• 한국식품영양과학회지
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• 제23권4호
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• pp.686-697
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• 1994

The hardness of hard red winter (HRW) wheat had an effect on the yield of farina , as it positively correlated with the coarse fraction (over 34W) and negatively correlated with the flour fraction from farina milling. But it did not show any significances on flour milling from the micromilling process. The flour yields was better correlated with the break flour fraction (r=0.730 than with reduction flour (r=0.27). The farina yield was controlled by a fraction over 34W (coarse granule0. Protein was the most important single factor for the quality of cooked farina spaghetti, but not for flour milling or farina milling. On the other hand, hardness was important in the production of farina milling , whereas it did not govern spaghetti cooking quality, Environmental factors affected the quality of cooked spaghetti as much as varieties of HRW wheats. The quality of cooked farina spaghetti generally correlated with the protein in the location composites of wheats. Higher protein content wheats showed better spaghetti cooking quality.

• Carbon letters
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• 제26권
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• pp.11-17
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• 2018

Milled carbon fiber (mCF) was prepared by a ball milling process, and X-ray diffraction (XRD) diffractograms were obtained by a $2{\theta}$ continuous scanning analysis to study mCF crystallinity as a function of milling time. The raw material for the mCF was polyacrylonitrile-based carbon fiber (T700). As the milling time increased, the mean particle size of the mCF consistently decreased, reaching $1.826{\mu}m$ at a milling time of 18 h. The XRD analysis showed that, as the milling time increased, the fraction of the crystalline carbon decreased, while the fraction of the amorphous carbon increased. The (002) peak became asymmetric before and after milling as the left side of the peak showed an increasingly gentle slope. For analysis, the asymmetric (002) peak was deconvoluted into two peaks, less-developed crystalline carbon (LDCC) and more-developed crystalline carbon. In both peaks, Lc decreased and $d_{002}$ increased, but no significant change was observed after 6 h of milling time. In addition, the fraction of LDCC increased. As the milling continued, the mCF became more amorphous, possibly due to damage to the crystal lattices by the milling.

• 한국식품과학회지
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• 제31권5호
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• pp.1371-1377
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• 1999

본 연구에서는 백미의 돌연변이 억제 활성 물질의 분포 및 정제를 위한 기초자료를마련하고, 세포외 작용기작의 하나인 항산화활성과의 상관성을 살펴보기 위해 일품벼를 도정분획별로 분획한 다음 돌연변이 억제활성 및 항산화 활성을 조사하였다. Salmonella typhimurium reversion assay를 이용하여 Trp-P-2로 유도된 변이원성에 대해 도정분획별 돌연변이 억제활성을 살펴본 결과, 미강에서는 외층으로 갈수록. 백비에서는 내층으로 갈수록 더 강한 돌연변이 억제 활성을 보였다. 과산화물가(POV) 측정에 의한 항산화 활성은 배아와 미강 부분이 백미보다 더 활성이 강한 것으로, TBA치로 측정한 항산화 활성은 백미의 경우 $6{\sim}20%$로 낮았으며 배아, 미강, 배유는 거의 활성이 없었다. 전자공여능(EDA) 측정으로 살펴본 항산화 활성은 배아(45%), 미강$(35{\sim}40%)$보다는 백미$(41{\sim}65%)$에서, 도정 율이 낮을수록 더 강한 활성을 나타내었다. 돌연변이 억제활성은 전자공여작용과는 양의 상관성(r=0.609)을 과산화물가와는 음의 상관성(r=-0.471)을 나타내었고 TBA치 측정에 의한 항산화 활성과는 유의적인 상관성이 없었다. 도정분획별 페놀산 및 SH함량은 미강 및 배아가 백미에 비해 높았고, 백미에서는 내층으로 갈수록 함량이 낮아 돌연변이 억제활성과 음의 상관성을 보였다.

