• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.286-286
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• 2017

We conducted to compare the characteristics of rice flours according to the different milling processes. Five rice varieties (Oryza sativa L.) with different amylose content were prepared by wet and dry milling processes. The moisture contents of wet-milled rice flours (WMR) was mostly three-time higher than those of dry-milled flours (DMR). Water absorption index (WAI), water solubility index (WSI) and swelling power (SP) increased in proportion to temperature ($50-90^{\circ}C$). WAI, WSI, SP of DMR showed higher value than those of WMR. Baeokchal (BOC) which is waxy rice cultivar was significantly high level of WSI. Pasting properties of DMR except BOC cultivar resulted in higher peak viscosity, trough viscosity, final viscosity and Setback. The levels of resistant starch in the four cultivars except Dodamssal (DDS) were under 1% irrespective of Milling processes, whereas the resistant starch contents of DMR and WMR in DDS was 9.18 and 6.27, respectively. Damaged starch content of WMR were less than those of DMR, moreover, negative correlation was observed between amylose content and damaged starch of rice cultivars. These results suggest that the properties of rice flour varied depending on the milling methods and varieties, and it could be a reference for selecting the appropriate processing purposes.

• 한국수소및신에너지학회논문집
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• 제15권2호
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• pp.98-107
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• 2004

Modified Ni/YSZ cermets for high temperature electrolysis were synthesized by dry or wet mechanical alloying methods. The Ni/YSZ composit particle was directly fabricated from the ball milling of Ni and YSZ powder or obtained from the reduction of NiO/YSZ particle after the ball milling of NiO and YSZ. In the case of the NiO/YSZ composite particle, the dry milling increased the average particle size whereas the wet milling decreased the size. The dry milling showed that fine YSZ particles were distributed over large Ni surfaces while Ni and YSZ particles similar in size were well mixed in the wet milling method. These features were the same in the Ni/YSZ composite particle prepared from Ni and YSZ powders. The electrical conductivity of the wet-milled Ni/YSZ cermet showed the highest value of $2{\times}10^2S/cm$ among the specimens and this value was increased to $1.4\times10^4S/cm$ after the sintering at $900^\circ{C}$ for 1 h.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.648-649
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• 2006

The dry-milling technique was used for mixing and crushing oxides and graphite powders. The ratio of ball-to-powder was 30:1 and argon gas was filled in jar. The excess carbon was $10{\sim}20wt%$ of the stoichiometric amount. The dry-milling was carried for 20 hours. The mixed powders were reduced and carburized at $900{\sim}980^{\circ}C$ for 3 hours flowing Ar gas in tube furnace. The dry-milled powders showed the wide diffraction patterns of X-ray. The reactions of reduction and carburization were completed in 3 hours at $980^{\circ}C$. After the reactions, the mean size of WC particles was about 200 nm. The content of free carbon in WC/Co mixed powders was less as the reaction temperature increased.

• 한국식품영양과학회지
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• 제40권12호
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• pp.1797-1801
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• 2011

아밀로오스 함량에 차이가 있는 일반 멥쌀 현미(아밀로오스 20.1%)와 저아밀로오스 현미(아밀로오스 7.3%)를 제분 방법을 달리하여 현미가루로 제조한 후 제분방법별 현미가루의 이화학적 특성을 비교 조사하였다. Pin mill로 건식제분 한 현미가루의 입자크기가 수침후 roll mill에 의해 습식제분 한 현미가루에 비해 작았고 입자크기는 습식제분 하여 건조한 현미가루를 2차 건식 재분쇄하는(습식/건식) 제분방식에 의해 더 감소하였다. 현미가루의 전분손상도는 건식제분 현미가루가 14.6~15.6%로 습식제분 4.2~4.8%에 비해 현저하게 높았으나 습식/건식제분이 그대로 건식제분 하는 방법에 비해 입자크기가 미세해지면서 현미가루의 전분손상도는 줄여줄 수 있는 것으로 나타났다. 현미가루의 수분흡수지수는 습식/건식 현미가루에서 가장 낮았으며 수분용해도지수는 건식>습식/건식>습식제분 순이었다. 습식제분 한 현미가루가 건식제분보다 최고점도가 낮은 반면에 paste의 최종점도는 증가하여 setback은 증가하는 경향을 보였다. 제분방법별 일반 현미가루의 평균 최고점도, trough, breakdown, 최종점도, setback이 저아밀로오스 현미가루에 비해 훨씬 높게 나타났으며 전분의 노화 정도에 서로 차이가 있을 것으로 예측되었다.

• 한국식품과학회지
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• 제32권1호
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• pp.75-81
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• 2000

아밀로오스함량, 당함량, 전분입자의 형태 등에 차이를 보이는 8품종 변이체 벼들의 쌀빵가공성에 대한 제분방법(습식 및 건식)의 차이에 대해서 검토하였다. 이들 8품종의 최대수분흡수량은 품종에 따라 상당히 차이가 있어 shr.은 61.5%, 분질미는 48.4%였고, 화청벼 남풍벼 및 그들의 변이체들은 아밀로오스 함량이 낮은 품종의 쌀일수록 최대 수분흡수량은 증가하고 있었다. 건식제분에 의해서 제조한 쌀빵이 성형성, 기계적인 물성(경도, 탄력성, 응집성. 씹힘성) 및 관능검사에 의한 질감의 면에서 습식제분의 경우보다 우수하였다.

