Ultrasound Amplitude Research Articles

Characterization of yellowfin tuna (Thunnus albacares) skin gelatin extracted by bromelain hydrolysis and ultrasound pre-treatment.

Yellowfin tuna skin waste is a potential collagen source for gelatin through hydrolysis. Enzymatic hydrolysis is eco-friendly but expensive, necessitating efficiency improvements. Ultrasound pre-treatment enhances efficiency via cavitation effects. This study evaluated the effects of ultrasound amplitude, pre-treatment duration, enzyme concentration, and hydrolysis duration on yield; determined optimal conditions for ultrasound-assisted enzymatic extraction on yield, viscosity, and gel strength; and assessed the gelatin's physicochemical and functional properties. This research consists of three stages, factor screening using one variable at a time, optimization using response surface methodology with Box-Behnken design, and gelatin characterization. The study included three replicates. Screening identified factor ranges for optimization: 5-25 min pre-treatment, 1%-3% enzyme concentration, and 1-5h hydrolysis. Optimization involved 15 experimental runs, focusing on yield, viscosity, and gel strength. Optimal conditions were 25min pre-treatment, 1% enzyme concentration, and 2.17h hydrolysis, yielding 64.08%, 9.29 mPa·s viscosity, and 166.28 bloom gel strength. The optimized gelatin showed emulsifying properties with EAI 50.5 m2/g and ESI 23.80min, water-oil holding capacities of 192% and 406%, respectively, antioxidant activity of 60.16%, and molecular weight range of 17-160kDa. The amino acid composition was mainly glycine (29.26%) and proline (18.26%), with 76.95% digestibility. This innovative, environmentally friendly extraction method improved gelatin extraction efficiency from yellowfin tuna skin, supporting a sustainable industry.

Effect of ultrasound-assisted extraction on phenolic profile, bio-accessibility, OVCAR-3, and SKOV-3 cytotoxicity in blackthorn (Prunus spinosa L.).

This study aimed to examine the extraction of specific phenolic compounds from blackthorn using ultrasound-assisted extraction (UAE) and to evaluate the influence of UAE on the phenolic composition, bioaccessibility, and cytotoxic effect evaluated on ovarian cancer (OVCAR-3 and SKOV-3) and healthy (HaCaT) cell lines. The UAE parameters were optimized by modeling with the response surface method. Temperature, time, and ultrasound amplitude were utilized to determine the optimal extraction conditions. Optimization experiments were conducted to assess the influence of independent variables on the maximum concentrations of six phenolic compounds identified via high-performance liquid chromatography (HPLC) and the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity. The optimal conditions for UAE were determined as an extraction temperature of 33.177°C, a duration of 4.334 min, and an amplitude of 38.980%. The phenolic profile of the extract obtained under optimized UAE conditions (B-UAEopt) was re-examined, confirming that it remained consistent at the individual component level. Using an in vitro digestion model, UAE was found to increase the bioaccessibility of antioxidant activity in the small intestine. The IC50 values for OVCAR-3 were 64 and 67mg mL-1 for blackthorn and B-UAEopt, while the IC50 values for SKOV-3 were 53mg mL-1 and 50mg mL-1 for blackthorn and B-UAEopt, respectively. This study showed that UAE is an exceptionally effective method for extracting phenolic compounds from blackthorn, as it preserves the phenolic profile, enhances bioaccessibility, and maintains cytotoxic effects without any detrimental impact.

Extraction of chontaduro oil (Bactris gasipaes) for the synthesis of isopropyl esters through transesterification reactions assisted by ultrasound using green solvents

