• Journal of Ocean Engineering and Technology
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• v.7 no.2
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• pp.131-140
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• 1993

To study the corrosion fatigue begavior of T.M.C.P. steel, the rotary bending fatigue test with the change of concentration of NaCl solution was carried out. Fatigue life in the corrosion environment is decreased markedly in comparision with that in the air. Fatigue limit in the air was about 225 MPa. In case of 3.5% NaCl solution fatigue life could be expressed as .sigma./sub f/=10,392 * (N/sub f/)/sup -o.2923 . According to the paris's rule, crack growth rates could be expressed as da/dN=2.62.*10/sup -7/ .DELTA. K/sup 1.09/(3.5% NaCl solution), da/dN=1.95 *10/sup -7 .DELTA. K/sup 1.05/(1% NaCl solution), da/dN=2.62 * 10/sup -7/.DELTA./sup 0.72/(0.01% NaCl solution) with da/dN expressed in mm/cycle and .DELTA.K in MPa.GAMMA.m. The crack growth rate in the corrosion environment was highest under 3.5% NaCl solution.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.25 no.8
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• pp.664-669
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• 2012

Nano-structured one-dimensional $Na_2Ti_6O_{13}$ particles were synthesized by a molten salt process. Effects of processing parameters on the microstructure and band gap energy of the $Na_2Ti_6O_{13}$ powder were studied in this paper. For the synthesis of the $Na_2Ti_6O_{13}$ particles, two different raw materials of tubular shaped Na-titanate (Na-TiNT) and spherical shaped $TiO_2$ were utilized. Synthesizing with the raw material of Na-TiNT, around 70nm thick 1D-$Na_2Ti_6O_{13}$ with the bandgap energy of 3.5 eV was obtained at $810^{\circ}C$. Below $810^{\circ}C$ or without the presence of NaCl, 1D-$Na_2Ti_6O_{13}$ was in a relatively short in length and agglomerated state. With the processing temperature increased, the thickness of the 1D-$Na_2Ti_6O_{13}$ was also observed to be increased. On the other hand, when $TiO_2$ was employed as a raw material, the mixed amount of $Na_2CO_3$ played an important role in transforming the morphology and phase of the raw material, affecting the bandgap energy of the synthesized product. Specific surface area of the synthesized 1D-$Na_2Ti_6O_{13}$ was significantly affected by the raw and mixed materials as well as processing temperature. When Na-TiNT was processed at $810^{\circ}C$ with NaCl, the specific surface area of the 1D-$Na_2Ti_6O_{13}$ showed the best value of 30.63 $m^2/g$.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.12
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• pp.1742-1752
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• 2013

A basal diet (0.8 g/kg dNa) was formulated in which each of the two sources ($NaHCO_3$ and $Na_2SO_4$) were supplemented in such a way to attain four levels (1.7, 2.6, 3.5, and 4.4 g/kg) of total dNa, respectively, under $4{\times}2$ factorial arrangement. Eight dietary treatments were replicated four times, with 40 birds in each replicate (n = 1,280). The diets supplemented with $Na_2SO_4$ to attain higher levels of dNa showed highest BW gain and feed intake (FI) during d 1 to 10 (interaction effects) while 2.6 g/kg dNa exhibited improved BW gain and gain:feed (FG) during d 11 to 20. Linear rise in daily water intake (DWI) was associated with diets containing increasing dNa during d 1 to 42 ($p{\leq}0.036$). During the first 10 d, DWI:FI was found highest in $NaHCO_3$ diets while $Na_2SO_4$ diets showed highest DWI:FI during last 10 d of the experiment ($p{\leq}0.036$). Increasing dNa and changing $Na_2SO_4$ with $NaHCO_3$ salt increased pH and resulted in poor growth performance. Dressing weight ($p{\leq}0.001$) and abdominal fat ($p{\leq}0.001$; quadratic effect) were reduced, whereas breast ($p{\leq}0.001$) and thigh (p<0.001) weights were aggravated with increasing dNa (linear effects). Present findings suggested higher levels of dNa from $Na_2SO_4$ as the supplemental salt in broiler diets would produce better growth performance, especially in first ten days of life, and improve carcass and body organ characteristics.

