Ultrasonic Studies Research Articles

Improved Performance of Carbamazepine and Benzodiazepine by Oxygen Enrichment through Perfluorodecalin for Lennox-Gastaut Type of Seizures

Lennox-Gastaut syndrome is commonly characterized by a triad of features including multiple seizure types, intellectual disability or regression. The long-term prognosis for Lennox-Gastaut syndrome is generally poor due to uncontrolled seizures. Lennox-Gastaut syndrome type of seizures is epilepsy which is due to abnormal vibrations occurring in seizures. During the time of such abnormal vibrations, both the seizures and the lungs suffer a lack in oxygen content to a considerable extent. This results in prolonged vibrations and loses of nervous control. As a neuro-lung protective strategy, a novel attempt has been made to enrich both seizures and lungs with oxygen content through the support of perfluorodecalin (an excellent oxygen carrier) C10F18 along with an enhancement in the antiepileptic activity by the two chosen antiepileptic drugs carbamazepine and benzodiazepine. The ultraviolet-visible spectrophotometer, fluorescence spectrograph, ultrasonic laser diffraction and scanning electron microscope studies reveals the co-existence of fluorine and drug in the emulsion produced by the sonication of both perfluorodecalin and the drug together. The presence of adequate fluorine and carbon play a catalytic role in ensuring the oxygen content and the antiepileptic activity of drug components.

Density, viscosity and ultrasonic velocity study: Binary mixtures of 3-bromoanisole and methanol at different temperatures

The values of density, viscosity and ultrasonic velocity at three different temperatures (303.15, 313.15 and 323.15 K) of the prepared binary mixture solutions with different compositions of 3-bromoanisole (3-BA) and methanol (MeOH) are experimentally determined and presented. Moreover, the excess values of molar volume, viscosity and ultrasonic velocity have been determined. These determined excess properties are fitted to the Redlich-Kister equation. Deviations from the linearity are found in the experimentally measured parameters with variation in mixture composition and are interpreted in terms of molecular interaction. Moreover, thermodynamic properties are evaluated to understand the dynamic behavior of the system.

Study of continuous flow ultrasonication to improve total phenolic content and antioxidant activity in sorghum flour and its comparison with batch ultrasonication

Ultrasonic technology was applied to release the phenolics bound with starch and protein matrix in order to enhance total phenolic content (TPC) and antioxidant activity (AA) of the sorghum flour. Both the continuous flow and batch ultrasonication were implied with independent variables such as flour to water ratio (FWR), ultrasonication intensity (UI), and ultrasonication time (UT) with an additional variable as flow rate (FR) in continuous flow ultrasonication. All the process variables showed a significant effect on the corresponding ultrasonication process. The optimal conditions for the continuous flow ultrasonication were a FWR of 10% w/v, an UI of 20 W/cm2, an UT of 130 s, and 15 ml/s FR which produced a maximum values of 70.9 mg GAE/100 g dry matter (d.m.) for TPC and 143.9 µmol TE/100 g d.m. for AA. Regarding the batch ultrasonication, the maximum values were 65.6 mg GAE/100 g d.m. and 141.0 µmol TE/100 g d.m. for TPC and AA, respectively at optimum conditions of 10% w/v FWR, 30 W/cm2 UI, and 200 s UT. When comparing with the batch ultrasonication, the continuous flow process saved 35% time and 33% of energy consumption to obtain comparatively higher TPC and AA of the sorghum flour. Ultrasonication improved free phenolic acid content by releasing bound phenolics in the sorghum flour. Impact of various process parameters on specific energy was analyzed during both the processes, and influence of energy on TPC and AA of the sorghum flour was also observed for the batch and continuous flow ultrasonication.

Ultrasonic evidence of temperatures characteristic of relaxors in PbFe2/3W1/3O3–PbTiO3 solid solutions near the morphotropic phase boundary

We present an ultrasonic study of relaxor-based solid solution (1−x) PbFe2/3W1/3O3–x PbTiO3 (0.25 ≤ x ≤ 0.35) located within the morphotropic phase boundary (MPB). The longitudinal ultrasonic wave velocity and attenuation have been measured by the ultrasonic pulse-echo technique at a frequency of 10 MHz in a wide temperature range from 200 to 800 K. Attenuation peaks have been observed at characteristic temperatures, namely, at Burns temperature TB and the additional distinctive temperature T*. To explain the experimental results, we consider a modified polar nanoregions (PNRs) model taking into account fluctuation corrections of ultrasonic wave velocity and attenuation in the vicinity of both TB and T*. The obtained results confirm the dynamic nature of MPB effects which determine the physical properties of relaxor-based solid solutions.

