Application Of Ultrasonication Research Articles

Conjoint application of ultrasonication and redox pair mediated free radical method enhances the functional and bioactive properties of camel whey-quercetin conjugates

Ultrasonication, redox-pair generated free radical method and their combination (Ultrasonication/redox-pair method) was used for production of camel whey-quercetin conjugates. FTIR and SDS-PAGE confirmed successful production of whey-quercetin conjugates using ultrasonication and ultrasonication/redox-pair method. FTIR suggested existence of covalent (appearance of new peak at 3399 cm−1) and non-covalent linkages (shifting of peak at 3271 cm−1, 1655 cm−1 (amide I), 1534 cm−1 and 1422 cm−1 (Amide II)) in the whey-quercetin conjugates. Moreover, SDS-PAGE of conjugates produced by ultrasonication as well redox-pair method indicated shifting of protein bands slightly towards high molecular weight due to increase in the mass of proteins due to the binding of polyphenols. All conjugates showed improved techno-functional and bioactive properties in comparison to whey proteins. Conjugates produced through ultrasonication showed smaller particle size, improved solubility, emulsifying and foaming properties while conjugates produced through ultrasonication/redox-pair method depicted superior antioxidant properties in comparison to whey. Furthermore, conjugated samples showed higher inhibition of enzymatic markers involved in diabetes and obesity with highest potential recorded in conjugates produced using ultrasonication. Therefore, ultrasonication can be successfully used individually as well as in combination with redox-pair for production of whey-quercetin conjugates with enhanced bioactive and techno-functional properties.

Ultrasonication promotes extraction of antioxidant peptides from oxhide gelatin by modifying collagen molecule structure

This study primarily explored the internal mechanism underlying the ultrasonication-induced release of antioxidant peptides. An oxhide gelatin solution was treated ultrasonically (power = 200, 300, and 400 W), followed by enzymatic hydrolysis and structural and morphological analysis. The results showed that ultrasonication increased not only the degree of hydrolysis (DH) and protein recovery rate of the oxhide gelatin but also the ABTS radical scavenging, DPPH radical scavenging, ferrous chelating, and ferric reducing activities of its hydrolysate. The oxhide gelatin hydrolysate treated with 300-W ultrasonication had the maximum antioxidant activities. Ultrasonication inhibited hydrogen bond formation, reduced the crosslinking between collagen molecules, transformed part of the folded structure into a helical structure, and lowered the thermal stability of collagen molecules. The micromorphological analysis revealed that ultrasonication caused the gelatin surface to become loose and develop cracks, and as the power of the ultrasonication increased, the repetition interval distance (dÅ) also increased. Moreover, ultrasonication improved the solubilization, surface hydrophobicity, and interface characteristics and increased the content of basic and aromatic amino acids in the hydrolysate. In conclusion, ultrasonication modifies the protein structure, which increases the enzyme’s accessibility to the peptide bonds and further enhances antioxidant peptide release. These findings provide new insights into the application of ultrasonication in the release of antioxidant peptides.

Enhanced heavy metal leaching from sewage sludge through anaerobic fermentation and air-assisted ultrasonication

Interest in using stabilized sewage sludge in agriculture is mainly to benefit from its nutrient content, soil conditioning properties, and water holding capacity. Therefore, sludge management practice needs to be directed from treatment liability towards the recovery of chemical assets embedded in sludge. In this study, anaerobic fermentation process integrated with a new treatment method; i.e., air-assisted ultrasonication, was used to assess the leaching of heavy metals (HM) from waste activated sludge (WAS). Fermentation processes resulted in 9390 mg COD/L of volatile fatty acids (VFAs) production, 26% Ni solubilization and up to 3.4% solubilization of other target metals (Cu and Zn). Application of the air-assisted ultrasonication as a post-treatment to fermentation process stimulated the migration and transformation of HMs to the liquid fraction of the digestate. Applying specific energy input greater than 9 kJ/g total solids (TS) through ultrasonication and supplying air with constant flow rate of 0.875 L of air/(L of digestate.min) resulted in leaching of more than 83% of Ni, 82% of Cu and 80% of Zn.

