Influence Of Ultrasonic Waves Research Articles

Ultrasonic-assisted preparation of SBS modified asphalt: Cavitation bubble numerical simulation and rheological properties

SBS (styrene–butadiene–styrene block copolymer) is currently the most widely used asphalt modifier, and SBS modified asphalt is usually prepared by high-speed shearing. This paper combines the cavitation effect of ultrasonic to assist in the preparation of SBS modified asphalt, and conducts numerical simulation and rheological properties research on the cavitation bubbles in the molten SBS modified asphalt fluid. The cavitation bubbles in the modified asphalt fluid will expand and contract as the pressure changes inside and outside the bubbles. When the cavitation bubble is compressed to the minimum and the pressure inside the bubble reaches 1.94 × 105Pa, the direction of the velocity vector near the cavitation bubble will change with the expansion and compression of the bubble. The expansion–contraction process of a single cavitation bubble can release 6.41 × 10-7J of energy, thus breaking the long bonds in asphalt and generating a large number of free radicals react with the unsaturated C = C bonds in the SBS molecules. According to the preparation process of modified asphalt, the influence of ultrasonic wave on rheological property of modified asphalt was studied through experiments. The results show that ultrasonic treatment can enhance the elasticity of asphalt and improve the temperature sensitivity of asphalt. With the increase of ultrasonic treatment time, the anti-rutting deformation ability of SBS modified asphalt is greatly improved. At the same temperature, the recovery rate of asphalt also increases with the increase of ultrasonic treatment time, and the non-recoverable compliance (Jnr) decreases Combined with the numerical simulation of cavitation bubbles, the ultrasonic process is added to asphalt production, which is of great significance for the green production of modified asphalt and the improvement of the rheological properties of modified asphalt.

Experimental study on dynamic wetting behavior of liquid droplets on the aluminum surfaces excited by ultrasonic waves

In this paper, an anti-frosting strategy utilizing ultrasonic excitation to drive droplets away from cold surfaces was proposed. Based on this strategy, experimental studies were conducted to investigate the dynamic wetting behavior of droplets on aluminum surfaces under ultrasonic excitation. Specifically, the vibration characteristics of the plate and the properties of the droplets were revealed under the influence of ultrasonic waves. The results indicate that the droplet will undergo three stages of spreading-movement-contraction under ultrasonic excitation and the maximum contact angle hysteresis and maximum diameter spreading rate exhibit a positive correlation with droplet volume and ultrasonic power. It is also found that ultrasonic excitation can significantly reduce the droplet contact angle, which can be reduced by up to 70°. The contact angle hysteresis, diameter spreading rate and movement velocity show almost the same trend with time under ultrasonic action, that is, increasing first and then decreasing. Notably, the contact angle hysteresis and the diameter spreading rate reached a peak later than the movement velocity, which is attributed to the droplet's deformation relies on the full propagation of the ultrasonic vibration inside the droplet, resulting in hysteresis. Finally, it is found that the droplet-wetting state is permanently changed under ultrasonic action and the final contact angle is greatly reduced compared to the initial value even after stopping ultrasonic excitation.

Increasing oil absorption in bearings as a result of ultrasonic exposure to ultrafine particles

The article proposes an approach that ensures an increase in oil absorption by bearings as a result of ultrasonic exposure to ultrafine particles. The approach is based on the method of thermodynamics and kinetics of the formation of inorganic ultrafine particles in liquid-phase processes. The work shows that one of the promising ways to improve the antifriction characteristics of bearing materials is the impregnation of porous hardened materials with oils with the addition of special solid carbon additives. The goal of the work is to develop an antifriction self-lubricating powder material that meets modern requirements for bearing units. The cavitation method is considered taking into account the impact action of liquid microjets. In this case, the ratio of the sizes of the cavitation bubble and the solid particle is taken into account. An increase in the effectiveness of the influence of ultrasonic waves on the oil absorption of the bearing material has been shown.

