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Ultrasound-accelerated hydrolysis is effectively used for the first time in the release of 3-monochloropropane-1,2-diol (3-MCPD) from its fatty esters. Indirect determination of 3-MCPDE fatty acid esters was performed under alkaline and acid conditions using sodium methoxide and sulfuric acid, respectively, prior to GC-MS analysis. Dispersive liquid-liquid microextraction (DLLME) was used to derivatize the free 3-MCPD with n-heptafluorobutyrylimidazole (HFBI). Two asymmetrical screening designs were used to evaluate parameters affecting the methods' performances: time, temperature, hydrolytic agent volume, and concentration. A comparative study between both methods was performed. Research showed that comparable results are achieved in terms of linearity (r2 > 0.9995), specificity, accuracy, and precision. Determination limits were lower for the alkaline method (67 ng g−1). Twenty samples of four types of edible oil were assessed using both methods: extra virgin olive oil (EVO), refined sunflower oil, refined olive oil, and palm oil. Results obtained here were comparable and similar to those reported in the literature. Alkaline hydrolysis was the recommended approach and should be used in occurrence studies. • Two novel indirect approaches for 3-MCPD were developed and validated. • Acid and basic hydrolysis of 3-MCPD esters were ultrasound-accelerated. • HFBI derivatization is performed during DLLME prior GC-MS analysis. • 20 edible oil samples were analyzed for 3-MCPD presence. • Alkaline approach reduced consumption of reagents and time. [ABSTRACT FROM AUTHOR]

The poor interfacial properties and weavability of carbon fiber reinforced polymer (CFRP) composites stem from the surface chemical inertness and low wear resistance of carbon fiber (CF). Herein, we developed an effective approach to fabricate the CF@Polydimethylsiloxane/MXene (CF@PDMS/MXene) using ultrasound-assisted techniques, to improve both wear resistance and interfacial properties. The effectiveness of the modified treatment was assessed by Fourier transform infrared spectroscopy (FT-IR), microscopic confocal laser Raman spectrometer (Raman), X-ray photoelectron spectroscopy (XPS), and thermogravimetric analysis (TGA). The success of the graft was evaluated using field emission scanning electron microscopes (FE-SEM) and energy dispersive spectrometry (EDS). The interfacial shear strength (IFSS) of the composite was evaluated through fiber pull-out experiments. Different weight ratios of MXene nanoparticles were employed during the grafting process to investigate their impact on surface morphology, wear resistance, and interfacial properties. The results demonstrated that CF@PDMS/MXene-1.5 wt% exhibited a residual fracture tensile strength 14.8 % higher than desized CF when the MXene concentration was increased to 1.5 wt%. Additionally, the IFSS of CF@PDMS/MXene-1.5 wt% was observed to be 113 % greater than desized CF. Consequently, this novel modification strategy holds great promise for enhancing the mechanical performance of CFRP composites. [ABSTRACT FROM AUTHOR]

[Display omitted] • Thermodynamic and parameters for selective alkaline leaching of Sn are studied. • Ultrasound can observably facilitate the alkaline leaching of Sn from tinplate scraps. • Microstructure, kinetics and electrochemistry differences in leaching are investigated. • Novel acoustoelectric synergy is applied to clarify tin intensifying dissolution mechanism. Clean and fast extraction of tin from the surface of tinplate scraps is of great significance for the efficient utilization of waste resources. However, the dense tin layer causes the low efficiency of conventional leaching process. To improve Sn leaching efficiency, the ultrasound technique was adopted to extract Sn from tinplate scraps by alkaline leaching in this study. In the NaOH-H 2 O 2 leaching system, metallic tin and alloyed tin in Fe-Sn alloy located on the surface of tinplate scraps can be oxidized and transferred to soluble Na 2 SnO 3 , while the iron in Fe-Sn alloy was oxidized to oxides which were chemically inert in alkaline solution. The differences in chemical solubility of Sn and Fe, and solubleness of stannate and iron oxides gave rise to the selective separation of Sn from the tinplate scraps. The effects of the leaching parameters on the Sn leaching behaviors in conventional and ultrasound-assisted leaching processes were compared. The conventional leaching temperature and time were significantly reduced during the ultrasound-assisted leaching process. Almost all of Sn can be extracted after conventional leaching at 1 mol/L NaOH, temperature of 80 ℃ and time of 60 min, however the same Sn leaching effect can be achieved by ultrasound-assisted leaching at 60 ℃ for 30 min with ultrasound power of 60% (360 W). Sn leaching kinetics based on the plate model demonstrated the reaction rate constant of the ultrasound-assisted leaching was 70% higher than that of the conventional leaching. A novel acoustoelectric synergy effect underlying intensifying mechanism by ultrasound irradiation was proposed in this study. Eventually, this work provided a rapid and clean tin extraction method from tinplate scraps via the ultrasound-assisted alkaline leaching treatment. [ABSTRACT FROM AUTHOR]

In order to extract antioxidant phenolic compounds from spent grain (SG) two extraction methods were studied: the ultrasound-assisted method (US) and the Ultra-Turrax method (high stirring rate) (UT). Liquid to solid ratios, solvent concentration, time, and temperature/stirring rate were optimized. Spent grain extracts were analyzed for their total phenol content (TPC) (0.62 to 1.76 mg GAE/g SG DW for Ultra-Turrax pretreatment, and 0.57 to 2.11 mg GAE/g SG DW for ultrasound-assisted pretreatment), total flavonoid content (TFC) (0.6 to 1.67 mg QE/g SG DW for UT, and 0.5 to 1.63 mg QE/g SG DW for US), and antioxidant activity was measured using 2,2-diphenyl-2-picrylhydrazyl (DPPH) free radical (25.88% to 79.58% for UT, and 27.49% to 78.30% for UT). TPC was greater at a high stirring rate and high exposure time up to a certain extent for the Ultra-Turrax method, and at a high temperature for the ultrasound-assisted method. P-coumaric acid (20.4 ± 1.72 mg/100 SG DW for UT, and 14.0 ± 1.14 mg/100 SG DW for US) accounted for the majority of the phenolic found compounds, followed by rosmarinic (6.5 ± 0.96 mg/100 SG DW for UT, and 4.0 ± 0.76 mg/100 SG DW for US), chlorogenic (5.4 ± 1.1 mg/100 SG DW for UT, and non-detectable for US), and vanillic acids (3.1 ± 0.8 mg/100 SG DW for UT, and 10.0 ± 1.03 mg/100 SG DW for US) were found in lower quantities. Protocatechuic (0.7 ± 0.05 mg/100 SG DW for UT, and non-detectable for US), 4-hydroxy benzoic (1.1 ± 0.06 mg/100 SG DW for UT, and non-detectable for US), and caffeic acids (0.7 ± 0.03 mg/100 SG DW for UT, and non-detectable for US) were present in very small amounts. Ultrasound-assisted and Ultra-Turrax pretreatments were demonstrated to be efficient methods to recover these value-added compounds.

