Effects Of Ultrasonic Time Research Articles

Preparation of PLA Nanoparticles and Study of Their Influencing Factors

Nanoparticles (NPs) have attractive properties that have received impressive consideration in the last few decades. Polylactic acid nanoparticles (PLA-NPs) stand out as a biodegradable polyester with excellent biocompatibility. This investigation introduces PLA-NPs prepared by using the emulsification-solvent volatilization (O/W) method. The effects of ultrasonication time, organic-to-aqueous phase volume ratio, surfactant Tween-20, and PLA on particle size as well as the polydispersity index (PDI) were investigated using a one-factor combination with Response Surface Methodology (RSM). The result indicates that, on the one hand, PLA was the key factor affecting particle size, which gradually increased as the amount of PLA increased from 0.01 to 0.1 g. The particle size of NPs gradually decreased as the surfactant Tween-20 increased from 0.25 mL to 1 mL in the aqueous phase. The volume ratio of the organic phase to the aqueous phase increased from 1:10 to 1:1, with the particle size initially decreasing (from 1:10 to 1:5) and subsequently increasing (from 1:5 to 1:1). As the ultrasonication time increased from 20 min to 40 min, the particle size initially increased (from 25 to 30 min) and then decreased (from 30 to 40 min). On the other hand, Tween-20 was the main factor of PDI, and with the increase of Tween-20, PDI changed significantly and increased rapidly. The volume ratio of the organic phase to the aqueous phase increased from 1:10 to 1:1, resulting in the stabilization and subsequent gradual decrease of the PDI. With the increase of ultrasonication time (20–40 min), PDI tended to be stable after the increase. The effect of PLA on PDI was not significant, and the change of PLA concentration did not cause a significant change in the size of PDI.

Effect of ultrasonication time on the performance of carbon black water nanofluid in solar absorption

This research reveals an innovative way of finding the ultimate time of ultrasonication that offers photothermal capability across carbon black (CB) water nanofluids, a great contribution to the field of solar energy absorption and nanofluid technology. The samples were generated using a two-step procedure with varying ultrasonication periods employed, ranging from 15 to 120 minutes, in concentrations of 0.005 wt% CB nanoparticles and 0.005 wt% sodium dodecyl sulfate (SDS) surfactant. Thirty days after preparation visible observation and UV spectroscopy, scanning electron microscopy (SEM) images, and particle size distribution were used to confirm the samples’ stability. The stability properties results demonstrated the beneficial effects of ultrasonication on the dispersion properties of nanofluids. Ultrasonication of less than 30 minutes resulted in the early sedimentation of nanoparticles. According to the results, the investigated nanofluids have high photothermal conversion capability with ultrasonication time. According to the findings, 30 minutes is the “optimal” ultrasonic duration to maximize photothermal conversion efficiency.

Study on the modulation of luminescence peak position and luminescence mechanism of black phosphorus

The application of black phosphorus in optoelectronic devices is hindered because of its inherent band gap characteristics. In the paper, black phosphorus was prepared by high-energy ball milling, and its related structure and properties were characterized. At the same time, the luminescence mechanism of black phosphorus was explored, and the effect of ultrasonic time on the structure and optical properties of black phosphorus was studied. The luminescence peak of black phosphorus can be modulated to the visible light range after adding polyethylene glycol, and the luminescence of black phosphorus is closely related to the P (020) and P (021). It was found that the luminescence intensity of alcoholized black phosphorus decreases with the increase of ultrasonic time. When the ultrasonic time is 15min, the luminescence intensity of alcoholized black phosphorus decreases greatly, this is because that the content of P (020) in black phosphorus decreases with the increase of ultrasonic time, resulting in the decrease of luminescence intensity.