An experimental design study, using the Box-Behnken method with response surface methodologies (RSM), was conducted to evaluate the extraction process of chontaduro pulp (Bactris gasipaes) oil and its potential application in obtaining isopropyl esters through a transesterification process. The extraction of chontaduro oil and the transesterification reactions of the fatty esters were assisted by ultrasound techniques using n-hexane and isopropanol as environmentally friendly solvents. During the extraction process, the parameters evaluated were the sample to solvent ratio (w/w), power amplitude (%), and ultrasound pulse times (s). For the transesterification process, the parameters evaluated were ultrasound amplitude, ultrasound pulse time, and the amount of isopropanol (mol). The optimal conditions for the extraction process were found to be a sample to n-hexane ratio of 1:10 (w/w) and an ultrasound amplitude of 30%, with the pulse time not significantly affecting the oil yield of 15.02% achieved in a total time of 30 min. The predominant fatty acids in chontaduro oil were C18:1 cis oleic acid (54.31%) and C16:0 palmitic acid (20.40%). To synthesize isopropyl esters, we found that the ideal conditions are an ultrasound amplitude of 50%, an ultrasound pulse time of 20 s, and 0.4 moles of isopropanol. These conditions resulted in complete conversion within 45 min. The use of ultrasound radiation proved to be an alternative method to conventional techniques, reducing extraction and transesterification times, minimizing energy consumption, and increasing percentage yield. This contributes to green chemistry and the production of value-added products, potentially useful in the cosmetics industry.

CFD-based simulation of the hydrodynamics of steady-state gas–liquid in ultrasonically oscillating microreactors

Ultrasound-driven microbubble oscillation in a microchannel is commonly used in mixing and mass transfer, and its steady-state mechanisms are complex. This study proposes an acoustic streaming steady-state model for the oscillation between two microbubbles driven by ultrasound in a square microchannel (150 × 150 μm2). The breathing mode and shape oscillation mode of the bubble cap were experimentally analyzed at an ultrasound frequency of 97.5 kHz, and the flow patterns of liquid slugs were found to be completely opposite. A two-dimensional numerical model of the two microbubble oscillations was developed from a new perspective of steady state. The correctness of the model was verified by comparing the 2 μm diameter polystyrene tracer flow field with the simulation results. The steady-state flow field was analyzed in terms of ultrasound amplitude, shape, size, and liquid property parameters. The streaming velocity was found to be directly proportional to the square of the microbubble amplitude. When the bubble cap became more hydrophilic and sharper, the mixing effect improved. In particular, it was found that the microbubbles had the most intense disturbance to the fluid when the distance between the two microbubbles was twice the channel width.

Optimization of the conditions for immobilization of crude pectinase on chitin using ultrasound and glutaraldehyde and its application in grape juice clarification

The current research focuses on optimizing the immobilization of crude pectinase, produced by solid-state fermentation, onto chitin using ultrasound and glutaraldehyde as a crosslinking agent for grape juice clarification. A Box-Behnken design was used to model the effects of ultrasound time (5–15 min), ultrasound amplitude (20 – 60 %), and water-to-support ratio for ultrasound application (16−24) on immobilized crude pectinase activity and immobilization efficiency. Optimal conditions, comprising ultrasound time of 10 min, ultrasound amplitude of 20 %, and water-to-support ratio for ultrasound application of 24, yielded an immobilized crude pectinase activity of 2.19 IU/mL and 74 % immobilization efficiency. The immobilized crude pectinase showed improved kinetic properties and retained 69 % activity after three use cycles. Both free and immobilized crude pectinase enhanced juice clarity, reducing sugar, and TSS while lowering viscosity.

Effect of microstructure and texture gradient on the backscattered ultrasound amplitude of Ti-6Al-4V bars for aeroengine blade

The microstructure and texture gradient from the edge to the center of the Ti-6Al-4V bars, which is related to the deformation modes and processes, affects the backscattered ultrasound amplitude significantly. In this paper, radial forging and rolling were used to process Ti-6Al-4V bars for aeroengine blade. The microstructure and texture of the edge and center areas, as well as the backscattered ultrasound amplitude, were systematically studied. The edge area of the radial forged bar with strong {0002}<10–10> texture corresponds to an abnormal increase in backscattered ultrasound amplitude, while the highly <10–10>//AD textured center area corresponds to an extremely low backscattered ultrasound amplitude. The abnormal increase in backscattered ultrasound amplitude was also observed in the edge of rolled bar, which has a texture similar to the center of radial forged bar. In industrial production, this abnormal increase of backscattered ultrasound amplitude often leads to exceeding the standards of titanium bars for blade. The relationship of process-texture-backscattered ultrasound amplitude was analyzed, and the mechanism of the abnormal increase of backscattered ultrasound amplitude was discussed. The results indicated that the backscattered ultrasound amplitude is related to the shape of the grains, the intensity and type of texture, and the formation of macrozones. Based on these researches, several methods were used to adjust the backscattered ultrasound amplitude of Ti-6Al-4V bars for aeroengine blade, which were effective and met the requirements of standards.