The freshwater mussel protein was hydrolysed using ultrasound-assisted enzymolysis. Ultrasound-assisted freshwater mussel protein hydrolysates (UPH) were divided into four fractions (> 10, 6-10, 3-6, and < 3 kDa) using ultrafiltration, and the fraction with the highest antioxidant activity was further subdivided into four fractions (F1-F4) using gel chromatography. The amino acid compositions and antioxidant activities (DPPH, hydroxyl and superoxide radical scavenging activities, reducing power, ferrous ion chelating activity, and inhibition of linoleic acid oxidation) of peptide fractions were investigated. The results showed that the antioxidant activity of the < 3 kDa fraction was significantly higher than that of UPH, > 10, 6-10, and 3-6 kDa fractions. The antioxidant activity of F2 was again higher compared with the < 3 kDa fraction and higher than that of F1, F3, and F4. Amino acid analysis showed that the antioxidant activities (except for chelating activity) of peptides increased with increasing hydrophobic amino acid content. The < 3 kDa and F2 fractions exhibited strong inhibition of linoleic acid oxidation, their effects being even better than that of ascorbic acid (Vc) and l-glutathione (GSH). Therefore, these peptide fractions from freshwater mussel may be a potential natural antioxidant that could be added to various foods.

Thiazines are a sizable class of organic heterocycles that are notable for their skeletal versatility and relative chemical simplicity, making them among the most flexible sources of biologically active compounds. The term "green synthesis" refers to implementing energy-efficient procedures for the nature-friendly production of materials and chemicals using green solvents, catalysts, and suitable reaction conditions. Considering the importance of green chemistry and the outstanding therapeutic profile of thiazines, the present work was designed to review the recent advances in green chemistry-based synthetic strategies of thiazine and its derivatives. The green synthetic approaches, including microwave-assisted, ultrasound-assisted, and various other synthetic methods for thiazine and its derivatives, were discussed and generalized. In addition, applications of thiazine and its derivatives in pharmaceutical sciences were explained with examples of marketed drugs.The discussed sustainable synthetic methods for thiazines and their derivatives could be useful in developing other medicinally important lead molecules. They could also aid in developing new synthetic schemes and apparatuses that may simplify chemical manufacturing processes and enable novel reactions with minimal by-products while questing for optimal, green solvents. This review can help anyone interested in this fascinating class of heterocycles to make decisions about selecting targets and tasks for future research., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Summary: The effects of osmotic (OP), ultrasound‐assisted osmotic pretreatment (UAOP) and frying conditions on quality and storage stability of vacuum fried pumpkin chips were investigated. The pumpkin samples were pretreated in maltodextrin solution and subsequently fried at different temperatures (90–110 °C) and time periods (10–30 min). The results demonstrated that the moisture content, water activity, lightness, yellowness and carotenoid content of the fried chips decreased, while oil content, hardness and a* (dark brown colour) value increased with increasing frying temperature and time. UAOP reduced about 16.0% of oil absorption and enhanced approximately 70% of carotenoid retention in the fried chips. UAOP samples were also more stable during storage than the untreated ones, indicated by lower degradation kinetics constants of key quality parameters. The proposed pretreatment could be an effective method for food industries to develop vacuum fried pumpkin chips with improved quality and stability. [ABSTRACT FROM AUTHOR]

Brewer's spent grain (BSG) is a residue produced in large amounts by the brewing industry and may be used in bioprocesses as a source of sugar due to its chemical composition. The objectives of this work were to determine the chemical composition of BSG and to investigate its potential in obtaining fermentable sugars through enzymatic hydrolysis. For this purpose, mechanical stirring, direct and indirect ultrasound processes were studied to evaluate the efficiency of BSG enzymatic hydrolysis. Operational variables of mechanical stirring (temperature, enzyme and substrate concentrations) and ultrasound (pulse factor and amplitude) systems were analyzed. The highest sugar yield was 370.9 g kg−1 using direct sonication system at a pulse factor of 0.23 and oscillation amplitude of 50%. Sugar yield in direct ultrasound system was 2.6 and 4.9 times greater than indirect sonication and mechanical stirring systems, respectively. For BSG hydrolysis using enzymes, direct sonication presented better results than mechanical stirring and indirect sonication processes. Besides, the treatment time using direct sonication was diminished, confirming that it is a promising technology for improving the yields of fermentable sugars from BSG. [ABSTRACT FROM AUTHOR]

This study proposes a welding process, ultrasound-assisted friction stir welding of dissimilar Al/Cu metals. Zinc foil is melted using the heat generated by a pinless stirring tool, and the molten intermediate layer is stirred by ultrasonic cavitation to achieve an effective connection. The metallurgical reaction behavior of the joint under the action of the sound field was studied, and the effects of different microstructures on the joint performance were analyzed. Specifically, the following observations were reported in this study: (1) When ultrasound assistance was used, the cavitation effect changed the brittle intermetallic compounds of Al2Cu from a continuous distribution to a block distribution, and the mechanical properties of the joint were greatly improved; (2) the effects of the thickness of the zinc were also determined. The results showed that the highest shear tensile force was obtained when the thickness of the zinc foil was 0.2 mm. When the thickness was 0.3 mm, the ultrasound effect was weakened. The copper-side interface generated a zigzag-shaped Al4.2Cu3.2Zn0.7 layer with a thickness of 3.4 μm and had a continuous distribution. Increasing the thickness of the zinc to 0.5 mm, however, drastically decreased the mechanical properties of the joint due to incomplete melting of the zinc layer. [ABSTRACT FROM AUTHOR]

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study aimed to determine optimal extraction parameters by using response surface methodology, examining the effect of microencapsulation on crocin retention, and evaluating the temperature and pH stability of crocin microcapsules. The effect of process variables on the crocin yield was successfully determined by quadratic models (R2 > 0.99 and adj R2 > 0.98). All variables significantly affected the crocin yield (P < 0.1). The process parameters, namely extraction time (4.40 min), temperature (55 °C), amplitude level (94%), and liquid to solid ratio (L/S) (1000) were determined as optimum extraction points. Safranal was shown to be a compound with major volatility in both the saffron and microcapsule extracts. Safranal, 2,4,4-trimethyl-3-carboxaldehyde-5-hydroxy-2,5-cyclohexadiene-1-one, 4-hydroxy-2,6,6-trimethyl-1-cyclohexene-1-carboxaldehyde (HTCC), and isophorone were other major volatile compounds of saffron extract. The encapsulation process affected volatile percentage distribution insignificantly (P > 0.05). The thermal and pH stability of the crocin was determined at different temperatures (60, 70, 80, and 90 °C) and pH levels (2, 4.5, and 6). The crocin degradation showed first order kinetic, and degradation rate constant (k) were significantly affected by pH and temperature (P < 0.05). A high temperature and low pH showed higher degradation (k) in crocin content. This study suggested that crocin from saffron stigmas should be preserved by spray drying encapsulation and should only be used as a natural food colorant in low or moderate acid food. [ABSTRACT FROM AUTHOR]

