• Title/Summary/Keyword: grains sizes

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$\beta$-glucan Contents and Their Characteristics of Winter Cereals According to Particle Sizes and Milling Recoveries

  • Kim, Sun-Lim;Park, Chul-Ho;Yu, Chang-Yeon;Hwang, Jong-Jin
    • Plant Resources
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    • v.4 no.3
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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.

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Improvement of Thermal Stability of In-situ Grown CoSi$_2$ Layer on Poly-Si Using Reactive Chemical Vapor Deposition (반응성 화학기상증착법에 의해 다결정실리콘 위에 직접성장된 $CoSi_2$ 층의 열적안정성의 개선)

  • Lee, Hui-Seung;Lee, Hwa-Seong;An, Byeong-Tae
    • Korean Journal of Materials Research
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    • v.11 no.8
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    • pp.641-646
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    • 2001
  • The $CoSi_2$ layers have been in-situ grown on undoped poly-Si by the reactive chemical vapor deposition of $Co({\Eta}^5-C_5H_5)(CO)_2$ at $650^{\circ}C$ and their thermal stabilities have been investigated in the temperature range of 800 to $1000^{\circ}C$. The $CoSi_2$ layer grown by the in-situ method had grains with large area of (111) plane, while grains with little area of (111) plane appeared on the $CoSi_2$ layer grown by the conventional two-step method where $CoSi_2$ formed first and transformed to $CoSi_2$. The thermal stability of the $CoSi_2$ layer grown by the in- situ process was improved by more than $100^{\circ}C$ higher than that of the $CoSi_2$ layer grown by the conventional two-step process. The $CoSi_2$ layer grown in situ on a large-grained Poly-Si was stable up to $950^{\circ}C$. The effect of stability improvement by the in situ growth was more pronounced when the grain sizes of the poly-Si substrate were small. The improved thermal stability of the in-situ grown $CoSi_2$ layer could be mainly due to the formation of a uniform $CoSi_2$ layer with the $CoSi_2$ grains, which are in the form of epitaxial-like growth on the each poly-Si grains, causing a reduction of the interfacial energy of the system.

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Distribution Characteristics of Organic Matters and Heavy Metals in Surface Sediments of Samcheok Port (삼척항 표층퇴적물 내 유기물 및 중금속 분포 특성)

  • Shin, Woo-Seok;Kim, Young-Kee
    • Applied Chemistry for Engineering
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    • v.31 no.5
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    • pp.481-486
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    • 2020
  • To evaluate geochemical characteristics of surface sediments in Samcheok Port, the distribution characteristics of particle sizes, organic matters and heavy metals were investigated. The sediments showed a mixed property of sand, silt, and clay, however fine-grains dominated at the inner port and coarse-grains dominated at the outer port. The organic (COD, TOC, and IL) contamination of the sediment at the inner port were higher than that of the outer port, and the concentrations of total nitrogen and total phosphorus at the inner port was higher than those of the outer port. Also, heavy metals contamination of surface sediments at the inner port was higher than those of the outer port (except for As). From the results of high organic matter concentrations and C/N ratio at the inner port, it is considered that the contamination of organic matters was mainly derived from the land. The correlation analysis among the particle size, chemical composition, and heavy metals resulted in high correlation between silt-clay and heavy metals, and between organic matters and heavy metals. The sequential extraction results of heavy metals showed the sum of exchangeable, carbonate, and oxide fractions of Ni, Zn, Cu, Pb, Cd, and As were 14.8, 49.8, 39.1, 32.2, 51.8 and 26.6%, respectively.

CoFe2O4 Films Grown on (100) MgO Substrates by a rf Magnetron Sputtering Method ((100) MgO 기판에 성장한 CoFe2O4 박막의 물리적 및 자기적 특성에 관한 연구)

  • Lee, Jae-Gwang;Chae, Kwang-Pyo;Lee, Young-Bae
    • Journal of the Korean Magnetics Society
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    • v.16 no.2
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    • pp.140-143
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    • 2006
  • Single crystalline $CoFe_2O_4$ thin films on (100) MgO substrates were fabricated using a rf magnetron sputtering method. The deposited films were investigated for their crystallization by X-ray diffraction, Rutherford back-scattering spectroscopy and field emission scanning electron microscopy. When a cobalt ferrite film was deposited at the substrate temperature of $600^{\circ}C$, squared grains of about 200 nm were uniformly distributed in the film. However, the grains became irregular and their sizes also varied from 30 to 150 nm when the substrate temperature was $700^{\circ}C$. Hysteresis loops of a film deposited at $600^{\circ}C$ showed that the magnetically easy axis of the film was perpendicular to the substrate surface. Except for the squareness ratio, magnetic properties of the cobalt ferrite films grown by the present rf sputtering method were as good as those of the films prepared by a laser ablation method: The in-plane and perpendicular coercivities were 283 and 6800 Oe, respectively. As the thickness of the deposited film increased twice, the saturation magnetization became double but the coercivity remained unchanged. However, deposition of the Co ferrite films with a higher rf powder decreased the squareness ratio and the perpendicular coercivity of the films.