Optimization of ultrasonic-assisted extraction of polyphenols from Salvia deserta Schang flowers based on response surface methodology and deep neural network and analysis of its in vitro antioxidant activities

This study aims to establish the optimization of ultrasound-assisted extraction for active compounds from Salvia deserta Schang flowers. The effect of ultrasonic time, ratio of liquid to material, ethanol concentration, and ultrasonic power on the extraction efficiency of total polyphenols and three phenolic compounds (e.g., rosmarinic acid, caffeic acid, and protocatechuic acid was investigated. Response surface methodology (RSM) and deep neural network (DNN) model was performed to find out the optimum extraction conditions to maximize the output using a comprehensive evaluation score in parallel. Compared with the DNN model, the optimal working conditions of the extraction procedures based on the RSM model achieves the maximum yield of active components in S. deserta Schang flowers while requiring a shorter extraction time, lower energy consumption, and greater cost effectiveness. The optimal extraction process for the active components of S. deserta Schang flowers was determined as follows: 39 min of ultrasonic time, 1:37 (g/mL) ratio of liquid to material, 55% ethanol concentration, and 200 W of ultrasonic power. Additionally, S. deserta Schang flowers exhibited promising antioxidative activity, which was verified through several in vitro antioxidant trials, including DPPH, ABTS, ·OH, and phosphomolybdate method, suggesting their remarkable antioxidant capacity. This findings contribute effective, sustainable and valuable insights into the ultrasonic-assisted extraction of valuable compounds from S. deserta Schang flower, and the more biological activity of compounds from S. deserta Schang flower remains to be further investigated.

THE EFFECT OF ULTRASONICATION TIME ON PARTICLE SIZE, POLYDISPERSITY INDEX AND STABILITY EVALUATION OF ANTHOCYANIN LIPOSOMES

Background: One of the drug delivery systems that acts as a targeting system is liposomes which have good characteristics so they can encapsulate and deliver drug compounds. One of the characteristics that need to be considered in liposomes is the particle size and polydispersity index. Several methods can be used to control these two characteristics, including the extrusion and the ultrasonication method. Objectives: This research aims to see stability evaluation and effect of ultrasonication time and extrusion on particle size and polydispersity index (PDI) of Anthocyanin liposomes. Methods: The liposome formula was prepared using Anthocyanin: DSPC: cholesterol: DSPE-PEG2000 in a ratio of 1: 1.85: 1: 0.15 using the ethanol injection method. Anthocyanin liposome was divided into 3 treatments of varying ultrasonication times i.e. 5 minutes (L1), 15 minutes (L2), and 30 minutes (L3), and extrusion method as control (L0). All methods of anthocyanin liposomes size and PDI were done the stability evaluation based on storage temperature i.e 4oC and 25oC for 6 weeks Results: The results of liposome characterization using particle size analyzer (PSA) showed that L0, L1, L2, and L3 had particle sizes of 152.1 nm, 150, 6 nm, 156.2 nm, 169.7 nm with the average PDI 0.379, 0.368, 0.450, 0.366 respectively. The statistical data (T-test) showed that there was no real influence on the particle size and PDI of Anthocyanin liposomes. However, Liposome treatment (L1) produced using the ultrasonication method for 5 minutes produces better particle size and PDI than other time variables. Moreover, the stability evaluation of anthocyanin liposomes size and PDI described the extrusion (control) and sonication method particularly 5 minutes of ultrasonication time were more stable than others due to no change size and PDI significantly at 4oC and 25oC for 6 weeks. Conclusion: Both methods can reduce the particle size of anthocyanin liposomes and have a homogeneous particle distribution, particularly the ultrasonication treatment time of 5 minutes which is the same as the extrusion method and and also more stable at storage temperatures of 4oC and 25oC for 6 weeks. Peer Review History: Received 8 December 2023; Revised 26 January 2024; Accepted 29 February; Available online 15 March 2024 Academic Editor: Dr. DANIYAN Oluwatoyin Michael, Obafemi Awolowo University, ILE-IFE, Nigeria, toyinpharm@gmail.com Average Peer review marks at initial stage: 5.0/10 Average Peer review marks at publication stage: 7.0/10 Reviewers: Dr. Md. Shahidul Islam, USTC, Chittagong, Bangladesh, S_i_liton@yahoo.com Dr. Mohammad Tauseef, Department of Pharmaceutical Sciences, College of Pharmacy, Chicago State University, mtauseef@csu.edu

