• 전기화학회지
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• 제19권3호
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• pp.57-62
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• 2016

The over-discharging phenomena in sodium-nickel chloride batteries were investigated in relation to decomposition of molten salt electrolyte and consequent metal co-deposition. From XRD analysis, the material deposited on graphite cathode current collector was revealed to be by-product of molten salt electrolyte decomposition. In particular, the result showed that the Ni-Al alloys ($Al_3Ni_2$, $Ni_3Al$ and $Al_3Ni$) were electrochemically deposited on graphite current collectors in line with over-discharging behaviors. It is assumed that the $NiCl_2$ solubility in molten salt electrolytes leads to the co-deposition of Ni-Al alloys by increasing metal deposition potential above 1.6 V (vs. $Na/Na^+$). The cell tests have revealed that the composition of molten salt electrolytes modified by various additives makes a decisive influence on the over-discharging behaviors of the cells. It was revealed that NaOCN addition to molten salt electrolytes was advantageous to suppress over-discharge reactions by modifying the characteristics of molten salt electrolytes. NaOCN addition into molten salt electrolytes seems to suppress Ni solubility by maintaining basic melts. The cell using modified molten salt electrolyte with NaOCN (Cell D) showed relatively less cell degradation compared with other cells for long cycles.

• Journal of Welding and Joining
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• 제32권4호
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• pp.55-62
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• 2014

The use of light-weight Al alloys in the automotive industry is increasing to meet requirements for fuel efficiency and emission reduction. Joining Al alloy to the conventional steel sheet is also very important issue with the increased use of Al alloy, and several joining processes have been introduced to enhance joining strength between dissimilar metals. This paper deals with a galvanic corrosion in the dissimilar metal joining. Salt spray tests up to 2000 hours were conducted on a self-piercing rivet, spot welded, adhesive bonded and weld-bonded joints, and cross-sections and tensile shear strength according the salt spray duration were analyzed at every 500-hour. Self-piercing rivet joint had relative low initial strength but the joint strength did not change regardless of the salt spray duration. The strength of other joints (spot welded, adhesive bonded and weld-bonded joints) decreased with the increase of salt spray duration and the corrosion behaviour of each joint was discussed.

• 한국건설순환자원학회논문집
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• 제9권4호
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• pp.609-616
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• 2021

본 연구에서는 금속염계 무기물인 발수분말과 포졸란계 재료인 천연제올라이트 분말을 사용하여 시멘트 모르타르에 혼입하고 물리적 특성 및 수분에 대한 저항성을 확인하였다. 무기물 금속염계 발수분말을 단독으로 혼입한 시험체에 비해서 천연제올라이트를 동시에 사용한 시험체에서 수분침투실험 및 그에 수반하는 염화물 침투시험에서 높은 저항성을 갖는 것을 확인 할 수 있었다. 금속염계 발수분말을 사용하는 경우 불용성으로 인하여 수분침투저항성이 내부에서 고르게 분산되지 못하고 표면에 국한되었으며 천연제올라이트와 동시에 사용하는 경우 포졸란 반응으로 인해 수화초기의 응결시간이 빠르고 또한 천연제올라이트의 다공성 내부에 발수분말이 부착되어 내부에서도 수분저항성이 일부 생성된 것으로 판단된다.

• 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.

• 공학기술논문지
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• 제4권4호
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• pp.431-436
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• 2011

This study was carried out to reduce the problem during distillation process, which separate U, TRU (TRans Uranium) metal electro deposit, Cd and LiCl-KCl eutectic salt generating from LCC (Liquid Cadmium Cathode) electro winning process. The cadmium recovering apparatus was manufactured to separate for each metal using solid-liquid separation method. The apparatus consists of the first sieve for the separation of U and TRU metal electrodeposit, the second sieve for the separation of LiCl-KCl eutectic salt, cadmium collection basket, and a heating furnace. In addition, the size of each sieve is 2 mm to 3 mm. In this experiment, a metal wire was employed to replace TRU metal electrodeposit and U, which exist actually in a LCC crucible. In the solid state, The LiCl-KCl is separated at 340℃ at which the solid and the liquid of the remaining cadmium and LiCl-KCl eutectic salt coexists in each, after the metal wire separated at 500℃. As a result, it seems that it would be beneficial to set the processing condition in the distillation process with the additional treatment process of cadmium and LiCl-KCl eutectic salt.

• 공업화학
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• 제10권8호
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• pp.1119-1123
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• 1999

본 연구는 용융염계에서 우라늄금속의 건식전해정련공정을 개발하기 위해서 수행되었다. 금속우라늄과 $CdCl_2$와의 반응은 약 3시간이 소요되었으며, 모든 전해전달실험에서 우라늄금속 석출물들은 음극표면에서 성장한 수지상으로 얻어졌다. 수지상의 형태는 부가전압에 따라 변화되었으며, 전류효율은 전류밀도가 증가함에 따라 감소하였다. 반응시간이 6시간 경과된 후에 석출속도는 변화하지 않았으며, 전류밀도가 $100{\sim}150mA/cm^2$이고 교반속도가 약 75 rpm일 때 최대석출속도를 얻었다. 또한, 전류효율은 음극에 있는 나선형 홈의 피치가 작을수록 증가되었다.