Optimisation of Non-Thermal Ultrasonication Process for Retaining Nutritional Quality in Cow Milk: Effects of Fat Percentage and Treatment Parameters

The thermal unit operation used in milk processing causes changes in milk nutritional quality. Hence, optimising the non-thermal ultrasonication process at 25°C can be a potential method to retain milk quality. The objective of this research is to optimise the ultrasonication process of standardised fresh cow's milk at various fat percentages and elucidate its effect on nutritional values using response surface methodology (RSM). A central composite design based on fat (1–4%); ultrasound amplitude (10–70%), and sonication time (1.5–10.5 min) was used. Data analysis shows that the ultrasonication process significantly (p&lt;0.05) affects the percentage of fat, free fatty acid (FFA), protein, solid non-fat; solid non-fat (SNF), lactose, casein, and total solid (TS). The adjusted R2 for fat, free fatty acid, and TS with goodness-of-fit were 0.940, 0.975, and 0.955, respectively. The generation of FFA in raw cow milk was observed with some ultrasonication conditions. As a conclusion, the processing parameters to get the highest fat and lowest FFA is a combination of 4% milk fat, 10% amplitude, and 1.95 min sonication time with 46.8 J/mL energy density can be applied to control the release of further FFA generation from the milk processing line.

A novel deep eutectic solvent-based green extraction and purification of DPP-IV inhibitory peptides from tilapia (Oreochromis niloticus) viscera hydrolysate

The use of green and low-cost techniques to produce bioactive peptides with anti-diabetic properties from protein-rich fish waste is a sustainable way to manage agro-fishery and food industrial waste. This study investigated a novel ultrasound (UL) assisted deep eutectic solvent (DES) based extraction approach to recover bioactive protein-rich extracts from tilapia fish viscera waste under optimized conditions (52.52% ultrasound amplitude, 1:4 DES molar ratio, 25 min extraction time). The aqueous two-phase system (ATPS) method successfully concentrated the crude proteins in the top phase and back-extracted proteins to the bottom phase with a high recovery yield. Hydrolysis by Alcalase produced tilapia viscera protein hydrolysate (TVPH) with low molecular weight (MW) peptides and low dipeptidyl peptidase (DPP)-IV half-maximal inhibitory concentration (IC50) value of 1.57 ±0.16 mg/mL. Notably, TVPH-3 fraction and TVPH-3-2 sub-fraction exhibited appreciable DPP-IV IC50 values of 1.36 ±0.08 mg/mL and 0.42 ±0.01 mg/mL, respectively. Ultrafiltration combined with RP-HPLC enriched the DPP-IV inhibitory concentration of the individual protein fractions. TVPH-3-2 sub-fraction contained hydrophobic amino acids and peptide sequences with typical DPP-IV inhibitory peptide sequence motifs. The results presented in this study indicate that tilapia viscera biomass is a potential source for protein recovery aided with a green extraction approach, and tilapia viscera protein-derived hydrolysates have potential applications as a potent functional food ingredient for the management of metabolic diseases like type-2 diabetes.

Ultrasound-Assisted Extraction of Chickpea Proteins and Their Functional and Technological Properties

Research background. Chickpea is a very good source of protein for the development of protein-enriched plant-based ingredients. Chickpea protein isolates are primarily obtained by wet extraction methods such as alkaline or salt extraction. The energy input required for the production of chickpea protein isolates can have an impact on both the environment and processing, thus affecting nutritional quality and human health. Therefore, further research is needed to develop mild processing techniques for the isolation of chickpea proteins. Experimental approach. In this study, with the aim of developing a more efficient and effective method, chickpea proteins were isolated by ultrasound-assisted extraction and the process parameters were optimised using the Box-Behnken design. Results and conclusions. Under the optimal extraction conditions (solid/solvent ratio 13.42 g/100 mL, pH=8.8, extraction time t=10 min, ultrasound amplitude 70 %), the highest extraction yield was obtained, 66.1 % with ultrasound-assisted extraction and 55.1 % with the conventional alkaline method. When comparing the ultrasound-assisted method with the conventional alkaline method, it was found that a higher protein isolation yield was obtained with a 6-fold shorter processing time and a 29-fold lower energy consumption. Moreover, it was found that the water/oil absorption properties of the protein isolate obtained by the ultrasound-assisted method increased and its foaming properties improved. Novelty and scientific contribution. This research presents a feasible ultrasound-assisted extraction technique for the isolation of chickpea protein, which can then be used as a versatile ingredient in the food industry.