Development and optimization of green extraction of polyphenols in Michelia alba using natural deep eutectic solvents (NADES) and evaluation of bioactivity

The development of bioactive natural products should take traditional as well as environmental factors into account to comply with the principles of green chemistry. This study evaluates the use of natural deep eutectic solvents (NADES) for polyphenols extraction from Michelia alba (M.alba). We compared the extraction performance of traditional solvents and screened nine different NADES for the tailored solution of M. alba. Environmental impact and extraction effectiveness were both taken into account throughout development. In order to save environmental resources in experiments, the effects of ultrasonic time, water content in NADES, and liquid-solid ratio on the extraction were investigated by single-factor experiments. These parameters were optimized by Box-Behnken design using response surface methodology. The optimum extraction conditions were 17.98 min of ultrasonic time, 48.52% of NADES water content, and 59.79 g/ml of liquid-solid ratio, which resulted in a high yield of 169.17 ± 0.19 mg/g. Morphological analysis of M. alba powder before and after extraction was carried out, and the findings indicated that the tailored NADES extraction technique provided a higher yield than the conventional extraction process. Additionally, The bioactivities of M. alba extraction are predicted with network pharmacology based on HPLC-MS/MS results and are further validated with cell experiments. Therefore, the green and high-efficiency method developed in this study provides a powerful tool that can utilize M. alba to its full potential and is environmentally friendly. The excellent bioactivities of M. alba extraction shown in this study suggest the potential value of M. alba extraction in pharmaceutical, cosmetics, and food additive applications.

Effects of ultrasonication time and solvent composition on physico–chemical properties of the pollen extract

Effects of ultrasonication time and solvent composition on physico–chemical properties of the pollen extract

Ultrasonic pretreatment-solvent extraction process for separating zinc from pickling waste liquid

Solvent extraction is the most important method for non-ferrous metals extraction and separation. In this work, solvent extraction of zinc from pickling waste liquid is investigated by using di(l-methyl heptyl) methyl phosphate (P350) diluted in sulfonated kerosene. Introduction of ultrasonic enhanced reduction of Fe3+ in the pretreatment stage of pickling waste liquid. The effect of ultrasonic time on the reduction process of Fe3+ is studied. Compared with traditional restoration, the required time for reduction is greatly shortened. The functional relationship of organic phase composition, concentration of extractant, phase contacts time and phase ratio function in single-stage extraction is studied. When concentration of extractant is 25 %, phase ratio is 4:1, the contact time is 15 min and the single-stage extraction efficiency of Zn2+ can reach 80.8 %. The extraction efficiency of Zn2+ reaches 99 % through three-stage countercurrent recovery. When O/A is 1:2, 1.6 mol/L HCl is used as the stripping agent and the stripping efficiency of P350 can reach 90.4 %. In addition, extraction stoichiometry is determined by slope analysis and extraction mechanism is analyzed by FT-IR and mass spectrometry. Overall, this work provides a new solution in the extraction of zinc from pickling waste liquid.

Experimental Study on Dissolution Stability and Dispersion and their Influence on Tribological Properties for Reducing Friction and Prolonging Life of Armored Vehicle Engine Lubricating Oil Additives

