Ultrasound Assistance Research Articles

A Comparison of Conventional and Ultrasound-Assisted BCR Sequential Extraction Methods for the Fractionation of Heavy Metals in Sewage Sludge of Different Characteristics.

The purpose of this study was to determine the heavy metal (HM: Cd, Cr, Cu, Ni, Pb, Zn, and Hg) content in particular chemical fractions (forms) of sewage sludge with different characteristics (primary and dewatered sludge) using conventional (CSE) and ultrasound-assisted (USE) BCR sequential extraction methods (Community Bureau of Reference, now the Standards, Measurements and Testing Programme). The concentrations of HMs were determined using inductively coupled plasma optical spectrometry (ICP-OES). Only mercury was assayed with cold vapor atomic absorption spectrometry (CVAAS). Ultrasound treatment was conducted in the ultrasonic bath (Sonic 5, Polsonic). The optimal sonication time (30 min) was determined using ERM-CC144 (Joint Research Center; JCR) certified reference material. The conducted experiment revealed that the use of ultrasound waves shortened the extraction time to 4 h and 30 min (Stages I to III). The recoveries (RM) of heavy metals ranged from 62.8% to 130.2% (CSE) and from 79.8% to 135.7% (USE) for primary sludge, and from 87.2% to 113.2% (CSE) and from 87.8% to 112.0% (USE) for dewatered sludge. The only exception was Hg in dewatered sludge. The conducted research revealed minor differences in the concentrations and fractionation patterns for Cd, Ni, and Zn extracted from sludge samples by the tested methods. However, it was confirmed that the above findings do not significantly affect the results of a potential ecological risk assessment (with minor exceptions for Cd and Zn in the primary sludge), which is extremely essential for the natural use of sludge, and especially dewatered sludge (the final sludge). The shorter extraction time and lower energy consumption prove that ultrasound-assisted extraction is a fast and simple method for HM fractionation, and that it provides an alternative to the conventional procedure. Therefore, it can be considered a “green method” for the assessment of the bioavailability and mobility of heavy metals in solid samples.

Ultrasound enhanced butyric acid-lauric acid designer lipid synthesis: Based on artificial neural network and changes in enzymatic structure

Ultrasound is a green technology for intensifying enzymatic reactions. In this study, an ultrasonic water bath with equipment parameters of 28 kHz, 1750.1 W/m2, 60% duty cycle was used to assist the synthesis of butyric acid-lauric acid designer lipid (BLDL), which was catalyzed by Lipozyme 435. A convincing three-layer feed-forward artificial neural network (ANN) model was established (R2 = 0.949, RMSE = 4.759, ADD = 7.329) to accurately predict the optimal parameters combination, which was described as 13.72 mL reaction volume, 15.49% enzyme loading, 0.253 substrate molar ratio (tributyrin/lauric acid), 56.58 °C reaction temperature and 120 min reaction time. The ultrasonic assistance increased actual butyric acid conversion rate by 11.38%, and also enhanced the consumption rate of tributyrin and lauric acid during the reaction. Meanwhile, the esterification activity of Lipozyme 435 was enhanced and its effectiveness up to 6 cycles. Structurally, ultrasound assistance significantly disrupted the secondary structure of the Lipozyme 435: reduced the content of α-helices, increased the content of β-sheet and β-turn. In addition, sonication caused an increase in crevice and micro-damage on the surface of the immobilized enzyme. In conclusion, low-intensity ultrasound at 28 kHz improved the synthesis efficiency of BLDL, which was scientifically predicted by ANN model, and the change of enzyme structure may be the vital reason for ultrasound enhanced reaction. However, the effect of ultrasound on immobilized enzymes’ activity needs to be further explored.

