• Journal of Korean Society of Environmental Engineers
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• v.22 no.3
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• pp.441-451
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• 2000

Sludge produced from water treatment plants contains plenty of aluminum due to addition of coagulants, polyaluminum chloride(PACI) which has been widely used in most of water treatment plants. however. the whole of PACI is imported from other countries. In this research. the effective methods for recycling PACI from sludge of water treatment plants were developed and evaluated. Aluminum chloride hexahydrate($AlCl_3{\cdot}6H_2O$) was obtained by sparging HCl gas aluminum extracted from sludge using hydrochloric acid (HCI). This aluminum chloride hexahydrate was solidified by decomposition at $180^{\circ}C$. and dissolved in water to produce PACI. The optimum extraction rate was obtained at the condition of 10 minutes of reaction time. $105^{\circ}C$ of reaction temperature. 27.65%(W/W) of HCI concentration. The KS experiment proved that manufactured aluminum chloride hexahydrate was 98.7% degree and the recycled PACI coagulants agreed with the KS standard. The optimum temperature of decomposition was $180^{\circ}C$ and the basicity of the PACI was decided upon the extent of decomposition The compared experiments between purchased coagulant and manufactured coagulant presented that both coagulants had same performance for turbidity, DOC, $UV_{254}$ absorbance. and chlorophyll-a.

• Journal of Environmental Health Sciences
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• v.23 no.4
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• pp.26-32
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• 1997

To evaluate the cytogenetic toxicity, of cadmium and the reducing effect of selenium or zinc on cadmium toxicity, the induction of SCEs in cultured human lymphocytes by the concentraion of 0.5 $\mu$M to 16.0 $\mu$M of cadmium chloride and those of cadmium chloride combined with sodium selenite or zinc chloride 1.2 $\mu$M, respectively was investigated. The induction of SCEs by cadmium chloride in the range of 0.5 $\mu$M to 16.0 $\mu$M increased in a dose-dependent manner. A notable increase in SCEs by sodium selenite as well as zinc chloride was also observed. However, the frequency of SCEs by cadmium chloride was inhibited by the simultaneous addition of sodium selenite and zinc chloride 1.2 $\mu$M, respectively. The mitotic index significantly decreased in higher concentration of cadmium chloride but not was significantly different in any concentration of cadmium chloride with the simultaneous addition of sodium selenite or zinc chloride. The results showed that the decreased additive SCE effect was observed when induced by the combined treatment which could suggest that sodium selenite and zinc chloride have a protective effect on cadmium chloride.

• Journal of the Korean Applied Science and Technology
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• v.12 no.1
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• pp.81-86
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• 1995

Some weight loss accelerating agents, dodecyltrimethylammonium chloride(DTAC), dodecyltrimethylammonium bromide(DTAB), dodecyldimethylammonium chloride(DDBAC), polyoxyethylene(2) dodecylbenzylammonium chloride(PDBAC), and 1-(2-hydroxyethyl)-1-benzyl-2-undecylimidazolinium chloride(AEUIC), were synthesized. As a result of weight loss treatment of the weight loss accelerating agents with NaOH to PET fiber, the increase of weight loss was the order of PDBAC > DDBAC > DTAC > DTAB > AEUIC. Among the weight loss accelerating agents, AEUIC hardly showed weight loss effect, and it was separated into two layer in the NaOH solution at the treatment concentration above 6g/L, but POBAC showed good weight loss effect of 21% that approach almost to a theoretical weight loss, 21.6%, at the concentration above 8g/L.

• Korean Journal of Environmental Biology
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• v.28 no.2
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• pp.101-107
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• 2010

Metal ions are essential to life. However, some metals such as mercury are harmful, even when present at trace amounts. Toxicity of mercury arises mainly from its oxidizing properties. Ionizing radiation (IR) is an active tool for destruction of cancer cells and diagnosis of diseases, etc. IR induces DNA double strand breaks in the nucleus, In addition, it causes lipid peroxidation, ceramide generation, and protein oxidation in the membrane, cytoplasm and nucleus. Yeasts have been a commonly used material in biological research. In yeasts, the physiological response to changing environmental conditions is controlled by the cell types. Growth rate, mutation and environmental conditions affect cell size and shape distributions. In this work, the effect of IR and mercury chloride (II) on the morphology of yeast cells were investigated. Saccharomyces cerevisiae cells were treated with IR, mercury chloride (II) and IR combined with mercury chloride (II). Non-treated cells were used as a control group. Morphological changes were observed by a scanning electron microscope (SEM). The half-lethal condition from the previous experimental results was used to the IR combined with mercury. Yeast cells were exposed to 400 and 800 Gy at dose rates of 400Gy $hr^{-1}$ or 800 Gy $hr^{-1}$, respectively. Yeast cells were treated with 0.05 to 0.15 mM mercury chloride (II). Oxidative stress can damage cellular membranes through a lipidic peroxidation. This effect was detected in this work, after treatment of IR and mercury chloride (II). The cell morphology was modified more at high doses of IR and high concentrations of mercury chloride(II). IR and mercury chloride (II) were of the oxidative stress. Cell morphology was modified differently according to the way of oxidative stress treatment. Moreover, morphological changes in the cell membrane were more observable in the frequently stress treated cells than the temporarily stress treated cells.

