• Composites Research
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• v.20 no.5
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• pp.43-48
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• 2007

The absorption and the interference shielding of electromagnetic wave have been very important issues for commercial and military purposes. The stealth technique is one of the most typical applications of electromagnetic wave absorption technology. This study has started for the development of composite fillers containing dielectric and magnetic lossy materials. To improve the electromagnetic characteristics of conductive nano fillers, carbon nanofibers (CNFs) with nickel-phosphorous (Ni-P) or nickel-iron (Ni-Fe) have been fabricated by the electroless plating process. Observations by the electron microscopy (SEM/TEM) and element analyzer (EDS/ELLS) showed the uniform Ni-P and Ni-Fe coated CNFs. The compositions of the plating layers were about Ni-6wt%P and Ni-70wt%Fe, respectively. The average thicknesses of the plating layers were about $50\;{\sim}\;100\;nm$.

• Journal of the East Asian Society of Dietary Life
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• v.24 no.1
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• pp.28-41
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• 2014

The distinctive physiological effect of dietary fiber in the body were studied according to contents and characteristics of each fiber component. In the present study, the composition of fiber in vegetables was investigated, and the effect of heat treatments on fiber content was studied. Contents of total pectin were 0.89~2.75 g/100 g on dry weight basis, with most contents from 1~2 g/100 g. The hot water soluble pectin (HWSP) content of vegetables ranged from 0.33~0.98 g/100 g, sodium hexametaphosphate soluble pectin (HXSP), from 0.29~0.81 g/100 g and HCl soluble pectin(HCLSP), from 0.30~1.40 g/100 g. HCLSP showed the greatest variation according to the type of vegetables. Every vegetable types showed similar contents of these three pectic fractions. Fiber contents of vegetables ranged from 8.8~23.8% for cellulose, 0.6~10.6% for hemicellulose, 1.0~5.2% for lignin, 10.9~25.4% for acid detergent fiber (ADF) and 11.8~31.9% for neutral detergent fiber (NDF) on dry weight basis. Especially, peppers showed higher contents of NDF than the other vegetables. It was found that a great portion of NDF, which is total insoluble dietary fiber, was composed of cellulose since cellulose constituted 63% of NDF. Heat treatment reduced total pectin content in all vegetables regardless of the heating methods and the greatest reduction was observed upon boiling. HWSP content increased, whereas HXSP and HCLSP contents decreased. Heat treatment increased the NDF, ADF and cellulose contents, and most changes were due to changes in cellulose content. The values of hemicellulose and lignin showed irregular pattern upon heating. Contents of total dietary fiber (TDF) were 1.20~7.11% on fresh weight basis. Garlic, edible burdock and pepper leaf showed higher contents of TDF than other vegetables. It was found that a great portion of TDF was composed of insoluble dietary fiber.

• Economic and Environmental Geology
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• v.49 no.1
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• pp.1-11
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• 2016

Chrysotile is well known as a fibrous mineral in serpentinite by the previous studies in S. Korea. Previous studies in other countries showed that antigorite also occurred as asbestiform and harmful to humans. Therefore, the objective of this study was to investigate types and characteristics of fibrous serpentine minerals occurred in serpentinite in Hongseong, Chungnam and Gapyeong, Gyeonggi in S. Korea. XRD, SEM-EDS, PLM and EPMA mapping analyses were used to examine the occurrence and formation mechanism of serpentine minerals. Serpentinization partially occurred in amphibole-schist and calc-schist at two study sites, Hongseong, Chungnam and Gapyeong, Gyeonggi, respectively. Both chrysotile and antigorite occurred as a fibrous mineral at Hongseong site, but chrysotile occurred as a fibrous mineral at Gapyeong site. Based on PLM analysis with dispersion staining, the chrysotile was observed horizontally magenta and vertically blue colors. The antigorite appeared as horizontally gold to golden magenta and vertically blue magenta colors under central stop dispersion staining objective(DSO). PLM and SEM analyses showed the fibrous minerals were formed from plate form of serpentine minerals or by hydrothermal alternation of primary minerals. The EPMA mapping showed that Mg contents in chrysotile is relatively higher than that in antigorite while Si and O contents in antigorite is higher than them in chrysotile. However, more studies are necessary to know the exact variation in chemical composition of chrysotile and antigorite. These results indicate that even though asbestiform antigorite found associated with asbestos chrysotile in serpentinites, the fibrous antigorite can be distinguished from chrysotile by different dispersion staining colors.

