• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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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.

• Transactions of the Korean hydrogen and new energy society
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• v.15 no.2
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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.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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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.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.12
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• pp.1797-1801
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• 2011

Two brown rice samples differing in amylose content, 20.1 (normal) and 7.3% (low amylose) were milled by different milling methods, and their physicochemical properties were tested. Particle size of brown rice flour prepared by dry milling using a pin mill (DM) was lower than that prepared by wet milling using a roll mill (WM). Particle size was further reduced by successive dry milling of the flour after wet milling and drying (WM/DM). Damaged starch contents in the wet milled brown rice flour were 14.6 and 15.6% for the normal and low amylose samples, respectively, whereas they were only 4.2 and 4.8% for the dry milled samples. WM/DM method resulted in a lower damaged starch (%) than DM, despite a reduced flour particle size. Water absorption index (WAI) of the brown rice flour was the lowest after WM/DM, and the water solubility index (WAI) was higher in the order of DM, WM/DM, and WM. Brown rice flour with normal amylose content appeared to have significantly higher pasting viscosities, as determined using a Rapid Visco Analyzer (RVA). Compared to dry milled brown rice flour, wet milled brown rice flour showed lower peak viscosity and higher final viscosity, resulting in increased setback value.

• Korean Journal of Food Science and Technology
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• v.32 no.1
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• pp.75-81
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• 2000

The processing properties for rice bread were examined using eight kinds of endosperm mutant rice. The varietal differences among eight kinds of endosperm mutant rice having the respective sugar contents and amylose contents were studied. The water absorptions of these eight cultivars were observed to have significant differences among the cultivars, revealing the water absorption ability of Shrunken(shr.) was 61.5%, and that of Punchilmi(fl) was 48.4%. In addition, the experiments using Whachungbyeo, Nampungbyeo and their mutant cultivars showed that the maximum water absorption was tend to be negatively correlated with the amylose content of each rice cultivars. This study also showed that the rice breads made by dry-milling was better in shape, mechanical properties(hardness, springiness, adhesiveness, chewiness) and texture tested using sensory evaluation than that made by wet-milling.

• Applied Biological Chemistry
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• v.28 no.3
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• pp.115-123
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• 1985

The milling characteristics of barley of various moisture content were investigated using Brabender Grain Hardness Tester (GHT) to set up the optimum conditions of dry milling process. The optimum GHT clearance were 1/0-1/10 for-10+12 mesh particles, 0/5-0/15 for-12+18 mesh, and 0/-15 for -18 mesh. The grain hardness of barley kernel increased with moisture content and the grindability, on the other hand, decreased. The consumed electric energy in milling increased with moisture content and showed the maximum value at the moisture content of 14.04%. The optimum conditions of dry milling of barley were 0/-5 GHT clearance and 12.80% moisture content and the consumed electric energy was 92.41Kwh for the production of 1,000kg of -18 mesh particles.

• Industrial Engineering and Management Systems
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• v.9 no.3
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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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• 2004.08a
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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.

• Resources Recycling
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• v.11 no.4
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• pp.3-10
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• 2002

The characteristics of dry and wet milled powder prepared by 1 cycle OREOX (oxidation and reduction of oxide fuels) treatment were investigated using the simulated spent fuel pellet. Sintered pellets simulating spent nuclear fuel burned in reactor were fabricated from $UO_2$ powder using as a starting material in fabrication of nuclear fuel. The 1 cycle OREOX-treated powder was prepared by only one path of oxidation md reduction of the simulated pellet. Powder having average particle size of less than 1 $\mu\textrm{m}$ could be easily obtained by dry milling, but not be achieved by wet milling. And, specific surface area of dry milled pow-der was higher than that of wet milled powder. Dry milled powder formed loose agglomerate, while wet milled powder showed the shape of irregular and angular particles. Dry milled powder provided higher green density, resulting in higher sintered density of higher than 95% TD and average grain size of larger than 8 $\mu\textrm{m}$ satisfying the standard specification of sintered pellets.

• Journal of Powder Materials
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• v.10 no.6
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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%.