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91.
Thanh Hai Nguyen Phan Khanh Linh Tran Van An Dinh Duy Thanh Tran Nam Hoon Kim Joong Hee Lee 《Advanced functional materials》2023,33(7):2210101
Development of multifunctional electrocatalysts with high efficiency and stability is of great interest in recent energy conversion technologies. Herein, a novel heteroelectrocatalyst of molecular iron complex (FeMC)-carbide MXene (Mo2TiC2Tx) uniformly embedded in a 3D graphene-based hierarchical network (GrH) is rationally designed. The coexistence of FeMC and MXene with their unique interactions triggers optimum electronic properties, rich multiple active sites, and favorite free adsorption energy for excellent trifunctional catalytic activities. Meanwhile, the highly porous GrH effectively promotes a multichannel architecture for charge transfer and gas/ion diffusion to improve stability. Therefore, the FeMC–MXene/GrH results in superb performances towards oxygen reduction reaction (ORR), oxygen evolution reaction (OER), and hydrogen evolution reaction (HER) in alkaline medium. The practical tests indicate that Zn/Al–air batteries derived from FeMC–MXene/GrH cathodic electrodes produce high power densities of 165.6 and 172.7 mW cm−2, respectively. Impressively, the liquid-state Zn–air battery delivers excellent cycling stability of over 1100 h. In addition, the alkaline water electrolyzer induces a low cell voltage of 1.55 V at 10 mA cm−2 and 1.86 V at 0.4 A cm−2 in 30 wt.% KOH at 80 °C, surpassing recent reports. The achievements suggest an exciting multifunctional electrocatalyst for electrochemical energy applications. 相似文献
92.
Jangwon Moon Junwoo Kim Hoon Lee Youngjin Moon Yongsu Lee Youngjo Bang Kyungyeol Sohn Jungsook Bae Kwangseon Kim Seungjae Bahng Heesoo Lee 《ETRI Journal》2023,45(5):781-794
Uncrewed aerial vehicles (UAVs) have become a vital element in nonterrestrial networks, especially with respect to 5G communication systems and beyond. The use of UAVs in support of 4G/5G base station (uncrewed aerial vehicle base station [UAV-BS]) has proven to be a practical solution for extending cellular network services to areas where conventional infrastructures are unavailable. In this study, we introduce a UAV-BS system that utilizes a high-capacity wireless backhaul operating in millimeter-wave frequency bands. This system can achieve a maximum throughput of 1.3 Gbps while delivering data at a rate of 300 Mbps, even at distances of 10 km. We also present the details of our testbed implementation alongside the performance results obtained from field tests. 相似文献
93.
A Novel and Facile Route to Synthesize Atomic‐Layered MoS2 Film for Large‐Area Electronics 下载免费PDF全文
Stephen Boandoh Soo Ho Choi Ji‐Hoon Park So Young Park Seungho Bang Mun Seok Jeong Joo Song Lee Hyeong Jin Kim Woochul Yang Jae‐Young Choi Soo Min Kim Ki Kang Kim 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(39)
High‐quality and large‐area molybdenum disulfide (MoS2) thin film is highly desirable for applications in large‐area electronics. However, there remains a challenge in attaining MoS2 film of reasonable crystallinity due to the absence of appropriate choice and control of precursors, as well as choice of suitable growth substrates. Herein, a novel and facile route is reported for synthesizing few‐layered MoS2 film with new precursors via chemical vapor deposition. Prior to growth, an aqueous solution of sodium molybdate as the molybdenum precursor is spun onto the growth substrate and dimethyl disulfide as the liquid sulfur precursor is supplied with a bubbling system during growth. To supplement the limiting effect of Mo (sodium molybdate), a supplementary Mo is supplied by dissolving molybdenum hexacarbonyl (Mo(CO)6) in the liquid sulfur precursor delivered by the bubbler. By precisely controlling the amounts of precursors and hydrogen flow, full coverage of MoS2 film is readily achievable in 20 min. Large‐area MoS2 field effect transistors (FETs) fabricated with a conventional photolithography have a carrier mobility as high as 18.9 cm2 V?1 s?1, which is the highest reported for bottom‐gated MoS2‐FETs fabricated via photolithography with an on/off ratio of ≈105 at room temperature. 相似文献
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High‐Performance Integrated Perovskite and Organic Solar Cells with Enhanced Fill Factors and Near‐Infrared Harvesting 下载免费PDF全文
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Hyunsik Choi Bolam Kim Sang Hoon Jeong Tae Yeon Kim Dong-Pyo Kim You-Kwan Oh Sei Kwang Hahn 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(1):2204617
A variety of wound healing platforms have been proposed to alleviate the hypoxic condition and/or to modulate the immune responses for the treatment of chronic wounds in diabetes. However, these platforms with the passive diffusion of therapeutic agents through the blood clot result in the relatively low delivery efficiency into the deep wound site. Here, a microalgae-based biohybrid microrobot for accelerated diabetic wound healing is developed. The biohybrid microrobot autonomously moves at velocity of 33.3 µm s−1 and generates oxygen for the alleviation of hypoxic condition. In addition, the microrobot efficiently bound with inflammatory chemokines of interleukin-8 (IL-8) and monocyte chemoattractant protein-1 (MCP-1) for modulating the immune responses. The enhanced penetration of microrobot is corroborated by measuring fibrin clots in biomimetic wound using microfluidic devices and the enhanced retention of microrobot is confirmed in the real wounded mouse skin tissue. After deposition on the chronic wound in diabetic mice without wound dressing, the wounds treated with microrobots are completely healed after 9 days with the significant decrease of inflammatory cytokines below 31% of the control level and the upregulated angiogenesis above 20 times of CD31+ cells. These results confirm the feasibility of microrobots as a next-generation platform for diabetic wound healing. 相似文献
99.
The circular-harmonic-function correlation filter originally proposed by Hsu and Arsenault [Appl. Opt. 21, 4016 (1982)] for in-plane rotation invariance uses only one harmonic, which results in poor discrimination capability of the filter. Various methods to use multiple harmonics were explored previously by different researchers. We present a new method to combine multiple circular harmonics into a single filter that can provide the desired correlation response to in-plane rotation while minimizing the correlation-plane energy. Since multiple harmonics are included, the filter can discriminate well, and since correlation-plane energy is minimized, correlation peaks tend to be sharp. Since the designer can specify the desired in-plane rotation response, a variety of filter behaviors (including complete invariance to input rotations) can be obtained. Underlying theory is discussed, and simulation results are presented. 相似文献
100.
We study online scheduling on two unbounded parallel-batching machines with limited restarts to minimize the makespan. In this system jobs arrive over time and a batch can be restarted if and only if all the jobs in it have never been restarted. To tackle this difficult problem, we make the second-restart assumption whereby we can only interrupt a running batch B at time t if both machines are busy at time t and batch B has a later starting time than the other running batch. For this case, we provide a best online algorithm with a competitive ratio . For the general problem, we show that no online algorithms can have a competitive ratio less than 1.298, leaving a gap from 1.298 to 1.366. 相似文献