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Defence Technology（防务技术） 2023年第4期22卷 74-87页

作者： Yong Kou yi Wang Jun Zhang Kai-ge Guo Xiao-lan Song School of Environment and Safety Engineering North University of ChinaTaiyuanShanxi030051China School of Materials Science and Engineering North University of ChinaTaiyuanShanxi030051China School of Ordance Engineering Naval University of EngineeringWuhanHubei430033China School of Chemical Engineering Nanjing University of Science and TechnologyNanjingJiangsu210094China

Aluminum(Al)powder is widely used in solid *** particular,nano-Al has attracted extensive scholarly attention in the field of energetic materials due to its higher reactivity than ***,the existence of aluminum oxide film on its surface reduces the heat release performance of the aluminum powder,which greatly limits its ***,this paper used iron,a component of solid propellant,to coat micron-Al and nano-Al to improve the heat release efficiency and reactivity of Al ***,TEM,EDS,XRD,XPS,and BET were used to investigate the morphological structure and properties of pure Al and Fe/Al composite fuels of different *** results show that Fe was uniformly coated on the surface of Al *** was no reaction between Fe and Al,and Fe/Al composite fuels had a larger specific surface area than pure Al,which could better improve the reactivity of pure ***,the catalytic effects of pure Al and Fe/Al composite fuels of different sizes on ammonium perchlorate and ammonium nitrate were *** results show that the catalysis of pure Al powder could be greatly improved by coating Fe on the surface of Al ***,the micron-Fe/Al composite fuel had a higher catalytic effect than the pure nano-Al ***,Fe/Al composite fuels are expected to be widely used in solid propellants.

关键词： Aluminum Fe/Al composite fuel High reactivity Thermal decomposition AP AN

Influences of meridional flowpath on the performance of swept blade in an axial compressor stage

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航空动力学报 2015年第8期30卷 1875-1887页

作者： YU Xian-jun XU Peng-fei ZHANG yi-fei LIU Bao-jie School of Energy and Power Engineering Beiiing University of Aeronautics and Astronautics Beijing 100191 China National Key Laboratory of Science and Technology on Aero-Engine Aero-thermodynamics School of Energy and Power EngineeringBeijing University of Aeronautics and Astronautics Beijing 100191 China Collaborative Innovation Center for Advanced Aero-Engine Beijing 100191 China

A series of numerical simulations were conducted in both a 1.5stage axial compressor model and a simplified planar cascade *** cases with different blade sweep schemes in the cascade model were simulated with free-slip endwalls to minimize the influence of endwall 3-D(three-dimensional)*** results obtained in the cascade model were discussed at first for getting a clear insight into the effects of blade sweep without other *** then the simulation results of the 1.5stage compressor model were discussed *** discussions focused on the influences of different meridional flowpath designs,*** mid radius(CMR)design,constant outer radius(COR)design and constant inner radius(CIR)design,on the performance of the swept *** results showed that the most critical effect produced by blade sweep was attributed to the redistribution of local mass-flow-rate in blade spanwise *** change of meridional flowpath did not change the mass-flow-rate redistribution ***,the trends for local mass-flow-rate redistribution in compressor stage model showed some discrepancies compared with the results shown in the planar cascade model.

关键词：航空航空动力学航空发动机发动原理

Scallop ice shape characteristics of swept wing based on large-scale icing wind tunnel experiment

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Chinese Journal of Aeronautics 2023年第12期36卷 214-230页

作者： Qiang WANG Ningli CHEN Yuanbo WANG Weihao LI Yu LIU Xian yi Low Speed Aerodynamics Institute China Aerodynamics Research and Development CenterMianyang 621000China Anti/de-icing Key Laboratory of China Aerodynamics Research and Development Center Mianyang 621000China Key Laboratory of Aerodynamics Mianyang 621000China Design and Research Institute of AVIC Shaanxi Aircraft Industry Group Hanzhong 723000China

Scallop ice is a special phenomenon that occurs during swept wing aircraft passing through icing *** poses a great challenge for the icing safety assessment that the complex scallop ice shape feature and its mechanism are still *** this work,a large-scale icing wind tunnel experiment of swept wing designed by NACA0012 airfoil is conducted in the Icing Wind Tunnel of China Aerodynamics Research and Development *** detailed three-dimensional ice shapes under 0°,15°,30°and 45°swept angles are obtained by laser scanning *** experimental results show that with the swept angle increasing from 0°to 45°,the 2D double ice horn structures show certain spanwise variation,and finally transform into complete scallop ice with ice thickness greatly enhanced in the stagnation line *** empirical mode decomposition of the spanwise ice curve captures the high-frequency fluctuation on the scallop ice caused by the small-scale roughness element,while the trend with low frequency is not *** on the experimental data,a new complete scallop ice geometric model,named 5Points-5Lines-2Arcs(5P-5L-2A)model,is proposed,which can provide important basis for the quantitative description of complex scallop ice shape.

