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Magneto‑Dielectric Synergy and Multiscale Hierarchical Structure Design Enable Flexible Multipurpose Microwave Absorption and Infrared Stealth Compatibility

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Nano-Micro Letters 2025年第2期17卷 401-416页

作者： Chen Li Leilei Liang Baoshan Zhang Yi yang Guangbin Ji School of Electronic Science and Engineering Nanjing UniversityNanjing 210093People’s Republic of China College of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 210016People’s Republic of China

Developing advanced stealth devices to cope with radar-infrared(IR)fusion detection and diverse application scenarios is increasingly demanded,which faces significant challenges due to conflicting microwave and IR cloaking mechanisms and functional integration ***,we propose a multiscale hierarchical structure design,integrating wrinkled MXene IR shielding layer and flexible Fe_(3)O_(4)@C/PDMS microwave absorption *** top wrinkled MXene layer induces the intensive diffuse reflection effect,shielding IR radiation signals while allowing microwave to pass ***,the permeable microwaves are assimilated into the bottom Fe_(3)O_(4)@C/PDMS layer via strong magneto-electric *** theoretical and experimental optimization,the assembled stealth devices realize a near-perfect stealth capability in both X-band(8–12 GHz)and long-wave infrared(8–14μm)wavelength ***,it delivers a radar cross-section reduction of−20 dB m^(2),a large apparent temperature modulation range(ΔT=70℃),and a low average IR emissivity of ***,the optimal device demonstrates exceptional curved surface conformability,self-cleaning capability(contact angle≈129°),and abrasion resistance(recovery time≈5 s).This design strategy promotes the development of multispectral stealth technology and reinforces its applicability and durability in complex and hostile environments.

关键词： Microwave absorption Radar-infrared compatible stealth Wrinkled MXene Magneto-dielectric synergy Multifunction

A review of system modeling, assessment and operational optimization for integrated energy systems

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Science China(Information Sciences) 2021年第9期64卷 5-27页

作者： jun ZHAO long CHEN Yinan WANG Quanli LIU Key Laboratory of Intelligent Control and Optimization for Industrial Equipment (Dalian University of Technology) Ministry of Education School of Control Science and Engineering Dalian University of Technology Department of Aeronautics and Astronautics Stanford University

Building an efficient, safe, and sustainable energy system has been listed as one of the national energy development strategies in China. Through unified management and optimization for the processes of energy generation, transmission, conversion, and distribution, the integrated energy system(IES) can meet the diversified demands on energy with high efficiency and effectiveness, providing the basis to form a low-carbon sustainable social development mode. This research reviews the studies and issues of system modeling, assessment, and operational optimization on the IES. The ongoing problems that need further investigation are also presented. Besides, research of data-driven approaches on the IES will be discussed,based on which the future research directions are suggested here.

关键词： IES system modeling assessment operational optimization data-driven

Low-cost and fluoride-free synthesis of MFI zeolite nanosheets with enhanced stability for benzene alkylation with ethanol

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Journal of Energy Chemistry 2025年第1期100卷 458-468页

作者： Peng Zhu Cun Liu Yiren Yu Guoshu Gao Yumeng Zhao Xiongfu Zhang Guodong Liu Guohui yang State Key Laboratory of Fine Chemicals School of Chemical Engineering Dalian University of Technology State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences

Zeolite nanosheets with a short b-axis thickness are highly desirable in lots of catalytic reactions due to their reduced diffusion resistance. Nevertheless, conventional synthesis methods usually require expensive structure-directing agents(SDAs), pricey raw materials, and eco-unfriendly fluorine-containing additives. Here, we contributed a cost-effective and fluoride-free synthesis method for synthesizing high-quality MFI zeolite nanosheets through a Silicalite-1(Sil-1) seed suspension and urea cooperative strategy, only with inexpensive colloidal silica as the Si source. Our approach was effective for synthesizing both Sil-1 and aluminum-containing ZSM-5 nanosheets. By optimizing key synthesis parameters,including seed aging time, seed quantity, and urea concentration, we achieved precise control over the crystal face aspect ratio and b-axis thickness. We also revealed a non-classical oriented nanosheet growth mechanism, where Sil-1 seeds induced the formation of quasi-ordered precursor particles, and the(010)crystal planes of these particles facilitated urea adsorption, thereby promoting c-axis-oriented *** obtained ZSM-5 nanosheets exhibited exceptional catalytic performance in the benzene alkylation with ethanol, maintaining stability for over 500 h, which is 5 times longer than traditional ZSM-5 catalysts. Furthermore, large-scale production of ZSM-5 nanosheets was successfully carried out in a 3 L highpressure autoclave, yielding samples consistent with those from laboratory-scale synthesis. This work marks a significant step forward in the sustainable and efficient production of MFI nanosheets using inexpensive and environmentally friendly raw materials, offering the broad applicability in catalysis.

