• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.8
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• pp.5468-5475
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• 2015

This present work was aimed to analyse characteristics of fermentation and aging of Korean traditional cheongju prepared by adding of different brewing water. The three different mashes were used for fermentation and maturation. The cheongju(A) was prepared without adding of brewing water in two stage mashing. Cheongju(B) and cheongju(C) were made with adding of 1 liter and 2 liter brewing water in two stage mashing respectively whereas the cheongju(B) and cheongju(C) showed higher fermentation ability than that of cheongju(A) regarding to pH, ethanol, specific gravity and sugar concentration(brix). In terms of volatile compounds content after six months aging, cheongju(A and B) prepared by adding brewing water showed the higher content of ethyl acetate than that of cheong(C) and the concentrations were maintained during the aging period. In addition, the content of fusel oil(n-propanol, i-butanol, n-butanol, i-bmyl alcohol, n-bmyl alcohol)indicated similar pattern as ethyl acetate. The organic acid of cheongju B(4873.46 mg/l) and C(4963.12 mg/l) also indicated the higher content than that of cheongju A(4661.47 mg/l). In conclusion, cheongju B and C prepared by adding brewing water in two stage mashing showed better quality and taste than that of cheongju A.

• Microbiology and Biotechnology Letters
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• v.32 no.3
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• pp.212-217
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• 2004

The gene coding for mannanase from Bacillus subtilis WL-7, a number of glycosyl hydrolase family 26, was hyperexpressed in Escherichia coli. Two recombinant plasmids, pE7MAN and pENS7, were constructed by introducing the complete mannanase gene and the mature mannanase gene lacking N-terminal signal peptide region into a expression vector pET24a(＋), respectively. The level of mannanase produced by E. coli BL21 (DE3) carrying pENS7, which included the mature mannanase gene, was considerably higher than that by E. coli BL21 (DE3)/pE7MAN. Almost mannanase produced by the recombinant E. coli carrying pENS7 at growth temperature of $37^{\circ}C$ existed as inactive enzyme of insoluble form. Growth at temperature below $31^{\circ}C$ increased the soluble fraction of mannanase having catalytic activity in the recombinant E. coli cells. The highest productivity of active mannanase was observed in cell-free extract of the recombinant E. coli grown at growth temperature ranging from $25^{\circ}C$ to $28^{\circ}C$, while mannanase activity per soluble protein of the cell-free extract was highest in the cells grown at $^31{\circ}C$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.4
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• pp.668-678
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• 2004

The purpose of this study was to estimate seasonal variation of nutritional intake and quality in adults in longevity areas. Dietary survey was given to 469 subjects over age 20 living Bukjeju-gun, Yecheon-gun, and Sunchang-gun of Korea, using 24-hour recall method every 4 seasons over one-year period. The mean daily intakes (%RDA) of 4 seasons were 1313.3 ㎉ (72.0%) for energy, 47.3 g (82.2%) for protein, 20.2 g for fat, 228.0 g for carbohydrate, 12.8 g for dietary fiber. The differences were hardly significant among the seasons. Mean daily intakes of most of the vitamins and minerals were lower than RDA except vitamin C and folate, especially %RDAs of Ca, vitamin D, vitamin B$_2$, vitamin E were less than 60% of RDA. In general, nutrient intake were high in spring compared to other seasons except vitamin C which was high in fall and winter. Mean daily intakes of cholesterol were 151.7 mg and 124.3 mg in males and females, respectively. The differences was significant between the two sexes but not among the seasons. PUFA : MUFA : SFA ratio of the subject was 1.0 : 1.3 : 1.2. Average CPF ratio of energy intake was 72.7 : 14.4 : 12.9, and energy intake ratio from carbohydrate was low in spring, in contrast energy intake ratios from protein was significantly high in spring. Mean adequacy ratio (MAR), an index of overall nutritional quality was 0.64 for female and 0.71 for male. The indices of nutritional quality (INQ) were over 1 for most of nutrients except 0.73 of Ca, 0.87 of vitamin A, 0.69 of vitamin B$_2$, and 0.65 of vitamin E. Both MAR and INQ were significantly different among sex and seasons, values were higher in males than in females and were higher in spring with the exception of vitamin C. In conclusion, subjects in longevity areas did not consume enough nutrients quantitatively as well as qualitatively, especially Ca, vitamin A, vitamin B$_2$, and vitamin E. Also mean daily intakes of most of vitamins and minerals were insufficient in females, and were significantly different among season. Therefore we must consider a counterplan to augment nutrition intake for them. In addition, it seems to be essential to micro nutrients to the food composition database to estimate dietary intakes more accurately.

