• Transactions of the Korean hydrogen and new energy society
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• v.16 no.4
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• pp.379-385
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• 2005

Effects of Co and Co-P catalysts on the hydrolysis of alkaline $NaBH_4$ solution were investigated. Co and Co-P catalysts were prepared on Cu substrate by electroplating. Hydrogen generation rate of Co-P catalyst was much faster than that of Co catalyst, demonstrating that Co-P had higher intrinsic catalytic activity for the hydrolysis of $NaBH_4$ than Co. Hydrogen generation properties of Co-P catalysts largely depended on cathodic current density and electroplating time because they influenced on the P concentration of the Co-P catalysts. Maximum hydrogen generation rate of Co-P catalyst was 1066 ml/min.g-catalyst in 1 wt.% NaOH + 10 wt.% $NaBH_4$ solution at $20^{\circ}C$, which was obtained at cathodic current density of $0.01\;A/cm^2$ for 130 s.

• Asian Journal of Turfgrass Science
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• v.9 no.4
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• pp.343-350
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• 1995

Samples from the L, F, H and $A_1$ horizons of the Phragmites longivalvis grassland were collected in a delta of the Nakdong River and the removal rates of N, P, K, Ca and Na were investigated. The results obtained in this study can be abstracted as follows; The removal fractions of N, P, K, Ca and Na of the litter were 0.56, 1.22, 1.95, 0.65 and 0.53, respectively. The half times of N, P, K, Ca and Na required for the remove or accumulation of the litter on the grassland floor were 1.23, 0.57, 0.36, 1.06 and 1.32 years, respectively. The increasing order of the turnover parameters of the elements was Na, N, Ca, P and K.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.5
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• pp.485-492
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• 1986

This study was designed to compare the inhibitory effects of algae components such as alginic acid and chlorella extract with the red ginseng saponin and garlic components such as alliin and scordinin on obesity. These components supplemented to basic diet were fed ad libitum to Sprague Dawley rats for 4 weeks, and the inhibitory effects on obesity were evaluated by measuring body weight gain and feed efficiency, the contents of glucose and cholesterol in serum, lipase activity in serum, lipid contents in liver and adipose tissue around epididymis and ovarium, and Lee index, etc. Among the inhibitory effects of these components on obesity, Na-alginate($71\%$) was the most effective (p<0.01), and the others were effective (p<0.001) in the order of scordinin ($76\%$) = chlorella ($76\%$)> alliin ($86\%$) for body weight gain, but Na-alginate ($68\%$) was the most effective, followed by alliin ($79\%$) for feed efficiency (p<0.001). In the inhibitory effects on lipid accumultion in liver and adipose tissue, Na-alginate ($84\%$) among these components was the most effective (p<0.001) in liver, but Na-alginate ($54\%$) was the most effective (p<0.001), followed by alliin ($64\%$), and followed by scordinin ($66\%$) in adipose tissues around epididymis and ovarium (p<0.001). The inhibitory effect on obesity evaluated by Lee index was observed in Na-alginate ($91\%$) only (0.001). The decreasing effects of lipid content in liver by these components were effective in the order of alliin ($40\%$)> saponin ($58\%$)> Na-alginate($62\%$)> chlorella ($64\%$)> scordinin ($74\%$) (p<0.001). G lucose contents in serum were significantly decreased in cases of Na-alginate ($67\%$), saponin ($73\%$), scordinin ($74\%$) and alliin ($83\%$), and cholesterol contents in serum were significantly decreased in cases of Na-alginate ($82\%$), chlorella ($86\%$) and saponin ($89\%$) (p<0.001). The increasing effect of lipase activity in serum was effective in cases of Na-alginate ($109\%$) and saponin ($104\%$), while garlic components such as alliin and scordinin, and chlorella were decreased. It is proved that the inhibitory effect of alginic acid which is the major component of brown algae on obesity was more effective than those of ginseng and garlic components such as saponin, alliin and scordinin.

• The Korean Journal of Physiology
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• v.8 no.2
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• pp.59-66
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• 1974

In recent years much interesting information about the mechanism of the $Na^+-K^+$ activated ATPase has been obtained from investigation of the $K^+-activated$ phosphatase activity which appears to be catalysed by the same enzyme. Also several studies have indicated that a $K^+-activated p-nitrophenylphosphatase activity is intimately related to the ATPase activity. And then the exact relation of p-nitrophenylphosphatase activity to $Na^+-K^+$ ATPase activity is not known. The effects of some ions and drugs on the p-nitrophenylphosphatase activity of the rat brain were investigated and the results were summarized as follows. 1. The p-nitrophenylphosphatase was stimulated markedly by low concentrations of $K^+$, while the activity was activated slightly in the presence of $Na^+$ and oligomycin. 2. Addition of both ATP and $Na^+$ caused a remarkable increase in the activity of the $K^+-dependent$ phosphatase at low concentrations of $K^+$. 3. In the presence of $Na^+$ and low concentrations of $K^+$, oligomycin activated the p-nitrophenylphosphatase. 4. O1igomycin inhibited the stimulation of the enzyme activity caused by $Na^{+}+ATP$. 5. Ouabain inhibited the $K^+-dependent$ p-nitrophenylphosphatase activity more in the presence of ATP and $Na^+$ than in their absence. 6. Quinidine inhibited both $Na^+-K^+$ ATPase and p-nitrophenylphosphatase. These inhibitory effects of the drug were partially antagonized by increasing $K^+$ concentrations. The sensitivity of the $K^+-dependent$ p-nitrophenylphosphatase to quinidine was greater than the that of $Na^+-K^+$ ATPase.

