• 동아시아식생활학회지
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• 제20권1호
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• pp.77-83
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• 2010

The study was conducted to investigate the effect of particle size on the physicochemical properties of egg yolk-rice porridge. The pH of egg yolk-rice porridge was decreased when compared to that of the control, while the lightness and yellowness was increased as the rice particle size increased. The viscosity of whole particle egg yolk porridge was highest among the three porridges at $40^{\circ}C$. The protein content of the egg yolk-rice porridge was increased three-fold, when compared to that of the rice porridges. The total amino acid content of egg yolk-rice porridge was 1,500.6 mg/100 g, while that of rice was 1,147.5 mg/100 g. The Lys and Thr content of the amino acid content of egg yolk-rice porridge were also increased. Sensory evaluation results revealed that the half particle size rice egg yolk-rice porridge had the highest scores in color, taste and over-all preference. Based on these results, the half particle size egg yolk-porridge had good quality with respect to both the physicochemical and nutritional properties.

• 한국전기전자재료학회논문지
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• 제37권3호
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• pp.292-296
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• 2024

In this study, Iron (III) oxide-hydroxide (δ-FeOOH) was successfully synthesized using hydrogen peroxide (H₂O₂) as an oxidizing agent. The synthesis of δ-FeOOH was carried out by controlling the amount of H₂O₂, and pure δ-FeOOH was successfully synthesized in ranges from 0.2 mL to 0.6 mL of H₂O₂. The size of the synthesized δ-FeOOH particles was compared by controlling the amount of oxidant H₂O₂. The average particle size of the synthesized pure δ-FeOOH particles increased from 875.1 nm to 897.2 nm as the amount of H₂O₂ was increased. The optical properties of δ-FeOOH synthesized under these specific conditions were investigated. All δ-FeOOH showed a similar trend of increasing and decreasing light absorption from 800 nm to 400 nm, although there was a slight difference in the amount of light absorption, with the largest amount of light absorption at 410 nm. The band gap energy of δ-FeOOH through the Tauc plot method was about 2.1~2.2 eV when H₂O₂ was 0.2~1.4mL. With a sufficient small particle size, simple control of that particle size, and a small band gap energy enough to absorb light in the visible spectrum, δ-FeOOH could be useful in a variety of applications, including photoelectrochemistry and battery electrodes.

• 제어로봇시스템학회논문지
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• 제6권6호
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• pp.447-453
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• 2000

Using the scattering theory of laser light, we analyze the particle sizing method. The scattered profile measured by the photodetector is sampled, scale conditioned by a 32 channel analog-to-digital converter, and is analyzed with the transform matrix from the light energy signals to the weights of the particle sizes. The particle size distribution is classified using the Hopfield neural network method as well as the conventional nonnegative least square method.

• 한국응용과학기술학회지
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• 제23권1호
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• pp.1-11
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• 2006

The W/O emulsion was formed by mixing hydrophobic nonion surfactants of span 80 and tween 60 with kerosine, and by adding sodium silicate aqueous solution. Precipitating the W/O emulsion by sodium bicarbonate resulted in spherical silica particles. Shape and size distribution of silica particles were observed. The particles were spherical and they have narrow size distribution. Particle sizes were 9.29, 7.39 and $5.73\;{\mu}m$ at homogenizer speed of 2500, 3000, and 3500 rpm, respectively. The particle size was decreased by increasing agitation speed due to the formation of emulsion droplet. At fixed agitation speed, absorbed paraffin oil weight were measured and the $SiO_2/Na_2O$ mole ratio effects on particle size were investigated. Particle size was decreased by increasing the mole ratio of $SiO_2/Na_2O$.

• 한국재료학회지
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• 제12권10호
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• pp.803-808
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• 2002

Nickel powders were prepared from nickel chloride solution by wet reduction process, and the size control of the particles was investigated with reactant concentration, dispersant agent, and the addition of ethanol as an organic solvent in NiCl$_2$ aqueous solution. The size of the particle decreased with the increase of nickel chloride concentration. Their average particle size were 1.9$\mu\textrm{m}$, 1.6$\mu\textrm{m}$ and $1.5\mu\textrm{m}$ with 0.5M, 0.8M and 1.0M of nickel chloride concentration respectively. The spherical particle was easily controlled by the addition of ethanol as an organic solvent. Especially, in 30 vol% of ethanol, the average particle size and specific surface area were about 0.2$\mu\textrm{m}$ and 8.98m$^2$/g, respectively.

