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Thermophysical properties have wide applications in various fields like chemical industries, mass and heat transfer processes, design and engineering calculations of industrial plants and their evaluation in liquid mixtures gives us a better understanding of intermolecular interactions taking place therein. The binary liquid mixtures under the current study comprise a range of alkanones viz. 2-Propanone, 2-Butanone, 2-Pentanone and 2-Heptanone with aromatic amines like Aniline, N-methylaniline and Pyridine at temperatures 293.15 K to 303.15 K which have multifarious industrial applications. In the present investigation, ultrasonic velocity (u) studies have been carried out using five approaches at three temperatures. Furthermore, surface tension (σ) , acoustical impedance (z) and thermoacoustical parameters along with non-linearity parameters (B/A) have been evaluated. The variations in molecular interactions are well understood through interaction parameters (χ) . The obtained results indicate that the order of interactions is Pyridine < N-methylaniline < Aniline for a specific alkanone and 2-Propanone > 2-Butanone > 2-Pentanone > 2-Heptanone for a given amine at all three temperatures. The study of thermophysical properties have been elaborated to understand the order of the interactions between various amines and alkanones. [ABSTRACT FROM AUTHOR]

This work highlights a scale-up study for microwave-assisted synthesis of solketal using ultrasonic velocity to monitor the progress of the reaction in combination with other analytical methods like GC–MS. The work aims to quantify the acetalization of glycerol to solketal using modified sulfated zirconia (Zr-S-400, Zr600-S-600, Zr600-S-400) as a catalyst. Stirring speed, catalyst dosing, and reactant ratio were optimized using response surface methodology to achieve maximum conversion. The catalyst (Zr-S-400) was doped with a 0.5 M solution of manganese acetate and nickel sulfate by the wet impregnation method, and catalytic activity was compared with the un-doped Zr-S-400. A maximum conversion of 89% was observed with an undoped Zr-S-400 catalyst. After metal doping, acidity as well as surface area decrease due to the aggregation of metals on the catalyst surface and also inside the pores of the catalyst. The conversion was further improved to 93% by increasing the acidity of the catalyst. A CSTR reactor model has been developed using the kinetic data to scale up the reaction. [ABSTRACT FROM AUTHOR]

This study investigates the use of a non-destructive ultrasonic pulse-echo method to characterize argan oil and other vegetable oils with similar fatty acid profiles. Ultrasonic parameters such as velocity, acoustic attenuation and reflection coefficient were measured across different temperatures. These parameters were used to create predictive models of ultrasonic velocity using partial least squares regression. Results demonstrated significant correlations between ultrasonic properties, oil temperature and fatty acid content. Specifically, ultrasonic velocity was found to be directly proportional to the content of saturated fatty acids and inversely proportional to the content of monounsaturated and polyunsaturated fatty acids. The reflection coefficient was also found to correlate with the fatty acid composition and temperature of the oils. Additionally, both ultrasonic velocity and acoustic attenuation decreased as the temperature increased from 25 °C to 50 °C. At 25 °C, the acoustic attenuation for argan oil was 22.37 Np/m, decreasing to 11.37 Np/m at 50 °C. These correlations allowed for the differentiation between food-grade argan oil, argan oil from seeds regurgitated by goats, sesame oil and peanut oil. The developed predictive models exhibited high coefficients of determination, with a value of 97.03 for argan oil, indicating strong agreement between measured and predicted ultrasonic velocities. This research highlights the potential of ultrasonic techniques for oil characterization and quality control. [ABSTRACT FROM AUTHOR]

Forecasting various forms of intermolecular contact and the degree to which the solute and solvent are bonded is highly advantageous when using thermo‐acoustical and volumetric data. Both salts and vitamins are abundant in the human body. A variety of thermo‐acoustical and volumetric properties (viz. velocity [U], density [ρ], adiabatic compressibility [β], surface tension [σ], specific heat ratio [γ], acoustic impedance [Z], relative association [RA], relaxation strength [r], isothermal compressibility [kT], and nonlinearity parameter [B/A]) are investigated in this study. Of the vitamin B3 + H2O and vitamin B3 + H2O + MgCl2 systems have been examined. Through solvation and hydrogen bonding, these characteristics are utilized to describe the interactions between solutes and solvents. Compressibility explains the qualitative intermolecular elastic forces that exist between the molecules of the solvent and the solute. The electrostatic field of ions has formed the basis for discussions on the structural arrangement of molecules in electrolyte solutions. The volumetric and thermoacoustic characteristics exhibit concentration‐dependent changes, suggesting the existence of molecular interactions in both systems. The vitamin B3 molecule shows stronger molecular contact at higher solvent concentrations, although it interacts most molecularly with MgCl2 solvents. This suggests that magnesium molecules are more suited for the attachment of vitamin B3 molecules than are water molecules. [ABSTRACT FROM AUTHOR]

Infrastructure and urbanization drive the increasing demand for concrete, which strains natural resources and threatens the ecosystem. Incorporating recycled materials into concrete can fulfill this demand without compromising quality. This study therefore examines the mechanical properties of concrete after replacing sand utilizing fine aggregates of brick powder (BP) using appropriate standard techniques of destructive and nondestructive testing methods. Concrete mixtures were developed by incrementally substituting sand with brick powder in ratios from 5% to 25% and evaluated for workability, compressive strength, and split tensile strength in comparison to conventional concrete. The findings indicate that replacing 10% sand with brick powder improves strength by 29.94%, reduces workability by 42.66%, and increases split tensile strength by 8.74%. A strong link was found between compressive strength, ultrasonic pulse velocity (UPV), and rebound number, which was confirmed by regression analysis. Integrating 10% brick powder improves concrete's mechanical properties and promotes sustainable construction practices. [ABSTRACT FROM AUTHOR]

