• Applied Biological Chemistry
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• v.26 no.1
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• pp.47-52
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• 1983

The size distribution and changes of volume and grain hardness of ‘Sedohadaka', waked barley of various polishing yields during hydration process at various temperatures were investigated, and were analyzed kinetically, Both major and minor diameter of barley grain decreased linearly during polishing, and the decreasing rate of major diameter was greater than that of minor diameter. The volume change of barley grain could be expressed as a power of hydration time, and a break point was found in case of non-polished barley. The changing rate of grain hardness followed the equation of a first-order reaction, and the reaction rate constant increased with decreasing polishing yields and at higher temperature in the range of $20{\sim}60^{\circ}C$. The activation energy of hardness change reaction of polished barley during hydration were ranged $5.1{\sim}7.8Kcal/mole$, and 13.3Kcal/mole of non-polished barley.

• Journal of the Korean Wood Science and Technology
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• v.26 no.1
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• pp.63-69
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• 1998

This study was carried out to get some basic information on mechanical properties of Korea Lepidobalanus for rational utilization of wood. Five species of Quercus variabilis, Q. aliena, Q. serrata, Q. mongolica, Q. acutissima belong to Lepidobalanus were investigated in this research. Relationship of anatomical characteristics to compression strength parallel to grain was analyzed using stepwise regression technique. All possible combination of 21 independent variables were regressed on compression strength parallel to grain. The summarized results in this study were as follows: I. In the proportion of wood structural elements, the factors that had the greatest influence on compression strength parallel to grain appeared to be proportion of ray in earlywood in Q. variabilis and Q. acutissima, proportion of wood fiber in latewood in Q. aliena and Q. serrata and proportion of vessel in earlywood in Q. mongolica respectively. 2. In the size of wood element and its structure, the factors that had the greatest influence on compression strength parallel to grain were microfibril angle in Q. variabilis, Q. serrata and Q. mongolica and length of wood fiber in Q. aliena and Q. acutissima.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.21 no.1
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• pp.1-8
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• 2023

The major concern in the deep geological disposal of spent nuclear fuels include sulfide-induced corrosion and stress corrosion cracking of copper canisters. Sulfur diffusion into copper canisters may induce copper embrittlement by causing Cu₂S particle formation along grain boundaries; these sulfide particles can act as crack initiation sites and eventually cause embrittlement. To prevent the formation of Cu₂S along grain boundaries and sulfur-induced copper embrittlement, copper alloys are designed in this study. Alloying elements that can act as chemical anchors to suppress sulfur diffusion and the formation of Cu₂S along grain boundaries are investigated based on the understanding of the microscopic mechanism of sulfur diffusion and Cu₂S precipitation along grain boundaries. Copper alloy ingots are experimentally manufactured to validate the alloying elements. Microstructural analysis using scanning electron microscopy with energy dispersive spectroscopy demonstrates that Cu₂S particles are not formed at grain boundaries but randomly distributed within grains in all the vacuum arc-melted Cu alloys (Cu-Si, Cu-Ag, and Cu-Zr). Further studies will be conducted to evaluate the mechanical and corrosion properties of the developed Cu alloys.

• Journal of Biosystems Engineering
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• v.7 no.1
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• pp.1-16
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• 1982

The thermal conductivies of grain are influenced by many physical factors such as' initial temperature, moisture content, composition, bulk density or porosity of grain. However, not only few researchers considered all these factors in determining thermal conductivities of grain but also many researchers considered only moisture content as a major effective factor on the thermal conductivity. This study was conducted to experimentally determine the thermal conductivities of rough rice (3 Japonica-type, 3 Indica-type) and barley(covered, naked) as a function of initial temperature, moisture content and porosity of grain, and to investigate the effect of those physical factors on the thermal conductivities of grain. The results of this study are summarized as follows; 1. The average time correction value for this experimental apparatus was 7 sec, which. was insignificant to the calculated thermal conductivity. The resulting conductivity for considering time correction value was only 4.9 percent higher than that calculated by the non-corrected equation. 2. The thermal conductivity was in the range of 0.1208~0.2058W/$m^{\circ}K$ for naked barley, 0.1138~0.1724W/$m^{\circ}K$ for covered barley, 0.0912~0.1864W/$m^{\circ}K$ for Japonica-type rice and 0.086~0.1774W/$m^{\circ}K$ for Indica-type rice. 3. The thermal conductivities of grain increased with initial temperature and moisture content of grain but decreased with porosity of grain. 4. The regression equations of the thermal conductivity of each grain were determined as a function of initial temperature, moisture content and porosity. The regression equations of the thermal conductivity of both Japonica-type and Indica-type rough rice were also determined.

