• Korean Journal of Food Science and Technology
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• v.47 no.3
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• pp.293-298
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• 2015

This study aimed at characterizing the rheological properties and molecular weight of tara gum fractionated with ammonium sulfate. Tara gum was separated into six fractions (F1-F6) at different concentrations of ammonium sulfate, ranging from 12.21 to 28.67% (w/w). The yield of the tara gum fractions ranged between 4.98 and 17.47%, and their intrinsic viscosity ranged from 9.38 to 12.44 dL/g. The highest values of Huggins coefficient (k') and viscosity-molecular mass were observed in fraction F3. The shear viscosity of the tara gum fractions was measured by a cone-plate viscometer, clearly showing shear thinning behavior. Size-exclusion chromatography results showed that the molecular weight ranged between 635.42 and 776.71 kg/mol, and the F3 fraction exhibited higher values of molecular weight.

• Korean journal of applied entomology
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• v.38 no.2
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• pp.101-107
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• 1999

Queens of Korean native bumblebee species, Bombus ignitus were collected from the field in the spring of 1998 to investigate their ecological characteristics and reared under the laboratory conditions; 3 0 f 1$^{\circ}$C, 55 25% of relative humidity and darkness. As a result, 94.4% of the queens laid eggs in 6.00f 2.41 days after the field collection. The first worker and the first drone from the egg cell of the collected queens appeared in 18.90 f 1.16 and 68.96 f 3.94 days, respectively. In the colony foundation, 86.1% of the collected queens founded their colony, and 96.8% of them produced new queens in 71.14f 6.88 days. The life span of the colony-founded queen covered for 86.90f24.35 days, whereas that of non-colonized queen for 15.67 f 7.37 days. One colony sized as big as 987.82f 145.84 in number, composing of workers (188.79f 18.23), drones (691.10f 159.24) and queens (107.93 f47.48). Copulation lasting time of queen and drone took 23.00f 7.33 minutes in average. In a new queen emergence, there were two patterns; single peak type of new queen emergence in 12.31 k6.95 days and two peaks type of it in 74.00f 17.61 days. The number of eggs per egg cell of new queen averaged as 8.86f 4.00 grains and an egg period covered 3 days after oviposition. An egg cell sized as 7.15 f0.88 mm in a width, 7.79 f 1 .l 1 mm in a length and 3.33 f 0.23 mm in a height. An egg shaped as banana and sized as 1.22 f 0.09 mm in a width and as 3.5 1 f 0.21 mm in a length, weighing as 2.70 + 0.30 mg.

• Journal of the Korean Ceramic Society
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• v.33 no.2
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• pp.177-182
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• 1996

strontium titanate (SrTiO3) thin films deposited on Pt/MgO were prepared by Plasma Enhanced Metal Orgainc Chemical vapor Deposition (Pe-MOCVD). The crystallinity of SrTiO3 thin films increased with increasing depo-sition temperature and SrF2 second phase disappeared at 55$0^{\circ}C$ The films showed a dielectric constant of 177 and a dissipation factor of 0.0195 at 100 kHz. The variation of capacitance of the films with applied voltage was small showing paraelectric properties. The charge storage density and leakage current density were 40fC/${\mu}{\textrm}{m}$2 and 3.49$\times$10-7 A/cm2 at 0.25 MV/cm, respectively.

• Communications of the Korean Mathematical Society
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• v.33 no.3
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• pp.889-899
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• 2018

In this paper, we present some upper bounds for unitarily invariant norms inequalities. Among other inequalities, we show some upper bounds for the Hilbert-Schmidt norm. In particular, we prove $${\parallel}f(A)Xg(B){\pm}g(B)Xf(A){\parallel}_2{\leq}{\Large{\parallel}}{\frac{(I+{\mid}A{\mid})X(I+{\mid}B{\mid})+(I+{\mid}B{\mid})X(I+{\mid}A{\mid})}{^dA^dB}}{\Large{\parallel}}_2$$, where A, B, $X{\in}{\mathbb{M}}_n$ such that A, B are Hermitian with ${\sigma}(A){\cup}{\sigma}(B){\subset}{\mathbb{D}}$ and f, g are analytic on the complex unit disk ${\mathbb{D}}$, g(0) = f(0) = 1, Re(f) > 0 and Re(g) > 0.