A lubricating oil additive for armored vehicle engine was synthesized by ultrasonic dispersion and physical blending with polyisobutylene and poly alpha olefin as polymer matrix, nanoBN and nanoALN as antifriction materials and polyisobutylene succinimide as surfactant. Polymer-based lubricating oil additive, hydroxyl magnesium silicate powder additive, commercial anti-wear repairing agent Goldway and commercial anti-wear protective agent Chief were dispersed into 10W-40 armored vehicle engine special lubricating oil according to a certain mass fraction. The dissolution stability of different lubricating oil additives in lubricating oil was investigated by standing test. The effects of ultrasonic time and temperature on the dispersion of different kinds of lubricating oil additives in lubricating oil are investigated by using ultrasonic disperser and particle size analyzer. The MDW-5G multifunctional end-face friction and wear tester is used to simulate the actual working process of cylinder liner-piston ring in armored vehicles during driving, and tribological tests were carried out under conventional working conditions to evaluate the tribological properties of different lubricating oil additives. Scanning electron microscope was used to measure and analyze the wear surface morphology and friction interface elements after tribological test, and the lubrication mechanism of lubricating oil additives is revealed. The results show that the polymer-based lubricating oil additive has good dissolution stability and dispersion in lubricating oil. Compared with pure lubricating oil, the average friction coefficient of lubricating oil containing 3wt% polymer-based additives is 0.085, and the friction coefficient decreases by 38.8%. During the friction process, polymer-based lubricating oil additives form a self-repairing oil film to cover the surface of the sample through a series of complex physical and chemical reactions, which reduces the friction and wear between the grinding pairs and improves the lubricating performance of lubricating oil.

Size optimization of nanoparticle and stability analysis of nanofluids for spectral beam splitting hybrid PV/T system

Spectral beam splitting hybrid PV/T system is a promising way to utilize effectively full spectrum solar energy for power and high-grade heat cogeneration. Heat medium liquid with nanoparticles (NPs) exhibits great potential in solar photothermal applications considering where using NPs to selectively absorb and transmit solar spectrum enables more efficient PV/T system. The paper begins with an introduction to the finite-difference-time-domain (FDTD) method system to analyze the full spectrum solar optical properties of SiO2 and TiO2 NPs. Moreover, taking spectral response of monocrystal silicon solar cells as example, the degree of appropriateness (DOA) was proposed to evaluate the response degree of NPs to specific bands of sunlight and optimize particle size. We suspend SiO2 and TiO2 NPs in Deionized water (DI) by two-step method to filter out the ideal spectrum for generating electricity from monocrystal silicon solar cells. The effects of ultrasonic time, ultrasonic power, and NPs/dispersants mass fraction ratios (MFR) on the stability of SiO2/water and TiO2/water nanofluids (NFs) were experimentally investigated based on static precipitation and absorbance methods. The results show that the optical properties are sensitive to the particle size of NPs and the extinction power increase with the increase of particle size. The particle size of TiO2 NPs in the range of 20-200 nm can regulate the position of extinction peak over a wide extent of 300-400 nm. The DOA of SiO2 and TiO2 NPs with particle size of 20 nm is the largest, which are 94.21% and 97.45%, respectively. The stability of SiO2/water and TiO2/water NFs is the best when Sodium Hexametaphosphate (SHMP) is added as dispersant. And the optimal MFR of NPs and SHMP is 1:1. The 0.05wt% SiO2/water NFs prepared has high stability at 250 W ultrasonic power and 50 min ultrasonic time. Moreover, the good stabilization of 0.01wt% TiO2/water NFs is achieved at 200 W ultrasonic power and 50 min ultrasonic time.

CO2 absorption and desorption enhancement by nano-SiO2 in DBU-glycerol solution with high viscosity

Nano-SiO2 was used to enhance the performance of CO2 absorption and desorption in viscous DBU-glycerol solution with a viscosity of about 60 mPa·s. The effects of ultrasonic time in the preparation of nanofluids, solids loading and particle/cluster size of SiO2 on absorbent properties and absorption performance were investigated. Meanwhile, the enhancements of heat transfer and mass transfer with nanoparticles in the desorption of CO2-loaded DBU-glycerol solutions were also analyzed. Proper ultrasonic vibration time and nano-SiO2 loading can both decrease the average particle size in the system which can improve the absorption. The increase of interfacial area between gas and liquid with the addition of nano-SiO2 dominates the enhancement of absorption and it has little effect on the enhancement factor when the nano-SiO2 size is 102 nm or below. But when the particle size is higher than 102 nm, the enhancement factor decreases with the increase of particle/cluster size. The addition of 0.10 wt% SiO2 nanoparticle with a particle size of 16 nm can increase the absorption rate by 31 % compared with base liquid. In desorption process, the desorption rate for CO2-loaded DBU-glycerol solutions can increase 18 % with the addition of 0.10 wt% nano-SiO2 with a particle size of 32 nm. The main reason could be that nano-SiO2 can improve the heating rate of the base fluid and supply plenty of nucleation sites for the formation of bubbles to improve the desorption rate. It shows that nano-SiO2 can be used to enhance both the absorption and desorption processes in solutions with high viscosity.

