• Bulletin of the Korean Chemical Society
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• v.13 no.3
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• pp.230-235
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• 1992

The conformational analysis has been done for catecholamines (dopamine, norepinephrine, and epinephrine) in the cationic and di-anionic states. The species responsible for adsorption on silver metal surface is anionic deprotonated at hydroxyl groups of catechol moiety, i.e., di-anionic states of catecholamines. This was deduced from Fourier-transform Raman spectra of sodium salts of catecholamines. High resolution proton NMR (400 MHz) spectra of catecholamines in basic and neutral $D_2O$ solution show that the conformations of norepinephrine and epinephrine in the di-anionic states are preferred in gauche, but not for dopamine in the di-anionic state. However the energy difference between trans and gauche of catecholamines in the protonated cationic states is small enough to rotate freely through C-C bond in ethylamine moiety. The conformational calculations using an empirical potential function and the hydration shell model (a program CONBIO) show consistent with above experimental results. The calculations suggest that the species of catecholamines adsorbed on silver metal surface would be in favor of the gauche conformations.

• Korean Journal of Soil Science and Fertilizer
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• v.6 no.3
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• pp.193-197
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• 1973

1. Two desert perennial plant species (Lycium andersonii Gray and Atriplex confertifolia (Torr. & Frem) Wats.) were grown in soil in a glasshouse with different sources of Na ($NO_3{^-}$, $Cl^-$, $H_2PO_4{^-}$) to evaluate their effects upon cation-anion balance in the plants. 2. Each anion greatly increased in leaf with only minor, if any, interactions with other anions 3. The miliequivalent sum of anions measured (N. P. Cl), increased in each plant part with the soil applications. 4. Simultaneously there were usually modest increases in the me. sum of cations. 5. The cation-anion ratio was decreased markedly when $NaNO_3$ was added. The ratio was usually over one. 6. Maximum content of Cl and N in leaves with L. andersonii. was 13.5%, and 6.37% respectively, when each was added. 7. Sodium concentrations were higher for the Atriplex species than for L. andersonii. 8. There were some compensations among other cations as sodium was increased, so that a somewhat constant sum of cations was maintained although there were significant differences among different sources of Na. 9. L. andersonii appeared to be an accumulator of Li.

• 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.

• Applied Chemistry for Engineering
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• v.8 no.6
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• pp.1041-1047
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• 1997

The influence of $\omega$-phenylalkylammonium salt on the critical micelle concentration (CMC) of SDS has been examined using the electric conductivity method. CMC of SDS exhibited the tendency to decrease with the length of alkyl group of additives. The effect of temperature on CMC of SDS in additive solutions has been observed in the range of $18^{\circ}C-50^{\circ}C$. The free energy(${\Delta}G_m^{\circ}$) for the micellization of SDS is negative and the entropy(${\Delta}S_m^{\circ}$) is a large positive value. The enthalpy(ΔHm0is positive in low temperature($18^{\circ}C$) and negative in high temperature($>25^{\circ}C$). In the prensence of organic additives, the micellization of SDS was considered as a spontaneous process and to involve a phase transition. The values of ΔGm0has shown the tendency to increase but the values of ${\Delta}S_m^{\circ}$ and ${\Delta}H_m^{\circ}$ to decrease with the length of alklyl group of additive salts. The changes in ${\Delta}\kappa$(difference of specific conductivity) with increasing mole ratio of additives in the mixed solutions indicated the formation of mixed micelles between SDS and additives. The effect of the length of alkyl chain on the micellization of SDS demonstrated the penetration of organic additives into the palisade layer of the SDS micelle.

