Ultrasonic Properties Research Articles

Ultrasonic Properties of Multi-material SS420-IN718 Structures Fabricated Using Laser Directed Energy Deposition

Ultrasonic Properties of Multi-material SS420-IN718 Structures Fabricated Using Laser Directed Energy Deposition

Evaluation of ultrasonic and mechanical methods for assessing dentin demineralization in children's permanent teeth in vitro

Relevance. With the advent of advanced methods for functional diagnostics, dentists have gained new opportunities for detecting carious lesions. However, the diagnostic sensitivity of these methods requires further investigation.Purpose. To evaluate the condition of intact and demineralized dentin in children's permanent teeth using both ultrasonic and mechanical methods.Materials and methods. Divided cross-section" models were created from premolars extracted from children for orthodontic purposes. After a 20-day exposure to a demineralizing buffer solution with a pH of 4.5, both the intact and demineralized dentin cross-sections were tested using ultrasonic and mechanical methods.Results. Statistically significant differences were observed in the mean ultrasonic signal speed C between two independent sample groups: intact dentin (Group 1) and demineralized dentin (Group 2), based on Mann-Whitney U-test calculations (p = 0.01). In Group 2, the mean value of C was 27% lower compared to Group 1. Additionally, significant differences were found in the mean ultimate strength σ between two independent groups: intact dentin (Group 3) and demineralized dentin (Group 4), with Group 4 showing a 29.5% reduction in the mean σ value, according to Mann-Whitney U-test calculations (p = 0.01).Conclusion. Demineralization leads to significant changes in both the ultrasonic and mechanical properties of dentin. Statistical analysis of the laboratory test results using the "divided cross-section" model supports the effectiveness and diagnostic sensitivity of the methods applied for evaluating the extent of dentin demineralization.

Investigation of structural, ultrasonic, and radiation shielding properties of PbO-B2O3 glasses reinforced MnO2

Glass composition systems of (65-x) B2O3+15 PbO +15 Na2O+ 5 Al2O3+ x MnO2, where x = 0, 0.1, 0.3 and 0.5 mol% were organized by the usual melting-annealing process. Electron spin resonance (ESR) displayed broad hyperfine before and after exposing glasses to 25 kGy of gamma radiation, while sharp ESR signals at magnetic field range 3200–3500 Gauss were detected after irradiating glasses with 50 kGy. FTIR and Raman spectroscopy displayed the high structural stability of the glasses towards 25 kGy of gamma radiation, signifying the central building units of various borate groups at the same intensities and positions. Different ultrasonic characteristics such as ultrasonic velocities, elastic properties, Poisson’s ratio, Lamé constants, acoustic impedance, and ultrasonic attenuation coefficient didn’t variate greatly with gamma radiation exposure to 25 kGy. Comparing results showed that 0.5 % MnO2 glass has the most stable structure against gamma irradiation, the lowest ultrasonic velocity and wave passage, and the highest attenuation of waves, ensuring the high ability of the prepared glasses to inhibit the echoes. Experimental shielding parameters such as mass (MAC) and linear attenuation coefficients (LAC), half value layer (HVL) and tenth value layer (TVL) were measured for gamma rays and removal cross section area was measured for neutrons. Theoretical studies by WinXcom program revealed satisfactory settlement, with the experimental examinations displaying a high efficiency of the glasses to shield gamma rays especially the glass with 0.5 % MnO2, which has the highest attenuation and the lowest HVL and TVL. Therefore, the high efficiency of the glasses to be used as radiation shielding applicants in radiation institutes before 50 kGy, i.e. as storage containers for radioactive wastes in nuclear medicine.

Effects of Plant Meristem-Cell-Based Cosmetics on Menopausal Skin: Clinical Data and Mechanisms.