A novel synthesis for the preparation of LiNbO3 powder with high piezoelectric catalytic performance

The traditional method for producing lithium niobate (LiNbO3) powder is based primarily on a solid-state reaction, which has a high energy consumption and low efficiency, requiring long periods of insulation at a high temperature of 1000–1300 °C. In this work, high-purity and high-crystallinity LiNbO3 powder was prepared by using niobium pentoxide (Nb2O5) and lithium fluoride (LiF) at 800 °C for 0.5 h. Interestingly, the prepared LiNbO3 powder demonstrated exceptional piezoelectric catalytic degradation performance and reusability. Under the influence of ultrasonic waves, the LiNbO3 powder achieved complete degradation of Rhodamine B (RhB) within a remarkably short duration of 20 min, with a reaction rate constant of 0.2702 min−1, which was 7.9 times larger than that of commercial LiNbO3 (0.03416 min−1). Furthermore, even after undergoing six degradation cycles, the powder maintained its high degradation efficiency. Active substance trapping and detection experiments revealed the presence of hydroxyl radicals (•OH) and superoxide radicals (•O2−) with potent oxidizing capabilities during the piezoelectric catalysis process, affirming their pivotal roles in the degradation of RhB. The energy-saving and efficient method employed in acquiring LiNbO3 would provide an exciting pathway towards the development of efficient catalysts for organic wastewater treatment, fueled by clean energy sources.

Shape and diffusion instabilities of two non-spherical gas bubbles under ultrasonic conditions

Ultrasonic cavitation involves dynamic oscillation processes induced by small bubbles in a liquid under the influence of ultrasonic waves. This study focuses on the investigation of shape and diffusion instabilities of two bubbles formed during cavitation. The derived equations for two non-spherical gas bubbles, based on perturbation theory and the Bernoulli equation, enable the analysis of their shape instability. Numerical simulations, utilizing the modified Keller–Miksis equation, are performed to examine the shape and diffusion instabilities. Three types of shape instabilities, namely, Rayleigh–Taylor, Rebound, and parametric instabilities, are observed. The results highlight the influence of initial radius, distance, and perturbation parameter on the shape and diffusion instabilities, as evidenced by the R 0–P a phase diagram and the variation pattern of the equilibrium curve. This research contributes to the understanding of multiple bubble instability characteristics, which has important theoretical implications for future research in the field. Specifically, it underscores the significance of initial bubble parameters, driving pressure, and relative gas concentration in determining the shape and diffusive equilibrium instabilities of non-spherical bubbles.

Effects of ultrasound on the removal of emulsion plugging in oil reservoirs

The generation of water-in-crude oil emulsions in a reservoir can cause formation damage due to droplet trapping at pore spaces. The removal of the damage is anticipated to be inexpensive and eco-friendly when done with ultrasound as opposed to chemical demulsifiers. The influence of ultrasonic power and frequencies on the removal process, however, is not well understood. Additionally, the process's underlying mechanism is largely speculated. In this study, the effect of ultrasound on the removal of emulsion plugging in oil reservoirs was investigated using a glass micromodel. Emulsion blockage during oil production was replicated in the micromodel and subjected to different ultrasonic frequencies (20 and 40 kHz) and powers (100–1000 watt). The experiments demonstrate that when ultrasonic power and frequency increase from 100 to 1000 watt and 20–40 kHz, respectively, demulsification effectiveness decreases. Ultrasound at low frequency (20 kHz) and power (100 watt) proved to be the most efficient condition to dislodge trapped emulsions in the micromodel pores, facilitate droplet coalescence and increase fluid recovery. The percentage of recovered emulsions increased to 58 % when the micromodel was exposed to ultrasound (20 kHz, 100 watt), as opposed to 53.3 % in the case without ultrasound. This study provides insights into the microscopic behavior of emulsions under the influence of ultrasonic waves, allowing petroleum engineers to optimize ultrasound demulsification process.

