Daegu Gyeongbuk Institute of Science and Technology
DGIST Library Institutional RepositoryNot a member yet
12664 research outputs found
Sort by
In-situ coating of metal fluoride/polymer bi-layer protection for dendrite-free, anti-corrosive Zn-metal anode
No full textTo pursue a highly safe, sustainable energy storage system, aqueous Zn metal batteries (AZBs) have emerged due to their great promises of non-flammability and cost-effective energy storage. However, the growth of Zn dendrites and the parasitic hydrogen evolution reaction (HER) in Zn metal anodes (ZMAs) have resulted in the failure of AZBs to meet commercial requirements. This study presents bi-layer-structured ZMA protection via a one-step coating of a hydrophilic polymeric outer layer and a zincophilic Ag-decorated inner layer (Ag0/ZnF2) through an in-situ displacement reaction by a silver fluoride (AgF) additive to synergistically suppress Zn dendrites and the HER. The AgF-guided bi-layered Zn protective layer (BSPL@Zn) plays a synergistic role in suppressing HER and ZMA corrosion but facilitating uniform Zn deposition, largely extending the short-circuiting time with a three-fold reduction in H2 gas evolution. BSPL@Zn demonstrates a robust Zn||Zn cell cycling over 1800 h at 5 mAh cm−2 of Zn plating capacity. The Zn||NH4V4O10 cell with BSPL@Zn exhibited stable cycling over 1000 cycles with 80% capacity retention. Crafting a bi-layered protection framework with an optimal material selection could offer a promising pathway for deploying ZMA in AZBs. © 2024 Elsevier B.V.FALSEsciescopu
Tunneling Transistor with a Stacked Floating Electrode for Current Saturation
No full textWe demonstrated a tunneling transistor with a stacked floating electrode structure. Tunneling transistors suffer from a poor gate modulation property with large gate leakage current, absence of current saturation, and lithography limitations for a small tunneling gap. In this work, a floating electrode stacked vertically on source/drain electrodes was suggested to overcome these issues. The electric potential of the floating electrode was controlled by the side dual gate structure. Because of the vertical electron movement through the floating structure, ultra-small tunneling distance (~20 Å) can be easily obtained without a complicated lithography process. The operating voltage is thereby small (<2 V) due to the thin tunneling barrier. The transistor also has a very low leakage current of ~10 pA due to the absence of electrode overlap. The gate modulation property was improved by controlling the potential energy level of the floating electrode. Additionally, the current saturation results were considerably enhanced. The average standard deviation is 15 nA/cm2 at the saturation region. IEEEFALSEsciescopu
Kink-Controlled Gold Nanoparticles for Electrochemical Glucose Oxidation
No full textEnzymes in nature efficiently catalyze chiral organic molecules by elaborately tuning the geometrical arrangement of atoms in the active site. However, enantioselective oxidation of organic molecules by heterogeneous electrocatalysts is challenging because of the difficulty in controlling the asymmetric structures of the active sites on the electrodes. Here, we show that the distribution of chiral kink atoms on high-index facets can be precisely manipulated even on single gold nanoparticles; and this enabled stereoselective oxidation of hydroxyl groups on various sugar molecules. We characterized the crystallographic orientation and the density of kink atoms and investigated their specific interactions with the glucose molecule due to the geometrical structure and surface electrostatic potential. © 2024 American Chemical SocietyFALSEsciescopu
Electronic Parking Brake
No full text본 발명의 일 실시예에 따른 전자식 주차 브레이크는, 자동차의 휠과 함께 회전하는 디스크에 대하여 전진 및 후진가능한 패드, 하나의 모터를 포함하여 인가되는 전류에 의해 제1 방향 회전력 및 제2 방향 회전력을 제공하는 동력부, 서로 교차하는 축을 갖고 제1 기어비를 형성하는 제1 원동기어 및 제1 피동기어를 포함하고, 상기 동력부와 연결되어 상기 제1 방향 회전력에 의해 구동가능한 제1 기어부, 및 서로 교차하는 축을 갖고 제2 기어비를 형성하는 제2 원동기어 및 제2 피동기어를 포함하고, 상기 동력부와 연결되어 상기 제2 방향 회전력에 의해 구동가능한 제2 기어부를 포함하고, 상기 패드는, 상기 제1 기어부의 구동에 의해 상기 디스크에 대하여 전진하고, 상기 제2 기어부의 구동에 의해 상기 디스크에 대하여 후진할 수 있다
Electronic Parking Brake
No full text본 발명의 일 실시예에 따른 전자식 주차 브레이크는, 자동차의 휠과 함께 회전하는 디스크에 대하여 전진 및 후진가능한 패드, 인가되는 전류에 의해 제1 방향 회전력 및 제2 방향 회전력을 제공하는 동력부, 제1 기어비를 갖고, 상기 동력부와 연결되어 상기 제1 방향 회전력에 의해 구동가능한 제1 기어부, 및 제2 기어비를 갖고, 상기 동력부와 연결되어 상기 제2 방향 회전력에 의해 구동가능한 제2 기어부를 포함하고, 상기 패드는, 상기 제1 기어부의 구동에 의해 상기 디스크에 대하여 전진하고, 상기 제2 기어부의 구동에 의해 상기 디스크에 대하여 후진할 수 있다
Animal-free scaffold from brown algae provides a three-dimensional cell growth and differentiation environment for steak-like cultivated meat