• Journal of the Korean Applied Science and Technology
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• v.3 no.1
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• pp.15-22
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• 1986

The purpose of this study was to investigate the effects of garlic diet on blood coagulation in cholesterol-fed rats. 36 male rats were divided into six groups and fed experimental diet for three weeks. Two-levels (2% and 4%) of fresh and boiled garlic were supplemented to the stock diet with 2% cholesterol and 0.25% bile salt for the experimental diet. After the rats fed with experimental diets during 3 weeks, the whole blood coagulation time, the content of plasma fibrinogen, the fibrinolytic activity and the prothrombin time were measured. The results are summarized as follows; 1. Garlic diet have no influence on body weight and food consumption in rats. 2. In the case of cholesterol-fed group, the whole blood coagulation time was decreased 24.3% compared with the normal group(A). But garlic diet group(C) was similar to the normal group(A) and groupD-F was increased 4.9-11.5%. 3. The content of plasma fibrinogen of cholesterol-fed group was higher 114.5% than that of normal gropu(A). In the garlic diets(C-F) the contents of plasma fibrinogen were increased 33.1-63.8%. 4. The fibrinolytic activity of cholesterol diet was decreased 16.2% compared with the normal group(A) but was increased 10.9-44.5% compared to the garlic diets(C-F). 5. The prothrombin time of cholesterol-fed group was decreased 8.9% compared with normal group(A) but was increased 8.0-46.3% in garlic diets(C-F). As mentioned above, the garlic diets increased whole blood coagulation time, prothrombin time and fibrinolytic activity and decreased the content of fibrinogen. For that reason it is thought that the garlic diets have a anticoagulation effect regulating the fibrinogen synthesis in liver.

• Textile Coloration and Finishing
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• v.33 no.1
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• pp.31-39
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• 2021

In this study, the dyeing properties of supercritical fluid dyed nylon fabrics were investigated which use two types of dyes for dyeing nylon. For other dyeing conditions were referred to related literature, and dyeing was performed with different dyeing concentrations. Dyeability was confirmed through measurement of washing fastness and color coordinate, and a calibration curve of each dye was drawn up and the absorbance of the residual dye was measured to confirm the amount of residual dye and the dye exhaustion rate at the corresponding concentration. As a result of color difference measurement, the color intensity increased as the concentration increased, but the increase was insignificant at high concentration. This tendency was more obvious in C.I. Disperse Orange 155 than in C.I. Disperse Yellow 42. The dye absorption rate also decreases as the concentration increases, but at 0.85% o.w.f concentration, C.I. Disperse Yellow 42 was 97.29% and C.I. Disperse Orange 155 was 93.77%. For both dyes, the wash fastness dropped by 0.5 to 1 class from the sample that was dyed at a concentration of 0.5% o.w.f in the wash fastness test.

• Journal of the Korean Society for Heat Treatment
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• v.13 no.6
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• pp.383-390
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• 2000

The static creep behaviour of AlSl 420F stainless steel was investigated over the temperature range of $540{\sim}585^{\circ}C$ and the stress range of $13{\sim}19kg/mm^2$ (127.4~186.2MPa). Constant stress creep tests were carried out in the experiment. Measured stress exponent, n, for the creep deformation of the alloy under the given conditions was found to vary at the range of 9.59, 9.15, 8.78, and 8.53 for the temperature of 540, 555, 570, and $585^{\circ}C$ respectively. The activation energy, Qc, for the creep deformation was 106.42, 102.58,97.81, and 94.58 kcal/mole for the stress of 13, 15, 17, and $19kg/mm^2$, respectively. Lason-Miller parameter, P, for the crept specimens for AlSl 420F stainless steel was measured as $P=T(log\;t_T+21)$. The empirical static creep rate obtained by the regression analysis was as follows. $${\varepsilon}={\exp}[(3.79{\times}10^{-2}{\sigma}+2.722)T-3.0747{\sigma}+28.109]{\times}{\sigma}^{(-2.367{\times}10^{-2}T+22.33)}{\exp}\left[-\frac{(-2.015{\sigma}+132.580){\times}10^3}{RT}\right]$$ The failure plane were observed, intergranular fracture was dominated by r (round) type crack over the experimental range.

• Journal of the Mineralogical Society of Korea
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• v.16 no.1
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• pp.1-17
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• 2003

The chemical composition of the arsenopyrite Ib adjoining“triple mutual contact”arsenopyrite + pyrite + hexagonal pyrrhotite may serve as a useful geothermometer in Stage II. In this study it corresponds to temperature T=33$0^{\circ}C$ and f( $S_2$)=10$^{-9.5}$ atm. And the pyrite-hexagonal pyrrhotite buffer curve indicates the probable range of the two variables; T= 315∼345$^{\circ}C$, and f( $S_2$)=10$^{-1}$0.5/∼10$^{-9}$ atm. The present antimony-bearing arsenopyrite (arsenopyrite Ic) is characterized by relatively high content of antimony, ranging from 4.95 to 8.91 percent Sb by weight and excess of iron and deficiency of anions are evident. Such a high antimonian arsenopyrite has never been known within single grain. But being the high content of antimony as in the arsenopyrite Ic, it does not serve as a geothermometer. The results of microprobe analyses for four pairs of asenopyrite and sphalerite in Stage III indicate the temperature range from 310 to 34$0^{\circ}C$, and sulphur fugacity range from 10$^{-10}$ ∼10$^{-9}$ atm. These values seem to correspond with those inferred from the Fe-As-S system.m..

