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Structural Foundation and Geometry of the Material Singularity (and Its Quantum Entanglement)
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作者 Rafael Cañete Mesa 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第3期1095-1137,共43页
In this paper we develop and study, as the second part of one more general development, the energy transmutation equation for the material singularity, previously obtained through the symmetrisation of a wave packet, ... In this paper we develop and study, as the second part of one more general development, the energy transmutation equation for the material singularity, previously obtained through the symmetrisation of a wave packet, that is, we develop the correlation between the terms of this equation, which accounts for the formation of matter from a previous vibrational state, and the different possible energy species. These energetic species are ascribed, in a simplified form, to the equation E¯ω=E¯k+E¯f, which allows us, through its associated phase factor, to gain an insight into the wave character of the kinetic energy and thus to attain the basis of the matter-wave, and all sorts of related phenomenologies, including that concerning quantum entanglement. The formation of the matter was previously identified as an energetic process, analogous to the kinetic one, in which finally the inertial mass is consolidated as a mass in a different phase, now, in addition, the mass of the material singularity is identified as a volumetric density of waves of toroidal geometry created in the process of singularisation or energy transfer between species, which makes it possible to establish the real relation or correspondence between the corpuscular and photonic energy equation (E=mc2=hν), i.e. to explain through m the intimate sense of the first equivalence, which explains what νis in the second one. 展开更多
关键词 Standard Model wave-packet Material Singularity wave-Particle Dualism wave Symmetrisation Matter-wave Energetic Transmutation Quantum Entanglement
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Autler-Townes Splitting in Photoelectron Spectrum of Three-Level Li2 Molecule in Ultrashort Pulse Laser Fields 被引量:3
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作者 胡文辉 元凯军 +2 位作者 韩永昌 束传存 丛书林 《Chinese Physics Letters》 SCIE CAS CSCD 2007年第6期1556-1559,共4页
The Autler-Townes (AT) splitting in femtosecond photoelectron spectrum of three-level Li2 molecules is theoretically investigated using time-dependent quantum wave packet method. With proper femtosecond laser pulses... The Autler-Townes (AT) splitting in femtosecond photoelectron spectrum of three-level Li2 molecules is theoretically investigated using time-dependent quantum wave packet method. With proper femtosecond laser pulses, three peaks of the AT splitting can be observed in the photoelectron spectrum. The AT splitting stems from rapid Rabi oscillation caused by intense ultrashort laser pluses. The effects of laser parameters on the molecular ionization dynamics are also discussed. 展开更多
关键词 wave-packet DYNAMICS MULTIPHOTON IONIZATION POPULATION TRANSFER TRIATOMIC-MOLECULES ELECTRONIC STATES NO MOLECULE STARK SHIFT NA-2 DISSOCIATION SPECTROSCOPY
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自动超声波测厚信号噪声成因及对策分析 被引量:4
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作者 付元杰 《装备制造技术》 2011年第5期88-89,共2页
概述了大型承压特种设备的腐蚀原因和测厚要求,以及自动超声爬行测厚系统的原理,分析了自动爬行超声波测厚信号噪声的成因和测得值失真的原因,并就对策进行了分析。
关键词 自动超声波 测厚 小波包
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非等温喷流中波包的运动学分析
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作者 刘琪麟 赖焕新 《工程热物理学报》 EI CSCD 北大核心 2023年第12期3272-3282,共11页
波包被认为是喷流中一种重要的声辐射源,运动学分析旨在建立波包运动与声辐射的关联模型,但是该模型对于非等温喷流还存在表征波包尺度变化的问题。本文通过对速度、密度与压强场的模态分析来筛选适合于表征非等温喷流中波包的物理量,... 波包被认为是喷流中一种重要的声辐射源,运动学分析旨在建立波包运动与声辐射的关联模型,但是该模型对于非等温喷流还存在表征波包尺度变化的问题。本文通过对速度、密度与压强场的模态分析来筛选适合于表征非等温喷流中波包的物理量,进一步引入了一种表征波包尺度变化的连续函数,在此基础上讨论波包尺度对声辐射的影响。结果表明喷流温度使得压强模态与密度模态的同步特征消失,且改变了压强模态与速度模态之间的耦合关系。压强模态的辐射特征显著,因此运动学分析可以针对压强场来开展。波包包络尺度L和相干衰减尺度Lc使得波包的能量分布呈椭圆形分散到辐射区,从而提高了波包的辐射强度。L仅使得椭圆端部畸变,它对辐射强度的影响比Lc弱。 展开更多
关键词 非等温喷流 波包 相干结构 尺度
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Quantum carpets:efficiently probing fractional revivals in position-dependent mass systems
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作者 Tooba Bibi Sunia Javed Shahid Iqbal 《Communications in Theoretical Physics》 SCIE CAS CSCD 2023年第1期46-54,共9页
