differences in operative mortality (RR: 1.12, 95% CI: 0.90-1.40; P =.309), stroke (RR: 1.14, 95% CI: 0.95-1.38; P =.165), spinal cord ischemia (RR: 1.33, 95% CI: 0.83-2.14; P =.234), acute kidney injury (RR: 0.78, 95% CI: 0.52-1.17; P =.228), and hospital length of stay (standardized mean difference: 0.09, 95% CI: −0.03 to 0.20; P =.141). Pooled Kaplan-Meier estimates showed a worse overall survival in female patients compared with male patients (87.2% vs 89.8% at 2 years, log-rank P =.001). Among patients treated by TEVAR, female sex was not associated with increased risk of operative mortality or major morbidity. However, female patients exhibited a lower overall survival after TEVAR compared with male patients. [ABSTRACT FROM AUTHOR]

The development of low-cost and high-safety cathode materials is critically important to sodium-ion battery (Na-ion) research. Here we report a carbon nanotube (CNT)-percolating Na 2 Fe(SO 4) 2 cathode (NFS-CNT) prepared via a rationally designed mechano-chemical method. The material synthesis mechanism is elucidated for the first time by in situ X-ray diffraction and thermogravimetric analysis. It is discovered that Na 2 Fe(SO 4)·4H 2 O is formed as an intermediate phase during the mechano-chemical process, which is dehydrated to produce the Na 2 Fe(SO 4) 2 cathode material upon a mild thermal treatment. The NFS-CNT composite cathode achieves an ultra-long cycle-life of over 13,000 cycles at 10 C at room temperature and over 6000 cycles at 55 °C, demonstrating its exceptional durability. The superior cycling performance is attributed to the small lattice change during Na-ion extraction/insertion and the percolating CNT network. Furthermore, the NFS/CNT cathode exhibits stable cycle performance in Na-ion full cells (93.4 % retention after 700 cycles) and a significantly lower heat release (∼ 229.2 J g−1) at the fully charged state compared to a wide range of Na-ion and Li-ion cathodes. materials. demonstrating its high thermal stability and safety. This work provides a promising path towards developing low-cost, high-performance Na-ion batteries. [Display omitted] • A long-cycle-life and high-safety Na-ion battery cathode is developed. • The material synthesis mechanism is revealed by in situ techniques. • The percolating carbon nanotubes greatly enhance the electrochemical performance. • Na-ion full batteries are assembled to demonstrate practical relevancy. [ABSTRACT FROM AUTHOR]

High-entropy layered oxide (HEO) cathodes have become a focal point of research in sodium-ion batteries. Herein, we identify two guidelines that are vital for the design and fabrication of HEO O3-type cathodes: enhanced energy storage capacity and robust cathode architecture. To achieve these benchmarks, precise methods are required to adjust the energy levels of the transition metals and maintain ionic radius discrepancies within 15%. We have synthesized and examined various HEO O3-type cathode composites. Specifically, the O3-Na[FeCoNiTi] 1/6 Mn 1/4 Zn 1/12 O 2 (O3-FCNTMZ 1/12) has demonstrated an impressive reversible capacity of 127.3 mAh g−1, with exceptional long-cycle stability and superb rate capabilities. Notably, the O3-FCNTMZ 1/12 cathode exhibits superior Na storage performance at low temperatures. At −20 °C, it maintains 109.6 and 91.1 mAh g−1 at 0.1 and 1 C, respectively, with an impressive 88% capacity retention after 1000 cycles at 1 C. In situ X-ray diffraction analysis reveals a subtle phase transition from O3 to P3, with only a 3% volume expansion. Moreover, ex situ X-ray absorption spectroscopy confirms minimal fluctuation in the TM-O and TM-TM distances, remaining under 9.9%. These well-defined criteria offer a clear strategy for designing and developing the O3-FCNTMZ 1/12 cathode, facilitating high-performance sodium-ion batteries, especially for demanding low-temperature applications. [Display omitted] • Designing O3-type cathode should abide two key criteria: enhanced energy storage capacity and robust cathode architecture. • The schematic diagrams of different energy levels and ionic radius discrepancies of transition metal are established. • The O3-Na[FeCoNiTi] 1/6 Mn 1/4 Zn 1/12 O 2 delivers 127.3 mAh g−1 capacity, with exceptional cycling stability and rate capability. • The O3-Na[FeCoNiTi] 1/6 Mn 1/4 Zn 1/12 O 2 cathode maintains 80.1 mAh g−1 capacity after 1000 cycles at 1C under −20 °C. [ABSTRACT FROM AUTHOR]

