• Journal of the Korean Ceramic Society
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• v.36 no.7
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• pp.751-755
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• 1999

Effect of ultrasonic-wave irradiation on the Mn-Zn ferrite powder suspension prepared by solid-state reaction and alcoholic dehydration methods was investigated. Size distribution and morphology of the powders prepared at different temperature were examined as a function of irradiation time. It was observed that the powders were reduced in size by ultrasonic energy through distinct routes.

• Journal of Soil and Groundwater Environment
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• v.19 no.6
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• pp.72-79
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• 2014

Cavitation generated by ultrasonic irradiation can enhance the diffusional transport of organic contaminants from soil surfaces or pores. Therefore, ultrasound soil washing can be an alternative of traditional soil washing process. In this study, soil was artificially contaminated with n-tetradecane, n-hexadecane and phenanthrene. A plate type ultrasonic reactor at 25 kHz frequency and 1000W power was used for laboratory soil washing experiments. Ultrasonic soil washing efficiency was compared with those of traditional soil washing using mechanical mixing. Various operational parameter such as soil/liquid ratio, irradiation time, particle size, and soil organic matter content was tested to find out the optimum condition. It was found that ultrasonic soil washing demonstrates better performance than mechanical soil washing. Optimum soil:liquid ratio for ultrasonic soil washing was 1 : 5. Desorption of organic contaminants from soils by ultrasonic irradiation was relatively fast and reached equilibrium within 10 minute. However, decrease in the soil particle sizes by ultrasonic irradiation results in re-adsorption of contaminants to soil phase. It was also observed that soil particle size distribution and soil organic matter content have significant effects on the efficiency of ultrasonic soil washing.

• Journal of the Korean institute of surface engineering
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• v.20 no.1
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• pp.4-14
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• 1987

The nickel-zinc alloy depositions have been studied in nickel chloride added chloride baths, to find out the effects of ultrasonic irradiation for the electrodeposition processes. The compositions of deposited alloys, the current efficiencies and the metallographic appearances in various conditions of Electrodeposition were investigated, in the range of ultrasonic irradiation of 50,500 and 1,000 Kc/s respectively. The results obtained are as follows; 1. Generally the nickel deposition process is more preferably activated than that of zinc by the ultrasonic irradiation. 2. The radios of nickel to zinc in the deposit are higher according to increase of nickel ion concentration and bath temperatures in irradiated baths. 3. The current efficiencies are also higher in the irradiated baths, so that the depolarization effect is noticeable. 4. The brightness and leveling effect of the deposits are appreciably better in the irradiated baths than in non-irradiated in 0.3M and 0.6M of nickel chloride and zinc chloride solutions and the current density of 3A/$dm^2$. 5. The mechanism of alloy deposition has been tentatively suggested in the case of ultrasonic irradiation.

• Journal of Energy Engineering
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• v.13 no.4
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• pp.235-241
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• 2004

This experiment was undertaken to investigate the atomization characteristics of the high viscosity biodiesel blended fuel and ultrasonic energy irradiation one. Test fuels were conventional diesel fuel and biodiesel one. We compared to the characteristics of viscosity and surface tension, SMD between high viscosity biodiesel blended fuel and ultrasonic energy irradiation one. Sauter mean diameter was measured under the variation of the spray distance. Viscosity and surface tension were measured under the variation of the time trace. To measure the droplet size, we used the Malvern system 2600c. Droplet size distribution was analyzed from the result data of Malvern system. Through this experiment, we found that the condition of the ultrasonic energy irradiation situation had smaller Sauter mean diameter of droplet, viscosity and surface tension than those of the conventional situation.

• Applied Chemistry for Engineering
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• v.29 no.5
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• pp.503-509
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• 2018

In this study, we used the ultrasonic extraction process as a method to extract antioxidant substances from kudzu, and measured the content of iso-flavonoids puerarin, daidzein, daidzin contained in kudzu. The response surface methodology which is a statistical analysis method for optimizing the extraction amount of iso-flavonoids from the kudzu and the process condition for maximizing the yield was applied. It is the final objective of this study to effectively derive the condition of the process that matches the target response with a minimum number of experiments and analyze the effect of each process condition on the response. In the response surface methodology, the central composite design was applied and the optimum condition was analyzed, and the three independent variables were set to ultrasonic irradiation time, volume ratio of ethanol/ultrapure water, ultrasonic irradiation power. Using the response surface methodology, the optimum conditions with the maximum extraction yield and the content of iso-flavonoids were evaluated as ultrasonic irradiation time (24.75 min), ethanol / ultrapure water volume ratio (39.75 vol%), ultrasonic irradiation power (592.36 W). The overall satisfaction level appears as high as 0.8938, which is recognized at a significance level within 5%. As a result of analyzing the optimization process, it was confirmed that the ultrasonic irradiation time is the factor that most affects the responses.

