• Journal of Pharmaceutical Investigation
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• v.17 no.1
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• pp.38-40
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• 1987

To optimize the preparation condition of oil in water microemulsion rheological method was used. The viscosity-temperature curve of refined soybean oil was recorded and from this result microemulsion was prepared at various temperatures and evaluated by Coulter counter during 3 weeks. The difference in rheograms of crude emulsion and the microemulsion varying the number of passes in the homogenizer was also examined. From above experiments following conclusions were obtained. 1) Through all the process, temperature was an important factor and the optimum was $60-80^{\circ}C$. 2) By first pass in the homogenizer, most oil droplets were finely dispersed. 3) In the homogenizing step the higher pressure results in the finer dispersion but as the pressure goes up, the differential efficiency of dispersion was decreased.

• Journal of the Korean Society of Industry Convergence
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• v.19 no.2
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• pp.50-61
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• 2016

This study proposes a new approach to control the nozzle pressure of homogenizer in refrigerator foam system in the 900L class. Generally, dynamic characteristics of the hydraulic nozzle system is highly nonlinear due to uncertain parameters, and it is very difficult to control of hydraulic dynamics. Firstly, it has been performed to derive a real-time control algorithm based on the mathematical model of hydraulic cylinder, and to estimate the values of the unknown parameter in the hydraulic system. Secondly, the feedback controller was designed to implement the optimal pressure control of the hydraulic nozzle system. Finally the control performance was illustrated by simulation.

• Membrane Journal
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• v.6 no.3
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• pp.166-172
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• 1996

For the preparation of polybutadiene latexes with suitable particle size, membrane e$$\mu$sification, which is capable of easy and uniform control of particle size, was used in this study. The parameters were the type and amount of surfactants, amount of additive and pressure. Particle size and distribution of prepared latexes were measured and compared with those of e$$\mu$sion prepared by homogenizer. To investigate the membrane e$$\mu$sification mechanism, theoretical drop size was calculated by Harkins-Brown equation. When the amount of surfactant with more than 0.2 wt%(based on DDI water) was added in the continuous phase, the stable e$$\mu$sion was prepared. Other parameters showed little relationship with particle size and distribution. In this membrane e$$\mu$sification, the essential factor for determining the particle size was the pore size of the membrane.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.39-40
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• 2008

유기용매를 사용한 나노분산체의 경우, 유기용매를 완전하게 제거 것은 극히 어렵다. 이는 유기용매와 유기고분자와의 일부 반응되는 경우가 발생되어 전기적 물성에 영향을 줄 수 있다. 본 연구는 친환경적인 분산기법으로 물리적 분산기법을 제안하는 바이다. 양호한 분산체를 얻기위해 균질한 상태인 마이크로적 분산기법과 층상실리케이트인 층간사이에 고분자인 에폭시분자가 삽입되어 박리가 양호하게 일어나게 하는 나노적인 분산기법을 통시에 적용하여 분산이 훌륭하게 일어나는 경우를 개발하였다. 마이크로적인 분산을 위해 사용된 Homogenizer의 적용속도와 적용시간에서 원형인 Organoclay_10A Powder의 d-spacing이 262%, 263%로 증가되는 결과를 얻었다. 또한 DSC의 유리천이온도 분석에서도 적용시간의 증가에 따라 유리천이온도가 되어 원형에폭시수지에 비하여 $9^{\circ}C$상승된 결과를 얻을 수 있었다.

• Journal of Pharmaceutical Investigation
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• v.16 no.2
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• pp.68-71
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• 1986

Oil in water microemulsion which has many pharmaceutical applications was prepared and evaluated. As oil sources and emulsifier, two grades of oil and egg phosphatide were used, respectively. Vacuum high shear mixing and high pressure homogenizing were performed and in the homogenizing step, effect of the number of passes in the homogenizer on the stability of microemulsion was studied, using Coulter counter, photographic microscope and pH-meter. From above results, it was concluded that the stability of microemulsion made of refined soy-bean oil was better than that of food grade soybean oil and by five passes in the homogenizer at 6,000 psi, we could make stable microemulsion with average particle diameter below $1\;{\mu}m$, with no particle above $5\;{\mu}m$ and no significant change during 6 weeks stored.

• Transactions on Electrical and Electronic Materials
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• v.9 no.5
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• pp.209-212
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• 2008

We developed a simple and effective purification method to obtain high-purity single-walled carbon nanotubes (SWCNTs) with low surface damage. The purification process consists of oxidization at $430^{\circ}C$ for 1 h in a furnace system of air atmosphere and homogenization in dilute hydrochloric acid solution for extremely short time. The role of homogenizer was examined during purification process in terms of purity and quality of purified SWCNTs. High-purity and low surface damage of SWCNT products was obtained using homogenizer which was operated at 8500 rpm for 10 min in the environment of 7 % HCI solution. From XRD spectra, we observed that metal catalysts were thoroughly removed. Raman spectra showed that the intensity values of crystallization ($I_{G}/I_{D}$) of purified SWCNTs were very similar with that of pristine SWCNTs. Moreover, the structure damage of purified SWCNTs was hard to find from electron microscopy. Consequently, homogenizing, which is a quick and simple manner, can be promising method for obtaining final SWCNTs with clearly high purity and crystallinity.