Anthocyanin is widely used in the food industry as a substitute of red synthetic food colouring. Anthocyanins and their derivatives have been listed in the Codex Alimentarius Commission in the European Union as a natural colouring agent with the code E163. Roselle (Hibiscus sabdariffa L.) is considered as a readily available natural source for anthocyanin since it is ubiquitous in Indonesia. Various extraction methods such as maceration, ultrasonic-assisted extraction and microwave-assisted extraction have been applied to extract anthocyanin. In the present work, both maceration (ME) and ultrasound-assisted (UAE) techniques were compared in assessing the extraction performance of two varieties of roselle (red and purple). The effect of solvent types and solute to solvent ratios were also evaluated. The liquid extract was further encapsulated and characterised. The present work demonstrated that UAE was better when compared to ME. Moreover, the purple roselle calyces produced more anthocyanin content than the red calyces. In addition, it was found that water was a better choice of solvent as compared to ethanol. Anthocyanin powder from roselle calyces has average particle size of 4.241 μm and 3.942 μm. The characterisation of anthocyanin powder resulted in the moisture content of 10.29% and 9.67% and solubility of 96.92% and 97.44% for red and purple roselle, respectively. The colour intensity based on chromameter confirmed that the anthocyanin powder having L*, a* and b* values around 42.61-43.91, 24.40-24.79 and 5.56 -7.35, respectively. [ABSTRACT FROM AUTHOR]

BACKGROUND: Ultrasound‐assisted fractionation of DDGS under mild conditions was proposed for extracting xylan from dried distillers' grains with solubles (DDGS) and recovering protein‐rich DDGS residue as animal feed. The composition and properties of xylan fractions and the DDGS residue obtained by ultrasound‐assisted extraction and those by a conventional method of alkaline extraction without ultrasound‐assistance were compared. RESULTS: Compared with the result for the conventional method, a similar xylan yield of 73.8% in the extracted liquid, but higher protein content of 26.2% in the DDGS residue were obtained by the ultrasound‐assisted process with NaOH at ultrasound power of 900W and 30 °C for 20 min. The ultrasound‐assisted process has a significant impact on the sugar composition and polysaccharide side chain and polymerization degree of the xylan fractions. The DDGS residue produced by the ultrasound‐assisted process had a fine porous structure as well as greater protein and essential amino acid content. The enzymatic hydrolysis of cellulose in DDGS residue reached 70% in the initial 3 h. CONCLUSION: Ultrasound‐assisted fractionation was an efficient process for comprehensive utilization of xylan and protein in the DDGS. The xylan fractions with lower polymerization degree were perfect feedstock for xylooligosaccharide production by enzymatic hydrolysis. The DDGS residue with adequate nutrition composition and efficient digestibility had potential advantages as an alternative animal feed to DDGS. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

In this study, the collagen-g-poly(acrylic acid-co-N-vinylpyrrolidone)/Fe3O4@SiO2 (collagen-g-p(AA-co-NVP)/Fe3O4@SiO2) as magnetic nanocomposite hydrogel was synthesized by graft copolymerization of acrylic acid (AA) and N-vinylpyrrolidone (NVP) onto collagen in the presence of the Fe3O4@SiO2 using ammonium persulfate as a free radical initiator and bis[2-(methacryloyloxy)ethyl] phosphate as a crosslinker under ultrasound-assisted condition. The blank collagen-g-p(AA-co-NVP) hydrogel and its composite with the Fe3O4@SiO2 nanoparticles were characterized by means of FTIR, SEM-EDS, XRD, VSM and TGA methods. The effects of different parameters such as pH, dose of adsorbent and time on swelling behavior were examined. The swelling ratio of the collagen-g-p(AA-co-NVP) hydrogel increased in the presence of the Fe3O4@SiO2 nanoparticles. Adsorption behavior of magnetic nanocomposite hydrogel was investigated for the adsorption of dyes and it was found to remove about 93% for methylene blue, 96% for brilliant green and 89% for rhodamine B in 50 mg/L of dyes solutions at pH 7. Kinetic study revealed the applicability of pseudo-first-order and pseudo-second-order models for the adsorption of mentioned dyes. The adsorption isotherm was studied in 25, 35, 45 and 55 °C using Langmuir, Freundlich, Temkin and Sips models and the adsorption data were well described by Langmuir isotherm model. Negative values of ΔGº for all three dyes suggested the feasibility of dyes removal and support for spontaneous adsorption of mentioned dyes on magnetic nanocomposite hydrogel. Desorption of dyes from the dye loaded nanocomposite hydrogel was simply done in ethanol. The results indicate that the prepared magnetic nanocomposite hydrogel is an efficient adsorbent with high adsorption capacity for the aforementioned dyes. [ABSTRACT FROM AUTHOR]

Unburnt coal in a boiler gets converted to fly ash and bottom ash. Fly ash particles travel along with flue gas and get deposited on heat transfer surfaces along the way. Fouling and slagging are phenomena associated with fly ash deposits which could potentially damage the heat transfer surface, if left unattended. Sodium and potassium are directly linked to the deposition of fly ash, as they form a molten salt film which aids in sticking of fly ash particles. Ultrasound is one of the mitigation techniques used to prevent ash deposition. This study aims at reducing the concentrations of alkali metals in coal as a pretreatment method, using ultrasound. Two modes of operation are chosen: continuous and pulsed. A solvent has been used to enhance the leaching process. In the pulsed mode, the sample is alternated between periods of exposure and nonexposure. A maximum leaching rate of 62% for potassium and 24.5% for sodium was observed in the continuous mode at 360 kHz of operation while pulsed mode of operation showed a maximum leaching rate of 91.3% and 54.4% for potassium and sodium operated at 360 kHz, respectively. The experimental data have been fit to the shrinking core model, and the rate-controlling step has been found to be surface diffusion of reactants into the core. The effect of various parameters is analyzed and compared for pulsed and continuous modes of operation. Order of the reaction, activation energy, and leaching kinetics are obtained by fitting the data into the shrinking core model. [ABSTRACT FROM AUTHOR]