• Journal of Biosystems Engineering
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• v.6 no.1
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• pp.73-82
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• 1981

The physical properties of grain are very important for the design of handling, sorting, processing, and storage system. On the physical properties of grain, volume, bulk density, true density, specific gravity, and porosity arc the major factors affecting the thermal properties of grain. This study was conducted to determine experimentally the above physical properties of rough rice (3 Japonica-type, 3 Indica-type) and barley (covered, naked) as a function of moisture content ranged from about 10% to 25% (w.b). The results of this study are summarized as follows; 1. The volume of grain kernel increased with moisture content for both rice and barley. The volume of those grain kernel was in the range of $2.2068{\times}10^{-8}{\sim}3.3960{\times}10^{-8}m^3$ at the moisture content of 14%. 2. The bulk density of rice increased linearly with moisture content for Japonica-type rough rice and quadratically for Indica-type rough rice, but the bulk density of barley decreased linearly with moisture content. The bulk density of the grain was in the range of 501.14~689.13kg/$m^3$ at the moisture content of 14%. 3. The true density of whole grain decreased linearly with moisture content, and was in the range of 1019.49~1139.75kg/$m^3$ at the moisture content of 14%. 4. The porosity of rice decreased linearly with moisture content for Japonica-type rough rice and quadratically for Indica-type rough rice, but the porosity of barley increased linearly with moisture content. The porosity of the grain was in the range of 39.51~50.83% at the moisture content of 14%. 5. The regression equations of the physical properties such as volume, bulk density, true density, and porosity of the grain were determined as a function of moisture content.

• Preventive Nutrition and Food Science
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• v.10 no.4
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• pp.349-352
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• 2005

The growth inhibitory effect of wheat grain, fermented wheat grain products, red pepper powder and kochujang was examined in AGS human gastric adenocarcinoma cells. The kochujang samples were prepared by mixing red pepper powder and each fermented wheat grain products, such as first fermented wheat grain (FFWG), second fermented wheat grain (SFWG) and final fermented wheat grain (FiFWG). The methanol extract of FiFWG showed the highest growth inhibitory effects. In order to investigate the effects of fermented wheat grain products at each stage of fermentation on anticancer activity, the kochujang prepared with red pepper powder and each of FFWG, SFWG and FiFWG were fermented until reaching pH 5.1. The kochujang adjusted to pH 5.1 by fermentation increased the growth inhibitory effect; however, the kochujang prepared with FiFWG showed the highest effect. Increased fermentation time increased the growth inhibitory effect of kochujang when prepared with FiFWG. These results suggested that the anticancer effect of the kochujang on the gastric cancer cells was affected by the fermentation periods of the wheat grains. The well-fermented end products of the wheat grains seem to be one of the major components that showed anticancer activity of kochujang.

• Safety and Health at Work
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• v.10 no.1
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• pp.47-53
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• 2019

Background: Despite growing concern over occupational exposure to particulate matter (PM) such as grain dust and diesel exhaust, information about the exposure level and health implications among workers in small-scale milling enterprises in developing countries like Nigeria has not been adequately documented. The purpose of this study was to assess the level of exposure to grain dust and diesel exhaust and effect on lung function among grain millers in food markets in Ibadan metropolis, Nigeria. Methods: The study adopted descriptive cross-sectional design with a comparative approach. Sixteen grain milling shops each were randomly selected from two major food markets in Ibadan metropolis for indoor $PM_{10}$ and $PM_{2.5}$ monitoring. Seventy-two respondents each were proportionately selected from grain millers and shop owners for forced expiratory volume in one second and peak expiratory flow rate tests. Results: The $PM_{2.5}$ concentrations for both market locations ranged between 1,269.3 and $651.7{\mu}g/m^3$, while $PM_{10}$ concentrations were between 1,048.2 and $818.1{\mu}g/m^3$. The recorded concentrations exceeded the World Health Organization guideline limit of $50{\mu}g/m^3$ and $25{\mu}g/m^3$ for $PM_{2.5}$ and $PM_{10}$, respectively. As compared with control group (2.1 L), significantly lower forced expiratory volume in one second value (1.61 L) was observed among the exposed group (p < 0.05). Likewise, significantly lower peak expiratory flow rate value (186.7 L/min) was recorded among the exposed group than the control group (269.51 L/min) (p < 0.05). Conclusion: Exposure to grain dust and diesel exhaust accentuated respiratory disorders with declines in lung functions amongst grain millers. Improved milling practices and engaging cleaner milling facilities should be adopted to minimize exposure and related hazards.

