• Journal of Korean Society of Forest Science
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• v.60 no.1
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• pp.51-57
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• 1983

Properties and glue shear strength of each water soluble rues-phenol copolymer adhesive and phenolic resin adhesive were examined as a high temperature curing binder through the manufacture of plywood made of Kapur veneer. The former has different molar ratio and the latter was made from different catalyst method. The results are summarized as follows: 1) Specific gravities of air dried plywood manufactured from each adhesive ranged from 0.67 to 0.82 and their moisture contents met the K.S. standard 2) In dry and wet shear strength, adhesives with 60 percent of non volatile content showed higher values than those with 50 percent except phenolic resin. Urea-phenol copolymer resin with 20 percent of phenol content exhibited the highest, and that with 70 percent the lowest. Filling effect of wood flour on the bonding strength is great in urea-phenol copolymer resin with more than 50 percent of phenol content, especially significant in 50 percent of non volatile content including alkali catalyst phenolic resin. Alkali and acid catalyst methods were the highest among the adhesive manufacture methods. In wet strength, urea resin belongs to the lowest group. 3) In glue shear strength after boiling and drying test, no method for manufacturing phenolic formaldehyde resin adhesive was stronger than alkali and acid catalyst methods. Phenolic resin made from alkali catalyst method needs a wood flour filler to improve the bonding quality. Urea-phenol copolymer resin with 10 percent of phenol content showed the reasonable water resistance.

• Journal of the Korean Home Economics Association
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• v.39 no.1
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• pp.91-102
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• 2001

The non-starch polysaccharides in the cell wall of rice, glutinous rice, and black rice, were analyzed. They were fractionated into fractions; water-soluble, hot writer-soluble, ammonium oxalate-soluble, sodium hydroxide-soluble, potassium hydroxide-soluble, and the alkali-insoluble, according to the solvent solubility. The dietary fiber contents were 5.4% in glutinous rice, 4.2% in rice and 7.5% in black rice. The sodium hydroxide soluble fibers were abundant in each kind of rice, especially 4.01% in black rice. The water soluble fibers were 80% of dietary fiber in glutinous rice, 66% in rice, 86% in black rice. It was supposed that the content of the water soluble fibers in rice was increased by pounding. Pectic substances in water soluble fibers, hot water soluble fibers, and ammonium oxalate soluble fibers fraction, were 2.4% in glutinous rice fraction,1.59% in rice, and 1.12% in black rice. Alkali soluble fibers were considered as hemicellulose. Black rice contained 5.80% of hemicellulose, which was more than twice as much as glutinous rice(2.58%) and rice(2.22%). Alkali insoluble fibers were considered as cellulose, which showed no considerable difference. Among samples content of uronic acid in glutinous rice, rice and black rice were 0.9%, 0.66%, 1.8% respectively. Uronic acid of black rice was twice more than other samples tested. The fraction of black rice that uronic acid was extracted at most was the fraction of sodium hydroxide. Mono saccharides of the fraction was the glucose, the arabinose, the xylose.

• Journal of the Mineralogical Society of Korea
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• v.21 no.3
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• pp.239-246
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• 2008

Yeongweol sericite deposit of Gangwon Province is regarded as one of the sericite deposits derived from granitic rocks due to post-magmatic alkali metasomatism, and the other sericite deposit of the same origin is the Daehyun mine of Gyungbug Province. Sericite ores were originated from leucocratic granitic stocks of Cambrian-Triassic age which intruded the pegmatitic migmatite of the unknown age and granite of the Pre-cambrian age, respectivcly. Jangsan quartzite of the lowermost formations of the Paleozoic era, which played as the capping rock protected from the leakage of the hydrothermal solution. It is well known that those sericite deposits arc formed during formation of the geosyncline, and they are also situated in the margins of the Hambaeg Syncline. Leucocratic granites commonly contain pegmatites with tourmaline crystals, and are rich in potassium feldspars, and sodium plagioclase as well. Sericitized ores are mainly found as we go up to the higher elevations or to the margins of the stocks. And some of the Highest grade sericite ores show the monominerallic character composed of nearly pure sericite probably doc to the ultra greisenization. Chemical analysis shows higher $Na_{2}O$ and $K_{2}O$ contents $(2.00\sim7.03wt%)$ as the sericitizations arc preceded and they represent obvious greisenization. But low CaO contents $(0.05\sim4.51wt%)$ indicate that albitizations are so weak. Pyrophyllite of the Youngweol area is often accompanied by the sericite, indicating rather stronger thermal effect than the Daehyun mine. It is known that there are several Sn deposits originated from greisenization in the Taebaegsan region. And greisens are inclined to contain W, Mo and several REE's such as Be, Nb and Li, and so Taebaegsan region interbedded with lots of carbonate formations are still worthwhile to survey for those metallic deposits.