关键词： Aircraft Swept wings Scallop ice Icing wind tunnel experi-ment Scallop ice geometric model

MOFs derived magnetic porous carbon microspheres constructed by core-shell Ni@C with high-performance microwave absorption

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Journal of Materials Science & Technology 2021年第29期88卷 56-65页

作者： Sai Gao Guozheng Zhang yi Wang Xiaopeng Han ying Huang Panbo Liu School of Chemistry and Chemical Engineering Northwestern Polytechnical UniversityXi’an710129China

Lightweight and high-performance are two determining factors for metal-organic-frameworks(MOFs)derived microwave ***,most of the reported MOFs derived absorbers usually possess high filler ***,a series of MOFs derived magnetic porous carbon microspheres with tunable diameter and high specific surface area have been synthesized via a pyrolysis *** synthesized magnetic porous carbon microspheres,constructed by uniformly distributed core-shell Ni@C,exhibit high-performance microwave absorption with a low filler loading of 10 wt%.Considering the mciro-mesoporous structures,matched impedance,strong conductive loss,enhanced dipolar/interfacial polarization as well as strong magnetic coupling network,a minimum reflection loss of-60 dB and an absorption bandwidth of 7.0 GHz can be achieved at 2.6 ***,the bandwidth reaches as wide as 10.2 GHz when the thickness is 4 *** addition,compared with other MOFs derived absorbers,this work provides us a simple strategy for the synthesis of porous carbon microspheres with lightweight and high-performance microwave absorption for practical applications.

关键词： Metal-organic-frameworks Carbon microspheres Magnetic particles Core-shell structure Microwave absorption

Analysis method and experimental study of ice accumulation detection signal based on Lamb waves

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Chinese Journal of Aeronautics 2024年第8期37卷 388-403页

作者： Yanxin ZHANG Hongjian ZHANG Xian yi Binrui WU Xianlei GUAN Jianjun XIONG Key Laboratory of Icing and Anti/De-icing China Aerodynamics Research and Development CenterMianyang 621000China State Key Laboratory of Aerodynamics China Aerodynamics Research and Development CenterMianyang 621000China

A quantitative identification method for in-flight icing has the capability to significantly enhance the safety of aircraft *** guided waves have the unique advantage of detecting icing in a relatively large area,but quantitative identification of ice layers is a *** this paper,a quantitative identification method of ice accumulation based on ultrasonic guided waves is ***,a simulation model for the wave dynamics of piezoelectric coupling in three dimensions is established to analyze the propagation characteristics of Lamb waves in a structure consisting of an aluminum plate and an ice *** wavelet transform method is utilized to extract the Time of Flight(ToF)or Time of Delay(ToD)of S_(0)/B_(1) mode waves,which serves as a characteristic parameter to precisely determine and assess the level of ice ***,an experimental system is developed to evaluate the feasibility of Lamb waves-based icing real-time detection in the presence of spray ***,a combination of the Hampel median filter and the moving average filter is developed to analyze ToF/ToD *** simulation results reveal a positive correlation between geometric dimensions(length,width,thickness)of the ice layer and ToF/ToD of B1 mode waves,indicating their potential as indicators for quantifying ice *** results of real-time icing detection indicate that ToF/ToD will reach greater peak values with the growth of the arbitrary-shaped ice layer until saturation to effectively predict the simulation *** study lays a foundation for the practical application of quantitative icing detection via ultrasonic guided waves.