Position-dependent-mass systems are of great importance in many physical situations,such as the transport of charge carriers in semiconductors with non-uniform composition and in the theory of many-body interactions i... Position-dependent-mass systems are of great importance in many physical situations,such as the transport of charge carriers in semiconductors with non-uniform composition and in the theory of many-body interactions in condensed matter.Here we investigate,numerically and analytically,the phenomenon of fractional revivals in such systems,which is a generic characteristic manifested by the wave-packet evolution in bounded Hamiltonian systems.Identifying the fractional revivals using specific probes is an important task in the theory of quantum measurement and sensing.We numerically simulate the temporal evolution of probability density and information entropy density,which manifest self-similarly recurring interference patterns,namely,quantum carpets.Our numerical results show that the quantum carpets not only serve as an effective probe for recognizing the fractional revivals of various order but they efficiently describe the effect of spatially-varying mass on the structure of fractional revivals,which is manifested as a symmetry breaking in their designs. 展开更多
关键词 wave-packet dynamics quantum carpets information carpets quantum revivals fractional revivals position-dependent mass schroedinger equation
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Discrete Spectra and Continuous Spectrum of the BarotropicQuasi-Geostrophic Model-A Calculation ofMeteorological Data 被引量:1
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作者 张明华 曾庆存 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1999年第4期487-506,共20页
Atmospheric disturbances at 300 hPa are decomposed into normal modes, referred as discrete—spectrum disturbances which can propagate freely in the observed zonal mean flow, and non—modal transient disturbances, refe... Atmospheric disturbances at 300 hPa are decomposed into normal modes, referred as discrete—spectrum disturbances which can propagate freely in the observed zonal mean flow, and non—modal transient disturbances, referred as continuous—spectrum disturbances which are continuously sheared and eventually absorbed by the zonal flow. It is shown that normal modes represent only a small fraction of the observed atmospheric disturbances, while continuous—spectrum disturbances represent the majority of observed disturbances, even when the basic flow is unstable. Daily variabilities of the observed continuous—spectrum disturbances are presented. They are shown to follow the results of wave—packet theory. Calculations suggest that there are abundant sources to excite continuous—spectrum disturbances in the atmosphere. 展开更多
关键词 Normal mode Discrete-spectrum Continuous-spectrum wave-packet
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耦合谐振子的干涉与波包演化(一) 被引量:2
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《武汉化工学院学报》 2006年第3期87-88,92,共3页
根据谐振子势场中单个粒子的波包函数,推导出了耦合谐振子的波函数和联合几率密度,特别是不可区分粒子的干涉项,并按照可区分粒子与不可区分粒子进行了讨论.
关键词 耦合谐振子 波包 联合几率密度
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Time-dependent treatment of intramolecular energy transfer for HeICl complex
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作者 Zhao, X Bu, YX +1 位作者 Wu, AL Guan, DR 《Chinese Journal of Chemistry》 SCIE CAS CSCD 1997年第3期218-224,共7页
The time-dependent golden wave packet method has been used for calculating the decay widths of vibrational predissociation for HeICl complex in the B state with total angular momentum J=0. This is a good example of in... The time-dependent golden wave packet method has been used for calculating the decay widths of vibrational predissociation for HeICl complex in the B state with total angular momentum J=0. This is a good example of intramolecular energy transfer, We examine the dependence of the final rotational distribution (partial decay width) of ICI fragment an the stretching excitation. It is found that computed final rotational distributions are weakly dependent on the vibrational level being excited. Unlike the smoothly varying rotational distribution for lower initial vibrational levels, for higher initial vibrational levels the rotational distribution indicates the very pronounced oscillatory structure. The analysis of the rotational distribution as a function of propagation time reveals the predominant role of the final states interaction in determining the final rotational distribution. 展开更多
关键词 vibrational predissociation TIME-DEPENDENT wave-packet propagation