Recovering silicon from hazardous solar grade silicon (SoG-Si) cutting slurry waste generated in silicon wafer production is of great significance, but it is distinctly important to remove iron first. Dilute sulfuric acid with assistance of ultrasound was used to remove iron from SoG-Si cutting slurry waste in this study. The occurrence state of iron in the SoG-Si cutting slurry waste were analyzed. Effects of ultrasound power, ultrasound frequency, liquid-solid ratio, acid concentration and reaction temperature on the iron leaching ratio were studied. Conventional leaching (CL) and ultrasound-assisted leaching (UAL) were compared by the leaching ratio, XRD, particle sizes and morphologies. It showed that ultrasound could disintegrate aggregations and disperse aggregated particles more efficiently than CL, and accelerate leaching ratio about 7.84%, and shorten leaching time as much as 50% at 70∘. Kinetics analysis showed that CL reaction follows classical shrinking core model and rate-controlling step is chemical reaction. However, the UAL reaction follows shrinking unreacted core model and rate-controlling step is chemical reaction within 20 min and converts to internal diffusion after 20 min. After leaching leached residues can be considered as precious silicon source for solar cells, and filtered leaching solutions were fully recycled. [ABSTRACT FROM AUTHOR]

Abstract Ultrasound and water soluble soybean polysaccharide (SSPS) were applied during the freezing of grass carp surimi. Ultrasound-assisted immersion freezing (UF) process was observed from 0 °C to −15 °C. Based on characteristic freezing time, tempering-stage freezing rate and the quality change of surimi after a 14-day storage period, the optimal sonication was performed 5 times at 300 W, for 10 s, with 40 s intervals. The cryoprotective effects of SSPS content on surimi myofibillar protein were subsequently investigated during 28-day frozen storage at −18 °C. The Ca2+-ATPase activity, total sulphydryl content, active sulphydryl content, salt extractable protein content, whiteness and water-holding capacity of frozen surimi were determined after adding SSPS (0%, 1%, 3% and 5%). The results showed that synergism of SSPS and UF occurred. Consequently 3% SSPS was best for mitigating the protein denaturation during processing. Highlights • Ultrasound could significantly increase the freezing rates of grass carp surimi. • Water soluble soybean polysaccharide (SSPS) could mitigate the protein denaturation. • SSPS was demonstrated as a novel cryoprotectant for grass carp surimi. • A new method of SSPS-ultrasound-assisted immersion freezing was investigated. [ABSTRACT FROM AUTHOR]

Abstract Salvia miltiorrhiza has been widely used in Asia for medicinal purposes for >1000 years due to the high levels of bioactive constituents it contains. In this study, a simple and rapid ultrasound-assisted liquid extraction (5 min) was applied for the extraction of these bioactive constituents. The extracts were analyzed by using rapid ultrahigh performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) with simultaneous positive and negative electrospray ionization in a single analytical run. Eight analytes were separated within 2.2 min during 6 min of run time with UHPLC-MS/MS operated in multiple reaction monitoring (MRM) mode. The concentration of salvianolic acids and tanshinones in the different organs of different varieties of Salvia miltiorrhiza ranged from 6.4 to 382.1 mg/g and 0.03 to 31.7 mg/g, respectively. To the best of our knowledge, this is the first report to characterize the tanshinone compounds found in the flower and stem/leaf of Salvia miltiorrhiza by UHPLC-MS/MS. Highlights • First report of tanshinones were found in leaf and flower from Salvia Miltiorrhiza. • A simple and rapid ultrasound-assisted liquid extraction was developed. • High throughput screening method by UPLC-MS/MS operated in MRM mode. • Salvianolic acid and tanshinones were quantified within 2.2 min in 6 min run time. [ABSTRACT FROM AUTHOR]

Graphical abstract A facile one-pot and four-component synthesis of benzo[1,3]thiazine derivatives via intramolecular C H activation reaction from isocyanides, aniline and benzoyl (acetyl) isothiocyanate adduct catalyzed by copper (I) iodide in acetone at 30 °C is described. Highlights • Novel synthesis of highly functionalized benzo[1,3]thiazine. • Intramolecular C H activation reactions of isocyanides, aniline-benzoyl(acetyl) isothiocyanate adduct. • Use of sonochemical methodology as an efficient method in reduction the reaction time for the synthesis of compound. • CuI catalyzed the efficient synthesis of benzo[1,3]thiazine. Abstract A facile sonochemical route for the synthesis of benzo[1,3]thiazine derivatives via a one pot, multicomponent, intramolecular C H activation reaction from isocyanides, aniline and benzoyl (acetyl) isothiocyanate adduct catalyzed by copper (I) iodide in acetone at 30 °C have been reported. The advantages of the described method include using simple and readily available starting materials and performing under mild copper-catalytic reaction conditions and also obtaining pure product with high yield without applying column chromatography. Furthermore, using the sonochemical methodology as an efficient method led to reduce the reaction times. [ABSTRACT FROM AUTHOR]

Highlights • Leaching silver without oxygen and ammonia to be achieved by ultrasonic field. • Ultrasonic enhanced leaching mechanism has a detailed analysis. • The dynamic models were analyzed in detail separately. Abstract The process to fast recovery of silver from the spent symbiosis lead-zinc mine enhanced by ultrasound has been developed. A system composed of thiosulfate and the spent symbiosis lead-zinc mine under ultrasound radiation is researched and compared with regular methods to prove the superiority of ultrasound enhanced leaching. Oxygen is not provided by the usual way but by the cavitation of ultrasound, and the effect of ultrasonic enhanced leaching is more obvious than oxygen enhanced leaching effect. We are more authoritative by combining some valuable literature after conducting systematic experiments. The process mechanism was analyzed by fire assaying, XRD, XRF, SEM and EDS. The optimal conditions were found out through single factor experiments: stirring rate of 300 rpm, thiosulfate concentration of 75 g/L, leaching temperature of 303 K, PH of 5, leaching time of 2 h and the ultrasound power of 100 W. And the leaching rate is 77.34% under the best conditions. When the ultrasonic experiment has the same parameters as the normal, the leaching rate at five minutes under ultrasonic conditions was 73.88%, while the leaching rate was only 72.51% at two hours under normal conditions. The apparent activation energy under conventional and ultrasonic conditions is 12.47 kJ/mol and 12.35 kJ/mol, respectively, and it is proved that both are controlled by diffusion. [ABSTRACT FROM AUTHOR]