The Application of Ethanolic Ultrasonication to Ameliorate the Triterpenoid Content Extracted from Vietnamese Ganoderma lucidum with the Examination by Gas Chromatography

AbstractIn this study, to investigate the extraction of triterpenoids from the Vietnamese red G. lucidum by ultrasound‐assisted extraction (UAE) method using ethanol as a solvent, the determination of the four single factors influence on the triterpenoid content including liquid‐to‐solid ratio, extraction power, extraction temperature, and extraction time was carried out for the performance of experiments on simultaneous effects by Central Composite design. The results showed that based on ultraviolet‐visible spectroscopy analysis, the highest yield of triterpenoids could be achieved with value of 18.3751 mg/g under optimal extraction conditions including extraction time of 60 min, ultrasonic power of 360 W, liquid‐to‐solid ratio of 38 : 1 mL/g, and ultrasonic temperature of 48 °C. To determine the characteristics of the obtained extract, the Gas chromatography‐mass spectrometry, the Fourier‐transform infrared spectroscopy, scanning electron microscope, and the thermogravimetric analyzer were employed in this study. Besides, for antioxidant capacity evaluation, the DPPH free radical scavenging assay, H2O2 scavenging assay, and the ABTS radical cation decolorization assay were carried out whereas the anticancer evaluation results denoted the potential for anticancer agents of G. lucidum extract. Therefore, it could be concluded that UAE is a promising method for triterpenoid extraction with antioxidant properties.

Application of ultrasonication at different microbial growth stages during apple juice fermentation by Lactobacillus plantarum: Investigation on the metabolic response

In this work, low-intensity ultrasonication (58.3 and 93.6 W/L) was performed at lag, logarithmic and stationary growth phases of Lactobacillus plantarum in apple juice fermentation, separately. Microbial responses to sonication, including microbial growth, profiles of organic acids profile, amino acids, phenolics, and antioxidant capacity, were examined. The results revealed that obvious responses were made by Lactobacillus plantarum to ultrasonication at lag and logarithmic phases, whereas sonication at stationary phase had a negligible impact. Sonication at lag and logarithmic phases promoted microbial growth and intensified biotransformation of malic acid to lactic acid. For example, after sonication at lag phase for 0.5 h, microbial count and lactic acid content in the ultrasound-treated samples at 58.3 W/L reached 7.91 ± 0.01 Log CFU/mL and 133.70 ± 7.39 mg/L, which were significantly higher than that in the non-sonicated samples. However, the ultrasonic effect on microbial growth and metabolism of organic acids attenuated with fermentation. Moreover, ultrasonication at lag and logarithmic phases had complex influences on the metabolism of apple phenolics such as chlorogenic acid, caffeic acid, procyanidin B2, catechin and gallic acid. Ultrasound could positively affect the hydrolysis of chlorogenic acid to caffeic acid, the transformation of procyanidin B2 and decarboxylation of gallic acid. The metabolism of organic acids and free amino acids in the sonicated samples was statistically correlated with phenolic metabolism, implying that ultrasound may benefit phenolic derivation by improving the microbial metabolism of organic acids and amino acids.

Kinetic modeling and process intensification of ultrasound-assisted extraction of d-limonene using citrus industry waste

Citrus limetta is a widely-processed fruit that generates 40 % peel waste involving considerable constraints for waste management. Citrus limetta peel is a rich source of essential oil, especially d-limonene, commonly used as a fragrance and flavor ingredient. This study investigated the application of ultrasonication as a process intensification tool with improved extraction-efficiency. Peleg’s mathematical model was used to study the kinetics of ultrasound-assisted extraction (UAE) of d-limonene. The use of UAE reduces the total extraction time to 20 min compared to 185 min in a conventional process. In UAE, the highest extraction yield of d-limonene (32.9 mg/g, 97 %) was obtained using hexane as food-grade solvent, biomass:solvent ratio of 1:10, 2 mm particle size, agitation speed 300 rpm, temperature 60°C with ultrasonic power 80 W, 50 % duty cycle and frequency 25 kHz. Analysis and characterization of the extract were carried out using HPLC, GC-MS, and FTIR. Also, the surface morphology of raw material after extraction was studied using SEM analysis. The acceptable agreement was seen in the calculated values of Ceq from Peleg’s mathematical model and actual experimental results of extracted d-limonene. UAE stands as a fast, efficient, and economical method for the extraction of d-limonene from the fresh sweet lime peel.