• The Korean Journal of Food And Nutrition
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• v.13 no.4
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• pp.319-327
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• 2000

This study was conducted to prolong the edible period of Kimchi by adding chitosan (0.25, 0.5%) and sodium salts of various organic acids(0.01~0.04M citrate, malate, lactate) . The edible period was estimated by measuring changes in pH. titratable acidity(TA), PH/TA ratio, ascorbic acid content and pectin fraction during Kimchi fermentation at 2$0^{\circ}C$. The results were compared by estimating the maturity of Kimchi fermentation. Kimchi with the chitosan showed higher pH and titratable acidity throughout the fermentation period than that without chitosan. The pH decreased during the fermentation in the order of control, 0.25% chitosan, 0.5% chitosan, 0.5% chitosan+Na-citrate, 0.5% chitosan+Na-malate and 0.5% chitosan+Na-lactate. But the titratable acidity increased in the order of control, 0.5% chitosan+Na-malate, 0.25% chitosan. 0.5% chitosan+Na-citrate, 0.5% chitosan and 0.5% chitosan+Na-lactate. The PH/TA ratio decreased in the order of control, 0.25% chitosan, 0.5% chitosan+Na-malate, 0.5% chitosan, 0.5% chitosan+Na-citrate and 0.5% chitosan+Na-lactate. Ascorbic acid content in Kimchi was the highest at the 3rd day and then decreased during fermentation. Ascorbic acid content in Kimchi containing 0.5% chitosan and organic acid salts was higher than others. Alcohol insoluble solids( AIS ) in Kimchi decreased during fermentation in the order of control, 0.25% chitosan, 0.5% chitosan, 0.5% chitosan+Na-palate. 7.5% chitosan+Na-lactate and 0.5% chitosan+Na-citrate. During fermentation, hot water soluble pectin (HWSP) of control increased, whereas HCI soluble pectin (HCISP) decreased. By addition of chitosan, however, the results became reverse. Chitosan addition appeared to be effective in improving preservation quality of Kimchi during fermention. The edible period become extended by using chitosan plus organic acids instead of using chitosan only. Overall. addition of 0.5% chitosan+Na-lactate seemed most effective in prolonging the edible periods during Kimchi fermentation.

• KSBB Journal
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• v.16 no.1
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• pp.48-53
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• 2001

Bovine serum albumin(BSA) was solubilized into the reverse micellar phase consisting of sodium bis(2-ethylhexyl) sulfosuccinate(AOT) and isooctane using the phase transfer method. Of particular interest in this study were the effects of pH and the added salt type and concentration on the solubilization efficiency. When univalent or divalent salts such as KCl, NaCl, $MgCl_2$, or $CaCl_2$ were added to the aqueous phase at a concentration of 0.1 M, maximum solubilization efficiency was attained at a pH ranging from 5 to 7, depending on the added salt type. Increased salt concentration up to 1 M resulted in an increased solubilization efficiency for $CaCl_2$ and NaCl, while the addition of $MgCl_2$ beyond 0.1 M showed an anomalous trend. Further, it was noteworthy that too a large extent the protein precipitated in the interface between the organic and aqueous phases at lower pHs and lower salt concentrations. The size of the reverse micelle water pool was estimated by measuring the molar ratio of the surfactant to the water, $W_0$. Irrespective of pH in the aqueous phase, the resulting value of $W_0$ was almost constant, eg., 20 for $MgCl_2$ . However, the value of $W_0$ decreased with increased salt concentration in the cases of KCl and $CaCl_2$.

• Journal of the Korean Chemical Society
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• v.45 no.2
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• pp.116-120
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• 2001

In order to know the physicochemical properties of magnetized water, the experimental methods of column assay, crystalization of saltsand gypsom have been explored to elucidate the effects of magnetized water on the solubility speed of salts, crystal pattern from salt squeous solutions, and gypsom crystal pattern, respectively. In the column assay for salt solubility the magnetized water showed the decreased initial solubility speed of NaCl and slightly increased initial solubility spped of KCI, however, the maximum solugilities of NaCl and KCI in the magnetized aster were almost same in the double distilled water, respectively. The column assay also indicated that the magnetized water showed the decreased initial solubility speed of urea (CH$_4$N$_2$O), sodium citrate (HOC(CO$_2$Na)-(CH$_2$CO$_2$Na)$_2$-2H$_2$O) and (NH$_4$)$_2$compared to the double distilled water, while slightly increased solubility speed of glycine (NH$_2$CH$_2$COOH), boric acid (H$_3$BO$_3$), MgSO$_4$. Crystalization of 1% or 5% salt aqueous solutions by rapid evaporation disclosed that the magnetized water produced more condensed and bigger crystal structure than the control water. The pattern of gypsom crystal formation also indicated that the magntized water enhanced the crystal formation in the hydration reaction of gypsom plaster compared to the double distilled water. Taken together, it was presumed that the magnetized water showed the different physicochemical properties in the interaction with various salts, especially showed the contrast results between NaCl and KCI.

