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Currently, enhancing the output power of rotational‐mode triboelectric nanogenerators (TENGs) using various complicated systems is a contentious issue; however, this is a challenging process owing to the inherent characteristics of TENGs, namely, low output currents as opposed to high voltages. Thus, this study proposes a simple and innovative strategy for ultra‐high output peak power generation of TENGs called a self‐boosted rotational electrostatic‐discharge TENG (SRE‐TENG). The SRE‐TENG mechanism is unique as it is based on charge control and boosted discharge design, thereby achieving a remarkable peak power of 1103.8 W, peak power density of 140.6 Kw m−2, low optimum resistance of 100 Ω, and broad peak power generation range of 10 Ω to 1 GΩ. Diligent measurements and analyses of the peak and root‐mean‐square voltage and current outputs of the SRE‐TENG are conducted for various design variables and circuit configurations. The proposed SRE‐TENG mechanism is validated using experimental and multiphysics simulation results. The high‐output performance of the SRE‐TENG is demonstrated via the lighting of 3,000 LEDs and a 60‐W lamp array, continuous driving of a commercial sensor array, and hydrogen/oxygen generation via water electrolysis. [ABSTRACT FROM AUTHOR]

In this study, the physical properties of garlic just before collection were investigated, and garlic-collecting conditions are presented as basic data of design factors that can be utilized during the development of garlic collectors. The physical properties were subdivided into geometrical properties and mechanical properties, and the ecotype of garlic was divided into CSG (cold-season garlic) and WSG (warm-season garlic). Geometrical properties were compared between CSG and WSG by measuring the average weight, length, width, number of kernels, volume, and density of each cultivar, and WSG showed higher geometrical properties in all geometrical properties. In addition, there was garlic on the incomplete side of WSG, and shape non-uniformity was higher than that of CSG. There was no significant difference in the average Poisson's ratio of mechanical properties. In the case of the modulus of elasticity, Namdo cultivars showed the lowest value at 15.52 MPa. The average allowable compressive stress measured using Hooke's law was the lowest in the Uiseong cultivar (204.33 kPa) and the highest in the Danyang cultivar (376.42 kPa). The static friction coefficients among the four different materials by cultivar exhibited a commonality of being highest in aluminum and generally lowest in plastic. It is expected that the design of the garlic collector will be carried out in consideration of garlic when developing it using up-to-date physical properties of garlic just before collection. [ABSTRACT FROM AUTHOR]

Recently, as fossil fuel reserves have decreased and energy requirements have increased worldwide, wind energy, which has various advantages, such as ubiquitous, sustainable, clean, and infinite energy capacitance, has attracted increasing attention. In particular, wind‐driven fluttering‐type triboelectric nanogenerators (TENGs), which can utilize mechanical movement induced by wind energy based on the coupling of the triboelectric effect and electrostatic induction, have been widely studied. However, previous studies have not discussed structural device designs to harvest bidirectional wind energy. Herein, a wind‐driven bidirectional fluttering triboelectric nanogenerator (WBF‐TENG) is reported, which has a dual flagpole and slot structure design to generate electrical output against wind blowing from both directions. Considering natural wind flow in random direction, WBF‐TENG is more effective compared with the previous unidirectional fluttering TENGs. The electrical output of the WBF‐TENG is quantitatively measured and analyzed in terms of the peak and root mean square outputs depending on various design parameters and wind velocities. The findings demonstrated that the WBF‐TENG can be utilized as a swing safety light by continuously turning on 76 LEDs when riding a swing during right and left direction movements. Furthermore, the WBF‐TENG can scavenge omnidirectional wind energy by vertically stacking two devices. [ABSTRACT FROM AUTHOR]

This paper introduces a new fibrous system for synergistic cancer therapy, which consists of gold nanocage (AuNC)-loaded poly(ε-caprolactone) (PCL) fibers with encapsulation of a chemotherapeutic anticancer drug in their core and loading of a phase-changeable fatty acid in their sheath. Under on–off switching of near-infrared (NIR) light irradiation, the excellent photothermal ability and photostability of AuNCs allows repeated, significant heating of the fibers to a temperature available to hyperthermia. Simultaneously, the NIR light-induced heat generation enables the melting out of the loaded fatty acid, leading to a rapid release of the drug molecules from the fibers. The combination of this NIR light-triggered drug release with the repeated hyperthermia treatment exhibits excellent anticancer efficacy. [ABSTRACT FROM AUTHOR]