Chemical Viscosity Reduction of Heavy Oil by Multi-Frequency Ultrasonic Waves with the Main Harmonics of 20–60 kHz

Ultrasound technologies are well-known for their ability to intensify the heat and mass transfer processes. Hence, ultrasonic treatment processes are widely applied for the separation of oil–water emulsions, optimization of oil pumping processes, cleaning the bottomhole zone, etc. However, the main phenomenon under the positive influence of ultrasonic waves on such processes is the cavitation bubbles implosion on the water–oil boundary. It is well-known that ultrasound energy contributes to the reversible viscosity reduction in heavy oil systems. However, it is possible to exhibit chemical destruction of the weakest carbon–heteroatom bonds in the structure of the asphaltenes. This study investigates the influences of controllable ultrasound waves with frequency ranges of 20–60 kHz under the exposure time of 60 s on the rheology of a heavy crude oil sample produced from the Ashalcha reservoir (Tatarstan Republic, Russia). The specific feature of this study is the application of multi-frequency ultrasonic exposure with a wide spectrum of side harmonics with the frequency up to 400 kHz. The results of the Saturates, Aromatics, Resins and Asphaltenes (SARA) analysis method support the chemical consequences of ultrasonication of crude oil. The content of resins under the irradiation of ultrasound waves altered from 32.5 wt.% to 29.4 wt.%, while the number of aromatics hydrocarbons raised from 24.3 wt.% to 34.1 wt.%. The Gas Chromatography—Mass Spectroscopy (GC-MS) analytical analysis method was applied to qualitatively compare the composition of saturated and aromatics fractions between the initial and upgraded heavy crude oil in order to show the chemical destruction of asphaltene bonds after the ultrasonic treatment. It was demonstrated that ultrasound waves allowed chemical conversion of asphaltene fragments that led to irreversible viscosity reduction. The viscosity of the heavy oil sample under the favorable ultrasonic irradiation conditions reduced from 661.2 mPa·s to 178.8 mPa·s. This advantage can be used to develop enhanced oil recovery methods and partial upgrading processes in downstream conditions.

Effect of ultrasonic treatment during stir casting on mechanical properties of AA6063-SiC composites

In this work AA6063-Silicon carbide composites were fabricated using conventional stir casting. Agglomeration of reinforcement particles which is a serious drawback in conventional stir casting was attempted to be reduced by applying ultrasonic waves to the composite melt after mechanical stirring. The composites were fabricated with different weight percentages (2,4,6 and 8%) of SiC particles having 10μm average particle size. The mechanical properties of the composites were evaluated for both the cases and were compared to study the influence of ultrasonic waves. It was found that the mechanical properties of the composite increased with increase in the weight percentage of the reinforcement up to 4 wt% SiC and reduced beyond that. The 4 wt% SiC stir cast composite subjected to ultrasonic waves showed 51.17%, 67.52% and 38.31% increase in ultimate tensile strength, yield strength and hardness respectively when compared to the base alloy.

The influence of ultrasonic waves on the characteristics of the radiation detector

The paper presents the results of a study of the field dependences of charge losses, silicon diffusion detectors that allow identifying single atoms and their clusters acting as charge carrier capture centers. In electric fields E > 1470 V/cm, there is an effective decrease in the capture processes, which manifests itself in the form of straightening of the field dependences of charge losses and in the narrowing of spectral lines. Effects - an ultrasonic field with an intensity of I * = 0.4 W / cm2 and a frequency of f = 15 MHz, on samples for a time t £ 45 minutes, leads to an increase in the amplitude of the signal. It is established that ultrasonic exposure leads to a decrease in charge loss, drift time and an improvement in the energy resolution of detectors. It should also be noted that fluctuations of the impurity relief in the Si-p-type volume are smoothed out after low-power ultrasonic waves pass through it for a long time, as evidenced by a significant decrease in the effective size of local defect clusters.

Influence of Ultrasonic Waves on Current-Voltage Characteristics and Polarization Effects of Si-N-P Radiation Receivers

The currents of n-p junctions and polarization effects caused by the capture processes of diffusion Si-receivers (detectors) of radiation exposed by ultrasound have been analyzed in this work. It was found that there are local concentrations of impurity atoms with an effective size l>6μm30μm in Si-n-p radiation receivers. They determine the behavior of the signal amplitude in different intervals of electric and temperature fields. It was found that at Е>1500V/cm and T>168K, the efficiency of collecting nonequilibrium charge carriers significantly increases and doublets of spectral α-lines and “humps” disappear at the temperature dependences of the signal amplitude. The main physical processes and mechanisms that determine the appearance of the phenomenon of "polarization" of Si-n-p-detectors were investigated. This phenomenon is caused by the existence of local gold atoms, which arise in the process of manufacturing technology of Si-n-p-receivers and act as effective trapping centers.

