Article
Computer Science, Information Systems
Abdullah Al Hadi, Xingang Fu, Eklas Hossain, Rajab Challoo
Summary: This study evaluates the performance of GaN-based inverters in high-power applications using simulations and hardware experiments. A five-level GaN-based cascaded H-bridge inverter controlled by a TI microcontroller was used for the experiment. Simulations were conducted to showcase different inverter topologies and PWM generation. The experiment utilized GaN-based components and demonstrated promising results for high-power applications.
Article
Energy & Fuels
Qiuyang Tan, Liansheng Mao, Yunlong Cai, Baoyu Zhang, Zhaozhong Ruan
Summary: This paper presents a SPICE-based assessment platform for fast-switching GaN devices-based VSIs and CSIs. The previous research revealed problems with the direct replacement of WBG switches in VSIs, so the CSI topology is chosen as a viable alternative for WBG-based devices. The GaN device is selected as a promising candidate among all WBG devices. Tailored DPT is used to characterize the GaN switch in VSI and CSI topologies, and the SPICE model is modified accordingly. A dedicated SVPWM modulation scheme for three-phase CSI is introduced, taking into account the parasitic elements associated with the DPT-PCB layout for accuracy. VSI and CSI circuits are built in LTspice with the modified GaN switch SPICE model for precise analysis under a wide range of operating conditions.
Article
Engineering, Electrical & Electronic
Pablo Guillen, Hector Sarnago, Oscar Lucia, Jose Miguel Burdio
Summary: Flexible-surface induction cooktops have the challenge of operating with different induction heating loads simultaneously. Multioutput inverter topologies are proposed to manage these loads efficiently with low power-device count and high power density. However, traditional modulation strategies face limitations in achieving soft switching. This study introduces the use of wide bandgap devices, specifically GaN HEMTs, in a multioutput resonant inverter, and evaluates various modulation strategies for efficiency under different switching modes through a prototype implementation.
IEEE TRANSACTIONS ON POWER ELECTRONICS
(2023)
Article
Computer Science, Information Systems
Ivan Patrao, Marian Liberos, Raul Gonzalez-Medina, Enric Toran, Emilio Figueres, Gabriel Garcera
Summary: Photovoltaic transformerless inverters are efficient and economical options for solar-power generation, but they can have high-frequency voltage to ground and high-leakage currents due to the absence of isolation transformers. By using half-bridge topologies and multilevel half-bridge inverters, the leakage to ground can be reduced and the output quality can be improved. The NPC + GCC topology is a multilevel single-phase transformerless inverter that can track the maximum power point of two photovoltaic sources simultaneously. This paper presents the control structure and dynamic modeling of the NPC + GCC inverter, including the stability margins of the current and voltage loops.
Article
Engineering, Electrical & Electronic
Ranran Wang, Lifang Jia, Xingfa Gao, Jiaheng He, Zhe Cheng, Zhe Liu, Lian Zhang, Yun Zhang
Summary: This study demonstrates the high-temperature operation of AlGaN/GaN high electron mobility transistors (HEMTs) and direct-coupled FET logic (DCFL) inverters, NOR gates, and NAND gates. The p-GaN-gate HEMTs used in DCFL circuits exhibit proper E-mode operation with stable threshold voltage and high electron mobility at 300 degrees C. The fabricated logic gates have a small switching time at room temperature and exhibit a slight increase in switching time at 300 degrees C, while still maintaining accurate and stable operation.
IEEE ELECTRON DEVICE LETTERS
(2023)
Article
Chemistry, Physical
Chih-Shan Tan, Michael H. Huang
Summary: Density functional theory calculations reveal that GaN crystals with different numbers of layers and different crystal planes exhibit distinct band structures and bond lengths. These findings suggest that surface layer structural deviations may influence the properties of materials.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Energy & Fuels
Yajing Zhang, Jianguo Li, Jiuhe Wang, Trillion Q. Zheng, Pengyu Jia
Summary: In this paper, the dynamic process of a photovoltaic inverter based on GaN HEMT is analyzed in detail, and the influence of parasitic parameters on the performance is considered. The correctness of theoretical and simulation analysis is verified through experiments.
