Effect Of Sonication Power Research Articles

Impact of sonication power on the degradation of paracetamol under single- and dual-frequency ultrasound

The effects of sonication power on the ultrasonic cavitation and sonochemistry as well as the degradation of paracetamol were studied and compared for single- and dual-frequency sonoreactors. For the single-frequency sonication, a 500 kHz plate transducer was employed, with three different calorimetric powers of 8.4, 16.7 and 27.9±3.9 W. For the dual-frequency sonication, the plate transducer was perpendicularly coupled with a low-frequency 20 kHz ultrasonic horn, and three calorimetric powers of 27.9, 33.4, 44.6±3.9 W were studied. At all the studied powers, dual-frequency sonication led to a synergistic effect in the degradation of paracetamol, though varying the power of the horn did not affect the degradation rate. A comparison of the degradation data versus the yield of oxidants as well as the overall intensities of sonoluminescence and sonochemiluminescence suggested the degradation is by the action of oxidants near the surface of the bubbles as the major reaction mechanism. Despite the enhancement observed for the degradation, dual-frequency sonication had no significant effect on the yield of either of the oxidants, regardless of the applied power to the horn. In contrast, dual-frequency sonication decreased the overall sonoluminescence and sonochemiluminescence intensities at all powers studied, suggesting that the application of dual-frequency sonication reduces the size of cavitation bubbles. Normal distribution function analysis confirmed dual-frequency sonication resulted in smaller sonoluminescing bubbles, hence the reduction in the sonoluminescence intensity. The increase in degradation rate under DFUS is attributed to the increase in the transfer of paracetamol from the bulk towards the bubbles. As a result, the availability of the pollutant molecules in the vicinity of the bubbles to react with HO• would increase and consequently, the degradation rate would enhance under DFUS.

D-Limonene as a Promising Green Solvent for the Detachment of End-of-Life Photovoltaic Solar Panels under Sonication

Consumption of photovoltaic solar panels is expected to increase, so the growing amount of end-of-life (EOL) solar panels will require large spaces for their disposal, which at the moment costs around 200 euros/ton. Thus, a proper treatment technique to recover secondary materials from this waste, which are mainly copper, aluminum, silicon, high-transmittance glass, and plastics, must be developed. The last three components are strongly attached to each other; hence, their detachment is necessary for recovery. To achieve this objective, a chemical route was chosen; in fact, solvent extraction is highly recommended, as it has a high separation efficiency. In this study, D-limonene as a bio-solvent was examined for detaching different components of solar panels from each other. A high efficiency for ethylene vinyl acetate (EVA) dissolution and components’ detachment under different conditions was achieved with the help of sonication power. The effects of sonication power, thermal pre-treatment, temperature, and contact time on detachment percentage were examined, and the best conditions (namely, no pre-treatment, medium sonication power of 450 W, temperature of 60 °C, and a contact time of 120 min) were found for total component detachment. Additionally, the recyclability of D-limonene was examined, and it was established that the solvent could carry out 100% component detachment for three cycles.

Dy2Cu2O5 nanostructures: Sonochemical fabrication, characterization, and investigation of photocatalytic ability for elimination of organic contaminants

Economical elimination of organic contamination from sewage has become an enthusiastic study subject owing to its environmental and ecological significance. Conventional water purification techniques, including adsorption, membrane separation, and coagulation, suffer from great operating expenses and even produce secondary contaminations. Photocatalysis on semiconductor photocatalysts has exhibited efficacy in decomposing a wide variety of organic compounds into less poisonous organic mixtures or biodegradable compounds, along with inorganic H2O, PO43−, CO2, NO3−, and halide ions. Therefore, Dy2Cu2O5 nanostructures have been synthesized through the uncomplicated and affordable sonochemical approach. The effect of sonication power and time was investigated on the particle size, morphology, and shape of products. Dy2Cu2O5 nanostructures possess a suitable bandgap (3.2 eV) in the UV area. The photocatalytic ability of Dy2Cu2O5 was surveyed for the elimination of various organic colorants below UV and visible radiation and exposed that this compound could decolorize and remove 96.4 % of phenol red. Moreover, the possible reaction rate coefficient (k) of dyes was determined relying on the Langmuir–Hinshelwood reaction, showing that maximum photocatalytic performance was achieved in a larger reaction rate constant (k = 0.029 min−1).

