• 환경위생공학
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• 제10권1호
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• pp.132-141
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• 1995

The objectives of this study was to find the effect of zinc salt treated with coconut activated carbon and the effect of humic substance. The bottle- Point technique was used in determining the Freundlich isotherm equation. The adsorptive capacity of granular activated carbon was reduced when humic substance are present. Coconut activated carbon was coated with 0.0001 N zinc chloride decreased the BET surface area but increased the adsorptive capacity more than coconut activated carbon not coated with zinc chloride. The adsorptive capacity of TCE in coconut activated carbon coated with higher concentration of zinc chloride was reduced but increased in the solution containing humic substance when the coconut activated carbon was coated with 0.01 N- zinc chloride. The zinc salt coated with coconut activated carbon did not Increase the adsorptive velocity of coconut activated carbon.

• Bulletin of the Korean Chemical Society
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• 제22권9호
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• pp.1019-1022
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• 2001

Negatively charged functional organic molecules such as retinoic acid, ascorbic acid, indole acetic acid, citric acid, salicylic acid, acidic dye (indigo carmine, Food Blue 1) are intercalatively encapsulated by zinc basic salt (hydrozincite) and layered double hydroxide. Such functional organic-inorganic nanohybrids are realized via coprecipitation reaction involving simultaneous formation of layered inorganic lattice and intercalation of anionic species. The heterostructural nature of these nanohybrids, their particle morphology and textural characterizations are mainly discussed on the basis of Powder X-ray Diffraction and Field Emission Scanning Electron Microscopy results.

• 한국재료학회지
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• 제15권1호
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• pp.47-53
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• 2005

The E.M.F. of the galvanic cell with fused salt was measured to determine the activities of zinc at 720-860 K over the entire composition range of liquid Zn-In and Zn-Sn alloys. The cell used was as follows: $$(-)W{\mid}Zn(pure){\mid}Zn^{2+}(KCl-LiCl){\mid}Zn(in\;Zn-In\;or\;Zn-Sn\;alloy){\mid}W(+)$$ The activities of zinc in the alloys showed positive deviation from Raoult's law over the entire composition range. The activity of cadmium and some thermodynamic functions such as Gibbs free energy, enthalpy and entropy were derived from the results by the thermodynamic relationship. The comparison of the results and the literature data was made. The liquid Zn-In and Zn-Sn alloys are found to be close tn the regular solution. The concentration fluctuations in long wavelength limit, $S_{cc}(o)$, in the liquid alloy were calculated from the experimental results.

• 한국잠사곤충학회지
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• 제45권2호
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• pp.121-125
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• 2003

Dissolution of Antheraea pernyi silk fiber was carried out in a zinc nitrate 6 hydrate (Zn(NO$_3$)$_2$ㆍ6$H_2O$) solution with various dissolving conditions. The solubility was significantly dependent on the concentration of zinc nitrate, dissolving temperature and time. Regenerated A. pernyi silk fibroin powder was obtained through dialysis process to remove chaotropic salt. FTIR and X-ray diffractometer showed that the conformation of regenerated A. pernyi silk powder was sheet structure.

• 환경위생공학
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• 제11권3호
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• pp.79-84
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• 1996

In order to determine the content of heavy metal in common salts, 35 bay salt samples, 7 refined salt samples, 7 fine salt samples, 5 bake salt samples and 5 bamboo bake salt samples were collected from old market in major cities. Heating bay salt 35 samples, it made heating bay salt of $500^{\circ}C$, /TEX>(34 samples), heating bay salt of $1000^{\circ}C$(35 samples). These were analysed for contents of lead(Pb), cadmium(Cd), iron(Fe) and zinc(Zn) by atomic absorption spectrophotometer. The results were as follows : Mean content of lead in bay salts was $0.124{\pm}0.035ppm$ refined salt was $0.130{\pm}0.019ppm$, fine salt was $0.073{\pm}0.036ppm$ bake salt was $0.097{\pm}0.023ppm$, bamboo bake salt was $0.117{\pm}0.020ppm$, heating bay salt was $0.063{\pm} 0.021ppm$ in $500^{\circ}C$, heating bay salt was $0.063{\pm}0.039ppm$ in $1000^{\circ}C$. And bay salt refined salt bamboo bake salt were not significant one another. Mean content of cadmium in bay salts was $0.031{\pm}0.008ppm$ refined salt was $0.032{\pm}0.003ppm$, fine salt was $0.037{\pm}0.005ppm$, bake salt was $0.169{\pm}0.117ppm$ bamboo bake salt was $0.079{\pm}0.052ppm$, heating bay salt of $500^{\circ}C$ was $0.030{\pm}0.029ppm$ heating bay salt of $1000^{\circ}C$ was $0.017{\pm}0.013ppm$. And bay salt refined salt, fine salt were not significant one another. Mean content of iron in bay salts was $1.025{\pm}0, 634ppm$, refined salt was $0.359{\pm}0.163ppm$ fine salt was $0.267{\pm}0.068ppm$, bake salt was $2.929{\pm}1.963ppm$, bamboo bake salt was $5.378{\pm}3.676ppm$, heating bay salt of $500^{\circ}C$ was $0.847{\pm}0.315ppm$ heating bay salt of $1000^{\circ}C$ was $0.991{\pm}0.868ppm$. And bay salt refined salt, fine salt, bake salt, bamboo bake salt were significant one another(p<0, 01). Mean content of zinc in bay salts was $0.253{\pm}0.154ppm$, refined salt was $0.263{\pm}0.091ppm$ fine salt was $0.187{\pm}0.015ppm$, bake salt was $0.166{\pm}0.034ppm$, bamboo bake salt was $0.282{\pm}0.064ppm$, heating bay salt of $500^{\circ}C$ was $0.253{\pm}0.085ppm$, heating bay salt of $1000^{\circ} C$ was $0.242{\pm}0.179ppm$. And bay salt refined salt fine salt, bake salt, bamboo bake salt were not significant one another.