关键词： Ice Ice accumulation Ultrasonic sensor Ultrasonic guided wave Lamb wave Wavelet transform

Experimental investigation of expansion effect on shock wave boundary layer interaction near a compression ramp

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Chinese Journal of Aeronautics 2022年第12期35卷 89-101页

作者： Junjie HUO Shihe yi Wenpeng ZHENG Haibo NIU Xiaoge LU Dundian GANG College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China

The experiment is conducted to investigate the effect of expansion on the shock wave boundary layer interaction near a compression ramp. The small-angle expansion with an angle degree of 5° occurs at different positions in front of the compression ramp. The particle image velocimetry and flow visualization technology show the flow structures, velocity field, and velocity fluctuation near the compression ramp. The mean pressure distribution, pressure fluctuation, and power spectral density are measured by high-frequency response pressure transducers. The experimental results indicate that the expansion before the compression ramp position affects the shock wave boundary layer interaction to induce a large-scale separation. But the velocity fluctuation and pressure fluctuation are attenuated near the large-scale flow separation region. When the expansion occurs closer to the compression ramp, the expansion has a more significant impact on the flow. The fluctuation of velocity and pressure is significantly attenuated, and the wall pressure rise of the separation point is reduced obviously. And the characteristic low-frequency spectrum signal related to the unsteadiness of the shock wave boundary layer interaction is significantly suppressed. In addition, variation of the separation region scale at different compression angle degrees is distinctive with the effect of expansion.

关键词： Boundary layers Flow visualization Fluid dynamic Pressure measurement Shock waves Supersonic aerodynamics Velocity measurement

Highly coordinated Pd overlayers on nanoporous gold for efficient formic acid electro-oxidation

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Nano Research 2021年第10期14卷 3502-3508页

作者： Qinqin Sang Shuai yin Feng Liu Huiming yin Jia He yi Ding Tianjin Key Laboratory of Advanced Functional Porous Materials Institute for New Energy Materials&Low-Carbon TechnologiesSchool of Materials Science and EngineeringTianjin University of TechnologyTianjin 300384China Kunming Institute of Precious Metals Kunming 650106China

Design and fabrication of highly efficient and stable electrocatalysts remain key challenges in green energy technologies such as low-temperature direct liquid fuel *** on in-depth theoretical calculations,here we demonstrate that surface Pd atoms with high coordination numbers(HCNs)can effectively modulate their adsorption energies for CO and OH,and thus achieve very high performance for formic acid electro-oxidation reaction(FAOR).Based on epitaxial coating Pd atomic layers onto nanoporous gold(NPG)thin membranes and a slight further decoration of Au clusters on top,the resulted core-shell structured NPG-Pd-Au electrocatalyst can demonstrate Pd intrinsic and mass activities of 8.62 mA·cm^(-2)and 27.25 A·mg^(-1)respectively at the peak potential around 0.33 V versus saturated calomel electrode toward FAOR,which are far better than those of commercial Pd/C catalysts(1.09 mA·cm^(-2)and 0.32 A·mg^(-1))tested under the same ***,the membrane electrode assemblies based on these low precious metal loading electrodes can achieve an anode Pd power efficiency over 10 W·mg^(-1)in a direct formic acid fuel cell,which is two orders of magnitude higher than that of the commercial Pd/*** results provide new inspirations for the development of revolutionary electrodes for energy technologies in a rational manner.

关键词： Pd nanoporous gold high coordination number formic acid oxidation direct formic acid fuel cell

Experimental realization of nonadiabatic geometric gates with a superconducting Xmon qubit

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Science China(Physics,Mechanics & Astronomy) 2021年第5期64卷 2-9页

作者： PeiZi Zhao ZhangJingZi Dong ZhenXing Zhang GuoPing Guo DianMin Tong yi yin Deparment of Physies Shandong Universiry Jinan 250100 China Department of Physics Zhejiang UniversityHangzhou 310027China Key Labortlory of Quanwum Information University of Science and Technology of ChinaHefei 230026China Origin Quantum Computing Hefei 230026China

Geometric phases are only dependent on evolution paths but independent of evolution details so that they possess some intrinsic noise-resilience features. Based on different geometric phases, various quantum gates have been proposed, such as nonadiabatic geometric gates based on nonadiabatic Abelian geometric phases and nonadiabatic holonomic gates based on nonadiabatic nonAbelian geometric phases. Up to now, nonadiabatic holonomic one-qubit gates have been experimentally demonstrated with superconducting transmons, where the three lowest levels are all utilized in operation. However, the second excited state of transmons has a relatively short coherence time, which results in a decreased fidelity of quantum gates. Here, we experimentally realize Abelian-geometric-phase-based nonadiabatic geometric one-qubit gates with a superconducting Xmon qubit. The realization is performed on the two lowest levels of an Xmon qubit and thus avoids the influence from the short coherence time of the second excited state. The experimental result indicates that the average fidelities of single-qubit gates can be up to 99.6% and 99.7% characterized by quantum process tomography and randomized benchmarking.

