Effect Of Ultrasonic Irradiation Research Articles

Effects of ultrasonic irradiation on organic matter of Microcystis aeruginosa cells

Effects of ultrasonic irradiation on organic matter of Microcystis aeruginosa cells

Enhancing Biodiesel from Kemiri Sunan Oil Manufacturing using Ultrasonics

Kemiri Sunan (Reutalis trisperma (Blanco) Airy Shaw) is a potential plant to be developed as biodiesel feedstock. The advantage of Kemiri Sunan seeds when compared to other biodiesel raw materials is their high oil content. This plant is also very good for land conservation. Due the increasingly demand for biodiesel, research and new methods to increase its biodiesel production continue to be undertaken. The weakness of conventional biodiesel manufacturing process is in the mixing process in which mechanical stirring and heating in the trans-esterification process require more energy and a longer time. A higher and stronger mixing process is required to increase the contact area between the two phases of the mixed substance to produce the emulsion. Ultrasonic is a tool that can be useful for a liquid mixing process that tends to be separated. Ultrasonic waves can cause mixing intensity at the micro level and increase mass transfer, so the reaction can be performed at a much faster rate. This study is to figure out the effect of ultrasonic irradiation on the transesterification process of biodiesel from Kemiri Sunan Oil.

Effect of sonochemical scouring on the surface morphologies, mechanical properties, and dyeing abilities of wool fibres

Ultrasonics has the potential to reduce the cost and environmental impact of textile processing. This work investigates the effects of ultrasonic irradiation during wool scouring on fibre surface morphologies, fibre mechanical properties, and fibre dyeing abilities. A range of ultrasonic frequencies were used in the scouring bath to examine the forms of fibre cuticle damage. It is observed that wool fibres underwent ultrasonic irradiation at a low frequency have severe modifications of the fibre surface structure. Despite some visible disruptions to the fibre scale structure however, ultrasonic irradiation has shown a negligible impact on the fibre mechanical properties, especially bending abrasion resistance which depends largely on the fibre surface conditions, and is responsible for the handle and pilling propensity of the resultant fabrics. Dyeing abilities were investigated on wool samples using commercially available acid dye and reactive dye. It is found that ultrasonically scoured wool has a quicker dye uptake in the early stage of low temperature dyeing for both acid dye and reactive dye, than the conventionally scoured wool.

ZnO/ZrO2 nanocomposite: Sonosynthesis, characterization and its application for wastewater treatment

ZnO/ZrO2 nanocomposites with different ZnO: ZrO2 molar ratios (2:1, 1:1, and 1:2)were prepared by sol gel approach under ultrasonic irradiation. For preparation of the nano-composites, the ZnO gel was directly incorporated into the ZrO2 gel at different molar ratios. The reaction mixture was stirred continuously for two days and then it was ultrasonoicated for 30min. The filtrated composite gel was washed, and then calcinated at 300°C in furnace for 3h. X-ray powder diffraction patterns exhibited well-formed crystal structures and pure crystalline phases in the synthesized nanoparticles (NPs). The FT-IR analyses indicated that the positions of peaks related to Zn-O and Zr-O absorption bands did not change in nano-composites. In addition, FESEM images indicated uniform spherical morphology of the NPs. The highest photo-degradation performance of Congo red (as a model water pollutant) was obtained by 1:2molar ratio of ZrO2: ZnO in the nano-composite. The particle size and band gap were considered as important factors on nano-catalysts performance. Furthermore, the effects of ultrasonic irradiation, pH, and the concentration of pollutant in solution were investigated on photocatalytic performance of optimum nanocomposite.

Effect of ultrasonic irradiation on bacterial biofilms.

The purpose of this study was to clarify the effect of ultrasonic irradiation on biofilm produced by Staphylococcus epidermidis (S. epidermidis), which causes central venous catheter-related infections. Staphylococcus epidermidis (S. epidermidis, ATCC 35984 RP 62A) was used in this study. First, biofilm was prepared from S. epidermidis on the bottom of the upper left well of a 6-well plate. Next, the biofilm was irradiated for 24h with 1-MHz ultrasound (US) in the continuous wave mode to serve as the US irradiation group. The acoustic power irradiated below the bottom of the well was 3.8 mW. As a control (non-US irradiation group), non-irradiated biofilm on the bottom of a 6-well plate was incubated at 37°C in an atmosphere of 5.0% CO2. After US irradiation, the bottoms of the wells were stained with 0.1% crystal violet for 60s. To extract the crystal violet, 99.5% ethanol was added to the wells, and the extracted solutions were measured at an absorbance of 595nm. The absorbance of the US irradiation group was significantly less than that of the non-US irradiation group (p<0.01). US irradiation can decrease the amount of S. epidermidis biofilm when the duration of US irradiation is sufficiently long even if the acoustic intensity is low.