• Journal of the Korean Wood Science and Technology
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• v.21 no.3
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• pp.45-52
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• 1993

Surveyed results on the slope of grain and the twist of sawn lumber of Pinus koraiensis, Larix leptolepis, and Pinus densiflora were summarized as follows: 1. The slope of grain of Pinus koraiensis has a Z-grain in the stem axis. The slope of grain was found to be the lowest at near to the pith and then constantly increased. At the height of 0.2m from the base of stem. a cross section of 35 annual rings was found to have a repeatedly increasing and decreasing slope of grain and then constantly decreased. At the height of 1.2m to 7.2m from the base of stem, the slope of grain increased conspicuously until the 10th annual ring, after which it increased near to the bark with repeatedly increasing and decreasing trends. 2. Pinus densiflora has a S-grain in the stem axis. The lowest slope of grain was found at near to the pith, and the highest in the 10 to 35 annual rings from the pith. 3. Larix leptolepis has a S-grain. At the height of 3.2m from the base of stem, the big fluctuation of the slope of grain was found without any particular trend. 4. The slope of grain and the twist between natural and reforested timber of Pinus koraiensis were found to be almost the same trend in viewpoint of the annual ring. The maximum slope of grain of imported Siberian timber of Pinus koraiensis was found at the 10 annual rings, which was quite similar to that of native species in Korea, but the big difference of the twist was found at 140 annual rings. 5. The twist was little at the mature wood of reforested Pinus koraiensis and Siberians and the duplicated part of mature and juvenile woods of those. On the contrary, the twist was great at the duplicated part of mature and juvenile woods of Pinus koraiensis. 6. The twist of Larix leptolepis showed the S-direction which coincided with that of slope of grain. The twist was greatest at the part of juvenile wood and little at the duplicated part of mature and juvenile woods, and little difference of twist was found between mature and juvenile woods. 7. Siberian larix having a minimum slope of grain showed the lowest twist, and the twist at the duplicated part of mature and juvenile woods showed a middle level of both mature and juvenile woods' portions.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2003.10a
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• pp.163-166
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• 2003

In this study, a grouping of particle-size distributions(PSDs) by means of the fuzzy c-means clustering method(FCM) was presented. The classification was performed with the whole and the major soil series representing pedological origin. In case of the major soil series, PSDs were clustered as $2{\sim}4$ groups and the characteristics of clustering results were quite different between the soil series. It was found that the characteristics of PSDs at center of each class can be explained by formation process of each soil series. In case of whole soil data, PSDs were classified to 8 classes in which 4 classes were single mode and 4 classes were bimode distributions. Through this study, it is concluded that pedogenetic process is a plausible explanation for grain size distribution of soils.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.10a
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• pp.155-159
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• 2002

This paper has studied to obtain the grinding characteristics and optimal grinding conditions of ceramics in the grinding with diamond wheel by Taguchi method. Feed rate was most important factor to the surface roughness. In the case of 4{Si_3}{N_4}$ and ${A1_2}{O_3}$, surface roughness value were small at 3m/min of feed rate. In the case of $ZrO_2$. surface roughness value was small at 4m/min of feed rate. Surface roughness have much influenced by major load for the :ii3N4 and $ZrO_2$. On the other hand, ${A1_2}{O_3}$ have more influenced by grain shedding of brittle fracture phenomenon. The major factors affecting the surface roughness and the optimum grinding conditions were obtained with minimum experiment using Taguchi method.