Physicochemical characterization of Dillenia indica fruits and exploration of extraction methods to obtain reducing compounds and pectin

Dillenia indica Linn. is an unconventional edible plant with numerous health benefits, including anti-diabetic, anti-inflammatory, and anticancer properties. Dillenia indica fruit, known as elephant apple, is rich in nutrients and bioactive compounds and is an excellent source of pectin, a polysaccharide extensively used in the food industry. Despite the potential of this plant, it has been little studied and is still under-explored for commercial purposes. This study aimed to explore methods for extracting total reducing compounds and pectin from Dillenia indica fruit. First, the extraction of reducing compounds was optimized by ultrasound-assisted method within an experimental design considering three variables: solvent-to-feed (S/F) ratio (10:1 – 30:1), ethanol-to-water ratio (0:100 – 100:0) and ultrasound amplitude (24 – 40 %). In the following step, kinetic curves at the optimized conditions were obtained for up to 16 min. The ultrasound-assisted method was then compared to mechanical stirring (100 rpm). In the last step, pectin was extracted, maintaining the same S/F ratio (30:1) and ethanol-to-water ratio (20:80), but using magnetic stirring, pH 2.0, and 80 ºC. Pure water at pH 2.0 was used as a solvent for comparison. In the ultrasound-assisted extraction, the optimal yield was achieved with an S/F ratio of 30:1, an ethanol-to-water ratio of 20:80, and an ultrasound amplitude of 24 %. In the kinetic curves, a higher reducing capacity was obtained at 8 min through mechanical stirring. The pectin extraction was more effective with pure water (12.1 %). However, the ethanol-water mixture promoted a similar amount of pectin (10.3 %) but with a considerably higher total reducing capacity (25.82 mg GAE/g for ethanol-water and 14.5 mg GAE/g for pure water). These results demonstrated that reducing compounds and pectin can be effectively extracted from Dillenia indica fruit, highlighting the potential of this fruit to produce valuable ingredients.

Ultrasound as Green Technology for the Valorization of Pumpkin Leaves: Intensification of Protein Recovery.

The recovery of valuable nutritional compounds, like proteins, from waste streams and by-products is a key strategy for enhancing production sustainability and opening up new market potential. This research aimed to use high-intensity ultrasound as an innovative technique to extract the soluble proteins from the pumpkin leaves. The impact of various sonication amplitudes and duration periods on protein yield, functional properties, antioxidant qualities, and structural characteristics, were studied. Utilization of ultrasound technology significantly increased the yield of pumpkin leaf protein by up to 40%-six times higher than maceration. The ultrasound extraction provided a RuBisCO-rich protein fraction with high radical scavenging and chelating activities, especially at 40% amplitude. Cavitation modified the tertiary and secondary structures of leaf proteins: the amount of α-helix changed based on amplitude (12.3-37.7%), the amount of random coil increased to 20.4%, and the amount of β-turn reduced from 31 to 18.6%. The alteration of the protein fluorescence spectrum (blue shift in spectrum) provides further evidence that ultrasound alters the proteins' molecular structure in comparation with maceration; the maximum tryptophan fluorescence intensity decreased from 22.000 to 17.096. The hydrophobicity values of 76.8-101.5 were substantially higher than the maceration value of 53.4, indicating that ultrasound improved the hydrophobicity of protein surfaces. Ultrasound resulted in a significant increase in solubility in an acidic environment with the increase in sonication amplitude. A 2.4-fold increase in solubility at pH 2 becomes apparent (20% amplitude; 43.1%) versus maceration (18.2%). The emulsifying ability decreases from 6.62 to 5.13 m2/g once the sonication amplitude increases by 20-70%. By combining the ultrasound periods and amplitudes, it is possible to create high-value protein leaf extracts with improved properties which can find real application as food additives and dietary supplements.

