• Journal of Korean Society of Environmental Engineers
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• v.31 no.6
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• pp.419-427
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• 2009

To test applicability for continuous flow treatment of ultrasound technology, sonolysis of TCE aqueous solution using 584 kHz multi irradiation reactor was performed under batch and continuous flow conditions. Under batch condition (3 and 4 sides irradiation, 600 W), first order degradation rate constant of TCE was higher under 4 sides than 3 sides irradiation conditions, while the generation of $H_2O_2$ and chloride was similar under both irradiation conditions. Under continuous flow condition with 4 sides irradiation, removal efficiencies of TCE in steady-state were decreased from 83 to 48% with increasing flow rate from 67 to 300 mL/min at 600 W, and were increased from 14 to 75% with increasing acoustic power from 100 to 600 W at 100 mL/min. Removal efficiency of TCE in groundwater was decreased 10% compared to in distilled water at 100 mL/min and 600 W.

• The Journal of Korean Orthopaedic Ultrasound Society
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• v.5 no.1
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• pp.50-59
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• 2012

In the domain of orthopaedic surgery, application of regional nerve block for surgery or pain control in upper and lower extremities has been increased. By performing regional block of popliteal (sciatic), femoral, proximal saphenous nerve and ankle block under guidance of ultrasound, not only the safety, but also success rate of the procedure has increased, and amount of local anesthetics could be used less, too. Since the perineural single injection or continuous catheterization of diluted local anesthetics was performed more precisely and easily by the guidance of ultrasound, postoperative pain could be controlled without complications of PCA such as nausea, vomiting, etc. We will discuss about this ultrasound guided regional nerve block.

• Journal of the Korean Academy of Clinical Electrophysiology
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• v.4 no.1
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• pp.49-61
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• 2006

This study conducted the following experiment to examine and compare transdermal permeation effects according to parameters of ultrasound and physiochemical characteristics of meloxicam. Permeation by ultrasound among these experimental drugs was relatively higher and it was involved in COX-2 inhibition unlike other drugs. Recently use of oral agents has been rapidly increased, but it was not generalized to transdermal agent and this study selected meloxicam that transdermal permeation research using ultrasound was not performed and conducted transdermal permeation experiment with skin of hairless mouse and analyzed permeation with HPLC. It made gel first and analyzed permeation depending on frequency and intensity of ultrasound of meloxicam with the same experimental procedures as the above experiment. The results of this study can be summarized as follows. Transdermal permeation by ultrasound frequency was higher in 1.0 MHz and it was higher as intensity increased. In comparison by parameters of ultrasound, there was similar permeation in $1.0\;W/cm^2$ of continuous mode and $3.0\;W/cm^2$ of pulsed mode and it was effective to high intensity for using pulsed mode. It was found that duty cycle of ultrasound affected transdermal permeation in meloxicam gel used in this experiment and transdermal permeation was higher in used ultrasound as phonophoresis than non-ultrasound for anti-inflammatory effects.

• The Journal of Korean Physical Therapy
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• v.15 no.1
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• pp.9-25
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• 2003

The purpose of this study was to evaluate the effect of therapeutic ultrasound after muscle contusion injury by observed immunoreactivity of substance-P that plays an important role in pain transmission. Ultrasound irradiation(1MHz, 1W/$cm^{2}$ continuous mode, treatment time 5 min) was applied through water submersion technique to 1 limb daily by kept off 5cm from muscle belly of gastrocnemius. The result of this study were as follows. 1. The substance-P was expressed in lamina I and II of dorsal horn of spinal cord, also in lamina IV and around of central cannel of spinal cord. Experimental group was lower expressed than control group with the exception of 1 days. 2. The substance-P immunoreactivity was decreased for 5 days together in lumbar and sacral region of all groups, expecially experimental group was rapidly. These data suggest therapeutic ultrasound may stimulate pain relief by diminish of substance-P in dorsal horn of spinal cord.

• Membrane Journal
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• v.13 no.4
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• pp.283-290
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• 2003

To improve membrane performance, the dead-end and Cross-flow ultrafiltration with or without ultrasound irradiation onto the membrane module were carried out using a BSA protein solution. Intermittent or continuous irradiation of ultrasound effectively suppressed the formation of fouling on membrane or removed the fouling layers from membrane. Effect of ultrasound irradiation on the enhancement of ultrafiltration performance was more increased at the operating conditions which form more membrane fouling (at the operating conditions of higher feed concentration and TMP, and lower flow rate). The permeate flukes were enhanced up to 1.9 times in case of the dead-end ultrafiltration and 1.5 times in case of the cross-flow ultrafiltration by ultrasound irradiation onto the membrane module.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.20 no.8
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• pp.33-41
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• 2021