• Journal of the Korean Society of Marine Environment & Safety
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• v.7 no.3
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• pp.75-84
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• 2001

Ultrasonic vibrator is an equipment which atomizes and homogenizes the oils by breaking the oil particles with ultrasonic vibration cavity, and possibly improves the properties. There are various parameters on the effect of ultrasonic irradiation. Especially, this study intended to investigate the matrix structure of sludge oils and the erosion damages for horn disc SS41 according to the variation of the oil temperature and the immersing depth of horn disc. Sludge oils were irradiated with ultrasonic vibration and then observed the aspects of the change of oil particles. From these, the recycling feasibility of sludge oil for useable oil to be burnt was determined. The erosion damages for horn disc SS41 were examined with weight loss, weight loss rate and the irradiation time to max. erosion rate. These data will be useful to the development of ultrasonic breaking systems to recycle sludge oil and to consider a countermeasure for the prevention of erosion damages.

• Journal of the Korean Ceramic Society
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• v.39 no.2
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• pp.113-119
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• 2002

The effect of ultrasonic radiation is reported for silica-poly(ethylene glycol) system prepared without the solvent using sol-gel processing by varying various parameters such as ultrasonic irradiation time, PEG content and HCl/TEOS molar ratio. The property of sonogel is compared with classic gel which has been prepared with ethanol as a solvent by traditional sol-gel processing. SEM, BET, DTA-TGA, density and Vickers hardness measurements are carried out for analyzing the samples. The gelation time is found strongly dependent on radiation time, PEG content and pH value, and has been discussed on the basis of existing theories. The $SiO_2-10$ & 20 wt% PEG sonogel exhibited superior optical, physical and gel properties as compared to the classic gel, hence, found suitable for device applications. The ultrasonic radiation increased the density and surface area, and also reduced the pore size which is well supported by the shift in the peak of DTA curve. The DTA thermogram was found similar to that of pure silica gel.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.9
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• pp.25-31
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• 2020

In this study, for the safe use of a portable ultrasonic skin-beauty device, an android app was developed to show the irradiation locations of focused ultrasound to a user through augmented reality (AR) and enable stable self-surgery. The utility of the app was assessed through testing. While the user is making a facial treatment with the beauty device, the user's face and the ultrasonic irradiation location on the face are detected in real-time with a smart-phone camera. The irradiation location is then indicated on the face image and shown to the user so that excessive ultrasound is not irradiated to the same area during treatment. To this end, ML-Kit is used to detect the user's face landmarks in real-time, and they are compared with a reference face model to estimate the pose of the face, such as rotation and movement. After mounting a LED on the ultrasonic irradiation part of the device and operating the LED during irradiation, the LED light was searched to find the position of the ultrasonic irradiation on the smart-phone screen, and the irradiation position was registered and displayed on the face image based on the estimated face pose. Each task performed in the app was implemented through the thread and the timer, and all tasks were executed within 75 ms. The test results showed that the time taken to register and display 120 ultrasound irradiation positions was less than 25ms, and the display accuracy was within 20mm when the face did not rotate significantly.

• Elastomers and Composites
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• v.32 no.3
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• pp.173-178
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• 1997

In this study, the ultrasonic irradiation in elevated pressure was used to alter the molecular weight and MWD of polystyrene. The high pressure reactor was filled with 0.5w/v% polystyrene solution, and then it was pressurized from 500psi to 4000psi. The ultrasound was irradiated in 10 minutes at each pressure, and the extract was collected and analyzed by GPC. Molecular weight distribution was predicted by log-normal and Schulz distribution function. The average molecular weight and polydispersity of polystyrene were decreased, as the pressure applied during the ultrasonic irradiation was increase. It was able to fractionate polymer material and control polydispersity by adjusting pressure in the ultrasonic irradiation.

• Bulletin of the Korean Chemical Society
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• v.31 no.11
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• pp.3180-3182
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• 2010

A simple facile 'one pot' synthesis of 2-amino-3-cyano-4,6-diarylpyridine derivatives via three component reaction of chalcone, malanonitrile and ammonium acetate under ultrasonic irradiation and grindstone technology. All the synthesized compounds have been characterized on the basis of their elemental analyses and spectral data (IR, $^1H$ NMR, $^{13}C$ NMR and Mass).