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Time-dependent theoretical approach to the influence of laser fields on the resonance enhanced multi-photon ionization of SH radical
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作者 岳大光 郑晓云 +2 位作者 刘浩 王春兴 孟庆田 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第4期1479-1485,共7页
This paper reports that the (2+1) resonance enhanced multi-photon ionization spectra of SH radical in external fields are simulated using the split-operator scheme of time-dependent wave-packet method. Two ionic st... This paper reports that the (2+1) resonance enhanced multi-photon ionization spectra of SH radical in external fields are simulated using the split-operator scheme of time-dependent wave-packet method. Two ionic states, i.e. a1△ and b1∑+, are involved in the simulation. It gives the simulated photoelectron spectra, the population in each electronic state, as well as the projection of the wave-packet in each electronic state on different vibrational states. These results show that the so-called four-state model can represent the experimental results well. 展开更多
关键词 photoelectron spectra time-dependent wave-packet method four-state model multiphoton ionization
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Effect of Pulse Temporal Profile on Autler-Townes Splitting in Photoelectron Spectrum
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作者 元凯军 束传存 丛书林 《Chinese Physics Letters》 SCIE CAS CSCD 2006年第10期2733-2736,共4页
The effect of pulse temporal profiles on the Autler-Townes (AT) splitting in photoelectron spectra is theoretically studied by employing the time-dependent wave packet method for a rotational Na2 molecule. The AT sp... The effect of pulse temporal profiles on the Autler-Townes (AT) splitting in photoelectron spectra is theoretically studied by employing the time-dependent wave packet method for a rotational Na2 molecule. The AT splitting which results from the sufficient Rabi oscillations is affected by the pulse profile and molecular alignment. The AT splitting may be observed only by utilizing proper pulse profiles with a certain intensity. 展开更多
关键词 wave-packet DYNAMICS LASER-PULSES POPULATION TRANSFER TRIATOMIC-MOLECULES IONIZATION PATH STARK SHIFT STATES SPECTROSCOPY ALIGNMENT FIELDS
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用计算机模拟波包通过方势阶 被引量:1
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作者 何菊明 《武汉化工学院学报》 2003年第3期88-90,共3页
用计算机程序建立波包的模型 ,演示粒子在一维方势阶处的行为 .参照本文所示方法 。
关键词 计算机模拟 波包 一维方势阶
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Detection of Electronic Coherence via Two-Dimensional Electronic Spectroscopy in Condensed Phase 被引量:1
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作者 Yu-xiang Weng 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2018年第2期135-151,245,共18页
Two dimensional Fourier transforrn electronic spectroscopy (2DES) in the visible region enables direct observation of complex dynamics of molecules including quantum coherence in the condensed phase. This review aim... Two dimensional Fourier transforrn electronic spectroscopy (2DES) in the visible region enables direct observation of complex dynamics of molecules including quantum coherence in the condensed phase. This review aims to provide a bridge between the principles and intuitive physical description of 2DES for tutorial purpose. Special emphasis is laid upon how 2DES circumvents the restrictions from both uncertainty principle and the wave-packet collapse during the coherent detection, leading to the successful detection of the coherence in terms of energy difference between the eigenstates showing as the quantum beats; then upon the possible mixing among the pure electronic transition, single-rnode and multi-mode coupled vibronic transition leading to the observed beating phenomena. Finally, recent ad- vances in experimentally distinguishing between the electronic coherence and the vibrational coherence are briefly discussed. 展开更多
关键词 Quantum coherence Uncertainty principle wave-packet collapse Multi-rnodevibronic coupling Two dimensional electronic spectroscopy
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Differential Cross Sections for the H+D2O→HD+OD Reaction: a Full Dimensional State-to-State Quantum Dynamics Study
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作者 Zhi-qiang Zhao Shu Liu Dong H. Zhang 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2017年第1期16-24,I0001,共10页