• 멤브레인
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• 제6권3호
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• pp.166-172
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• 1996

본 연구에서는 원하는 입자크기가 폴리부타디엔 라텍스를 제조하는 방법으로 공정조절이 쉽고 균일한 입자를 얻을 수 있는 막유화법을 이용하였으며, 유화제의 종류와 양, 첨가제의 양, 압력 등을 변수로 하여 실험을 행하였다. 제조된 라텍스의 입자크기와 분포를 분석하였으며, homogenizer를 이용한 직접유화법의 결과와 비교하였다. 또한 막투과 모델을 고찰하기 위하여 Harkins-Brown 식에 의해 이론적인 drop의 크기를 계산하였다. 실험결과 물대비 0.2 wt% 이상의 유화제 함량에서 안정한 라텍스를 얻을 수 있었고, 입자크기를 결정하는 가장 핵심적인 인자는 막표면의 기공 크기임을 알 수 있었다.

• 상하수도학회지
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• 제18권5호
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• pp.673-679
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• 2004

Particle breakthrough can occur by either the breakoff of previously captured particles (or flocs) or the direct passage of some influent particles through the filter. Filtration experiments were performed in a laboratory-scale filter using spherical glass beads with a diameter of 0.55 mm as collectors. A single type of particle suspension (Min-U-Sil 5, nearly pure $SiO_2$) and three different destabilization methods (pH control, alum and polymer destabilization) were utilized. The operating conditions were similar to those of standard media filtration practice: a filtration velocity of 5 m/h. To assess the possibility of particle detachment during the normal filtration, a hydraulic shock load (20% increase of flow rate) was applied after 4 hours of normal filtration. The magnitude of particle detachment was proportional to the particle size for non-Brownian particles. At the same time, less favorable particles, i.e., particles with larger surface charge, were easily detached during the hydraulic shock load. Therefore, proper particle destabilization before filtration is crucial for maximum particle removal as well as minimum particle breakthrough.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회B
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• pp.3168-3172
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• 2007

As the minimum feature size decreases, control of contamination by nanoparticles is getting more attention in semiconductor process. Cleaning technology which removes nanoparticles is essential to increase yield. A reference wafer on which particles with known size and number are deposited is needed to evaluate the cleaning process. We simulated particle trajectories in the chamber by using FLUENT and designed a particle deposition system which consists of scanning mobility particle sizer (SMPS) and deposition chamber. Charged monodisperse particles are generated using SMPS and deposited on the wafer by electrostatic force. The experimental results agreed with the simulation results well in terms of particle number and deposition area according to particle size, flow rate and deposition voltage.

• 폴리머
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• 제26권3호
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• pp.307-315
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• 2002

폴리스티렌의 취약한 성질을 개선한 내충격정 폴리스티렌 (HIPS)의 내충격성에 영향을 주는 요소는 분산된 고무상 입자의 크기 및 입도분포, 분자량, 형태구조, 그래프트율 등이다. 이에 따라 HIPS의 물성은 영향을 받으므로 이를 조절하거나 파악하는 것은 중요하다. 본 연구에서는 HIPS의 벌크-용액중합에서 용매함량이 고무입자의 형태구조 및 입도분포, 최종 물성에 미치는 영향에 대하여 고찰하였다. 먼저 중합 진행에 따른 분산상의 입도분포를 측정함으로써 상역전 현상의 변화 추이를 파악하여 전중합 시간을 결정하였다. 중합시 분산용매는 적절한 양에 도달하기 전까지는 고무입자의 크기가 증가하였으며, 그 후에는 점차적으로 감소하였다. 고무상의 형태구조는 분산용매가 증가함에 따라서 그래프트율이 증가하는 형태구조로 바뀌는 것으로 사료된다. 분산용매가 첨가됨에 따라 유변물성 및 인장물성이 취약해졌는데, 이는 분산용매에 의한 사슬이동반응이 매트릭스상인 폴리스티렌의 분자량을 감소시킨 점과 잔류 용매의 존재 때문이었다. 하지만 내충격성은 분산입자의 크기가 증가한 경우 향상되는 경향을 보였다.

• Korean Chemical Engineering Research
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• 제56권3호
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• pp.370-375
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• 2018

본 연구에서는 생리활성물질 (+)-dihydromyricetin의 입자크기 감소를 위하여 친수성 고분자 물질을 첨가하여 분별침전을 수행하였다. 고분자 물질(HPMC 2910, PVP K90, PVA)이 첨가된 분별침전을 통해 (+)-dihydromyricetin 입자크기를 감소시킬 수 있었다. 특히 분별침전 시 HPMC 2910 (0.1%, w/v)을 첨가할 경우, 대조군에 비하여 입자크기가 $38-68{\mu}m$ (32-40%) 정도 감소하여 입자크기 감소에 가장 효과적이었다. 또한 (+)-dihydromyricetin침전물의 입자크기는 친수성 고분자 물질 첨가에 따른 침전용액의 제타전위 절대값에 반비례함을 알 수 있었다.