• Journal of Environmental Science International
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• v.19 no.11
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• pp.1385-1390
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• 2010

Repeated additions of untreated slurry to soil affected ecology and caused high levels of heavy metal in soil and ground water. The objective of this study was to evaluate heavy metal from hanwoo slurry with ferrous sulfate ($FeSO_4{\cdot}7H_2O$), aluminum sulfate [$Al_2(SO_4)_3{\cdot}14H_2O$, alum] and aluminum chloride ($AlCl_3{\cdot}6H_2O$) as a way to improve environmental management in hanwoo industry. The treatment rates, which were incorporated totally within the hanwoo slurry, were 1.0 g and 1.5 g of ferrous sulfate, alum and aluminum chloride/25 g of hanwoo slurry. The various rates of chemical additives significantly increased dry matter (9.98~13.94%) and decreased pH (3.48~6.52) compared with the controls. The use of chemical additives decreased Fe (11~29%), Al (7~12%), Zn (13~36%), and Cu (4~32%) contents, except for Fe in hanwoo slurry with ferrous sulfate and Al in hanwoo slurry with alum and aluminum chloride. In addition, the reduction in heavy metal should be associated with reduction in pH. In conclusion, the results of this study suggest that alum and aluminum chloride additives at rate of 1.5 g were cost-effective management practice that significantly reduces heavy metal from hanwoo slurry, while it may be improved environmental management.

• Journal of Ginseng Research
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• v.30 no.3
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• pp.100-105
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• 2006

Liver and kidney are specific organs which play an active role in biotransformation and detoxification mechanisms. Ant adverse effect of chemicals or heavy metal can cause the delay or fade in these mechanisms. Present study was designed to find out the protective effect of Panax ginseng extract on renal functions altered by mercuric chloride (heavy metal) in albino rat. Fifty albino rats were divided into 10 groups. Five groups for acute study and five groups for sud-acute study viz. control group (Tween 20 and distilled water), mercuric chloride treated group (0.926 mg/kg body wt. for acute and 0.044 mg/kg body wt. for sub-acute group after calculated $LD_{50}$ (9.26 mg/kg body wt.) by probit analysis (Finney, 1971), Panax ginseng extract treated group (10 mg/kg body wt. for acute and sub-acute sets), mercuric chloride treated followed by Panax ginseng extract and Panax ginseng extract followed by mercuric chloride group. All doses were given orally by gavage tube. The result revealed that the serum urea and creatinine significantly increased in mercuric chloride treated group, while significantly decreased (p<0.01) in Panax ginseng extract group after acute and sub-acute treatment. The biochemical estimation is also confirmed by nephropathological aspect. However, the Panax ginseng extract treated followed by mercuric chloride group is more prominent than the mercuric chloride treated followed by Panax ginseng extract group. It can be concluded that Panax ginseng extract had a protective nature on renal functions against mercuric chloride toxicity in albino rats.

• Proceedings of the Korean Geotechical Society Conference
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• 2003.03a
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• pp.593-596
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• 2003

The special amendment agent used in this study is mainly composed of inorganic metal salts such as sodium chloride, magnesium chloride, potassium chloride, calcium chloride, thus is friendly to the environment, and has a function of soil-cement-agent solidification. In this study, a series of laboratory and field experiments including unconfined compressive strength, permeability, pH test, constituent analysis, leaching test were carried out to analyse engineering and environmental characteristics of solidified sludge. The results of this research showed that the solidified sludge could be efficiently used in covering, filling, and planting materials.

• Journal of Microbiology and Biotechnology
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• v.25 no.5
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• pp.672-680
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• 2015

As a global regulatory gene in Streptomyces, afsR can activate the biosynthesis of many secondary metabolites. The effect of afsR on the biosynthesis of a phenazine metabolite, lomofungin, was studied in Streptomyces lomondensis S015. There was a 2.5-fold increase of lomofungin production in the afsR-overexpressing strain of S. lomondensis S015 N1 compared with the wild-type strain. Meanwhile, the transcription levels of afsR and two important genes involved in the biosynthesis of lomofungin (i.e., phzC and phzE) were significantly upregulated in S. lomondensis S015 N1. The optimization of metal chlorides was investigated to further increase the production of lomofungin in the afsR-overexpressing strain. The addition of different metal chlorides to S. lomondensis S015 N1 cultivations showed that CaCl₂, FeCl₂, and MnCl₂ led to an increase in lomofungin biosynthesis. The optimum concentrations of these metal chlorides were obtained using response surface methodology. CaCl₂ (0.04 mM), FeCl₂ (0.33 mM), and MnCl₂ (0.38 mM) gave a maximum lomofungin production titer of 318.0 ± 10.7 mg/l, which was a 4.1-fold increase compared with that of S. lomondensis S015 N1 without the addition of a metal chloride. This work demonstrates that the biosynthesis of phenazine metabolites can be induced by afsR. The results also indicate that metal chlorides addition might be a simple and useful strategy for improving the production of other phenazine metabolites in Streptomyces.

• Journal of the Korean institute of surface engineering
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• v.29 no.5
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• pp.478-481
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• 1996

Disproportionation reaction is very important and interesting reaction to be applied to such surface treatment as metal, alloy, compound coating, a surface etching and so on. In gaseous system, the reaction of Al chloride is applied to Al and Al alloy coating, and the similar reaction of Ti chloride is also used for Ti, Ti alloy and Ti compound coating. As for aqueous system, this reaction is utilized to such metal coat as Sn etc. and metal etching such as Cu, Fe and so on. Also in molten salts system, this reaction has many application for surface treatment like metal, alloy and compound coatings for corrosion, wear, heat resistance and so forth. For instance, carbide film, nitride film, boride film, alloy film, quite new different film from the components of substrate material are coated in single and multiple component film system by the disproportionation reaction.