Characterization of industrial pea canning by-product and its protein concentrate obtained by optimized ultrasound-assisted extraction

This work aimed to optimize protein extraction from an industrial pea canning by-product by developing an ultrasound-assisted alkaline solubilization and isoelectric precipitation method. Proximate composition and microbial contamination (total bacterial count, total lactic acid bacteria, Enterobacteriaceae, yeasts and moulds) were assessed in the wet by-product. The protein concentrate obtained, the dry by-product and a commercial pea flour were analysed for protein content, water activity, colour and techno-functional properties. The optimal extraction conditions from the wet by-product were liquid-solid ratio 20 mL/g, pH 11, ultrasound amplitude 80 μm, time 2 × 30 min. The extraction from the dry by-product was not feasible. Sonication reduced extraction time from 4 h (magnetic stirring method) to 1 h and increased three-fold the extraction recovery (from 21.5% to 66.6%). The concentrate had a 74.8 g/100 g DM protein content. The SDS-PAGE revealed protein degradation in some specimens, probably because of fermentation and enzymatic hydrolysis before sampling. However, the microbial counts in the concentrate, mainly related to lactic acid bacteria, were always below the guideline values. Our results demonstrate that the pea canning by-product is a valuable raw material for protein recovery and that the proposed method allows rapid and direct treatment, avoiding drying costs and microbial proliferation.

Bioactive, Pro-Apoptotic-Angiotensin Converting Enzyme Inhibitor Effects and Properties of Ultrasound-Treated Traditional Poppy Vinegar Using the Response Surface Methodology Model.

Poppy vinegar with functional properties is a fermented product. This study evaluated traditionally produced poppy vinegar. The study was conducted on poppy vinegar to determine the maximum increase in angiotensin converting enzyme (ACE) inhibitory activity %, total phenolic content (TPC), and radical scavenging activity (DPPH) of the vinegar at different combinations of ultrasound treatment duration (2-14 min) and amplitude (40-100%). The optimal parameters obtained using the response surface methodologies (RSM) were the duration of the ultrasound of 5.5 min and the amplitude of the ultrasound at 57%. When the DPPH values, ACE inhibition %, and TPC and DPPH values obtained with the RSM model were compared with the experimental values, the difference was 9.80, 3.0, and 4.6%, respectively, showing good agreement between actual and predicted values. The higher ultrasound intensities and longer treatment times had a significant effect on antioxidant activity. Poppy vinegar samples significantly induced the apoptosis of lung cancer cells, particularly those stored for 6 and 12 months. The amounts of protocatechuic acid, gallic acid, neohesperidin, hydroxybenzoic acid, resveratrol, rutin, trans-cinnamic acid, quercetin, and flavon in poppy vinegar were determined, which decreased significantly as storage time increased. TPC and TFC were determined to be 90.39 mg of GAE/100 mL and 29.86 mg of TEAC/mL, respectively, and there was no significant change in these bioactive compounds after 6 months of storage. The highest value of ACE inhibitory activity was found at the beginning of the storage period. The present study was the first study to examine the bioactive components, ACE inhibition activity, pro-apoptotic activities, and phenolic composition of traditionally produced ultrasound-treated poppy vinegar during storage. The control of production parameters and the design of ideal poppy vinegar fermentation processes could benefit from this research.

Optimization of Phenolic Compounds Extraction from Aerial Parts of Fabiana punensis S. C. Arroyo by Ultrasound- and Microwave-Assisted Extraction.