Measurement of microstructural changes promoted by ultrasound application on plant materials with different porosity

This research investigated the effects of ultrasound application (192 ± 6 W/L) on the microstructure of vegetables/fruits with different porosities, cell sizes and patterns (eggplants, beetroots, and apples), submitted to an immersion treatment in different liquids: distilled water, citric acid (1% w/v), and the vegetable/fruit juice, at 25 °C during 5 min. The ultrasound application did not significantly (p > 0.05) affect the size of the cells of the most porous material (eggplant) compared to the samples immersed without ultrasound assistance. The apple samples (with a middle-high porosity and the largest cells) were the most affected by ultrasound application. The median cell areas of samples treated with ultrasound in water and apple juice were 26 and 20% larger than those of samples treated without ultrasound, mainly because of cell wall disruption which caused the cells to merge into bigger clusters, but no effect was observed with the citric acid. Ultrasound application significantly (p < 0.05) increased the median cell area of the less porous raw matter (beetroot) only when the treatment was carried out in the vegetable juice (cells were 26% larger after treatment assisted with ultrasound than without it). Thus, the effects of ultrasound differ in materials with initially different characteristics.

Fresh keeping mechanism of Fenneropenaeus chinensis by ultrasound‐assisted immersion freezing: Effects on microstructure and quality changes

The fresh keeping ability of ultrasound-assisted immersion freezing (UIF), immersion freezing (IF), and refrigerator freezing (RF) was compared in Fenneropenaeus chinensis (F. chinensis). Observation of muscle microstructure indicated that UIF treatment had the smallest ice crystals formation with uniform distribution, resulting in minimal damage to muscle tissues. Meanwhile, UIF-treated F. chinensis showed slower pH change, lower values of total volatile basic nitrogen (TVB-N), and thiobarbituric acid reactive substances (TBARS). The higher values of salt soluble protein content，Ca2+-ATPase activity, and water-holding capacity revealed that UIF could inhibit protein degeneration and moisture loss. In addition, an excellent sensory evaluation score also verified the efficient fresh keeping capacity of UIF. Our results indicate the potential of UIF in maintaining the freshness and quality of F. chinensis during frozen storage. Novelty impact statement Preservation effects of different freezing methods to Fenneropenaeus chinensis were compared. Ultrasound-assisted immersion freezing caused less tissue damage to shrimp and could inhibit the spoilage during frozen storage. Ultrasound assistance is efficient for the fresh keeping of aquatic products.

Valorization of sugar beet molasses powder by microwave and ultrasound‐assisted extractions of bioactive compounds: An optimization study

Sugar beet molasses is one of the most important by-products of the sugar industry. The present study investigates the optimization of microwave-assisted (MAE) and ultrasound-assisted (UAE) extraction conditions of sugar beet molasses powder in terms of total phenolic content (TPC), total flavonoid content (TFC), free radical scavenging activity of 1,1-diphenyl-2-picrylhydrazyl (DPPH), and ferric reducing antioxidant power (FRAP). A three factor, and three level Box–Behnken design was used to optimize microwave power, extraction time, and methanol concentration conditions for MAE and ultrasound amplitude, extraction time, and methanol concentration for UAE. The optimal MAE parameters were a microwave power of 420 W, an extraction time of 70 s, and a methanol concentration of 30%. For UAE, an amplitude level of 90%, an extraction time of 300 s, and a methanol concentration of 46% were determined as optimal conditions. Novelty impact statement Sugar beet molasses is one of the most important by-products of sugar production. Giving the molasses in powder form is practical in many ways, for example, in use, storage, and sampling. There is no other study in which ultrasound and microwave-assisted extraction using RSM has been optimized to extract bioactive components from sugar beet molasses powder. This study demonstrated that microwave-assisted extraction is a more effective method for extracting bioactive compounds from sugar beet molasses powder than ultrasound-assisted extraction.

Removal of methylene blue from water by ultrasound-assisted adsorption using low-cost bentonites