The Role of Titanium Dioxide on the Hydration of Portland Cement: A Combined NMR and Ultrasonic Study.

Titanium dioxide (TiO2) is an excellent photocatalytic material that imparts biocidal, self-cleaning and smog-abating functionalities when added to cement-based materials. The presence of TiO2 influences the hydration process of cement and the development of its internal structure. In this article, the hydration process and development of a pore network of cement pastes containing different ratios of TiO2 were studied using two noninvasive techniques (ultrasonic and NMR). Ultrasonic results show that the addition of TiO2 enhances the mechanical properties of cement paste during early-age hydration, while an opposite behavior is observed at later hydration stages. Calorimetry and NMR spin–lattice relaxation time T1 results indicated an enhancement of the early hydration reaction. Two pore size distributions were identified to evolve separately from each other during hydration: small gel pores exhibiting short T1 values and large capillary pores with long T1 values. During early hydration times, TiO2 is shown to accelerate the formation of cement gel and reduce capillary porosity. At late hydration times, TiO2 appears to hamper hydration, presumably by hindering the transfer of water molecules to access unhydrated cement grains. The percolation thresholds were calculated from both NMR and ultrasonic data with a good agreement between both results.

Ultrasonic vibration-assisted thread cutting technology

The technology of ultrasonic method of tapping is presented in this paper. With the help of a special ultrasonic device comparative studies of the influence of ultrasound on the process of cutting internal threads were conducted. The research into the influence of the tap size on the cutting torque was also conducted. Presented dependencies show that in the case of ultrasonic processing there is a decrease in the values of the cutting torque in the whole range of investigated velocities. The additional wear-resistant coating on the tap also reduces the cutting torque, which ultimately leads to an increase in the tap resistance period.

Volumetric and ultrasonic study of polyethylene glycols in aqueous solutions of niacin at different temperatures

Significant information regarding the molecular interactions in the ternary solution consisting of Vitamin B3 (Niacin), water and polyethylene glycols (PEG 200/PEG 600) are attained from the calculated volumetric and acoustic parameters. Initially, the density (ρ) and speed of sound (c) for polyethylene glycols (0.1 to 0.5) mol∙kg−1 in aqueous niacin (0.01, 0.02, and 0.03) mol∙kg−1 were measured under 0.1 MPa pressure as a function of temperature at (293.15–308.15) K. Utilizing the experimental density values, the apparent Molar Volume (Vϕ), Partial Molar Volume (Vϕ0) and Partial Molar Volume of transfer (ΔVϕ0) are calculated and the apparent Molar Isentropic compression (Kϕ,S), Partial Molar Isentropic compression (Kϕ,S0) and Partial Molar Isentropic compression of transfer (ΔKϕ0) are estimated using the speed of sound. The empirical constants a, b, and c along with the pair and triplet coefficients (VAB,VABB,KAB,KABB) are calculated.

A study on Al 2219 alloy precipitate growth rates by non-linear ultrasonic technique

A non-linear ultrasonic study has been carried out to characterise the variation in precipitation phase. An age-hardenable aluminium alloy (2219) has been taken as a model alloy for the present investigation. It is shown that there is a strong correlation between the change in the non-linear coefficient and the change in the precipitated phase. The observed variations in the non-linear ultrasonic parameter have been explained by modifying an existing dislocation-coherent precipitate interaction model for the generation of harmonics in order to account for a weaker dislocation-semicoherent precipitate interaction. In general, the model proposed can be applicable to all precipitation-hardenable alloy systems undergoing coherent to incoherent precipitate phase transition.