An application of ultrasonication in lignocellulosic biomass valorisation into bio-energy and bio-based products

The industrial revolution has caused a tremendous impact on our modern way of life. It shapes the economic, social and culture of many modern societies around the world. However, the world's heavy dependence on fossil fuels has exacerbated the effect of modernisation, causing a detrimental effect to the world climate. Recently, the scientific community has shifted their focus to the valorisation of lignocellulosic biomass as a renewable and clean source of energy. Lignocellulosic biomass is a potential substitute for fossil fuel as it could be transformed to various bio-energy and bio-based products by biorefineries. However, the recalcitrant nature of lignocellulosic biomass hinders the commercialisation at large scale due to the processing difficulties and economically not viable. Hence, ultrasound has been utilised as an auxiliary energy to intensify pretreatments as well as biorefinery processes in the productions of bio-fuels and fine chemicals. In this review, the background information of lignocellulosic biomass and ultrasound is provided. Furthermore, the applications of ultrasound as a complement to existing pretreatments and bioprocessing technologies are discussed by highlighting the importance of mechanoacoustic and sonochemical effect produced by the ultrasound. Lastly, technoeconomic analysis and socioeconomic impact of utilising ultrasound in the biomass processing are elaborated to provide a holistic view on the novel and environmentally friendly green technique.

Application of Ultrasonication to Intensify the Thermal Cracking of Fuel Oil in a Mixture with Oil Shale

The results of the determination of the effect of low-frequency ultrasonic treatment on the thermal cracking of fuel oil mixed with shale from the Kendyrlyk deposit (Republic of Kazakhstan) are reported. It has been established that, upon the addition 12% Kendyrlyk shale to fuel oil with the subsequent ultrasonic treatment of the mixture, the maximum yields of a gasoline fraction with bp to 180°C and a diesel fraction with bp 180–360°C were as high as 20.4 and 44.9%, respectively.

Development of a method of hollow fiber-based solid-phase microextraction followed by ultra performance liquid chromatography-tandem mass spectrometry for determination of five antipsychotics in human whole blood and urine

This work focused on the development and validation of a method based on hollow fiber-based solid-phase microextraction coupled to ultra-performance liquid chromatography tandem mass spectrometry (HF-based-SPME-UPLC-MS/MS) for the determination of five antipsychotics at a pg mL–1 level in human whole blood and urine. Four types of hollow fiber membrane materials, including polyether sulfone, polypropylene, polyvinyl chloride and polyvinylidene fluoride were investigated. Finally, polyether sulfone hollow fiber without any modification was selected as the adsorption medium for solid-phase microextraction (SPME) with the following extraction procedure: the analytes were adsorbed onto the hollow fiber in the sample bottle with application of ultrasonication. Subsequently, the hollow fiber was transferred into a slim glass tube containing an appropriate solvent, and the analytes were desorbed by ultrasound treatment before detection by UPLC-MS/MS. In order to obtain satisfactory extraction efficiency, extraction parameters such as hollow fiber membrane material, pH, hollow fiber length, extraction time, desorption solvent and desorption time were investigated. Under the optimum experimental conditions, this method allowed for determination of five antipsychotics in human whole blood with excellent limits of quantification (LOQs) (25.0, 12.5, 25.0, 25.0 and 12.5 pg mL–1 for perphenazine, chlorpromazine, chlorprothixene, promethazine and trifluoperazine, respectively). The corresponding LOQs in human urine were 25.0, 12.5, 12.5, 12.5 and 12.5 pg mL–1 for the respective antipsychotics. The precision (RSD) was no more than 13.3%. The extraction recoveries for human whole blood and urine were in the range of 46.4–96.6% and 65.2–101.9%, respectively. The proposed method was compared with other methods from the literature and the results demonstrate that it is a simple, sensitive, efficient and green technique. It is suitable for analyzing trace target analytes in complex matrices such as biological samples and can provide a reliable tool for drug monitoring especially in forensic analysis and case of drug abuse.

Flux evaluation based on fouling mechanism in acoustic field-assisted ultrafiltration for cold sterilization of tender coconut water

Membrane-based processing was attempted as a clean, green and energy-efficient method for cold sterilization of tender coconut water (TCW). Ultrafiltration of TCW was carried out at four different pressures employing two different polyethersulfone membranes, using a stirred cell. Permeate flux was evaluated based on different fouling mechanisms which are analysed employing Hermia's model. The objective of the study was to examine the efficacy of ultrafiltration for cold sterilization of TCW while retaining good sensory quality. The effect of acoustic field (ultrasonication) on the performance of ultrafiltration has been evaluated. Permeate flux increased on the application of ultrasonication. Enzyme activities in TCW permeate were found to reduce after ultrafiltration with good sensorial acceptability. Microbial load of TCW after ultrafiltration was observed to decrease from 4.16 to 0.0 log CFU/mL, achieving cold sterilization. Sensorial quality of ultrafiltered TCW was found to be good after three months storage period with zero microbial count.