Chemical coloring on stainless steel by ultrasonic irradiation

To solve the problems of high temperature and non-uniformity of coloring on stainless steel, a new chemical coloring process, applying ultrasonic irradiation to the traditional chemical coloring process, was developed in this paper. The effects of ultrasonic frequency and power density (sound intensity) on chemical coloring on stainless steel were studied. The uniformity of morphology and colors was observed with the help of polarizing microscope and scanning electron microscopy (SEM), and the surface compositions were characterized by X-ray photoelectric spectroscopy (XPS), meanwhile, the wear resistance and the corrosion resistance were investigated, and the effect mechanism of ultrasonic irradiation on chemical coloring was discussed. These results show that in the process of chemical coloring on stainless steel by ultrasonic irradiation, the film composition is the same as the traditional chemical coloring, and this method can significantly enhance the uniformity, the wear and corrosion resistances of the color film and accelerate the coloring rate which makes the coloring temperature reduced to 40°C. The effects of ultrasonic irradiation on the chemical coloring can be attributed to the coloring rate accelerated and the coloring temperature reduced by thermal-effect, the uniformity of coloring film improved by dispersion-effect, and the wear and corrosion resistances of coloring film enhanced by cavitation-effect. Ultrasonic irradiation not only has an extensive application prospect for chemical coloring on stainless steel but also provides an valuable reference for other chemical coloring.

P13 銀ナノ粒子合成における超音波照射の影響(ポスターセッション)

P13 銀ナノ粒子合成における超音波照射の影響(ポスターセッション)

P7 希硫酸を用いたセルロース系バイオマスの加水分解における超音波照射と物理的前処理の効果(ポスターセッション)

P7 希硫酸を用いたセルロース系バイオマスの加水分解における超音波照射と物理的前処理の効果(ポスターセッション)

Controlling dispersion of graphene nanoplatelets in aqueous solution by ultrasonic technique

The homogenous graphene nanoplatelets (GNP) suspension had been prepared through ultrasonic exfoliation in the presence of methylcellulose (MC) as dispersant. The influence of different sonication times on dispersing of aqueous GNP suspension was monitored by UV–Vis absorbance, sedimentation test, optical microscope and transmission electron microscope (TEM). The study of UV–Vis absorbance verifies that the minimum sonication time to break the 0.1 g/L concentration of bundled GNPs is 20 min; furthermore, the GNP suspension achieved the best dispersion, when sonication time increased up to 80 min. From optical microscope images of GNPs, the agglomeration of GNPs was broken by enough sonication energy, and the distribution of GNPs particles became more uniform. The dispersing mechanism had been discussed and simulated by HRTEM image. The bundled GNPs were exfoliated by cavitation effect of ultrasonic irradiation, meanwhile, the dispersant adsorbed on the surface of GNPs prevented re-entanglement by forming steric hindrance.

Terbium–organic framework as heterogeneous Lewis acid catalyst for β‐aminoalcohol synthesis: Efficient, reusable and green catalytic method

A terbium–organic framework (Tb‐MOF) was prepared using a previously reported procedure. Tb‐MOF was characterized using Fourier transform infrared spectroscopy, scanning electron microscopy, powder X‐ray diffraction and surface area analysis. Tb‐MOF was employed as a heterogeneous Lewis acid catalyst for the synthesis of β‐aminoalcohols. Also, the effect of ultrasonic irradiation was examined in the catalytic aminolysis of styrene oxide. The reaction conditions were optimized by variation of reaction time, catalyst concentration and solvent. A variety of β‐aminoalcohols were synthesized and characterized. The Tb‐MOF catalyst showed excellent selectivity and high yield for these transformations.

The effect of ultrasonic irradiation on the structure, morphology and photocatalytic performance of ZnO nanoparticles by sol-gel method

In this research, the effect of ultrasonic irradiation power (0, 75, 150 and 200W) and time (0, 5, 15 and 20min) on the structure, morphology and photocatalytic activity of zinc oxide nanoparticles synthesized by sol-gel method was investigated. Crystallographic structures and the morphologies of the resultant powders were determined by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The XRD patterns showed that ZnO samples were crystallized in their pure phase. The purity of samples was increased by increasing the ultrasonic irradiation power and time. Not only did ultrasonic irradiation unify both the structure and the morphology, but also it reduced the size and prohibited particles from aggregation. The optical behavior of the samples was studied by UV–vis spectroscopy. Photocatalytic activity of particles was measured by degradation of methyl orange under radiation of ultraviolet light. Ultrasound nanoparticles represented higher degradation compared to non-ultrasound ones.

