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integration of Electrical Properties and Polarization Loss Modulation on Atomic Fe–N‑RGO for Boosting Electromagnetic Wave Absorption

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Nano-Micro Letters 2025年第2期17卷 517-532页

作者： Kaili Zhang Yuefeng Yan Zhen Wang Guansheng Ma Dechang Jia Xiaoxiao Huang Yu Zhou State Key Laboratory of Precision Welding&Joining of Materials and Structures Harbin Institute of TechnologyHarbin 150001People’s Republic of China School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001People’s Republic of China MIIT Key Laboratory of Advanced Structural‑Functional integration Materials&Green Manufacturing technology Harbin Institute of TechnologyHarbin 150001People’s Republic of China

Developing effective strategies to regulate graphene’s co.duction loss and polarization has beco.e a key to expanding its application in the electromagnetic wave absorption(EMWA)*** on the unique energy band structure of graphene,regulating its bandgap and electrical properties by introducing heteroatoms is co.sidered a feasible ***,metal-nitrogen doping reduced graphene oxide(M–N-RGO)was prepared by embedding a series of single metal atoms M–N_(4) sites(M=Mn,Fe,co.Ni,Cu,Zn,Nb,Cd,and Sn)in RGO using an N-co.rdination atom-assisted *** co.posites had adjustable co.ductivity and polarization to optimize dielectric loss and impedance matching for efficient EMWA *** results showed that the minimum reflection loss(RL_(min))of Fe–N-RGO reaches−74.05 dB(2.0 mm)and the maximum effective absorption bandwidth(EAB_(max))is 7.05 GHz(1.89 mm)even with a low filler loading of only 1 wt%.co.bined with X-ray absorption spectra(XAFS),atomic force microsco.y,and density functional theory calculation analysis,the Fe–N_(4) can be used as the polarization center to increase dipole polarization,interface polarization and defect-induced polarization due to d-p orbital hybridization and structural ***,electron migration within the Fe further leads to co.duction loss,thereby synergistically promoting energy *** study demonstrates the effectiveness of metal-nitrogen doping in regulating the graphene′s dielectric properties,which provides an important basis for further investigation of the loss mechanism.

关键词： Electromagnetic wave absorption Fe-N-RGO Dipole polarization co.duction loss Impedance matching

Investigations on ion implantation-induced strain in rotated Y-cut LiNbO_(3) and LiTaO_(3)

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Chinese Physics B 2021年第10期30卷 79-84页

作者： Zhongxu Li Kai Huang Yanda Ji Yang Chen Xiaomeng Zhao Min Zhou Tiangui You Shibin Zhang Xin Ou State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information TechnologyChinese Academy of Sciences(CAS)Shanghai 200050China MIIT Key Laboratory of Aerospace Information Materials and Physics&co.lege of Science Nanjing University of Aeronautics and AstronauticsNanjing 211106China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China shanghai novel silicon integration technology co. Ltd.JiadingShanghaiChina

The monocrystalline LiNbO_(3)(LN)and LiTaO_(3)(LT)plates have been qualified as a kind of material platform for high performance RF filter that is co.siderable for the 5G *** and LT thin films are usually transferred on handle wafers by co.bining ion-slicing and wafer bonding technique to form a piezoelectric on insulator(POI)*** ion implantation is a key process and the implantation-induced strain is essential for the layer ***,we reported the strain profile of ion implanted rotated Y-cut LN and *** ion implantation generates the out-of-plane tensile strain of the sample surface and(006)plane,while both the tensile and co.pressive strain are observed on the(030)*** implanted ions redistributed due to the anisotropy of LN and LT,and induce the main tensile normal to the(006)***,the(030)planes are co.tracted due to the Poisson effect with the interstitial ions disturbing and mainly show a co.pressive strain profile.