Microwave-absorbing suspicious objects (MASOs) found using microwave-induced thermoacoustic imaging (MTI) can be divided into two types—endogenous (such as tumors or hematoceles) and exogenous (such as calculi or foreign bodies). These have different microwave absorption or ultrasonic velocity than normal human tissue, so MTI is efficient in detecting these anomalies. However, the existing MTI techniques can only reflect morphological information, making it difficult to distinguish the type of each anomaly. In this paper, a newly enhanced MTI system composed of a multiple-element ring transducer and a parallel data acquisition system (DAS) is presented. By using ultrasonic velocity and microwave absorption measurements, where the ultrasonic velocity is mainly used as an additional parameter to reflect mechanical characteristics, the type of the detected anomaly can be identified. In our experiments, the MASO can be located through the absorption difference detected by MTI. Due to the use of multiple-element transducers and a parallel DAS, the raw data can be acquired within about 20 ms for a two-dimensional image. Additionally, the ultrasonic velocity of the MASO can be calculated from the time sequence diagram of ultrasound propagation with a maximum time error of 0.084 μs. Apart from distinguishing the type of the anomaly, the proposed ultrasonic velocity-assisted microwave-induced thermoacoustic imaging (US-MTI) system has other advantages, such as being noninvasive, and allowing rapid imaging and a large field of view, which make US-MTI a suitable modality for regular screening. [ABSTRACT FROM AUTHOR]

The structural, optical and acoustical properties of a polymer composite of sodium sulfate (Na2SO4) doped polyvinyl pyrrolidone (PVP) were studied. The simple chemical route method was utilized for the preparation of the polymer composite by varying the concentration of Na ions in the PVP. The pure 3% PVP solution was mixed with five different concentrations of Na2SO4 solutions in the ratio of 80:20. X-ray diffraction (XRD) spectra of PVP/Na2SO4 (1.0% of Na2SO4 in 3.0% of PVP) confirmed the crystalline nature of the PVP/Na2SO4 polymer composite. The identification of several chemical functional groups contained in the PVP/Na2SO4 was demonstrated by Fourier transform infrared (FTIR) spectroscopy. The FTIR showed the excellent interaction between the polymer (PVP) and the dopant Na2SO4. Optical studies were performed by utilizing a UV-visible absorbance spectrophotometer. The UV-VIS spectroscopy results indicated that absorption increased in an asymmetric manner and the absorption peak showed a red shift with increasing Na ions concentration in the host PVP. The optical band gaps (direct and indirect) were found to decrease with increase in Na ions concentration in the polymer due to increase in the density of localized states in the band-gap. The activation and Urbach energies were evaluated from the conductivity measurements and the absorption coefficient, respectively. Several acoustical parameters, viz. ultrasonic velocity, density, viscosity, adiabatic compressibility, intermolecular free length, acoustic impedance, and surface tension, were also computed. The ultrasonic velocity, acoustic impedance, density, viscosity, and surface tension of the polymer solutions were found to increase while the adiabatic compressibility and intermolecular free length decreased with the addition of increasing amounts of Na ions in PVP. [ABSTRACT FROM AUTHOR]

Given the growing importance of organic-rich shale as unconventional reservoirs, a thorough understanding of the elastic and anisotropic behavior of shales is of great concern. However, for lacustrine shales, the complex lithofacies assemblage with geological deposition makes it challenging. Four lithofacies (argillaceous, mixed, siliceous, and calcareous) are recognized for 40 lacustrine shale samples from Jurassic formation in Sichuan Basin on the basis of their mineral compositions. We perform ultrasonic velocity measurements on 40 pairs of shale plugs at varied confining pressures, attempting to uncover the controls on the anisotropic properties of different lithofacies. The experimental results reveal that the total porosity, clay, and organic matter would positively contribute to velocity anisotropy of Jurassic shales. Combined with microstructure and pressure-dependent velocity analysis, the preferred orientations of platy clay particles and lenticular kerogen, the development of clay pores along clay fabric, and the sub-parallel micro-cracks induced by hydrocarbon expulsion are treated to be the controlling mechanisms. We add the total porosity, clay content, and kerogen volume together, intending to distinguish the elastic and anisotropic properties of four lithofacies. Generally, argillaceous shales, the dominant lithofacies in Jurassic formation, could be characterized by the highest clay and total organic content (TOC), the lowest bedding-normal velocities, and the strongest velocity anisotropy. Finally, with the laboratory data, two rock-physics-driven exponential relationships are proposed to predict the P- and S-wave velocity anisotropy with the bedding-normal velocities. [ABSTRACT FROM AUTHOR]

This paper introduces a reliable laser ultrasonic technique without damage to the surface in the thermoelastic regime that provides a one-side access method for simultaneously determining the thickness and ultrasonic wave velocity by employing multiple wave modes. Initially, this study determines the optimal separated distance between two laser beams to achieve an effective signal-to-noise ratio of the employed wave modes. Subsequently, a pre-established ratio of 0.95 for the velocity of skimming longitudinal waves and longitudinal waves enables the simultaneous calculation using a combination of the skimming longitudinal wave, reflected shear wave, and mode-converted longitudinal wave in a single measurement. Experiments were carried out on various plane plates made of aluminium alloy 6061, ranging in thickness from 4 to 20 mm, demonstrating a high accuracy in thickness measurement, with a maximum absolute error of 0.05 mm. Compare the results of ultrasonic wave velocity measurements with theoretical calculations, the maximum absolute error is 32 m/s and 80 m/s for longitudinal wave and shear wave, respectively. [ABSTRACT FROM AUTHOR]