• 한국응용과학기술학회지
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• 제35권1호
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• pp.173-185
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• 2018

화학 관능기가 다른 지방산 에스터계, 지방산 금속염 및 아마이드계 분산 및 흐름개선 첨가제가 EPDM과 카본블랙을 충전제로 사용한 고무 배합물의 가류 특성과 가류된 고무 배합물의 기계적 물성 및 노화특성에 미치는 영향을 무니점도계, 레오미터, 경도계, 만능재료시험기 등을 이용하여 측정하였다. $125^{\circ}C$에서 측정된 무니점도는 아마이드계 > 금속염계 > 에스터계 첨가제의 순으로 감소하는 경향을 보였으며, 스코치시간은 에스터계와 금속염계 첨가제는 첨가 유무에 따라 거의 차이가 없거나 조금 늦어지며, 아마이드계 첨가제는 1분 이상 빨라졌다. $160^{\circ}C$에서의 레오미터 측정 결과 가류시간은 금속염계와 아마이드계 첨가제의 경우는 가류반응이 빨리 진행되었다. 델타토크 값은 금속염계와 아마이드계 첨가제가 있는 경우 전반적으로 증가하였으나, 에스터계 첨가제가 있는 경우는 약간 감소하였다. EPDM 배합물의 인장강도는 에스터계 첨가제가 첨가된 경우 크게 향상되었으며, 아마이드계와 금속염계 첨가제의 경우는 큰 영향이 없었다. 신율의 경우는 금속염계 첨가제의 경우 크게 향상되었으며, 나머지의 경우는 큰 영향이 없었다. 인열강도는 첨가제의 첨가에 따라 전반적으로 상승하였으며 금속염계 첨가제의 경우에서 확연히 상승하였으며 경도는 첨가제의 종류와 상관없이 유사한 값을 나타내었다. $100^{\circ}C$에서 24시간 열노화시킨 EPDM 배합물은 금속염계와 아마이드계 첨가제의 경우는 거의 변화가 없었으며 신율의 변화는 첨가제를 함유한 모든 EPDM 배합물이 10-20% 정도 감소하는 경향을 보였다.

• Journal of Magnetics
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• 제11권2호
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• pp.98-102
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• 2006

It was examined in this study that magnetic beads, which are assumed to be environmentally functional, could be effective in processing heavy metals that are water pollutants. For the purpose, magnetic beads containing carboxyl groups, which has strong binding force with heavy metals, are mixed with each Cd, Pb, Ni, Cu and Cr(III) solution, then stirred in pH 6. As a results of the process, it was proven that heavy metals bind quickly with magnetic beads through the reaction. In order to analyze heavy metal concentration, magnetic beads bind with heavy metal were collected by external magnetic force and dissolved in acid. The graphite furnace AAS was used to get heavy metal concentration melted in the acid solution. The results showed that heavy metal extractions by magnetic beads were influenced by the type and the concentration of a heavy metal, and over 90% of a heavy metal can be extracted in ppm level save for Cr(III). It was also examined in the study whether heavy metal extraction is influenced when other ions exist in each heavy metal solution. According to experiment, adding other heavy metals to a solution did have little influence on extracting an intended heavy metal. But in case salt or heavy metal chelate was added, Ni extraction changed sensitively although extracting other heavy metals were influenced only when the concentration of an added substance is high. In conclusion, it was shown that magnetic beads could be used to treat wastewater with relatively high heavy metal concentration.

• 한국환경과학회지
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• 제20권4호
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• pp.483-491
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• 2011

Harvesting of marshfire glasswort (Salicornia europaea) by local people has been increased recently since this plant was known for a well-being food. Even though some harvesting sites are facing high risk of environmental pollution, Salicornia europaea is still harvested on a large scale. Therefore, to investigate safety of Salicornia europaea as a food resource, salt marsh environment, potential harvestable biomass, element and heavy metal accumulations in Salicornia europaea has been studied in three salt marshes, west-coast of Korea. Salicornia europaea showed 150 - 230$g/m^2/yr$ harvestable biomass. Biomass and nitrogen contents of Salicornia europaea were closely related to soil nitrogen and carbon concentrations. Average Na, Zn, Fe, Cr accumulations in Salicornia europaea were 41479, 18, 297, 1.5 (mg/kg), indicating valuable trace element contents. However, average heavy metal accumulations such as As, Cd, Cu, Pb, Hg accumulations were 1.5, 7.1, 4.2, 1.5, 0.1 (mg/kg), which were even or higher than national standards (0.5, 0.5, 2, 2, 0.1) of salts. These results imply that harvesting and eating of Salicornia europaea in west-coast research sites would be harmful because the contents would be much higher if it is calculated as only considering salts and minerals. Therefore, harvesting of Salicornia europaea from some salt marsh in west-coast of Korea should be done cautiously.

• 한국환경보건학회지
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• 제14권1호
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• pp.73-86
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• 1988

In order to determine the content levels of trace metals in common salts, 64 bay salt samples were collected from three producing districts and 33 bay salt samples, 32 remade salt samples and 5 fine salt samples were collected from 7 major cities in Korea, from August to September 1987. These were analysed for content levels of Pb, Cd, Cu, Zn and Mn using Atomic Absorption Spectrophotometer. The results were as follows: 1. Lead contents in three type salts were N.D. - 1081.9 $\mu$g/kg and fourteen percent of the 114 samples exceeded the World Health Organization(WHO) criteria of 100$\mu$g/kg. Cadmium contents of samples were N.D.- 382C.5 $\mu$g/kg and five percent of the 114 samples were over the Spanish criteria of 500 $\mu$g/kg. Copper contents of samples were 8,9-214.9 $\mu$g/kg and there was not a sample over the World Health Organization(WHO) criteria of 500 $\mu$g/kg. Zinc contents ranged N.D. - 342.9 $\mu$g/kg and Manganese contents ranged N.D.- 8.31 mg/kg. 2. The comparison of heavy metal contents among the bay salts from three producing districts was significantly different in Pb, Cd and Cu contents. 3. The comparison of heavy metal contents between the bay salts and remade salts was not significantly different in Pb, Cd and Cu contents. 4. The contents of Pb, Cd, Zn and Mn in fine salts were much lower than those of bay salts and remade salts.