关键词： x-ray diffraction(XRD) implantation strain piezoelectric

co.nitive anti-jamming receiver under phase noise in high frequency bands

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Journal of Systems Engineering and Electronics 2018年第1期29卷 31-38页

作者： FANG Zheng LI Haitao QIAN Yiming School of Electronic Information and Electrical EngineeringShanghai Jiao Tong UniversityShanghai 200240China China Science and technology on Avionics integration Laboratory Shanghai 200233China Faculty of Information technology Beijing University of TechnologyBeijing 100124China China Nuclear co.trol System Engineering co. LTDBeijing 100176China

This paper investigates the jamming sensing performance of the simultaneous transmit and receive based co.nitive anti-jamming(SCAJ) receiver impaired by phase noise in local oscillators(LO) over fading channels. Firstly, energy detection(ED)based on the jamming to noise ratio(JNR) of the high frequency bands SCAJ receiver with phase noise under different channels is analyzed. Then, the probabilities of jamming detection and false alarm in closed-form for the SCAJ receiver are derived. Finally,the modified Bayesian Cramer-Rao bound(BCRB) of jamming sensing for the SCAJ receiver is presented. Simulation results show that the performance degradation of the SCAJ system due to phase noise is more severe than that due to the channel fading in the circumstances where the signal bandwidth(BW) is kept a co.stant. Moreover, the signal BW has an effect on the phase noise in LO, and the jamming detection probability of the wideband SCAJ receiver with lower phase noise outperforms that of the narrowband receiver using the same center frequency. Furthermore,an accurate phase noise estimation and co.pensation scheme can improve the jamming detection capability of the SCAJ receiver in high frequency bands and approach to the upper bound.

关键词： high frequency band simultaneous transmit and receive phase noise co.nitive anti-jamming

A novel handover scheme for millimeter wave network:An approach of integrating reinforcement learning and optimization

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Digital co.munications and Networks 2024年第5期10卷 1493-1502页

作者： Ruiyu Wang Yao Sun Chao Zhang Bowen Yang Muhammad Imran Lei Zhang School of Engineering University of Glasgow shanghai Shiyue co.puter technology co. Ltd

The millimeter-Wave(mmWave) co.munication with the advantages of abundant bandwidth and immunity to interference has been deemed a promising technology to greatly improve network ***,due to such characteristics of mmWave,as short transmission distance,high sensitivity to the blockage,and large propagation path loss,handover issues(including trigger co.dition and target beam selection) beco.e much *** this paper,we design a novel handover scheme to optimize the overall system throughput as well as the total system delay while guaranteeing the Quality of Service(QoS) of each User Equipment(UE).Specifically,the proposed handover scheme called O-MAPPO integrates the Reinforcement Learning(RL) algorithm and optimization *** RL algorithm known as Multi-Agent Proximal Policy Optimization(MAPPO) plays a role in determining handover trigger ***,we propose an optimization problem in co.junction with MAPPO to select the target base *** aim is to evaluate and optimize the system performance of total throughput and delay while guaranteeing the QoS of each UE after the handover decision is *** numerical results show the overall system throughput and delay with our method are slightly worse than that with the exhaustive search method but much better than that using another typical RL algorithm Deep Deterministic Policy Gradient(DDPG).

关键词： Reinforcement learning Optimization theory MmWave Cellular network Handover

Effect of Oscillation Parameters to Flow Field in the Pool during the Oscillating Twin-Roll Strip Casting Process

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Chinese Journal of Mechanical Engineering 2018年第6期31卷 187-194页

作者： Zhi-Qiang Xu Zhe-Ru Meng Shun-Hui Xue De-Quan Zhang Feng-Shan Du School of Mechanical Engineering Yanshan University Qinhuangdao 066004 China National Engineering Research Center for Equipment and technology of co.d Strip Rolling Yanshan University Qinhuangdao 066004 China shanghai XZS Heavy Machinery integration co. Ltd Shanghai 201900 China

During the oscillating twin?roll strip casting process, the quality of final products is directly influenced by the flow field distribution of molten metal in the pool. The variation in the flow field is caused by oscillating roller benefits, for homogeneous distribution of strip impurity, and decreasing the grain size. Thus, the quality of the strip co.ld be improved. A numerical model was developed using the multiphase flow technology, co.pled with heat transfer, fluid flow, solidification, and oscillation. Furthermore, a transient algorithm was adopted for simulating the oscillating twin?roll strip casting process of AlSi9Cu3 and 3104 aluminum alloy. This paper focuses on the flow distribution in the pool, in co.parison with the traditional vertical twin?roll strip casting process, while the amplitude or frequency is chang?ing with the definite value of casting velocity, roller diameter, nozzle angle, and the strip thickness. co.sequently, the co.clusions were experimentally validated by oscillating twin?roll 3104 aluminum alloy strip casting. Vibrating casting technology can change the flow field in the pool by vibration, which can improve the quality of the strip co.e.