Large-scale storage of 'green' hydrogen is essential in our quest to transition to renewable energy sources and achieve the net-zero emission targets. As such, Underground Hydrogen Storage (UHS) in geological porous media, such as in depleted oil and gas fields or saline aquifers, provides a cost-effective solution to store such large volumes of hydrogen (H 2) to buffer seasonal fluctuations in renewable energy supply and demand. Due to the novelty of the topic, many research gaps persist, but we focus on H 2 transport characteristics in the subsurface, hydrogen recoverability during cyclic operations, chemical interactions, and acoustic velocity as an indicator of H 2 saturation. In this study, we investigate UHS using a triaxial core-flooding experiment to address the above-mentioned research gaps by replicating field operations in the laboratory setup at representative subsurface conditions. Unstable displacement due to immiscible two-phase flow led to early H 2 breakthrough at 18% of H 2 saturation, ultimate H 2 saturation of 36% and withdrawal efficiency of 78% during the first cycle. However, cyclic charging and discharging led to an eventual H 2 withdrawal efficiency as high as 95%. Observed chemical interactions during our 3-day experiments were negligible, but our results also indicated a strong potential for evaporation-induced salt precipitation after injection of dry H 2 gas, leading to decreased reservoir porosity and permeability over time. Our ultrasonic measurements confirmed the sensitivity of P-wave velocity to H 2 saturation, which decreased by 3.5% when the H 2 saturation increased to 36%. This indicates that H 2 plume and leaks in UHS should be possible to monitor using 4D seismic surveys. Our results help to better understand H 2 flow, storage, and transport during cyclic UHS. The results indicate that H 2 withdrawal efficiency increases as the UHS reservoir matures and provides evidence of a dry near-well zone and evaporation induced salt precipitation in a UHS reservoir. [Display omitted] • Early breakthrough of H 2 at 18% H 2 saturation led to ultimate H 2 saturation of 36% after injecting 1.2 pore volumes of H 2. • H 2 withdrawal efficiency increased from 78% in the first cycle to 95% in the fourth cycle. • H 2 was produced at 90% purity with water vapor contamination indicating evaporation of liquid water into gaseous H 2. • 3.5% reduction in P-wave velocity when the H 2 saturation inside the specimen increased to 36%. • Evidence obtained for a dry near-well zone and evaporation induced salt precipitation during cyclic operations. [ABSTRACT FROM AUTHOR]

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A suspended dense graded broken stone road foundation stabilized by cement is a commonly employed material in roadworks, which is vulnerable to harm caused by freezing and thawing processes. This investigation intends to evaluate the laboratory behavior and the characteristics of freezing and thawing process-induced deterioration in a broken stone road foundation stabilized by cement with suspended dense grading, employing mechanical examinations and acoustical methods. The rate of mass loss in the broken stone road foundation stabilized by cement progressively rises, and the rate of decline in the compressive strength could potentially intensify as freezing and thawing processes augment. The modulus of resilience diminishes as freezing and thawing processes progress, and ultrasonic wave velocity also decreases. The patterns of mass loss, compressive strength decline, resilience modulus reduction, and ultrasonic wave velocity alteration adhere to a parabolic fitting relationship with freeze–thaw cycles, with an R2 above 0.95. The curves depicting the relationship of mass, compressive strength, resilience modulus, and ultrasonic wave velocity exhibit a steeper trend significantly after 10–15 cycles, which can be ascribed to the emergence of microcracks and the progression of flaws within the material. The evolution of damage in the broken stone road foundation stabilized by cement is monitored to progress through three distinct stages based on acoustic emission: initial, stationary, and failure. As freezing and thawing processes accumulate to 20 cycles, the length of initial phase correspondingly rises to three times, the length of failure stage diminishes to about one fifth. [ABSTRACT FROM AUTHOR]

Infrastructure and urbanization drive the increasing demand for concrete, which strains natural resources and threatens the ecosystem. Incorporating recycled materials into concrete can fulfill this demand without compromising quality. This study therefore examines the mechanical properties of concrete after replacing sand utilizing fine aggregates of brick powder (BP) using appropriate standard techniques of destructive and non-destructive testing methods. Concrete mixtures were developed by incrementally substituting sand with brick powder in ratios from 5% to 25% and evaluated for workability, compressive strength, and split tensile strength in comparison to conventional concrete. The findings indicate that replacing 10% sand with brick powder improves strength by 29.94%, reduces workability by 42.66%, and increases split tensile strength by 8.74%. A strong link was found between compressive strength, ultrasonic pulse velocity (UPV), and rebound number, which was confirmed by regression analysis. Integrating 10% brick powder improves concrete's mechanical properties and promotes sustainable construction practices.

Ammonium bromide, a water-soluble wood preservative used in pharmaceutical preparations, is the focus of this economic study aimed at understanding its physical properties in aqueous solutions. A straightforward and reliable method for examining interactions between molecules in liquids and solutions is ultrasonic research. When ultrasonic waves pass through liquids, they disturb the equilibrium between the molecules of the solute and solvent. Ion-ion and ion-solvent interactions are just two aspects of solvation chemistry that ultrasonic velocity measurement can elucidate. This study investigates the hydration number of aqueous solutions of ammonium bromide at temperatures ranging from 35 to 55°C, assessing both density and ultrasonic velocity across various concentrations. From the adiabatic compressibility, the hydration number and related parameters are derived, all of which are sensitive to changes in concentration and temperature. Thus, we explore how these parameters vary with changes in temperature and concentration, providing insight into the interactions of ions and molecules in the solutions, as well as their molecular structure.

The density (d), ultrasonic velocity (U), and viscosity (η) have been measured for the electrolytes, i.e., potassium chromate, sodium chromate, and sodium thiosulphate in an aqueous solution of dimethyl sulphoxide (DMSO) solution at 293 K, 298 K, 303 K, 308 K, and 313 K. By using the measured data, the other parameters like adiabatic compressibility (β), relative change in adiabatic compressibility (Δβ/β),change in adiabatic compressibility (Δβ),apparent molal volume (Øv), apparent molal compressibility (Øk),intermolecular free length (Lr), specific acoustic impedance (Z), limiting apparent molal compressibility ( ∅ k 0 ), limiting apparent molkal volume (Øv0) and their constants (Sk, Sv) can be calculated. The results obtained from the above parameters are helpful to determine the solute–solute and solute–solvent interaction. [ABSTRACT FROM AUTHOR]

