• Journal of Biosystems Engineering
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• 제31권1호
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• pp.33-38
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• 2006

This work was conducted to find the operating characteristics of an efficient wet grinding system designed to obtain fine rice husk ash powder. Once the rice husk was combusted and the thermal energy was recovered from the furnace, the ash was fed and pulverized in the grinding system resulting a fine powder to be used as a supplementary adding material to the portland cement. Grinding time (15, 30, 45 min), impeller speed (250, 500, 750 rpm), and mixed ratio (6.7, 8.4, 11.l, 20.9) were three operating factors examined for the performance of a wet-type stirred ball mill grinding system. For the operating conditions employed, mean diameter of fine ash powder, specific energy input, and grinding energy efficiency were in the range of $2.83{\sim}9.58{\mu}m,\;0.5{\sim}6.73kWh/kg,\;and\;0.51{\sim}3.27m^2/Wh$, respectively. With the wet-type stirred ball mill grinding system used in this study, the grinding energy efficiency decreased with the increase in total grinding time, impeller speed, and mixed ratio. The difference in specific surface area of powder linearly increased with logarithm in total number of impeller revolution and the grinding energy efficiency linearly decreased. Grinding time of 45 min, impeller speed of 500 rpm, and mixed ratio of 6.7 were chosen as the best operating condition. At this condition, mean particle diameter of the fine ash, grinding energy efficiency, grinding throughput, and specific energy input were $2.84{\mu}m,\;2.28m^2/Wh,\;0.17kg/h$, and 2.03kWh/kg, respectively. Wet fine grinding which generates no fly dust causing pollution and makes continuous operation easy, is appeared to be a promising solution to the automatization of rice husk ash grinding process.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 추계 학술발표회 논문집
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• pp.521-524
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• 2006

This study is about the production and properties of waste concrete powder that recycling aggregate is crushed to the waste concrete. We researched the generation and the disposal of recycled concrete powder. It is chemica] and physical features that is compared and analysis according to its production system and repeated crushing of time. Recycled concrete powder is more generated wet process than drying process. In addition, the more it is repeated crushing of time, the more recycled concrete powder is generated. Recycled concrete powder is discovered that wet process is larger of the specific area, lower density and particle size.

• Nuclear Engineering and Technology
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• 제35권4호
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• pp.299-308
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• 2003

Fabrication technique of $(Th,U)O_2$ pellets has been investigated. Powder mixtures of $ThO_2\;and\;UO_2$ were milled in two different ways-dry and wet milling. Milled powder was compacted and sintered to $(Th,U)O_2$ pellets. The wet-milled powder leads to a $(Th,U)O_2$ pellet having a high sintered density and uniform distribution of U and Th, compared to the dry-milled powder. The sintered density of a $(Th,U)O_2$ pellet tends to decrease by increasing the content of $ThO_2$. The thermal conductivity of $ThO_2\;and\;(Th,U)O_2$ pellets was measured by the laser flash method. The thermal conductivity of the $ThO_2$ pellet is higher than that of the $UO_2$ pellet, and the thermal conductivities of $(Th,U)O_2$ pellets containing $65wt\%\;and\;35wt\%\;ThO_2$ pellets are lower than that of the $UO_2$ pellet.

• 한국축산식품학회지
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• 제37권2호
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• pp.242-253
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• 2017

This study was performed to evaluate antioxidant activity of tomato powder extracted by various concentrations of ethanol (0, 25, 50, 75, 100%) and to evaluate the physicochemical properties and antioxidant activities of pork patties with ethanol extracted tomato (EET) powder. No differences in the contents of total of individual phenolic compounds including gallic acid and catechin, were observed among the treatments (p>0.05). Among the various concentrations, 50% and 75% EET powder showed the highest free radical scavenging and iron chelating activities (p<0.05). Lipid peroxidation was retarded in linoleic acid emulsion with the addition of 50% and 75% EET powder (0.1%). Based on the model study, five pork patties were actually manufactured; control patty, reference patty with 0.01% of butylated hydroxytoluene, patty with 1% of water extracted tomato (WET), and patties with 0.5 and 1.0% of EET. Addition of 1% WET and EET decreased pH value, and increased redness values of pork patties, as compared to the control (p<0.05). Pork patties with WET (1.0%) and EET (0.5% and 1.0%) had lower 2-thiobarbituric acid reactive substances values compared with control patties after 7 d of storage (p<0.05). Pork patties containing EET powder showed lower total bacterial and Enterobacteriaceae counts than control patties (p<0.05). In conclusion, WET and EET (50%) could be used as a natural antioxidant and antimicrobial agent in meat products.

