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sound velocity and related properties of seafloor sediments in the Bering Sea and Chukchi Sea

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Acta Oceanologica Sinica 2015年第5期34卷 75-80页

作者： MENG Xiangmei LI Guanbao HAN Guozhong KAN Guangming First Institute of Oceanography State Oceanic Administration Key Laboratory of Marine Sedimentology and Environmental Geology State Oceanic Administration

The Bering Sea shelf and Chukchi Sea shelf are believed to hold enormous oil and gas reserves which have attracted a lot of geophysical surveys. For the interpretation of acoustic geophysical survey results, sediment sound velocity is one of the main parameters. On seven sediment cores collected from the Bering Sea and Chukchi Sea during the 5th Chinese National Arctic Research Expedition, sound velocity measurements were made at 35, 50, 100, 135, 150, 174, 200, and 250 kHz using eight separate pairs of ultrasonic transducers. The measured sound velocities range from 1 425.1 m/s to 1 606.4 m/s and are dispersive with the degrees of dispersion from 2.2% to 4.0% over a frequency range of 35-250 kHz. After the sound velocity measurements, the measurements of selected geotechnical properties and the Scanning Electron Microscopic observation of microstructure were also made on the sediment cores. The results show that the seafioor sediments are composed of silty sand, sandy silt, coarse silt, clayey silt, sand-silt-clay and silty clay. Aggregate and diatom debris is found in the seafloor sediments. Through comparative analysis of microphotographs and geotechnical properties, it is assumed that the large pore spaces between aggregates and the intraparticulate porosity of diatom debris increase the porosity of the seafioor sediments, and affect other geotechnical properties. The correlation analysis of sound velocity and geotechnical properties shows that the correlation of sound velocity with porosity and wet bulk density is extreme significant, while the correlation of sound velocity with clay content, mean grain size and organic content is not significant. The regression equations between porosity, wet bulk density and sound velocity based on best-fit polynomial are given.

关键词： Bering Sea Chukchi Sea sound velocity geotechnical properties microstructure

Pressure calibration and sound velocity measurement to 12 GPa in multi-anvil apparatus

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Acta Geochimica 2021年第4期40卷 525-531页

作者： Wei Song Shuangming Shan Qizhe Tang Chang Su Yonggang Liu Key Laboratory of High-Temperature and High-Pressure Study of the Earth’s Interior Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China School of Information Engineering Huzhou UniversityHuzhou 313000China Institute of Disaster Prevention Sanhe 065201China

We performed the pressure calibration to 12 GPa for 14/6 type(octahedron edge length/WC truncated edge length,in mm) cell assembly in DS 6 × 1400 multi-anvil apparatus by using the phase transitions in Bi(Ⅰ-Ⅱ2.55 GPa,Ⅲ-Ⅴ 7.67 GPa) and ZnTe(LPP-HPP Ⅰ 9.6 GPa,HPP Ⅰ-Ⅱ 12.0 GPa).As verification and application,sound velocity measurements on poly crystalline Al_(2)O_(3) to 12 GPa at room temperature were conducted and the ultrasonic result is in good agreement with previous reports.It demonstrates the feasibility of performing sound velocity measurements close to the mantle transition zone pressure condition in our laboratory.

关键词： Pressure calibration sound velocity Multi-anvil apparatus Polycrystalline alumina

The universal sound velocity formula for the strongly interacting unitary Fermi gas

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Chinese Physics B 2011年第2期20卷 93-97页

作者：刘可陈继胜 Department of Physics Central China Normal University

Due to the scale invariance, the thermodynamic laws of strongly interacting limit unitary Fermi gas can be similar to those of non-interacting ideal gas. For example, the virial theorem between pressure and energy density of the ideal gas P = 2E/aV is still satisfied by the unitary Fermi gas. This paper analyses the sound velocity of unitary Fermi gases with the quasi-linear approximation. For comparison, the sound velocities for the ideal Boltzmann, Bose and Fermi gas are also given. Quite interestingly, the sound velocity formula for the ideal non-interacting gas is found to be satisfied by the unitary Fermi gas in different temperature regions.