• Horticultural Science & Technology
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• v.33 no.3
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• pp.435-442
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• 2015

The main objective of this work was to identify and evaluate possible substrate alternatives or amendments to peat moss. This study involves the physical and chemical characterization and growth test of wood sawdust and wood fiber in order to evaluate their use as components of horticultural media. The carbohydrate content, C/N ratio, pH, phenolic compound, total porosity and water holding capacity were 58.9%, 425.1, 4.8, 181.8 ($mg{\cdot}g^{-1}$), 82.5% and 47.1% in wood sawdust and 41.1%, 240.8, 5.9, 29.8 ($mg{\cdot}g^{-1}$), 90.6% and 56.2% in wood fiber, respectively. Wood sawdust (K, $998.0mg{\cdot}100g^{-1}$ ; Ca, $1196.0mg{\cdot}100g^{-1}$; Mg, $105.6mg{\cdot}100g^{-1}$) and wood fiber (K, $1250.1mg{\cdot}100g^{-1}$; Ca, $1982.6mg{\cdot}100g^{-1}$; Mg, $173.1mg{\cdot}100g^{-1}$) showed adequate mineral elements properties compared to peat moss (K, $0.02mg{\cdot}100g^{-1}$; Ca, $0.57mg{\cdot}100g^{-1}$; Mg, $0.13mg{\cdot}100g^{-1}$) for their use as growing media. The mixtures of the horticultural media were prepared using different substrate as wood sawdust and wood fiber to grow Chinese cabbage (Brassica campestris L.) in a greenhouse. The seed germination, leaf area and stem height were 75%, $0.50cm^2$ and 2.8 cm in PS substrate (containing 30% peat moss, 10% perlite and 60% wood sawdust) and 95%, $0.65cm^2$ and 3.3 cm in PF substrate (containing 30% peat moss, 10% perlite and 60% wood fiber), respectively. The seed germination and stem height of the PF substrate (containing 30% peat moss, 10% perlite and 60% wood fiber) was higher than those in peat moss (control). Utilization of wood by-product can be considered as an alternative media component to substitute the widely using expensive peat moss.

• Proceedings of the Korean Society of Food and Cookery Science Conference
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• 2003.10a
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• pp.100-100
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• 2003

홍화꽃의 식품재료적 가치를 높이는 기초적 연구의 일환으로 한국산과 중국산의 화학적성분을 비교분석한 결과는 다음과 같다. 홍화꽃의 일반성분은 한국산 홍화꽃의 조단백질, 조지방, 조회분, 조섬유, 무질소물의 함량이 14.70%, 3.10%, 6.90%, 18.20%, 57.10%이었으며 중국산 홍화꽃은 12.60%, 2.70%, 5.80%, 16.40%, 62.50%로 나타나 무기질소물을 제외하고 한국산 홍화꽃이 중국산 홍화꽃보다 높게 나타났다. (중략)

• Journal of the Korean Applied Science and Technology
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• v.35 no.3
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• pp.702-708
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• 2018

Hydrogels are natural polymer networks that can contain huge quantities of water and many cosmetical ingredients. Their hydrophilic functional groups creates a matrix, which allows high efficacy in delivering active ingredients into the skin. In industry, hydrating properties and strength of the hydrogels are of great interest in manufacturing hydrogel mask packs. We have used the cellulose in various forms such as powder, cotton fiber and cellulase treated cotton fiber to investigate the property changes of cellulose/hydrogel sheets. When 0.1% and 0.3% of cellulose powder were added to hydrogels, tensile strength of hydrogel sheets were decreased by 10% and 14% respectively. Vise versa, when 0.5 ~ 2 cm of cotton fibers were added, tensile strength of hydrogel sheets were significantly increased by about 20%. The hydrogels which contain cotton fibers also gave an excellent moisturizing effect. Especially cellolose/hydrogels containing cellulase-treated cotton fibers showed the best effect on retaining moisture content increasing upto 380% in comparison with the one containing untreated cotton as well as excellent dispersibility.