At present in the world, the waste reverse osmosis membrane (WROM) after depth-fouled are enormous in quantity, this not only increases cost of ROM in use, causes the resource waste, but also bring on serious environmental problems. To realize performance recovery and recycling of WROM, a system that can monitor ultrasound-assisted chemical cleaning process was designed. Therewith, using the system, cleaning effects for WROM depth-fouled by transitional metal oxides and silica as well as a small amount of organic matters were evaluated under various circulating flow states of pure water, ultrasonic water or organic acids and compounded liquid. The research results manifested that, in 50 kHz of ultrasonic frequency and 0.64 W/cm2 of sound intensity, if only alone used tartaric acid, oxalic acid and citric acid to clean WROM, total defouling ratio for inorganic and organic pollutants could respectively reach about 70%, 83% and 85%, if adopted the mixing solution containing 6.9 g/L tartaric acid and 1.1 g/L Na4EDTA, the defouling ratio reached to 96% which was the best synergistic effect in cleaning. The obtained results in the research can be used in the industrial online cleaning for depth-fouled ROM or resuscitating for WROM in water treatment industries. [ABSTRACT FROM AUTHOR]

Quality parameters of açai juice processed with ultrasound-assisted, ozone and the combined methods were analyzed in this work. Two ultrasound energy densities (350 and 700 J·mL −1 ) and two ozonization times (5 and 10 min with 1.5 ppm) were analyzed for pure açai juice and 8 different treatments (2 2 complete factorial). To evaluate the quality parameters of the juice, physical-chemical analyzes such as pH, titratable acidity, cloud value, non-enzymatic browning, rheology, antioxidant activity (DPPH and ABTS), phenolic compounds, anthocyanins, enzymatic activity (peroxidase and polyphenol oxidase) and microbial counts (mesophilic bacteria, molds and yeasts) were conducted. The treatments with ozone were better for microbial inactivation and the ultrasound for enzymatic inactivation. In general, the use of non-thermal methods can be a good alternative for the processing of açai juice. [ABSTRACT FROM AUTHOR]

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Display omitted] • Considering their toxicity, the determination of PAEs in various sample is essential. • Green extraction strategy was developed and utilized for the extraction of PAEs in diapers. • The Box-Behnken model was used to evaluate the extraction condition. • The greenness of the developed extraction method was evaluated by application of GAPI tool. • The method is characterized by simplicity, rapidity and good accuracy. A green extraction strategy was developed and utilized for the extraction and determination of phthalates. The extraction is based on ultrasound-assisted extraction and a polypropylene porous membrane. The Box-Behnken model was performed to optimize the extraction condition. The optimal extraction conditions are 5.5 mL of ethyl acetate, 10 min of extraction time and 55 °C for extraction temperature. The developed green extraction method was successfully applied to extract target phthalate from baby's diapers. Under the optimal condition, the developed method provided acceptable recoveries in the range of 87 to 102% with a relative standard deviation lower than 13%. The developed method exhibited good linearity in the range of 0.05 to 10.0 µg g−1 with a coefficient of determination greater than 0.992 (R2). Applied the developed method coupled with the gas chromatography-mas spectroscopy (GC–MS) method, benzyl butyl phthalate (BBP) and dioctyl phthalate (DOP) were found in some diaper samples. While low concentrations of diisononyl phthalate (DINP) and diisodecyl phthalate (DIDP) were detected in almost all diaper samples. The greenness of the developed method was also evaluated. The developed method can be used as an alternative simple, green and efficient strategy for the determination of phthalates in baby diapers. In sum, the presented article is the first step in raising awareness about carcinogenic impurities to which infants and older children are exposed. [ABSTRACT FROM AUTHOR]

• Increasing the value of agricultural residue through ultrasonics. • Ultrasonic technology for pretreatment and valorization of biomass. • Unique characteristics of bioproducts obtained from agricultural residue. • Ultrasonics vs Conventional methods: Advantages and Disadvantages. • Potential to exploit ultrasonic technology for large-scale application. The utilization of agricultural residues to obtain biocompounds of high-added value has significantly increased in the past decades. The conversion of agro-based residues into valuable products appears to be an economically efficient, environment-friendly, and protracted waste management practice. The implementation of ultrasonic technologies in the conversion of value-added goods from agricultural waste materials through pre-treatment and valorization processes has imparted many advantageous effects including rapid processing, effective process performance, minimization of processing steps, minimal dependency on harmful chemicals, and an increased yield and properties of bio-products. To further enliven the literature and inspire new research investigations, this review covers the comprehensive work including theoretical principles, processes, and potential benefits of ultrasonic treatment technologies to assist the production of bio-products which emphasize the extraction yield and the characteristic of the end-product extracted from agriculture residues. A detailed evaluation of these methods and key aspects impacting their performance as well as the features and shortcomings of each ultrasound-assisted approach is also discussed. This review also addressed some of the challenges associated with using ultrasonic irradiation and proposed several potential techniques to maximize productivity. Understanding the concept of ultrasonication technique allow the academician and industrial practitioners to explore the possibility of applying a greener and sustainable approach of biomass extraction to be translated into higher scale production of commercial products. [ABSTRACT FROM AUTHOR]

[Display omitted] • An efficient ginseng residue oligosaccharide decolorization method was developed. • Three decolorization methods were systematically compared. • Ultrasound-assisted decolorization greatly shortened the decolorization time. • The GRO structure did not change significantly before and after decolorization. An efficient decolorization method for ginseng residue oligosaccharides (GROs) using ultrasound-assisted D392 macroporous resin was developed. The decolorization effects and color differences of activated carbon adsorption, hydrogen peroxide oxidation, and resin adsorption were evaluated. The optimal conditions of the three decolorization methods for static, dynamic, ultrasound-assisted resin adsorption were compared. The results showed that ultrasound-assisted decolorization had the best decolorization effect of greatly decreasing the decolorization time to 80 min. Color difference analysis revealed the process of pigment removal during GRO decolorization. The UV–visible full-wavelength scan showed that most pigments were removed after decolorization. The characterizations by the Fourier-transform infrared spectroscopy and X-ray diffraction analysis showed that the chemical structure and crystallinity of the GROs did not change upon decolorization. In addition, the molecular weight distribution did not change significantly. This research contributes to further exploration of the structures and functions of GROs. [ABSTRACT FROM AUTHOR]

The ultrasound-assisted extraction process of vanadium from the aqueous phase to the organic phase by methyltrioctylammonium chloride (MAC) was studied. The factors that influence the vanadium extraction rate such as stirring speed, temperature, and ultrasound power were investigated. The rate expression of vanadium extraction with ultrasound was established. The extraction process could consist of diffusion and chemical capturing steps at the aqueous-organic interface. This study demonstrated that the diffusion resistance could be eliminated by increasing the stirring speed and ultrasound power. The vanadium extraction process without diffusion resistance conformed to the first-order kinetic model. The activation energy (E a) of this extraction process was determined as 36.7 kJ mol−1 along with a pre-exponential factor k 0 a as 3.27 × 105 s−1, while the ultrasound enhancement factor can be expressed as ε = 1 + 1.40 × 10−2 P - 6.61 × 10−5 P 2. The optimal extraction kinetics are identified by examining the factors affecting the vanadium extraction rate (r extr), which are stirring speed ≥ 200 rpm, ultrasound power (P) = 90 W, extraction temperature (T) = 318.15 K. This study provides a theoretical basis for the extraction process of vanadium and aids the design of ultrasound-assisted extraction applications. [Display omitted] • A kinetic model for ultrasonic vanadium extraction was established. • An enhancement mechanism of ultrasonic vanadium extraction was determined. • A quantitative relationship among the ka ε, P , and T was illustrated. [ABSTRACT FROM AUTHOR]