Influence of ultrasonic waves and conventional extraction methods on phenolic compound yield and phytochemical composition from Punica granatum L. peel

Abstract The objective of this work is to extract phenolic compounds from Punica granatum L. peel and to optimize the process variables. In this study, extraction was carried out using soxhlet, solvent and ultrasound-assisted extraction. Soxhlet extraction of phenolic compounds were reported as 87.31 mg GAE/g dW TPC, 70.30 mg RUE/g dW TFC and 98.68 mg CE/g dW TAC. Solvent extraction found 56.99 mg GAE/g dW, 42.93 mg RUE/g dW and 64.13 mg CE/g dW, while for ultrasonic-assisted extraction it was 77.23 mg GAE/g dW, 62.55 mg RUE/g dW and 91.40 mg CE/g dW of total phenolic content, total flavonoid content and total amount of anthocyanin content, respectively. The presence of phytochemicals was identified using GC-MS and it was found that the extracts contained high amount of trans-13-Octadecenoic acid which is a cancer preventive compound. Scanning electron microscope analysis was used to study the effect of ultrasound on the surface of the sample and understand the morphological changes.

Influence of ultrasonic waves on the gas-solid flow and the solids dispersion in a CFB riser: Numerical and experimental study

There are different ways to enhance the solids dispersion in the CFB risers, and the use of acoustic waves for this purpose is under-explored. In this context, a CFB-based design of experiments was proposed to investigate the influence of lower ultrasonic frequency and high intensity on the solids dispersion in a lab-scale CFB riser using Geldart B particles fluidized by ambient air at 5.7 m/s, with a solid mass flux of 1.60 kg/m2∙s. Maps of solids dispersion were developed in a range of sound frequencies from 20 kHz to 100 kHz and input power from 10 W to 50 W. The results indicated that ultrasounds enhanced solids distribution and the best dispersion was reached with 20 kHz and input power between 10 W and 50 W. It contributes to reducing cluster formation in the bottom region of the CFB riser and avoids the development of the core-annulus profile.

Solvent treatment on cloud point for dewaxing in crude oil industries

Dewaxing condition of all type of crude oil controlled by the cloud point temperature; the temperature where dissolved solids are no longer completely soluble, precipitating as a second phase giving the fluid a gloomy appearance. Ultrasound techniques was applied in Indian crude oil to confirm an optimum blended chemical which changes the thermo dynamical equilibrium with a suitable operating environment capable to decrease the cloud point temperature to improve the quality of crude oil analysis. Experiments were conducted on three solvent to crude oil ratios (10: 1, 15: 1 and 20: 1) for temperature range of 10°C to 50°C, with ultrasonically determined blended chemicals for appearance of bright spots on a black background for better separation. The dewaxing process was compared with two different diluents in a common extractant in terms of the efficiency of extraction and microscopic observation for wax appearance in crude oil. The results of dewaxing compared in terms of the efficiency of extraction and microscopic image visualization on crude oil. The data recorded with diluents of low carbon chain was found more suitable as compared to immediate higher carbon chain and discussed in terms of different influencing factors like oil solvent ratio, effect of temperature, settling time and influence of ultrasonic wave.

Contemporary directions of application of low power ultrasounds in anticancer therapy

In the recent years, research has been conducted on the role of ultrasounds (US) in anticancer therapy. Although the mechanisms of impact on cancer cells have not yet been fully understood, it is known that the best results are obtained using low power ultrasound. Currently applying ultrasounds to organisms is considered in three areas of influence: thermal (thermic effect), cavitation (cavitation effect), other than thermal and cavitation ones (non-thermal, non-cavitation effect). Under the influence of ultrasonic wave with low power, the absorption of drugs is increased as well as of anti-angiogenic activity. Sonodynamic therapy is aimed at destroying dividing cancer cells through the formation of free radicals in the cavitation mechanism and in the presence of sonosensitizers. At the same time under the influence of US, local hyperthermia is generated. In vivo studies showed a synergistic increase in cytotoxicity due to the effects of ultrasonic hyperthermia and adriamycin. The thermal effect and inertial cavitation are described as two factors induced by US, which may lead to damage to the vascular network within the neoplastic lesion. A proportional increase in tumor echogenicity to the frequency range of the applied ultrasound wave has been demonstrated. The strategy of combining US with photosensitizers, chemotherapeutics or contrast agents is gaining more and more recognition. Obtained results from inter developed studies on antineoplastic sonodynamic therapy indicate that it may become a new additional cancer treatment strategy.