• Journal of the Korea Concrete Institute
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• v.28 no.5
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• pp.593-600
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• 2016

The paper presented investigates the effects of kaolinite on strength properties of alkali-activated multi-component cement. The binders of this study was blended of ground granulated blast furnace slag (GGBFS), fly ash (FA), silica fume (SF) and kaolinite (KA). In this study, the specimens of combination of 20%~70% GGBFS, 10%~60% FA, 10% SF (constant ratio) and 10%~50% KA binder were used for strength properties tests. The water/binder ratio was 0.5. The binders (GGBFS + FA + SF + KA) was activated by sodium hydroxide (NaOH) and sodium silicate ($Na_2SiO_3$) was 10% by total binder weight (10% NaOH + 10% $Na_2SiO_3$). The research carried out is on the compressive strength, water absorption, ultrasonic pulse velocity (UPV) and X-ray diffraction (XRD). The compressive strength decreased as the contents of KA increase. One of the major reason for this is the low reactivity of KA compared with other raw materials used as precursors such as GGBFS or FA. The presence of remaining KA indicates that the initially used quantity has not fully reacted during hydration. Moreover, the results have indicated that increased of KA contents decreased UPV under all experimental conditions. The drying shrinkage and water absorption increased as the content of KA increase. Test result clearly showed that the strength development of multi-component blended cement were significantly dependent on the content of KA and GGBFS.

• Journal of the Korean Wood Science and Technology
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• v.28 no.3
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• pp.34-41
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• 2000

Recently many scientists have tried to synthesize biodegradable polymers due to durable and non-biodegradable products of conventional synthetic plastics when these were wasted in nature. So to reuse the wastepapers for biodegradable polymer resources, ONP (old newsprint), OCC (old corrugated containerbpard) were carried out by the pretreatment of chlorinite, hypochlorite and oxygen-alkali treatment conditions. For manufacturing of biodegradable polymer with wastepaper, this study performed to investigate change of chemical components and optimal pretreatment condition. The summarized results in this study were as follows: Lignin content in ONP and OCC was was higher than in MOW and ash content was the highest in MOW. More amount of ash components were reduced by wet defiberation than by dry defiberation. Wet defiberation fiber are better than dry defiberated fiber in chemical pretreatment condition for wastepapers, and the best result was obtained in the condition of sodium chlorite at $70^{\circ}C$, because it has high delignification ratio, ${\alpha}$-cellulose contents and degree of polymerization in this treatment condition. Oxygen-alkali treatment condition is the worst method because of low yield, low degree of polymerization in this pretreatments.

• The Journal of Engineering Geology
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• v.15 no.4 s.42
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• pp.391-405
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• 2005

Chemical and isotopic analysis for stream water, shallow groundwater, intermediate groundwater and deep groundwater was carried out to grasp hydrogeochemical characteristics of groundwater in the Heunghae area, Pohang city. Water type of stream water and shallow groundwaters is typified as Ca-Cl type, intermediate groundwater is $Na-HCO_3$, and deep groundwater is prominent in Wa-Cl type. $HCO_3^-\;and\;SiO_2$ in shallow groundwater are originated from weathering of silicate minerals, whereas those of deep groundwaters are resulted from weathering of carbonate minerals. Ca and Mg ions in both shallow and deep groundwaters are resulted from weathering of calcite and dolomite. $SO_4^{2-}$ in shallow groundwater is originated mainly from pyrite oxidation. As well depth increases, pH and TDS increase, but Eh and DO decrease. Alkali metal contents(K, Na, Li) increases as well depth increases, but alkali earth metal(Mg, Ca) and hi concentrations increase as well depth decreases. Anions, halogen elements(F, Cl, Br), and $HCO_3$ contents increase as well depth increases. The average stable isotope value of the groundwater of each depth is as follows; deep groundwater: ${\delta}^{18}O=-10.1\%o,\;{\delta}D=-65.8\%_{\circ}$, intermediate groundwater: ${\delta}^{18}O=-8.9\%_{\circ},\;{\delta}D=-59.6\%_{\circ}$, shallow groungwater : ${\delta}^{18}O=-8.0\%_{\circ},\;{\delta}D=-53.6\%_{\circ}$, surface water : ${\delta}^{18}O=-7.9\%_{\circ},\;{\delta}D=-53.3\%_{\circ}$ respectively.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.52 no.4
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• pp.375-379
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• 2007

