Article
Nanoscience & Nanotechnology
Md Redwanul Islam, Georg Schoenweger, Niklas Wolff, Adrian Petraru, Hermann Kohlstedt, Simon Fichtner, Lorenz Kienle
Summary: In this study, the structural and electrical properties of Al0.72Sc0.28N thin films grown on different substrates were compared. It was found that using an epitaxial Pt electrode layer on a GaN/Al2O3 substrate significantly improved the leakage current and coercive field of the material. Furthermore, an all-epitaxial Al0.72Sc0.28N/Pt/GaN stack with a sharp interface thickness of less than 1 nm was demonstrated.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Physical
Marek Vidis, Ihor O. Shpetnyi, Tomas Roch, Leonid Satrapinskyy, Michal Patrnciak, Andrej Plecenik, Tomas Plecenik
Summary: A flexible hydrogen gas sensor with a Pt/TiO2/Pt electrode structure exhibited good response to hydrogen at room temperature and performed well under different concentrations and temperatures. Additionally, the sensor showed slight improvement in performance after being bent multiple times.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Computer Science, Artificial Intelligence
Di Zhang, Junqing Le, Xinyu Lei, Tao Xiang, Xiaofeng Liao
Summary: This paper reviews the development and application of blockchain technology, focusing on the redaction mechanisms of mutable blockchains. It discusses the challenges and evaluation criteria of redaction mechanisms, conducts a comprehensive evaluation and analysis of existing redaction mechanisms, providing insights for the design of future mutable blockchains.
INTERNATIONAL JOURNAL OF INTELLIGENT SYSTEMS
(2021)
Article
Materials Science, Multidisciplinary
Xiao Wang, Zhi-Yu Lind, Yu -Min Zhang, Jian-Feng Wang, Ke Xu
Summary: The effects of different substrates on the off-state leakage current in gallium nitride planar diodes are experimentally demonstrated and analyzed. Two devices with different substrates exhibit distinct leakage mechanisms despite the same process conditions. The leakage characteristics of these devices are described by different processes as the reverse bias increases, providing valuable insights for the design of planar gate transistors. Noteworthy observations include the presence of additional leakage channels in the device with a sapphire substrate and the shift of the leakage mechanism in the voltage range due to variations in the Schottky barrier height.
RESULTS IN PHYSICS
(2023)
Review
Thermodynamics
Saurabh Yadav, Jie Liu, Sung Chul Kim
Summary: This review paper discusses the importance of analyzing refrigerants for sustainable development, with a focus on the potential environmental impacts of different refrigerants in high-grade energy systems. Promising alternatives like R290 and R1234yf are highlighted, as well as the consequences of leakage and explosion in refrigeration systems. The study also explores the use of refrigerants in electric vehicle air conditioning systems to address potential future increases in global warming.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2022)
Article
Engineering, Multidisciplinary
Ali Safayet, Mohammad Islam, Tomy Sebastian
Summary: This article presents an analytical approach to determine the size of a dc-link capacitor for a three-phase current-controlled voltage-source inverter used in a permanent magnet synchronous motor. The approach takes into account the dc-link ripple voltage and capacitor ripple current, and analyzes the variation of the dc-link voltage ripple with the power factor and modulation index. The method can be used to determine the maximum ripple voltage for a given capacitor, or the minimum capacitance required to keep the voltage ripple within a certain limit. It also includes current ripple analysis to determine the root-mean-square capacitor ripple current, and capacitor life estimation analysis using the operating condition, thermal duty cycle, and ripple current.
IEEE TRANSACTIONS ON INDUSTRY APPLICATIONS
(2022)
Article
Chemistry, Physical
Hengjie Zhang, Chuantong Cheng, Beiju Huang, Huan Zhang, Run Chen, Yulong Huang, Hongda Chen, Weihua Pei
Summary: The introduction of a Pt/NiOx/WO3-x:Ti/W memristor structure has successfully achieved multiple conductance states and synaptic-like memory characteristics; the device exhibits good rectification performance under different pulse modulations; the structure proposed in this work has great significance for the integration of large-scale memristor cross arrays.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2021)
Article
Construction & Building Technology
Y. Gao, H. Han, Z. X. Ren, J. Q. Gao, S. X. Jiang, Y. T. Yang
Summary: This study explores sensitive parameters for seven typical faults in chillers and proposes a novel hybrid feature screening strategy. The screened feature sets exhibit good generalization performance and diagnostic reliability under different diagnosis methods, reducing the number of sensors significantly. Parameters of lubricating oil show immediate and significant indications of system status, recommending the installation of oil parameter sensors for early fault recognition.
