• 한국식품과학회지
• /
• 제51권2호
• /
• pp.103-108
• /
• 2019

본 연구는 더덕 사포닌의 최적 추출 방법을 구명하기 위해 수행되었다. 추출 방법에 따른 lancemasides 함량을 조사하기 위해 환류 추출(MeOH, BuOH), 열수 추출(Hot water), 초음파 추출(ultrasonic bath (40 kHz; continuous irradiation, interval irradiation), ultrasonicator (20 kHz))을 실시하였다. 그 결과, 총 lancemasides함량은 ultrasonic bath (MeOH; continuous irradiation) 추출에서 가장 높았고, ultrasonic bath (water; continuous irradiation) 추출>ultrasonic bath (MeOH; interval irradiation) 추출>ultrasonicator 추출>열수 추출>메탄올 환류 추출>부탄올 환류 추출 순으로 높았다. 따라서 더덕 사포닌의 최적 추출 방법은 MeOH을 이용한 초음파(ultrasonic bath, 40 kHz) 추출이었고, 추출 전 시료 건조 방법은 동결건조보다 음건으로 건조하는 것이 lancemasides 추출에 더 효과적이었다. 또한 초음파 추출 시 추출 시간은 2시간, 추출 온도는 $64^{\circ}C$에서 추출 하는 것이 효과적임을 확인할 수 있었다. 따라서 초음파(ultrasonic bath)추출은 기존에 주로 이용하던 환류 추출 및 분획을 실시했을 때 보다 많은 양의 사포닌(lancemasides)을 추출할 수 있었다. 그리고 추출 시간과 온도와 같은 추출 조건에 따라 aster saponin Hb가 lancemaside류로 성분 변화가 일어나는 것을 확인하였다. 특히 추출 온도가 증가함에 따라 aster saponin의 함량이 줄어들고, lancemaside A의 함량이 증가하는 것으로 보아 추출 온도가 사포닌 성분 변화에 영향을 주는 것으로 사료된다.

• Applied Microscopy
• /
• 제28권3호
• /
• pp.315-328
• /
• 1998

The present study was carried out to investigate the effect of ultrasonic bath in tissue preparation for transmission electron microscopy. The method used standard reagents and media, and employed ultrasonic bath agitation to accelerate fluid exchange. The liver kidney, stomach and cardiac muscle tissues of male Sprague-Dawley rats were used for the experiment, and the experimental design was divided into 4 groups; The control group using rotators (Traditional method, 1,625 mins) and the three experimental groups using ultrasonic bath (UB) in the primary fixation through the infiltration processes (UB I; 62.5 mins, UB II; 125 mins, UB III; 250 mins). The results were as follows; 1. In the control group, tissues were easily sectioned, and showed well preserved intact membranes, and cell organelles such as mitochondria, lysosome, peroxisome, rough endoplasmic reticulum and smooth endoplasmic reticulum. 2. In the UB treated group I, tissues showed holes due to the inadequate removal of both water and fluids used in the dehydration process. Also the mitochondria of cell organelles, especially, showed swollen intracristal spaces and dense matrices due to poor fixation. 3. In the UB treated group II, tissues showed good preservation of cell organelles and specimen slice sections. Also, no holes were observed. 4. In the UB treated group III, tissues showed leaching of structural components in the cytoplasm, but no holes were observed. In conclusion, the ultrasonic bath procedure takes approximately 120 minutes from specimen fixation to resin infiltration and gives excellent results.

• 한국염색가공학회지
• /
• 제11권5호
• /
• pp.1-6
• /
• 1999

This study was carried out to investigate the effect of a scouring machine including an ultrasonic system on desizing and scouring polyester fabrics. The ultrasonic frequency of the improved machine showed up at 28.882 kHz. Frequency amplitude increased with the current and the bath temperature, and then showed a constant level. Scouring effect of the ultrasonic machine was better than that of the conventional scouring machine using the mechanical stirring. The ultrasonic machine showed the optimum scouring effect at $50^\circ{C}$ of bath temperature and 10 min. of operation time, as compared to the conventional machine that required operating conditions of high temperature at $90^\circ{C}$, stirring speed at 40 rpm, and stirring time for 15 min..

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2003년도 추계학술대회
• /
• pp.905-909
• /
• 2003

This paper describes a shower type ultrasonic cleaning system using particle acceleration, developed for better effectiveness in washing out agricultural chemicals from fruits or vegetables, compared to the existing bath type ultrasonic cleaning system. The shower type system consists of a signal generator, a transducer, and a spouting nozzle, mainly. The system has been tested based on the method recommended by Korea Food and Drug Administration. It is found that shower type system shows better performance and cost-effectiveness than the bath type system that is commercially available .

• 한국염색가공학회지
• /
• 제12권3호
• /
• pp.207-217
• /
• 2000

A new, high-efficiency ultrasonic fabric washing machine was developed to be an energy-efficient washing machine and to enhance fabric washing quality in washing processes of the dyeing and finishing process in the textile industry. This system is composed of ultrasonic wave generator, air blowing nozzle, torque motor for fabric tension control, and enclosed washing bath, multi-tube type exchanger, noiseless heater, air cylinder, expander roller, mangle upper and lower rollers, bend bar, dancer, shower spray nozzle, and solenoid valve, and so on. These elements are synergised for fabric washing. One of the very important principles is the low tension fabric running system. For an efficient washing effect, a counter flow system is also adopted. The new system also adopts the dancer and torque motor to control fabric tension and prevent fabric creasing. Shower spray nozzle, counter flow and overflow apparatus, and air-blowing apparatus are adopted to enhance the fabric washing effect. In this study, peach yoryu, exter, and moss crepe fabrics were washed by the general and ultrasonic washing systems under different conditions respectively. The washing efficiency was affected by the fabric running speed and characteristics of fabrics. Size content after washing increased with increasing the fabric running speed. The values in the general washing system were higher than those of the ultrasonic washing system. The changes of conductivity in the ultrasonic and the cooling bath were affected by the running time under the ultrasonic generating. The values of conductivity decreased as the experimental time passed.

