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Overlapped frequency-time division multiplexing

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The Journal of China Universities of Posts and Telecommunications 2009年第2期16卷 8-13页

作者： jiang hui LI Dao-ben School of Information Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

A technique named overlapped frequency-time division multiplexing （OVFTDM）） is proposed in this article. The technique is derived from Nyquist system and frequency-time division multiplexing system. When the signals are compactly overlapped without the orthogonality in time domain, the technique is named overlapped time division multiplexing （OVTDM）, whereas when signals are compactly overlapped without the orthogonality in frequency domain, the technique is called overlapped frequency division multiplexing （OVFDM）. To further improve spectral efficiency, the OVFTDM in which signals are overlapped both in frequency domain and in time domain is explored. OVFTDM does not depend on orthogonality whatever in time domain or in frequency domain like Nyquist system or OFDM system, but on the convolutional constraint relationship among signals. Therefore, not only the spectral efficiency but also the reliability is improved. The simulations verify the validity of this theory.

关键词： overlap OVFTDM spectral efficiency

Revisit of Dynamical Mechanisms of Transporting Asteroids in the 3:1 Resonance to the Near-Earth Space

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Chinese Journal of Astronomy and Astrophysics 2007年第1期7卷 148-154页

作者： jiang-hui Ji Lin Liu Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 Department of Astronomy Nanjing University Nanjing 210093 National Astronomical Observatories Chinese Academy of Sciences Beijing 100012

It is well-known that the asteroids in the main belt trapped in the 3：1 Mean Motion Resonance （MMR） with Jupiter （at semi-major axes -2.5 AU） are few in number, forming one of the so-called Kirkwood Gaps. Wisdom pointed out that chaotic motion of such aster- oids can increase their eccentricities and make them approach and cross the orbit of Mars （or even the Earth）. We numerically investigated the orbital evolution of the asteroids involved in 3：1 MMR （NEOs） over millions of years and revisited the dynamical mechanisms of trasporitng such asteroids into the NEO region. The results show that the dynamical evolution of the asteroids around 2.5 AU is mainly dominated by the 3：1 resonance, the v5 and v6 secular resonances and the Kozai resonance, and these bodies can evolve into NEOs through several of the dynamical mechanisms, so indicating possible dynamical origin of the NEOs.

关键词： celestial mechanics-near-Earth Objects-mean motion resonance-secular resonance

Microanalysis on the Hydrogen Ion Irradiated 50 wt pct TiC-C Films

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Journal of Materials Science & Technology 2007年第1期23卷 127-130页

作者： hui jiang Yaoguang LIU Ningkang HUANG Key Laboratory for Radiation Physics and Technology of Education Ministry of China Institute of Nuclear Science and Technology Sichuan University Chengdu 610064 China Institute of Nuclear Physics and Chemistry China Academy of Engineering Physics Mianyang 621900 China

The 50 wt pct TiC-C films were prepared on stainless steel substrates by using a technique of ion beam mixing. These films were irradiated by hydrogen ion beam with a dose of 1×10^18 ions/cm^2 and an energy of 5 keV. Microanalysis of X-ray photoelectron spectroscopy （XPS） and secondary ion mass spectroscopy （SIMS） were used to analyze the films before and after hydrogen ion irradiation and to study the mechanism of hydrogen resistance.

关键词： Titanium carbide Hydrogen ion irradiation Microanalysis

Endothelial cell metabolism in sepsis

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World Journal of Emergency Medicine 2023年第1期14卷 10-16页

作者： Jue-xian Wei hui-lin jiang Xiao-hui Chen Emergency Department the Second Affiliated HospitalGuangzhou Medical UniversityGuangzhou 510260China

BACKGROUND:Endothelial dysfunction in sepsis is a pathophysiological feature of septic organ *** cells(ECs)exhibit specific metabolic traits and release metabolites to adapt to the septic state in the blood to maintain vascular ***:Web of Science and PubMed were searched from inception to October 1,*** search was limited to the English language *** reviewers independently identified studies related to EC metabolism in *** exclusion criteria were duplicate articles according to multiple search ***:Sixty articles were included,and most of them were cell and animal *** studies reported the role of glycolysis,oxidative phosphorylation,fatty acid metabolism,and amino acid metabolism in EC *** glycolysis,oxidative phosphorylation,fatty acid metabolism and amino acid ***,dysregulation of EC metabolism can contribute to sepsis ***:There are few clinical studies on EC metabolism in *** research mainly focuses on basic research,but some scientific problems have also been ***,this review may provide an overall comprehension and novel aspects of EC metabolism in sepsis.