Get PDFScaffolds for the production of cultivated meat, a promising sustainable meat alternative, should exhibit physical and chemical properties that enable three-dimensional animal cell culture, along with biological characteristics that support cell attachment, proliferation, and differentiation. Additionally, the scaffold should be crafted from edible materials and offer textural similarities to meat and have minimal influence on flavor and taste. Herein, an edible alginate-based alginate-cellulose hydrogel (ACe-gel) scaffold derived from the brown alga Undaria pinnatifida is developed. In terms of physical characteristics, the scaffold had porosity (119.5 ± 37.2 μm) and moisture-holding capacity (73.03 ± 3.82, 68.66 ± 9.54, and 84.17 ± 9.94 at 25 °C, 37 °C, and 60 °C, respectively) suitable for three-dimensional culture and differentiation of bovine muscle stem cells (bMuSCs). Accordingly, the scaffold was superior to a commercial alginate scaffold in terms of the attachment and proliferation of bMuSCs (5.5-fold over 72 h), and its performance was comparable with that of a lyophilized collagen scaffold (7.8-fold over 72 h, compared with the pure alginate). The bMuSCs cultured on the ACe-gel scaffold were capable of differentiating into muscle fibers, as verified by gene expression profile analysis. Furthermore, the scaffold exhibited minimal heavy metal contents and distinct seaweed odorants, while the stress-strain characteristics of the scaffold cultured with bMuSC (Young's modulus of raw ACe-gel: 285.19 ± 83.37 kPa, cooked ACe-gel meat: 880.60 ± 485.60 kPa) closely resembled that of meat (raw beef: 267.76 ± 156.42 kPa, cooked beef: 1331.94 ± 762.43 kPa). These findings highlight that the seaweed-derived and animal-free ACe-gel scaffold has strong potential for utilization as a food technology for cultured meat production in the future. © 2024 The AuthorsTRUEsciescopu
Recent advances in the hybrid cathode for rechargeable zinc-bromine redox batteries
No full textRechargeable metal-bromine batteries have emerged as promising candidates to develop competitive, cost-effective, high-energy-density energy storage systems. The general configuration of a metal-bromine battery includes a metal anode and a bromine cathode. The emergence of zinc-bromine redox batteries (ZBRBs) is attributed to the earth's abundance of zinc, the cost-effectiveness of the active materials, and the high theoretical energy density. Recent advancements have highlighted using bromides (Br−, Br2, and Brn− (n = 3, 5, 7 …)) entrapping materials for the cathode to enhance the Br−/Br2 redox reaction and inhibit the Br2 diffusion in the ZBRBs. This review aims to explore the various arrangements and insights into bromides-entrapping-based cathodes recently reported. Finally, we share perspectives on the remaining challenges and prospects for the ZBRBs. © 2024 Elsevier B.V.FALSEsciescopu
ELECTRONIC DEVICE THAT DISPLAY A PLURALITY OF VIRTUAL SENSOR POSITION FOR COMPUTER MOUSE AND METHOD FOR OPERATION THEREOF
No full textA Two-Chamber Soft Actuator With An Expansion Limit Line for Force Enhancement
No full textSoft pneumatic actuators (SPAs) that can perform three-dimensional movements are being developed to perform more diverse tasks beyond simple bending. The conventional PneuNet actuators have expansion limit layers, which can obtain more tip force by limiting the expansion of the bottom. However, the presence of the expansion limit layer impedes other motions, such as rotation, when configured with multiple channels. In this study, we propose a two-chamber PneuNet actuator (TPA) to which the expansion limit line (ELLINE) is applied to obtain a force gain without a limitation on rotational motion due to the expansion limit layer. We perform a finite element analysis (FEA) on three designs that can rotate and bend using twochamber to find the optimal design. The effects on twisting, bending, and tip force according to the width of the ELLINE on the selected design were then verified through an FEA. After measuring rotation and bending for the fabricated actuator with and without the ELLINE. In the case of the fabricated TPA with the ELLINE, the bending decreased by 19.8%. However, rotation increased by 22.8 %, tip force increased by 1.53 times (with the ELLINE the force is 2.77 N in 70 kPa; without the ELLINE it is 1.8 N in 70 kPa), and grasping force increased by 5 times (with the ELLINE the force is 500 gf in 70 kPa, without the ELLINE it is 100 gf in 70 kPa). Furthermore, we fabricated a gripper using three actuators, capable of holding a weight of 505 g and objects of various shapes.FALSEsciescopu