A randomised open clinical/laboratory study was performed to evaluate the safety and cosmetic efficacy of facial cosmetics for females during the menopausal period. The cosmetics contain active ingredients of meristem cells derived from the medicinal plants Leontopodium alpinum, Buddeleja davidii, Centella asiatica, and Echinacea angustifolia. Recently, the major bioactive molecules of these medicinal plants (leontopodic acid, verbascoside, asiaticoside, and echinacoside, respectively) have been thoroughly evaluated in vitro for molecular pathways and cellular mechanisms and their preventive/curative effects on human skin cells exposed to factors promoting premature skin ageing and cellular senescence. Nevertheless, clinical data on their safety/efficacy to ageing human skin are scarce. This clinical study enrolled 104 Caucasian females in pre-menopause, menopause, or post-menopause periods. They applied cosmetic serums daily for 1 month. Questionnaires and instrumental and biochemical methods were used to assess dermatological/ophthalmological safety and cosmetic efficacy through changes of the skin physiology markers characteristic of ageing/menopause (elasticity, barrier functions, moisture, sebum, ultrasonic properties, and collagen content and structure). Quantitative microbiological tests were carried out for skin microbiota fluctuations. Data showed that the cosmetics were safe, and they shifted the skin physiology parameters to a younger biological age, enhanced collagen synthesis, inhibited lipid peroxidation, and favoured normal microbiota.

Electromagnetical and ultrasonic characterizations of concretes subjected to internal swelling reactions

Among pathologies of reinforced concrete structures, internal swelling reactions (ISR), including alkali-aggregate reaction and delayed ettringite formation, are at the origin of cracks and major disorders due to rebar corrosion. Visual evaluation of crack density combined to non-destructive testing techniques can be used to characterize the global swelling and then give some structural diagnosis. For the last ones, an intermediate step (assimilated to a calibration step) can be performed at laboratory to evaluate the sensitivity of electromagnetic, electrical and ultrasonic properties of concretes subject to ISR.This present study focuses on such characterizations of concrete samples presenting different levels of ISR and for several water content. Numerous samples have been extracted from mock-ups representative of two massive concrete structures, affected one by alkali-aggregate reaction and the other by delayed ettringite formation, and conditioned in homogeneous and controlled conditions. After describing the experimental campaign, results are shown and commented.

Pulse echo method for characterizing the ultrasonic properties of argan oil compared to vegetable oils with similar fatty acid profiles

Abstract 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.

Ice matrix composites for Cryo-ultrasonic testing

Cryo-ultrasonic testing utilizes polycrystalline ice coupling to enable the inspection of metallic components with complex shape. The relatively high velocity of compressional waves in ice (approximately 4000 m s−1) and its ability to support the propagation of shear waves, significantly strengthen the ultrasonic transmission through curved interfaces over conventional water coupling. This paper explores the possibility of further enhancing the ultrasonic properties of ice by dispersing solid particles in water before it is frozen. Complex physicochemical phenomena occur when aqueous dispersions freeze which can lead to a solid material with microstructural characteristics that may be unfavorable to the propagation of ultrasonic waves. Here, these effects are controlled to produce a composite material consisting of alumina nanoparticles in an ice matrix. The composite exhibits compressional and shear wave velocities of approximately 4800 m s−1 and 2700 m s−1 , respectively. Importantly, the mass density of the material is more than twice as large as the density of water. Finally, it is shown that a phenomenon similar to a glass transition occurs during freezing which results in low ultrasonic attenuation when the temperature approaches – 100 °C.

A Study on the Development of the Stainless Steel Tube Bundle Structure Detecting System Using Ultrasonic Guided Wave.

In this study, an ultrasonic guided wave system that can be used to detect broken tubes in stainless steel tube bundle structures (e.g., heat exchangers) with fairly narrow spacing between the tubes was designed. The interval between the tubes was 1.5 mm, and the thickness of the strip with a transducer that can be inspected by passing between the tubes was designed to be 1 mm. The damaged specimen was filled with water, and it was confirmed that the signal amplitude was smaller than that of the normal specimen filled with air. The ultrasonic properties of stainless steel were analyzed using the developed system, and it is expected that this will contribute to breakage inspection for tube bundles with narrow spacing.