Self-assembly of amphiphilic poly(styrene-b-acrylic acid) on magnetic latex particles and their application as a reusable scale inhibitor.

The deposition of scale on membranes or container and pipe surfaces (clogging the system) is a costly issue in water treatment processes or water-cooling systems. To effectively cope with this issue, magnetic polymeric nanoparticles (MPNPs) have been developed and applied as promising scale inhibitors, due to their high surface-area-to-volume ratio, surface modifiability, and magnetic separation ability. Carboxylated MPNPs, having a monodisperse size distribution (236 ± 26 nm) with a high magnetic content of 70 wt% and superparamagnetic properties, were fabricated by using a 2-step process: (i) formation of clusters of hydrophobic magnetic nanoparticles stabilized by oleic acid (OA-MNPs), and (ii) self-assembly of the amphiphilic block copolymer of poly(styrene27-b-acrylic acid120) (PS27-b-PAA120) onto the cluster surfaces. With application of ultrasonication to 12.0 wt% OA-MNPs, a three-dimensional network was formed by particle–particle interactions, suppressing coalescence, and then creating stable magnetic clusters. The cluster surfaces were then adsorbed by amphiphilic PS27-b-PAA120via the attractive force between hydrophobic PS blocks. This moves longer hydrophilic PAA blocks containing carboxylic acid groups into the water phase. The formulated MPNPs acted as a nanosorbent for calcium ion (Ca2+) removal with a removal efficiency of 92%. The MPNPs can be effectively reused for up to 4 cycles. Based on the electrostatic interactions between the negatively-charged polymer and the hydrated Ca2+, the resulting precipitation leads to the prevention of calcium carbonate scale formation. Insights into this mechanism open up a new perspective for magnetic-material applications as effective antiscalants.

Određivanje elemenata u kosi metodom ICP-MS

Human hair is a biological sample that is, unlike blood, noninvasively collected and can be used in the assessment of element intake. Before analysis, hair samples need to be washed to eliminate external contamination, for which no standard procedure exists. The present study evaluated the efficiency of different processes for washing hair samples (by non-ionic detergent, acids, solvents, and their mixtures), including ultrasonication before ICP-MS element (As, Ca, Cd, Cu, Fe, Hg, Mg, Mn, Mo, Pb, Se, and Zn) analysis. All tested washing procedures using detergent or solvents were satisfactory, while nitric and hydrochloric acid solutions yielded to “released” and lost elements due to damaged hair (visible discolouration and hair impairment). The application of ultrasonication improved washing efficiency up to 10 %, depending on the tested element and washing procedure.

A study on combined effect of Fenton and Free Nitrous Acid treatment on sludge dewaterability with ultrasonic assistance: Preliminary investigation on improved calorific value

Increase in sludge dewatering plays an important role in reducing its treatment, handling and disposal costs. In this work, efficacy of various sludge dewatering techniques such as Fenton (F), Free Nitrous Acid (FNA) and F/FNA was performed under ultrasonication. Experiments were carried out to determine the amount of sludge filtrate and Capillary Suction Time (CST) under various conditions. The optimum pH was found to be 3, 3 and 5 respectively for Fenton, FNA and F/FNA. More amount of sludge filtrate was detected for treated sludge in the order F/FNA (57 mL) > FNA (55 mL) > Fenton (48 mL) and minimum CST was observed in F/FNA (28 s) < FNA (31 s) < Fenton (49 s). SEM and DSC analysis were performed to observe the variation in physical characteristics before and after treatment. The change in functional groups in sludge cake before and after treatment was investigated using FT-IR. Excitation-Emission Matrix (EEM) was used to measure the fluorescence peak and intensities of the released biopolymers into sludge filtrate caused by the disintegration of EPS. In addition, the radical scavenging experiments were also performed to identify the significant roles of hydroxyl (OH·), nitrogen dioxide (NO2·), nitric oxide (NO·) and superoxide (O2·-) radicals. The experimental results indicated that the increased mass transfer due to the application of ultrasonication resulted in higher dewaterability. The leaching of metals from the sludge cake into the treated sludge filtrate portrays that sludge could be utilized as manure and solid biomass fuel.

Ultrasound-Assisted Extraction of Chitosan from Squid Pen: Molecular Characterization and Fat Binding Capacity.