• Journal of Korean Society of Forest Science
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• v.103 no.3
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• pp.439-445
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• 2014

In this study, we developed a dynamic stand yield model to estimate the baseline carbon stock, which is essentially required for a forest carbon offset project based on forest management. For developing the yield model, the data was acquired from the databases of the $5^{th}$ National Forest Inventory. The model was validated by comparing its estimations with field measurements that were conducted from 4 study sites (14 plots with thinning treatments) located in Hong-chun, Hoeng-sung, Yang-yang Daechi and Yang-yang Jungja. The difference between the estimations and the field measurements was less than 5%. Using the dynamic stand yield model, we estimated the changes in stand yield volume and carbon stocks for each species according to the baseline scenarios. As the results, we found that baseline carbon stock was the highest at Quercus acutissima stand (83.01tC/ha), while the lowest at Pinus rigida stand (32.17tC/ha) and Pinus densiflora stand of central region (39.09tC/ha). Hence, a project provider could get more carbon emission credits from an improved forest management project when considering the project with Pinus rigida stand or Pinus densiflora stand (central region). The baseline carbon stock and the dynamic stand yield model developed from this study would be useful for designing carbon offset projects based on improved forest management.

• Membrane Journal
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• v.16 no.2
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• pp.115-122
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• 2006

In this study the membrane preparation and water vapor permeation of the hydrophilic polymer materials, polyaminosiloxane and polyhydroxylsiloxane, used as the coating materials for the preparation of asymmetric flat and hollow fiber membranes were investigated. And the water vapor permeation towards air permeation and their permselectivity were intensively studied for the resulting Resin A/Resin C (coupling agent) and Resin B/Resin C membranes. The water vapor permeability for 3 wt% Resin C introduced into Resin A (Resin A/Resin C) membrane was higher than for 1 and 5 wt% membranes and also water vapor permeability increased with increasing operating temperatures. In addition, at this content of 3 wt% Resin C, the absorption capability became maximum through dynamic equilibrium absorption experiment. Water vapor permeability, 43578 Barrer (1 Barrer = $10^{-10}cm^3(STP){\cdot}cm/cm^2{\cdot}s{\cdot}cmHg$) and 53000 Barrer, and the selectivity of $P(H_2O)P(Air)$, 101.3 and 102.6 were shown at 25 and $35^{\circ}C$, respectively.

• Korean journal of food and cookery science
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• v.7 no.4
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• pp.15-22
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• 1991

Changes in cooking properties of kidney beans A (reddish purple), B (mosaic), and C (pale yellow) during storage at $4^{\circ}$, $20^{\circ}$ and $30^{\circ}C$ for 5 months were examined. The weight and volume gains of raw beans during soaking at $30^{\circ}C$ were the greatest in kidney bean A followed by B and C, which were decreased from 3 months storage at $30^{\circ}C$. The weight gain, solid loss and hardness of cooked beans at $100^{\circ}C$ for 40 min decreased from 3 months of storage at $30^{\circ}C$ in all samples. The amylograms of whole kidney bean flours showed no peak and continuous increase of viscosity during heating. The kidney bean A showed the higher values in all reference points than kidney beans B and C which had similar amylogram patterns.