Microstructure and shear strength on ultrasonic-assisted soldered the Si/Cu joint using Sn-3.5Ag solder

The thermal stress, resulting from the big difference of CTE between Si and Cu, could reduce the strength of joints. In this study, Silicon and Cu were soldered by a two-step process (pre-metallization and brazing), which could alleviate the stress. Firstly, a Al-Si metallization layer (consisting α-Al matrix and Si phase) was prepared on the surface of monocrystalline Si by using Al metal powder at 900 ℃. Then the joint of pre-metallized Si and Cu was successfully achieved by ultrasonic-assisted soldering method with Sn-3.5Ag filler at 250 ℃ in air. The effects of ultrasonic time on microstructure and shear strength of the Si/Cu joints were investigated in details. It was found that the oxide layer was broken and gradually dissolved with the ultrasonic action, which was attributed to the high velocity (3055 m/s), high pressure (2.32×108 Pa), and the high temperature (5700 K) generated by the cavitation bubble collapse. Besides, the Ag2Al compounds and Si phases at the solder/metallization layer interface were observed. And the Cu6Sn5+Cu3Sn compounds were detected forming at the solder/Cu interface. As the ultrasonic vibration duration time increased, Ag2Al compounds attached to the Al-Si layer gradually increased, and ultimately entered into the filler. Attentionly, the maximum strength of Si/Cu joint was 32.4 MPa with the ultrasonic time of 6 s, and the fracture occurred inside the monocrystalline Si. The results show that ultrasonic action affects the distribution of Ag2Al compound and Si phase, which has an important influence on the joint strength.

Experimental Investigation of Thermal Conductivity of Water-Based Fe3O4 Nanofluid: An Effect of Ultrasonication Time.

Nanofluid preparation is a crucial step in view of their thermophysical properties as well as the intended application. This work investigates the influence of ultrasonication duration on the thermal conductivity of FeO nanofluid. In this work, water-based FeO nanofluids of various volume concentrations (0.01 and 0.025 vol.%) were prepared and the effect of ultrasonication time (10 to 55 min) on their thermal conductivity was investigated. Ultrasonication, up to a time duration of 40 min, was found to raise the thermal conductivity of FeO nanofluids, after which it starts to deteriorate. For a nanofluid with a concentration of 0.025 vol.%, the thermal conductivity increased to 0.782 W mK from 0.717 W mK as the ultrasonication time increased from 10 min to 40 min; however, it further deteriorated to 0.745 W mK after a further 15 min increase (up to a total of 55 min) in ultrasonication duration. Thermal conductivity is a strong function of concentration of the nanofluid; however, the optimum ultrasonication time is the same for different nanofluid concentrations.

Ultrasound-assisted preparation of chitosan/nano-silica aerogel/tea polyphenol biodegradable films: Physical and functional properties

In this study, chitosan(CS), nano-silicon aerogels(nSA) and tea polyphenols(TP) were used as film-forming materials and processed with ultrasonication to form films using the tape-casting method. The effects of ultrasonication time, temperature and frequency on the properties of CS/nSA/TP film were explored via material property testing. The results of response surface showed that the maximum tensile strength of the film was 4.036 MPa at ultrasonication time(57.97 min), temperature(37.26 °C) and frequency(30 kHz). The maximum elongation at break of the film was 279.42 % at ultrasonication time(60.88 min), temperature(39.93 °C) and frequency(30 kHz). Due to cavitation and super-mixing effects, ultrasonication may make the surface of the film smoother and easier to degrade. After ultrasonication, TPs were protected by the 3D network structure composed of CS and nSA. Ultrasonication improved the antioxidant and antibacterial properties of the film. These results show that ultrasonication is an effective method to improve the properties of films.

