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Synthesis and Electrical Properties of Li-modified Bi_(0.5)Na_(0.5)TiO_3-BaTiO_3 Lead-free Piezoelectric Ceramics

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Journal of Materials Science & Technology 2009年第6期25卷 777-780页

作者： Yunweu liao Dingquan Xiao Institute of Applied Chemistry China West Normal University Nanchong 637002 China Department of Materials Science Sichuan University Chengdu 610064 China

Lead-free piezoelectric ceramics （1-y）Bi0.5（Na1-xLix）0.5TiO3-yBaTiO3 with x=0-0.125 and y=0.02-0.12 were fabricated by a solid-state reaction process, and their dielectric, piezoelectric and ferroelectric properties were investigated. The results show that the addition of Li^＋ significantly improves the sintering performance and piezoelectric properties of the ceramics. X-ray diffraction （XRD） patterns indicate that the ceramics possess pure perovskite structure. At room temperature, the ceramics provide high piezoelectric charge constant d33 （up to 210 pC/N）, high planar electromechanical coupling factor kp （34.5%）, large remanent polarization Pr （up to 40 μC/cm^2）, and low coercive field Ec （3.0 kV/mm）, which indicates that （1-y）Bi0.5（Na1-xLix）0.5TiO3-yBaTi03 is a good lead-free piezoelectric ceramic.

关键词： Lead-free piezoelectric ceramic Bi0.5Na0.5TiO3 Microstructure Piezoelectricity

Boundedness of Singular Integral Operators on Herz-Morrey Spaces with Variable Exponent

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Chinese Annals of Mathematics,Series B 2020年第1期41卷 99-116页

作者： Hongbin WANG Fanghui liao School of Mathematics and Statistics Shandong University of TechnologyZibo 255049ShandongChina School of Mathematics and Computational Science Xiangtan UniversityXiangtan 411105HunanChina

Let Ω ∈ Ls(S^n-1)(s>1) be a homogeneous function of degree zero and b be a BMO function or Lipschitz function. In this paper, the authors obtain some boundedness of the Calderón-Zygmund singular integral operator T... 详细信息

关键词： Calderón-Zygmund singular integral Commutator Herz-Morrey space Variable exponent

A new construction for involutions over finite fields

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Frontiers of Mathematics in China 2022年第4期17卷 553-565页

作者： Zhaohui ZHANG Qunying liao College of Mathematical Science Sichuan Normal UniversityChengdu610066China

In 2020,Niu et al.[***.,2020,12(2):165–185]studied the fixed points of involutions over the finite field with *** paper further discusses the relationship between the fixed points set and the non-fixed points set of two involutions f_(1)(x)and f_(2)(x)over the finite field F_(q),and then obtains a necessary and sufficient condition for that the composite function f_(1)■f_(2)(x)is also an involution over F_(q).In particular,a special class of involutions over some finite fields is determined completely.

关键词： Permutation polynomial involution fixed point non-fixed point

Traversable Lorentzian Wormholes in Brans-Dicke’s and Induced Gravity Theories

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Chinese Physics Letters 1996年第12期13卷 881-884页

作者： ZHAO Feng LIU liao Department of Biomedical Engineering Capital University of Medical SciencesBeijing 100054 Department of Physics Beijing Normal UniversityBeijing 100875

We generalize Visser’s method to construct traversable Lorentzian wormholes from surgically modified Friedman-Robertson-Walker spacetimes in both Brans-Dicke’s theory and induced theory of *** result shows,in both c... 详细信息

关键词： Brans Dicke theory

Pathophysiology and Individualized Management of Vasovagal Syncope and Postural Tachycardia Syndrome in Children and Adolescents:An Update

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Neuroscience Bulletin 2020年第6期36卷 667-681页

作者： Ying liao Junbao Du Department of Pediatrics Peking University First HospitalBeijing 100034China

Vasovagal syncope(VVS) and postural tachycardia syndrome(POTS) are the main forms of orthostatic intolerance in pediatrics and both are underlying causes of neurally-mediated *** recent years,increasing attention has been paid to the management of VVS and POTS in children and adolescents.A number of potential mechanisms are involved in their pathophysiology,but the leading cause of symptoms varies among patients.A few studies thus have focused on the individualized treatment of VVS or POTS based on selected hemodynamic parameters or biomarkers that can predict the therapeutic effect of certain therapies and improve their *** review summarizes the latest developments in individualized treatment of VVS and POTS in children and indicates directions for further research in this field.