Effects of sonication power on electrochemical performance of ZrO2-decorated LiMn2O4 cathode material for LIBs

The LiMn2O4 (LMO) powder is decorated with ZrO2 (denoted as Zr@LMO) particles by using sonication-assisted sol–gel method. Different sonication powers (10, 30 and 50%) are used to disperse ZrO2 and the effects of ZrO2 distribution at LiMn2O4’s electrochemical performance are analysed. Scanning electron microscopy and energy dispersive spectroscopy analyses have been made on laminated samples. For the structural analyses of particles, X-ray diffractometer is used. Electrochemical performances of electrodes are tested with galvanostatic measurements, cyclic voltammograms and electrochemical impedance spectroscopy. The ZrO2 distribution ratio on the particle surfaces is improved by 10% with the increase of sonication power from 10 to 50%. Therefore, at 50% sonication power, lower charge transfer resistance and side reactions (Mn dissolution) are accomplished, which leads to 41 and 9% specific capacity increase compared to pure and the lowest sonication power, respectively. After 100 cycles at 0.1C, 93.2 mAh g–1 specific discharge capacity and 73.4% capacity retention are attained for ZrO2-decorated LMO at 50% sonication power. Furthermore, at 2C rate, the specific discharge capacity of the decorated sample at 50% sonication power is 59% higher than the pure LMO.

Green sonochemical synthesis of BaDy2NiO5/Dy2O3 and BaDy2NiO5/NiO nanocomposites in the presence of core almond as a capping agent and their application as photocatalysts for the removal of organic dyes in water.

The present work reports the sonochemical synthesis of DBNO NC (dysprosium nickelate nanocomposite) using metal nitrates and core almond as a capping agent. In addition, the effects of the power of ultrasound irradiation were investigated. The BaDy2NiO5/Dy2O3 and BaDy2NiO5/NiO nanocomposites were synthesized with sonication powers of 50 and 30 W, respectively. The agglomerated nanoparticles were obtained using different sonication powers, including 15, 30, and 50 W. The results showed that upon increasing the sonication power, the particle size decreased. After characterization, the optical, electrical, magnetic, and photocatalytic properties of the NC were studied. The nanocomposites showed an antiferromagnetic behavior. In this study, the photocatalytic degradations of two dyes, AR14 and AB92, were investigated in the presence of DBNO NC. Furthermore, the effects of the amount of photocatalyst, the concentration of the dye solution, the type of organic dye, and light irradiation on the photocatalytic activity of the nanocomposite were studied. The results showed that with an increasing amount of catalyst and decreasing concentration of dye, the photocatalytic activity of the nanocomposite was increased. This activity for the degradation of AR14 is higher than that of AB92. Both AR14 and AB92 dyes show higher photocatalytic degradation under UV irradiation than under Vis irradiation.

Effect of Sonication on the Properties of Flaxseed Gum Films Incorporated with Carvacrol.

Carvacrol is a natural compound known to be a highly effective antibacterial; however, it is a hydrophobic molecule, which is a limitation to its use within food packaging. Flaxseed gum (FG) films containing different contents of carvacrol (C) were produced by a film-casting method with sonication. The effects of sonication power and time on the properties of the FG-C films were investigated by measuring the film thickness, mechanical properties, contact angle, opacity, water vapor permeability (WVP), water sorption isotherm, Fourier transform infrared spectroscopy(FTIR), differential scanning calorimetry (DSC), antibacterial and antioxidant activities, and microstructure. The results showed that sonication power and time had significant effects on mechanical and barrier properties, film opacity, and degradability (p < 0.05). The tensile strength (TS) and elongation at break (EB) values exhibited an obvious improvement after sonication, and FG-0.5C-6030 had the lowest TS (33.40 MPa) and EB (4.46%) values. FG-C films formed a denser structure and the contact angle was improved as a result of sonication, which improved the integration of carvacrol into the FG matrix. In terms of microstructure, sonication resulted in a homogeneous and continuous crosssection of FG-C films, and regular surface and cross-sectional images were obtained through the highest acoustic intensity and longest time treatment. The FG films incorporated with carvacrol displayed antibacterial properties against Staphylococcus aureus, Vibrio parahaemolyticus, Shewanella putrefaciens, and Pseudomonas fluorescens, as well as increased antioxidant properties, and sonication was proven to enhance both of them.