Ultrasound-assisted melt-extrusion method (USME) is a high-quality process used to produce polymeric compounds with an adequate homogeneous dispersion. This study evaluates white-color films of linear low-density polyethylene (LLDPE) prepared using TiO2 masterbatch obtained by ultrasound-assisted melt-extrusion at variable frequencies (USME-VF). LLDPE with three different melt-flow indices (2, 20 and 50 g/10 min) were used as the polymer matrix. The films were obtained from the dilution of masterbatches of LLDPE (melt-flow index = 2) at a concentration of 7 wt% TiO2. The morphology, pigmentation, TiO2 reactivity, and the mechanical stability of the films were assessed. The masterbatch compounds were evaluated by melt-flow index (MFI) and scanning electron microscopy (SEM). The contrast ratio, yellowness index and mechanical properties of films were also measured. The properties of whiteness and elongation at break improved in the films prepared using masterbatches with higher dispersion. Though the reactivity of the TiO2 particles increased during accelerated aging, it did not affect the elongation to rupture. The yellowness index was moderately affected in films that included TiO2 particles processed using USME-VF.

In this work ultrasound-assisted solid-state enzymatic hydrolysis of rice bran to obtain fermentable sugars was investigated. For this purpose, process variables such as temperature, enzyme concentration and moisture content were evaluated during the enzymatic hydrolysis with and without ultrasound irradiation. The enzyme used is a blend of amylases derived from genetically modified strains of Trichoderma reesei. Kinetic of the enzymatic hydrolysis of rice bran at the constant-reaction rate period were measured. The best results for the ultrasound-assisted enzymatic hydrolysis was obtained using 3 wt% of enzyme, 60 oC and moisture content of 65 wt%, yielding 0.38 g sugar/g rice bran, whereas for the hydrolysis in the absence of ultrasound the highest yield was 0.20 g sugar/g rice bran using 3 wt% of enzyme, 60 oC and moisture content of 50 wt%. The use of ultrasound-assisted enzymatic hydrolysis of rice bran was intensified, obtaining around 74% more fermentable sugar than in the absence, showing that the use of ultrasound is a promising technology to be used in enzymatic reaction as an alternative of process intensification.

In this study, simple ultrasound-assisted method was used for prepare the composite of (Cu-doped PVA) interfacial layer between metal and semiconductor (Al/p-Si). The scanning electron microscopy (SEM) images of the prepared (Cu-doped PVA) nanocomposites have shown an uniform fish scale shape, which are about 100 nm long and several tens of nm in width. Both the Al/p-Si (MS) and Al/(Cu-PVA)/p-Si (MPS) structures were fabricated on the same Si wafer to investigate the effect of this polymer layer on the electrical characteristics by using the current-voltage (I-V) and capacitance/conductance-voltage (C/G-V) measurements at room temperature. The values of reverse-saturation current ( I o ), ideality factor (n) and zero-bias barrier height ( Φ Bo ) were obtained from the liner part of the forward bias I-V plot as 6.6 × 10 −10 A, 3.67 and 0.84 eV for MS structure and 1.82 × 10 −8 A, 4.18 and 0.76 eV for MPS structure, respectively. MPS structure has a good rectifier behavior with low leakage current in comparison to the MS structure. The high values of n was attributed to the barrier inhomogeneity at Al/p-Si, special density distribution of N ss at (Cu-PVA)/p-Si interface and both the existence of native SiO 2 and deposited of (Cu-doped PVA) interlayer at M/S interface. The energy dependent values of N ss were obtained from the forward bias I-V data and they ranged from the 1.85 × 10 13  eV −1 cm −2 (0.60 eV - Ev ) to 7.40 × 10 13  eV −1 cm −2 (0.40 eV - Ev ) for MS structure and 9.81 × 10 12  eV −1 cm −2 (0.67 eV - Ev ) to 5.26 × 10 13  eV −1 cm −2 (0.47 eV - Ev ) for the MPS structure. Experimental results show that the (Cu-PVA) interlayer can be successfully used instead of traditional insulator layer because of the saturation of dangling bonds. [ABSTRACT FROM AUTHOR]

A series of ZSM-5 zeolites with tunable mesoporosity were synthesized by a facile ultrasound-assisted method. XRD, FT-IR and NH 3 -TPD results exhibited that as-synthesized ZSM-5 kept the MFI structure as well as the original acidity. Traced by TEM techniques, the crystallization process, especially the state of initial amorphous gel, was found notably affected by the ultrasound treatment by breaking the weak bonds, which led to formation of mesopores in crystals. The ZSM-5 catalysts with abundant mesoprores inhibited coking significantly and showed high catalytic stability for methanol to propylene reaction. The Z5-us-60 catalyst exhibited the highest catalytic stability for >600 h at a high WHSV of 4.0 h −1 . [ABSTRACT FROM AUTHOR]

Abstract: An ultrasound-assisted switchable-hydrophilicity solvent (SHS)-based homogeneous liquid-liquid microextraction (UA-SHS-HLLME) coupled to gas chromatography-mass spectrometry (GC-MS) detection was applied to determine paraquat (PQ) in biological and environmental samples. A chemical reduction of the analyte was performed to produce a volatile derivative of PQ by adding sodium borohydride (NaBH4) to the sample solution. The reduced PQ derivative was extracted into triethylamine (TEA). Two ionic and non-ionic forms (TEA and protonated triethylamine carbonate, P-TEA-C) were reversed by adding or removing CO2. The two phases were separated by addition of sodium hydroxide. Ultrasound was used to form fine droplets of the extractant in the sample solution. The effects of some important parameters on the extraction recovery of the reduced PQ derivative were assessed. Under optimum conditions, the limits of detection and the limits of quantification were found in the range of 0.06-0.13 and 0.20-0.30 µg L−1 with preconcentration factors between 150 and 230 in biological and environmental samples, respectively. The intraday precision was less than 8% (n = 5) and the interday precision was less than 9% (n = 5). The applicability and accuracy of the method were tested by the analysis of spiked real samples. The obtained results indicated that the developed method could be an efficient analytical method for analysis of biological and environmental samples.Graphical Abstract: [ABSTRACT FROM AUTHOR]