This study was carried out to examine the effects of storage duration on physico-chemical properties of milled rice. Rough rice of three rice ecotypes(Japonica, Tongil and F1 hybrids with Tongil back-ground) was stored for 4, 16, 28 and 40 months without artificial environmental control in seed warehouse. And this materials were investigated for seed germination rate, brown rice hardness, alkali digestion value(ADV), contents of protein, amylose, total sugar, and reducing sugar. Seed germination rate was significantly reduced with storage duration increased regardless of rice ecotypes : 66.7% from 16 months storage, 2.5% from 28, and nil from 40 months storage in Japonica rices. And 54.0%, 67.9% in Tongil, and F1 hybrid after 40 months storage, respectively. Brown rice hardness was not significantly affected by storage duration but showed significant genotypic differences. As the storage duration prolonged, sugar content and alkali digestion value increased, protein content declined while amylose content did not show clear tendency. Total and reducing sugar contents showed sharp increase upto 16 months storage and thereafter steady in crease, and the percentage of reducing sugar content out of total sugar content increased with extended storage duration.

• Applied Biological Chemistry
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• v.38 no.5
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• pp.425-430
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• 1995

The effects of oxidation stability and flavor acceptability of soybean oil by roasting and refining treatment were investigated in this study. The peroxide values of crude oil from unroasted soybean(COUS) were more increased than those of crude oil from unroasted soybean(CORS) during storage under fluorescence light at $45^{\circ}C$. Induction time by the Rancimat Method was 44.9 and above 88.7 hours on COUS and CORS respectively. The order of oxidation stability of oil was crude>degummed>alkali-refining>deodorized>bleached oil in terms of peroxide value, while that of oxidation stability of oil was crude>degummed>deodorized>alkali-refining>bleached oil in regard to induction time by the Rancimat Method. The correlation coefficients between induction time and two charateristics(absorbance of browning reaction products and phosphorous contents) were highly significant, while that between induction time and tocopherol contents was not high during refining stages. The scores for the sensory evaluation of flavor on sesame oil and CORS was 9.269 and 8.269 respectively, but it was not significant between two oils.

• Korean Journal of Food Science and Technology
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• v.44 no.5
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• pp.577-582
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• 2012

The purpose of this study was to investigate the preparation and physicochemical characteristics of n-octenylsuccinylated (OSAn) rice starches with different rice amylose contents. Amylose contents of Jinsumi flour and Milyang 261 flour were 15.42 and 20.31%, respectively. After processing by alkali treatment, amylose contents of Jinsumi rice starch and Milyang 261 rice starch were 34.21% and 39.32%, respectively. After OSAn treatment, the degree of substitution and reaction efficiency of Jinsumi starch were higher than those of Milyang 261. The stability of the modified Jinsumi emulsion was higher than that of the Milyang 261 emulsion. Viscosity of the Jinsumi emulsion was higher than that of the Milyang 261 emulsion. When the emulsions were spray dried, modified Jinsumi rice starch showed excellent coating efficiency compared to that of modified Milyang 261 rice starch. Therefore, Jinsumi was more suitable than Milyang 261 to apply for encapsulation as wall materials.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.4
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• pp.518-523
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• 2016

This study investigated the nutritional components and antioxidant activity of dry bitter melon (Momordica charantia L.). The moisture, crude protein, crude fat, crude ash, carbohydrate, and ascorbic acid contents of dry bitter melon were 6.10%, 3.31%, 1.08%, 2.31%, 87.20%, and 908.84 mg/100 g, respectively. Potassium was the most abundant mineral, followed by Mg, P, Na, Ca, Zn, Cu, and Mn, which means dry bitter melon was an alkali material. Regarding amino acid contents, dry bitter melon was rich in arginine, urea, asparagine, ${\gamma}-aminobutyric$ acid, and alanine. Total polyphenol and total flavonoid contents of dry bitter melon extract were 36.08 mg gallic acid equivalents/extract g and 15.66 mg tannic acid equivalents/extract g, respectively. The $IC_{50}$ value for 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity was 9.81 mg/mL for dry bitter melon ethanol extracts.