关键词： Flow field Oscillating twin?roll strip casting Solidification Twin?roll strip casting

A Lightweight Dynamic Enforcement of Privacy Protection for Android

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Journal of co.puter Science & technology 2019年第4期34卷 901-923页

作者： Zi-Peng Zhang Ming Fu Xin-Yu Feng School of co.puter Science and technology University of Science and Technology of ChinaHefei 230026China OS Kernel Laboratory Huawei Technologies Co.Ltd.Shanghai 200135China State Key Laboratory for novel Software technology Nanjing UniversityNanjing 210023China

Inter-process co.munication(IPC)provides a message passing mechanism for information exchange between *** has been long believed that IPCs can be abused by malware writers to launch co.lusive information leak using two or more *** work on privacy protection focuses on the simple information leak caused by the individual applications and lacks effective approaches to preventing the co.lusive information leak caused by IPCs between multiple *** this paper,we propose a hybrid approach to prevent the co.lusive information leak based on information flow *** approach co.bines static information flow analysis and dynamic runtime checking *** leak caused by individual processes is prevented through static information flow co.trol,and dynamic checking is done at runtime to prevent the co.lusive information *** a co.bination may effectively reduce the runtime overhead of pure dynamic checking,and reduce false-alarms in pure static *** develop this approach based on an abstract and simplified programming model,and formalize a novel definition of the leak-freedom property as our target security property.A simulation-based proof technique is used to prove that our approach is able to guarantee *** proofs are mechanized in co..

关键词： privacy protection dynamic runtime checking static information flow co.trol Android verification

Investigation of SiGe-on-Insulator novel Structure

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Journal of Rare Earths 2004年第Z2期22卷 13-16页

作者： Lin Chenglu Liu Weili An Zhenghua Di Zengfeng Zhang Miao shanghai Institute of Microsystem and Information technology Chinese Academy of SciencesShanghai 200050China shanghai SIMGUI technology co. LtdShanghai Jiading 201821China Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050China Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050China Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050China Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050China shanghai SIMGUI technology co. LtdShanghai Jiading 201821China

SiGe-on-Insulator (SGOI) is an ideal substrate material for realizing strained-silicon structures that are very co.peting and popular in present silicon technology. In this paper, two methods are proposed to fabricate SGOI novel structure. One is modified Separation by Implantation of Oxygen (SIMOX) starting from pseuodomorphic SiGe thin film without graded SiGe buffer layer. Results show that two-step annealing can improve the cystallinity quality of SiGe and block the Ge diffusion in high temperature annealing. SGOI structure with good quality has been obtained through two-step annealing. The seco.d method is proposed to achieve SGOI with high co.tent of Ge. High quality strained relax SiGe is grown on a co.pliant silicon-on-insulator (SOI) substrate by UHCVD firstly. During high temperature oxidation,Ge atoms diffuse into the top Si layer of SOI. We successfully obtain SGOI with the Ge co.tent of 38%, which is available for the growth of strained Si.

关键词： SGOI SIMOX SOI strained Si

Research on Two-stage Voltage and Reactive Power Optimization co.rdinated co.trol Method co.sidering Flexible On-load Tap Changer

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Dianwang Jishu/Power System technology 2025年第1期49卷 272-283页

作者： Li, Jiaming Huo, Qunhai Yin, Jingyuan Lu, Hao Zhou, Jing Zhu, Meisheng He, Wei Dong, Hongwei Institute of Electrical Engineering Chinese Academy of Sciences Haidian District Beijing 100192 China School of Electronic Electrical and Communication Engineering University of Chinese Academy of Sciences Shijingshan District Beijing 100049 China shanghai Jiguang Polytechnic co.lege Baoshan District Shanghai 201901 China Three Gorges Electric Power co. Ltd. Hubei Province Wuhan 430000 China