\nHighlightsThe present work includes non-destructive evaluation of mechanical, thermal and ultrasonic properties of inorganic semiconducting wurtzite gallium selenide (w-GaSe) material using Lenard Jones’s potential approach at different temperatures. For elastic and mechanical properties, second-order elastic constants (SOECs), elastic moduli, anisotropy factors are estimated within the temperature range of 300-1500K. The ultrasonic and thermo-physical properties are calculated within the same temperature range utilising estimated SOECs, density and lattice parameters of the chosen material. The elastic, mechanical, and ultrasonic properties of the chosen semiconducting material have been found to decrease with an increase in temperature. The obtained results have been compared and analysed for justification and to explore the inherent properties of GaSe for semiconductor manufacturing industries. Evaluation of lattice parameters, density, elastic constants, ultrasonic velocity, Debye average velocity, Debye temperature, specific heat, thermal energy density, thermal conductivity and thermal relaxation time of w-GaSe at 300-1500K.Elastic constants, ultrasonic velocities and Debye temperature of w-GaSe decay with increase in temperature.Specific heat and thermal energy density are found to increase with increase in temperature for w-GaSe.The re-establishment time for thermal phonons reduces with temperature.The ultrasonic attenuation due to phonon-phonon interaction in w-GaSe will decrease with temperature.Evaluation of lattice parameters, density, elastic constants, ultrasonic velocity, Debye average velocity, Debye temperature, specific heat, thermal energy density, thermal conductivity and thermal relaxation time of w-GaSe at 300-1500K.Elastic constants, ultrasonic velocities and Debye temperature of w-GaSe decay with increase in temperature.Specific heat and thermal energy density are found to increase with increase in temperature for w-GaSe.The re-establishment time for thermal phonons reduces with temperature.The ultrasonic attenuation due to phonon-phonon interaction in w-GaSe will decrease with temperature. [ABSTRACT FROM AUTHOR]

The skeleton dense graded cement-stabilized crushed stone base is a widely used material for road construction. However, this material is susceptible to freeze–thaw damage, which can lead to degradation and failure, for which there is still a lack of an in-depth understanding of the freeze–thaw damage characteristics. This study aims to assess the mechanical performance and the freeze–thaw damage characteristics of the cement-stabilized crushed stone base with skeleton dense gradation based on a mechanical test and acoustic technology in a laboratory. There is a gradually increasing trend in the mass loss rate of the base material with an increase in freeze–thaw cycles. The curve steepens significantly after 15 cycles, following a parabola-fitting pattern relationship. The compressive strength of the cement-stabilized crushed stone base also decreased with a parabola-fitting pattern, and the decrease rate may accelerate as the freeze–thaw cycles increase. The resilience modulus of the base material decreased with increasing freeze–thaw cycles, following a parabolic trend. This suggests that the material's resistance to freeze–thaw damage decreases with increasing cycles. The ultrasonic wave velocity decreased with increasing freeze–thaw cycles, exhibiting a parabolic trend. This decline can be attributed to microcracks and defects developing within the material, offering insights for monitoring and predicting its service life. The damage progression of the cement-stabilized crushed stone base was found to occur in three stages: initial, stationary, and failure. The duration of stage I increased with freeze–thaw cycles, while the duration of stage III decreased. The findings provide valuable insights into the mechanisms and processes of freeze–thaw damage in a cement-stabilized crushed stone base with skeleton dense gradation. [ABSTRACT FROM AUTHOR]

This study aims to investigate the compressive strengths, ultrasonic pulse velocity, calorimetric, microstructural and rheological properties of calcined laterite-based geopolymer materials. Calcined laterite has been used as an iron-rich aluminosilicate and the hardener containing various molar ratios SiO2/Na2O such as 1.6, 1.8, 2.0 and 2.2 have been used for the preparation of geopolymer materials. The 28-days compressive strengths of the geopolymer materials using sodium waterglass containing molar ratios SiO2/Na2O equal to 1.6, 1.8, 2.0 and 2.2 are 49.98, 48.19, 46.65 and 9.35 MPa, respectively. Their maximum ultrasonic pulse velocities are 3200, 2800, 2000 and 1600 m/s, respectively. Their total heat flows are 85.91, 68.42, 18.50 and 16.34 J/g, respectively. The rheological properties of the geopolymer materials indicate the destruction of the flocculation and the homogenization of the particles of calcined laterite during the formation of the fresh geopolymer prepared using hardeners containing the molar ratios SiO2/Na2O equal to 1.6, 1.8 and 2.0. The one from molar ratio SiO2/Na2O equal to 2.2 contains more flocculation and therefore inhibits the geopolymerization process. It was found that the compressive strengths decrease with decreasing the amorphous phase content, the ultrasonic pulse velocities, total heat flow and corroborate the rheological properties of calcined laterite-based geopolymer materials. [ABSTRACT FROM AUTHOR]

The study investigates the theoretical velocities of binary liquid mixtures comprising Aniline and Benzene under 2MHz ultrasonic waves at temperatures of 303.15K, 308.15K, and 313.15K, examined in relation to mole fraction. Experimental data is compared with various theoretical models, including Nomoto theory (NOM), Ideal mixing relation (IMR), Impedance Relation (IR), Rao's Specific Velocity Method (R), and Junjie's relations (JR). The work reflects the changes in refractive index with varying liquid density across different mole fractions, explaining observed impacts on ultrasonic velocities. To assess the goodness of fit, Chi-square tests and average percentage errors are employed, allowing for an evaluation of the relative applicability of these theories within the studied systems. The study also explores how the thermos-acoustical characteristics of the systems evolve concerning the mole fraction of a common molecule, shedding light on molecular interactions. Furthermore, various parameters for the binary mixture, such as discrepancies in ultrasonic velocity, excess isentropic compressibility, surplus acoustic impedance, excess intermolecular free length, and molar refraction deviation, are computed using experimental data of density, refractive index, and ultrasonic velocities at different mole fractions of benzene in the aniline-benzene mixture. These calculations serve to reflect the intermolecular interactions present in the binary liquid mixture. [ABSTRACT FROM AUTHOR]

Sulfate attack seriously affects the durability of concrete structures, and many tunnels constructed in China in the early years did not adequately take it into account, resulting in structural degradation of many currently operating tunnels within their service life. In this study, we integrated experimental and machine learning (ML) approaches to assess tunnel concrete. Specifically, we compared concrete deteriorated by sulfate attack with freshly poured lining concrete that was built using the same mix ratio. By analyzing ultrasonic velocity data for different periods in wet and dry cyclic accelerated erosion experiments, we evaluated the effectiveness of multiple time series statistical methods, ML techniques, and their optimization algorithms. Through the analysis, we derived the best prediction model Particle Swarm Optimization - Long Short Term Memory (PSO-LSTM) and its Markov-corrected prediction results. Based on the damage time nodes of concrete compressive strength corrosion resistance coefficient (CCSCRC) and its actual damage in the test, the damage nodes of the target lining concrete of the existing tunnel are predicted. The experimental results show that: (1) The PSO-LSTM model is well adapted to the prediction of the deterioration data for concrete subjected to sulfate attack, with a model correlation coefficient R2 of 0.9739. (2) The PSO-LSTM model corrected by Markov chain can effectively capture the trend of the predicted data of concrete subjected to sulfate attack and improve the prediction accuracy. (3) When the CCSCRC decreased to 82 %, the loosening and granulation of the tunnel concrete occurred. In addition, actual failure of the concrete structure was observed at 677.6 days after sampling, less than two years. The outcomes of this research enhance the precision in predicting the service life of tunnel linings subjected to sulfate attack, providing valuable insights for on-site maintenance and construction, and contributing as a reference for similar studies.