Article
Engineering, Electrical & Electronic
Michael Antivachis, Nicolas Kleynhans, Johann W. Kolar
Summary: This article presents a promising Y-voltage source inverter (VSI) topology, which effectively copes with the wide variation of the fuel-cell/battery voltage. Each phase-module of the Y-VSI can be operated independently and controlled easily. In addition, the Y-VSI features an integrated output filter, eliminating the need for an additional filter between the inverter and the motor, and allowing for continuous/sinusoidal motor voltage waveforms.
IEEE JOURNAL OF EMERGING AND SELECTED TOPICS IN POWER ELECTRONICS
(2022)
Article
Chemistry, Analytical
Li-Fang Jia, Lian Zhang, Jin-Ping Xiao, Zhe Cheng, De-Feng Lin, Yu-Jie Ai, Jin-Chao Zhao, Yun Zhang
Summary: In this study, AlGaN/GaN E/D-mode GaN inverters were successfully fabricated on a 150-mm Si wafer and a systematic analysis of their key electrical characteristics was conducted from room temperature to 200 degrees C. The results demonstrate the small variations of inverters at different temperatures and the great potential for GaN smart power integrated circuit (IC) application.
Article
Chemistry, Multidisciplinary
Teodoro Garcia-Millan, Thomas A. Swift, David J. Morgan, Robert L. Harniman, Benjamin Masheder, Stephen Hughes, Sean A. Davis, Thomas A. A. Oliver, M. Carmen Galan
Summary: This study describes the synthesis and structural characterization of carbon dots with distinct physicochemical properties. We found that small changes in reaction conditions lead to changes in the fluorescent behavior of the carbon dots, especially in the selective enhancement of fluorescence bands. Additionally, we demonstrate that these carbon dots have distinct reversible response to pH changes.
Article
Geochemistry & Geophysics
Jun-Hyung Kim, Youngbae Hwang
Summary: This study proposes a method for generating synthetic training data for infrared small target detection, addressing the scarcity of training data. The generative adversarial network framework is adopted to generate synthetic background images and infrared small targets through independent processes. Experimental results demonstrate that training detection networks using a dataset composed of both real and synthetic images leads to better performance compared to using real data only.
IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING
(2022)
Article
Multidisciplinary Sciences
Yijing Guo, Linwei Zhong, Yi Qiu, Huawei Wang, Fengqiang Gao, Zongheng Wen, Choujun Zhan
Summary: Surface defect detection is a vital process in industrial production and a significant research direction in computer vision. This paper proposes a new unsupervised small sample defect detection model that improves detection accuracy and defect profile extraction by enhancing the feature extraction capability of the generator and introducing an SSIM-based defect segmentation method.
SCIENTIFIC REPORTS
(2022)
Article
Chemistry, Physical
Mohamed Almokhtar, Naglaa Abdel All, Jamal Q. M. Almarashi, Hajime Asahi
Summary: Small GaN nanorods exhibit unique photoluminescence features due to enhanced surface effects and strong electron-phonon coupling, with the majority of excitons occupying the surface shell. These findings have significant implications for applications in optoelectronics, UV and blue lasers, and high-temperature/high-power electronic devices.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Energy & Fuels
Xin Zhang, Lijiao Gong, Xinyu Zhao, Rongrong Li, Li Yang, Bin Wang
Summary: This study aims to improve the voltage and frequency support capacity of power systems with large scale Inverter-based Resources (IBR) penetration. The control blocks of virtual synchronous generator (VSG) are restructured based on traditional synchronous generators' control, simplifying the control path for active and reactive power output. An improved VSG voltage and frequency regulation control strategy is proposed, and the stability analysis is conducted to enhance system stability and robustness.