• 한국식품저장유통학회지
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• 제10권2호
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• pp.187-191
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• 2003

검은버섯분말 3, 5, 7%를 첨가하여 국수를 제조한 후 품질을 분석해 련 결과 최고점도와 최종점도 및 노화도는 무처리보다 버섯첨가구에서 모두 낮은 값을 나타내었으며 첨가량이 증가할수록 낮아지는 경향을 나타내었다. 버섯분말첨가량이 증가함에 따라 수분흡수율은 약간 증가하였다. 색도는 버섯분말의 첨가량이 증가함에 따라 분말, 반죽, 국수등 모든 처리구에서 명도는 낮아졌으며, 적색도와 황색도는 증가하는 것으로 나타났다. 버섯국수 조리후 중량과 부피는 버섯분말 첨가량이 증가할수록 감소하였으며 국물의 탁도는 감소하였다. 조리면의 물성 측정 결과 버섯분말 첨가량이 증가함에 따라 경도와 부착성은 감소하였으며 응집성은 감소하였다. 조리한 국수의 관능검사 결과, 버섯분말 3∼5%첨가국수에서 높은 값을 나타내어 무첨가 국수보다 우수하였다.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 1998년도 제28회 추계학술대회
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• pp.221-226
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• 1998

The processing conditions for the mass production of platelet WS$_2$ lubricant powder were optimized. The mixture of tungsten and sulfur powders was sealed in a vacuum of 10$^{-3}$ torr and heat-treated at 850$\circ$C for 2 h. The internal pressure of reaction chamber was maintained at certain level by controlling the release valve automatically. The reaction product was the platelet WS$_2$ powder with an average size of 15 $\mu$m. The synthesized WS$_2$ powder was then coated on the wiper-blade of automobiles and the commercial deep-grooved ball bearing using wet and dry coating methods, respectively. High lubricity and wear resistance of wet coated wiper-blade were confirmed by the life test of 70,000 cycles. The life-time of the ball bearing assembled after WS$_2$ coating onto each part increased 50 times compared to the non-coated ball bearing.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.1102-1103
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• 2006

The pretreatment for substrate was carried out in change of gun pressure of $0.5\sim3.5$ bar using wet blasting. The size of $Al_2O_3$ powder was about $50{\sim}150{\mu}m$. As the results, the surface roughness of cemented carbide substrate was improved with increment of gun pressure of wet blasting. A new surface layer was formed and Co particles were uniformly distributed over the entire surface after pretreatment. The adhesion of the pretreated substrate in same PVD-TiAlN film was improved and in approximately $Ra=90\sim120\;nm$ shown the best adhesion value.

• 한국분말재료학회지
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• 제19권3호
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• pp.182-188
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• 2012

In this study, fine cathode materials $Ni_3S_2$ and $NiS_2$ were synthesized using the simple, convenient process of mechanical alloying (MA). In order to improve the cell properties, wet milling processes were conducted using low-energy ball milling to decrease the mean particle size of both materials. The cells of Na/$Ni_3S_2$ and Na/$NiS_2$ show a high initial discharge capacity of 425 mAh/g and 577 mAh/g respectively using wet milled powder particles, which is much larger than commercial ones, providing some potential as new cathode materials for rechargeable sodium-ion batteries.

• 한국식품영양과학회지
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• 제43권4호
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• pp.530-536
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• 2014

밀가루에 현미가루와 수수가루의 비율을 달리하여 혼합하고 1회 죽염 2%를 첨가하여 3가지의 생면을 제조하였으며, 이를 밀가루와 정제염으로 만든 생면과 품질특성 및 in vitro 항산화 효과를 비교하였다. 품질특성 중 중량, 수분흡수율, 탁도는 현미가루와 수수가루를 첨가한 WBSN-b가 39.5 g, 97.4%, 0.62로 나타나 밀가루로 제조한 WN-p 측정 결과인 38.5 g, 92.5%, 0.59와 유사하였다. 탄력성은 WN-p(73.5%)와 WBSN-b(68.3%)에서 높았으며, 다음으로 WBN-b, WSN-b의 순으로 나타났다. 관능평가에서 전체적인 기호도는 WBSN-b가 6.4점으로 가장 높았고, WSN-b, WBN-b, WN-p는 6.1, 5.3, 5.3점이었다. 생면의 pH는 WBN-b는 7.4, WBSN-b는 7.5, WSN-b는 7.5, WN-p는 6.6로 1회 죽염과 현미가루와 수수가루를 첨가한 생면이 pH가 높게 나타났다. DPPH free radical 및 hydroxy radical 소거 효과에서는 현미가루와 수수가루를 10%씩 혼합한 생면 WBSN-b와 수수가루 20%를 혼합한 WSN-b가 높은 라디칼 소거능을 나타내었다. 본 연구 결과 현미가루와 수수가루를 각각 10%씩 그리고 1회 죽염 2%를 첨가한 생면이 밀가루로 제조한 생면의 품질특성에 가장 근접하였고, 기호면과 항산화 효과에서 가장 우수하였다.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.527-528
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• 2006

Nanostructured Alumina - 20 vol% 3YSZ composites powder were synthesized by wet-milling technique. The starting materials were a mixture of Alumina micro-powder and 3YSZ nano-powders. Nano-crystalline grains were obtained after 24 h milling time. The nano-structured powder compacts were then processed to full density at different temperatures by high-frequency induction heat sintering (HFIHS). Effects of temperature on the mechanical and microstructure properties have been studied. $Al_2O_3-3YSZ$ composites with higher mechanical properties and small grain size were successfully developed at relatively low temperatures through this technique.