The non-destructive characterization of ultrasonic properties in mixtures of vegetable oils with similar dominant chemical compositions is becoming increasingly important for various applications. The combination of ultrasonic wave reflection as an experimental method and the partial least squares statistical method has been employed to establish reference graphs and models for detecting adulterated oils. This experimental study focuses precisely on measuring the attenuation and ultrasonic velocity of mixtures of organic argan oil with volumetric fractions of sesame oil, peanut oil or argan oil extracted from kernels depulped by goats. The measurements exhibit distinct behaviors manifested by electrical signals for the mixture obtained after the addition of each volumetric fraction, reflecting the capability of the adopted method to detect this difference. A notable decrease in ultrasonic velocity is observed in the mixtures as the quantity of added oil increases, with a maximum variation of 11 m/s for the argan/peanut oil mixture. Conversely, The attenuation of ultrasonic waves increases proportionally with the added volumetric fractions, with the argan/peanut oil mixture exhibiting an attenuation variation range of 3.57 Np/m. Prediction models for the added volumetric fractions to organic argan oil based on attenuation and ultrasonic velocity, showed a weak correlation between the predicted quantity of added oil and the actual quantity added to organic argan oil, with determination coefficients (r2) not exceeding 65%. The weak correlation is due to the similar chemical compositions of the oils. These results underscore the value of ultrasonic-statistical analysis for authenticating and ensuring the quality of vegetable oils. However, the limitations highlight the need to refine models for better accuracy. This method can verify oil authenticity in the food industry, ensuring consumer protection and quality standards. Additionally, it offers a quick and simple alternative to traditional methods, reducing costs and improving efficiency in quality control processes.

Abstract Ultrasonic techniques are frequently used in organic molecule conformation analysis. Mixtures of ternary liquid complexes are extensively used for comprehending the strength as well as the characteristics of the interactions between molecules. Experimentally, the thermo physical properties of ternary liquid mixtures such as viscosity (η), density (ρ) and velocity (u) of K-contin, (2-Aminoacetamido)acetic acid and non-aqueous medium were determined over temperature ranges of 298.15, 308.15 and 318.15 K. The experimental data were used to ascertain the thermoacoustic parameters such as free volume, internal pressure, adiabatic compressibility, solvation number, specific acoustic impedance and intermolecular free length. These parameters are more useful for predicting and validating molecular interactions.

Microwave-absorbing suspicious objects (MASOs) found using microwave-induced thermoacoustic imaging (MTI) can be divided into two types—endogenous (such as tumors or hematoceles) and exogenous (such as calculi or foreign bodies). These have different microwave absorption or ultrasonic velocity than normal human tissue, so MTI is efficient in detecting these anomalies. However, the existing MTI techniques can only reflect morphological information, making it difficult to distinguish the type of each anomaly. In this paper, a newly enhanced MTI system composed of a multiple-element ring transducer and a parallel data acquisition system (DAS) is presented. By using ultrasonic velocity and microwave absorption measurements, where the ultrasonic velocity is mainly used as an additional parameter to reflect mechanical characteristics, the type of the detected anomaly can be identified. In our experiments, the MASO can be located through the absorption difference detected by MTI. Due to the use of multiple-element transducers and a parallel DAS, the raw data can be acquired within about 20 ms for a two-dimensional image. Additionally, the ultrasonic velocity of the MASO can be calculated from the time sequence diagram of ultrasound propagation with a maximum time error of 0.084 μs. Apart from distinguishing the type of the anomaly, the proposed ultrasonic velocity-assisted microwave-induced thermoacoustic imaging (US-MTI) system has other advantages, such as being noninvasive, and allowing rapid imaging and a large field of view, which make US-MTI a suitable modality for regular screening.

Elastic wave velocities of compressional and shear waves propagating through sedimentary rocks are often coupled with information of bulk density to derive the rock stiffness. Acquiring the transit time of compressional and shear waves often involves manual picking of wave arrival times from wave trains recorded in the laboratory or by well‐logging tools. Picking the compressional wave arrival time is commonly accepted as straightforward. Oppositely, detecting the shear wave arrival and picking its arrival time is often troublesome because the transmitted shear wave partly converts to compressional waves and back to a secondary shear wave, concealing the transmitted shear wave arrival in the wave train. In laboratory settings, we illustrate the difficulty of shear wave detection in wave trains recorded on highly porous chalk plug samples from the Danish North Sea Basin. Wave trains were recorded on plugs dry, Tap‐water or Isopar‐L saturated during uniaxial strain compaction. The recorded shear wave trains showed two distinct features, which could be interpreted as the transmitted shear wave first arrival; we denoted them as early and late arrivals. However, as only one feature can mark the arrival of the transmitted shear wave, we propose a semi‐empirical disclosure strategy combining a graphical representation of stacked wave trains with rock physical modelling. By stacking recorded wave trains in a graphical strain–time–amplitude domain, we demonstrate that an early shear wave feature marks a converted shear to compressional to shear wave and not the transmitted shear wave. We used physical modelling to identify early shear wave features and illustrate the consequences of adopting a falsely interpreted shear wave on stiffness properties. [ABSTRACT FROM AUTHOR]

