• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.11a
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• pp.287-288
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• 2008

에폭시-층상실리케이트 나노콤포지트의 균질분산과 층상실리케이트내로 침투되는 박리정도를 향상시키기 위해 친환경적 분산기법인 물리적방법으로 Homogenizer와 Power Ultrasonic를 적용한 기법을 실시하였다. Homogenizer의 최적속도를 얻기 위해 분산시킨 나노콤포지트의 박리정도, 유리천이온도를 구할 수 있었고, Homogenizer와 Ultrasonic을 동시에 적용하여 최적시간을 구하기 위해 적용된 나노콤포지트를 절연파괴 강도의 Weibull Plots을 통하여 판단할 수 있는 좋은 결과를 얻을 수 있었다.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.5
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• pp.700-706
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• 2005

The objectives of this research were to analyze physicochemical properties of physically modified rice starch which was prepared by hydro-shear homogenizer and ultrasonic homogenizer. The 5:1 of water to starch ratio, 20,500 rpm of hydro-shear homogenizer, and 5 sec of pulse and 40 kHz of frequency of ultrasonic homogenizer, which were operated for 10 min. The 1/3 of size reduction of raw rice starch and gelatinized rice starch, and reduced of particle size were achieved by above processing conditions. The homogenization of raw rice starch and gelatinized rice starch were higher values of specific area, transmittance, solubility and swelling power than control. While, these had lower value of apparent viscosity than control. In raw rice starch, the gelatinization characteristics of ultrasonic homogenizer treated rice starch had some higher values of gelatinization temperature, peak temperature and enthalpy than those of control. While, those of hydro-shear homogenizer treated rice starch had similar values to those of control.

• Journal of Environmental Science International
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• v.24 no.9
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• pp.1181-1188
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• 2015

In this study, we discussed about the application of the single physical and chemical treatment processes and the physical-chemical complex treatment processes on the inactivation of Artemia sp. in order to satisfy the USCG Phase II (United States Coast Guard). The results showed that initial disinfection rate of ultrasonic process in single batch process is higher than that of electrolysis. However, the inactivation rate showed slower than electrolysis. The inactivation rate of Artemia sp. on the single continuous treatment process ranked in the following order: homogenizer > electrolysis > ultrasonic process. Inactivation rate of Artemia sp. in continuous homogenizer-electrolysis complex process was reached at 100% immediately. A synergistic effect of ultrasonic-electrolytic complex process was found to be a small. The order of processes in a complex process did not affect the disinfection performance.

• Journal of the Korean Applied Science and Technology
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• v.24 no.3
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• pp.264-271
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• 2007

Effect of dispersion methods for Vapor Grown Carbon Fibers (VGCF) in epoxy caused the change in mechanical properties of VGCF/epoxy nanocomposites, such as tensile modulus and tensile strength. The influence of VGCF types - atmospheric plasma treated (APT) VGCF and raw VGCF - and their contents was discussed in detail. Treating VGCF with atmospheric plasma enhanced the surface energy, therefore improved the bonding strength with epoxy matrix. Two different methods used to disperse VGCF were ultrasonic and mechanical homogenizer methods. When using dispersion solutions, the VGCF demonstrated good dispersion in ethanol in both homogenizer and ultrasonic method. The uniform dispersion of VGCF was investigated by scanning electron microscopy (SEM) which showed well-dispersion of VGCF in epoxy matrix. The tensile modulus of raw VGCF/epoxy nanocomposites obtained by ultrasonic method was higher than that of one obtained by homogenizer method. APT VGCF/epoxy nanocomposites showed higher tensile strength than that of raw VGCF/epoxy nanocomposites.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2003.10a
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• pp.29-32
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• 2003

Multi -walled carbon nanotube(MWNT)/poly(methyl methacrylate) composites were fabricate d through film casting. Manufacturing process was established using a ultrasonic cleaner and a homogenizer. Acetone was used as a solvent to melt PMMA and mix with MWNT. The ultrasonic cleaner performed an important role in producing MWNT/MMA nanocomposites. Ultrasonic energy was utilized to disperse MWNT in acetone. Also, melting PMMA in acetone and mixing MWNT and PMMA were achieved using the homogenizer. It was confirmed that the nanohlbes were well dispersed in PMMA according to SEM images.

