• Journal of the Korean institute of surface engineering
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• v.47 no.6
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• pp.275-281
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• 2014

An ultrasound-assisted Sn-Ag-Pd activation method for electroless copper plating was presented in this study. With this activation process, it was shown that the fine catalyst particles were homogeneously distributed with high density on the entire specimen. In addition, it was observed that incubation period occurred during the electroless plating step was decreased owing to the absorption of Ag which holds high catalytic activity. Resulting from the refinement and high densification of catalyst, the defect-free gap-fill was achieved within the 20x nm trench.

• Advances in nano research
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• v.2 no.2
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• pp.121-133
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• 2014

Polymer nanocomposites are advanced nanomaterials which exhibit dramatic improvements in various mechanical, thermal and barrier properties as compared with the neat polymer. Polystyrene/ alumina nanocomposites were prepared by an ultrasound-assisted solution casting method at filler loadings ranging from 0.2 to 2% and also at different ultrasonic frequencies, viz. 58 kHz, 192/58 kHz, 430 kHz, 470 kHz and 1 MHz. The composites were subjected to mechanical property tests (tensile and impact tests) and cavitation erosion tests to study the enhancement in functional properties. Filler dispersion in the polymer matrix was observed by SEM analysis. The effect of frequency on filler dispersion in the matrix was studied by SEM analysis and functional property enhancement of the composite material. The composites prepared at dual (high/ low) frequency (192/58 kHz) were found to show better property enhancement at low filler loadings as compared with neat polymer and also with composites prepared without ultrasound, thus reinforcing the finding that ultrasound-assisted synthesis is a promising method for the synthesis of nanocomposites.

• Korea-Australia Rheology Journal
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• v.17 no.4
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• pp.165-170
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• 2005

In this study, high intensity ultrasound was employed to induce mechano-chemical degradation during melt mixing of polycarbonate (PC) and a series of styrene-acrylonitrile (SAN) copolymers. It was confirmed that generation of macroradicals of constituent polymers can lead to in-situ copolymer formation by their mutual combination, which should be an efficient path to compatibilize immiscible polymer blends and stabilize their phase morphology in the absence of other chemical agents. Based on the effectiveness of the compatibilization by ultrasound assisted mixing process, we investigated the effects of viscosity ratio of PC and SAN and AN content in SAN on the compatibilization of PC/SAN blends. It was found that effectiveness of compatibilization is optimal when the AN content is in the range of favorable interaction with PC and the viscosity of the matrix is higher than that of the dispersed phase. In addition, changes in the interfacial tension between PC and SAN were assessed by examining relaxation spectra which were obtained from measuring rheological properties of ultrasonically treated blends.

• CELLMED
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• v.5 no.3
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• pp.19.1-19.2
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• 2015

This is a case report involving a novel setting of sonographic scan for thickness of superficial abdominal fat and a non-invasive approach for reduction of the fat thickness. A 38-year-old woman complained of her abdominal contour asymmetry after the laser-assisted liposuction performed two years ago. Compression-free sonographic scanning confirmed that her superficial abdominal fat was thicker in left side than that of right side. After 9 sessions of 40KHz therapeutic ultrasound, the contour asymmetry was reduced.

• Bulletin of Food Technology
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• v.24 no.4
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• pp.605-612
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• 2011

• Korean Journal of Fisheries and Aquatic Sciences
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• v.56 no.1
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• pp.28-32
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• 2023

We optimized ultrasound-assisted extraction to improve the extraction efficiency of bioactive compounds from the microalgae Acutodesmus reginae. To optimize this extraction process, we investigated the effects of solvent type, solvent concentration, extraction time, extraction number, and extraction power on the production of lutein, α-carotene, β-carotene, and chlorophylls a, and b. After sequential optimization of these main variables, the maximum amount of each compound was extracted at 30℃ with an ultrasound power of 80 W and using 99.5% methanol. Under these optimum conditions, the amount of lutein, α-carotene, β-carotene, and chlorophylls a, and b, were measured as 10.43, 8.66, 3.76, 15.43, and 6.39 mg/g dry matter respectively.