Effect of triazolium-based ionic liquid (1, 4-dimethyl- 4H-1, 2, 4-triazolium iodide) on volumetric and ultrasonic properties of binary aqueous solutions of benzamide/benzylamine: experimental and computational study

ABSTRACT In the current investigation, effect of triazolium-based ionic liquid 1, 4-Dimethyl- 4 H-1,2,4-triazolium iodide (DMTI) on volumetric and ultrasonic properties of binary aqueous solutions of benzamide/benzylamine is analysed at four equidistant temperatures and atmospheric pressure. Molecular interactions of DMTI in binary aqueous solutions of benzylamine/benzamide are also interpreted using density (ρ) and speed of sound (u) data along with FT-IR measurements. Different volumetric and ultrasonic parameters were also computed by employing the experimental values of density (ρ) and speed of sound (u), and are further used to elucidate various kinds of interactions in the ternary system. Volumetric and acoustic transfer parameters were further used for the computation of interaction coefficients (pair and triplet). To analyse the outcomes of the estimated parameters, spectroscopic and density-functional theory (DFT) investigations have also been carried out.

Relating the ultrasonic and aerosol filtration properties of filters

Non-contact methods are useful to improve the quality control of particle filtration media. The purpose of this paper is to investigate the correlation between the filtration efficiency of a porous sheet and its ultrasonic properties obtained using a non-contact technique. An air-coupled ultrasonic technique is used to obtain rapid measurements without affecting the integrity of the material. High frequencies (from 0.1 to 2.5 MHz) are used to improve technique sensitivity, and transmitted waves are measured to probe the internal properties of the material. Measurements of transmission coefficient spectra (amplitude and phase) and the corresponding ultrasound velocity and attenuation coefficient at different frequencies are obtained for a set of filtration media with well-characterized properties. Results show that the ultrasonic properties of filtration media vary as a function of basis weight, and therefore filtration efficiency, for a given charge state. However, the effect of electrostatic charge on ultrasonic propagation is almost negligible, as expected. We conclude that ultrasonic transmission may provide a valuable tool for the continuous online monitoring of material quality during fabrication and as a method to tease apart mechanical and electrostatic contributions to particle filtration.

A do it yourself (DIY) point-of-care wrist ultrasound phantom for joint access training

BackgroundJoint access is essential for arthrocentesis, or joint aspiration of fluids. Joint treatments that are not performed properly can result in avoidable patient issues such as damage to the muscles, tendons, and blood vessels surrounding the joint. The use of ultrasound has become the gold standard for this procedure and proven to be a support in the skill learning process. However, success with this equipment, particularly in small joints like the wrist, depends on a clinician's capacity to recognize the crucial landmarks that guide these procedures. Prior to executing on a real patient, task trainers have proven to be an effective way for doctors to practice and prepare for procedures. However, shortcomings of current solutions include high purchase costs, incompatibility with ultrasound imaging, and low reusability. In addition, since this is a procedure that is not performed frequently, there may not be space or resources available in healthcare facilities to accommodate one at the point of care. This study aimed to close the existing gap by developing a DIY ultrasound compatible task trainer for wrist joint access training.ResultsWe developed a novel ultrasound compatible wrist joint model that can be made from sustainable materials and reusable parts, thus reducing the costs for acquisition and environmental impact. Our model, which was produced utilizing small-batch production methods, is made up of 3D-printed bones enclosed in an ultrasound-compatible gelatin mixture. It can be easily remade after each practice session, removing needle tracks that are visible under ultrasound for conventional phantoms. The ultrasonic properties of this model were tested through pixel brightness analysis and visual inspection of simulated anatomical structures.ConclusionOur results report the advantages and limitations of the proposed model regarding production, practice, and ultrasound compatibility. While future work entails the transfer to patients of the same skill, this reusable and replicable model has proven, when presented to experts, to be successful in representing the physical characteristics and ultrasound profile of significant anatomical structures. This novel DIY product could be an effective alternative to teach procedures in the context of resource-restrained clinical simulation centers.