Sonochemical synthesis and characterization of four nanostructural nickel coordination polymers and photocatalytic degradation of methylene blue

Four nanostructural nickel(II) coordination polymers {[Ni(ttpa)(1,4-ndc)(H2O)2]·2H2O}n (1), {[Ni(ttpa)(1,3-bda)]·2H2O·DMF}n (2·2H2O·DMF), {[Ni(ttpa)(1,4-bdc)]·H2O}n (3) and {[Ni(ttpa)(aip)(H2O)]·3H2O}n (4·3H2O) were synthesized using hydrothermal and sonochemical methods (ttpa = tris(4-(1,2,4-triazol-1-yl)phenyl)amine, 1,4-ndc = 1,4-naphthalenedicarboxylate, 1,3-bda = 1,3-benzenediacetate, 1,4-bdc = 1,4-benzenedicarboxylate, aip = 5-aminoisophthalate), and characterized by elemental analysis, IR spectra, scanning electron microscopy, single-crystal and powder X-ray diffraction analysis, optical band gaps, VB XPS spectra and luminescence. The effects of sonication power, time and frequency on the size and morphology of nano-sized 1–4 have been studied. 1 exhibits an unusual 2D + 2D → 3D inclined polycatenated motif based on the (3,3)-coordinated 63-hcb topology. 2 shows a (3,4)-coordinated 2D network of the bey topology. 3 presents a rare example of the 4-fold interpenetrating array of (3,5)-coordinated 3D network belonging to the 35T1 topology type. 4 displays an unusual 2D → 3D polythreaded network based on 2D sql networks. 1–4 exhibit luminescent emissions at 409, 399, 413 and 402 nm, respectively. 1–4 are semiconducting in nature, with Eg of 2.12 eV (1), 2.34 eV (2), 2.32 eV (3), and 2.47 eV (4). 1–4 are good catalysts for the degradation of MB under visible light irradiation. The effects of the size and morphology of nano-sized 1–4 on the photocatalytic efficiencies were studied. The higher sonication frequency obtains uniform and smaller nano-sized coordination polymers which have higher catalytic efficiencies.

Effect of sonication power on perfusion decellularization of cadaveric porcine kidney

Kidney problems rank 7th among the top 10 causes of mortality among Filipinos. One of the potential future treatment options is the use of bioengineered kidney. The preparation of scaffolds is the first step in kidney bioengineering and perfusion decellularization using chemicals is considered the most preferred preparation method to date. However, the use of chemicals alone requires long treatment time hence, in this study perfusion decellularization is to be enhanced by sonication treatment at varying sonication power. Decellularization was carried out by perfusing the kidney with 1% SDS and was subjected to sonication treatment with a 2h sonication and 2h rest cycle. The cycle is repeated until the kidney is clear and transparent. Washing using 1% Triton X-100 and 1x PBS then follows to remove residual SDS. The extent of cell removal was determined by H&amp;E staining. The results showed that decellularization with sonication using 150W, 200W and 250W required a treatment time of 24h, 16h and 12h respectively compared to the 28h treatment time of decellularization without sonication. The result clearly shows that with higher sonication power, the shorter is the decellularization time needed to prepare a good kidney scaffold.

Improved rheological properties and stability of multiwalled carbon nanotubes/polymer in harsh environment

ABSTRACTThis work aims to improve the rheological properties and stability of multiwalled carbon nanotubes (MWCNTs)/acrylamide (AA) base skeleton polymer blends at harsh environment of high salinity‐high temperature (HS‐HT) or various pH. Different co/terpolymers have been accomplished to modify the structure of AA polymer by free‐radical copolymerization of AA‐based monomers. Anionic, cationic, and hydrophobic functional groups were used for the synthesis of polyelectrolyte, polyampholytic, and partially hydrophobic AA polymer types. The conversion, molecular weight, and poly dispersity of co/terpolymers have been evaluated by nuclear magnetic resonance (1H‐NMR), gel permeation chromatography, and differential scanning calorimetry analysis. The effects of sonication power, concentration of polymer, and concentration of MWCNTs were also investigated on rheological behavior of co/terpolymers. The results show that negative polyelectrolyte and polyampholytic polymers are the best candidates for the improvement of MWCNTs/polymer stability and viscosity at HS‐HT and alkali environment, respectively. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47205.

Energy-efficient ultrasonic release of bacteria and particulates to facilitate ingestion by phagotrophic algae for waste sludge treatment and algal biomass and lipid production