• Journal of Animal Science and Technology
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• v.56 no.1
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• pp.4.1-4.7
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• 2014

The effect of sodium and sodium salts on carcass and body organ characteristics of broilers under a four phase feeding program were investigated. A basal diet (0.08% dNa with NaCl) was formulated and one of two sources of dNa ($NaHCO_3$ and $Na_2SO_4$) were supplemented to obtain four different percentages of dNa (0.17, 0.26, 0.35, and 0.44%) for each treatment. There was a linear decrease in dressing percentage (DP) with source ${\times}$ level interaction ($p{\leq}0.001$), while there was a linear increase in breast yield and thigh yield with increasing dNa supplementation ($p{\leq}0.001$). Chicks fed 0.35% $NaHCO_3$ and 0.44% dNa $Na_2SO_4$ supplemental salts had lower abdominal fat ($p{\leq}0.04$). Chicks that received increasing levels of dNa (from 0.17 to 0.44%) showed increasing gizzard weight ($p{\leq}0.02$) and decreasing spleen weight ($p{\leq}0.02$). When both salts were supplemented at 0.26% dNa, the chicks showed their lowest bursa weight ($p{\leq}0.001$). Consequently, chicks at higher dNa showed an increase in breast and thigh meat yield, and increasing capacity of their digestive organ. The higher levels of dNa should be tested with other cations and anions to fully understand acid base homoeostasis.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.2
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• pp.100-104
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• 2004

This study was conducted to investigate the effect of the salinity on growth, inorganic ion content, and photosynthetic rate ($\textrm{P}^{N}$) in Korean ginseng (Panax ginseng C.A. Meyer) with complex fertilizer (CF) and NaCl concentrations. The salinity was applied to plant using NaCl and CF, and controlled an EC as 0.0, 1.0, 2.0 and 3.0 dS $\textrm{m}^{-1}$. The salinity treated three times at 35, 42 and 49 d after transplanting. The leaf area in different electrical conductivity (EC) decreased only the higher NaCl 1.0 dS $\textrm{m}^{-1}$. The root growth increased with CF and especially, it was two times higher at 3.0 dS $\textrm{m}^{-1}$ than that of control. But the root growth sharply decreased with NaCl compared to CF. The light saturation point of Korean ginseng was around 100 $\mu\textrm{mol}\;\textrm{m}^{-2}\textrm{s}^{-1}$ photosynthetically active radiation (PAR), and $\textrm{P}^{N}$ increased as CF increased but decreased with NaCl especially at the late growth stage. The $\textrm{Na}^{+}$ content in Korean ginseng increased sharply with NaCl.

• Journal of Life Science
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• v.31 no.3
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• pp.356-365
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• 2021

Recently, we sequenced the entire genome of a freshwater agar-degrading bacterium Cellvibrio sp. KY-GH-1 (KCTC13629BP) to explore genetic information encoding agarases that hydrolyze agarose into monomers 3,6-anhydro-L-galactose (L-AHG) and D-galactose. The KY-GH-1 strain appeared to possess nine β-agarase genes and two α-neoagarobiose hydrolase (α-NABH) genes in a 77-kb agarase gene cluster. Based on these genetic information, the KY-GH-1 strain-caused agarose degradation into L-AHG and D-galactose was predicted to be initiated by both endolytic GH16 and GH86 β-agarases to generate NAOS (NA4/NA6/NA8), and further processed by exolytic GH50 β-agarases to generate NA2, and then terminated by GH117 α-NABHs which degrade NA2 into L-AHG and D-galactose. More recently, by employing E. coli expression system with pET-30a vector we obtained three recombinant His-tagged GH50 family β-agarases (GH50A, GH50B, and GH50C) derived from Cellvibrio sp. KY-GH-1 to compare their enzymatic properties. GH50A β-agarase turned out to have the highest exolytic β-agarase activity among the three GH50 isozymes, catalyzing efficient NA2 production from the substrate (agarose, NAOS or AOS). Additionally, we determined that GH117A α-NABH, but not GH117B α-NABH, could potently degrade NA2 into L-AHG and D-galactose. Sequentially, we examined the enzymatic characteristics of GH50A β-agarase and GH117A α-NABH, and assessed their efficiency for NA2 production from agarose and for production of L-AHG and D-galactose from NA2, respectively. In this review, we describe the benefits of recombinant GH50A β-agarase and GH117A α-NABH originated from Cellvibrio sp. KY-GH-1, which may be useful for the enzymatic hydrolysis of agarose for mass production of L-AHG and D-galactose.