Fabiana punensis S. C. Arroyo is a subshrub or shrub that is indigenous to the arid and semiarid region of northern Argentina and is known to possess several medicinal properties. The objective of this study was to optimize the extraction conditions so as to maximize the yield of bioactive total phenolic compound (TPC) and flavonoids (F) of F. punensis' aerial parts by using non-conventional extraction methods, namely ultrasound-assisted extraction, UAE, and microwave-assisted extraction, MAE, and to compare the biological activities and toxicity of optimized extracts vs. conventional extracts, i.e., those gained by maceration. Response Surface Methodology (RSM) was used to apply factorial designs to optimize the parameters of extraction: solid-to-liquid ratio, extraction time, ultrasound amplitude, and microwave power. The experimental values for TPC and F and antioxidant activity under the optimal extraction conditions were not significantly different from the predicted values, demonstrating the accuracy of the mathematical models. Similar HPLC-DAD patterns were found between conventional and UAE- and MAE-optimized extracts. The main constituents of the extracts correspond to phenolic compounds (flavonoids and phenolic acids) and apigenin was identified. All extracts showed high scavenger capacity on ABTS•+, O2•- and H2O2, enabling the inhibition of the pro-inflammatory enzymes xanthine oxidase (XO) and lipoxygenase (LOX). They also showed an antimutagenic effect in Salmonella Typhimurium assay and cytotoxic/anti-proliferative activity on human melanoma cells (SKMEL-28). Toxicological evaluation indicates its safety. The results of this work are important in the development of efficient and sustainable methods for obtaining bioactive compounds from F. punensis for the prevention of chronic degenerative diseases associated with oxidative stress, inflammation, and DNA damage.

Stabilization of Eversa® Transform 2.0 lipase with sorbitol to enhance the efficiency of ultrasound-assisted biodiesel production

Ultrasound technology has emerged as a promising tool for enhancing enzymatic biodiesel production, yet the cavitation effect induced can compromise enzyme stability. This study explored the efficiency of polyols in enhancing lipase stability under ultrasound conditions to further improve biodiesel yield. The incorporation of sorbitol resulted in the highest fatty acid methyl ester (FAME) content in the ultrasound-assisted biodiesel production catalyzed by Eversa® Transform 2.0 among the investigated polyols. Furthermore, sorbitol enhanced the stability of the lipase, allowing it to tolerate up to 100 % ultrasound amplitude, compared to 60 % amplitude in its absence. Enzyme activity assays revealed that sorbitol preserved 99 % of the lipase activity, in contrast to 84 % retention observed without sorbitol under an 80 % ultrasound amplitude. Circular dichroism (CD) and fluorescence spectroscopy analyses confirmed that sorbitol enhanced lipase rigidity and preserved its conformational structure under ultrasound exposure. Furthermore, employing a stepwise methanol addition strategy in ultrasound-assisted reactions with sorbitol achieved an 81.2 wt% FAME content in 8 h with only 0.2 wt% enzyme concentration. This promising result highlights the potential of sorbitol as a stabilizing agent in ultrasound-assisted enzymatic biodiesel production, offering a viable approach for enhancing biodiesel yield and enzyme stability in industrial applications.

Investigating ultrasonic dispersion of nanostructured silica for nanocomposite materials application

This article presented the results of investigating the influence of ultrasonic dispersion of nanostructured silica that has been referred to nanosilica (n-SiO2) into unsaturated polyester (UPE) resin for nanocomposite materials application. Scanning electron microscopy (SEM) method was employed to analyze the dispersion characteristics in this work. The optimally suitable ultrasonic factors have been identified including ultrasound frequency amplitude of 60%, ultrasound time of 120 minutes. Also, the bending strength measurement results of nanocomposite samples have shown that nanosilica material addition has increased significantly the mechanical properties of the nanocomposite material based on UPE resin. This also has shown the possibility of using n-SiO2 as a reinforcing agent for nanocomposite materials applications.

Design and process optimisation of double emulsions loaded with casein hydrolysate

Water-in-oil-in-water (W1/O/W2) emulsions show promise for encapsulating hydrophilic active substances. However, the low stability of W1/O/W2 hinders its use for encapsulation purposes, and peptide encapsulation has challenges due to its surface-active properties. This study aimed to determine the appropriate formulation based on turbidity and encapsulation efficiency, as well as the optimal production parameters (ultrasound amplitude and time) for double emulsions containing casein hydrolysate, with a focus on the second homogenisation stage. Double emulsions were produced with three different emulsifiers (polysorbates 20, 60, or 80) at different concentrations (0.25%, 1%, or 1.75%) and dispersed phase ratios (10%, 20%, or 30%) using an ultrasound homogeniser. The results indicated that dispersed phase ratios and emulsifier concentrations had higher impact on emulsion properties than emulsifier types. A stable emulsion with high encapsulation efficiency was achieved with 1% polysorbate 20 and a 30% dispersed phase ratio, using sonication at 54% amplitude for 66 s.