关键词： Sepsis Endothelium Metabolism Glycolysis Oxidative phosphorylation Fatty acid metabolism Amino acid metabolism

Facet-dependent antibacterial activity of Au nanocrystals

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Chinese Chemical Letters 2020年第12期31卷 3183-3189页

作者： Youkun Zheng hui jiang Xuemei Wang State Key Laboratory of Bioelectronics School of Biological Science and Medical EngineeringSoutheast UniversityNanjing 210096China Drug Discovery Research Center Key Laboratory of Medical Electrophysiology of Ministry of EducationSouthwest Medical UniversityLuzhou 646000China

Engineered nanomaterials have attracted significantly attention as one of the most promising antimicrobial agents for against multidrug resistant *** toxicological responses of nano mate rials are closely related to their physicochemical properties,and establishment of a structure-activity relationship for nanomaterials at the nano-bio interface is of great significance for deep understanding antibacterial toxicity mechanisms of nanomaterials and designing safer antibacterial *** this study,the antibacterial behaviors of well-defined crystallographic facets of a series of Au nanocrystals,including{100}-facet cubes,{110}-facet rhombic dodecahedra,{111}-facet octahedra,{221}-facet trisoctahedra and{720}-facet concave cubes,was investigated,using the model bacteria Staphylococcus *** find that Au nanocrystals display substantial facet-dependent antibacterial *** low-index facets of cubes,octahedra,and rhombic dodecahedra show considerable antibacterial activity,whereas the high-index facets of trisoctahedra and concave cubes remained inert under biological *** result is in stark contrast to the previous paradigm that the high-index facets were considered to have higher bioactivity as compared with low-index *** antibacterial mechanism studies have shown that the facet-dependent antibacterial behaviors of Au nanocrystals are mainly caused by differential bacterial membrane damage as well as inhibition of cellular enzymatic activity and energy *** faceted Au nanocrystals are unique in that they do not induce generation of reactive oxygen species,as validated for most antibiotics and antimicrobial *** findings may provide a deeper understanding of facet-dependent toxicological responses and suggest the complexities of the na no material-cell interactions,shedding some light on the development of high performance Au nanomaterials-based antibacterial therapeutics.

关键词： Au nanocrystals Facets Antibacterial activity Structure-activity relationship Toxicological response

Anomalous microstructure and tribological evaluation of AlCrFeNiW_(0.2)Ti_(0.5)high-entropy alloy coating manufactured by laser cladding in seawater

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Journal of Materials Science & Technology 2021年第26期85卷 224-234页

作者： hui Liang Dongxu Qiao Junwei Miao Zhiqiang Cao hui jiang Tongmin Wang Materials Science and Engineering Dalian University of TechnologyDalian116024China New Materials Innovation Center Ningbo Institute of Dalian University of TechnologyNingbo315000China College of Mechanical and Electronic Engineering Shandong University of Science and TechnologyQingdao266590China

To evaluate the potential of high entropy alloys for marine applications,a new high entropy alloy coating of AlCrFeNiW_(0.2)Ti_(0.5)was designed and produced on Q235 steel via laser *** microstructure,microhardness and tribological performances sliding against YG6 cemented carbide,GCr15 steel and Si_(3)N_(4)ceramic in seawater were studied in *** AlCrFeNiW_(0.2)Ti_(0.5)coating showed an anomalous’sunflower-like’morphology and consisted of BCC and ordered B2 *** microhardness was approximately 692.5 HV,which was 5 times higher than *** coating showed more excellent tribological performances than Q235 steel and SUS304,a typical material used in seawater environment,sliding against all three coupled balls in ***,the wear and friction of AlCrFeNiW_(0.2)Ti_(0.5)coating sliding against YG6 in seawater were most *** main reason was the generation of Mg(OH)_(2),CaCO_(3),metal oxides and hydroxides and the formation of protective tribo-film on the worn surface of AlCrFeNiW_(0.2)Ti_(0.5)coating in the process of reciprocated *** would effectively hinder the direct contact between the worn surfaces of AlCrFeNiW_(0.2)Ti_(0.5)coating and YG6 ball,resulting in a decrease of friction coefficient and wear *** the YG6 was an ideal coupled material for AlCrFeNiW_(0.2)Ti_(0.5)coating in seawater,and the coating would become a promising wear-resisting material in ocean environment.