Experimental investigation of the ultrasonic wave effects on the viscosity and thermal behaviour of an asphaltenic crude oil

In this study, the influence of ultrasonic waves on the viscosity and thermal behaviour of a crude oil with high asphaltene content at different irradiation times and powers/frequencies was investigated. It was found that the ultrasonic radiation significantly reduced the oil viscosity before the oil cooled down. The viscosity was then remeasured after the irradiated oil cooled down to the ambient temperature to evaluate the reversibility in viscosity at various time intervals. For each ultrasonic frequency, an optimum irradiation time was found at which the cooled-down irradiated oil reached a minimum viscosity. For the ultrasonic radiation with a frequency of 46 kHz and an output power of 50 W, it was found that the permanent viscosity loss of the cooled-down oil irradiated for an optimum time of 8 min was 10 %. The effects of ultrasonic irradiation on thermal behaviour of the oil were analysed using thermogravimetric and differential thermal (TGA/DTA) methods to evaluate the relation between changes in viscosity and thermal properties of the oil. It was found that the weight loss of the irradiated-oil was more than that of the non-irradiated oil at the end of both the pyrolysis and oxidation stages.

Study of the Influence of Ultrasonic Waves on Electro-physical Characteristics of Radiation Receivers

Study of the Influence of Ultrasonic Waves on Electro-physical Characteristics of Radiation Receivers

Sonochemical versus reverse-precipitation synthesis of CuxO/Fe2O3/MoC nano-hybrid: removal of reactive dyes and evaluation of smartphone for colorimetric detection of organic dyes in water media.

In the present work, an ultrasound-assisted reverse-precipitation method was applied as a new approach for the synthesis of CuxO/Fe2O3/MoC. In the sonication method, a bath type sonicator as a simple, cost-effective, and low intensity sonicator was used. To determine the influence of ultrasonic waves on the morphology and application of nano-hybrid as nano-sorbent, it was also synthesized using the reverse precipitation method. The products were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), Fourier transform infrared (FTIR), transmission electron microscopy (TEM), Zeta-potential measurement, and vibrating sample magnetometer (VSM) techniques. The XRD analysis confirmed that the sono-synthesized sample has higher crystallinity than the conventional one and CuO/Cu2O/MoC/Fe2O3 phase was obtained under ultrasound. According to the TEM and FESEM, sono-synthesized nanoparticles were rod-like with a width and length of 3nm and 40nm, respectively. Also, a well-dispersed shape and uniform morphology of nanoparticles were obtained using sonication. In comparison with the conventional nano-hybrid, this structure results in more void and accessible sites for adsorption of pollutants. The efficiency of resulting nanoparticles in adsorption of reactive dyes as a model of the pollutant was evaluated by sorption and sono-sorption processes. The sono-synthesized sample removed the pollutants more efficient than the conventional sample. The removal efficiencies were about 99% for the removal of reactive dyes using the sono-synthesized sample and sono-sorption method. Besides, determining factors including pH, pollutant concentration, temperature, and contact time were optimized in the sono-sorption and sorption processes. A colorimetric method based on RGB value was used to determine dye concentration in aqueous media. The images were taken by a smartphone and analyzed by ImageJ software. The accuracy of RGB results was confirmed by a UV-Vis spectrophotometer. Graphical abstract The figures on the left side show the FESEM images of nano-sorbent synthesized in the presence of ultrasonic irradiation (US method) and the absence of it (MS method). A well-dispersed shape and uniform morphology of nanoparticles were obtained using sonication. The scheme on the right side illustrates the process of sono-sorption for the removal of dyes and determination of their concentration using the colorimetric method. A colorimetric method based on RGB value was used to determine dye concentration in aqueous media. The graph shows the removal efficiencies of RY84 onto nanosorbent. The removal efficiencies were about 99% for the removal of reactive dye using the sono-synthesized sample and sono-sorption method.

