共查询到19条相似文献,搜索用时 78 毫秒
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根据Jacobson的液体分子自由程理论和液体声速与分子自由程的关系,推导出多元有机混合液声速的温度系数,压力系数和非线性声参量B/A的计算公式,并根据组成多元有机混合液各组分特性参量(密度,自由程,非线性声参量B/A,等压膨胀系数,等温压缩系数等),利用给出的公式对声速的温度系数,压力系数,非线性声参量B/A进行了数值计算,并将计算结果与实验结果进行了比较。 相似文献
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通过液体声速与表面张力系数之间的关系及理想混合液的基本假设 ,导出理想混合液表面张力系数的表达式 ,讨论了二元混合液的表面张力系数 ,给出了计算混合液表面张力系数的新方法 . 相似文献
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弱相互作用二元混合液中的声速计算 总被引:1,自引:0,他引:1
本文在给出超额摩尔绝热压缩系数计算公式的基础上,给出了弱相互作用液体混合物的声速计算公式。对36组弱相互作用二元混合液进行了声速值的计算,结果表明计算值与实验值符合很好,并讨论了二元混合液中声速出现极小值的现象。 相似文献
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Based on Jacobson's molecular free length theory in liquids and the relationship between ultrasonic velocity and the molecular free length in organic liquids, this paper deduces the equations for pressure coefficient and temperature coefficient of ultrasonic velocity and nonlinear acoustic parameter B/A in both of organic liquid and organic liquid binary mixtures. These nonlinear acoustic parameters are evaluated against the measured results and data from other sources. The equations reveal the connections between the nonlinear acoustic parameters and some internal structural of the medium or mixtures e.g. the sizes of molecule, several thermodynamic physical parameters and outside status e.g. condition of pressure and temperature of the liquid or liquid mixture. With the equations the nonlinear acoustic parameter B/A of organic liquid binary mixtures, which is impossible to know without the nonlinear acoustic parameter B/A of the tow components before, can be calculated based on the structural and physical parameters of organic liquid and organic liquid binary mixtures. 相似文献
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Fifteen specimens of tetraalkoxysilanes were prepared and their tentative tetrahedral structures proposed. Ultrasonic velocities were measured over the temperature range of 30–80°C using a multifrequency ultrasonic interferometer. Intermolecular free length, free volume and internal pressure of different classes of compounds were evaluated using the experimentally determined ultrasonic velocity, density, specific heat, thermal expansion, viscosity and molecular weight employing different empirical equations and the data obtained were compared. 相似文献
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Ultrasonic study on organic liquid and binary organic liquid mixtures by using Schaaffs' collision factor theory 总被引:1,自引:0,他引:1 下载免费PDF全文
Based on Schaaff's collision factor theory (CFT) in liquids, the equations for nonlinear ultrasonic parameters in both organic liquid and binary organic liquid mixtures are deduced. The nonlinear ultrasonic parameters, including pressure coefficient, temperature coefficients of ultrasonic velocity, and nonlinear acoustic parameter B/A in both organic liquid and binary organic liquid mixtures, are evaluated for comparison with the measured results and data from other sources. The equations show that the coefficient of ultrasonic velocity and nonlinear acoustic parameter B/A are closely related to molecular interactions. These nonlinear ultrasonic parameters reflect some information of internal structure and outside status of the medium or mixtures. From the exponent of repulsive forces of the molecules, several thermodynamic parameters, pressure and temperature of the medium, the nonlinear ultrasonic parameters and ultrasonic nature of the medium can be evaluated. When evaluating and studying nonlinear acoustic parameter B/A of binary organic liquid mixtures, there is no need to know the nonlinear acoustic parameter B/A of the components. Obviously, the equation reveals the connection between the nonlinear ultrasonic nature and internal structure and outside status of the mixtures more directly and distinctly than traditional mixture law for B/A, e.g. Apfel's and Sehgal's laws for liquid binary mixtures. 相似文献
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Ultrasonic and IR study of intermolecular association through hydrogen bonding in ternary liquid mixtures 总被引:3,自引:0,他引:3