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.8
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• pp.1034-1042
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• 2010

This study aimed to determine the optimum dietary crude protein level in a typical diet for fattening pigs fed ad libitum under normal climate conditions in Central Vietnam. One hundred and ninety two gilts of Mong Cai local breed (MC), $F_1$ Large White${\times}$Mong Cai and $F_2$ crossbreds of (Landrace${\times}$Mong Cai)${\times}$Large White were used. At the start of the experiment, Mong Cai pigs weighed 12 kg at 11 weeks of age, $F_1$ pigs 12.1 kg at 8 weeks of age and $F_2$ pigs 12.2 kg at 8 weeks of age. Four diets differing in crude protein (CP) content (10.1, 13.1, 16.1 and 18.9% in DM) were formulated from rice bran, corn meal, cassava meal and fish meal. Calculated digestible energy content of the diets ranged from 13.5 to 13.8 MJ per kg DM. Pigs were housed individually in pens of $2.5\;m^2$ each and had ad libitum access to feed in a trough as well as water in bowls. The final weights after a growing period of 150 days were 66, 86 and 96 kg for MC, $F_1$ and $F_2$, respectively. Feed intake of MC pigs was highest at 13.1% CP while $F_1$ and $F_2$ had the highest feed intake at 16.1% CP. The results showed that for MC the maximum gain was obtained at levels between 13 to 16% CP. For the $F_1$ the maximum gain was at dietary protein levels of 16-17%. For $F_2$ the max gain was obtained at CP levels of 16 to 18%. Feed conversion was highest in MC pigs (~4.0) followed by $F_1$ (~3.3) and $F_2$ (~3.1), and within genotypes was lowest at the optimum CP level (p<0.05). Back fat thickness in MC (33.1 mm), $F_1$ (23.0 mm) and $F_2$ (20.5 mm) pigs was different and within genotypes was the lowest at intermediate CP levels. In conclusion, increasing the dietary crude protein contents in practical diets for pigs in Vietnam can increase production on small holder farms. Optimal performance for MC, $F_1$ and $F_2$ pigs is achieved at different dietary crude protein contents.

• Journal of Life Science
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• v.25 no.3
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• pp.323-328
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• 2015

The study of microbial diversity and richness in soil samples from a volcanic island named Ulleungdo, located east of South Korea. The soil bacterial communities on the Ulleungdo were analyzed using pyrosequencing method based on 16S rRNA gene. There were 1,613 operational taxonomic units (OUT) form soil sample. From results of a BLASTN search against the EzTaxon-e database, the validated reads (obtained after sequence preprocessing) were almost all classified at the phylum level. Proteobacteria was the most dominant phylum with 48.28%, followed by acidobacteria (26.30%), actionbacteria (6.89%), Chloroflexi (4.58), Planctomycetes (4.56%), Nitrospirae (1.83%), Bacteroidetes (1.51%), Verrucomicrobia (1.48%), and Gemmatimonadetes (1.11%). α-proteobacteria was the most dominant class with 36.07% followed by Acidobacteria_c (10.65%), Solibacteres (10.64%), δ-proteobacteria (4.42%), γ-proteobacteria (4.29%), Planctomycetacia (4.16%), Actinobacteria_c (4.00%), Betaproteobacteria (3.50%), EU686603_c (2.97%), Ktedonobacteria (2.91%), Acidimicrobiia (1.32%), Verrucomicrobiae (1.27%), Gemmatimonadetes_c (1.11%), Sphingobacteria (1.09%), and GU444092_c (1.06%). Bradyrhizobiaceae was the most dominant family with 22.83% followed by Acidobacteriaceae (10.62%), EU445199_f (5.72%), Planctomycetaceae (4.03%), Solibacteraceae (3.63%), FM209092_f (3.58%), Steroidobacter_f (2.81%), EU686603_f (2.73%), Hyphomicrobiaceae (2.33%), Ktedonobacteraceae (1.75%), AF498716_f (1.46%), Rhizomicrobium_f (1.03%), and Mycobacteriaceae (1.01%). Differences in the diversity of bacterial communities have more to do with geography than the impact on environmental factors and also the type of vegetation seems to affect the diversity of bacterial communities.