The non‐destructive ultrasonic technique is a great employ for knowing the solute–solvent interaction in the polymer blend. By the ultrasonic velocity and attenuation evaluation, the visco‐elastic behaviors of the polymer solution have been assessed and compared with the results of conventional dynamic mechanical analysis. In the present research work, a comprehensive ultrasonic investigation of molecular interaction in a polymeric mixture of Poly (ethylene oxide) PEO and dimethyformamide (DMF) at 333 K has been executed by using the information provided by the literature. For this purpose, ultrasonic waves of two different frequencies such as 2 and 5 MHz have been implemented. Several acoustical parameters such as adiabatic compressibility, acoustic impedance, relaxation time, and ultrasonic attenuation coefficient (훼/푓2) are explored. Thermodynamic parameters like relative association and intermolecular free path length are also estimated. The evaluated values have been associated with the previous experimental results. The non‐ideal approach of the solution is analyzed and discussed in detail. [ABSTRACT FROM AUTHOR]

Ultrasonic methods have been very fruitful in studying the physical properties of binary liquid combinations. In this present study, the thermoacoustic behavior of benzyl propionate with dimethyl sulfoxide (DMSO) is observed using ultrasound, density, and viscosity at different temperatures between 308 and 328 K with a phase of 10 °C. Benzyl propionate is a sweet‐smelling liquid that is used in the botanical and fruit fragrance industries, as well as in the flavoring of organic products. DMSO is a dipolar aprotic, naturally soluble compound used for slow drug synthesis, device synthesis, and drug delivery to the body. Estimated values such as adiabatic compressibility, intermolecular free length, internal pressure, and free volume are determined from arbitrary ultrasonic velocity, density, and viscosity data. The same excess parameters of adiabatic compressibility, intermolecular free length, internal pressure, and free volume support finding the nature of the reaction. The sort of interactions has been accounted for utilizing these qualities. In the present work, benzyl propionate with dimethyl sulfoxide has been characterized by using ultrasonic waves and since this wave is a well‐known tool for NDT, so the mixture is properly characterized. These thermoacoustic parameters with different concentrations of DMSO at different temperatures have been used to study the complex formation and binding through intermolecular forces. [ABSTRACT FROM AUTHOR]

Experimental ultrasonic velocities of binary liquid mixture of acetone and carbon tetra chloride at temperatures 286.15 K, 289.15 K and 293.15 have been evaluatedat 2 MHz as a function of molar concentrations. The experimental values were compared with various theories for analysis of ultrasonic velocity in binary liquid mixtures such as Nomoto theory (NOM), ideal mixing relation (IMR) of Van Dael andVangeel, Impedance Relation (IDR), Rao's Specific Velocity Method (Rao) and Junjie's relations (JR). Chi-square test and average percentage error were applied to investigate the relative applicability of these theories to the present systems. The variation of thermo acoustical parameters of the systems with the mole fraction has been discussed in term of molecular interactions. [ABSTRACT FROM AUTHOR]

Investigation of variations in rheological, acoustical and electrical properties of an eco-friendly nanofluids could be a substitute for a coolant/lubricant, in industry 4.0. Researchers in the past two decades have shown a greater interest in exploring the experiential changes of nanofluid based on volume fraction, and temperature suitable for a desired application. The present study observes, the influences of volume fractions of CuO nanoparticles in enriched coconut oil (CO) blended with Moringa oleifera seed oil (MOSO) (3:1). The surface morphology of CuO nanoparticles shows the average particle sizes are in between 11 nm and 70 nm. The X-ray diffraction showed a monoclinic structure without impurities which having crystallite size of 23 nm. Physical properties such as viscosity, shear rate, shear stress, torque and density were observed for the stable nanofluid at three different volume fractions (φ = 0.4, 0.8, and 1.0). The viscosity of the prepared nanofluid was enhanced to 22.1% at φ = 1. Acoustical behaviour was probed to estimate the decrease in ultrasonic wave transmission through nanofluid with upsurge in φ and a novel model equation (with R2 = 0.983) was developed. As an additional application, the defects in machines can be validated with an aid of ultrasonic velocity. The response of dielectric constant (DC) with φ and sustainability is in the range of 2.65–3 at 90 °C supports the usage of nanofluids in energy storage system and a replacement of transformer oil. [ABSTRACT FROM AUTHOR]

Demolition of buildings can generate large amounts of waste concrete, which if used effectively, can help reduce both the extraction of raw materials and carbon emissions. However, the presence of old cement mortar affects the effective use of waste concrete as a recycled fine aggregates. This study aims to remove old mortar adhering to the surface of waste concrete coarse aggregates via thermal-physical treatment. This study involves assessing the thermal-physical treatment technology and comparing the performance of recycled fine aggregates prepared using this technology with that of fully recycled fine aggregates. The results of this study illustrate the effect of the thermal-physical treatment technique on the preparation of recycled fine aggregates from waste concrete and the effect of fully recycled fine aggregates and recycled fine aggregates prepared using this technique on ceramsite concrete. The results revealed that the thermal-physical treatment technology has a positive effect in improving the quality of recycled fine aggregates prepared via the thermal-physical treatment technique. This technique helps to significantly improve the compressive strength, ultrasonic velocity, resistance to sulfate attack, and microstructure of the recycled ceramsite concrete compared with the fully recycled fine aggregate. [ABSTRACT FROM AUTHOR]

Considering the gradual reduction of fossil fuel resources and their role in environmental issues, biodiesel-derived products have received much attention as fuel additives to enhance their properties and reduce emissions. The present work reports the engine performance and emission characteristics for a fuel blend consisting of solketal, a derivative of glycerol and gasoline. In this study, 5–10 vol% solketal was mixed with gasoline by ultrasonic processor to prepare a solketal-gasoline fuel blend. The blending of additives will affect the volumetric transport properties as well as the combustion quality of the fuel. Some important properties like thermal conductivity, surface tension, adiabatic compressibility, relative association, and intermolecular free path length were measured at different temperatures by measuring the ultrasonic velocity in the fuel blend. Four-stroke SI engine performance was studied in terms of brake-specific fuel consumption (BSFC) and brake thermal efficiency (BTE). BSFC increases by 15%, and BTE shows a marginal reduction of about 5.39% at 28.13 N·m torque with a 10% solketal-gasoline blend. The exhaust analysis indicates that CO emissions decrease and NOx and CO2 increase compared to pure gasoline as fuel, the brake thermal efficiency indicates a marginal reduction of about 5.39% for 10% solketal. [ABSTRACT FROM AUTHOR]