The time-dependent wave-packet method was employed to calculate the first full-dimensional state-to-state differential cross sections (DCS) for the title reaction with D2O in the ground and the first symmetric (100... The time-dependent wave-packet method was employed to calculate the first full-dimensional state-to-state differential cross sections (DCS) for the title reaction with D2O in the ground and the first symmetric (100) and asymmetric stretching (001) excited states. The calculated DCSs for these three initial states are strongly backward peaked at low collision energies. With the increase of collision energy, these DCSs become increasingly broader with the peak position shifting gradually to a smaller angle, consistent with the fact that the title reaction is a direct reaction via an abstraction mechanism. It is found that the (100) and (001) states not only have roughly the same integral cross sections, but also have essentially identical DCS, which are very close to that for the ground state at the same total energy of reaction. The reaction produces a small fraction of OD in the v=1 state, with the population close to the relative reactivity between the ground and vibrationally excited states, therefore confirming the experimental result of Zare et al. and the local mode picture [J. Phys. Chem. 97, 2204 (1993)]. Unexpectedly, the stretching excitation reduces the rotation excitation of product HD at the same total energy. 展开更多
关键词 State-to-state Differential cross section Time-dependent wave-packet method
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measurement weak repeatability covariant condition wave-packet collapse
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作者 吴照奇 朱传喜 王建辉 《Communications in Theoretical Physics》 SCIE CAS CSCD 2016年第2期165-168,共4页
The conflict between the dynamics postulate(unitary evolution) and the measurement postulate(wavepacket collapse) of quantum mechanics has been reconciled by Zurek from an information transfer perspective [Phys.Re... The conflict between the dynamics postulate(unitary evolution) and the measurement postulate(wavepacket collapse) of quantum mechanics has been reconciled by Zurek from an information transfer perspective [Phys.Rev. A 76(2007) 052110], and has further been extended to a more general scenario [Phys. Rev. A 87(2013) 052111].In this paper, we reconsider Zurek's new derivation by using weak repeatability postulate or covariant condition instead of repeatability postulate. 展开更多
关键词 wave-packet Collapse Based on Weak Repeatability or Covariant Condition
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量子力学的Goos-Hanchen效应
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作者 张剑 《大学物理》 北大核心 2004年第7期57-59,共3页
指出量子力学也存在类似于电磁波的Goos-Hanchen效应.用二维波包在二维势阶的散射模型分析了Goos-Hanchen效应的内在原因.
关键词 Goos-Hanchen效应 波包 全反射
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Zitterbewegung of Dirac quasiparticles emerged in a Su-Schrieffer-Heeger lattice
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作者 Yue Hu Zheng-Xin Guo +1 位作者 Ze-Ming Zhong Zhi Li 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第11期182-188,共7页
We analytically and numerically investigate the dynamical properties of the tilted dispersion relativistic quasiparticles emerged in a cold atomic optical lattice system.By introducing the next nearest neighboring(NNN... We analytically and numerically investigate the dynamical properties of the tilted dispersion relativistic quasiparticles emerged in a cold atomic optical lattice system.By introducing the next nearest neighboring(NNN)hopping term into Su-Schrieffer-Heeger(SSH)model,the Dirac quasiparticles with tilted dispersion relation are realized.The results show that the tilted dispersion causes a drift in relativistic quasiparticles rather than affecting interference behavior between inner states.To be specific,the relativistic phenomena of the quasiparticles induced by the inner state interference(such as Zitterbewegung,Klein paradox,etc.)is completely unaffected by the tilted dispersion.In order to distinguish the drift induced by tilted dispersion and common initial velocity,we calculate the momentum distribution of the relativistic quasiparticles.We obtain the difference between the drift induced by initial velocity and tilted dispersion.The former affects the ZB,while the latter does not.By using this character,we propose a quench dynamics scheme to obtain a stable mono-spin state.The proposed cold atomic lattice system would provide a promising platform in exploring the intrinsic exotic physics of relativistic quasiparticles and the related systems. 展开更多
关键词 tilted dispersion wave-packet dynamics quantum quench