A Study on the Effects of Ultrasonic Irradiation as Pretreatment Method on High-Ash Coal Flotation and Kinetics

ABSTRACTThis research work was undertaken to assess effect of ultrasonic irradiation as a pretreatment method for high-ash coal flotation and its kinetics. Ultrasonic treatment was applied prior to flotation at different ultrasonic power levels and periods. Feed samples containing 50.29% ash and 1.10% sulfur were acquired from the Tabas coal mine located in Yazd province, Iran. Flotation experiments were conducted based on a two-level fractional factorial design with six variables: ultrasound intensity, collector dosage, conditioning time, pH, rotor speed, and solid content. The collected data were analyzed by DX7.0 software to evaluate the effect of each parameter on the optimization criteria. Considering the highest combustible recovery and the lowest ash and sulfur contents, value of optimized parameters were as follows: ultrasound intensity, 30 W/cm2; 1500 g/t collector, 11 min of conditioning time, pH = 7.5, 800 rev/min of rotor speed, and 10% solid content. Under these conditions, 56.9% combustible recovery and 9.21% ash content of product were obtained. Finally, the kinetic flotation experiments were conducted using the optimized level of parameters in first stage. It was observed that coal flotation on an average was 10% faster using ultrasonic conditioning in comparison with the conventional conditioning. Flotation of high-ash coal with ultrasound pretreatment could be described almost with the fully mixed, second-order models.

Effect of ultrasound on the interaction between (−)-epicatechin gallate and bovine serum albumin in a model wine

Ultrasound is considered as a potential novel technique for improving the quality of some wines. In this paper, a model wine firstly was constructed with the standards of (−)-epicatechin gallate (ECG) and bovine serum albumin (BSA) as target compounds. Then, the experiments were conducted to investigate the effect of ultrasonic irradiation on the binding properties between ECG and BSA including quenching mechanism, binding parameters, binding forces, energy transfer distance and conformational changes determined by spectral analysis. The results indicate that ultrasound definitely has some regular effects on the binding interaction of BSA and ECG, and can induced the conformation variation of BSA in the simulated wine, which may suggest that the ultrasound might be employed to modify the wine organoleptic property by regulating the interaction between phenolic compounds and proteins from the autolysis of yeasts, since they are similar to the standards of ECG and BSA, respectively.

The Effect of Preparation Conditions on the Removal Efficiency of Water Pollutants Using LTA Zeolite

In this study LTA zeolite was prepared from kaolin. The effect of ultrasonic irradiation on the crystal structure and ability to ion exchange of some heavy metals were studied. Many techniques were used to characterize the prepared zeolite includes X-ray diffraction analysis (XRD) with crystal lattice analysis, Electron paramagnetic resonance (EPR) and finally ion exchange isotherm of some heavy metal ions. The results showed that the ultrasonicated zeolite exhibits different behavior towards ion exchange with increasing its capacity. The ultrasonicated zeolite showed little increase in the lattice parameters with increasing in the crystal size. Fitting adsorption isotherms on the metal adsorbed showed an observable change in the behavior of ultrasonicated zeolite towards the metals exchanged.

Investigation on the Effects of Ultrasonic Irradiation and Sodium Hydroxide on Decomposition of Cellulose Using RF Plasma in Liquid for Hydrogen Production at Atmospheric Pressure

Investigation on the Effects of Ultrasonic Irradiation and Sodium Hydroxide on Decomposition of Cellulose Using RF Plasma in Liquid for Hydrogen Production at Atmospheric Pressure

Experimental study on the influence of low-frequency and low-intensity ultrasound on the permeability of the Mycobacterium smegmatis cytoderm and potentiation with levofloxacin

Tuberculosis is an infectious disease caused by the bacterium M. tuberculosis. The aim of this study was to investigate the bactericidal effect and underlying mechanisms of low-frequency and low-intensity ultrasound combined with levofloxacin treatment against M. smegmatis (a surrogate of M. tuberculosis). As part of this study, M. smegmatis was continuously irradiated with low frequency ultrasound (42kHz) using several different doses whereby both intensity (0.138, 0.190 and 0.329W/cm2) and exposure time (5, 15 and 20min) were varied. Flow cytometric analyses revealed that the permeability of M. smegmatis increased following ultrasound exposure. The survival rate, structure and morphology of bacteria in the lower-dose (ISATA=0.138W/cm2 for 5min) ultrasound group displayed no significant differences upon comparison with the untreated group. However, the survival rate of bacteria was significantly reduced and the bacterial structure was damaged in the higher-dose (ISATA=0.329W/cm2 for 20min) ultrasound group. Ultrasound irradiation (0.138W/cm2) was subsequently applied to M. smegmatis in combination with levofloxacin treatment for 5min. The results demonstrated that the bactericidal effect of ultrasonic irradiation combined with levofloxacin is higher compared to ultrasound alone or levofloxacin alone.