关键词： geometric phases geometric quantum computation superconducting qubit

Invasion, expansion, and control of Bactrocera dorsalis(Hendel) in China

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Journal of Integrative Agriculture 2019年第4期18卷 771-787页

作者： LIU Huan ZHANG Dong-ju XU yi-juan WANG Lei CHENG Dai-feng QI yi-xiang ZENG Ling LU Yong-yue Department of Entomology South China Agricultural University

The Oriental fruit fly, Bactrocera dorsalis(Hendel), is among the most destructive fruit/vegetable-eating agricultural pests in the world, particularly in Asian countries such as China. Because of its widespread distribution, invasive ability, pest status, and economic losses to fruit and vegetable crops, this insect species is viewed as an organism warranting severe quarantine restrictions by many countries in the world. To understand the characteristics and potential for expansion of this pest, this article assembled current knowledge on the occurrence and comprehensive control of the Oriental fruit fly in China concerning the following key aspects: invasion and expansion process, biological and ecological characteristics, dynamic monitoring, chemical ecology, function of symbionts, mechanism of insecticide resistance, control index, and comprehensive control and countermeasures. Some suggestions for the further control and study of this pest are also proposed.

关键词： Oriental fruit fly invasion biology ecology management China

Sphingosine kinase 1 knockout alleviates hepatic ischemia/reperfusion injury by attenuating inflammation and oxidative stress in mice

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Hepatobiliary & Pancreatic Diseases International 2019年第3期18卷 255-265页

作者： Guang-Hui Qiang Zhong-Xia Wang An-Lai Ji Jun-yi Wu yin Cao Guang Zhang yi-Yang Zhang Chun-Ping Jiang Department of Hepatobiliary Surgery Nanjing Drum Tower Hospital Drum Tower Clinical College of Nanjing Medical University Nanjing 210008 China Department of Hepatobiliary Surgery the Affiliated Drum Tower Hospital of Nanjing University Medical School Nanjing 210008 China Department of Gastroenterology Nanjing Drum Tower Hospital Drum Tower Clinical College of Nanjing Medical University Nanjing 210008 China

Background: Hepatic ischemia/reperfusion(I/R) injury remains a significant problem in clinical practice. Sphingosine kinase 1(Sph K1) phosphorylates sphingosine to sphingosine-1-phosphate(S1 P) which participates in multiple bioactive processes. However, little is known about the role of Sph K1 in hepatic I/R injury. This study aimed to investigate the effect of Sph K1 knockout on liver I/R injury and to explore underlying mechanisms. Methods: Sph K1 knockout and wild type mice were subjected to 70% partial hepatic I/R. Serum alanine aminotransferase was determined to indicate the degree of liver damage. Hematoxylin-eosin staining and TUNEL assay were used to assess histological changes and hepatocellular apoptosis, respectively. Immunohistochemistry was performed to detect the expression and translocation of phosphorylated p65 and signal transducer and activator of transcription 3(STAT3). Western blotting was used to determine the expression of S1 P receptor 1(S1 PR1), phosphorylated p65 and STAT3. Real-time PCR was used to demonstrate the changes of proinflammatory cytokines. Oxidative stress markers were also determined through biochemical assays. Results: Sph K1 knockout significantly ameliorated I/R-induced liver damage, mitigated liver tissue necrosis and apoptosis compared with wild type control. I/R associated inflammation was alleviated in Sph K1 knockout mice as demonstrated by attenuated expression of S1 PR1 and reduced phosphorylation of nuclear factor kappa B p65 and STAT3. The proinflammatory cytokines interleukin-1 β, interleukin-6 and tumor necrosis factor-α were also inhibited by Sph K1 genetic deletion. The oxidative stress markers were lower in Sph K1 knockout mice after I/R injury than wild type mice. Conclusions: Knockout of Sph K1 significantly alleviated damage after hepatic I/R injury, possibly through inhibiting inflammation and oxidative stress. Sph K1 may be a novel and potent target in clinical practice in I/R-related liver injury.

关键词： Ischemia/reperfusion injury Sphingosine kinase 1 Inflammation Oxidative stress