This study focused on the comparison of ultrasound-assisted (UA) and conventional (shaking or stirring) adsorption techniques, taking into account the time-dependent adsorption capacities. Six different bentonite samples were used as adsorbents, and methylene blue (MB) was used as adsorbate. Effects of pH, contact time, MB initial concentration, and temperature on the UA-adsorption were also investigated. XRD analyzes showed that all the bentonite samples were mostly composed of montmorillonite clay minerals, while XRF analyzes showed that the samples contained high percentage of silicon and aluminum oxides (≥70 wt%). Maximum zeta potential values (37.1–42.1 mV) were measured at pH 12 and, to confirm this, maximum adsorption capacities were also determined at this point. Ultrasound irradiation significantly increased the adsorption capacities of all bentonite samples in the early stages. For example, the adsorption capacity of the B-1 bentonite sample was measured as 388 mg/g by UA-adsorption at the first 5th minute, while it was 286 mg/g by conventional (C) adsorption technique at the same time. All bentonite samples showed increasing adsorption capacity with increased temperature confirming endothermic reaction. Maximum adsorption capacities of B-1, B-2, B-3, B-4, B-5, and B-6 bentonite samples with the 96–100 % MB removal percentages at selected conditions (pH: 11–12, temperature: 25 °C, contact time: 60 min, and MB initial concentrations for B-1: 800, B-2: 700, B-3,4: 650, B-5: 600, and B-6: 500 mg/L) were measured as 398, 342, 320, 296, 288, and 243 mg/g, respectively. Pseudo-second-order kinetic model and Langmuir isotherm model with higher correlation coefficients were found to be more suitable to explain the adsorption of MB cations onto bentonites. In addition, maximum adsorption capacities of B-1, B-2, B-3, B-4, B-5, and B-6 samples at 25 °C calculated from Langmuir isotherm data determined as 500, 454.5, 400, 384.6, 370, and 357.1 mg/g, respectively.

Ultrasonication Assisted α‐Arylation of N‐heteroarenes Employing 1‐Aryltriazenes Promoted by Brønsted Acidic Ionic Liquid under Aerobic Conditions

AbstractAn efficient and facile methodology for the synthesis of α‐arylated N‐heteroarenes was developed under aerobic conditions by means of ultrasound assistance, as well as conventional heating via a direct α‐arylation protocol employing Imidazolium based ionic liquids serving as both acid promoter and solvent. Structurally diverse N‐heteroarenes and 1‐aryltriazenes were evaluated for this reaction. This methodology has successfully provided a synthetic handle for various electron‐rich and electron‐deficient arylated N‐heteroarenes under metal and/or peroxide free conditions in good to excellent yields. The total synthesis of the known oxoisoaporphine class of alkaloids Menisporphine &amp; Daurioxoisoporphine C was successfully accomplished using the current methodology as a key step in the total synthesis.

Foreign body removal with the assistance of ultrasound guidance and methylene blue staining in children-a cohort study.

Soft tissue foreign bodies (FBs) are very commonly observed in paediatric emergency departments. Not all FBs can be removed effectively, even via open surgery and image intensifier guidance. In the current study, we evaluated the efficiency of FB removal with the assistance of ultrasound (US) and methylene blue (MB) staining. We enrolled 80 patients at our clinical center between May 2016 and December 2020. Eleven patients were operated upon with the assistance of US guidance and MB and were defined as group A; the other 69 patients were defined as group B. For the patients in group A, US was first used to locate the FB; MB was then injected next to the FB. Open surgery was subsequently performed. For group B, the FBs were removed by conventional methods. The surgical outcomes were evaluated according to surgical duration, incision infection rates, radiograph exposure times, and FB residue rates. The average surgery time for group A was 0.35 ± 0.10hours; the corresponding time was 0.49 ± 0.50hours in group B and there was a significant difference between the groups (p = 0.032). The radiograph exposure times were 1.33 ± 0.34 in group A and 4.65 ± 1.81 times in group B (p = 0.021). This study demonstrates that assistance of US and MB staining is a more efficient approach compared with traditional methods for FB removal, and this surgical method can be used effectively for FB removal in children.

Ultrasound assisted approach for the desulfurization of model fuel using ionic liquid anchored carbon obtained from Prosopis juliflora

Carbon from the wood of Prosopis juliflora tree was oxidized and blended with minimal amount of activated charcoal and modified using trioctylmethylammonium chloride (Ionic liquid) for adsorptive removal of sulfur from the model fuel oil, Dibenzothiophene (DBT) in n-hexane. The oxidative desulfurization was performed by ultrasonication and the mechanism was ascertained by characterization of adsorbent material before and after adsorption using characterization techniques such as UV, FT-IR, SEM-EDX, XRD, XRF, XPS and TGA respectively. The porous morphology and specific surface area of the adsorbent was characterized using BET-N2 isotherm and the material was found to be mesoporous with specific area of 104.86 m2 g−1. The removal efficiency of 100 mg L−1 Dibenzothiophene under oxidized condition with 0.3 g of adsorbent dosage and ultrasound assistance for 60 min was found to be 99%. From the isotherm studies, kinetic models and thermodynamic parameters it was found that the adsorption process is endothermically favourable following pseudo-second-order kinetics. The regeneration of the carbonaceous adsorbent was achieved using n-pentane as the solvent.

