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Yolk-shell structured Co-C/Void/Co9S8 composites with a tunable cavity for ultrabroadband and efficient low- frequency microwave absorption

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Nano Research 2018年第8期11卷 4169-4182页

作者： Xiaofang Liu Chengcheng Hao lihua he Cheng Yang Yubin Chen Chengbao Jiang Ronghai Yu School of Materials Science and Engineering Beihang University Beijing 100191 China Beijing Institute of Aeronautical Materials Beijing 100095 China

A yolk-shell structured Co-C/Void/CogS8 ternary composite composed of a Co nanoparticle-embedded porous carbon core and Co9S8 shell was synthesized by the sulfidation of a Co-based zeolitic imidazolate framework and subsequent pyrolysis. The composition and interior cavity of the Co-C/Void/CogS8 composite could be precisely modulated by controlling the sulfidation reaction. Due to the abundant heterointerfaces, well-controlled cavity, and magnetic-dielectric synergistic effects, the Co-C/Void/CogS8 exhibited excellent and tunable microwave- absorbing properties. The optimized Co-C/Void/Cog~ having a loading of 25 wt.% and thickness only 2.2 mm, displayed an ultrabroad absorption bandwidth of 8.2 GHz at high frequencies. Moreover, the composite could achieve an extremely high reflection loss of -54.02 dB at low frequencies by adjusting its loading to 30 wt.%. This study provides a new insight into promising lightweight microwave-absorbing materials with ultrabroad absorption bandwidths and strong low-frequency absorption.

关键词： yolk-shell structure metal organic framework sulfide microwave absorption broad bandwidth

Study on Formaldehyde Gas Sensor Based on SnO_2 with La_2O_3-ZnO Doping

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稀有金属材料与工程 2006年第A03期35卷 129-131页

作者： Baofu Quan Fengmin Liu Ruzheng Liu lihua Chen Yuehua he Biao Wang College of Electronic Science and Engineering Jilin University Changchun 130012 China

SnO_2 nanpowder was prepared by sol-gel *** SnO_2 based formaldehyde sensor with the doping of La_2O_3 (5wt%)-ZnO(3wt%) was *** range of the detecting concentration for formaldehyde is from 10μg/g to 300μg/g at 140℃.The sensitivity (S=R_0/R_g) to 10μg/g formaldehyde is 2 and to 300μg/g formaldehyde is *** 0.4 nm molecule-sifter layer was coated on the surface of SnO_2 material,the result shows that the selectivity of the formaldehyde sensor is improved. The La_2O_3-ZnO doped SnO_2 sensor shows better stability during 60 days testing.

关键词： SnO2 formaldehyde sensitivity selectivity

Single source precursor derived SiBCNHf ceramic with enhanced high-temperature microwave absorption and antioxidation

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Journal of Materials Science & Technology 2022年第31期126卷 215-227页

作者： Yan Song Ziyu Liu Xicheng Zhang Runqiu Zhu Youwei Zhang Pinggui Liu lihua he Jie Kong MOE Key Laboratory of Space Applied Physics and Chemistry School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’an 710072China AECC Beijing Institute of Aeronautical Materials Beijing 100095China

Electromagnetic(EM)wave-absorbing materials with high-temperature-resistance are urgently desirable to eliminate EM interference in extreme *** derived ceramics(PDC)route is being evolved as an effective strategy to solve the ***,a single source hyperbranched polyborosi-lazane precursor containing hafnium(hb-PBSZ-Hf)is introduced and the SiBCNHf ceramic is obtained by further *** micro-sized tissues including HfC,SiC,HfB 2 nanocrystals and segregated carbons are in situ generated during annealing which not only increase EM wave absorption ability(minimum re-flection coefficient(RC_(min))is-56.71 dB with a thickness of 2.5 mm,effective absorption bandwidth(EAB)is 3.4 GHz),but also improve antioxidation property(less than 2 wt.%mass fluctuation at 1400℃in air).Theoretical simulation of complex permittivity suggests that SiBCNHf ceramic has an RC_(min)of less than-5 dB for the whole X-band even at 1100℃.Such SiBCNHf ceramic with superior high-temperature-resistance and antioxidation performance derived from single source precursors possesses great potential for EM wave absorbing coatings in high-temperature and harsh environments.