Chitosan from squid (Loligo formosana) pens were prepared and characterized. First, ultrasonication condition was optimized for deproteinization of squid pens using central composite design (CCD) of response surface methodology (RSM). Squid pens were ultrasonicated at amplitude 69% for 41.46 min at the solid/solvent ratio of 1:18 yielded 34% (w/w) chitin with the lowest remaining protein. Therefore, ultrasonication effectively reduced the extraction time for chitin production from squid pens as compared to traditional method (5 hr). When the resultant chitin was subjected to deacetylation at different temperatures and times, yield and degree of deacetylation (DDA) of chitosan were in the range of 50% to 65% (w/w) and 78% to 90%. Intrinsic viscosity and molecular weight (MW) of chitosan were in the range of 3.2 to 6.52 dL/g and 1.2 × 105 to 3.2 × 105 Da, respectively. All the chitosans with different DDA were able to bind oil droplets under the mimicked pH condition of gastrointestinal tract. Chitosan produced by deacetylation at 130 °C for 2 hr (CH130-2) showed the optimum yield (54%) and had medium MW (1.5 × 105 Da). DDA of CH130-2 determined using 1 H-NMR was 89%, which was similar to that (87%) obtained from FTIR. XRD results showed destruction of chitin structure and decreased crystallinity index from 55% to 27% after deacetylation. CH130-2 stabilized the emulsion under the simulated gastrointestinal conditions. Therefore, it could be used as dietary fiber to control the adsorption of fat/oil in the human digestive tract. PRACTICAL APPLICATION: Chitin and chitosan are marketable products manufactured from crustacean shells. However, extraction of chitin is time consuming. Ultrasonication has been used for extraction of various biomolecules from different sources. It effectively lowers the processing time and enhances extraction yield. Therefore, application of ultrasonication with optimized condition using RSM could reduce extraction time and enhance yield of chitin from squid pen. Chitin from squid pen could be further converted to chitosan with high DDA. Chitosan was able to act as a dietary fiber and reduce fat absorption in gastrointestinal tract. Thus, this information is of benefit for squid processing industry to exploit squid pen, a processing byproduct.

Coating pretreatment of banana slices using carboxymethyl cellulose in an ultrasonic system before convective drying

Drying is one of the oldest methods of food preservation. However, this method requires careful promotion and maintenance of the quality of the dried products. In this paper, Carboxymethyl cellulose (CMC) coating and sonication pretreatments were employed as a new approach to improve the efficiency of convective drying and produce dried banana slices with acceptable quality in a short period. To achieve these goals, the effects of ultrasonic power (at three levels of 0, 500, and 1000 W) and sample to CMC coating solution ratio (with three levels of 1:2, 1:3, and 1:4), as well as the mutual effect of these two independent variables, were evaluated. The results showed that increasing the ultrasonic power from 0 to 1000 W decreased the drying time (P ≤ 0.001), energy consumptions of the convective drier (P ≤ 0.001), total energy consumption (P ≤ 0.001), shrinkage (P ≤ 0.001), apparent density (P ≤ 0.001), shear stress (P ≤ 0.001), and the total color change (P ≤ 0.001); it also increased energy consumptions of the ultrasonic system (P ≤ 0.001), porosity (P ≤ 0.001), and TPC (P ≤ 0.001) of the dried banana slices significantly. Moreover, changing the sample to coating solution ratio from 1:2 to 1:4 reduced the shrinkage (P ≤ 0.001), apparent density (P ≤ 0.001), shear stress (P ≤ 0.001), and total color change (P ≤ 0.01); this also led to remarkable increase in the porosity (P ≤ 0.001) and TPC (P ≤ 0.05) of the dried samples. With respect to the cross-sectional scanning electron microscopy (SEM) images of the dried banana slices, it was found that the CMC coating pretreatment in an ultrasonic system, especially with an ultrasonic power of 1000 W and a sample to coating solution ratio of 1:4, enhanced the porosity of the dried banana slices. Overall, the combined application of ultrasonication and Carboxymethyl cellulose coating pretreatments could be considered as an effective approach to improve the quality of the dried products through convective drying.

Optimization of the First Step of Enoxaparin Synthesis by Hydrolytic Depolymerization of Unfractionated Heparin

The first step of low-molecular-mass heparin (enoxaparin) preparation by hydrolytic depolymerization of unfractionated heparin was investigated. The step involved chemical reaction of starting heparin and benzethonium chloride in aqueous saline solutions. The number of acid equivalents in unfractionated heparin was shown to increase as the NaCl concentration increased. This was probably related to effects of the solution ionic strength on the heparin macromolecular conformation, which was confirmed using dynamic light scattering. The average size of the observed light-scattering centers in aqueous heparin solutions decreased with increasing NaCl concentration. Rinsing with H2O and not NaCl solutions and application of ultrasonication were recommended to accelerate purification of benzethonium heparinate from starting materials and to reduce the amount of rinse water. The compositions of the produced and purified benzethonium heparinate samples were confirmed using PMR spectroscopy.