In this study, the CuS nanoparticles loaded on activated carbon (CuS‐NPs‐AC) composite was synthesized and then, characterized by XRD and FE‐SEM analyses. The prepared composite was used as a potential adsorbent for the simultaneous ultrasound‐assisted removal of Indigo Carmine (IC) and Safranin‐O (SO). The CuS‐NPs‐AC dose (0.01‐0.03 g), sonication time (1‐5 min), initial SO concentration (5‐15 mg L‐1) and initial IC concentration (5‐15 mg L‐1) as expectable effective parameters were studied by central composite design (CCD) under response surface methodology (RSM) to obtain an useful knowledge about the effect of simultaneous interaction between IC and SO on their removal percentage. The optimum SO and IC removal percentages were determined to be 98.24 and 97.15% at pH = 6, 0.03 g of the CuS‐NPs‐AC, 3 min sonication time, 12 and 10 mg L‐1 of IC and SO. The values of coefficient of determination (R2) for SO and IC were 0.9608 and 0.9796, respectively, indicating the favorable fitness of the experimental data to the second order polynomial regression model. The isotherm data were well correlated with Freundlich model. The maximum monolayer adsorption capacities of 87.5 and 69.90 mg g‐1 at room temperature for IC and SO in the investigated binary system expressed the high efficiency of the novel adsorbent for water cleanup within a short time. The investigation of correlation between time and rate of adsorption revealed that IC and SO adsorption onto the CuS‐NPs‐AC followed pseudo‐second‐order and intra‐particle diffusion simultaneously. [ABSTRACT FROM AUTHOR]

Molecular imprinting is a powerful technology to create artificial receptors within polymeric matrices. Although it was reported for the first time by Polyakov, eighty-four years ago, it remains, nowadays, a very challenging research area. Molecularly imprinted polymers (MIPs) have been successfully used in several applications where selective binding is a requirement, such as immunoassays, affinity separation, sensors, and catalysis. Conventional methods used on MIP production still use large amounts of organic solvents which, allied with stricter legislation on the use and release of chemicals to the environment and the presence of impurities on final materials, will boost, in our opinion, the use of new cleaner synthetic strategies, in particular, with the application of the principles of green chemistry and engineering. Supercritical carbon dioxide, microwave, ionic liquids, and ultrasound technology are some of the green strategies which have already been applied in MIP production. These strategies can improve MIP properties, such as controlled morphology, homogeneity of the binding sites, and the absence of organic solvents. This review intends to give examples reported in literature on green approaches to MIP development, from nano- to micron-scale applications. [ABSTRACT FROM AUTHOR]

The coal-based solid acid catalysts are synthesized by incomplete carbonization followed by sulfonation approach and their activities in catalyzing esterification of oleic acid with methanol are subsequently investigated. For characterizations of catalyst, N 2 adsorption and desorption, ultimate analysis, XRD, SEM, XPS, TG, FTIR and acid amount test are employed. The synthesis conditions are optimized as carbonization at 400 °C for 1 h and sulfonation at 105 °C for 2 h, where acid amount of 1.57 mmol·g −1 is measured. Ultrasound irradiation is introduced into the esterification reactor, and the effects of different operation parameters, including the ultrasonic power, catalyst dosage, molar ratio of methanol to oleic acid, reaction temperature on the esterification efficiency under ultrasound-assisted as well as sonication-free method, have been investigated. The results demonstrate that after passing the given reaction duration of 1 h, 91.4% of esterification efficiency is obtained under the optimized conditions (i.e., ultrasonic power of 270 W, catalyst dosage of 6 wt.%, methanol to oleic acid molar ratio of 10, and reaction temperature of 67 °C). 87.9% of conversion is achieved under the same operating conditions without ultrasonic irradiation. Moreover, esterification experiments indicate that this synthesized coal-based solid acid catalyst possesses favorable catalytic activity and satisfactory recyclability in biodiesel production. [ABSTRACT FROM AUTHOR]

A facile and environmentally friendly strategy for grafting polymers onto the surface of multi-walled carbon nanotubes (CNTs) was demonstrated by Diels-Alder “click chemistry”. Firstly, the copolymers of poly(styrene- alt -maleic anhydride) (PSM) were prepared by the reversible addition-fragmentation chain transfer (RAFT) polymerization and subsequently functionalized with furfuryl amine to introduce anchoring groups. The copolymers were then grafted on CNTs via the Diels-Alder reaction in water through a conventional heating-stirring route and ultrasound-assisted method. The obtained nanocomposite materials were characterized by thermogravimetric analysis, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, Raman spectroscopy and transmission electron microscopy. The results indicated that the reaction rate under ultrasound irradiation was accelerated about 12 times than the one under the conventional heating-stirring condition without losing the grafting efficiency. The direct functionalization of CNTs formed a stably dispersed solution in water, promising a green and effective method for industrial process. [ABSTRACT FROM AUTHOR]

Waterborne nanoemulsion of diglycidyl ether of bisphenol A type epoxy resin (DGEBA) with droplet size of around 124 nm was prepared by using an ultrasonic-assisted supercritical carbon dioxide (scCO 2 ) technique in an autoclave reactor at a low temperature (32 °C). A view cell positioned in-line with the ultrasonic probe allowed observation of the emulsification process. From the image analysis and droplet size measurement, the influence mechanisms of the ultrasonic power, the degree of mixing of scCO 2 with DGEBA, the adding amount of emulsifier, and the system pressure on emulsification process and emulsion droplet size were investigated. In the emulsification process, scCO 2 penetrated into the mixture and absorbed on the DGEBA molecular. The interactions between CO 2 and the functional groups of DGEBA reduced the chain-chain interactions of polymer segments and therefore efficiently reduced the viscosity of DGEBA at a low temperature. Meantime, the cavitation and acoustic streaming of ultrasound provided a shear force for the nanoemulsification and a disturbance force for the homogeneity of the emulsion. Therefore, the combination of scCO 2 and ultrasonication made it possible to prepare a long-term stable nanoemulsion under a low temperature. This ultrasonic-assisted scCO 2 emulsification method provides an efficient and solvent-free process for the preparation of waterborne nanoemulsions of, for example, some heat-sensitive and water-insoluble active substances at low temperature. [ABSTRACT FROM AUTHOR]