Sintering and Dielectric Characteristics of LaAlO3 Ceramics by Mechanochemical Treatment from La2O3-A12O3 and La2O3-Al(OH)3 (La2O3-Al2O3와 La2O3-Al(OH)3를 메카노케미칼로 처리한 LaAlO3세라믹스의 소결 및 유전특성)

  • 최상수;조정호;김강언;정수태;조상희
    • Journal of the Korean Ceramic Society
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    • v.39 no.1
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    • pp.68-73
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    • 2002
  • The dielectric properties and synthesis of $LaAlO_3$ ceramics from mixtures of $La_2O_3-Al_2O_3$ (LAO) and $La_2O_3-Al(OH)_3$(LAH) via grinding process were investigated. The single phase $LaA1O_3$of LAO and LAH powders were formed at $1300^{\circ}C$ and $1000^{\circ}C$, respectively. A non-reacted $La_2O_3$ existing in calcined powder was changed to La(OH)$_3$by moisture in the air, and their samples were worse than those of the samples made from a $LaA1O_3$single phase powder. The densities of LAO samples sintered at 150$0^{\circ}C$ for 4 h and LAH samples sintered at $1400^{\circ}C$ for 4 h were 97.3% and 98.3% of theory density, respectively. Grains of LAH sample showed uniformity and their sizes were 0.75 ${\mu}{\textrm}{m}$, and LAO samples showed non-uniformity and their sizes were 4-5 ${\mu}{\textrm}{m}$. Dielectric constant of LAO and LAH samples were the same value (≒22), however dielectric loss of LAH sample (0.0003) were lower than that of LAO sample(0.001)due to grain size.

A Study on a Morphological Identification of Pinelliae Tuber, Typhonii Flagelliformis Rhizoma and Arisaematis Rhizoma (반하(半夏), 수반하(水半夏) 및 천남성(天南星)의 형태(形態) 감별에 관한 연구)

  • Choi, Young-Seong;Kil, Ki-Jung;Lee, Young-Jong
    • The Korea Journal of Herbology
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    • v.22 no.2
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    • pp.103-108
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    • 2007
  • Objectives : A morphological classification among Pinelliae Tuber, Typhonii Flagelliformis Rhizoma and Arisaematis Rhizoma was made through microscopic observation. Method : The slice of the tested material made by paraffin section technique was colored with Safranine Malachite Green contrast methods, and then observed and photographed by olymphus-BHT. Result : 1. Pinelliae Tuber is like a ball with a $1{\sim}1.5cm$ diameter, with a concave apex and pockmarked root trace around. 2. Typhonii Flagelliformis Rhizoma is somewhat oval or like a cone, with a $4{\sim}8mm$ diameter, a $7{\sim}15mm$ height, a projected round apex, and a pin-pointed back. 3. Arisaematis Rhizoma is somewhat flat round with a $2{\sim}2.5cm$ diameter, a little than Pinelliae Tuber, and its apex has incomplete lobopodium and root trace. 4. Fundamental tissues of Pinelliae Tuber, Typhonii Flagelliformis Rhizoma, and Arisaematis Rhizoma have starch grains and mucilage cells, and their mucilage cells include the raphides of calcium oxalate. Conclusion : Internal forms of Pinelliae Tuber, Typhonii Flagelliformis Rhizoma, and Arisaematis Rhizoma are difficult to distinguish from one another, but Pinelliae Tuber and Arisaematis Rhizoma can be distinguished by their external forms and sizes, and Pinelliae Tuber and Typhonii Flagelliformis Rhizoma were distinguished by the forms of apex.

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Effect of PZN addition on microstructure of PZT thick films by aerosol deposition process (에어로졸 증착법에 의한 PZT 후막의 미세구조에 미치는 PZN 첨가의 영향)

  • Jang, Joo-Hee;Park, Yoon-Soo;Park, Dong-Soo;Park, Chan
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.28 no.1
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    • pp.14-20
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    • 2018
  • Lead zinc niobate (PZN) added lead zirconate titanate (PZT) thick films with thickness of $5{\sim}10{\mu}m$ were fabricated on silicon and sapphire substrates using aerosol deposition method. The contents of PZN were varied from 0 %, 20 % and 40 %. The initial particles (PZT, 2PZN-8PZT, 4PZN-6PZT) had irregular shape and submicron sizes. The as-deposited film had fairly dense microstructure without any crack, and showed only a perovskite single phase formed with nano-sized grains. The as-deposited films on silicon were annealed at the temperatures of $700^{\circ}C$, and the films deposited on sapphire were annealed at $900^{\circ}C$ in the electrical furnace. The effects of PZN addition on the microstructural evolution were observed using by FE-SEM and HR-TEM.