Ultrasonic Regeneration Studies on Activated Carbon Loaded with Isopropyl Alcohol

Ultrasonic regeneration of activated carbon loaded with isopropyl alcohol (IPA) was studied. IPA adsorption was performed batchwise at varying solution pH. Adsorption was optimal at solution pH 7, which was closest to the point of zero charge of the activated carbon (6.7). Ultrasonic regeneration was performed on IPA-loaded activated carbon with three factors being tested: ultrasonic intensity, solution temperature and ethanol addition. Regeneration efficiency increased with ultrasonic intensity up to 32.4 W/cm2. A higher intensity led to a higher desorption but damaged the activated carbon, shown by a decrease in the particle size of activated carbon. The regeneration efficiency increased with solution temperature primarily because desorption is endothermic and because the surface tension and viscosity of a solution are reduced with increasing temperature, promoting cavitation bubble production. Ethanol addition increased regeneration efficiency up to 10%, as ethanol reduces tensile stress, facilitating cavitation bubble generation. At 15% and above, regeneration decreases, possibly due to coalescence of bubbles into larger, more stable bubbles. Under optimal parameters, the regeneration efficiency was 83%, which dropped to 64% after four regeneration cycles.

Thermodynamic, Ultrasonic, and Transport Study of Binary Mixtures Containing 2-(2-Methoxyethoxy)ethanol and Alcohols at (293.15–323.15) K

Binary mixtures of 2-(2-methoxyethoxy)ethanol and alcohols were characterized in terms of the existence of intermolecular interactions at different temperatures (293.15, 303.15, 313.15, and 323.15) K and at pressure p = 0.1 MPa. The alcohols were methanol, ethanol, propan-1-ol, propan-2-ol, butan-1-ol, and butan-2-ol. The study was based on the measurements of densities, speeds of sound, and refractive indices over the entire range of mixture compositions. The obtained data were used to calculate various thermodynamics/deviation properties: excess molar volume, isentropic compressibility, deviation in isentropic compressibility, and deviation in refractive indices. Excess/deviation properties were fitted to the Redlich–Kister equation to estimate the coefficients. The standard deviation of the fit was calculated between the predicted and the experimental quantities to ensure the accuracy of the experimental data.

Use of Higher-Harmonic and Intermodulation Generation of Ultrasonic Waves to Detecting Cracks due to Steel Corrosion in Reinforced Cement Mortar

The aim of this work was to provide further confirmation of the possible use of non-linear ultrasonic techniques for detecting the cracking due to corrosion of steel reinforcements in concrete. To this end accelerated steel corrosion tests have been conducted on model reinforced cement mortar specimens, while monitoring the appearance and width evolution of visible surface cracks, and performing non-linear ultrasonic measurements based on the phenomena of harmonic distortion and intermodulation. A new parameter, based on the difference between the amplitude of the fundamental frequency and the sum of the amplitudes of all the first-order and second-order intermodulation products, has been proposed in this work. The results confirm that the appearance of visible surface micro-cracks are preceded and accompanied by the observation of strong non-linear features in the received signal. Furthermore, the new parameter proposed in this work is as efficient as the relative non-linearity parameters, classically used in harmonic distortion non-linear ultrasonic studies, for detecting the non-linear features associated with the critical events of the cracking of cement mortar due to embedded steel corrosion. A hypothesis has been developed considering the possible effect of the filling of the void space by liquid containing rust products after the formation of new cracks or the enlargement of its width. This filling process, which might be particularly enhanced by net convective transport of liquid, would explain the evolution of the values of all the parameters used for putting in evidence the non-linear elastic features after the critical events of the cracking process.

Ultrasonic Study of Anionic Surfactants in Binary Liquid Mixtures

Ultrasonic Study of Anionic Surfactants in Binary Liquid Mixtures

Ellipsometric and ultrasonic studies of nano titanium dioxide specimens doped with Erbium

Nano Er-doped TiO2 thin films prepared by sol-gel technique at different doping concentrations (5%, 7%, 9%, and 11%). The prepared thin films were studied through ultrasonic and ellipsometric measurements. Mechanical properties are known from the ultrasonic method that investigated the effect of the Er-doped amount on the cross-link density, bond strength, elastic properties, and stress-strain relation between atoms of TiO2 thin films. Ellipsometric measurements studied the variation of optical transmittance, energy band gap, refractive index, Urbach energy roughness, and porosity with changing Er-doped amount. Finally, contact angle measurements are done to ensure the self-cleaning property of the prepared thin films. Results deduced that Er-doped enhanced greatly TiO2 thin films, to be used in many industrial applications as self-cleaning glass fabrication.