Efficiency of novel Fe/charcoal/ultrasonic micro-electrolysis strategy in the removal of Acid Red 18 from aqueous solutions

Acid-Red 18 is one of many azo dyes that are widely used in the textile industry. Wastewater effluent stream may contain untreated dyes that are toxic, carcinogenic, or mutagenic in character and are harmful to marine life. Degradation of Acid-Red 18 was investigated by a hybrid micro-electrolysis process that included iron (Fe) and Charcoal(C) under the influence of Ultrasonic waves (Fe/C/US). The highest removal efficiency by the system (98.86 %) was at pH 7, initial concentration of dye 25 mg/L, Fe/C concentration at 1: 1 ratio of 10 g/L over 60 min. The Acid Red 18 mineralization amount was found to be 76.5 % under optimal condition and through Total Organic Carbon (TOC) analysis by (Fe/C/US). Thus, Fe/C/US system, used as an electrochemical oxidation process, has advantages such as high performance, lower cost, and effective, simple operation in eliminating and degradation of organic pollutants such as acid-red 18 from aqueous solutions.

Characterization of the wax precipitation in Iranian crude oil based on wax appearance temperature (WAT): The influence of ultrasonic waves

Abstract In this study, the effect of ultrasonic waves on the wax appearance temperature (WAT) of a crude oil sample was investigated. For this purpose, the crude oil was exposed to ultrasonic radiation at 2, 4, 6, 8, and 10 min. Then, the WAT of each sample was measured using the cross polarized microscope (CPM) method. The WAT was reduced to 8 °C and 12 °C at 4–8 min and 10 min, respectively. The origin of this reduction by ultrasonic radiation were studied by Fourier-transform infrared (FTIR) spectroscopy analysis. Because of the ultrasonic radiation, the first heavy crude compounds are cracked to lighter compounds, which reduces the side alkyl chain index in the FTIR spectra. Depending on the temperature of the crude oil after the irradiation, some light petroleum components, such as aliphatic components evaporated, resulting in the reduction of the aliphatic index calculated from the FTIR spectra. The wave radiation causes the wax crystals to become smaller, and their diameter dispersion reduces. The crystals were seen as rod-type before the irradiation, but the ultrasonic radiation caused the wax crystals to be rounded. Moreover, the wax crystals became morphologically more uniform. These waves, because of their high energy levels, cause changes in the percentage of saturate, aromatic, resin, and asphaltene (SARA) components of the crude oil, that are effective in altering the WAT. The aromatic compounds of the crude oil are pyrolyzed in two ways. First, in the presence of the saturate compounds, they are converted to resin. The resin, as a surfactant, reduces crystallization seeds in the oil and reduces the WAT point. Secondly, the aromatic compounds are first converted into the liquid saturate, and they evaporate if energy is supplied. The asphaltenes are also sensitive to pyrolysis by transferring energy into the oil and converting into the saturate compounds, especially methyl. Increasing the resin and light components within the structure of oil, such as paraffin, and reducing the aromatic and asphaltene compounds eventually reduced WAT. Finally, the shape of wax particles, isolated by IP143 method, was analyzed by scanning electron microscopy (SEM) imaging. The high-energy ultrasonic waves caused the average size of wax grains to reduce, the space between them to be greater, and the form of seeds changed from rounded to snow-like and irregular. Also, after the irradiation, bright spots were observed at the surface of the wax grains, which is related to the presence of heavy metals.

Study on ultrasonic techniques for enhancing the separation process of membrane

In this paper, the mechanism of enhanced membrane separation by ultrasound is analyzed. The main factors affecting the separation of enhanced membrane by ultrasonic technology is studied, the application and research progress of ultrasonic technology in membrane separation are studied. The conclusion are (a) cavitation caused by ultrasonic radiation is the main factor that increases the permeation flux of dextran solution (b) higher intensity of sound is helpful to the cleaning of the film; (c) ultrasound enhancement is related to temperature and operating pressure; (d) the film assembly shell material also affect the ultrasonic effect. In addition, the influence of ultrasonic wave on membrane structure is also discussed. Result indicates that the membrane separation process under the action of ultrasound does improve its permeability, but sometimes ultrasound can also cause damage to the membrane. Application of ultrasonic techniques for enhancing the separation process of membrane is also reviewed.