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Laser-induced Alignment and Coulomb Explosion of CO2
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作者 Cheng-yin Wu Hong-yan Jiang +1 位作者 Zhi-feng Wu Qi-huang Gong 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2009年第6期571-576,J0001,共7页
Dynamic processes of CO2 are experimentally studied in intense femtosecond laser fields with laser intensity varying from 1×10^13 W/cm^2 to 6×10^14 W/cm^2. When the laser intensity is below the ionization th... Dynamic processes of CO2 are experimentally studied in intense femtosecond laser fields with laser intensity varying from 1×10^13 W/cm^2 to 6×10^14 W/cm^2. When the laser intensity is below the ionization threshold, a coherent rotational wave-packet is formed for CO2 at room temperature through nonadiabatic rotational excitation. The evolution of the wave-packet leads to transient alignment. The field-free alignment revives periodically after the laser pulse is over. The revival structure can be modified by a second laser pulse for the rotational wave-packet through precisely adjusting the time delays between the two laser pulses. When the laser intensity excesses the ionization threshold, ionization and Coulomb explosion occur. The atomic ions C^m+ (re=1-3) and On+ (n=1-3) observed in the experiment exhibit highly anisotropic angular distributions relative to the laser polarization. Using two linearly polarized laser pulses with crossed polarization, we conclude that the anisotropic angular distribution results from dynamic alignment, in which the rising edge of the laser pulse aligns the neutral CO2 along the laser polarization direction prior to ionization. 展开更多
关键词 Rotational wave-packet Field-free alignment Coulomb explosion
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State-to-state dynamics of reactions H+DH'(v=0,j=0)→HH'(v',j')+D/HD(v',j')+H'with time-dependent quantum wave packet method
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作者 Juan Zhao Da-Guang Yue +3 位作者 Lu-Lu Zhang Shang Gao Zhong-Bo Liu Qing-Tian Meng 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第7期192-199,共8页
State-to-state time-dependent quantum dynamics calculations have been carried out to study H+DH'→HH'+D/HD+H'reactions on BKMP2 surface.The total integral cross sections of both reactions are in good agree... State-to-state time-dependent quantum dynamics calculations have been carried out to study H+DH'→HH'+D/HD+H'reactions on BKMP2 surface.The total integral cross sections of both reactions are in good agreement with earlier theoretical and experimental results,moreover the rotational state-resolved reaction cross sections of H+DH'→HH‘+D at collision energy Ec=0.5 eV are closer to the experimental values than the ones calculated by Chao et al[J.Chem.Phys.1178341(2002)],which proves the higher precision of the quantum calculation in this work.In addition,the state-to-state dynamics of H+DH'→HD'+H reaction channel have been discussed in detail,and the differences of the micro-mechanism of the two reaction channels have been revealed and analyzed clearly. 展开更多
关键词 state-to-state time-dependent quantum wave-packet method differential cross sections
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2008年低温雨雪天气扰动能量的积累和传播 被引量:20
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作者 葛非 肖天贵 +2 位作者 金荣花 陈伟斌 唐玮玮 《气象》 CSCD 北大核心 2008年第12期11-20,共10页
利用NCEP/NCAR再分析资料,通过波包传播的诊断方法,对2008年1月我国南方地区大范围低温雨雪天气期间波包传播和积累进行了分析与研究。分析表明,中低层500hPa和700hPa高度场的波包传播特征能够较好地反映期间出现的4次低温雨雪天气过程... 利用NCEP/NCAR再分析资料,通过波包传播的诊断方法,对2008年1月我国南方地区大范围低温雨雪天气期间波包传播和积累进行了分析与研究。分析表明,中低层500hPa和700hPa高度场的波包传播特征能够较好地反映期间出现的4次低温雨雪天气过程。4次雨雪过程基本上产生于波包扰动能量积累的高值时段或处于低压系统持续稳定阶段,雨雪天气处于波包大值区控制下。波包值的经向和纬向传播特征表明2008年1月我国南方地区持续低温雨雪天气过程,主要受到青藏高原南缘系统异常活跃的影响,南支槽活动频繁有利于来自印度洋和孟加拉湾的暖湿气流沿云贵高原不断向我国输送,继而为我国长江中下游以及其南部地区低温雨雪天气提供了充足的水汽来源。偏北路径的冷空气,副高西南侧偏东气流的扰动能量的传播和积累,在波包传播图上都有一定的反映。该研究对进一步利用波包传播图预报天气过程提供了有意义的一种思路。 展开更多
关键词 波包传播诊断 低温雨雪天气 扰动能量
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混凝土超声检测技术的研究与实现 被引量:11
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作者 邵志学 石立华 张琦 《振动.测试与诊断》 EI CSCD 北大核心 2012年第3期397-401,513,共5页
针对混凝土结构无损检测的需要,提出了一种超声激励脉冲产生的方法。由于超声波信号在混凝土中衰减快,为了提高检测系统的探测能力,增强回波信号,提高超声激励脉冲幅值,采用一种高频继电器实现了电磁脉冲源,并通过水和混凝土两种不同介... 针对混凝土结构无损检测的需要,提出了一种超声激励脉冲产生的方法。由于超声波信号在混凝土中衰减快,为了提高检测系统的探测能力,增强回波信号,提高超声激励脉冲幅值,采用一种高频继电器实现了电磁脉冲源,并通过水和混凝土两种不同介质的无损检测试验验证其可用性。为了实现混凝土结构的高效精细检测,采用波包分解技术对检测数据处理分析,通过合成孔径技术成像,研制了系统样机。不同混凝土结构试块的检测成像试验表明,系统探测深度可达1m,可以较准确成像显示混凝土结构内部嵌入物的位置。 展开更多
关键词 超声检测 电磁脉冲源 波包分解 合成孔径技术
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