Oxidative Desulfurization of Model Diesel Using Ionic Liquid 1-Octyl-3-methylimidazolium Hydrogen Sulfate: An Investigation of the Ultrasonic Irradiation Effect on Performance

A Bronsted acidic ionic liquid (IL), 1-octyl-3-methylimidazolium hydrogen sulfate ([Omim][HSO4]), was prepared and utilized as the extractant and catalyst to study the oxidative desulfurization of dibenzothiophene (DBT) in n-decane as the model oil. The effects of the alkyl chain length of the IL cation, temperature, H2O2/DBT molar ratio (O/S), IL/oil mass ratio, initial S-content, and sulfur species on the sulfur removal of the model oil were investigated. Complete removal of DBT was observed by [Omim][HSO4], O/S molar ratio of 5, and IL/oil mass ratio of 1:2 after 70 min at 25 °C. The order of observed oxidizing reactivity for different sulfur species was as follows: DBT > benzothiophene (BT) > thiophene (TH) > 4,6-dimethyldibenzothiophene (4,6-DMDBT). The IL could be reused six times without a significant decrease in the desulfurization activity. The kinetics of oxidative desulfurization for DBT by [Omim][HSO4] was found to be pseudo-first-order with an apparent rate constant of 0.0734 min–1 (at 298 K)...

A survey on the effects of ultrasonic irradiation, reaction time and concentration of initial reagents on formation of kinetically or thermodynamically stable copper(I) metal-organic nanomaterials

In order to evaluation the effects of ultrasonic irradiations, concentration of initial reagents and reaction time on formation [Cu4(MBT)4] or [Cu6(MBT)6] copper(I) metal-organic nanomaterials, [HMBT=2-Mercaptobenzothiazole], we designed some experiments and synthesized six samples under different conditions. These nanostructures were characterized by IR spectroscopy, X-ray powder diffraction (XRD) and Scanning Electron Microscopy (SEM). It seems that the tetranuclear cluster of [Cu4(MBT)4] (2) is the kinetically stable product which is formed at the initial time of the reaction and as the time went, it converts to thermodynamically stable product of [Cu6(MBT)6] (1) with hexanuclear cluster unit. In the samples which synthesized with low concentration of initial reagents, against to those synthesized with high concentration of initial reagents, the ultrasonic irradiation does not have any effect on formation of any special morphology.

Wear-Resistant Polymer Composites Based On Polytetrafluoroethylene And Layered Silicates

&lt;p&gt;To improve interaction on the phase boundary of polymer composites, we used functional additives, mechanoactivation method, and ultrasound. In the case of the use of serpentine as a modifier of polytetrafluoroethylene (PTFE), the introduction of magnesium nanospinel (NS) as functional additive resulted in the increase of wear resistance of composite in 2500 times. Effect of ultrasonic irradiation on the composites comprising phlogopite was considered. IR data have shown that NS influences the intensification of the tribological processes. In sonicated composites the intensity of the IR spectra of oxidized fragments depends on the content of NS and correlates with the wear resistance.&lt;/p&gt;

Studies the effects of ultrasonic irradiation and dielectric constants of solvents on formation of lead(II) supramolecular polymer; new precursors for synthesis of lead(II) oxide nanoparticles

In order to evaluation the effects of ultrasonic irradiations and dielectric constants of solvents on formation [Pb2(5-Clq-8-ol)2(OAc)2]n (1), [H5-Clq-8-ol=5-chloroquinolin-8-ol and OAc-=acetate], we designed some experiments and synthesized six samples of 1 under different conditions. Microrods of a lead(II) supramolecular polymer, were synthesized under these conditions. These microstructures were characterized by IR spectroscopy, X-ray powder diffraction (XRD) and Scanning Electron Microscopy (SEM). The results indicated that compound 1 with the best crystallinity can be obtained in the presence of MeCN and H2O (as the bulk sample) and in the presence of MeCN and EtOH (by sonochemical process). The least agglomeration of microrods was observed in H2O which is due to high dielectric constant of it. By considering all of the factors consist of crystallinity and agglomeration of the products and their corresponding histograms, it seems that MeCN is the best solvent for synthesis of 1. The samples which were synthesized in the presence of MeCN, had been used as new precursors for fabricating lead(II) oxide nanoparticles via thermal decomposition in oleic acid (OA).