• Initial study by ultrasound-assisted dispersive solid-phase extraction using magnesium ferrite as a magnetic adsorbent. • The spectrophotometric method was successfully applied. • Response surface methodology was used to optimize the extraction of dyes. • The proposed method was sensitive, fast, inexpensive, reliable, simple, and eco-friendly. This study aimed to determine of malachite green (MG) and auramine O (AO) dyes in different environmental water samples. For this purpose, MG and AO dyes were pre-concentrated by ultrasound-assisted dispersive solid-phase extraction (UA-DSPE) and measured by spectrophotometry. Magnesium ferrite (MgFO) was applied as a magnetic adsorbent in the UA-DSPE-UV/Vis method. The effect of different parameters on the dye extraction efficiency, including pH of the solution, sorbent mass, sample volume, ultrasound frequencies, irradiation time, and type and volume of eluent, were investigated. In addition, response surface methodology (RSM) approach-based central composite design (CCD) was used to design and optimize parameters affecting the process. Analysis of variance (ANOVA) results based on high F-values, low p-values, coefficient of determination (R2 > 0.99), and adjusted-R2 (R2adj > 0.99) revealed that the quadratic model was the best model for defining the interaction of the studied variables. The calibration curve, the limit of detection (LOD), and relative standard deviation (RSD, n = 5) for MG and AO dyes were 1–800 ng mL−1 and 3–1200 ng mL−1, 0.33 ng mL−1 and 1 ng mL−1, and 3.2% and 2.8%, respectively. The effect of some external species (including cations and anions) on the determination of MG and AO dye was investigated. The results revealed that adding different ions does not significantly interfere with determining MG and AO dyes. The reusability of the MgFO adsorbent showed that it could be reused for up to 7 cycles, maintaining its high efficiency in the extraction of MG and AO dyes. Moreover, the proposed method was used for the extraction of MG and AO dyes from different water samples. The obtained extraction efficiency was in the range of 95.37–99.54%. [ABSTRACT FROM AUTHOR]

[Display omitted] • The highly selective separation of palladium from spent catalyst by ozone/ultrasonic is proposed. • The leaching percentage of palladium is 93.7% at low-acid medium of 0.4 M. • The leaching process is driven by ultrasonic disaggregating of the cladding layer and active free radicals. It is of great significance to consider the recovery of palladium from spent catalyst in terms of resource reserve and environmental protection. However, the leaching percentage of palladium is limited by high oxidation potential and cladding layer. In order to solve this process problem, external field enhancement method with ultrasonic-assisted ozone is proposed for the recycling of palladium in this study. Mechanical and cavitation effects of ultrasonic can destroy cladding layer and promote solid–liquid interface reaction. The highly oxidizing free radicals generated by ultrasonic excitation of ozone can improve the oxidation of the reaction system and accelerate the oxidation rate of palladium. The leaching percentage of palladium is 93.7% under ultrasonic/ozone condition, which is 23.7% higher than that under conventional conditions. The leaching reaction kinetics shows that the reaction barrier is reduced and the apparent activation energy is reduced by 35.25 kJ/mol after introducing ultrasound and ozone. Additionally, mineralogical analysis is carried out to analyze the enhanced leaching mechanism of palladium. This work demonstrates the value of advanced oxidation process with ultrasonic-assisted ozone in efficient and green recovery of precious metals from secondary resources. [ABSTRACT FROM AUTHOR]

[Display omitted] The study evaluated the effect of an ultrasound-assisted treatment on the structural and functional properties of sheep bone collagen (SBC). The type and distribution of SBC were analyzed by proteome (shotgun) technology combined with liquid chromatography-tandem mass spectrometry. Compared with pepsin extraction, the ultrasound-assisted treatment significantly increased the collagen extraction rate by 17.4 pp (P < 0.05). The characteristic functional groups and structural integrity of collagen extracted by both methods were determined via Fourier transform infrared spectroscopy, ultraviolet absorption spectroscopy, and fluorescence spectroscopy. Circular dichroism spectra revealed that the ultrasound-assisted pretreatment reduced α-helix content by 1.6 pp, β-sheet content by 21.9 pp, and random coils content by 28.4 pp, whereas it increased β-turn content by 51.9 pp (P < 0.05), compared with pepsin extraction. Moreover, ultrasound-assisted treatment collagen had superior functional properties (e.g., solubility, water absorption, and oil absorption capacity) and foaming and emulsion properties, compared with pepsin extraction. Furthermore, the relative content of type I collagen in ultrasound-assisted extracted SBC was highest at 79.66%; only small proportions of type II, VI, X, and XI collagen were present. Peptide activity analysis showed that SBC had potential antioxidant activity, dipeptidyl peptidase 4 inhibitory activity, and angiotensin-converting enzyme inhibitory activity; it also had anticancer, antihypertensive, anti-inflammatory, and immunomodulatory effects. [ABSTRACT FROM AUTHOR]

S-doped and Cu- and Co-doped TiO 2 was synthesized by a sol–gel method and characterized by FE-SEM, XRD, EDX and FTIR. The Co/Cu/S-TiO 2 nanocomposite loaded on the activated carbon as new nanoadsorbent was used for simultaneous removal of methylene blue (MB) and sunset yellow (SY) from aqueous solution by ultrasonic-assisted adsorption method. In this work, central composite design (CCD) and adaptive neuro-fuzzy inference system (ANFIS) as a support tool for examining data and making prediction are used to recognize and predict the removal percentage in MB and SY dye solution of different concentrations. The predictive capabilities of CCD and ANFIS are compared in terms of square correlation coefficient ( R 2 ), root mean square error (RMSE), mean absolute error (MAE) and absolute average deviation (AAD) against the empirical data. It is found that the ANFIS model shows the better prediction accuracy than the CCD model. In addition to, the optimization of ultrasound-assisted simultaneous removal of methylene blue (MB) and sunset yellow (SY) on the Co/Cu/S-TiO 2 /AC nanocomposite by response surface methodology (RSM) for the optimization of the process variables, such as MB and SY concentrations, Co/Cu/S-TiO 2 /AC nanocomposite dose and sonication time, was investigated. Various isotherm and kinetic models were used in the experimental data. The results revealed that the langmuir isotherm and pseudo-second-order model had a better correlation than the other models. [ABSTRACT FROM AUTHOR]

In this paper, the ultrasound-assisted leaching of iron from boron carbide waste-scrap was investigated and the optimization of different influencing factors had also been performed. The factors investigated were acid concentration, liquid-solid ratio, leaching temperature, ultrasonic power and frequency. The leaching of iron with conventional method at various temperatures was also performed. The results show the maximum iron leaching ratios are 87.4%, 94.5% for 80 min-leaching with conventional method and 50 min-leaching with ultrasound assistance, respectively. The leaching of waste-scrap with conventional method fits the chemical reaction-controlled model. The leaching with ultrasound assistance fits chemical reaction-controlled model, diffusion-controlled model for the first stage and second stage, respectively. The assistance of ultrasound can greatly improve the iron leaching ratio, accelerate the leaching rate, shorten leaching time and lower the residual iron, comparing with conventional method. The advantages of ultrasound-assisted leaching were also confirmed by the SEM-EDS analysis and elemental analysis of the raw material and leached solid samples. [ABSTRACT FROM AUTHOR]