Arthroscopic removal of osteochondral fragments located within the condylar fossa of the third metacarpus/metatarsus in Thoroughbred yearlings.

To describe an arthroscopic technique for the removal of osteochondral fragments located within the condylar fossa of the third metacarpal/tarsal bone. Retrospective study. Thoroughbred yearlings (n=11). Osteochondral fragments located within the condylar fossa of the third metacarpal/tarsal bone identified during presale radiographic examination were removed via arthroscopy, assisted with ultrasonography in select cases. Complete fragment removal was confirmed by intraoperative radiography. Fragments were successfully removed using rongeurs following dissection of soft tissue attachments using a bipolar radiofrequency probe. No postoperative complications occurred. An ipsilateral arthroscopic and instrument portal coupled with ultrasound assistance and a radiofrequency probe allowed for successful removal of fragments located within the condylar fossa of the third metacarpal/tarsal bone. The technique allowed for the removal of the unstable osteochondral fragment and associated physical debris. The described surgical technique enables the removal of osteochondral fragments located within the condylar fossa of the third metacarpal/tarsal bone with minimal disruption to the surrounding soft tissues.

Techniques to Improve Peripheral Intravenous Catheter Placement

Techniques to Improve Peripheral Intravenous Catheter Placement

Mass transfer enhancement of tuna brining with different NaCl concentrations assisted by ultrasound

The influence of different NaCl concentrations (2.5, 5, 7.5 and 10% (w/w)) on the mass transfer kinetics of tuna during brining process with and without ultrasound assistance was evaluated. Results showed that an increase in NaCl concentration and the application of ultrasound accelerated the salt diffusion in the tuna muscle, and the highest yield was obtained in 5% brine concentration. Moreover, the kinetics parameters were significantly affected by the NaCl concentration and ultrasound application during brining. The values of the mass transfer kinetics parameters (k1, k2) for total and water weight changes decreased as NaCl concentration increased with and without ultrasound assistance during brining. In contrast, the higher the NaCl concentration, the higher the value of the salting kinetics parameters for salt weight changes. The application of ultrasound enhanced the salt effective diffusion coefficient (De) from 402.8% to 653.21% during the brining process, and the highest De was also found at 5% brine concentration. The application of ultrasound can improve the uniformity of salt distribution, enhance water holding capacity, reduce hardness and chewiness, but have no significant effect on color of tuna muscle.

Evaluation of crossing-linking sites of egg white protein–polyphenol conjugates: Fabricated using a conventional and ultrasound-assisted free radical technique

There has been strong interest in developing effective strategies to inhibit lipid oxidation in emulsified food products such as ω-3 fatty acids, carotenoids, or carotenoids. Dual-functional protein emulsifiers with antioxidant and emulsifying properties are in the spotlight. Our aim was to investigate the influence of caffeic acid (CF), chlorogenic acid (CA) with a C3-C6 structure, epigallocatechin gallate (EGCG), catechin (CT), and quercetin (QE) with a C6-C3-C6 structure on the cross-linking sites and structure of egg white protein (EWP)–polyphenol conjugates fabricated by the free radical method under conventional water bath (WB) and ultrasound assisted (US) conditions. Results of structural analysis and liquid chromatography–tandem mass spectrometry indicated that the structure of EWP–polyphenol conjugates and the cross-linking sites of the two are influenced by the polyphenol structure and the free radical system. Our study provides important information about the mechanism of research into proteins and polyphenols using the free radical method.

Gaseous Arsenic Capture in Flue Gas by CuCl2-Modified Halloysite Nanotube Composites with High-Temperature NOx and SOx Resistance.