• The Journal of the Acoustical Society of Korea
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• v.41 no.1
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• pp.9-15
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• 2022

In order to overcome the limitation of conventional nanoparticle dispersion methods such as sonicator or homogenizer, a filtration method using an ultrasonic atomization effect and cyclones was proposed in this study. A 0.5 wt% suspension was made with Al₂O₃ powder with an average diameter of 250 nm. The suspension was filtered by the proposed method after pre-dispersing using a sonicator and a homogenizer, respectively. As the result, in the case of the suspension after pre-dispersing with a sonicator, the particle size distribution of the filtered suspension started showing up a single normal distribution indicating the mode of the average diameter only after the 3rd cyclone process. On the other hand, in the case of the suspension with the homogenizer pre-dispersion, similar results appeared from the 2nd cyclone process. Filtration of various types of nanoparticles is expected to be possible by adjusting ultrasonic atomization frequency and manipulating the design of the cyclone.

• Journal of the Korean Applied Science and Technology
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• v.25 no.3
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• pp.395-403
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• 2008

In this study, the characteristics of emulsified fuel were studied. The emulsified fuel which was composed of water and diesel was manufactured by using homogenizer and ultrasonic generator. The more the percentage of water contents increases, the more the density increases to the emulsified fuel. However, the viscosity increased in the 60% of water contents and decreased in the 70% of water contents because the O/W type was formed. The 3 minutes's ultrasonic waves during the irradiation time was appropriate of 16,000 rpm. And the energy density of ultrasonic waves was 87.5J/g. The emulsion stability has improved in the lower temperature, the lower percentage of water contents, and the most stable emulsion state was obtained from 20%(w/w) of water contents. Also, the emulsion stability was related to the HLB values of emulsifiers. Especially, the HLB values of emulsifier were appropriate from 4 to 7 values.

• Applied Chemistry for Engineering
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• v.1 no.2
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• pp.224-231
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• 1990

To improve the dispersion of platinum catalyst, the effects of carbon black surface treatment, solvents, surfactants, and ultrasonic homogenizing were examined. Upon introducing the hydrophilic groups acting as an anchorage center of the catalyst on the surface of carbon black by oxidation, the migrating and growing of platinum particles(or ions) during reduction could be restricted. When mixed solvents, surfactants, or ultrasonic homogenizer were used to disperse catalysts on the carbon black, the dispersion of catalyst could be improved, due to the good permeation of chloroplatinic acid through the pore of carbon black. Among the impregnation methods, the method using ultrasonic homogenizer with mixed solvent was the most excellent. Using this method the particle sized could be minimized in less than $30A^{\circ}$ and distributed homogeneously.

• Journal of the Korean Society of Marine Environment & Safety
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• v.5 no.2
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• pp.67-78
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• 1999

Recently, a greater part of all ship use a coarse heavy fuel oil(HFO) over specific gravity(S.G) 1.00/15$^{\circ}C$ and viscosity 3,500 cSt/4$0^{\circ}C$ as the fuel oil of marine boiler or internal combustion engine from the viewpoint of economical ship' operation. The greater plan to improve a combustion methods of heavy fuel oil, such as atomization, homogeneity and emulsification, were contrived and carried out newly, and then applied 20kHz ultrasonic homogenizer to one of test methods. Also, adopted the marine oils(fuel oil and lubricating oil etc.) and sludge oil as test solutions, and its matrix structures were examined with photographs, Especially, it is important at control system of oil pollution, for the sludge oil emulsified, to be recycled as fuel oil of boiler according to 20kHz Ultrasonic homozenizer, and then fuel saving is attained effectively by making sludge oil to be burnt.

• Proceedings of the Membrane Society of Korea Conference
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• 1996.04a
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• pp.1-4
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• 1996

유화제의 물리화학적인 성질을 이용하여 O/W와 W/O에멀젼을 제조하는 방법(예:PIT method, D-phase method)은 이제까지 많은 연구가 진행되어 왔으며, colloid mill, homogenizer, ultrasonic emulsifier와 같은 유화장치도 지속적으로 개발 및 개선되고 있다. 하지만 이들 방법은 공정의 정확한 조절이 어려우며, 제조된 에멀젼의 입자크기 분포가 다분산적(polydispersed)이라는 단점을 가지고 있다. 이를 극복하기 위한 방법으로 1980년대 중반에 일본에서 처음으로 개발된 막유화법이 있다. 이 기술은 pouous glass membrane 가운데 기공크기(pore size)가 균일한 SPG(Shirasu Porous Glass)막을 사용하여 균일한 입자분포를 가지는 에멀젼을 제조하는 것이다. 한편 막유화에 사용되는 막이 갖추어야 할 조건은 다음과 같다.