关键词： unitary Fermi gas sound velocity universal thermodynamics

Relationships of the internodal distance of biological tissue with its sound velocity and attenuation at high frequency in doublet mechanics

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Chinese Physics B 2015年第4期24卷 257-261页

作者：程凯旋吴融融刘晓宙刘杰惠龚秀芬吴君汝 Key Laboratory of Modern Acoustics Institute of Acoustics Nanjing University State Key Laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences Department of Physics University of Vermont

In view of the discrete characteristics of biological tissue, doublet mechanics has demonstrated its advantages in the mathematic description of tissue in terms of high frequency （〉 10 MHz） ultrasound. In this paper, we take human breast biopsies as an example to study the influence of the internodal distance, a microscope parameter in biological tissue in doublet mechanics, on the sound velocity and attenuation by numerical simulation. The internodal distance causes the sound velocity and attenuation in biological tissue to change with the increase of frequency. The magnitude of such a change in pathological tissue is distinctly different from that in normal tissue, which can be used to differentiate pathological tissue from normal tissue and can depict the diseased tissue structure by obtaining the sound and attenuation distribution in the sample at high ultrasound frequency. A comparison of sensitivity between the doublet model and conventional continuum model is made, indicating that this is a new method of characterizing ultrasound tissue and diagnosing diseases.

关键词： doublet mechanics sound velocity sound attenuation ultrasound tissue characteristics

The sound velocity and bulk properties of sediments in the Bohai Sea and the Yellow Sea of China

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Acta Oceanologica Sinica 2016年第7期35卷 76-86页

作者： ZHENG Jiewen LIU Baohua KAN guangming LI Guanbao PEI Yanliang LIU Xiaolei Key Laboratory of Marine Sedimentology and Environmental Geology of State Oceanic Administration State Oceanic Administration Qingdao 266061 China First Institute of Oceanography State Oceanic Administration Qingdao 266061 China Qingdao National Laboratory for Marine Science and Technology Qingdao 266237 China National Deep Sea Center State Oceanic Administration Qingdao 266237 China Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering Ocean University of China Qingdao 266100 China

In order to investigate the correlation between a sound velocity and sediment bulk properties and explore the influence of frequency dependence of the sound velocity on the prediction of the sediment properties by the sound velocity, a compressional wave velocity is measured at frequencies of 25-250 kHz on marine sediment samples collected from the Bohai Sea and the Yellow Sea in laboratory, together with the geotechnical parameters of sediments. The results indicate that the sound velocity ranges from 1.232 to 1.721 km/s for the collected sediment samples with a significant dispersion within the series measuring frequency. Poorly sorted sediments are highly dispersive nearly with a positive linear relationship. The porosity shows a better negative logarithmic correlation with the sound velocity compared with other geotechnical parameters. Generally, the sound velocity increases with the increasing of the average particle size, sand content, wet and dry bulk densities, and decreasing of the clay content, and water content. An important point should be demonstrated that the higher correlation can be obtained when the measuring frequency is low within the frequency ranges from 25 to 250 kHz since the inhomogeneity of sediment properties has a more remarkably influence on the laboratory sound velocity measurement at the high frequency.

关键词： sound velocity particle composition physical properties frequency dispersion empirical equation

Influences of Medium Structure of Three-Phase Seabed Deposit on sound velocity

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China Ocean Engineering 2001年第4期16卷 579-588页

作者：徐长节蔡袁强 Department of Civil Engineering Zhejiung University Hangzhou 310027 China

Based on the former research, the mechanism of the influence of the medium structure on the sound velocity of the three-phase seabed deposit is discussed by theoretical method. Through analysis of several structure models of three-phase seabed deposit, an equation of sound velocity is presented, which can describe the effect of structure of three-phase deposit on its acoustic velocity. Seen form the derived equation, the equations of the sound velocity of the deposits with different medium structures are different, the influence of the medium structure on the sound velocity is apparent. The equation in the paper provides the theoretical basis to understand the mechanics properties through sound velocity test, and it can be easily adopted in engineering. The influences of the parameters of deposits, void ratio, gas concentration and modulus on sound velocity through the deposit are investigated by numerical analysis of the acoustic velocity. Numerical result shows that the sound velocity of three-phase medium is affected by void ratio, gas concentration and body modulus, and the sound velocity generally increases with the gas concentration increasing. The results of the paper can be helpful to the acoustic method.