Complex formation in ternary liquid mixtures of dimethylsulfoxide (DMSO) with phenol and o-cresol in carbontetrachloride has been studied by measuring ultrasonic velocity at 2 MHz, in the concentration range of 0.019-0.162 (in mole fraction of DMSO) at varying temperatures of 20, 30 and 40 degrees C. Using measured values of ultrasonic velocity, other parameters such as adiabatic compressibility, intermolecular free length, molar sound velocity, molar compressibility, specific acoustic impedance and molar volume have been evaluated. These parameters have been utilized to study the solute-solute interactions in these systems. The ultrasonic velocity shows a maxima and adiabatic compressibility a corresponding minima as a function of concentration for these mixtures. The results indicate the occurrence of complex formation between unlike molecules through intermolecular hydrogen bonding between oxygen atom of DMSO molecule and hydrogen atom of phenol and o-cresol molecules. The excess values of adiabatic compressibility and intermolecular free length have also been evaluated. The variation of both these parameters with concentration also indicates the possibility of the complex formation in these systems. Further, to investigate the presence of O-HO bond complexes and the strength of molecular association with concentrations, the infrared spectra of both the systems, DMSO-phenol and DMSO-o-cresol, have been recorded for various concentrations at room temperature (20 degrees C). The results obtained using infrared spectroscopy for both the systems also support the occurrence of complex formation through intermolecular hydrogen bonding in these ternary liquid mixtures. 相似文献
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The ultrasonic velocity (C) and density (ρ) have been measured at different frequencies (1MHz, 3MHz and 5 MHz) in the binary
mixtures of acetone with chlorobenzene over the entire range of mole fraction at temperature 303.16K. The data of C and ρ
have been used to evaluate the isentropic compressibility (β), intermolecular free length (Lf) and acoustic impedance (Z) and their excess values to elucidate the molecular association in the mixture. The variation
of these parameters with solute (acetone) indicates the nature of interaction present in the binary mixture. 相似文献
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The ultrasonic velocities of binary liquid mixtures of 1,1,2,2-tetrachloroethane with benzene, toluene,p-xylene, acetone and cyclohexane have been evaluated at 298.15 and 308.15 K using Schaaff’s collision factor theory (CFT),
Jacobson’s free length theory (FLT), Nomoto’s relation and Van Dael ideal mixing relation. The ideal mixing relation gives
the minimum deviation for all the systems except with acetone. The intermolecular free length has also been evaluated using
ultrasonic and thermodynamic methods and the limitations of both the methods have been discussed. The deviations in ultrasonic
velocity and intermolecular free length are discussed in terms of weak interaction between unlike molecules. 相似文献
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LIU Zhenqing 《声学学报:英文版》1995,(4)
I.IntroductionBymeansofu1trasonicwavesthedynamicspecificpropertiesofmolecu1esinmediacouldbeapprehended.Fromthe195ostol96osacousticiansstudiedmo1ecu1aracousticandthermodynamicspecificpropertiesof1iquidsandmixtureswithgreate.th.siasm['-'],andkeptonbringto1ighttheirreportsofrc1evantstudiesinthe1astten-oddyearsl'-'l.overrecentyearstheauthorhasbeenengagedinthemeasurementandstudyofsoundve-locityofsevera1chemica1so1utionsinassociationwithu1trasonicmeasurementstudyofthecon-centrationofsolutionsproduce… 相似文献
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The measurements of ultrasonic velocity and density were made for the ternary mixtures of l-naphthol/2-naphthol with 2-propanone
in benzene at 20, 30 and 40°C in the mole fraction range of 0.00 to 0.05. Adiabatic compressibility and intermolecular free
length have been evaluated using ultrasonic velocity data. The non-linear variation of ultrasonic velocity and allied parameters
with mole fraction indicates solute-solute interactions through hydrogen bonding between unlike molecules. Results of ultrasonic
velocity and density measurements are further supported by FT-IR spectra. The change in transmittance as well as the shift
in the frequency of the representative peak of the OH stretching in FT-IR spectra give inferences about the complex formation. 相似文献
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Density (ρ), ultrasonic velocity (u), adiabatic compressibility (β), apparent molar volume (Ø), acoustic impedance (Z), intermolecular free length (Lf), relative association (RA) of binary mixtures of 2′-chloro-4-methoxy-3-nitro benzil (abbreviated as 2CBe) in ethanol, acetonitrile, chloroform, dioxane and benzene were measured at different concentrations at 298 K. Several useful parameters such as excess density, excess ultrasonic velocity, excess adiabatic compressibility, excess apparent molar volume, excess acoustic impedance and excess intermolecular free length have been calculated. These parameters are used to explain the nature of intermolecular interactions taking place in the binary mixture. The above study is useful in understanding the solute – solvent interactions occurring in different concentrations at room temperature. 相似文献