• 한국식품영양과학회지
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• 제25권5호
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• pp.721-726
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• 1996

쌀의 영양, 가공 및 저장 등 효율적인 활용을 위한 기초자료의 제시를 목적으로 제분 분획(milling fraction) 별로 시료를 제조하여 지방산과 페놀산 함량을 조사하였다. 쌀의 주요 지방산은 palmitic, oleic 및 linoleic으로서, 배아는 palmitic 20.0%, oleic 33.3% 및 linoleic 43.0%의 함량을, 미강은 palmitic 17.3%, oleic 45.1% 및 linoleic 34.5%의 함량을, 백미는 palmitic 23.4%, oleic 26.2% 및 linoleic 46.4%의 함량을 나타내었다. 제분 분획별 지방산 함량은 미강의 경우 oleic은 외층일수록, linoleic내층일수록 함량이 높았다. 백미의 경우 oleic acid는 외층일수록, palmitic acid, linoleic acid, stearic acid 및 linolenic acid는 내층일수록 함량이 높았다. 페놀산 함량은 미강의 경우 유리 페놀산 321.0mg%, 페놀산 에스터 299.7mg% 및 불용성 결합형 페놀산 212.4mg%이었다. 백미는 유리 페놀산 118.omg%, 불용성 결합형 페놀산 56.0mg%이었고 페놀산 에스터는 추출되지 않았다. 페놀산의 구성성분은 미강의 경우 ferulic acid의 함량이 86.2%로 가장 높았으며 sinapic 및 syringic acid는 35.7~36.6%, p-coumaric acid는 16.7%이었고 vanillic acid는 미량 검출되었다. 백미는 ferulic acid 12.3%, sinapic acid 4.1%, p-coumaric acid 3.6%의 함량을 나타내었다. 제분 분획별로 조사한 총 페놀산의 함량은 배아가 0.18%로 가장 높았으며 미강은 외층일수록 함량이 높았고 백미는 미량존재 하였던 성분이 분획에 따라 함량이 분산되어 검출되지 않았다.

• 한국분말재료학회지
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• 제25권2호
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• pp.126-131
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• 2018

In the present study, we investigate the effects of milling time and the addition of a process control agent (PCA) on the austenite stability of a nanocrystalline Fe-7%Mn alloy by XRD analysis and micrograph observation. Nanocrystalline Fe-7%Mn alloys samples are successfully fabricated by spark plasma sintering. The crystallite size of ball-milled powder and the volume fraction of austenite in the sintered sample are calculated using XRD analysis. Changes in the shape and structure of alloyed powder according to milling conditions are observed through FE-SEM. It is found that the crystallite size is reduced with increasing milling time and amount of PCA addition due to the variation in the balance between the cold-welding and fracturing processes. As a result, the austenite stability increased, resulting in an exceptionally high volume fraction of austenite retained at room temperature.

• 한국세라믹학회지
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• 제23권4호
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• pp.35-40
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• 1986

The production process of a fine size fraction of Korean kaolin by ball milling is studied in this paper by analyzing the size distribution the size distribution of products with the Rosin-rammle formular and the rate process of cumulative size fractions with Alyavdin-Chujyo's formular. The size distribution is found to be divided in three regions a coarser part influenced by feed size an intermediate part where the size distribution shows a clear straight line relationship on Rosin-Rammler chart and the finest part with the ultimate limit of fineness by ball milling. Alyavdin-Chujyo's relationship is found to be valid over a very wide range of milling conditions. For different feed sizes the Alyavdin-Chujyo's relationship gives a group of straight lines with a common intersection point which can be defined as the limiting point of the persistent component region.

• 자원리싸이클링
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• 제20권6호
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• pp.37-42
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• 2011

구리관의 절단 공정에서 구리 칩 스크랩이 발생해왔다. 분쇄에 의하여 구리칩 스크랩을 분말화하는 가능성이 연구되었다. 본 연구에서는 로드 밀링, 수평식 볼밀링과 같은 두 가지 타입의 분쇄 방식이 적용되었다. 구리 칩은 로드 밀링에 의하여 분말 형태로 분쇄될 수 없었다. 반면에 36시간 이상 수평식 볼밀링에 의하여 구리칩은 분말로 변화하였다. 수평식 볼밀링에 의한 구리 칩의 분말로 재활용이 가능하였고 48시간 동안 밀링된 원료중 $75{\sim}150{\mu}m$ 범위의 분말은 25.3%이였다.