关键词： hb-PBSZ-Hf precursor SiBCNHf ceramic EM wave absorption Antioxidation performance

African Swine Fever Virus MGF360-12L Inhibits Type Ⅰ Interferon Production by Blocking the Interaction of Importin α and NF-κB Signaling Pathway

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Virologica Sinica 2021年第2期36卷 176-186页

作者： Yisha Zhuo Zeheng Guo Tongtong Ba Cheng Zhang lihua he Cuiping Zeng Hanchuan Dai College of Veterinary Medicine Huazhong Agricultural UniversityWuhan 430070China

African swine fever(ASF)is an infectious transboundary disease of domestic pigs and wild boar and spreading throughout *** is no vaccine and treatment *** immune escape strategies of African swine fever virus(ASFV)are crucial factors affecting immune prevention and vaccine ***360 genes have been implicated in the modulation of the IFN-Ⅰ*** molecular mechanisms contributing to innate immunity are poorly *** this study,we demonstrated that ASFV MGF360-12 L(MGF360 families 12 L protein)significantly inhibited the mRNA transcription and promoter activity of IFN-βand NF-κB,accompanied by decreases of IRF3,STING,TBK1,ISG54,ISG56 and AP-1 m RNA ***,MGF360-12 L might suppress the nuclear localization of p50 and p65 mediated by classical nuclear localization signal(NLS).Additionally,MGF360-12 L could interact with KPNA2,KPNA3,and KPNA4,which interrupted the interaction between p65 and KPNA2,KPNA3,*** further found that MGF360-12 L could interfere with the NF-κB nuclear translocation by competitively inhibiting the interaction between NF-κB and nuclear transport *** findings suggested that MGF360-12 L could inhibit the IFN-Ⅰproduction by blocking the interaction of importinαand NF-κB signaling pathway,which might reveal a novel strategy for ASFV to escape the host innate immune response.

关键词： African swine fever virus(ASFV) MGF360-12L IFN-Ⅰ NF-κB Nuclear transport

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Microstructure and Mechanical Properties of Aer Met 100 Ultra-high Strength Steel Joints by Laser Welding

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Journal of Wuhan University of Technology(Materials Science) 2015年第4期30卷 827-830页

作者：刘奋成 YU Xiaobin HUANG Chunping he lihua CheN Yuhua BU Wende National Defence Key Discipline Laboratory of Light Alloy Processing Science and Technology Nanchang Hangkong University

AerMet100 ultra-high strength steel plates with a thickness of 2 mm were welded using a COz laser welding system. The influences of the welding process parameters on the morphology and microstructure of the welding joints were investigated, and the mechanical property of the welding joints was analyzed. The experimental results showed that the fusion zone of welding joint mainly consisted of columnar grains and a fine dendrite substructure grew epitaxially from the matrix. With the other conditions remaining unchanged, a finer weld microstructure was along with the scanning speed increase. The solidification microstructure gradually transformed from cellular crystal into dendrite crystal and the spaces of dendrite secondary arms rose from the fusion line to the center of the fusion zone. In the fusion zone of the weld, the rapid cooling caused the formation of martensite, which led the microhardness of the fusion zone higher than that of the matrix and the heat affected zone. The tensile strength of the welding joints was tested as 1 700 MPa, which was about 87% of the matrix. However, the tensile strength of the welding joints without defects existed was tested as 1832 MPa, which was about 94% of the matrix.

关键词： laser welding AerMet 100 ultra-high strength steel microstructure mechanical property

Flexible multi-level quasi-volatile memory based on organic vertical transistor

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Nano Research 2022年第1期15卷 386-394页

作者： Huihuang Yang Qian Yang lihua he Xiaomin Wu Changsong Gao Xianghong Zhang Liuting Shan Huipeng Chen Tailiang Guo Institute of Optoelectronic Display National&Local United Engineering Lab of Flat Panel Display TechnologyFuzhou UniversityFuzhou 350002China Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou 350100China Zhicheng College Fuzhou UniversityFuzhou 350002China

Driven by important megatrends such as cloud computing,artificial intelligence,and the Internet of Things,as a device used to store programs and data in computing systems,memory is struggling to catch up with the explosive growth of data and bandwidth requirements in the ***,the storage wair between non-volatile memory and volatile memory retards the further improvement of modern memory computing ***,a quasi-volatile transistor memory based on organic polymer/perovskite quantum dot blend was fabricated using the vertical transistor *** to vertical structure and appropriate doping ratio of blend film,the quasi-volatile memory device displayed 1,560 times longer data retention time(>100 s)with respect to the dynamic random access memory and fast data programming speed(20 ps)in which was far more quickly than that of other organic non-volatile memories to fill the gap between volatile and non-volatile ***,the device retention characteristics could be further promoted under the photoelectric synergistic stimulation,which also provided the possibility to reduce electric writing ***,the quasi-volatile memory device showed good electrical performance under bending *** work provides a simple solution to fabricate multi-level quasi-volatile memory,which opens up a whole new avenue of"universal memory"and lays a solid foundation for low power and flexible random access memory devices.