关键词： MFI zeolite ZSM-5 Nanosheets Scale-up synthesis Aromatic alkylation

An Adaptive Time-Domain Kalman Filtering Approach to Acoustic Feedback Cancellation for Hearing Aids

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Chinese Journal of Electronics 2020年第1期29卷 139-146页

作者： LU Caixia yang Feiran yang jun Key Laboratory of Noise and Vibration Research Institute of Acoustics of Chinese Academy of Science University of Chinese Academy of Science

The adaptive filtering approach has been widely used for acoustic feedback control in the hearing aids due to its excellent performance. The commonly used adaptive filtering algorithms employ a fixed step-size,which has to compromise between the initial convergence and the steady-state misalignment. Many variable stepsize adaptive algorithms have been proposed to handle this problem. In this paper, we propose a broadband Kalman filter to resolve this problem. The acoustic feedback path is modelled by a first-order Markov model,and the observation equation is constructed using more past data vector. A major issue in the hearing aids is the computational complexity. We thus present a simplified version to reduce the complexity, which bridges between the exact Kalman filter and the affine projection algorithm. The estimation of the process and measurement noise variance is discussed in detail. A two-feedbackpath model is adopted to improve the algorithm’s lack of re-convergence. Simulation results confirm the proposed algorithm clearly outperforms the other variable step-size adaptive filtering approaches.

关键词： Acoustic feedback cancellation Kalman filter Convergence rate Tracking capability

Femtosecond Laser Pulses for Drilling the Shaped Micro-Hole of Turbine Blades

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Chinese Physics Letters 2013年第4期30卷 77-80页

作者： JIA Hai-Ni yang Xiao-jun ZHAO Wei ZHAO Hua-long DU Xu yang Yong Xi'an Institute of Optics and Precision Mechanics Chinese Academy of SciencesXi'an 710119 National Time Service Center Chinese Academy of SciencesXi'an 710600

We design a set of processing devices to drill the shaped holes of turbine blades by using a femtosecond laser which outputs 1064 nm 5 W pulses at 100 kHz,investigate the mechanism of the femtosecond laser interaction with metals,and demonstrate that ultrafast laser drilling has distinct strong points against electric spark and longer laser pulse *** advantages related to no recast layer,no thermal effect,no micro crack,high precision,and high processing efficiency are carried out.

关键词： Femto Turbine Pulse

Two-step hydrothermal conversion of biomass waste to humic acid using hydrochar as intermediate

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Frontiers of Environmental Science & Engineering 2023年第10期17卷 17-26页

作者： Yuchao Shao jun Zhao Yuyang long Wenjing Lu School of Environment Tsinghua UniversityBeijing 100084China Department of Biology Institute of Bioresource and AgricultureHong Kong Baptist UniversityHong Kong 999077China Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling Instrumental Analysis CenterSchool of Environmental Science and EngineeringZhejiang Gongshang UniversityHangzhou 310012China

Converting biomass materials to humic acid is a sustainable method for humic acid production and achieve biomass valorization. A two-step hydrothermal treatment method was adopted in this study to produce humic acid from corn stalks. In the first step of the process, hydrochar was prepared at different hydrothermal temperatures and pH values. Their chemical properties were then analyzed, and the hydrochar-derived humic acids were produced under alkaline hydrothermal conditions (denoted as HHAalk). The hydrochar, prepared under high temperature (200 °C) and strong acidic (pH 0) conditions, achieved high HHAalk yields (i.e., 67.9 wt% and 68.8 wt% calculated based on weight of hydrochar). The sources of HHAalk formation were as follows: 1) production in the hydrochar preparation stage, and 2) increment under the alkaline hydrothermal treatment of hydrochar. The degree of hydrochar unsaturation was suggested as an indicator for evaluating the hydrochar humification potential under alkaline hydrothermal conditions. This study provides an important reference for the preparation of suitable hydrochar with high hydrothermal humification potential.

