• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2001.05a
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• pp.344-349
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• 2001

This paper was to investigate of a adhesiveness for the plasma sprayed coating materials did salt spray by acoustic emission method in tensile loadings. The powders used for the coating were nickel aluminum composite powder Ni-4,5wt.%Al and titanium dioxide powder Ti02. These powders were coated on a carbon steel S45C by plasma spray method. The salt solution was a 5% NaCl and the salt spray times were 2, 5 and 10 hours respectively. The salt solution penetrated into the surface of the substrate through pore of the coating layer built in the process of plasma spay. Corrosion productions formed on the surface of substrate. The adhesiveness between the substrate and the coating layer is weaken by corrosion and the exfoliation initiated chiefly at the corrosion surface of the substrate. The AE events and energy of the corroded coating specimens decreased as the salt spray times increased.

• Journal of Environmental Health Sciences
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• v.22 no.1
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• pp.1-4
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• 1996

I have conducted two testings to find out which water is better for drinking water. First, I made 20 mM L-DOPA solutions by solving L-DOPA (3,4-Dihydroxyphenylalanine) in tap water, Waters' mineral water and reverse osmotic water. Then I measured activities after adding Tyrosinase (purifide enzyme, step 3), which was extracted from Salanum melongena(mad apple), in each L-DOPA solution. Second, I solved 0.1, 0.5 and 0.9% salt in each 20 mM L-DOPA distilled water to measure activity of each salt solution. The results of the testings are as follows: 1. 10 minutes after adding Salanum melongena(mad apple) tyrosinase in each L-DOPA solution, activity of Waters' mineral water was 0.867 tap water 0.777 and reverse osmotic water 0.742. 2. Activity of Waters' mineral water was higher than that of tap water by 10.4% and higher then reverse osmotic by 14.4%. 3. Activity of Waters' mineral water was much higher than that of 0.9% salt water by 41.8%. 4. The optimum pH of Salanum melongena (mad apple) tyrosinase is 9.0. Most enzymes working in the human metabolism are alkaline and body fluids' pH also alkaline. In conclusion, an alkaline water is believed better than an acidic water for drinking.

• Journal of the Korean Ceramic Society
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• v.27 no.7
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• pp.851-860
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• 1990

The hydrolysis-precipitation reaction of mixed aluminum salt solutions of aluminum sulfate, aluminum nitrate, and urea has been investigated to obtain narrow-sized and unagglomerated fine spherical precipitates of aluminum hydroxide required for coating core particles. The hydrolysis-precipitatin reaction could be controlled to be appropriate to coating processes by usign urea as a pH control-agent. As the concetration of total Al3+ ion and the molar ratio of SO42-/Al3+ in starting solutions became smaller and also as the vol. ratio of water/solution for hydrolyzing mixed aluminum salt solution became larger, the morphology of precipitates tended to be more unagglomerated and spherical, while their size(0.5longrightarrow0.05${\mu}{\textrm}{m}$) to be smaller. The optimum hydrolysis condition for coating processes was to hydrolyze the mixed aluminum salt solution, in which the molar ratio of SO42-/Al3+ was 0.75, while the amount of water corresponding to the vol. ratio of water/solution of 15. The precipitate was the aluminum hydroxide which sulfate ions were strongly adsorbed on and the maximum yield in the hydrolysis-precipitation reaction was about 20%.

• Macromolecular Research
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• v.12 no.3
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• pp.263-268
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• 2004

We have synthesized a water-soluble polyimide precursor, poly(amic acid) amine salt (PAD), from pyromellitic dianhydride (PMDA), 4,4'-oxydianiline, and N,N -dimethylethanolamine (DMEA) and have investigated in detail its properties with respect to the degree of salt formation (D$\_$sf/). The maximum value of D$\_$sf/ we obtained upon precipitation of the precursor solution into acetone was 79%. We synthesized a PAD having a D$\_$sf/ of 100% (PAD100) by the solid state drying of an organic solution. The precursors showed different solubility depending on the D$\_$sf/ to make up to 4 wt% solutions in water containing a small amount of DMEA. PAD100 is completely soluble in pure water. We investigated the imidization behavior of PAD in aqueous solution using various spectroscopic methods, which revealed that PAD 100 has faster imidization kinetics relative to that of the poly(amic acid)-type precursors. The resulting polyimide films prepared from an aqueous precursor solution possess almost similar physical and thermal properties as those prepared from N-methyl-2-pyrrolidone(NMP) solution. Therefore, we have demonstrated that PAD can be used as a water-based precursor of polyimide; this procedure avoids the use of toxic organic solvents, such as NMP.