Exploring Interactions between Antibiotics Drugs and Amino Acids through Volumetric and Ultrasonic Properties at Different Temperatures

Exploring Interactions between Antibiotics Drugs and Amino Acids through Volumetric and Ultrasonic Properties at Different Temperatures

LATTICE DYNAMICAL STUDY OF THORIUM SULPHIDE

Thorium sulfide (ThS) is a chemical compound composed of thorium and sulfur atoms, with the chemical formula ThS. It belongs to the class of sulfides. To understand the dimensional stability and thermal behaviour of thorium sulphide (ThS), a lattice dynamical research issued to investigate its vibrational characteristics. We study the density of states (DOS) and phonon dispersion in the 50–60 GHz frequency region using computational techniques. Important information about the stability of the ThS crystal structure are given by the phonon dispersion curves, namely the presence of imaginary phonon frequencies that point to dynamical stability. We identify the major modes of vibration and their contributions to the thermodynamic properties of ThS through studying the phonon density of states.Van der Waals' three-body force shell model is used in this study to theoretically investigate the lattice dynamical behaviour of (ThS...). Elastic constants, pressure derivatives, dispersion relation curve, combined density of states, equation of state, and specific ultrasonic properties of the ThS are among the parameters for which calculated values are gave.The stability of the structure and vibrational properties of thorium sulphide are now better known by lattice dynamical study, which provides the way to its effective application in a range of technological uses, from nuclear reactors to the production of creative materials. Keywords: lattice, dynamics, thermal, vibrational

Ultrasonic properties and damage expression of frozen soil-rock mixture with various block conditions

Ultrasonic properties and damage expression of frozen soil-rock mixture with various block conditions

An ultrasound approach to characterize mixtures of vegetable oils with the same type of dominant chemical compositions

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.

The Effect of Freeze-thaw on Mechanical and Ultrasonic Properties of Hungarian Oolitic Stones

The freeze-thaw process is a weathering phenomenon that occurs in rocks and stones when water enters small cracks and pores within the stone. When the temperature drops below freezing, the water inside the rock expands as it freezes, exerting pressure on the rock from within. In this study the effect of freeze thaw on mechanical parameter uniaxial compression strength (UCS) and ultrasonic pulse velocity (UPV) of 47 oolitic samples were considered. At first, capillary absorption for cylindrical and prismatic oolitic samples were measured and then freeze-thaw experiment with 23 cycles were applied to the samples. UPV of samples before and after freeze-thaw was analysed by two ultrasonic devices including Geotron and Pundit. It was observed that freeze thaw decreases primary velocity (Vp) and secondary velocity (Vs) by around 20 and 7% respectively. However, average UCS of 1.6 MPa indicates strength decrease of samples, which represent negative effect of pore expansion due to freeze thaw on strength parameter of samples.

Finite element modeling of ultrasonic attenuation and dispersion in graded multilayer polymer composites

In this paper, finite element models of ultrasonic wave propagation in Cu–PMMA composites are established. The effects of second-phase particles, ultrasonic properties, and graded interfaces on the ultrasonic propagation behavior are investigated, and the contributions of particle-independent scattering, particle interactions, and matrix viscoelasticity to the ultrasonic attenuation are quantitatively evaluated. The results show that there is no obvious coupling between particle scattering and matrix viscoelasticity in Cu–PMMA composites, and the longitudinal wave speed has little effect with the variation of particle size, ultrasonic frequency, and graded interface, while the variation of the acoustic attenuation coefficient is related to the disorder of ultrasonic energy propagation direction. In the intra-layer uniform model, with the increase in Cu particle size and ultrasonic frequency, the scattering effect of Cu particles on the ultrasonic waves is enhanced, resulting in a significant increase in the acoustic attenuation coefficient. In the inter-layer graded multilayer model, there is a strong reverse energy propagation between the layers, causing the acoustic attenuation coefficient to increase significantly.