Article
Computer Science, Information Systems
Alla Eddine Toubal Maamar, M'Hamed Helaimi, Rachid Taleb, Mostefa Kermadi, Saad Mekhilef, Addy Wahyudie, Muhyaddin Rawa
Summary: This paper presents the implementation of a small-signal model for a new five-level series resonant inverter structure, which combines the advantages of multilevel inverters and resonance characteristics. The small-signal model demonstrates good accuracy in frequency and time domains, making it suitable for high-voltage high-frequency applications. The suggestion of using small-signal AC analysis for multilevel series resonant inverter modeling is a key takeaway from the results obtained in this study.
Article
Physics, Condensed Matter
Xuerui Niu, Xiaohua Ma, Meng Zhang, Ling Yang, Bin Hou, Mei Wu, Fuchun Jia, Xinchuang Zhang, Chong Wang, Yue Hao
Summary: This article explores a promising solution for resolving parasitic problems and fully leveraging the advantages of GaN-based high electron mobility transistors through monolithic integration of different function blocks. It focuses on the enhancement mode GaN-based p-channel heterostructure field-effect transistor (p-HFET) as a key component and models the threshold voltage (V-TH) while investigating the influence of Mg out-diffusion effect. The study takes into consideration factors such as Mg diffusion coefficient, Mg concentration in the p-GaN layer, thicknesses of the AlGaN layer, p-GaN channel layer, and oxide layer to systematically explore their impact on V-TH. The analysis reveals that lower Mg concentration, smaller diffusion coefficient, and thinner p-GaN channel and AlGaN layers facilitate the realization of E-mode p-HFETs. It also suggests a heterostructure with two p-GaN layers of different concentrations to simplify the etching technique while improving ohmic contacts. Overall, this model effectively guides the design of GaN-based E-mode p-HFETs.
PHYSICA STATUS SOLIDI B-BASIC SOLID STATE PHYSICS
(2023)
Article
Computer Science, Information Systems
Yilin Chen, Qing Zhu, Jiejie Zhu, Minhan Mi, Meng Zhang, Yuwei Zhou, Ziyue Zhao, Xiaohua Ma, Yue Hao
Summary: This study investigates the negative shift of threshold voltage and degradation of leakage current in a Si3N4/AlGaN/GaN metal-insulator-semiconductor high electron mobility transistor under UV light. The increase in leakage current is observed due to the capture of holes generated by UV illumination, while blue light and darkness do not have the same effect. Simulation results show that the trapped holes significantly increase the electric field strength in Si3N4.
SCIENCE CHINA-INFORMATION SCIENCES
(2023)
Article
Engineering, Electrical & Electronic
Junjie Yang, Jin Wei, Yanlin Wu, Muqin Nuo, Zhenghao Chen, Xuelin Yang, Maojun Wang, Bo Shen
Summary: A 600-V p-GaN gate HEMT with a buried hole spreading channel (BHSC) is demonstrated to suppress the buffer trap related dynamic R-ON degradation. The BHSC, located between u-GaN and buried AlGaN, enables effective spreading of holes along its channel to screen the negative buffer charges injected from the gate. This spreading effect is verified by detection of hole current from the sidewall of BHSC. The proposed device exhibits immunity against buffer trapping, as demonstrated by a positive substrate stress test, achieving nearly zero buffer trap related dynamic R-ON degradation even after a 400-V substrate stress with a delay as short as approximately 20 μs.
IEEE ELECTRON DEVICE LETTERS
(2023)
Article
Engineering, Electrical & Electronic
Yanlin Wu, Jin Wei, Maojun Wang, Muqin Nuo, Junjie Yang, Wei Lin, Zheyang Zheng, Li Zhang, Mengyuan Hua, Xuelin Yang, Yilong Hao, Kevin J. Chen, Bo Shen
Summary: The active-passivation pGaN gate HEMT (AP-HEMT) is demonstrated on a commercial E-mode pGaN/AlGaN/GaN heterostructure wafer. The active passivation layer effectively shields the surface traps and improves the dynamic R-on. Compared to the conventional HEMT, the AP-HEMT has a significantly lower dynamic R-on under V-DS stress.