Identification of harmful protozoa in outdoor cultivation of Chlorella and the use of ultrasonication to control contamination

Contaminating organisms in mass cultivation present one of the major challenges that must be overcome for successful commercialization of algal biofuels. The present study identified a range of contaminating organisms in Chlorella cultures cultivated in outdoor raceway ponds at the Arizona Center for Algae Technology and Innovation (Mesa, AZ). Nineteen organisms or Operational Taxonomic Units (OTU) in the Chlorella culture were identified by a combination of microscopic observation and 18S rRNA denaturing gradient gel electrophoresis (DGGE). More detailed analyses identified these contaminating organisms as 2 fungi, 7 flagellates, 3 amoebae, 4 ciliates, 1 rotifer, and 2 large insects. Among them Poterioochromonas sp., a small flagellate, appeared to be one of the most harmful causing culture collapse. In order to control Poterioochromonas sp., various operational parameters and application strategies of ultrasonic treatment were investigated. During sixteen-day consecutive Chlorella cultivation in batch mode, the ultrasonication conditions of 6 L min−1 flow rate with the power of 495 W at 100% amplitude and a treatment frequency of once for 1 h every day, was proven to be the most effective in preventing Poterioochromonas outbreak in Chlorella culture with volume of 60 L. The above ultra-sonication method was also effective at destroying an unknown fungus, an amoeba (Acanthocystis sp.), and ciliates (a member of the family Orchitophryidae). Our findings can serve as a technical foundation for the application of ultrasonication to control some of the contaminating microorganisms in mass cultivation of microalgae including Chlorella.

Controlling the Product Crystal Size Distribution by Strategic Application of Ultrasonication

In this work, different strategies of ultrasonication (continuous, single pulse, and multiple pulse) are compared for control of the product crystal size distribution of three model API compounds: piracetam, paracetamol, and ibuprofen. Experiments have been performed on 0.5 and 3 L scales continuously recorded by FTIR and FBRM. Irrespective of the sonication operating mode, sonication in general produced smaller sized crystals with a more narrow size distribution in comparison to those for a normal cooling crystallization process. A multiple-pulse sonication mode, in particular, was capable of delivering more narrow size distributions. Sonication power per unit mass of solution does not appear to be a relevant scaling-up parameter.

Ultrasound-enhanced electrokinetic remediation for removal of Zn, Pb, Cu and Cd in municipal solid waste incineration fly ashes

Low-frequency ultrasound generated by a transducer was investigated to activate the raw municipal solid waste incineration (MSWI) fly ashes in the electrokinetic process, aiming at enhancing heavy metal (HM) removal and achieving better remedial efficacy. The maximum removal efficiencies of 69.84%, 64.24%, 67.74% and 59.93% were obtained in the orthogonal tests of ultrasonication for Zn, Pb, Cu and Cd, respectively. The acoustic time of 30 min and controlling temperature of 45 °C in the operating parameters were quantitatively determined to optimize the ultrasonication of the MSWI fly ash matrices. The changes of acoustic time had a significant effect on the extraction efficiencies of all the four heavy metal elements in the sonication optimal experiments. The longer running time was preferred for the pretreatment of the fly ashes in according to the marginal mean removal results. The voltage gradient of 2 V/cm was most likely to improve the removals of four HMs during the electrokinetics in the range of 0.5–2 V/cm. The synergetic application of acidification and ultrasonication for the media treatment was demonstrated to be most effective in enhancing the remedial efficiencies in the further electrokinetic experiments compared with the other activation systems. Correspondingly, the leaching concentrations of Zn, Pb, Cu and Cd in the samples were reduced by 85.92%, 98.22%, 88.53% and 98.34%, respectively. The contaminants were continuously extracted from the solid grains of the fly ashes by the protonic attack and bubble implosion. The obtained risk-assessment-code values indicated the adoption of AUS-EKR system reduced the environmental toxicity for the fly ashes to the maximum extent.

Application of Ultrasonication to Factory C Molasses to Improve Viscosity, Sucrose Crystallization, and Extraction

Application of Ultrasonication to Factory C Molasses to Improve Viscosity, Sucrose Crystallization, and Extraction