• Resources Recycling
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• v.9 no.3
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• pp.3-12
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• 2000

A Study on the cementation for the recovery of Cu, Ni and Co with Mn metallic powders in leaching solution from the manganese nodule that have removed Fe ions was studied. The results showed that the recovery efficiencies of metal ions with Mn powders increased when the temperature, pH and the concentration of chloride ions were increased in mixed solution. And the recovery efficiencies of Cu was 98% and not changed with the addition amounts of Mn powders but, in case of Co and Ni, the recovery efficiencies were increased with the addition amounts. The particle size of precipitate was about $5\mu\textrm{m}$. From the results of experiment we proposed the two-step cementation process for the recovery of Cu, Ni and Co with Mn powders.

• Journal of Ocean Engineering and Technology
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• v.27 no.3
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• pp.79-84
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• 2013

The seawater pipes in the engine rooms of ships are surrounded by severely corrosive environments caused by fast flowing seawater containing chloride ions, high conductivity, etc. Therefore, it has been reported that seawater leakage often occurs at a seawater pipe because of local corrosion. In addition, the leakage area is usually welded using shielded metal arc welding with various electrodes. In this study, when seawater pipes were welded with four types of electrodes(E4311, E4301, E4313, and E4316), the difference between the corrosion resistance values in their welding zones was investigated using an electrochemical method. Although the corrosion potential of a weld metal zone welded with the E4316 electrode showed the lowest value compared to the other electrodes, its corrosion resistance exhibited the best value compared to the other electrodes. In addition, a heat affected zone welded with the E4316 electrode also appeared to have the best corrosion resistance among the electrodes. Furthermore, the corrosion resistance of the weld metal zone and heat affected zone exhibited relatively better properties than that of the base metal zone in all of the cases welded with the four types of electrodes. Furthermore, the hardness values of all the weld metal zones were higher than the base metal zone.

• Journal of Korea Foundry Society
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• v.20 no.1
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• pp.38-45
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• 2000

The remelting for recycling or thin aluminum scrap, such as aluminum chip generally involves melting of these pieces submerged in molten salt flux. In this study, the effects of salt flux compositions and alloying elements on the aluminum dropletscoalescence and oxide film removal were studied in 99.8%Al, Al-1.01%Cu, Al-1.03%Si, and Al-1.38%Mg alloys as a function of holding time at $740^{\circ}C$ Salt fluxes based on NaCl-KCl(1:1) with addition of 5wt.% fluorides(NaF, $Na_3AlF_6$, $CaF_2$) or 5 wt.% chloride($MgCl_2$, $AlCl_3$) were used. The experimental results show that NaCl-KCl(1:1) with addition of 5 wt.% fluorides exhibits better coalescence ability than that with chlorides. The oxide film is not removed by NaCl-KCl(1:1) with addition of 5 wt.%chlorides, while it is removed by NaCl-KCl(1:1) with addition of 5 wt.% fluorides. The aluminum droplets coalescence and oxide film removal by salt fluxes are related to interfacial tension tension between metal and salt flux.

• Journal of the Korean institute of surface engineering
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• v.48 no.3
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• pp.73-81
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• 2015

Chloride plating solution was fabricated by dissolving metal Ni powders in solution with HCl and deionized water. Effects of deposition conditions on the properties of Ni films electrodeposited from chloride baths were studied. Current efficiency of Ni films electrodeposited from the baths containing saccharin was decreased with increasing the current density. Residual stress of Ni thin films ware measured to be about 230 ~ 435 MPa in the range of current density of $10{\sim}25mA/cm^2$. Cathode current efficiency in baths without saccharin was initially increased with increasing pH, while it was decreased with increasing pH further. Cathode current efficiency in baths with saccharin (except at pH 2) exhibited less 10 ~ 20% than that in baths without saccharin. Residual stress of Ni films electrodeposited from baths without saccharin was measured to be 388 ~ 473 MPa in the range of pH 2 ~ pH 5 and then was increased to 551 MPa at pH 6. On the other hand, residual stress of Ni films electrodeposited from baths with saccharin was increased with increasing pH. Surface morphology was strongly affected by the change of current density, but slightly by solution pH and addition of saccharin.

• Journal of the Korean Electrochemical Society
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• v.19 no.3
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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.

• Carbon letters
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• v.26
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• pp.18-24
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• 2018

Pollution of chloride ion-reinforced concrete can trigger active corrosion processes that reduce the useful life of structures. Multifunctional materials used as a counter-electrode by electrochemical techniques have been used to rehabilitate contaminated concrete. Cement-based pastes added to carbonaceous material, fibers or dust, have been used as an anode in the non-destructive Electrochemical Chloride Extraction (ECE) technique. We studied the performance of the addition of Carbon Fiber (CF) in a cement-graphite powder base paste used as an anode in ECE of concretes contaminated with chlorides from the preparation of the mixture. The experimental parameters were: 2.3% of free chlorides, 21 days of ECE application, a Carbon Fiber Volume Fraction (CFVF) of 0.1, 0.3, 0.6, 0.9%, a lithium borate alkaline electrolyte, a current density of $4.0A/m^2$ and a cement/graphite ratio of 1.0 for the paste. The efficiency of the ECE in the traditional technique using metal mesh as an anode was 77.6% and for CFVF of 0.9% it was 90.4%, with a tendency to increase to higher percentages of the CFVF in the conductive cement-graphite paste, keeping the pH stable and achieving a homogeneous ECE in the mass of the concrete contaminated with chlorides.