• 한국표면공학회지
• /
• 제21권4호
• /
• pp.168-175
• /
• 1988

The nickel0zinc allot depositions have been studjen in ammonium chloridw added chloride baths to fine out the effects of ultrasonic irradiation for the electrodeposition processes. The compositions of deposited alloys, the current efficiencies, corrosion resistance and brightness in various conditions of electrodeposition were investigated, in the range of ultrasonic irradiation of 50,500 and 1,000kc/s respectively. The results obtained are as follows; 1. the ratio of nikel to zinc in the deposit increased according 시 the ammonium chloride concentration in irradiated baths. 2. The current efficiencies became also higer in the irradiated bath. 3. Ammonium ions in solution seem to retard formation of zinc hydroxide. 4. The corrsion resistance and brightness of the deposits are dependent upon nickel content of deposits which ranges 10-18%(wt)nickel in the irradiated baths and 11-15%(wt)in ninirradisted baths. 5. The corrosion resistance and brightnes of the deposited are appreciably better in the irradiated baths than in non-irradiated bath with the mole ratio of 3.4(NH+4/Ni+++Zn++).

• 한국표면공학회지
• /
• 제43권5호
• /
• pp.243-247
• /
• 2010

The micro Vickers hardness and internal stress of Ni-Fe metal thin film synthesized by electrodeposition method at $25^{\circ}C$ were studied as a function of bath composition, and surface microstructure and atomic compositions of thin films were investigated by SEM and EDS. And the shape change of $200\;{\AA}$ Ni-Fe nanowires made using anodic aluminum oxide(AAO) templates by electrodeposition method were observed by SEM as a function of ultrasonic treatment time and bath composition. The Fe deposition contents on the substrate non-linearly increased with Fe ion concentration over total metal ion concentration. In case of low Fe contents film, the grain size is smaller and denser than high Fe contents deposited films, and the micro Vickers hardness increased with Fe contents of electrodeposited films. These results affected the shape change of nanowire after ultrasonic treatments.

• 한국지하수토양환경학회지:지하수토양환경
• /
• 제22권5호
• /
• pp.40-47
• /
• 2017

The effects of ultrasound in heterogeneous system were investigated in three kinds of ultrasonic systems including a bath-type system (System #1), a double-bath-type system (System #2), and a double-bath-type system partly filled with glass beads (System #3). The ultrasound energy and its attenuation were quantified using calorimetry and the sound pressure measurement method. The sonochemical effects mainly involved in radical oxidation reactions were quantified using KI dosimetry. It was found that ultrasound energy was significantly attenuated in System #2 and #3 due to the presence of solid materials such as a submerged stainless steel reactor and glass beads. However, in spite of low ultrasound energy status, sonochemical oxidation reactions occurred more violently due to the presence of glass beads in System #3. In addition, calorimetry was more adequate to estimate the total energy status of ultrasound in sonoreactors compared to the sound pressure measurement method.

• 자원리싸이클링
• /
• 제20권6호
• /
• pp.50-55
• /
• 2011

태양전지(Photovoltaic, PV) 모듈의 층간 접착제로 사용된 EVA(Ethylene Vinyl Acetate)를 초음파 조사(irradiation)를 이용하여, 선택적으로 분해함으로써 모듈 내 실리콘웨이퍼(Si-wafer)로 제조된 셀(cell)을 분리, 회수하는 연구를 진행하였다. 본 실험에 사용한 초음파 발생장치는 bath-type의 초음파 세척기 (Output: 130 W, Frequency: 40 kHz)로, PV모듈과의 거리는 2 cm로 고정하고 유기용매 종류, 농도, 온도를 조절하면서 EVA 분해 및 셀의 분리 최적 조건을 도출하였다. $55^{\circ}C$, 5M인 조건에서는 용매 종류에 상관없이 160 min 이내에 EVA층의 완전 분해는 가능하였으나, 분해과정 중 발현되는 팽창현상(swelling)에 의해 셀의 일부분이 파손된 상태로 회수되었다. 반면에 $65^{\circ}C$, 5M조건에서는 셀의 파손이 억제된 상태로 회수 가능하였으며, 이는 온도 상승에 의해 EVA 성분의 분해속도가 상승되고, 이로 인해 EVA층의 팽창현상이 발현되기 전에 분해가 일어난 결과라고 판단된다.

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2002년도 학술대회지
• /
• pp.655-658
• /
• 2002

The present paper investigated the effect of ultrasonic vibrations on the melting process of a phase-change material (PCM). Furthermore, the present study considered constant heat-flux boundary conditions unlike many of the previous researches, which had adopted constant wall-temperature conditions. Therefore in the study, modified dimensionless numbers such as Stefan and Rayleigh were adopted to represent heat transfer results. The experimental results revealed that ultrasonic vibrations accompanied the effects like agitation, acoustic streaming, cavitation, and oscillating fluid motion, accelerating the melting process as much as 2.5 times, compared with the result of natural melting (i. e., the case without ultrasonic vibration). Such effects are believed to be a prime mechanism in the overall melting process when ultrasonic vibrations were applied. Subsequently, energy could be saved by applying the ultrasonic vibrations to the natural melting In addition, various time-wise dimensionless numbers provided a conclusive evidence of the important role of the ultrasonic vibrations on the melting phenomena of the PCM.