Recently, many studies have been conducted on substituting fossil fuels with bio-refineries in existing industrial systems using biomass. Among the various bio-refineries, microalgae have received wide attention because it uses inorganic compounds to produce useful substances, which are extracted by a cell disruption process. Although numerous cell disruption methods exist, cell disruption efficiency has been studied by ultrasonic treatment. Ultrasound is a high-frequency (20 kHz or higher) sound wave and causes cell disruption by cavitation when passing through a solvent. In this study, we used the microalgal species Chlorella sp., which was cultured in a plate-type photobioreactor. The experiment was conducted using a continuous low-frequency processing device. The reduction of cells with time due to cell disruption was fitted using a logistic model, and optimum conditions for highly efficient cell disruption were determined by conducting experiments under multiple conditions.

• Journal of Biomedical Engineering Research
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• v.9 no.1
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• pp.87-92
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• 1988

In this paper, a new focusing method, to be called the pipelined sampled delay focusing (PSDF), is implemented. This method improves the lateral resolution in ultrasound imaging system. In PSDF, the analog belay lines are no longer necessary because sampling sum process can replace the conventional delay sum process. Also, the method offers continuous dynamic focusing on the resolution pixel basis, and eliminates the constraint that the maximum delay time is less than the sampling interval. Second order sampling is adopted in order to extend the sampling interval.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.7
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• pp.706-713
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• 2010

The research seeks to find the optimal conditions for sonodegradation of naphthalene and phenol as exemplary organic pollutants to be subjected to ultrasound in varying frequencies (28 kHz, 580 kHz, and 1,000 kHz) and in the presence of different kinds of additive (T$TiO_2$, $H_2O_2$, $FeSO_4$, Zeolite, and Cu). In cases of both naphthalene and phenol, 580 kHz of ultrasound has proven to be the most effective among others at sonodegradation. Based on the observation that OH radicals are also produced in maximum under exposure of 580 kHz of ultrasound, we concluded that this frequency of ultrasound creates hospitable condition for the combined process of degradation by pyrolysis and oxidization. $FeSO_4's$ degradation rate and k1 value have increased by approximately 1.8 times compared with the results of the solutions without any additives. This seems to be the result of ultrasound reaction which, accompanied by Fenton's reaction, increased the oxidative degradation and the production of OH radicals. However, application of ultrasound and Fenton's reaction is limited to the batch type conditions, as its use in continuous system can cause loss of iron or decay of the cistern, thereby creating additional pollutants. When the additive is replaced with $TiO_2$, on the contrary, the rate of sonodegradation has increased up to 20% compared to when there was no additive. We therefore conclude that $TiO_2$ could prove to be an effective additive for ultrasound degradation in continuous treatment system.

• The Journal of Korean Physical Therapy
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• v.13 no.3
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• pp.719-726
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• 2001

Transdermal drug delivery offers various advantages over conventional drug delivery systems, such as avoidance gastrointestinal degradation and hepatic first-pass effect. encourages patient compliance. and possible sustained release of drugs. However, transdermal transport of drugs is low permeability of the stratum corneum, the superficial layer of the skin. Many physicochemical and biological factors influencing transdermal transport is described together with the corresponding experimental and clinical results. Phonophoresis is medical treatment with drugs introduced into the skin by ultrasound energy. Enhanced drug penetration is through to result from the biophysical alterations of skin structure by ultrasound waves. The frequency used for phonophoresis is usually from 20 kHz to 15MHz. Phonophoresis can be categorized in to three ranges: low-frequency range(below 1 MHz). therapeutic frequency range(1 to 3MHz), and high-frequency range(above 3 MHz). The depth of penetration of ultrasound into skin is inversely proportional to the frequency. Cavitation may cause mechanical stress. temperature elevation, or enhanced chemical reactivity causing drug transport. One theory is that ultrasound affects the permeation of the stratum corneum lipid structure as the limiting step in permeating through the skin. The range of indications for phonophoresis is wide. Aspecific classification of the range of indications is obtained by classification of pathological conditions. The continuous research is needed for many interesting issucs of phonophoretic transdermal delivory in new future.

• Applied Chemistry for Engineering
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• v.20 no.5
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• pp.532-535
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• 2009

In this study, the fatty acid methyl ester was prepared from the vegetable oil by inducing ultrasound energy. The ultrasound energy was applied to the esterification reaction for heating and stirring effects. Ultrasonic induction results in the shortened reaction time and brings the increase of the methyl ester yield. However, the continuous introduction of ultrasound during the esterification reaction results in temperature increase, then the over-heating of reaction temperature was ineffective. Therefore, the system temperature was controlled at constant temperature state with the cooling circulation. The ultrasound induction reaction had the fatty acid methyl ester yield of 93% at the reaction time was 30 minutes, faster than the traditional esterification process.