ENERGY AND BUILDINGS
(2021)
Review
Electrochemistry
Shuting Zhang, Bofan Li, Chaojie Cui, Weizhong Qian, Yong Jin
Summary: This review summarizes the potential application of supercapacitors (SCs) in the field of alternating current filtering, including the working mechanism, progress in electrode materials, electrolytes, current collectors, and device configuration. The performance of SCs is comprehensively compared with that of commercial aluminum electrolyte capacitors (AECs) in terms of temperature, voltage, response time, impedance phase angle, and capacitance. Insights into future research focus for high-frequency SCs are provided in terms of mechanism, structural design, and application management.
BATTERIES & SUPERCAPS
(2023)
Review
Chemistry, Inorganic & Nuclear
Swarnalata Swain, Ali Altaee, Manav Saxena, Akshaya K. Samal
Summary: The production of suitable catalytic materials has expanded considerably in recent years, particularly with the emergence of single atom catalysts (SACs), which offer a greater number of active sites and high catalytic activity. However, the reduced size of particles can lead to increased surface activity of metals, resulting in aggregation and sintering. Therefore, it is necessary to develop appropriate strategies for the synthesis and stability of SACs. Additionally, the mass production of SACs remains challenging, making the development of bimetallic SACs crucial. This review provides a comprehensive overview of the development of SACs in various fields, highlighting different synthesis protocols and large-scale manufacturing strategies.
COORDINATION CHEMISTRY REVIEWS
(2022)
Review
Chemistry, Inorganic & Nuclear
Swarnalata Swain, Ali Altaee, Manav Saxena, Akshaya K. Samal
Summary: In recent years, single atom catalysts (SACs) have become a new research hotspot due to a greater number of active sites and high catalytic activity. However, the stability and large-scale production of SACs remain challenging. Therefore, the development of bimetallic SACs is crucial.
COORDINATION CHEMISTRY REVIEWS
(2022)
Article
Energy & Fuels
Michael Kempe, Peter Hacke, Joshua Morse, Jichao Li, Yu-Chen Shen, Katherine Han
Summary: This paper analyzes the mechanisms and pathways for leakage current flow observed in Si photovoltaic modules subjected to high temperature and humidity and a large voltage bias with respect to ground. The current inside of the frame is in the form of electron motion, but in the glass and polymer, it is in at least a large part attributable to the movement of ions. Here, we give a basic understanding of the charge/discharge of PV cells highlighting how the specific mechanisms are important in understanding some of the degradation processes in PV modules.
PROGRESS IN PHOTOVOLTAICS
(2023)
Article
Chemistry, Multidisciplinary
Yujie Huang, Jing Yang, Degang Zhao, Yuheng Zhang, Zongshun Liu, Feng Liang, Ping Chen
Summary: The dark leakage current of AlxGa1-xN Schottky barrier detectors with different Al contents was investigated. It was found that the dark leakage current increased with increasing Al content. XRD and SIMS results showed no significant difference in dislocation density and carbon impurity concentration among the samples, indicating that they were not the main reason for the difference in dark leakage current. However, positron annihilation results revealed an increase in vacancy defect concentration with increasing Al content, which was consistent with the increase in dark leakage current. This discovery is important for accurately controlling the performance of AlxGa1-xN detectors.
Article
Environmental Sciences
Yin-Chun Hung, Tung-Tsan Chen, Tsai-Fu Tsai, Hao-Xi Chen
Summary: Leakage is a serious problem in reservoir operation, affecting impoundment efficiency. The study on Qionglin Reservoir found no serious leakage, but improper development in the catchment area was identified as the main reason for its failure to impound water.
Article
Multidisciplinary Sciences
Takeaki Hamachi, Tetsuya Tohei, Yusuke Hayashi, Masayuki Imanishi, Shigeyoshi Usami, Yusuke Mori, Akira Sakai
Summary: The electrical characteristics and structures of threading dislocations (TDs) with a screw-component in GaN substrates were investigated to assess their effects on reverse leakage currents. Micrometer-scale platinum/GaN Schottky contacts were selectively fabricated on screw- and mixed-TD-related etch pits. The results showed that the leaky screw TDs exhibited anomalous reverse leakage currents due to different conduction mechanisms compared to other screw and mixed TDs, which were caused by variations in temperature and applied voltage.