关键词： three-phase seabed deposit medium structure sound velocity

Bulk sound velocity of porous materials at high pressures

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Chinese Physics B 2002年第11期11卷 1188-1192页

作者：耿华运吴强等 LaboratoryforShockWaveandDeonationphysicsResearch SouthwestInstituteofFluidPhysicsPOBox919-012Mianyang621900CHina LaboratoryforShockWaveandDeonationphysicsResearch SouthwestInstituteofFluidPhysics

A correction of Walsh's method for bulk sound velocity calculation for shocked porous materials is accomplishedbased on the Wu-Jing thermodynamic equation of state. The corrected bulk velocities for solid and porous sampleswith low porosities are in good agreement with the corresponding experimental data published previously. On the basisof this corrected equation, the influence of thermoelectrons on the bulk velocity of shocked materials is discussed indetail at pressures of 50, 70 and 200 GPa. Some interesting phenomena are revealed, which seem to be the uniquefeatures of a dynamic-pressure-loading process and could not be found in static experiments.

关键词： porous materials high pressure sound velocity shock wave

Elastic properties of disordered binary hcp-Fe alloys under high pressure: Effects of light elements

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ChemPhysMater 2023年第2期2卷 155-163页

作者： Zhenwei Niu Shuqiong Zeng Mei Tang Zaixiu Yang Laboratory for Extreme Conditions Matter Properties Southwest University of Science and TechnologyMianyang 621010China Fundamental Science on Nuclear Wastes and Environmental Safety Laboratory Southwest University of Science and TechnologyMianyang 621010China Key Laboratory of Science and Technology on Wear and Protection of Materials Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China

The effects of light elements on the elastic properties of disordered binary hcp-Fe alloys were investigated at high pressures using plane-wave density functional theory combined with the Monte Carlo special quasi-random structure method.We found that the increase in the O content in hcp-Fe had a more pronounced effect on the sound velocity than Si,S,and C.The longitudinal wave velocity was decreased by∼6%with 2%O content,which was a much greater decrease than the values of 0.6%and 2%induced by the same content of Si and S,respectively,under high pressures.Compared with the other three light elements,the longitudinal wave velocity of the Fe-C alloy exhibited the most gradual decreasing with increasing C content.In addition,the effects of different O and S contents on the anisotropy of hcp-Fe alloys strongly depended on the variation in pressure,whereas the pressure only slightly affected the anisotropy of Fe-Si alloy systems.

关键词： hcp-Fe alloys Elastic property sound velocity Light elements

Ultrasonic, Volumetric and Isentropic Compressibility of Binary Mixtures of 1,4-Dioxane with Primary Alcohols at 303.15 K

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Open Journal of Physical Chemistry 2021年第3期11卷 168-181页

作者： Seema Agarwal Dhirendra Kumar Sharma Department of chemistry Bundelkhand University Jhansi Jhansi Utter Pradesh India

Density, viscosity and sound velocity of six binary liquid mixtures of methanol, ethanol, propanol, butanol, hexanol and octanol with 1,4-dioxane have been measured over the entire range of composition at temperature 303.15K. From the experimental densities, viscosities and sound velocity, the excess molar volume (VE), deviation in viscosity (Δη) and deviation in isentropic compressibility (ΔKS) have been calculated. The results have been used to discuss the nature and strength of intermolecular interactions in these mixtures.

关键词： Density Viscosity sound velocity Excess Molar Volume Viscosity Deviation Isentropic Compressibility Binary Mixtures Alcohols