• Applied Biological Chemistry
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• 제28권3호
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• pp.115-123
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• 1985

보리의 건식제분공정을 확립키 위하여 수분함량 별 보리의 제분특성을 Brabender Grain Hardness Tester를 사용하여 조사하였다. 분말의 입자크기 별 적정 GHT간극은 -10+12mesh는 $1/0{\sim}1/10$, -12+18mesh는 $0/5{\sim}0/15$, -18mesh는 0/-15이었다. 수분함량에 따른 파쇄성은 수분함량이 감소할수록 증가하였으며 곡립경도는 반대양상을 나타내었다. 제분에 소요되는 에너지는 GHT간극이 작을수록, 수분함량이 증가할수록 큰값을 보였고 수분함량 14.04%에서 최대치를 나타내었다. 건조 소요에너지를 감안할 때 보리의 최적 건식제분조건은 수분함량 12.80%에서 GHT간극 0/-5일 때이었고 이때 1,000kg의 -18mesh 입자를 생산하는데 소요되는 에너지는 92.41kwh이었다.

• Industrial Engineering and Management Systems
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• 제9권3호
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• pp.242-250
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• 2010

For economical and environmental reasons, the aim of this research is hence to monitor the cutting conditions with the dry cutting, the wet cutting, and the mist cutting to obtain the proper cutting condition for the plain carbon steel with the ball end milling based on the consideration of the surface roughness of the machined parts, the life of the cutting tools, the use of the cutting fluids, the density of the particles of cutting fluids dispersed in the working area, and the cost of cutting. The experimentally obtained results of the relation between tool wear and surface roughness, the relation between tool wear and cutting force, and the relation between cutting force and surface roughness are correspondent with the same trend. The phenomena of surface roughness and tool wear can be explained by the in-process cutting forces. The models of the tool wear with the cutting conditions and the cutting times are proposed to estimate the tool cost for the different cooling strategies based on the experimental data using the multiple regression technique. The cutting cost is calculated from the costs of cutting tool and cutting fluid. The mist cutting gives the lowest cutting cost as compared to others. The experimentally obtained proper cutting condition is determined based on the experimental results referring to the criteria.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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• pp.555-557
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• 2004

We report the effect of the particle size (D50) and PSD (Particle Size Distribution) of glass frit on the transparency of transparent dielectric layer of PDP. The milling efficiency of wet milling with water was the best among the dry milling, wet milling with IPA and wet milling with water. The transparency increased with the reduction of particle size of glass frit as the milling time increased. Also the transparency changed by the PSD of glass frit. Glass frits of broad PSD showed high transparency compared with the glass frits of sharp PSD.

• 자원리싸이클링
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• 제11권4호
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• pp.3-10
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• 2002

핵연료 원료인 $UO_2$ 분말을 사용해 원자로에서 연소된 사용후 핵연료 소결체를 모의 제조하여 1회 산화ㆍ환원처리하여 분말로 만든 후, 건ㆍ습식 attrition 분쇄에 따른 분말의 특성 및 소결성을 조사하였다. 분쇄에 의한 분말의 평균입자크기는 건식분쇄의 경우에는 1 $mu extrm{m}$ 이하인 미분말이 쉽게 생성되었으나, 습식분쇄에서는 그 이상의 분말만이 생성되었다. 그리고 분쇄분말의 비표면적은 건식분쇄한 경우가 습식분쇄한 경우 보다 높았다. 분말의 미세구조는 건식분쇄에 의해서는 느슨한 응집체가 형성되었으며, 습식분쇄 분말은 압분성이 낮은 불규칙적이고 각진 입자형태를 나타내었다. 건식분쇄에 의해서 압분체 밀도는 크게 증가하며 소결체 요구 조건을 만족하는 이론밀도의 95%이상이 되고 평균 결정립 크기가 8 $\mu\textrm{m}$이상인 소결체를 얻을 수 있었다.

• 한국분말재료학회지
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• 제10권6호
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• pp.415-421
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• 2003

The study for producing the flake powders by milling of aluminum foil and gas atomized powders was carried out. The effects of lifter bars on the ball motions and milling of aluminum foils were also investigated. The aluminum foils were laminated each other, elongated, fragmented into small foils and finally formed into the flake powders during the dry ball-milling. The spherical atomized-powders were milled to coarse flake powders with high aspect ratio and then changed to fine flake powders with lower aspect ratio. Even though long times were required for making flake powders by milling of foils, the water covering areas of them were higher than those of powders milled using gas-atomized powders, suggesting aluminum foils were more plastically deformed by micro-forging. On the other hand, as the number of lifter bars increased, the necessary rotation speeds of milling jar for cascading mode and cataracting mode decreased drastically. It was possible to achieve same quality of milled flake powder by using the lifter bars under the lower milling speeds. The painting test showed that the appearance of painted surface was good and optimum content range of aluminum paste in car paint to maximize the degree of gloss was 3-5%.