Evaluation of translucency of monolithic zirconia and framework zirconia materials

  • Tuncel, Ilkin;Turp, Isil;Usumez, Aslihan
    • The Journal of Advanced Prosthodontics
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    • v.8 no.3
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    • pp.181-186
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    • 2016
  • PURPOSE. The opacity of zirconia is an esthetic disadvantage that hinders achieving natural and shade-matched restorations. The aim of this study was to evaluate the translucency of non-colored and colored framework zirconia and monolithic zirconia. MATERIALS AND METHODS. The three groups tested were: non-colored framework zirconia, colored framework zirconia with the A3 shade according to Vita Classic Scale, and monolithic zirconia (n=5). The specimens were fabricated in the dimensions of $15{\times}12{\times}0.5mm$. A spectrophotometer was used to measure the contrast ratio, which is indicative of translucency. Three measurements were made to obtain the contrast ratios of the materials over a white background ($L^*w$) and a black background ($L^*b$). The data were analyzed using the one-way analysis of variance and Tukey HSD tests. One specimen from each group was chosen for scanning electron microscope analysis. The determined areas of the SEM images were divided by the number of grains in order to calculate the mean grain size. RESULTS. Statistically significant differences were observed among all groups (P<.05). Non-colored zirconia had the highest translucency with a contrast ratio of 0.75, while monolithic zirconia had the lowest translucency with a contrast ratio of 0.8. The mean grain sizes of the non-colored, colored, and monolithic zirconia were 233, 256, and 361 nm, respectively. CONCLUSION. The translucency of the zirconia was affected by the coloring procedure and the grain size. Although monolithic zirconia may not be the best esthetic material for the anterior region, it may serve as an alternative in the posterior region for the bilayered zirconia restorations.

Cooking and Milling Characteristics of Several Barley Starch Isogenic Lines (보리의 전분 Isogenic line들의 취반 및 제분 특성)

  • 송현숙;이홍석;정태영
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.39 no.1
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    • pp.63-72
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    • 1994
  • The relationships among the endosperm structure, physicochemical characteristics and cooking and milling properties were examined in this study by using the isogenic lines which have the same genetic background except starch characteristics. The isogenic lines were bread by combining three pairs of genes, of waxy or non-waxy, fractured or round starch granule, and shrunken or plump endosperm. Although grains weight and chemical compositions of the endosperms did not differ widely, but cooking qualities, amylose contents, $\beta$-glucan viscosities were significant differences between isogenic types. Water absorptions and expansibilities were highest in waxy lines, and lowest in fratured starch granular lines; the smaller the seed sizes were, the higher the water absorptions were. Mixogram pattern of cooked barley varied with the starch properties and milling properties were excellent in fractured granular lines, whereas those properties of the waxy and shrunken endosperm lines were not good.

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Optical and Electrical Properties of Fluorine-Doped Tin Oxide Prepared by Chemical Vapor Deposition at Low Temperature (저온 증착된 불소도핑 주석 산화 박막의 광학적·전기적 특성)

  • Park, Ji Hun;Jeon, Bup Ju
    • Korean Journal of Materials Research
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    • v.23 no.9
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    • pp.517-524
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    • 2013
  • The electrical and optical properties of fluorine-doped tin oxide films grown on polyethylene terephthalate film with a hardness of 3 using electron cyclotron resonance plasma with linear microwave of 2.45 GHz of high ionization energy were investigated. Fluorine-doped tin oxide films with a magnetic field of 875 Gauss and the highest resistance uniformity were obtained. In particular, the magnetic field could be controlled by varying the distribution in electron cyclotron deposition positions. The films were deposited at various gas flow rates of hydrogen and carrier gas of an organometallic source. The surface morphology, electrical resistivity, transmittance, and color in the visible range of the deposited film were examined using SEM, a four-point probe instrument, and a spectrophotometer. The electromagnetic field for electron cyclotron resonance condition was uniformly formed in at a position 16 cm from the center along the Z-axis. The plasma spatial distribution of magnetic current on the roll substrate surface in the film was considerably affected by the electron cyclotron systems. The relative resistance uniformity of electrical properties was obtained in film prepared with a magnetic field in the current range of 180~200A. SEM images showing the surface morphologies of a film deposited on PET with a width of 50 cm revealed that the grains were uniformly distributed with sizes in the range of 2~7 nm. In our experimental range, the electrical resistivity of film was able to observe from $1.0{\times}10^{-2}$ to $1.0{\times}10^{-1}{\Omega}cm$ where optical transmittance at 550 nm was 87~89 %. These properties were depended on the flow rate of the gas, hydrogen and carrier gas of the organometallic source, respectively.