Estimation of Effectiveness of Lymphoma Treatment with Damage of Peripheral Lymph Nodes Using Ultrasonic Study with Contrast Enhancement

Purpose : To evaluate the possibilities of ultrasound examination with contrast enhancement (CEUS) in assessing the effectiveness of treatment of patients with specific lesions of peripheral lymph nodes with lymphoproliferative lesions. Material and methods : To assess the capabilities of CEUS in assessing the effectiveness of treatment, a study was carried out for 15 patients with lesions of peripheral lymph nodes in lymphoma in dynamics before the treatment and after 2 or 3 courses of chemotherapy using a contrast agent SonoVue® in a volume of 4.8 ml. The results of the study were analyzed and compared with traditional ultrasound techniques. Ultrasound examination was performed using Siemens Acuson S2000 and Philips Affiniti 70 devices with high-frequency linear transducers from 5 to 12 MHz. Results : CEUS revealed a significant increase in the TTP parameter from 27 ± 12 s to 36 ± 13 s ( p = 0.0496) and a significant decrease in the PI parameter from 9 ± 5 dB to 4 ± 3dB ( p = 0.00047). Conclusions : CEUS at any stage of the treatment seems to be promising since it allows diagnosing of structural changes in the affected lymph nodes even after one cycle of chemotherapy.

The effect of ultrasonication on enzymatic hydrolysis of chitin to N-acetyl glucosamine via sequential and simultaneous strategies

In this study, sequential and simultaneous strategies of ultrasonication (ultrasonic bath) were investigated to enhance enzymatic production of N-acetyl glucosamine (GlcNAc) from chitin powder. For the sequential strategy, the ultrasonic caused chitin powder to a visible fleecy structure, and Scanning electron microscopy (SEM) showed the surface of the treated chitin had a fiber-like structure with a diameter of 50 − 200 nm. Moreover, Fourier transform infrared spectroscopy (FTIR), Element analysis (EA), and X-ray diffraction (XRD) revealed that the crystallinity of the chitin decreased with little deacetylation. The simultaneous strategy is a one-pot treatment and enzymatic hydrolysis of chitin. The concentration of GlcNAc was 2.65 g/L for the strategy, which was 1.18- and 5.0-fold higher than the sequential strategy (2.25 g/L) and untreated chitin (0.53 g/L), respectively. In conclusion, this approach provided an efficient and environmentally friendly method for reducing the crystallinity of chitin and enhancing its enzymatic hydrolysis.

Ultrasound Study of the Quality of Consolidation Grouting Works for Retaining Rocks in Underground Structures

The effectiveness of consolidation grouting for retaining surrounding rocks of the turbine hall at the Rogun hydro power plant (HPP) on the Vakhsh River in southern Tajikistan is evaluated. The ultrasonic method is used to examine samples, informing the choice of a test site in the aleurolite zone, as well as a drilled grout and test hole scheme. The results of processing and analysis of the ultrasonic study results are presented.

Splenic morphometric characteristics in infectious mononucleosis (ultrasonic study)

The spleen is a secondary immune and the largest organ of the reticuloendothelial system, actively involved during infectious mononucleosis. Clinically, assessing a degree of organ involvement in the pathological process seems unlikely. As a rule, only palpation and percussion are used to determine the size of the spleen, which represents a late and subjective sign of potential splenomegaly. Ultrasound examination provides ample opportunities to estimate the spleen size during infectious mononucleosis. Our study was aimed at identifying morphometric and Doppler ultrasound changes in the spleen in patients with infectious mononucleosis. Materials and methods. There were enrolled 24 patients with infectious mononucleosis to be compared with 30 healthy medical institute students in control group. All participants underwent splenic ultrasound examination. Spleen echotexture and contour clarity together with measuring linear dimensions: length, width, and thickness were analyzed. Splenic artery and vein velocity parameters were measured at the gates of the spleen. Elastographic window for fibroelastometry was positioned within the window for standard grayscale examination. Measurements were performed at 5 or more points of the spleen parenchyma at least 4—5 mm away from the capsular zone and the zone of large vessels. Based on the morphometric measurements obtained, the mass, spleen mass coefficient (SMC), as well as the spleen mass/body height ratio and spleen mass/body surface area ratio were calculated. Results. We found that patients with infectious mononucleosis had the length, thickness and weight of the spleen significantly greater than those observed in control group. However, the mass of the spleen varies widely and justified to calculate the CMS as an objective criterion to assess the size of the spleen. It was revealed that infectious mononucleosis may proceed in one of the three variants of the splenic response: decreased size, CMR 1.5; normal size, CMR ranged from 1.5 to 4; splenomegaly, CMR 4. Splenomegaly is associated with increased organ stiffness, peak blood flow velocity and pressure in v. lienalis, as well as periportal lymphadenopathy. Identified changes are characteristics of young patients. Conclusion. Ultrasound examination of the spleen is of high diagnostic value for patients with infectious mononucleosis allowing highly accurate assessment state of the immune organs in the acute disease period. At the preclinical stage, gradation of splenomegaly is possible depending on its intensity, assessed hemodynamics and organ stiffness.