• Korean Journal of Food Science and Technology
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• v.46 no.3
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• pp.288-294
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• 2014

Penicillin and its salts, including the benzatine, procaine, and sodium salts, have been widely used in human and veterinary medicine. Owing to their low toxicity, they currently form the most important group of antibiotics. However, overdose and abuse of these antibiotics may lead to potential risk in human health. Therefore, this study was conducted to validate the analysis method established by the Korea Food Code in 2012 and to monitor the levels of benzylpenicillin residues in products with reference to the maximum residue level (MRL). Of the 232 product samples tested, benzylpenicillin was detected in 11 livestock products and 2 marine products. Benzylpenicillin concentrations were found to be lower than the MRL in 12 products; however, the concentration of benzylpenicillin was found to be greater than the MRL in 1 pork product. The limit of quantification (LOQ) for benzylpenicillin was found to be 0.001-0.002 mg/kg, with an average recovery of 90.4-115.3%. Calibrations showed good linearity of 0.995 over a range of 0.002-0.05 mg/kg.

• Korean Journal of Food Science and Technology
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• v.22 no.4
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• pp.380-385
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• 1990

This study was conducted to determine the relative saltiness of $MgCl_2,\;K_{2}SO_4$ and KCl and evaluate the sensory characteristics of solutions and Kakdugi (Korean seasoned pickles of cubed radish roots) prepared with reduced amount of sodium chloride by replacement with varying levels of KCI. The relative saltiness of $MgCl_2$ and $K_{2}SO_4$, were $0.11{\sim}0.12(0.115)$ and $0.08{\sim}0.09(0.085)$ respectively, at the reference level of 0.5% NaCl. The relative saltiness of KCI varied from 0.52 to 0.76 as the reference level increased from 0.5 to 2.0% NaCl. The result of sensory evaluation on the mixed solutions of NaCl and KCI indicated that bitterness, metallic flavor and astringency increased with the increased levels of KCI. The addition of KCI slightly increased the firmness of kakdugi but there was no significant difference in firmness by the amount of substitution. Bitterness and off-flavor was enhanced with the increased levels of replacement especially when the level was higher than 50%. Saltiness, sourness and overall desirability decreased as the extent of the replacement increased. There were no significant difference in pH, acidity and firmness measured with Universal Testing Machine. The result of this study indicate that the replacement of NaCl with KCI at not more than 50% does not affect greatly the characteristics of kakdugi.

• Journal of Conservation Science
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• v.17 s.17
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• pp.73-82
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• 2005

The Bunhwangsaseoktop is the oldest stone brick pagoda in Silla Period. The pagoda body is made by piling small brick-shaped stones trimmed from black andesite and the first-story core has a shrine, which is made by granite. In 1915 it was repaired on a large scale, but now is severely damaged. Many kind of the stone decay like flaking, granular disintegration have occurred especially on the granite surface of the pagoda. In this study have been investigated the stone decay type and its cause in relation to efflorescence on the body part. Various analysis show that the deterioration on the granite is due to the same materials that lead to efflorescence on the body stone surface. The soluble salt like sodium nitrate, calcium sulfate and sodium sulfate come from white joint mortar. This salt solution is recrystallized in the outside of the pagoda, but most of them flow down with rain. In This process the porous granite absorbes the dissolved salts with moisture into the inside by capillary action. In order to reduce this problem, therefore, white joint moral is changed with other less soluble materials. And it is necessary to take steps to prevent water from seep into the inside of the stone, because this water dissolves the white joint mortar.