• The Bulletin of The Korean Astronomical Society
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• v.40 no.1
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• pp.48.2-48.2
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• 2015

van Dokkum and Conroy revisited the strong Na I lines at $8200{\AA}$ found in some giant elliptical galaxies and interpreted it as evidence for bottom-heavy initial mass function. Jeong et al. later found a lot of galaxies showing strong Na D doublet absorption line at $5900{\AA}$ (Na D excess objects; a.k.a. NEOs) and showed that their origins can be different for different types of galaxies. While the excess in Na D seems related with interstellar medium in late-type galaxies, smooth-looking early-type NEOs suggest no compelling sign of ISM contributions. To test this finding, we measured doppler shift in the Na D line. We hypothesized that ISM is more likely to show blueshift due to outflow caused by either star formation or AGN activities. In order to measure the doppler shift, we tried both Gaussian and Voigt functions to fit each galaxy spectrum near the Na D line. We found that Voigt profiles reproduce the shapes of the Na D lines markedly better. Many of late-type NEOs clearly show blueshift in their Na D lines, which is consistent with the former interpretation that the Na D excess found in them is related with star formation-caused gas outflow. On the contrary, early-type NEOs do not show any notable doppler component, which is also consistent with the interpretation of Jeong et al. that the Na D excess in early-type NEOs is likely not related with ISM activities but purely stellar in origin.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.1
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• pp.115-120
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• 2006

To convert the soybean curd residue (SCR) to functional food ingredient, alkaline fermentation of SCR was performed by Bacillus firmus NA-1 and Bacillus subtilis GT-D for 22 hr at $42^{\circ}C$. The micronized full-fat soy flour (MFS) was fortified to reduce the moisture content as well as to supply protein source. The mucilage and flavor productions in the fermented SCR were enhanced by the fortification of $20\%$ MFS. The peptide production from the SCR fermented with B. subtilis GT-D substantially increased when judged by the detectable amount of tyrosine $(480\;mg\%)$. The production of fibrinolytic enzyme was increased by the fermentation for 22 hr, indicating the relative activity of $62\%$ (B. firmus NA-1) and $47\%$ (B. subtilis GT-D), respectively. The SCR fermented by B. firmus NA-1 and B. subtilis GT-D indicated the consistency of $1.95\;Pa{\cdot}s^n\;and\;0.21\;Pa{\cdot}s^n$, respectively. After freeze-drying, the protease activity (615 unit/g) and a-amylase activity (180 unit/g) were obtained from SCR fermented by Bacillus firmus NA-1 and Bacillus subtilis GT-D, respectively.

• Korean Journal of Poultry Science
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• v.47 no.2
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• pp.75-82
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• 2020

This study intended to investigate the growth performance and meat quality traits in broilers fed different regimens of NaCl over a period of 35 days. Seven hundred and fifty 1-day-old chicks (Cobb 500) were randomly assigned to five NaCl feeding regimens to obtain three replicates for each regimen. Broilers in CON group were provided with concentrations of 0.35% NaCl for the duration of the experimental period. The other groups were provided with two concentrations of NaCl (0.45% and 0.55%) under two durations, namely: 1) 1~28 d: 0.45% or 0.55% NaCl for 28 days then CON; and 2) 1~35 d: 0.45% or 0.55% NaCl for 35 days. Broilers fed 0.55% NaCl for 1~35 d showed improved (P<0.05) growth performance compared with broilers fed the CON regimen. Moreover, higher water holding capacity of breast meat was shown by the broilers fed 0.55% NaCl for 1~28 d when compared with that in broilers fed the CON diet (P<0.05). Broilers fed 0.45% NaCl showed an increase (P<0.05) in the lightness of the meat over CON diet and the 0.55% NaCl diet. In addition, broilers offered CON had the highest redness value and highest crude ash content in the breast meat (P<0.05). Feeding 0.45% NaCl for 1~35 d and 0.55% NaCl for 1~28 d resulted in a higher (P<0.05) protein content in breast meat. In conclusion, broilers fed diets with 0.55% NaCl for 1~35 d showed improved growth performance as well as water holding capacity and protein content of the breast meat.

• Journal of Environmental Science International
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• v.11 no.1
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• pp.75-83
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• 2002

The removal performance of copper ion was studied using Na-P1 zeolites synthesized from Jeju scoria. The scoria which is found in large amounts in Jeju Island, was sampled at four regions, Jeju-shi Bonggae-dong(A). Pukcheju-gun Hanlim-eup Sangmyong-ri Mangoreum(B), Pukcheju-gun Hanlim-eup Keumag-ri(C) and Namcheju-gun Andeok-myun Dongkwang-ri(D). Synthetic Na-P1 zeolites used in this study were more effective than natural zeolite and scoria for the removal of copper ion. The removal performances of copper ion decreased in the order of Na-P1(D) > Na-P1(C) > Na-P1(B) > Na-P1(A) among Na-P1 synthesized from the scoria according to region. These results showed the same trend with cation exchange capacity(CEC) for each synthetic zeolite, i.e., the synthetic Na-P1 zeolite with a higher CEC showed a higher removal performance. The effective diffusion coefficients of copper ion by synthetic Na-P1 zeolites were one hundred and ten times higher than those by a pure zeolite 4A and the zeolite A synthesized from coal fly ash, respectively.