Ultrasonic techniques are frequently used in organic molecule conformation analysis. Mixtures of ternary liquid complexes are extensively used for comprehending the strength as well as the characteristics of the interactions between molecules. Experimentally, the thermo physical properties of ternary liquid mixtures such as viscosity (η), density (ρ) and velocity (u) of K-contin, (2-Aminoacetamido)acetic acid and non-aqueous medium were determined over temperature ranges of 298.15, 308.15 and 318.15 K. The experimental data were used to ascertain the thermoacoustic parameters such as free volume, internal pressure, adiabatic compressibility, solvation number, specific acoustic impedance and intermolecular free length. These parameters are more useful for predicting and validating molecular interactions. [ABSTRACT FROM AUTHOR]

Nanoparticles suspended in conventional fluids also named as nanofluids are being researched due to its unique thermal behaviour and its employability as heat transfer fluids. This report details the preparation and stabilization of Al2O3/CuO nanofluids and was analyzed by X-Ray diffraction, SEM and IR respectively. Further the synthesized nanoparticles are dispersed in different volume fractions of ethylene glycol solvent (0.001, 0.003, and 0.005 mass fractions) to prepare nanofluids. The nanofluids were prepared via rigorous stirring and ultrasonic agitation to maintain the stability. Further these nanofluids were prepared without any stabilizer at 2.7 pH. Further the thermal properties were investigated using KD2 Probe analysing unit, which showed that the thermal conductivity increased with higher concentrations of nanofluids. Ultrasonic velocity, yet another property of nanofluids, represents the speed in which sound propagates in a material and depends on density and elasticity of the material. Ultrasonic velocity of nanofluids is important for non-radiative and non-destructive structural analysis and hence the same has been investigated. Results proved that the prepared nanocoolants are stable and hence could be utilized for coolant applications.

Ultrasonic velocity measurements are used to elucidate various aspects of solvation chemistry, including solute–solute and solute–solvent interactions. Herein, an attempt is made to study a behavior of two sweeteners, D-fructose and D-sorbitol, in aqueous and non-aqueous media was attempted. D-fructose is a simple sugar found in many foods and can be consumed by diabetics and people suffering from hypoglycemia. D-Sorbitol is a sugar substitute used in diet foods, sugar-free chewing gum, mints, cough syrups, mouthwash, toothpaste etc., D-sorbitol is an excellent humectant and texturizing agent that is also used in other products such as pharmaceuticals and cosmetics. The interactions between the solute and solvent molecules are explained in terms of the solvation numbers of both aqueous and non-aqueous solutions of D-fructose and D-sorbitol. The viscosity study correlates the viscosity of the solution with solvation; here, density, ultrasonic velocity, and viscosity of aqueous and non-aqueous solutions at various concentrations are measured at different temperatures ranging from 35 to 55 °C. These parameters provide sufficient information on the interaction between molecules that may aid chemists in analyzing the mechanisms of the behavior of D-fructose and D-sorbitol in water and the water–ethanol medium through which they are consumed. The Fourier transforms infrared spectra of pure solvent, salt, and their solutions were recorded and analyzed for confirmation.

A suspended dense graded broken stone road foundation stabilized by cement is a commonly employed material in roadworks, which is vulnerable to harm caused by freezing and thawing processes. This investigation intends to evaluate the laboratory behavior and the characteristics of freezing and thawing process-induced deterioration in a broken stone road foundation stabilized by cement with suspended dense grading, employing mechanical examinations and acoustical methods. The rate of mass loss in the broken stone road foundation stabilized by cement progressively rises, and the rate of decline in the compressive strength could potentially intensify as freezing and thawing processes augment. The modulus of resilience diminishes as freezing and thawing processes progress, and ultrasonic wave velocity also decreases. The patterns of mass loss, compressive strength decline, resilience modulus reduction, and ultrasonic wave velocity alteration adhere to a parabolic fitting relationship with freeze–thaw cycles, with an R2 above 0.95. The curves depicting the relationship of mass, compressive strength, resilience modulus, and ultrasonic wave velocity exhibit a steeper trend significantly after 10–15 cycles, which can be ascribed to the emergence of microcracks and the progression of flaws within the material. The evolution of damage in the broken stone road foundation stabilized by cement is monitored to progress through three distinct stages based on acoustic emission: initial, stationary, and failure. As freezing and thawing processes accumulate to 20 cycles, the length of initial phase correspondingly rises to three times, the length of failure stage diminishes to about one fifth.

The unfrozen water content (UWC) of rocks at low temperature is an important index for evaluating the stability of the rock engineering in cold regions and artificial freezing engineering. This study addresses a new method to estimate the UWC of saturated sandstones at low temperature by using the ultrasonic velocity. Ultrasonic velocity variations can be divided into the normal temperature stage (20 to 0 ℃), quick phase transition stage (0 to −5 ℃) and slow phase transition stage (−5 to −25 ℃). Most increment of ultrasonic velocity is completed in the quick phase transition stage and then turns to be almost a constant in the slow phase transition stage. In addition, the UWC is also measured by using nuclear magnetic resonance (NMR) technology. It is validated that the ultrasonic velocity and UWC have a similar change law against freezing and thawing temperatures. The WE (weighted equation) model is appropriate to estimate the UWC of saturated sandstones, in which the parameters have been accurately determined rather than by data fitting. In addition, a linear relationship between UWC and ultrasonic velocity is built based on pore ice crystallization theory. It is evidenced that this linear function can be adopted to estimate the UWC at any freezing temperature by using P-wave velocity, which is simple, practical, and accurate enough compared with the WE model.