• Molecular & Cellular Toxicology
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• v.2 no.1
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• pp.21-28
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• 2006

Gadolinium chloride ($GdCl_{3}$) was known to block Kupffer cells and generally its toxicity study based on blocking these cells. Therefore, $GdCl_{3}$ frequently used to study toxic mechanisms of hepatotoxicants inducing injury through Kupffer cells. We also tried to investigate the effect of $GdCl_{3}\;on\;CCl_{4}$ toxicity, typical hepatotoxicants. Administration of $GdCl_{3}$ to mice significantly suppressed AST (asparatate amino transferase), ALT (alanine amino transferase) levels which were increased by $CCl_{4}$ treatment. However, $GdCl_{3}$ didn't inhibit the phagocytotic activity of Kupffer cells. Malondialdehyde (MDA) is a good indicator of the degree of lipid peroxidation. In this study, MDA increased by $GdCl_{3}$ administration not by $CCl_{4}$. To understand the toxicity of $GdCl_{3}$, we analyzed global gene expression profile of mice liver after acute $GdCl_{3}$ injection. Four hundred fifty two genes were differentially expressed with more than 2-fold in at least one time point among 3 hr, 6 hr, and 24 hr. Several genes involved in fibrogenesis regulation. Several types of pro-collagens (Col1a2, Col5a2, Col6a3, and Col13a1) and tissue inhibitor of metal-loproteinase1 (TIMP1) were up regulated during all the time points. Genes related to growth factors, chemokines, and oxidative stress, which were known to control fibrogenesis, were significantly changed. In addition, $GdCl_{3}$ induced abnormal regulation between lipid synthesis and degradation related genes. These data will provide the information about influence of $GdCl_{3}$ to hepatotoxicity.

• Bulletin of the Korean Chemical Society
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• v.35 no.7
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• pp.2109-2113
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• 2014

Solvent extraction of Fe(III) from chloride solution by using a mixture of D2EHPA (Di-(2-ethylhexyl)-phosphoric acid) and TBP (Tri-butyl phosphate) and the reductive stripping of Fe(III) from the loaded organic were investigated. Quantitative extraction of Fe(III) from the solution (Fe concentration = 90 g/L) was accomplished in two cross-current extraction stages by using the mixture of D2EHPA and TBP. In order to facilitate the stripping efficiency, a reductive stripping method was employed by using $H_2SO_3$ or $Na_2SO_3$ as a reducing agent. The addition of $H_2SO_4$ into reducing agents led to improvement in the stripping efficiency while high concentration acid would suppress it. Both of the mixtures of $H_2SO_4+H_2SO_3$ and $H_2SO_4+Na_2SO_3$ showed good efficiency for the stripping of Fe(III), while the latter was recommended as the stripping solution based on the economics and experimental condition.

• Journal of Pharmaceutical Investigation
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• v.29 no.3
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• pp.171-177
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• 1999

Lidocaine(2-Diethylaminoaceto-2', 6'-xylidide) was transdennally delivered by iontophoresis and the effect of enhancer on the delivery of lidocaine was studied. We delivered lidocaine through the skin of hairless mouse using diffusion cell and investigated the effect of the amount of cation salts such as sodium chloride, calcium acetate, zinc acetate and aluminum acetate on the drug delivery. The amounts of transported drugs and adsorbed metal ions were measured by HPLC(High Perfonnance Liquid Chromatography) and AAS(Atomic Absorption Spectrophotometry), respectively. The addition of zinc acetate and aluminum acetate greatly enhanced the delivery of lidocaine. The detection of two metal ions by AAS seemed to support the idea that the astringency effect of these ions were the main reason for the enhancement of transdermal delivery.

• Nutrition Research and Practice
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• v.3 no.1
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• pp.15-22
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• 2009

This study was performed to investigate the effect of chlorella on cadmium (Cd) toxicity in Cd-administered rats. Sixty male Sprague-Dawley rats (14 week-old) were blocked into 6 groups. Cadmium chloride was given at levels of 0 or 325 mg (Cd: 0, 160 ppm), and chlorella powder at levels of 0, 3 and 5%. Cadmium was accumulated in blood and tissues (liver, kidney and small intestine) in the Cd-exposed groups, while the accumulation of Cd was decreased in the Cd-exposed chlorella groups. Fecal and urinary Cd excretions were remarkably increased in Cd-exposed chlorella groups. Thus, cadmium retention ratio and absorption rate were decreased in the Cd exposed chlorella groups. Urinary and serum creatinine, and creatinine clearance were not changed in experimental animals. In addition, metallothionein (MT) synthesis in tissues was increased by Cd administration. The Cd-exposed chlorella groups indicated lower MT concentration compared to the Cd-exposed groups. Moreover, glomerular filtration rate (GFR) was not changed by dietary chI orella and Cd administration. According to the results above, this study could suggest that Cd toxicity can be alleviated by increasing Cd excretion through feces. Therefore, when exposed to Cd, chlorella is an appropriate source which counteracts heavy metal poisoning, to decrease the damage of tissues by decreasing cadmium absorption.