• Journal of the Korean Chemical Society
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• v.19 no.2
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• pp.142-146
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• 1975

The formation of iron oxide hydroxide in a ferrous sulfate was studied in different contents of iron in the solution at a temperature range of 90 to $100^{\circ}C$ under 1${\sim}$3 atmospheres. The Mohr's salt thus formed was hydrolyzed under 1 to 3 atmospheres, in 14 to 72 g/l of iron content in the solution pH 3 or 6 for two hours at 90 to $100^{\circ}C$. The results obtained was as follows; 1) In Mohr's salt solution, as the iron content was increased, with decreasing the concentration of hydrogen ion, the yield of iron oxide hydroxide was gradually increased. 2) When iron content in Mohr's salt solution was 42.81 g/l, 91.5% of iron was recovered in the form of $\alpha$-goethite similar to yellow grade of natural goethite. 3) When $\alpha$-goethite obtained was calcined of $500^{\circ}C$, it was turned into ${\alpha}$-ferric oxide with a redish brown colour.

• The Korean Journal of Ecology
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• v.2 no.1
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• pp.31-37
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• 1978

The salt accumulation on the soil surface can be mathematically described. Although the movement of salts in soil solution is expressed in terms of mathematical model, which has certain limitations in practical application, except the exchangeable and absorbable state salts in soil solution. This model is illustrated by analyticl experiments in which evaporation from the bare soils, transpiration of plants and rainfall are required. Agreement between the model and the measured data was satisfactory, which validating the salt accumulation theory on the soil surface.

• Journal of Nutrition and Health
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• v.16 no.1
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• pp.21-26
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• 1983

For the purpose of study on optimal gustation of salt 108 patients with hypertension(61 cases of male, 47 cases of female) were studied. And also 48 patients with non-hypertensive heart diseases and pulmonary diseases (20 cases of male, 28 cases of female ) and apparently healthy subjects (107 cases of male, 20 cases of female) were studied as control group. By adding salt into 3% rice boiled powder solution the 0.1%, 0.25% 0.5%, 0.75% and 1 % salt solutions were prepared respectively. Allowed subject to taste all above solution in landed and to point out the optimal salty taste of each subject. There were no significant difference in optimal gustation of salt among the hypertensive patients and control group. The optimal salt gustation of hypertensive patients with low salt diet was slightly lower than those with free diet The optimal salt gustation was higher in old aged persons regardless of diseases.

• Journal of Powder Materials
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• v.10 no.2
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• pp.136-141
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• 2003

In the present study, $TiO_2$ imbedded copper matrix powders have been successfully prepared from the ($CuSO_4+TiO_2+Zn$) composite salt solution. The composite $Cu/TiO_2$ powders were formed by drying the solution at $200{\sim}~400^{\circ}C$ in the hydrogen atmosphere. Photocatalytic characteristics was evaluated by detecting TOC (total organic carbon) amount with TOC analyzer (model 5000A Shimadzu Co). Phase analysis of $Cu/TiO_2$ composite powders was carried out by XRD, DSC and powder size was measured with TEM. The mean particle size of composite powders was about 100 nm and a few zinc and copper oxide phases was included. The reduction ratio of TOC amount was 60% by the composite $Cu/TiO_2$ powders under the UV irradiation for 8 hours.

• Korean Journal of Soil Science and Fertilizer
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• v.28 no.3
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• pp.233-240
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• 1995

Fick's diffusion equation was transformed into algebraic subsidiary equation with its initial and boundary conditions through Laplace transformation, and the subsidiary equation was transformed back on the basis of Burington's table of inverse transformations so that it became the solution of Fick's equation. The initial and boundary condition was for upward diffusion of salts into flooding water of constant depth from uniform polder soil of infinite depth containing constant concentration of salt. The derived solution was tested through comparison for its conformability with other solutions of simpler initial and boundary conditions. The importance of shallow transplanting of rice seedlings and salt removing by growing rice was mentioned on the basis of very slow desalting rate by diffusion calculated from the derived solutions.

• Food Science of Animal Resources
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• v.31 no.4
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• pp.497-505
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• 2011

The objective of this study was to examine the effect of hot-boning and soy sauce as a curing agent on the processing properties of beef jerky. Beef jerky was prepared under the following four treatment conditions; Beef jerky with cold-boned beef and salt solution, beef jerky with cold-boned beef and soy sauce solution, beef jerky with hot-boned beef and salt solution, and beef jerky with hot-boned beef and soy sauce solution. Cured meat and jerky containing hot-boned beef had a significantly higher pH, water holding capacity (WHC), moisture content, Myofibrillar fragmentation index (MFI), processing yields, tenderness, and sensorial scores than samples containing cold-boned beef (p<0.05). Regardless of the raw materials, the jerky containing soy sauce had a significantly lower pH, WHC, moisture content, salt content, TBA, CIE $L^*$ and $b^*-$ values, and significantly higher MFI, mechanical tenderness, and sensorial scores (p<0.05). Based on these findings, we concluded that the use of hot-boned meat and soy sauce was the most effective boning method and curing agent during beef jerky processing.