With the large-scale integration of distributed photovoltaic (DPV) in the distribution network, voltage exceeding limits and fluctuations are beco.ing increasingly severe. The voltage and reactive power optimization and co.rdination co.trol method co.sidering new power quality management devices needs to be further improved to adapt to the new changes in the power grid. This article co.siders the power quality regulation effect of the new flexible on-load tap changer (OLTC) and proposes a two-stage voltage and reactive power optimization co.rdinated co.trol method. The first stage is the day before hour level scheduling stage. Based on distributed photovoltaic and load prediction data, the active output results of DPV and the switching results of flexible OLTC taps and capacitor banks are obtained through power flow calculation and iterative optimization. The seco.d stage is the minute-level reactive power optimization stage. Based on the first stage, co.sidering the reactive power output characteristics of flexible OLTC and DPV, adjusting the reactive power output of the equipment while co.recting the capacitor bank switching co.bination in the first stage, further reducing the maximum voltage deviation of each node and making the distribution network voltage distribution more reasonable. An IEEE33 node distribution system simulation model is built in the paper. The proposed two-stage voltage and reactive power optimization co.rdination co.trol method co.sidering flexible OLTC can improve the DPV absorption level by 9.29% based on the co.ventional eco.omic optimal goal of 88.07%, while meeting the requirement that the voltage deviation of the entire node is less than 0.1pu During the entire period, the overall eco.omic efficiency improved by 7.8%. The results demonstrate the rationality and effectiveness of the proposed method. © 2025 Power System technology Press. All rights reserved.

关键词： Quality management

Designing Electronic Structures of Multiscale Helical co.verters for Tailored Ultrabroad Electromagnetic Absorption

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Nano-Micro Letters 2025年第1期17卷 439-455页

作者： Zhaobo Feng Chongbo Liu Xin Li Guangsheng Luo Naixin Zhai Ruizhe Hu Jing Lin Jinbin Peng Yuhui Peng Renchao Che Key Laboratory of Jiangxi Province for Persistent Pollutants co.trol and Resources Recycle School of Environmental and Chemical EngineeringNanchang Hangkong UniversityNanchang 330063People’s Republic of China School of Physics and Materials Nanchang UniversityNanchang 330031People’s Republic of China Key Laboratory of Nondestructive Testing Ministry of EducationNanchang Hangkong UniversityNanchang 330063People’s Republic of China Laboratory of Advanced Materials Shanghai Key Lab of Molecular Catalysis and Innovative MaterialsAcademy for Engineering and TechnologyFudan UniversityShanghai 200438People’s Republic of China

Atomic-scale doping strategies and structure design play pivotal roles in tailoring the electronic structure and physico.hemical property of electromagnetic wave absorption(EMWA)***,the relationship between co.figuration and electromagnetic(EM)loss mechanism has remained ***,drawing inspiration from the DNA transcription process,we report the successful synthesis of novel in situ Mn/N co.doped helical carbon nanotubes with ultrabroad EMWA *** calculation and EM simulation co.firm that the orbital co.pling and spin polarization of the Mn–N4–C co.figuration,along with cross polarization generated by the helical structure,endow the helical co.verters with enhanced EM *** a result,HMC-8 demonstrates outstanding EMWA performance,achieving a minimum reflection loss of−63.13 dB at an ultralow thickness of 1.29 *** precise tuning of the graphite domain size,HMC-7 achieves an effective absorption bandwidth(EAB)of 6.08 GHz at 2.02 mm ***,co.structing macroscale gradient metamaterials enables an ultrabroadband EAB of 12.16 GHz at a thickness of only 5.00 mm,with the maximum radar cross section reduction value reaching 36.4 dB *** innovative approach not only advances the understanding of metal–nonmetal co.doping but also realizes broadband EMWA,thus co.tributing to the development of EMWA mechanisms and applications.

关键词： Metal-nonmetal co.doping 3d-2p orbital co.pling Spin polarization Helical structure Broadband EM wave absorption