Wastewater treatment generates large amounts of waste activated sludge (WAS) that contains concentrated bacteria and particulate organics and requires costly treatment prior to disposal. This study develops an approach to harness the unique capability of oleaginous phagotrophic microalgae for treating WAS and producing algal biomass and lipids. WAS ultrasonication is studied for releasing particulates and bacteria suitable for direct ingestion by phagotrophic microalgae, without bacterial destruction/lysis, and thus minimizing energy requirement. Particle release into supernatant was followed by optical density at 610 nm (OD610) and volatile solid concentration (VS); OD610 correlated well with micron-size particle count rates measured by dynamic light scattering. Microalgae (Ochromonas danica) grew with a 7.6-h doubling time in sonication-generated WAS supernatant alone, giving approximately 66% (w/w) cell yield from consumed VS and ∼30% intracellular lipids. Effects of sonication power (P in W), WAS volume (V in mL) and sonication duration (t in s) were studied with a 3 × 3 × 6 factorial design. Supernatant OD610 increased with increasing P and t and decreasing V. Multiple linear regression gave the following equation with only significant terms: OD610TS=−0.0536+0.000592P−0.000213t+0.000003P×t+0.000274P×tV (R2 = 0.94). Sonicating 500-mL WAS at 180 W for 240 s was selected for giving high particulate release (∼29% VS) with maximal energy efficiency, corresponding to a specific energy input of 4320 kJ (kg TS)−1, which was much lower than the range (15,000–250,000 kJ (kg TS)−1) reported previously for WAS ultrasonication. The results supported development of new ultrasonication-phagotrophic algae processes for WAS treatment and algae production.

Ultrasonication-Assisted Hydrothermal Synthesis of Ultralong TiO2 Nanotubes

Abstract Ultralong titanate nanotubes were synthesized by treating general anatase TiO2 in alkaline solution using a facile sonication-assisted hydrothermal method. The as-synthesized products via sonication and sonication-hydrothermal treatment were characterized by SEM, TEM, OM and XRD. The effects of sonication power, sonication frequency and sonication temperature on the morphology and the crystal structure of the products were investigated. The results show that in the range of ultrasonic power (200, 300, 400, 500 W) and frequency (20, 40, 80 kHz), titanium dioxide particles were swelled in alkali aqueous solution to get the hedgehog flocculent intermediate products by ultrasonic irradiation when the ultrasonic temperature was equal or higher than 60 °C; several tens of microns long titanate nanotubes were achieved using the intermediate products as raw materials under the mild hydrothermal conditions of 90 °C and 5 h. The possible formation mechanism for ultralong titanate nanotubes was also discussed. The hedgehog floccules synthesized by sonication play an important role to synthesize the several tens of micrometers long nanotubes.

Experimental investigations on ultrasound mediated particle breakage

This paper investigates the effect of high-intensity ultrasound on the breakage characteristics of particles suspended in water. A continuous sonicated flow experimental apparatus is used involving a 24 kHz horn type transducer and continuous in-line particle chord length measurement. The effects of sonication power (150–350 W) and temperature (10–50 °C) on the breakage characteristics are investigated. Higher breakage is favored at higher sonication power. An optimum temperature in the range tested is observed to exist between 25 °C and 37 °C. The acoustic cavitation field is influenced by temperature through a complex interplay of vapor pressure, surface tension and viscosity leading to the optimum observed in particle breakage. The efficiency of ultrasound energy conversion to particle breakage is calculated using calorimetry and found along with the net breakage efficiency to initially increase with temperature followed by a decrease after the optimum. It is found to be independent of input ultrasonic power. The effects of contact time is also investigated.

Graphitic Carbon Nanofiber (GCNF)/Polymer Materials. I. GCNF/Epoxy Monoliths Using Hexanediamine Linker Molecules

Processing methods have been optimized for the formation of graphitic carbon nanofiber (GCNF)/epoxy nanocomposites containing GCNFs highly dispersed throughout a thermoset epoxy matrix. GCNFs having a herringbone atomic structure are surface-derivatized with bifunctional hexanediamine linker molecules (GCNF-HDA) capable of covalent binding to an epoxy matrix during thermal curing and are cut to smaller dimension using high-power ultrasonication. GCNF-HDA nanofibers are dispersed in epoxy resin at 0.3 wt.% loading using variable levels of ultrasonication processing prior to thermal curing. Effects of sonication power on the quality of the GCNF-HDA/epoxy material obtained after curing have been determined from flexural property measurements, thermomechanical analysis and SEM/TEM imaging. GCNF-HDA/epoxy material of the highest quality is obtained using low-power sonication, although high-power sonication for short periods gives improved flexural properties without lowering the glass transition temperature. Good dispersion and polymer wetting of the GCNF component is evident on the nanoscale.

Sono-electrochemical Determination of Uric Acid

Determination of uric acid by electrochemical method using ultrasonic stimulation has been investigated. Effects of sonication power, sonication time, pH of the solution and temperature were studied to obtain the optimal analytical conditions. The stability of the electrode was also examined. The optimal conditions for the sonovoltammetric determination of uric acid were as follows: temperature, pH 7.0; sonication power, . The calibration curve for the determination of uric acid by sono-LSV was linear over the range of and the limit of detection was .