关键词： Biowaste Hydrochar Humic acid Hydrothermal parameter Unsaturation

Power law creep and relaxation with the atomic force microscope:Determining viscoelastic property of living cells

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Science China(Technological Sciences) 2019年第5期62卷 781-786页

作者： BU yang LI long WANG JiZeng Key Laboratory of Mechanics on Disaster and Environment in Western China Ministry of Education College of Civil Engineering and Mechanics Lanzhou University

We have proposed a method to determine the deformation creep and stress relaxation of living cells by using the atomic force microscope(AFM). Based on this method, we have measured the creep and relaxation trajectories of the undifferentiated(HGC-27) and poorly differentiated(AGS) human gastric cancer cells, which were then used to determine their linear viscoelastic properties. We found that the AGS cells are linear viscoelastic materials with the power law creep compliance and relaxation modulus. In contrast, the HGC-27 cells are nonlinear since their measured creep and relaxation behaviours fail to satisfy a verification relation derived based on the linear viscoelastic theory. This fact implies that most traditional methods are not appropriate in determining viscoelastic properties of living cells by simply assuming linear constitutive relation and using classical model of linear springs and dashpots. The combination of suggested power law expression and AFM indentation measurements on the creep compliance and relaxation modulus provides a unique way in determining the viscoelastic properties of living cells.

关键词： atomic force microscope linear viscoelasticity creep relaxation power law living cells

An explosive mud volcano origin for the pitted cones in southern Utopia Planitia,Mars

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Science China Earth Sciences 2023年第9期66卷 2045-2056页

作者： Le WANG Jiannan ZHAO jun HUANG long XIAO School of Earth Sciences China University of GeosciencesWuhan 430074China State Key Laboratory of Geological Processes and Mineral Resources Wuhan 430074China Key Laboratory of Geological Survey and Evaluation of Ministry of Education China University of GeosciencesWuhan 430074China

Pitted cones are cone-shaped structures,spanning from meters to kilometers in size,characterized by summit *** are widely distributed on the surface of Mars with various origins,such as rootless cones,mud volcanoes,cinder or scoria cones,tuff rings or cones,pingos,and dirt *** the pitted cones identified in southern Utopia Planitia are mud volcanoes,as is speculated,they could be of particular interest due to the fact that mud volcanoes on Earth bring sediments from a depth of meters to kilometers to the *** this study,we have investigated the pitted cones near Zhurong rover’s landing site in southern Utopia Planitia,utilizing recent images and digital elevation models obtained from the High Resolution Imaging Camera instrument onboard China’s Tianwen-1 *** leveraging the high-resolution images and digital elevation models,we have conducted a geometric measurement to distinguish the origin of pitted cones in the vicinity of the Zhurong *** morphological characteristics of these pitted cones indicate an explosive mud volcano *** explosive mud volcanoes could have formed by the violent eruption of subsurface overpressurized sediments generated from the combined effect of overburden pressure and anomalous high heat *** sediments forming the pitted cones in the northern plains could be the remnants of an ancient *** future in-situ observations of these pitted cones,we hope to gain further insights into the sediments of the putative northern ocean,as well as the physical and chemical properties of the Martian subsurface during the formation of the pitted cones.

关键词： Pitted cones Mud volcanoes Tianwen-l Mars

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Microglia Research in the 100th Year Since Its Discovery

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Neuroscience Bulletin 2020年第3期36卷 303-306页

作者： Anthony DUmpierre long-jun Wu Department of Neurology Mayo ClinicRochesterMN 55905USA Department of Neuroscience Mayo ClinicJacksonvilleFL 32224USA Department of Immunology Mayo ClinicRochesterMN 55905USA

In 1919,Pio del Rio-Hortega first described a class of cells residing in the brain with a tiny soma and branched architecture distinguishable from astrocytes and *** cells,called microglia or mesoglia,have come to be appreciated as resident immune cells in the central nervous system(CNS).In the year 2019,we review the three most recent advances in microglia research in this 100th year since their discovery(Fig.1).We first discuss their transcriptional diversity,which allows us to appreciate the heterogeneity of microglia across species,development,diseases,and brain *** also highlight recent stem cell-based approaches that allow us to study human microglia.

关键词： diseases glia appreciate