• 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 Society of Food Science and Nutrition
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• v.29 no.6
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• pp.995-1002
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• 2000

In order to Develop a low Na functional kimchi using sea tangle, the Na-binding capacity of alginate in sea tangle along with other dietary fibers was evaluated in vitro. The adding type and amount of the sea tangle that contains alginate in kimhi and characteristics of the sea tangle added kimchi were also studied. Na-binding capacity of various dietary fibers such as cellulose, pectin, gun gum, carageenan, alginates (sodium alginate, alginate, alginate from sea tangle) was measured by equilibrium dialysis method in pH 2 and pH 7 in vitro. Gua gum, carageenan and a group of alginates effectively bound to Na+ Espacially sodium alginate showed high Na-binding capacity of 29.2% in pH of stomach (pH 2.0) and 33.8% in pH of small intestine (pH 7.0), however, the alginate extracted from sea tangle could not bind Na in PH of stomach (pH 2.0), but 27.4% in pH of small intestine (pH 7.0) condition. The content of alginate in sea tangles (dried sea tangle, salted sea tangle and washed salted sea tangle) was 19.8 ~ 22.2% on dry matter basis. The sea tangle added kimchi was prepared with the addition of the flake type (0.5$\times$3 cm) of sea tangle with a quantity of 30% in kimchi from the data of the sensory analysis. The addition of the sea tangle to the kimchi increased the content of soluble dietary fiber, suggesting the Na-binding capacity increased. The sea tangle added kimchi (SK) and sea tangle and fermented anchovy added kimchi (SAK) showed higher levels of reducing sugar and acidity than the control kimchi (CK). In quantitative descriptive analysis (QDA) SK and SAK showed higher score in overall acceptance, and lower score in acidic order than CK, however, SK showed less moldy taste and more fresh acidic taste than SAK.

• Korean Journal of Poultry Science
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• v.15 no.1
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• pp.39-44
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• 1988

This study was undertaken to find out the effect of heating time and temperature, pH and NaCl concentration on heat sensitivity of egg albumen during heat treatment. Sharp increase of the turbidity and rapid decrease of the foaming power were observed when egg albumen was heated at above $60^{\circ}C$. Egg albumen became opaque when it was heated at $60^{\circ}C$ for above 13 minutes or at $65^{\circ}C$ for above 5 minutes. The turbidity was markedly increased at below pH 7 and the foaming power was largely decreased at around pH 4.0 by the heat treatment ($60^{\circ}C$, 5 min). The foam stability was slightly decreased at alkaline pH range by the heat treatment (60t, 5 min). The addition of NaCl up to 0.3M decreased the turbidity. There was no effect of NaCl addition on the foaming power, but the foam stability was decreased by the addition of NaCl at above 0.2M before and after the heat treatment ($60^{\circ}C$, 5 min).

• Journal of Life Science
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• v.17 no.12
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• pp.1616-1621
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• 2007

Off-flavors and odors in fermented cucumbers result from the growth of undesirable microorganisms during the secondary fermentation. Under laboratory conditions using a sterile fermented cucumber slurry medium, the spoilage fermentations were reproduced. Using this system the salt and pH conditions that allow the spoilage to occur were determined by varying the NaCl concentration and pH of the slurry medium. At pH 3, no spoilage was observed, regardless of the salt concentration, while at pH 3.5, pH 4, and pH 4.5, spoilage occurred in the 0 and 2% NaCl samples. For pH 5.0 samples, spoilage products were seen for all NaCl treatments. Based on these results the Preservation Prediction Chart was developed. The Chart may be used for selection of proper pH value and salt concentration for long term storage of fermented cucumber.

• Korean Journal of Food Science and Technology
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• v.22 no.3
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• pp.350-356
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• 1990

Functional properties such as nitrogen solubility, emulsifying property, foaming property, and water and oil absorption of sesame and perilla protein isolates were determined at pH range of 2-10 and ionic strength of 0-0.5M NaCl. Nitrogen solubility of protein isolates in distilled water showed minimum value at pH6.0 in sesame and at pH 4.0 in perilla and soybean protein isolates, and significantly increased above pH 8.0 in all samples. Addition of 0.1M NaCl solution increased nitrogen solubility, however, decreased in 0.5M NaCl solution. Emulsion activities of all the protein isolates showed minimum value at pH 4.0 and increased in 0.1M NaCl solutions while it was reduced in 0.5M NaCl solutions. The perilla protein isolate showed higher emulsion activity than that of soybean and sesame protein isolates at above pH 6.0. Foaming capacities of sesame and perilla protein isolates were lower than soybean protein isolate and generally all of the samples showed higher profiles in NaCl solutions. The foaming stability of soybean isolate decreased abruptly in 10min, while it was slowly decreased for sesame and perilla isolates during initial 30 min. Oil absorption capacity of perilla protein isolate was higher than that of sesame and soybean protein isolates. Water absorption capacity was similar among the three samples studied.

• Korean Journal of Food Science and Technology
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• v.22 no.5
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• pp.569-574
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• 1990

The influence of NaCl and pH on degradation of chicken breast muscle myofibrillar proteins by porcine leukocyte lysosomal proteinases was investigated. The degradation reactions were carried out at $38^{\circ}C$ for 24hours under different conditions. The degradation of myofibrillar proteins by leukocyte lysosomal enzymes at various pH values was limited to partial hydrolysis. Reactions at higher pH values resulted in lower molecular weight degradation products while reactions at lower pH resulted in higher molecular weight degradation products. When NaCl was added into the reaction mixture, enzyme activities of degradation were increased at all pH values studied, as evidenced by NPN-analysis and SDS-PAGE. More severe degradation was observed with higher salt concentration. The concentration of 0.5M NaCl in the reaction mixture gave more degradation of myosin heavy chain by enzyme than that of 0.1M NaCl.