Effects on quality characteristics of ultrasound-treated gilaburu juice using RSM and ANFIS modeling with machine learning algorithm

Gilaburu (Viburnum opulus L.) is a red-colored fruit with a sour taste that grows in Anatolia. It is rich in various antioxidant and bioactive compounds. In this study, bioactive compounds and ultrasound parameters of ultrasound-treated gilaburu water were optimized by response surface methodology (RSM) and adaptive neuro-fuzzy inference system (ANFIS). As a result of RSM optimization, the independent ultrasound parameters were determined as an ultrasound duration of 10.7 min and an ultrasound amplitude of 53.3, respectively. The R2 values of the RSM modeling level were 99.93%, 98.54%, and 99.80%, respectively, and the R2 values of the ANFIS modeling level were 99.99%, 98.89%, and 99.87%, respectively. Some quality parameters of gilaburu juice were compared between ultrasound-treated gilaburu juice (UT-GJ), thermal pasteurized gilaburu juice (TP-GJ), and control group (C-GJ). The quality parameters include bioactive compounds, phenolic compounds, minerals, and sensory evaluation. Bioactive compounds in the samples increased after ultrasound application compared to C-GJ and TP-GJ samples. The content of 15 different phenolic compounds was determined in Gilaburu juice samples, and the phenolic compound of UT-GJ samples increased compared to TP-GJ and C-GJ samples, except for gentisic acid. Ultrasound treatment applied to gilaburu juice enabled its bioactive compounds to hold more in the juice.

Effect of the void and crack quantity and location on ultrasound: resin experiments and carbon brick validation

ABSTRACT In industrial applications, there is a lack of methods applicable to large-scale, rapid and non-destructive detection of voids and cracks inside carbon bricks. This paper used the ultrasonic testing (UT) A-scan method to investigate the influence of quantity (void fraction:1.4%-4.6%; number of artificial cracks:1–7) and location (five layers) of voids and cracks inside the resin on ultrasonic waves. Both fast Fourier transform (FFT) and synchrosqueezed wavelet transform (SWT) are employed to analyse the amplitude, main frequency and normalised peak time of ultrasonic waves. The results indicate that increased void fraction and number of cracks lead to greater amplitude attenuation, promoting the transition from the fundamental wave to harmonics. Void and crack location symmetrically affect ultrasound amplitude, main frequency, and normalised peak time around the sample centre. Meanwhile, fitting equations are established for the main frequency of the fundamental wave (f 1) in relation to defect quantity. A high-precision quantitative defects detection standard is also developed based on normalised peak time. The validation based on carbon bricks indicates that the derived empirical relations between these parameters and defects can lay the foundation for large-scale and rapid non-destructive detection in carbon bricks.

An ultrasonic fabrication process for carbides reinforced Inconel 718 alloy composites

A novel approach was proposed to prepare carbides reinforced Inconel 718 alloy composites by ultrasonicating graphite mold to introduce carbon element into liquid phase. The graphite mold was designed to resonate with three-dimensional (3D) power ultrasounds, which stimulated cavitation effect and acoustic streaming to promote uniform carbon dispersion and the subsequent incorporation of various carbides with alloy solidification process. It was found that the carbon content infiltrated into liquid alloy increased with ultrasound amplitude and dimension, which attained the maximum of 2.64 wt% C. Ultrasound accelerated the peritectic L+TiC→NbC reaction, forming a blocky (Ti, Nb)C phase instead of shell-core structured (TiC+NbC) phases. A new (Cr, Fe)7C3 phase was produced due to the extended carbon solubility into liquid alloy under 3D ultrasounds. Meanwhile, the synergistic orientation relationships between γ(Ni) and carbide phases were enhanced by high-frequency vibration. The ultrasonically solidified composites exhibited excellent wear resistance and hardness as compared with other IN718 alloy-based composites.