• A comprehensive assessment model for radiant thermal damage has been developed. • Lead glass is the most prone to suffer softening damage. • Whether glass can be softened depends on its surface temperature. • The thermal insulation effect of the double-pane glass is superior. In a strong explosion, the propagation velocity of thermal radiation is much higher than that of the shock wave. The thermal damage caused by thermal radiation and the destruction generated by the shock wave are equally significant for the target, but there is little research on the former. The thermal effect assessment model established in this study simultaneously considers two crucial factors: heat flux and duration, making it more scientific and comprehensive compared to existing models that rely solely on heat flux or heat metering as a single standard to assess thermal effects. When the temperature of 5000 K lasts for 3 s, the surface of single-pane quartz glass has a 0.73 mm softening failure. The quartz glass with a thickness of 10 mm is fully softened when the 5000 K temperature lasts for 107 s. When the fire temperature of 3500 K lasts for 1000s, the softening range of quartz glass is 5.28 mm. The quartz glass with a thickness of 10 mm has a softening range of 0.14 mm when the temperature of 3500 K lasts for 3 s. The softening range increases to 257% (0.36 mm), 400% (0.56 mm), 521% (0.73 mm), and 629% (0.88 mm) when the temperature increases to 4000 K, 4500 K, 5000 K, and 5500 K, respectively. Whether glass can be softened depends on its surface temperature. The critical temperature for quartz glass surface softening is 3269 K, while the complete softening of 10 mm thick quartz glass occurs at 3743 K. The quartz glass with a thickness of 10 mm has a softening range of 0.38 mm when the temperature of 5000 K lasts for 1 s. The softening range increases to 150% (0.57 mm), 192% (0.73 mm), and 226% (0.86 mm) as the duration increases to 2 s, 3 s, and 4 s, respectively. Lead glass is the most prone to suffer softening damage, followed by aluminosilicate glass and quartz glass. The quartz glass has a softening range of 0.73 mm when the temperature of 5000 K lasts for 3 s. The softening range rises to 221% (1.62 mm) for aluminosilicate glass and 319% (2.33 mm) for lead glass, respectively. For aluminosilicate double-pane glass, at 5000 K for 3 s, only the glass pane near the high-temperature source has a softening failure in the range of 1.62 mm. This work reveals the physical process and microscopic mechanism of glass damage under thermal radiation. It provides the scientific basis for glass safety assessment under high temperatures. [ABSTRACT FROM AUTHOR]

In response to the intricate marine environment and the need for diverse, intelligent, and large-scale operations, clustered Autonomous Underwater Vehicles (AUVs) have emerged as a pivotal trend in AUV oceanic applications. This paper delves into three key aspects of clustered AUV control: optimal formation assembly, dynamic cooperative control, and autonomous obstacle avoidance. The formation assembly is approached as a target point allocation problem, employing an F-Norm and Dubins Path (FNDP) based method for efficient path planning and optimal allocation. A novel hybrid control strategy, LFVS, combines leader–follower (LF) and virtual structure (VS) approaches, facilitating cohesive formation maintenance with minimal communication. Additionally, the paper introduces an intelligent adaptive artificial potential field (IA2PF) method. This technique, enhancing energy efficiency and obstacle avoidance, dynamically adjusts to current conditions, thereby overcoming limitations of traditional APF methods like unreachable targets , oscillation, and dead zones. The efficacy and applicability of these methods are corroborated through extensive simulations and practical experiments using three 260 AUVs, and compared with formation control based on the LF strategy, proving their utility and stability in real-world formation assembly and maintenance tasks. • This study developed LFVS-IA2PF, a new multi-AUV formation control strategy. • FNDP is introduced for effective target point allocation in AUV operations. • This paper proposed an adaptive algorithm for AUV formation and obstacle avoidance. • The proposed algorithms are validated with both simulations and actual experiments. [ABSTRACT FROM AUTHOR]