关键词： Vasovagal syncope Postural tachycardia syndrome Individualized management Pathophysiology Children Adolescents

Exploring the influence of various factors on microwave radiation image simulation for Moon-based Earth observation

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Frontiers of Earth Science 2020年第2期14卷 430-445页

作者： Linan YUAN Jingjuan liao Key Laboratory of Digital Earth Science Aerospace Information Research InstituteChinese Academy of SciencesBeijing 100094China University of Chinese Academy of Sciences Beijing 100049China

Earth observation technologies are important for obtaining geospatial information on the Earth’s surface and are used widely in many disciplines,such as resource surveying,environmental monitoring,and evolutionary ***,it is a challenge for existing Earth observation platforms to acquire this type of data rapidly on a global scale due to limitations in orbital altitude and field of view;thus development of an advanced platform for Earth observation is *** a natural satellite of the Earth,placement of various sensors on the Moon could possibly facilitate comprehensive,continuous,and longterm observations of the *** is a relatively new concept and the study is still at the preliminary stage with no actual Moon-based Earth observation data available at this *** understand the characteristics of Moon-based microwave radiation,several physical factors that potentially influence microwave radiation imaging,e.g.,time zone correction,relative movement of the Earth-Moon,atmospheric radiative transfer,and the effect of the ionosphere,were *** on comprehensive analysis of these factors,the Moon-based microwave brightness temperature images were simulated using spaceborne temperature *** results show that time zone correction ensures that the simulation images may be obtained at Coordinated Universal Time(UTC)and that the relative movement of the Earth-Moon affects the positions of the nadir and Moon-based *** effect of the atmosphere on Moon-based observation is dependent on various parameters,such as atmospheric pressure,temperature,humidity,water vapor,carbon dioxide,oxygen,the viewing zenith angle and microwave *** factors have an effect on atmospheric transmittance and propagation of upward and downward *** microwaves propagate through the ionosphere,the attenuation is related to frequency and viewing zenith *** on initial studies,the simulation results suggest Moon-based microwave radiat

关键词： Moon-based Earth observation microwave brightness temperature simulation relative movement of Earth-Moon atmospheric radiative transfer ionosphere

Joint Multi-Domain Channel Estimation Based on Sparse Bayesian Learning for OTFS System

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China Communications 2023年第1期20卷 14-23页

作者： Yong liao Xue Li School of Microelectronics and Communication Engineering Chongqing UniversityChongqing 400044China

Since orthogonal time-frequency space(OTFS)can effectively handle the problems caused by Doppler effect in high-mobility environment,it has gradually become a promising candidate for modulation scheme in the next generation of mobile ***,the inter-Doppler interference(IDI)problem caused by fractional Doppler poses great challenges to channel *** avoid this problem,this paper proposes a joint time and delayDoppler(DD)domain based on sparse Bayesian learning(SBL)channel estimation ***,we derive the original channel response(OCR)from the time domain channel impulse response(CIR),which can reflect the channel variation during one OTFS *** with the traditional channel model,the OCR can avoid the IDI *** that,the dimension of OCR is reduced by using the basis expansion model(BEM)and the relationship between the time and DD domain channel model,so that we have turned the underdetermined problem into an overdetermined ***,in terms of sparsity of channel in delay domain,SBL algorithm is used to estimate the basis coefficients in the BEM without any priori information of *** simulation results show the effectiveness and superiority of the proposed channel estimation algorithm.

关键词： OTFS sparse Bayesian learning basis expansion model channel estimation

Effects of combination of plant and microorganism on degradation of simazine in soil

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Journal of Environmental Sciences 2008年第2期20卷 195-198页

作者： liao Min XIE Xiaomei College of Environmental and Resources Sciences Zhejiang University Hangzhou 310029 China

The degradative characteristics of simazine （SIM）, microbial biomass carbon, plate counts of heterotrophic bacteria and most probably number （MPN） of SIM degraders in uninoculated non-rhizosphere soil, uninoculated rhizosphere soil, inoculated non- rhizosphere soil, and inoculated rhizosphere soil were measured. At the initial concentration of 20 mg SIM/kg soil, the half-lives of SIM in the four treated soils were measured to be 73.0, 52.9, 16.9, and 7.8 d, respectively, and corresponding kinetic data fitted first-order kinetics. The experimental results indicated that higher degradation rates of SIM were observed in rhizosphere soils, especially in inoculated rhizosphere soil. The degradative characteristics of SIM were closely related to microbial process. Vegetation could enhance the magnitude of rhizosphere microbial communities, microbial biomass content, and heterotrophic bacterial community, but did little to influence those community components responsible for SIM degradation. This suggested that rhizosphere soil inoculated with microorganisms-degrading target herbicides was a useful pathway to achieve rapid degradation of the herbicides in soil.

关键词： bioremediation degradation rhizosphere simazine (SIM)

In-situ formation of perylene in lacustrine sediments and its geochemical significance

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Acta Geochimica 2020年第4期39卷 587-594页

作者： Jianyang Guo Haiqing liao State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550002China State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China

To identify the possible sources and formation mechanism of perylene in sediments,temporal trends of perylene and other polycyclic aromatic hydrocarbons,as well as the organic matters,were analyzed in sediment cores from Dianchi Lake and Sihailongwan Maar Lake in *** high concentrations of perylene were observed in both cores and increased gradually with the sediment *** identification suggested that perylene in both cores were of primarily diagenetic origin,other than the anthropogenic *** terrigenous and aquatic organic matters could be the source of perylene in sediments and diagenetic formation of perylene in sediment is kinetically controlled by the microbial activities under anaerobic *** evidence points to the fact that the formation of perylene in sediment should be an index of the microbial activities and environmental conditions,other than the source of specific organic matters or *** addition,we should be cautious when using any geochemical indicators involving the microbial alternation.

关键词： Sediment core Source identification Formation mechanism Organic matters