• Applied Biological Chemistry
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• v.23 no.1
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• pp.45-51
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• 1980

Crude fiber, ash and crude fat in various parts of root had highly significant correlation each other. In shoot, crude fiber showed highly significant negative correlation with crude fat or crude protein which were in highly significant positive correlation each other. In whole plant, crude fiber and ash, crude fat and crude protein, Mn and Cu, ash and Ca, and ash and B showed positive correlation respectively and negative between crude protein and crude fiber. Ash, crude fat and curde fiber showed highly significant positive correlation with all mineral nutrients in root while in shoot pairs haying significant correlation were less and most of these were in negative correlation. Ash with Mg, K or Cu, crude fat with B, crude fiber with Cu, K, Mg in root and crude fat with Mn in shoot were specially high significant pairs. Ash with B and crude fat with Mn were significant in root, shoot and whole plant. Saponin contents in root showed highly significant positive correlation with crude fiber, crude fat, ash and with all other mineral nutrients except N, P, Mg while, in shoot, it showed, negative correlation with K and crude fiber, ana positive with N, Mn, Cu, and crude fat. Saponin showed positive correlation with crude fat, Mn, Cu, in root, shoot and whole plant.

• Journal of the Korea institute for structural maintenance and inspection
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• v.15 no.1
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• pp.159-168
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• 2011

In this study, we find out the feasibility of self-consolidating concrete with EP nylon fiber. Three kinds of method were used; when length of nylon fiber is differed for the experiment to investigate usability of nylon fiber with enhanced performance by dispersing-agent coating in self-consolidating concrete, when mixing in other organic fibers (polypropylene, cellulose) and in case of Binary Blended and Ternary Blended concrete mixed with different types of mineral admixtures (blast-furnace slag and fly ash). Based on the results of the experiment described above, comparison was made on the basic properties and dynamic characteristics of general fiber reinforced concrete mixed with enhanced performance nylon fiber and SCC mixed with enhanced performance nylon fiber as a Mock-up test prior to the experiment of application to the actual structure. Considering characteristics and durability of the fresh and hardened self-compacting concrete, dynamic characteristics and durability were found to be more outstanding when using nylon fiber for the mineral admixtures used, dynamic characteristics and durability were found to be more outstanding when using blast-furnace slag.

• Journal of the Korea institute for structural maintenance and inspection
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• v.26 no.3
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• pp.72-83
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• 2022

This paper studied the effect on the microstructure, electrical properties, and compressive strength of cement mortar containing carbon fiber (CF) and steel fiber (SF), which are conductive materials. The resistivity of conductive fiber-reinforced cement mortar (FRCM) was measured using the 4-probe method, and the compressive strength was measured based on the compression test. Their performance was compared and reviewed with plain mortar (PM). Furthermore, the surface shape and composition of the fracture surface of the conductive FRCM were analyzed using a scanning electron microscope (SEM) and an energy disperse X-ray spectrometer (EDS). The results showed that the resistivity gradually increased as the curing time increased in all specimens, whereas the resistivity decreased significantly as the fiber volume fraction increased. Adding steel fibers up to 1.25% did not affect the resistivity of cement mortar considerably. On the contrast, the resistivity of carbon fiber was somewhat decreased even at low contents (ie, 0.1 to 0.3%), and thereafter, it was significantly decreased. The percolation threshold of the conductive CFRCM containing CF used in this experiment was 0.4%, and it is judged to be the optimum carbon fiber dosage to maximize the conductive effect while maintaining the compressive strength performance as much as possible. For the surface shape and composition analysis of conductive FRCM, the fracture surface was observed through SEM-EDS. These results are considered to be very useful in establishing the microstructure mechanism of reinforcing fibers in cement mortars.

• Korean Journal of Food Science and Technology
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• v.26 no.3
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• pp.288-294
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• 1994

Dietary fiber contents in brans of the two representative Korean rice varieties, Chucheong and Sucheon were measured by the AOAC method, and the composition of total dietary fiber (TDF) was analyzed with the acid detergent fiber (ADF) procedure. Rice bran contained more than 25% of TDF, most of which was insoluble dietary fiber. Hemicellulose was shown to be the major constituent and rice bran dietary fiber contained distinctive amounts of cellulose and uronic acid. Consecutive acidalkaline treatment of rice bran considerably increased soluble dietary fiber (SDF) content and water-holding capacity (WHC). WHC of wheat flour-rice bran dietary fiber mixture increased with the proportion of rice bran dietary fiber. Analysis of the differential scanning calorimetry thermograms revealed that rice bran dietary fiber effectively retarded retrogradation of wheat starch.