• Journal of Plant Biology
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• v.24 no.1
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• pp.13-19
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• 1981

In order to investigate the effects of ammonium citrate and ammonium succinate on the growth and absorption of nitrogen compounds supplied in the medium, Korean ginseng (Panax ginseng C. A. Meyer) calli were suspension cultured in MS medium with various concentrations of ammonium citrate and ammonium succinate. When Korean ginseng calli were cultured with 10 mM ammonium citrate, 10 mM ammonium succinate, and 10 mM ammonium nitrate (control) in MS media as the nitrogen sources, the growth, $NO_3$-N absorption and total nitrogen content of the Korean ginseng cells were greatest in the ammonium citrate and ammonium succinate concentrations. When Korean ginseng calli were cultured with 5 mM ammonium citrate and 5 mM ammonium succinate, the growth and nitrogen content were superior to those of the control: however, $NO_3$-N and $NH_4$-N absorptions were similar to those of the control. In conclusion, the 10 mM ammonium citrate and 10 mM ammonium succinate may be better able to facilitate the growth and $NO_3$

• Journal of the Korean Ceramic Society
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• v.38 no.12
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• pp.1104-1109
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• 2001

Samples with the nominal composition, B $i_{1.84}$P $b_{0.34}$S $r_{1.91}$C $a_{2.03}$C $u_{3.06}$ $O_{10+}$$\delta$/ high $T_{c}$ superconductors containing As as an additive were fabricated by a solid-state reaction method. Samples with Ag of 10wt%, 30 wt% and 50 wt% each were sintered at 86$0^{\circ}C$~875$^{\circ}C$ for 24 hours. The structural characteristics, critical temperature and grain size with respect to Ag contents were analyzed by XRD(X-ray Diffraction) and SEM(Scanning Electron Microscope), respectively. As Ag contents increased, XRD peaks of g in Bi-2223 phase superconductors intensified and the proportion of the phase transition from Bi-2223 to Bi-2212 was increased.increased.

• Polymer(Korea)
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• v.35 no.1
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• pp.23-29
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• 2011

We measured shear viscosity of polymeric particles, prepared by suspension polymerization with hydrophobic silica as a stabilizer at $75^{\circ}C$, by a capillary rheometer. Shear viscosity displayed a non-Newtonian behavior with an increase in weight average molecular weight. Measurement of shear viscosity at 170 and $190^{\circ}C$ with copoly(styrene/butyl methacrylate) (co-PSB) particles by varying the ratio between styrene (St) and butyl methacrylate (BMA) showed that shear viscosity was a function of molecular weight, temperature and compositional ratio. When the ratio was 7/3, 5/5 and 3/7, shear viscosity slightly reduced with an increase in BMA concentration despite similar weight average molecular weights. We found that shear viscosity of copolymers with BMA concentrations exceeding 70% displayed a sharp reduction at high shear rates. It is speculated that increased PBMA chain length contributes to enhanced flowability of copolymers. When carbon black was incorporated into co-PSB, shear viscosity progressively increased with increasing carbon black concentration. The increase in shear viscosity, however, was less pronounced compared to the cases of molecular weight increase.

• Journal of the Korean GEO-environmental Society
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• v.17 no.3
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• pp.5-12
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• 2016

Stone column is the method that replace soft ground such as weak clay and loose sand with gravel or crushed stone which has relatively high stiffness and low compressive. Stone column increases bearing capacity of the soft ground, reduces settlement, produces ground improvement effect by consolidation drain, and is effective to prevent soil liquefaction in sandy ground during an earthquake. Stone column has been used in many civil works, and has recorded quite a lot of construction achievement internationally, but there is no standardized settlement calculation method yet. Therefore, in this study, the applicability of the existing theoretical equations were evaluated through comparison and analysis to predict a reasonable settlement of the Stone column. Consequently, Hook's law formula was verified to be the most close to numerical analysis.