IEEE ELECTRON DEVICE LETTERS
(2023)
Article
Engineering, Electrical & Electronic
Shaozhong Yue, Xuefeng Zheng, Yuehua Hong, Xiangyu Zhang, Fang Zhang, Yingzhe Wang, Xiaohua Ma, Yue Hao
Summary: This study investigates the effect of neutron irradiation on the electrical performance of the beta-Ga2O3 Schottky barrier diode (SBD) device. The results show that after neutron irradiation, there is a decrease in forward current density (J(F)), reduction in reverse current density (J(R)), and increase in breakdown voltage (V-br) based on current-voltage (I-V) measurements. The density of interface states slightly increases, and there is an increase in trap activation energy after neutron irradiation according to frequency-dependent conductance technique. The carrier concentration across the Ga2O3 drift layer decreases after neutron irradiation based on capacitance-voltage (C-V) measurements.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2023)
Article
Immunology
Sifang Xiao, Ting Zhou, Jianhua Pan, Xiaohua Ma, Guomin Shi, Binyuan Jiang, Yan-gen Xiang
Summary: This study found a correlation between autophagy and immune infiltration in tuberculosis, and identified FOXO1 as a potential gene target for TB immunotherapy. These findings provide new insights into diagnostic and immuno-therapy strategies for clinical tuberculosis.
INTERNATIONAL IMMUNOPHARMACOLOGY
(2023)
Article
Biotechnology & Applied Microbiology
Baoqi Li, Mengmeng Zhang, Weinan Sun, Dandan Yue, Yizan Ma, Boyang Zhang, Lingfeng Duan, Maojun Wang, Keith Lindsey, Xinhui Nie, Xianlong Zhang, Xiyan Yang
Summary: N-6-methyladenosine (m(6)A) is a common modification in mRNAs and plays a role in drought stress response in cotton. The study found that m(6)A levels change significantly under drought stress, and higher levels of m(6)A are associated with increased mRNA abundance and drought resistance. The demethylase GhALKBH10B regulates m(6)A levels and affects the mRNA decay of ABA and Ca2+ signal-related genes, while mutation of GhALKBH10B enhances drought resistance in cotton seedlings. Silence of Ca2+-related genes GhECA1 and GhCNGC4 reduces drought resistance by decreasing m(6)A enrichment.
PLANT BIOTECHNOLOGY JOURNAL
(2023)
Review
Biology
Xingpeng Wen, Zhiwen Chen, Zuoren Yang, Maojun Wang, Shuangxia Jin, Guangda Wang, Li Zhang, Lingjian Wang, Jianying Li, Sumbul Saeed, Shoupu He, Zhi Wang, Kun Wang, Zhaosheng Kong, Fuguang Li, Xianlong Zhang, Xiaoya Chen, Yuxian Zhu
Summary: Cotton is an economic crop with elongated fiber cells that have been extensively studied in terms of multi-genome assembly, genome editing, fiber development mechanism, and metabolite biosynthesis. Research has revealed the origin of cotton species, asymmetric chromatin structure in fibers, and the role of candidate genes in fiber development. The synthesis of secondary metabolites, resistance to diseases, and plant architecture regulation have also been investigated. This review summarizes the important achievements in cotton molecular biology and provides theoretical support for future research.
SCIENCE CHINA-LIFE SCIENCES
(2023)
Review
Chemistry, Multidisciplinary
Rui Wang, Wanlin Zhang, Saisai Wang, Tonglong Zeng, Xiaohua Ma, Hong Wang, Yue Hao
Summary: This article systematically presents the requirements, mechanisms, and implementation methods of memristor-based compressed sensing (CS) technology, as well as its potential in all-in-one compression and encryption. The article points out the lack of a comprehensive overview of memristor-based CS techniques.
Article
Clinical Neurology
Xiaoyan Liu, Ziqi Fan, Xuanyu Chen, Yanyan Zhang, Fangping He, Xiaohua Ma, Qing Ke
Summary: This article presents a rare case of anti-IgLON5 disease, a novel autoimmune encephalopathy, in a patient with rapidly progressive dementia (RPD). The patient exhibited overlapping sleep dysfunction, psychosis, and abnormal movement. The study highlights the importance of considering anti-IgLON5 disease as a potential differential diagnosis in RPD patients, and suggests that early initiation of immunotherapy may not yield favorable outcomes.