• Journal of Dairy Science and Biotechnology
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• v.41 no.1
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• pp.1-8
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• 2023

Response surface methodology (RSM) is a statistical approach widely used in food processing to optimize the formulation, processing conditions, and quality of food products. The homogenization process is achieved by subjecting milk to high pressure, which breaks down fat globules and disperses fat more evenly throughout milk. This study focuses on an application of RSM including the logit transformation to predict the efficiency of milk homogenization, which can be maximized by minimizing the relative difference in fat percentage between the top part and the remainder of milk. To avoid a negative predicted value of the minimum of this proportion, the logit transformation is used to turn the proportion into the logit, whose possible values are real numbers. Then, the logit values are modeled and optimized. Subsequently, the logistic transformation is used to turn the predicted logit into the predicted proportion. From our model, the optimum condition for the maximized efficiency of milk homogenization was predicted as the combination of a homogenizer pressure of 30 MPa, a storage temperature of 10℃, and a storage period of 10 days. Additionally, with a combination of a homogenizer pressure of 30 MPa, a storage temperature of 10℃, and a storage period of 50 days, the level of milk homogenization was predicted to be acceptable, even with the problem of extrapolation taken into account.

• Korean Chemical Engineering Research
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• v.58 no.4
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• pp.530-535
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• 2020

A ceramide-containing nanoemulsion was synthesized by using a High-Pressure Homogenizer (HPH) to observe its changes in properties and long-term stability. The droplet size, droplet distribution and zeta potential of nanoemulsion were examined by varying the pressure and the number of passes of the HPH. The increase in HPH pressure and number of passes decreased the average droplet size and made the nanoemulsion more uniform. However, beyond certain operating condition, the recombination between the droplets was confirmed due to droplet surface energy and emulsifier. This study also shows that the decrease in droplet size increased the nanoemulsion viscosity although only minimal changes occurred in the zeta potential. The formed nanoemulsion was then tested for its stability by storing it at 25 and 45 ℃ for 28 days. During the first week, the average droplet size increased due to recombination and then subsequently remained constant. We confirmed that ceramide nanoemulsion for industrial application could be synthesized by using HPH.

• Journal of the Korean Wood Science and Technology
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• v.39 no.3
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• pp.197-205
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• 2011

Cellulose nanofibrils (CNF) with 50~100 nm diameter were manufactured from micro-size cellulose by an application of a high-pressure homogenizer at 1,400 bar. High strength nanopapers were prepared over a filter paper by a vacuum filtration from CNF suspension. After reinforcing and dispersing CNF suspension, hydroxypropyl cellulose (HPC) and polyvinyl alcohol (PVA)-based composites were tailored by solvent- and film-casting methods, respectively. After 2, 4, 6 and 8 passes through high-pressure homogenizer, the tensile strength of the nanopapers were extremely high and increased linearly depending upon the pass number. Chemical modification of 1H, 1H, 2H, 2H-perfluorodecyl-triethoxysilane (PFDTES) on the nanopapers significantly increased the mechanical strength and water repellency. The reinforcement of 1, 3, and 5 wt% CNF to HPC and PVA resins also improved the mechanical properties of the both composites.

• Food Science of Animal Resources
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• v.32 no.2
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• pp.220-227
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• 2012

The objective of this study was to investigate the influence of emulsion processing with various homogenization treatments on the physical properties of nanoparticles. For the manufacturing of nanoparticles, by taking the emulsion-diffusion method, various coating materials, such as gum arabic, hydroxyethyl starch, polycarprolactone, paraffin wax, ${\kappa}$-carrageenan and emulsifiers like Tween$^{(R)}$60, Tween$^{(R)}$80, monoglyceride and Pluronic$^{(R)}$F68, were added into the emulsion system. Furthermore, the various speeds (7,000 rpm to 10,000 rpm), and times (15 s to 60 s) of homogenization were treated during the emulsion- diffusion process. NEO II homomixer was the most effective homogenizer for making nanoparticles as 51 nm ($D_{10}$) and 26 nm ($D_{50}$). To manufacture smaller nanoparticles, by using NEO II homomixer, 10,000 rpm of agitation speed, polycaprolactone as coating material, and Pluronic$^{(R)}$F68 as an emulsifier were the optimum operating conditions and components. For the stability of nanoparticles for 7 days, $20^{\circ}C$ of storage temperature was appropriate to maintain the particle size. From these results, the type of homogenizer, homogenization speed, homogenization time and storage temperature could affect the particle size. Moreover, type of coating materials and emulsifier also influenced the size and stability of the nanoparticles.