• Journal of Chest Surgery
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• v.53 no.5
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• pp.313-316
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• 2020

Esophageal perforation after endoscopic ultrasound-guided fine-needle aspiration for mediastinal staging is a rare but severe complication. We report 2 cases of patients with esophageal perforation who were treated using video-assisted thoracoscopic surgery in combination with esophageal stenting. Through these cases, the feasibility of minimally invasive thoracic surgery was evaluated.

• The Korean Journal of Pain
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• v.27 no.1
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• pp.81-85
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• 2014

Postherpetic neuralgia (PHN) is one of the most difficult pain syndromes to treat. Invasive treatments may be considered when patients fail to obtain adequate pain relief from noninvasive treatment approaches. Here, we present three cases of PHN in the mandibular branch treated with ultrasound-assisted mental nerve block and pulsed radiofrequency treatment. None of the patients had adequate pain relief from the medical therapy, so we performed the mental nerve block on the affected side under ultrasound assistance. Two patients showed satisfactory pain relief continuously over 12 months without any further interventions, whereas one patient only had short-term pain relief. For the patient had short-term pain relief we performed pulsed radiofrequency treatment (PRFT) on the left mental nerve under ultrasound assistance. After PRFT, the patient had adequate pain relief for 6 months and there was no need for further management.

• KSBB Journal
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• v.25 no.5
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• pp.437-442
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• 2010

The objective of this study was to investigate the effect of ultrasound on the extraction of oil from canola seeds when supercritical carbon dioxide ($SCCO_2$) was used as an extraction solvent. The ultrasound-assisted $SCCO_2$ extraction were carried out while varying such operating parameters as particle size of crushed canola seed, flow rate of $SCCO_2$, aspect ratio of the extraction vessel, and ultrasound power. The extraction rate decreased with increasing particle size of samples, showing a maximun at a $CO_2$ flow rate of 6.2 L/min. Both the extraction rate and extraction yield increased with a decrease in the aspect ratio of the extraction vessel. For the ultrasoundassisted $SCCO_2$ extraction, the extraction yield was slightly increased when the $CO_2$ flow rate was below 6 mL/min with sample A and B.

• Fisheries and Aquatic Sciences
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• v.26 no.9
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• pp.535-547
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• 2023

Sea cucumbers (Holothuria scabra), also known as beche-de-mer, are highly valued as a luxurious food item and have been utilized as a traditional tonic food in various Asian countries for centuries. The body walls of sea cucumbers are the main edible part, which are primarily composed of glycosaminoglycan (GAG). The rehydration of dried sea cucumber is a crucial step prior to further processing. The aim of this study was to assess the impact of ultrasound-assisted rehydration (UAR) on the quality of dried sea cucumbers. The experiment used four different rehydration methods, including conventional methods at 27℃ (KV27℃) and 15℃ (KV15℃), as well as a combination of ultrasound at 27℃ with conventional at 15℃ (UAR27 + KV15℃) and ultrasound at 15℃ with conventional at 15℃ (UAR15 + KV15℃). Results indicated that the rehydration rate (RR) was significantly affected by both the rehydration method and the temperature used (p < 0.05). UAR27 + KV15℃ was identified as the most effective method in terms of rehydration behavior and quality characteristics of dried sea cucumber, with a RR of 0.58 ± 0.53 gH₂O/hour and reduced rehydration time of up to 28 hours. Moreover, the UAR27 + KV15℃ method demonstrated superior rehydration potential, nutritional value (proximate composition and sulfate content), color, lower energy, and microstructure properties compared to the other methods. The sulfate content and yield of sulfated GAGs were determined to be 89.4 mg/g and 52.8 ㎍/g, respectively. Confirmation of the absorption band of the sulfate group showed the presence of 3-N-acetyl galactosamine at a wavelength of 1,269 cm^-1 and C-O-S at 860 cm^-1. The sea cucumbers treated with UAR exhibited a GAG content approximately 2.9 times higher than those rehydrated with the conventional method. Eventually, the combination of UAR at 27℃ with conventional at 15℃ methods can significantly accelerate the rehydration of sea cucumber without negatively affecting its physical quality properties.