Statistical analysis of physico-mechanical parameters of sandstones occurring in orogenic settings

In northeastern Sicily (Italy), sandstone rock masses widely crop out as cover deposits over crystalline terrains belonging to the orogenic belt. Despite being part of the same geological formation, these sandstones are characterized by highly different features in terms of texture and physico-mechanical properties. This poses a scientific question on the possibility of tracing these rocks to a single statistical model, which could be representative of their main engineering geological properties. Therefore, it is worth investigating on the possible reasons of such differences, that should be searched either in the current geographical sandstone distribution or in the rock texture. For this study, sandstone samples were collected from different sites and were analyzed at both the hand and thin section scales. Three sandstone types were recognized, characterized by a different texture. Then, the laboratory characterization allowed estimating their main physico-mechanical and ultrasonic properties, such as porosity, density, mechanical strength, deformability, and ultrasonic velocities. The rock mechanical strength proved linked to the rock compactness and to the presence of lithic fragments, while pores and a pseudo-matrix between grains represent weakening features. Rock data were also statistically analyzed by grouping the specimens according to a geographical criterion, with respect to their sampling area, but no link was found between location and rock properties. Finally, with the aim of achieving mathematical laws that could be used to predict some rock properties from others, useful for practical purposes when dealing with such a high property variability, single and multiple regression analyses were carried out. Results show that the Uniaxial Compressive Strength, porosity, and P-wave velocity are the best predictors for a quick, indirect estimation of the main physico-mechanical parameters. The methodological approach developed for this research can be taken as reference to study other worldwide cases, involving rocks characterized by a wide range of physico-mechanical properties and covering large regional territories.

Temperature Dependent Behavior of Elastic and Ultrasonic Proprieties of Transition Metal Carbide Mo2C Superconductor

Abstract: Transition metal carbides exhibit peculiar chemical and physical properties, making them integral to industrial applications that demand performance under high temperatures In the case of the hexagonal transition metal carbide Mo2C superconductor, higher-order elastic constants were calculated to be temperature-dependent using an interactional potential model. Second-order elastic constants are used to determine other allied ultrasonic variables. Second-order coefficients are used to analyze the temperature variation of ultrasonic velocities along the z-direction of the superconductor. Furthermore, the temperature difference of Debye average velocity and thermal relaxation time are considered along the same direction. The temperature dependence of ultrasonic properties is explored in relation to thermal, elastic, and mechanical properties. Ultrasonic attenuation , resulting from phonon–phonon (p–p) interactions, is calculated at different temperatures .The study establishes that thermal conductivity is a core provider of the observed ultrasonic attenuation, particularly at higher temperatures. The mechanical and thermal properties of the Mo2C superconductor are superior at lower temperatures. Keywords:Transition metal carbide superconductor, Thermal conductivity, Ultrasonic properties, Elastic properties, Mechanical properties. PACS numbers: 43. 35. Cg; 62.20.Dc; 63.20.Kr.

Investigation of physical and metallographic properties of nickel matrix composite by ultrasonic method

Ultrasonic testing (UT) is one of the most widely used non-destructive testing techniques for the characterization and evaluation of materials. In this study, the material properties of AstCrM-BN-Cr-Ti-Ni composites produced by mechanical mixing and electroless nickel plating technique were evaluated using UT. Changes in ultrasonic wave velocity, Young's modulus, density, porosity and hardness are observed in the heat-treated material at different temperatures. Samples analyzed by Scanning Electron Microscopy (SEM) and X-Ray Diffractometry (XRD) exhibited changes in grain structure at different sintering temperatures. It has been observed that the change in grain size also affects mechanical and physical properties according to ultrasonic properties. In conclusion, the experimental results showed a linear relationship between the mean grain size and the UT parameters (ultrasonic longitudinal and transverse velocity, Young's modulus), physical (sintering temperature and density) and mechanical properties (hardness and porosity) of the material. Grain growth occurs with increasing sintering temperature, porosity content decreases, hardness, Young's modulus and ultrasonic wave velocity values also increase.