Gaseous arsenic emitted from coal combustion flue gas (CCFG) causes not only severe contamination of the environment but also the failure of selective catalytic reduction (SCR) catalysts in power plants. Development of inexpensive and effective adsorbents or techniques for the removal of arsenic from high-temperature CCFG is crucial. In this study, halloysite nanotubes (HNTs) at low price were modified with CuCl2 (CuCl2-HNTs) through ultrasound assistance and applied for capturing As2O3(g) in simulated flue gas (SFG). Experiments on arsenic adsorption performance, adsorption mechanism, and adsorption energy based on density functional theory were performed. Modification with CuCl2 clearly enhanced the arsenic uptake capacity (approximately 12.3 mg/g) at 600 °C for SFG. The adsorbent exhibited favorable tolerance to high concentrations of NOx and SOx. The As2O3(III) was oxidized and transformed into As2O5(V) on the CuCl2-HNTs. The Al-O bridge had the highest adsorption energy for the O end of the As-O group (-2.986 eV), and the combination formed between arsenic-containing groups and aluminum was stable. In addition, the captured arsenic could be stabilized in the sorbent at high temperature, making it possible to use the sorbent before the SCR system. This demonstrates that CuCl2-HNTs is a promising sorbent for arsenic oxidation and removal from CCFG.

Natural Orifice Endosonographic Colposuspension With Rectopexy for Combined Pelvic Organ Prolapse: A Feasibility Study.

We describe a natural orifice technique for simultaneous endoluminal lateral suspension of apical vaginal wall and rectal prolapse fixation with ultrasound and fluoroscopic assistance. The technique is minimally invasive, can be performed under regional anaesthesia, and avoids laparotomy or use of a mesh in addition to preserving the uterus. This technique involves suprapubic transvaginal ventral suture colposuspension, fixation of the anterior rectal wall to the undersurface of the anterior abdominal wall and tack fixation of the posterior rectal wall to the underlying sacral promontory through a submucosal tunnel performed endoscopically with fluoroscopic and ultrasound assistance. Seven patients with a mean age of 63 years were followed between 3 to 11 months. This is a novel minimally invasive transluminal procedure that repairs concomitant rectal and vaginal prolapse in the same sitting. Improvement in the instrument design and incorporation of endoluminal robotic systems will enhance the technical ease. The study needs validation in larger series of patients with longer follow-up.

Effect of Ultrasound-Assisted, Microwave-Assisted and Ultrasound-Microwave-Assisted Extraction on Pectin Extraction from Industrial Tomato Waste

This work aimed to study the effect of ultrasound-assisted (UAE), microwave-assisted (MAE), and ultrasound-microwave-assisted (UMAE) methods for pectin extraction from industrial tomato waste. The overall performance index from the fuzzy analytical method with three criteria, pectin yield, galacturonic acid, and lycopene content, was applied to evaluate the best extraction conditions by using the weight of 75, 20, and 5, respectively. The UAE conditions was performed at a temperature of 80 °C for 20 min with the variations in the extraction pH and the solid liquid (SL) ratio. The best UAE conditions with high pectin yield, and high total carboxyl group, as well as a lycopene content, was the pH of 1.5 and the SL ratio of 1:30. The MAE conditions was performed with variations in the microwave powers and times. The results showed that the best MAE conditions were 300 W for 10 min, which gave high pectin yield with high galacturonic acid and lycopene content. Various conditions of UMAE at the best conditions of MAE and UAE were performed and exhibited that the UAE had more positively affected the pectin yield. However, the FTIR spectra of obtained pectins from different extraction techniques showed a similar pectin structure.

A modeling strategy for hot drying of rough rice assisted by ultrasonic wave

Current research studies the possibility of moderating convective drying of a packed bed of rough rice with ultrasound assistance at 21 kHz frequency. In this regard, a convective dryer equipped with an ultrasound generator was utilized to operate at an air temperature of 35–55 °C, velocity of 0.2–1.4 m s−1, and ultrasound power of 30−150 W for a bed thickness of 20 cm. For mathematical modeling of drying kinetics, the basic equations of mass and enthalpy conservation were implemented over an arbitrary control volume and solved by the finite difference method. The degradation kinetics of vitamin B3 concentration of the packed bed was also modeled using an empirical first-order kinetics model. Modeling results of the drying kinetics with (R2 of 0.9569−0.9889, RMSE of 0.014−0.073, and RCV of 3.341–6.378%) and without (R2 of 0.9402−0.9980, RMSE of 0.006−0.083, and RCV of 1.084–7.740%) sonication were coherent with the observed drying kinetics. The developed kinetic model for bioactivity could also estimate the time evolution of vitamin B3 concentration of the dried product, acceptably. The key results revealed the noticeable effect of sonication on maintaining vitamin B3 concentration. The loss pattern of the forecasted vitamin B3 concentration within the bed was linear and diminished by the external action of ultrasound vibration during drying in lower air temperatures and high power levels.