A polemic is given regarding the apparent molar volumes used in examining the molecular interactions between the dissolved tetraalkylammonium iodide, R4NI, salts and organic solvents. The apparent molar volumes of the four R4NI salts dissolved in N,N-dimethylformamide, taken from the authors' earlier studies, were found to vary significantly from one study to another. [ABSTRACT FROM AUTHOR]

Ultrasonic velocity measurements are used to elucidate various aspects of solvation chemistry, including solute– solute and solute–solvent interactions. Herein, an attempt is made to study a behavior of two sweeteners, Dfructose and D-sorbitol, in aqueous and non-aqueous media was attempted. D-fructose is a simple sugar found in many foods and can be consumed by diabetics and people suffering from hypoglycemia. D-Sorbitol is a sugar substitute used in diet foods, sugar-free chewing gum, mints, cough syrups, mouthwash, toothpaste etc., D-sorbitol is an excellent humectant and texturizing agent that is also used in other products such as pharmaceuticals and cosmetics. The interactions between the solute and solvent molecules are explained in terms of the solvation numbers of both aqueous and non-aqueous solutions of D-fructose and D-sorbitol. The viscosity study correlates the viscosity of the solution with solvation; here, density, ultrasonic velocity, and viscosity of aqueous and nonaqueous solutions at various concentrations are measured at different temperatures ranging from 35 to 55 °C. These parameters provide sufficient information on the interaction between molecules that may aid chemists in analyzing the mechanisms of the behavior of D-fructose and D-sorbitol in water and the water–ethanol medium through which they are consumed. The Fourier transforms infrared spectra of pure solvent, salt, and their solutions were recorded and analyzed for confirmation. [ABSTRACT FROM AUTHOR]

The skeleton dense graded cement-stabilized crushed stone base is a widely used material for road construction. However, this material is susceptible to freeze–thaw damage, which can lead to degradation and failure, for which there is still a lack of an in-depth understanding of the freeze–thaw damage characteristics. This study aims to assess the mechanical performance and the freeze–thaw damage characteristics of the cement-stabilized crushed stone base with skeleton dense gradation based on a mechanical test and acoustic technology in a laboratory. There is a gradually increasing trend in the mass loss rate of the base material with an increase in freeze–thaw cycles. The curve steepens significantly after 15 cycles, following a parabola-fitting pattern relationship. The compressive strength of the cement-stabilized crushed stone base also decreased with a parabola-fitting pattern, and the decrease rate may accelerate as the freeze–thaw cycles increase. The resilience modulus of the base material decreased with increasing freeze–thaw cycles, following a parabolic trend. This suggests that the material’s resistance to freeze–thaw damage decreases with increasing cycles. The ultrasonic wave velocity decreased with increasing freeze–thaw cycles, exhibiting a parabolic trend. This decline can be attributed to microcracks and defects developing within the material, offering insights for monitoring and predicting its service life. The damage progression of the cement-stabilized crushed stone base was found to occur in three stages: initial, stationary, and failure. The duration of stage I increased with freeze–thaw cycles, while the duration of stage III decreased. The findings provide valuable insights into the mechanisms and processes of freeze–thaw damage in a cement-stabilized crushed stone base with skeleton dense gradation.

The detection of ductile damage by image-based methods is time-consuming and typically probes only small areas. It is therefore of great interest for various cold forming processes, such as sheet-bulk metal forming, to develop new methods that can be used during the forming process and that enable an efficient detection of ductile damage. In the present study, ductile damage in DC04 was examined using ultrasonic testing. First, different grain sizes were set by heat treatment. Subsequently, the sheet metal was formed by cold rolling. A clear correlation between the average void diameter and the measured ultrasonic velocity could be shown. The ultrasonic velocity showed a clear decrease when the average void size increased because of the increasing forming degree. The ultrasonic measurements were finally employed to calculate a damage parameter D to determine the amount of ductile damage in the microstructure for different grain sizes after cold rolling. [ABSTRACT FROM AUTHOR]

This article reports on the characterization of the "as-fabricated" state of Inconel 718 samples fabricated using laser directed energy deposition (DED). Laser-DED is known to produce complex metastable microstructures that can significantly influence the baseline ultrasonic response compared to conventional processing methods. The present work uses three parameters to characterize the samples: (a) ultrasonic velocity, (b) an attenuation coefficient, and (c) a backscatter coefficient. The baseline ultrasonic response from the DED sample was compared against the ultrasonic properties of conventional IN718 samples reported in the literature. The results suggest that strong grain boundary scattering from large macrograins can lead to attenuation and backscatter values that are significantly higher than conventional samples. Additionally, the results including velocities, attenuation and backscatter coefficients were found to be dependent on the fabrication direction, with the build direction being different from the transverse directions. Finally, destructive analysis was used to develop conjectures to explain the experimentally observed ultrasonic response. [ABSTRACT FROM AUTHOR]

The acoustical investigation of molecular interaction has been performed from the measurement parameters of ultrasonic velocity (U), density (?) and viscosity (Ｕ) of aqueous dextran solution at different temperatures. The thermodynamic and other allied parameters like internal pressure (pi), free volume (p), absorption coefficient or attenuation coefficient (a), Rao's constant (Ro) and Wada's constant (W) have been computed. To understand the structural reorganization of the solute (dextran) and solvent (distilled water) in aqueous solution, concentration and temperature changes of these parameters have been investigated. Differences in ultrasonic velocity and other factors are crucial to comprehending the solute-solvent intra and intermolecular interactions between the constituent molecules. [ABSTRACT FROM AUTHOR]

The crack closure, propagation, recovery, and damage characteristics of a granite undergoing uniaxial and triaxial compressive cyclic loading were investigated. The ultrasound speed was measured to quantify the damage and predict the failure of selected granite specimens. The results showed that with the increase of the stress amplitude, new cracks formed in the specimens. The average ratio of the crack recovery stress to the peak stress was greater than that of the crack closure stress, indicating that crack recovery was easier to achieve than crack closure. New cracks can form during unloading, causing the crack recovery strain to increase. In experiments, it was observed that with the increase in the number of cycles, the P-wave velocity differences increased at first, they then reached a steady value, and finally decreased. The ratio of the peak P-wave velocity to the peak S-wave velocity can be used as a precursor to failure, and an abrupt change in that ratio precedes a rock failure. Damage parameters based on crack recovery strain and wave velocity were identified. It was found that the growth rates of the damage parameters first increased and then remained unchanged with the increase in the number of cycles. In the cases of uniaxial cyclic loading and unloading, the results of the two damage parameters were approximately equal. Furthermore, under triaxial cyclic loading, the damage parameters based on wave speed were determined to be greater than those of the other damage parameters. [ABSTRACT FROM AUTHOR]