SCIENTIFIC REPORTS
(2023)
Article
Materials Science, Multidisciplinary
Nikhil K. Ponon, Daniel J. R. Appleby, Erhan Arac, P. J. King, Srinivas Ganti, Kelvin S. K. Kwa, Anthony O'Neill
Article
Nanoscience & Nanotechnology
Sami Ramadan, Kelvin Kwa, Peter King, Anthony O'Neill
Article
Engineering, Manufacturing
Zi Jie Choong, Dehong Huo, Patrick Degenaar, Anthony O'Neill
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART B-JOURNAL OF ENGINEERING MANUFACTURE
(2016)
Article
Engineering, Electrical & Electronic
F. Arith, J. Urresti, K. Vasilevskiy, S. Olsen, N. Wright, A. O'Neill
IEEE ELECTRON DEVICE LETTERS
(2018)
Article
Physics, Applied
P. J. King, E. Arac, S. Ganti, K. S. K. Kwa, N. Ponon, A. G. O'Neill
APPLIED PHYSICS LETTERS
(2014)
Article
Physics, Applied
G. H. Wells, T. Hopf, K. V. Vassilevski, E. Escobedo-Cousin, N. G. Wright, A. B. Horsfall, J. P. Goss, A. G. O'Neill, M. R. C. Hunt
APPLIED PHYSICS LETTERS
(2014)
Article
Physics, Applied
T. Hopf, K. V. Vassilevski, E. Escobedo-Cousin, P. J. King, N. G. Wright, A. G. O'Neill, A. B. Horsfall, J. P. Goss, G. H. Wells, M. R. C. Hunt
JOURNAL OF APPLIED PHYSICS
(2014)
Article
Physics, Applied
Daniel J. R. Appleby, Nikhil K. Ponon, Kelvin S. K. Kwa, Srinivas Ganti, Ullrich Hannemann, Peter K. Petrov, Neil M. Alford, Anthony O'Neill
JOURNAL OF APPLIED PHYSICS
(2014)
Article
Chemistry, Multidisciplinary
Daniel J. R. Appleby, Nikhil K. Ponon, Kelvin S. K. Kwa, Bin Zou, Peter K. Petrov, Tianle Wang, Neil M. Alford, Anthony O'Neill
Article
Multidisciplinary Sciences
Harbaljit S. Sohal, Gavin J. Clowry, Andrew Jackson, Anthony O'Neill, Stuart N. Baker
Article
Engineering, Electrical & Electronic
J. Urresti, F. Arith, S. Olsen, N. Wright, A. O'Neill
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2019)
Article
Engineering, Chemical
Guangru Zhang, Dragos Neagu, Peter J. King, Sami Ramadan, Anthony O'Neill, Ian S. Metcalfe
Summary: Perovskite oxides with mixed ionic and electronic conductivity are of interest for oxygen separation membranes, but they often degrade due to segregation and reaction with sulfur-based species in natural gas. Coating these membranes with Alumina layers by atomic layer deposition can delay or prevent degradation, with a critical coating thickness of around 30 nm showing no negative effect on O-2 transport flux and good flux recovery after H2S removal. Thinner coatings provide little protection against poisoning, while thicker coatings significantly decrease O-2 permeation fluxes.
JOURNAL OF MEMBRANE SCIENCE
(2021)
Article
Engineering, Electrical & Electronic
George H. Wells, Michael R. C. Hunt, Toby Hopf, Konstantin V. Vassilevski, Enrique Escobedo-Cousin, Alton B. Horsfall, Jonathan P. Goss, Anthony O'Neill
JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B
(2015)
Proceedings Paper
Crystallography
Enrique Escobedo-Cousin, Konstantin Vassilevski, Toby Hopf, Nick Wright, Anthony O'Neill, Alton Horsfall, Jonathan Goss
SILICON CARBIDE AND RELATED MATERIALS 2013, PTS 1 AND 2
(2014)
Proceedings Paper
Crystallography
Toby Hopf, Konstantin Vassilevski, Enrique Escobedo-Cousin, Nick Wright, Anthony O'Neill, Alton Horsfall, Jonathan Goss, Anders Barlow, George Wells, Michael Hunt
SILICON CARBIDE AND RELATED MATERIALS 2013, PTS 1 AND 2
(2014)