Hundred years of transperineal prostate biopsy.

The earliest recorded efforts to biopsy prostate, in the early 20th century, were made through transperineal (TP) approach, with open perineal prostate biopsy (PBx) being considered the gold standard for prostate cancer (PCa) diagnosis in that era. Later, to minimize morbidity and increase diagnostic accuracy, several technical modifications and transrectal ultrasound (TRUS) assistance were incorporated. However, in the 1980s, the transrectal (TR) approach became the predominant PBx method following the introduction of TRUS-TR PBx with sextant sampling, providing a convenient and efficacious method for prostate sampling. With modernization of PCa diagnosis, a recent resurgence of the TP PBx has been observed, driven primarily by TR drawbacks of infectious complications and sampling limitations. TP PBx is rapidly emerging as the new PBx standard, being officially recommended as the initial approach for biopsy in Europe and is increasingly being conducted and studied in the United States. The modern era of TP PBx is based on the improvements in local anesthesia techniques, TP access systems, and robotic assistance. These modifications and advancements have improved the ease of use, patient comfort, and diagnostic outcomes with TP PBx. Herein, we present a history of the evolution of TP PBx spanning over 100 years and explore the basis of the technique that merits future utilization.

BLUEBERRY, SEA BUCKTHORN FRUITS AND APPLE BEVERAGE: BIOCHEMICAL AND SENSORIAL CHARACTERIZATION

This work aimed at optimizing the extraction of total phenolic (TP) and total monomeric anthocyanin (TMA) content for the development of a potentially functional wild blueberry smoothie (BP) with apple puree (AP), apple juice (AJ) and sea buckthorn puree (SBJ) in various proportions using conventional extraction (CE) and advanced extraction techniques [ultrasound-assisted (UAE)]. There were also analyzed the rheological behavior and the color attributes (lightness and redness respectively) of smoothie samples. S7 smoothie sample [30 AP/30 AJ/20 SBJ/20 BP (UAE)] provided a beverage with significant higher amount (21.40%) of anthocyanins (TMA) compared to sample S10 [30 AP/30 AJ/20 SBJ/20 BP (CE)] in which the extraction of anthocyanins was by the classical method. Further, different color attributes, particularly brightness (L *), redness (a *) and yellow (b *) decreased considerably for the samples with 15 and 20% addition of blueberry puree. Therefore, ultrasound-assisted extraction had a significant effect on the amount of anthocyanins extracted, compared to the classical extraction method.

Practical insights into ultrasound-assisted heterogeneous Fenton membrane reactors for water treatment

Cavitation damage to membranes is a major barrier for developing an ultrasound (US)-assisted membrane water treatment process. In this study, US was integrated to a heterogeneous Fenton membrane reactor for the treatment of pharmaceutical-containing water with the aims of i) fouling control, ii) enhancement of heterogeneous Fenton oxidation. In order to prevent membrane damages due to cavitation, the stable and violent cavitation regions were identified by quantification and analysis of the cavitation activity axial along the ultrasound transducer via hydrophone measurements. Results showed the cavitation activities occur in both regions with US on, while the cavitation damage to membrane materials was only observed when membranes were placed in the violent cavitation region. On one hand, cracking and physical erosion of the surface were observed on membrane samples when exposed to violent cavitation. On the other hand, no such erosion occurred in stable cavitation regions, and membranes kept their mechanical, chemical and morphological properties, confirming that cavitation damage was controlled by placing membranes in the identified stable cavitation region. Based on these results, a heterogeneous Sono-Fenton membrane reactor was designed by placing a scalable hollow-fibre membrane module in the stable cavitation region. Within this reactor, the experiments confirmed that the oxidation of organics was enhanced thanks to the US assistance in the novel designed heterogeneous Sono-Fenton membrane reactor. However, this study also showed that US accelerated membrane ageing and zeolite-catalysts erosion, leading to more severe fouling. Overall, this paper introduces a method to control the cavitation damage to membranes and discusses the issues in US-assisted membrane systems with practical insights.