Insights into non-ideal behaviour of benzyl alcohol with (C2-C4) carboxylic acids through volumetric, ultrasonic and ATR-FTIR spectroscopic studies

ABSTRACT In the present work, experimental density (ρ) and speed of sound (u) data for the binary mixtures of benzyl alcohol with acetic acid, propionic acid, and n-butyric acid have been reported over the complete range of mole fraction at 298.15 K ≤ T ≤ 313.15 K. Excess volumes (VE ), excess isentropic compressibilities (κs E ), excess partial molar volumes (), and excess partial molar volumes at infinite dilution () have been computed from the experimental data. The excess thermodynamic properties are found to be negative over the entire range of composition at the investigated temperatures. The temperature dependence of the excess thermodynamic properties has been investigated. All the excess functions are correlated with the Redlich-Kister equation. Further, attenuated total reflection Fourier transform infrared (ATR-FTIR) spectra for the studied binary solutions have been recorded at the equimolar composition to evaluate the extent of cross-association between component molecules through intermolecular hydrogen bonding.

Ultrasonic rock microcracking characterization and classification using Hilbert–Huang transform

This study aims to set up a non-destructive method to control the quality of aggregates using ultrasonic wave acquisition and processing. Two applications are presented proving the applicability of the proposed methodology. The first is the characterization and classification of four limestone rocks from cement quarries in the northern part of Tunisia selected from different geological ages (Lower Jurassic, Upper Cretaceous, and Lower Eocene). The second application deals with assessing rock crushing-induced microcracking evolution in quarried rock from the first initial source rock mass to the final aggregate. Five stages were considered: before the blast (bench front), after the blast round (muck pile), after the primary crusher, after the secondary crusher, and after the tertiary crusher. A physico-chemical and ultrasonic characterization was performed on aggregates and core samples in order to identify their characteristics namely the crack porosity and P-wave velocity. A cluster statistical analysis was then adopted to classify the investigated samples into several groups where crack porosity is the most relevant factor in classifying their quality. In addition to measuring ultrasonic parameters such as the spatial attenuation and P-wave velocity, the ultrasonic study looks at the spectrum of the received signal (non-stationary and nonlinear signal) by measuring the instantaneous energy density with the Hilbert–Huang transform. Beyond the fact that the high negative correlation between the P-wave velocity and the instantaneous energy was identified, the methodology developed allowed to prove that the latter is a relevant factor for the classification of limestone rocks.

Ultrasonic and Thermophysical Studies of Ethylene Glycol Nanofluids Containing Titania Nanoparticles and Their Heat Transfer Enhancements

In the present investigation, TiO2 nanostructures were synthesised via a simple sol-gel technique and characterised with X-ray diffraction (XRD), scanning electron microscopy with energy-dispersive X-ray analysis (SEM-EDX), high-resolution transmission electron microscopy (HR-TEM) and ultraviolet-visible (UV-vis) spectroscopy. The temperature and concentration dependence of thermal conductivity enhancement (TCE) and ultrasonic velocity have been explored in ethylene glycol-based TiO2 nanofluids. The obtained results showed 24% enhancement in thermal conductivity at higher temperature (80°C) of the base fluid ethylene glycol by adding 1.0 wt% of TiO2 nanoparticles. The behaviour of TCE and ultrasonic velocity with temperature in prepared nanofluids has been explained with the help of existing phenomena. The increase in ultrasonic velocity in ethylene glycol with TiO2 nanoparticles shows that a strong cohesive interaction force arises among the nanoparticles and base fluid. These results divulge that TiO2 nanoparticles can be considered for applications in next-generation heat transfer in nanofluids.