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Because of high voltage resistance and high-power density, traditional ceramic dielectrics have found extensive use in electronic and pulsed power systems. Nevertheless, their subpar energy storage capabilities pose a challenge in meeting the demands of integrated and lightweight power electronic devices. This paper employs compositional design to incorporate a Bi(Zn0.5Hf0.5)O3 (BZH) relaxation component, aiming to enhance the electrical breakdown strength or effective dielectric constant, ultimately increasing the energy storage density. The 0.90(Ba0.8Sr0.2)TiO3–0.10Bi(Zn1/2Hf1/2)O3 ceramics processed by the conventional solid-phase reaction method demonstrate a significant recoverable energy density of 4.20 J cm−3, an exceptional energy storage efficiency of 95.5%, with a 450 kV cm−1 high breakdown strength and impressive charge/discharge performance. This investigation presents a novel framework for enhancing energy storage performance in other material systems. [ABSTRACT FROM AUTHOR]

Lead-free ceramics are important in the sustainable advancement of energy storage techniques owing to their exceptional density of power, commendable resistance to high temperatures, and non-toxic nature. However, lead-free ceramics are no longer aligned with the requirements for the miniaturization and light weighting of electronic components because of their limited energy density and conversion efficiency. In this study, the storage performance of lead-free ceramics was optimized by constructing (1 − x)(Ba0.8Sr0.2)TiO3–xBi(Zn2/3Ta1/3)O3 ceramics using a cooperative optimization strategy. This strategy involved utilizing Bi(Zn2/3Ta1/3)O3 to induce polar nano-regions, contributing to an increase in Eb and a reduction in Pr, thereby enhancing the energy storage properties. Notably, the 0.91(Ba0.8Sr0.2)TiO3–0.09Bi(Zn2/3Ta1/3)O3 relaxation ferroelectric ceramic demonstrated the ability to simultaneously achieve an ultra-high Wrec of 5.53 J cm−3 and an excellent η of 93.6% at a relatively high electric field intensity of 460 kV cm−1. Furthermore, the samples exhibited a high η (∼96%) in the 5–100 Hz frequency range and in the 30–100 °C temperature range. The collective outstanding performance of the 0.91(Ba0.8Sr0.2)TiO3–0.09Bi(Zn2/3Ta1/3)O3 ceramic substantiates its immense potential for utilization in pulse power capacitors. [ABSTRACT FROM AUTHOR]

Bismuth‐layered ferroelectric materials with Aurivillius structure are the potential materials for high‐temperature ferroelectric materials because of their high Curie temperature and excellent ferroelectric fatigue resistance. Herein, the Aurivillius phase relaxation ferroelectrics as Ban−3Bi4TinO3n+3 (n = 4–7) ceramics are studied. The layered structures are controlled by adjusting the number of BO6 octahedrons and (Bi2O2)2+ layers. The dielectric temperature stability and voltage resistance of bismuth barium titanate ceramics are improved. The influence of composition and microstructure on their electrical properties is explored. The relationship between dielectric properties and storage properties of bismuth barium titanate ceramics and the number of layers is obtained. Ba2Bi4Ti5O18 ceramics show the best performance with an energy storage density of up to 1.16 J cm−3 and a high efficiency of ≈87.2% (under 250 kV cm−1). This work provides key materials and technologies for the next generation of energy storage capacitors that can be applied in high‐temperature environments as well as a new reference for the development of dielectric materials and the functional optimization of other Aurivillius phase ceramic materials. [ABSTRACT FROM AUTHOR]

Two new triucallane triterpenoids, polystanin F (1) and polystanin G (2), along with eight known compounds (3-10) were isolated from the fruits of Aphanamixis polystachya. Their structures were established on the basis of extensive spectroscopic analysis. Moreover, eight compounds were evaluated for their in vitro cytotoxicity against three cancer cell lines (liver cancer RT112, colon cancer HCT-116 and breast cancer M231) using the MTT method. Compound 7 showed significant cytotoxic activity against HCT-116 with IC50 1.27 μM. [ABSTRACT FROM AUTHOR]

Two new sesquiterpenoids, including a kessane-type sesquiterpenoid (1) and one bisabolane derivative (2), together with fourteen known sesquiterpenoids (3–16), were isolated from the roots and rhizomes of Valeriana amurensis. The structures of new compounds were established on the basis of extensive spectroscopic analysis. All isolates were evaluated for their effects on nerve growth factor (NGF)-mediated neurite outgrowth in pheochromocytoma (PC12) cells. As a results, four compounds including 10–12 and 15 showed potent promoting effects at the concentration of 10 µM on NGF-induced neurite outgrowth in PC12 cells with the differentiation rate of 11.84%, 12.21%, 13.77% and 12.16%, respectively. [ABSTRACT FROM AUTHOR]