关键词： vertical transistor organic transistor memory perovskite quantum dot quasi-volatile memory storage wall

Oxygen-rich carbon-nitrogen quantum dots as cocatalysts for enhanced photocatalytic H2 production activity of TiO2 nanofibers

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Progress in Natural Science:Materials International 2017年第3期27卷 333-337页

作者： Zhiyan Chen Yishang Wu Qichen Wang Zhiyong Wang lihua he Yongpeng Lei Zhongmin Wang School of Materials Science and Engineering Central South University of Forestry and Technology AVIC Beijing Institute of Aeronautical Materials College of Basic Education National University of Defense Technology School of Aeronautics and Astronautics Central South University Guangxi Key Laboratory of Information Materials Guilin University of Electronic Technology

We developed an one-step hydrothermal method to synthesize carbon-nitrogen quantum dots（CNQDs） with oxygen-rich functional *** sample was characterized by TEM,AFM,FT-IR,XPS,UV-vis absorption and PL *** 0/C and N/C atomic ratio of typical CNQDs with diameters of 3-6 nm are ca.0.4 and 0.2,*** noble metal cocatalyst,the photocatalytic H2production rate of CNQDs/TiO2nanofibers（NFs）(112.4 μmol h-1g-1) is 1.8 times higher than that of *** good absorption of light contributes to the enhanced photocatalytic *** CNQDs could be promising in biomedical imaging,optical data recording storage and photo/electrocatalysis,etc.

关键词： Photocatalytic H2 production TiO2 Nanofibers Quantum dots

Emissive Mononuclear Cu（Ⅰ） Triphenylphosphine Complexes with Functionalized 6-tert-Butoxycarbonyl-2,2 ＇-bipyridine

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Chemical Research in Chinese Universities 2018年第1期34卷 19-23页

作者： LUO Yansheng ZENG Xuehua WANG Wanman CheN Jinglin he lihua ZHANG Mengli LIU Suijun WEN herui School of Metallurgy and Chemical Engineering Jiangxi University of Science and Technology Ganzhou 341000 P. R. China

Two new emissive mononuclear copper（Ⅰ） triphenylphosphine complexes with functionalized 6-tert- butoxycarbonyl-2,2＇-bipyridiue chelating ligands were prepared and characterized. Each Cu（Ⅰ） cation has a markedly distorted P2N2 tetrahedral array with two different Cu--N bond distances, due to the addition of the bulky tert-butoxycarbonyl group at the 6-position of the 2,2＇-bipyridyl ring. A weak low-energy broad absorption band appears at 330-500 nm in their CH2Cl2 solutions, which is influenced by the methylation of the 2,2＇-bipyridyl ring. At room temperature, the photoluminescence can be clearly observed both in degassed CH2Cl2 solution and in the solid state, because of the introduction of the bulky tert-butoxycarbonyl substituent, and the emission properties are remarkably affected by both the methylation and the alkoxycarbonyl variation of the 2,2＇-bipyridyl ring. It is shown that the introduction of the bulky tert-butoxyearbonyl group is favorable for improving the emission properties of the 6-alkoxycarbonyl-2,2＇-bipyridine-based cuprous complexes.

关键词： Cuprous Methylation Alkoxyearbonyl Phosphine Lnminescence

Primary Breeding Ratio Analysis of an Improved Supercritical Water Cooled Fast Reactor

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World Journal of Nuclear Science and Technology 2015年第4期5卷 253-264页

作者： Zijing Liu Jinsen Xie lihua he Department of Nuclear Science and Technology University of South China Hengyang China China Institute of Atomic Energy Beijing China

The purpose of the study is to analyze the breeding ratio of a supercritical water cooled fast reactor (SCFR) and to increase the breeding core of SCFR. The sensitivities of assembly parameters, core arrangements and fuel nuclide components to the breeding ratio are analyzed. In assembly parameters, the seed fuel rod diameter has higher sensitivities to the conversion ratio (CR) than the coolant tube diameter in blanket. Increasing heavy metal fraction is good to CR improvement. The CR of SCFR also increases with a reasonable core arrangement and Pu isotope mass fraction reduction in fuel, which can achieve more negative coolant void reactivity coefficient at the same time. The breeding ratio of SCFR is 1.03128 with a new core arrangement. And the coolant void reactivity coefficient is negative, which achieves a fuel breeding in initial fuel cycle.

关键词： Supercritical Water Cooled Fast Reactor Breeding Ratio Coolant Void Coefficient