Synergistic effect of discrete ultrasonic and H2O2 on physicochemical properties of chitosan

Synergistic degradation of chitosan by discrete ultrasonic and H2O2 was investigated. The effects of ultrasonic time, ultrasonic power, chitosan concentration, and H2O2 concentration were evaluated. The results revealed that ultrasonic power, H2O2 concentration and ultrasonic time were positively correlated with degradation rate, while chitosan concentration was negative. The results of degradation kinetics revealed that the synergistic degradation process was consistent with the first-order reaction. Changes of characterization of chitosan were analyzed by FTIR, 13C NMR, XRD, SEM, and AFM analysis. The results indicated that the synergistic degradation did not destroy the pyranose ring. The crystal structure of degraded chitosan was destroyed, and the molecular conformation changed significantly. The antioxidant activity of the original and degraded chitosan was determined by DPPH and reducing power assays. The degraded chitosan had higher antioxidant activity. All results showed that the synergistic degradation of discrete ultrasound and H2O2 was a feasible method for large-scale low molecular weight chitosan production.

The Fractionation of Corn Stalk Components by Hydrothermal Treatment Followed by Ultrasonic Ethanol Extraction

The fractionation of components of lignocellulosic biomass is important to be able to take advantage of biomass resources. The hydrothermal–ethanol method has significant advantages for fraction separation. The first step of hydrothermal treatment can separate hemicellulose efficiently, but hydrothermal treatment affects the efficiency of ethanol treatment to delignify lignin. In this study, the efficiency of lignin removal was improved by an ultrasonic-assisted second-step ethanol treatment. The effects of ultrasonic time, ultrasonic temperature, and ultrasonic power on the ultrasonic ethanol treatment of hydrothermal straw were investigated. The separated lignin was characterized by solid product composition analysis, FT-IR, and XRD. The hydrolysate was characterized by GC-MS to investigate the advantage on the products obtained by ethanol treatment. The results showed that an appropriate sonication time (15 min) could improve the delignification efficiency. A proper sonication temperature (180 °C) can improve the lignin removal efficiency with a better retention of cellulose. However, a high sonication power 70% (840 W) favored the retention of cellulose and lignin removal.

Oxidative desulfurization utilizing activated carbon supported phosphotungstic acid in the frame of ultrasonication

Desulfurization technology is essential to remove sulfur content in diesel oil to achieve clean fuel products. In this study, oxidative desulfurization via ultrasonic bath equipment was utilized in conjunction with a synthesized activated carbon supported phosphotungstic acid (HPW-AC) catalyst. This research focuses on the extent of desulfurization in a simulated diesel oil. This contains 2.3% sulfur from benzothiophene (BT) and dibenzothiophene (DBT) mixed in actual diesel oil. The effects of ultrasonication time (30 min to 90 min), reaction temperature (40 °C to 70 °C), and catalyst dosage (6 wt% to 18 wt%) were examined for the oxidation of the simulated diesel oil containing BT and DBT. A 2k full factorial design was implemented in the experimental runs to evaluate the parameters by the analysis of variance. Results showed that the curvature of the model was not significant (p-value = 0.3134). Thus, further optimization runs were no longer required to fully analyze the model. The best conditions for sulfur conversion can be attained at 30 min, 70 °C and 18 wt% HPW-AC catalyst. Furthermore, the basic diesel oil properties (density, viscosity, and calorific value) were compared before and after the desulfurization treatment process. Results indicated that the simulated diesel oil retained essentially the same properties prior to its treatment. This proves to show a promising result that can further be improved for its applicability in future industrial practice.