• 대한수의학회지
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• 제25권2호
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• pp.145-148
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• 1985

Nickel toxicity and interactions of nickel with zinc, copper, and lead were studied in glowing chicks fed supplemented diet. Feed intake and growth rate of the chick were reduced by 250mg nickel as a sulfate salt per kg of feed. The toxicity of nickel was decreased by zinc or copper supplementation, but not lead. High nickel feed increased nickel level in kidney and decreased zinc levels in tibia and plasma. However, low zinc levels in tibia and in plasma were reversed by zinc supplementation. Hemoglobin, packed cell volume, and aortic elastin content were increased in chicks fed nickel. These results suggest that nickel toxicity is induced by interference with zinc metabolism.

• 한국재료학회지
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• 제12권4호
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• pp.283-289
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• 2002

The E.M.F of the galvanic cell with fused salt was measured to determine the activities of zinc at 700-820K over the entire composition range of liquid Zn-Cd alloys. The cell used was as follows: (-) W ｜ Zn(pure) $Zn^{2+}(KCI-LiCl)$ ｜ Zn(in Zn-Cd alloy) ｜ W (+) The activities of zinc in the alloys showed positive deviation from Raoult's law over the entire composition range. The activity of cadmium and some thermodynamic functions such as Gibbs free energy, enthalpy, entropy were derived from the results by the thermodynamic relationship. The comparison of the results and the literature data was made. The liquid Zn-Cd alloy is found to be close to the regular solution. The concentration fluctuations in long wavelength limit, $S_{cc}(o)$, in the liquid alloy was calculated from the results.

• 한국해양공학회지
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• 제25권1호
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• pp.32-38
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• 2011

Galvanized steel has gone through a chemical process to keep it from corroding. The steel gets coated in layers of zinc because rust will not attack this protective metal. For countless outdoor, marine, or industrial applications, galvanized steel is an essential fabrication component. The reduction of the corrosion rate of zinc is an important topic. In the past, a very popular way to reduce the corrosion rate of zinc was to use chemical conversion layers based on $Cr^{+6}$. However, a significant problem that has arisen is that the use of chromium salts is now restricted because of environmental protection legislation. Therefore, it is very important to develop new zinc surface treatments that are environmentally friendly to improve the corrosion resistance of zinc and adhesion with a final organic protective layer. In this study, a Urethane solution (only Urethane 20 wt.%; S-700) and an organic/inorganic solution with Si (Si polysilicate 10 wt.% + Urethane 10 wt.%; LRO-317) are used. Based on the salt spray test of 72 h, S-700 and LRO-317 had a superior effect for the corrosion resistance on EGI and HDGI, respectively.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2006년도 전기학술대회논문집
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• pp.271-272
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• 2006

Zinc confers high corrosion resistance by acting as a sacrificial anode, and a zinc coating improves the appearance of steel. Chromate conversion coating (CCC) films are still one of the most efficient surface treatments for steel. Although such films can self-repair via the dissolution of Cr(VI), dissolved Cr(VI) have adverse effects on humans, and the environment. Therefore, we examined the corrosion protection property and morphology of colloidal silica conversion films as an alternative to CCC films. The corrosion behavior was investigated in 3% NaCl solution using electrochemical techniques, including electrochemical impedance spectroscopy, open circuit potential, and the salt spray test(SST). Corrosion was implied by the appearance of red rust on the specimen surface. In corrosion resistance at 3% NaCl solution, red rust appeared at 15-20, 55-70, and 83-98 days on Zn-electroplated steel, colloidal silica conversion-coated specimens, and CCC-coated specimens, respectively. In the salt spray test, the colloidal silica film provided better corrosion protection than CCC films, i.e., red rust appeared at 96 hours on the Zn-electroplated steel sheet, at 432 hours with the CCC films, and at 888 hours with silica conversion coating.

• Corrosion Science and Technology
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• 제7권6호
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• pp.370-374
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• 2008

In this study, we evaluated anti-corrosion properties of both commercial unleaded and lead epoxy primer for automotive substrate before applying to actual painting lines by salt spray test, and cyclic corrosion test, potentiodynamic test and electrochemical impedance spectroscopy. The difference in the corrosion resistance between automotive epoxy primers contained $Bi(OH)_{3}$ and leaded one was investigated. And it was also discussed the effect of zinc phosphate pretreatment to the epoxy primers. The specimen coated epoxy primer contained $Bi(OH)_{3}$ showed 0.5 V higher corrosion potential than that of bare steel. The result of salt spray test did not indicate remarkable difference of corrosion resistance in all specimens above $10{\mu}m$ thickness up to 1200 hours. In the cyclic corrosion test, epoxy primers contained $Bi(OH)_{3}$ on phosphated substrate performed good corrosion properties until 800 hours. The epoxy primer contained $Bi(OH)_{3}$ performed the equivalent corrosion resistance as leaded coating on phosphated steel, but slightly inferior to that of leaded on bare steel. These results show that the pre-treatment of zinc phosphate is effective as well as pigment changing in performing anti-corrosion properties in automotive bodies.