• 한국초전도ㆍ저온공학회논문지
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• 제21권1호
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• pp.18-24
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• 2019

This study was carried out to investigate the effect of milling of boron (B), which is one of raw materials of $MgB_2$, on the critical current density ($J_c$) of $MgB_2$. B powder used in this study is semi-amorphous B (Pavezyum, Turkey, 97% purity, 1 micron). The size of B powder was reduced by planetary milling using $ZrO_2$ balls (a diameter of 2 mm). The B powder and balls with a ratio of 1:20 were charged in a ceramic jar and then the jar was filled with toluene. The milling time was varied from 0 to 8 h. The milled B powders were mixed with Mg powder in the composition of (Mg+2B), and the powder mixtures were uniaxially pressed at 3 tons. The powder compacts were heat-treated at $700^{\circ}C$ for 1 h in flowing argon gas. Powder X-ray diffraction and FWHM (Full width at half maximum) were used to analyze the phase formation and crystallinity of $MgB_2$. The superconducting transition temperature ($T_c$) and $J_c$ of $MgB_2$ were measured using a magnetic property measurement system (MPMS). It was found that $B_2O_3$ was formed by B milling and the subsequent drying process, and the volume fraction of $B_2O_3$ increased as milling time increased. The $T_c$ of $MgB_2$ decreased with increasing milling time, which was explained in terms of the decreased volume fraction of $MgB_2$, the line broadening of $MgB_2$ peaks and the formation of $B_2O_3$. The $J_c$ at 5 K increased with increasing milling time. The $J_c$ increase is more remarkable at the magnetic field higher than 3 T. The $J_c$ at 5 K and 4 T was the highest as $4.37{\times}10^4A/cm^2$ when milling time was 2 h. The $J_c$ at 20 K also increased with increasing milling time. However, The $J_c$ of the samples with the prolonged milling for 6 and 8 h were lower than that of the non-milled sample.

• 한국분말재료학회지
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• 제7권1호
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• pp.27-34
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• 2000

The fabrication process and mechanical properties of SiC particle prefrrms with high volume fraction ranged 50∼71% were investigated to make metal matrix composites for possible applications as heat sinks in electronic packares. The SiC particle preforms with 50∼71vol% of reinforcement were fabricated by a new modified process named ball milling and pressing method. The SiC particle performs were fabricated by ball milling of SiC particles with single sized of 48${\mu}$m in diameter or two different size of 8${\mu}$m and 48${\mu}$min diameter, with collodal SiO2 as inorgnic binder in distilled water, and the mixed slurries were cold pressed for consolidation into final prefom. The compressive strengths og calcined SiC particle prefoms increased from 20MPa to 155MPa with increasing the content of inorganis binder, temperature and time for calcination. The increase of compressive strength of SiC particle bridge the interfaces of two neighboring SiC particles.

• Plant Resources
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• 제4권3호
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• pp.140-146
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• 2001

This study was conducted to investigate the $\beta$-glucan contents and their characteristics of winter cereals according to particle sizes and milling recoveries. Sieved fractions differed in their average contents of $\beta$-glucans, and the coarse fraction had higher contents of $\beta$-glucan than finely milled fractions. In all winter cereals, the $\beta$-glucan contents of raw flours were higher than those of their brans, and the highest $\beta$-glucan contents of every cereals were observed at 100 mesh > or 100-140 mesh fractions except the Chalssalbori fractions which showed the higest $\beta$-glucan contents (12.9%) at 140-200 mesh fraction. As compared with the $\beta$-glucan content of Chalbori among the various milling recoveries, the $\beta$-glucan was distributed more evenly throughout the endosperm but $\beta$-glucan content in bran of Chalbori was only 1.5%. However, $\beta$-glucan content of Chalssalbori (hull-less waxy barley) was the highest in the subaleurone region (8.2%) and declined slightly toward inner layers of grain. This results suggest that $\beta$-glucan distribution between high (Chalbori) and low $\beta$-glucan barley (Chalssalbori) may explain the difference in milling performance of barley. On the other hand, $\beta$-glucan contents of two rye varieties (Chilbohomil, Chunchoohomil) were lower than those of two waxy barley varieties, and the higest $\beta$-glucan contents were observed at the 60% milling recoveries. In all winter cereals, the L-values (lightness) of raw flours were higher than those of brans. And the L-values of barley varieties were higher than those of oat and rye varieties. As the particle sizes and milling recovery ratios were decreased, the L-value were increased. The a-values (redness) in brans of every winter cereals were higher than those of every particle size flours and every milling ratio fractions, and this tendency was observed in the b-values (yellowness) of every particle size of cereal flours. The L and b-value of barley, the b-value of oat, and L, a, b-value of rye have the significant relationship with the $\beta$-glucan contents, respectively. This results represent the fact that $\beta$-glucans affected the color of the flours and pounded grains of winter cereals.