Microstructure and enhanced joint performance of porous Si3N4 ceramics in ultrasonic soldering

Brazing is a commonly used method to join porous Si3N4 ceramics; it requires high temperature, long holding time, and vacuum environment. In this work, given the phenomena of sonocapillary and increased cavitation in narrow channels, ultrasonic-assisted soldering was successfully used to join porous Si3N4 ceramics at low temperature of 230 °C in the air within a short period. The effect of ultrasonic time on the microstructure and mechanical properties of the soldered joints was studied. The bonding mechanism of solder to ceramic was studied by scanning electron microscope, electron probe microanalyzer, and transmission electron microscope (TEM). Results showed that the Sn9Zn solder can infiltrate the microchannels of the porous Si3N4 ceramics through sonocapillary within a short ultrasonic time of 3 s. Prolonged ultrasonic time resulted in better wetting of solder to ceramic and wider infiltration layer. The infiltrated solder tightly bonded with the ceramic rod without pores and cracks. The TEM results showed that Zn and O were the main bonding elements. The bonding interface was characterized by nanocrystalline and amorphous ZnO. The shear tests revealed that prolonged ultrasonic time enhanced the joint strength.

Ultrasonic-assisted wetting and soldering of AlN ceramic by using a nonactive solder (Sn9Zn) in air

AlN ceramic was successfully wetted and then joined with nonactive Sn9Zn eutectic solder assisted by ultrasonication in air. The effect of ultrasonic time on the formation of joint was studied. Results indicated that the defect-free joint can be obtained at an ultrasonic time of 5 s. Two regions, namely, AlN/Sn (s,_s) and AlN/Zn (s,_s), were found in the bonding interface. Zn and O accumulated in the AlN/Sn (s,_s) interface. An amorphous and nanocrystalline layer of ZnO formed in the hard-wet AlN surface. And Zn (s,_s) directly bonded with AlN. The low temperature and fast bonding of the AlN was attributed to the high pressure and temperature caused by cavitation effect. The shear strength of the joint increased from 10.6 MPa to 30.7 MPa when the ultrasonic treatment time increased from 5 s to 150 s. With the prolongation of ultrasonic time, more AlN ceramic particles entered the solder and acted as the reinforcing phase. • AlN ceramic was rapidly wetted with a nonactive solder (Sn9Zn) in 5 s assisted by ultrasonication at 230 °C. • Wetting was realized by an amorphous and nanocrystalline ZnO at AlN/Sn interface, and Zn directly bonded with AlN. • The shear strength of the joint was 30.7 MPa with a short wetting time of 150 s. • The triggering mechanism of acoustic cavitation on wetting was analyzed through finite element simulation and calculation.

Effect of ultrasonic thawing on gel properties of tuna myofibrillar proteins

The effects of ultrasonication time (0, 6, 12, 18, and 24 min) at 280 W and ultrasonic power (0, 160, 280, and 400 W) for 12 min on properties of tuna myofibrillar protein (MP) gels were investigated. Gel qualities including gel strength, texture, water holding capability, and moisture migration were studied. The structure of MP gels was observed by sulfhydryl groups, surface hydrophobicity, ultraviolet absorption spectrum, particle size, and sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS–PAGE). The results showed that the protein structure maintains stabilization at 280 W for 12 min, and the quality of MP gels was improved after ultrasonic treatments. The r-value of the second-derivative UV spectra indicated that the microenvironment of the tyrosine was changed. In addition, the particle size decreased, and SDS–PAGE showed that myosin heavy chain and actin bands were degraded after ultrasonic treatments. These results indicated the potential for the further application of ultrasonic treatments in MP gels. Practical applications It is important to choose a suitable thawing method for frozen aquatic products. In order to reduce the quality fission of frozen products during the thawing, different ultrasonic powers and times were adopted in this work. The objectives of this study to evaluate the gel properties and structure of tuna myofibrillar proteins. The work showed that ultrasonic thawing is a feasible and effective method for frozen aquatic food.