FRONTIERS IN NEUROLOGY
(2023)
Article
Polymer Science
Lu-Jun Huang, Ya-Tao Weng, Aqib Raiz, Zhi-Jie Mao, Xiao-Hua Ma
Summary: In this study, two intrinsic microporous polyimides (6FPCA and 6FMCA) with high permeability, selectivity, and stability were successfully constructed. These polyimides were derived from two isometric diamines (PCA and MCA) and exhibited a hollow beaded structure with a specified window size. Compared to the corresponding polyimide with a plane structure, these polyimides showed larger microporosity, higher permeability, and minimal decrease in selectivity. This study demonstrates that incorporating the paracyclophane subunit into polymers can enhance their ultra-microporosity and separation properties.
CHINESE JOURNAL OF POLYMER SCIENCE
(2023)
Article
Engineering, Chemical
Jia-Hao Liu, Fei Xie, Han-Zhuo Ding, Jia-Wei Mo, Xiao-Gang Jin, Xiao-Hua Ma, Zhen-Liang Xu
Summary: This study introduces chitosan (CS) nanofibers interlayer to optimize the substrate and improve the separation performance of thin-film composite (TFC) membranes. The introduction of CS nanofibers prevents polyamide invasion, promotes interfacial polymerization (IP) reaction, and enhances the hydrophilicity of the membrane. The TFC/CS/PES membrane shows excellent separation performance with a 4.5 times increase in permeance and a high MgCl2 rejection rate. This work provides a new strategy for substrate optimization and membrane improvement.
Article
Chemistry, Physical
Junli Nie, Bingqiang Niu, Yijin Wang, Zhang He, Xingmao Zhang, HuanHuan Zheng, Yimin Lei, Peng Zhong, Xiaohua Ma
Summary: This study focuses on the synthesis of zero-dimensional MXene quantum dots (MQDs) and their incorporation into perovskite solar cells (PSCs). The MQDs demonstrate unique optical properties and display multi-functionality when incorporated into the SnO2 electron transport layer of PSCs. This results in improved charge transport, reduced nonradiative recombination, increased power conversion efficiency, and enhanced stability of the devices.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2023)
Article
Engineering, Chemical
Qing Ju, Hongying Tang, Hao Dong, Kang Geng, Huidong Qian, Xiaohua Ma, Nanwen Li
Summary: A novel triptycene-based polybenzimidazole (Trip-PBI) material was obtained for the first time and used as a PEM or binder in high-temperature proton exchange membrane fuel cells (HT-PEMFC). By using Trip-PBI as a binder, the issues of gas transfer restriction and excessive PA diffusion in the PEM to the catalysis layer have been successfully addressed. As a result, the MEA with Trip-PBI as the binder exhibits a maximum power density of 700 mW/cm2 at 160 degrees C, which is 1.84 times that of m-PBI and 1.36 times that of PTFE. Moreover, the H2/O2 cell using Trip-PBI binder also shows good stability for 100 h at 160 degrees C with a current density of 0.3 A/cm2.
JOURNAL OF MEMBRANE SCIENCE
(2023)
Article
Engineering, Chemical
Hongfang Guo, Jing Wei, Yulei Ma, Zikang Qin, Xiaohua Ma, Roman Selyanchyn, Bangda Wang, Xuezhong He, Bo Tang, Lin Yang, Lu Yao, Wenju Jiang, Yuanfa Zhuang, Dengguo Yin, Xue Li, Zhongde Dai
Summary: The use of a novel porogen in the precursor of the Troger's base polymer allows for the reduction of carbonization temperature, leading to the fabrication of carbon molecular sieve membranes with high gas permeability and selectivity.
SEPARATION AND PURIFICATION TECHNOLOGY
(2023)