• Applied Chemistry for Engineering
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• v.34 no.4
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• pp.450-454
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• 2023

Chloride ions in the alloy powder used as flux in Flux Cored Arc Welding (FCAW) can cause pores on the bead surface of the welding metal to cause defects, or chloride remaining in the alloy powder can cause corrosion of the metal. Combustion-ion chromatography is mainly used to quantify the chloride ions in alloy powder, but there is a limitation in that the equipment is expensive and requires a high degree of expertise. Therefore, this study aims to find an easy and accurate quantification method in the field by comparing combustion-ion chromatography (C-IC), which is mainly used for chloride ion quantification of alloy powder, X-ray fluorescence analysis (XRF), and potentiometric titration. In this article, magnesium-aluminum alloy powder is applied to the quantification of chloride ions because it is most commonly used as flux. This study confirmed that potentiometric titration can be applied to the quantification of chloride ions in the alloy powder in the industry field.

• Journal of Environmental Health Sciences
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• v.23 no.2
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• pp.12-23
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• 1997

The biosynthesis of galactolipid, galactose and the fatty acid composition in E. cdi and B. subtills treated with potassium dichromate(PD, 500 ppm, 500 ppm), potassium chromate(PC, 500 ppm, 500 ppm), cobalt chloride(CC, 100 ppm, 10 ppm) and methylmercuric chloride(MC, 100 ppm, 10 ppm) during the culture were analyzed to compare with the control. The growth rate of cells, the contents of monogalactosyldiglyceride(MGDG), digalactosyldiglyceride(DGDG) and total lipid in the metal compound treatments were lower as compared with the control. And too, the contents of galactose utilized for the biosynthesis of galactolipids in these strains in the various metal compounds treatments were inhibited. The fatty acids used for the MGDG and DGDG formation in E. coli and B. subtills treated with each metal compounds during the culture were showed to the variant compositional change.

• Journal of Korean Society of Water and Wastewater
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• v.18 no.4
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• pp.493-499
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• 2004

Rejection characteristics of heavy metals by nanofiltration membranes were investigated. Nanofiltration membranes rejected heavy metals much better than chloride, sulfate and TOC, of which concentration in synthetic wastewater was higher than that of heavy metals. To consider rejection characteristics of various metals by nanofiltration membranes, separation coefficient, which is the ratio of the metal permeation rate to the chloride ion or TOC permeation rate, was introduced. In spite of different materials and different nominal salt rejection of nanofiltration membrane used, the separation coefficients of metals were nearly the same. In particular, the separation coefficient of arsenic against chloride ion and TOC was larger than any other separation coefficient of heavy metals. These phenomena were observed in the relationship between the molar conductivity and the separation coefficient for heavy metals.

• Restorative Dentistry and Endodontics
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• v.23 no.1
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• pp.502-514
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• 1998

The purpose of this study is to observe the corrosion characteristcs of four dental amalgams(CAULK FINE CUT, CAULK SPHERICAL, DISPERSALLOY, TYTIN) and to determine a function of chloride concentration through the anodic polarization curve obtained by using a potentiostat. After each amalgam alloy and Hg being triturated, the triturated mass was inserted into the cylinderical metal mold, and condensed by hydrolic pressure. Each specimen was removed from the metal mold. 24 hours after condensation, specimens were polished with the emery paper and stored at room temperature for 6 months. The anodic polarization curves were employed to compare the corrosion behaviours of the amalgam m KCl and KCl-NaCl solution, which had chlonde concentration of 0.4 g/l, 0.8 g/l, 1.2 gil, and 1.6 gil at $37^{\circ}C$ with 3-electrode potentiostat. After the immersion of specimen in electrolyte for 1 hour, the potential scan was begun. The potential scan range was - 1500mV ~+800mV(vs. S.C.E.) in the working electrode and the scan rate was 50mV/sec. The results were as follows, 1. The corrosion potential. the potential of anodic current peak, and transpassive potential in the solution of high chloride concentration shifted to more cathodic direction than those in the solution of low concentration, and the current density in the solution of high chloride concentration was higher than that in the solution of low concentration. 2. The corrosion potential, the potential of anodic current peak, and transpassive potential for CAULK FINE CUT amalgam were the most cathodic among the others, and the current density were the highest among the others. 3. In the solution of low chloride concentration, the corrosion potential, the potential of anodic current peak, and transpassive potential for DISPERSALLOY were the most anodic among the others, however in the solution of high chloride concentration, those for TYTIN were the most anodic among the others. 4. The anodic polarization curve for CAULK SPHERICAL was similar to that for high copper amalgams.

• Bulletin of the Korean Chemical Society
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• v.33 no.2
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• pp.625-628
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• 2012

We investigated the interaction between polyynes (linear carbon chains) and various metal nanoparticles (Ag, Au, and Cu) to provide insight into the optical properties of metal-polyynes systems prepared by different experimental techniques. Polyynes were produced by laser ablation in deionized water, metal nanoparticles solutions, and copper chloride solution. Metal nanoparticles complexes with polyynes were analyzed by Raman, surface-enhanced Raman scattering, and UV-vis spectroscopy.