关键词： High-entropy alloy coating Laser cladding Microstructure Microhardness Tribological properties

Fabrication and application of arrays related to two-dimensional materials

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Rare Metals 2022年第1期41卷 262-286页

作者： hui-Li jiang Jia Pan Wei Zhou hui-Min Li Song Liu Institute of Chemical Biology and Nanomedicine(ICBN) State Key Laboratory of Chemo/Biosensing and ChemometricsCollege of Chemistry and Chemical EngineeringHunan UniversityChangsha 410082China

In recent years,two-dimensional(2D)materials have attracted extensive attention from researchers for their unique structures and electrical properties.2D materials have been widely applied in field effect transistors,sensors,and *** is extremely important for practical applications in devices,which requires both minimal crosstalk and high *** fabrication of patterned arrays of 2D materials can realize high-density *** addition,the properties of 2D materials can be also adjusted by the patterned *** this review,we summarize the emerging researches related to 2D materials and ***,the preparation strategies of different arrays have been ***,the applications of arrays have been investigated,such as physical unclonable functions,sensors,energy consumption,photoluminescence enhancement,quantum emitters and ***,the prospects and existing challenges have been proposed.

关键词： 2D materials 2D material arrays Sensors Quantum emitters Photodetectors

Microstructure,Mechanical and Wear Resistance Properties of AlCoCrFeNi_(2.1)-xNi_(3)Al Eutectic High-Entropy Alloy Matrix Composites

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Acta Metallurgica Sinica(English Letters) 2024年第12期37卷 2019-2028页

作者： Li Li Xiao Kong hui jiang Wenna Jiao Di jiang Jichao Ren College of Intelligent Engineering Taishan College of Science and TechnologyTaian271038China College of Mechanical and Electronic Engineering Shandong University of Science and TechnologyQingdao266590China School of Material Science and Engineering Dalian University of TechnologyDalian116081China Qingdao Kompress Energy Technology Co. LtdQingdao266073China

AlCoCrFeNi_(2.1)-xNi_(3)Al(x=0,5.0,7.5,and 10 wt%,denoted as Ni_(3)Al0,Ni_(3)Al5.0,Ni_(3)Al_(7.5),and Ni_(3)Al_(10))eutectic high-entropy alloy(EHEA)matrix composites were fabricated by mechanical alloying and spark plasma sintering *** effects of Ni_(3)Al content on the microstructures,mechanical and wear properties of AlCoCrFeNi_(2.1)EHEA were *** results indicate that the AlCoCrFeNi_(2.1)-xNi_(3)Al composites present cellular grid morphologies composing of FCC/Ll2 and B2 phases,and a small amount of Al_(2)O_(3)and Cr_(7)C_(3)*** addition of Ni_(3)Al significantly enhanced the compressive yield strength,compressive fracture strength,compressive strain and wear properties of the AlCoCrFeNi_(2.1)*** particular,the Ni_(3)Al_(10)composite exhibits excellent comprehensive mechanical *** compressive yield strength,compressive fracture strength and compressive strain of the Ni_(3)Al_(10)composite,are 1845 MPa,2301 MPa and 10.1%,*** friction coefficient,wear width and depth,and mass loss of the Ni_(3)Al_(10)composite were 0.40,0.9 mm,20.5 mm,0.016 g,***,the wear mechanism of the Ni_(3)Al_(10)composite is major abrasive wear with a small amount of adhesive wear.

关键词： Eutectic high-entropy alloy composites Microstructures Mechanical properties Wear properties

Application of a new semi-analytical method to periodic motion due to the J_(22) tesseral harmonic

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Research in Astronomy and Astrophysics 2015年第6期15卷 896-908页

作者： Shou-Cun Hu jiang-hui Ji Yu-hui Zhao Key Laboratory of Planetary Sciences Purple Mountain Observatory Chinese Academy of Sciences

We revisit the issue of constructing the first-order periodic solution that incorporates the J22 tesseral harmonic and developing a new semi-analytical solution that may apply to any orbital eccentricity in [0,1）. In our work, the solution is expressed in a finite compact form composed of several definite integrals with varying integration intervals constrained in [0,Tr], in which the traditional Hansen coefficients are no longer involved. Numerical experiments are also given and compared with the traditional series expansion method, and the results show that the derived solution is capable of dealing with highly eccentric orbits. Therefore, the solution given can provide a new technique to analyze the perturbation characteristics arising from the J22 harmonic.

关键词： celestial mechanics