• 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 the Korean Recycled Construction Resources Institute
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• v.10 no.4
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• pp.553-557
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• 2022

The present study evaluate the chloride extracion under electrochemical chloride extraction method. Chloride was penetrated into the concrete from external reservoir using a 4M NaCl solution, and an electrochemical chloride extraction method was applied after the curing period of 1 year. The current density was constantly kept 1000 mA/m² for coulostatic application with the variation in potential difference. The duration of the ECE treatment was 2, 4, 8 weeks, respectively. The residual chloride concentration at all depths decreased, and the chloride concentration decreased as the application period increased. After the application period of 8 weeks, 62.9 to 77.6 % of chloride extracted in the total chloride profile, and 77.7 to 99.5 % of chloride extracted in the free chloride profile. In particular, the concentration of free chloride at a depth of 7 mm or more from the concrete surface was 0.01 % or less by cement. In addition, it was confirmed that the bound chloride could be extracted by the electrochemical chloride extraction.

• Journal of Korean Society of Forest Science
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• v.104 no.1
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• pp.84-89
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• 2015

The effects of dip treatments of chemicals (ascorbic acid, citric acid, calcium chloride: 1% solution) and physicals (vacuum packing, $50^{\circ}C$ distilled water) on the browning and quality of 'Daebo' peeled chestnut were studied. During the storage, the surface color of the samples showed higher ${\Delta}E$ values and lower L values than that of the initial sample. The color with the normal packing treatment hardly changed, unlike in the chemical and physical treatments. The calcium chloride treatment showed less color change than other treatments. The marketable quality was maintained for 10 days with the normal packing and for 35 days with the chemical and physical treatments. Thus, the chemical and physical treatments, especially with vacuum packing after 1% calcium chloride treatment, extended the shelf-life of the 'Daebo' peeled chestnut by inhibiting the browning.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.8
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• pp.1233-1238
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• 2003

The growth inhibitory effects of chloride salts and organic acid salts against six food-borne microorganisms (Bacillus cereus ATCC 11778, Escherichia coli O157:H7 ATCC 43894, Listeria monocytogenes ATCC 19111, Salmonella Typhimurium ATCC 14028, Staphylococcus aureus ATCC 25923, Vibrio parahaemolyticus ATCC 17802) were determined using Bioscreen C in broth medium. The growth inhibitory concentrations of sodium chloride and potassium chloride on B. cereus were 7 and 9%, respectively. E. coli O157:H7 and S. aureus were inhibited by treatment of 3% calcium chloride. Magnesium chloride showed growth inhibitory effect on B. cereus, S. Typhimurium, and S. aureus at 5%. The order of growth inhibition effects by organic acid salts was calcium propionate>calcium acetate>calcium lactate. Calcium chloride (3%) with 0.01% lactic acid showed strong inhibition on the growth of S. Typhimurium and exhibited stronger growth inhibition than calcium chloride alone (5%). We concluded that calcium chloride and calcium propionate had strong growth inhibitory activities and that calcium chloride and sodium chloride in combination with lactic acid had stronger inhibitory activities than that of chloride salts alone.

• Journal of Ginseng Research
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• v.16 no.1
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• pp.24-30
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• 1992

Extracts of Panax ginseng root significantly induced tolerance of Fusarium oxysporum to heavy metal, mecury, as the fungal mycelial growth was less inhibited by mercury chloride on potato dextrose medium(PDA) amended with ginseng root than on the PDA with no ginseng amendment. The most favorable concentration of ginseng root powder in detoxification of mercury chloride was 1%. The induced tolerance of F. oxysporum to mercury chloride appeared to be rather due to absorption of ginseng components, and was not related to stimulation of mycelial growth of the fungus per so by ginseng treatment. Ginseng components responsible for inducing tolerance of the fungus to mercury were involved in the water fraction of the ginseng root extract, although the water fraction had no effect on enhancement of the mycelial growth on the medium without mercury chloride. The hexane fraction of ginseng root extract, by which the mycelial growth was stimulated, was not related to the inducement of the tolerance to mercury chloride. However, more tolerance to mercury chloride was noted in PDA with both the water and hexane fractions combined than with either of the two fractions. Six-year-old ginseng roots were more effective in detoxification of mercury chloride than 4-year-old ginsng roots, and American ginseng (P quinquifolium) had no or little effect on inducing tolerance of the fungus to mercury chloride. This method may be used to screen other natural materials for test in the detoxification of mercury chloride.

• Journal of the Korean institute of surface engineering
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• v.40 no.1
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• pp.44-56
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• 2007

Excavated archaeological iron artifacts are usually conducted the conservation treatment for removal of chloride ions in the corrosion products. However, some iron artifacts are corroded again even after the conservation treatment due to unremoved chloride ions. Therefore, it is important to prevent desalinized artifacts from the occurrence of corrosion after the treatment. In this paper, we investigated the characteristics of corrosion products on salinized iron artifacts and evaluated the variety of desalination methods such as autoclave, intensive washing and NaOH. It was also found that ${\beta}-FeOOH$ (Akaganeite) played an important role on the occurrence of corrosion and the treatment for removal of chloride ions. The extents of desalination were compared between the desalination methods. Results showed that the autoclave method represented the highest efficiency for desalination while the intensive washing method was the lowest.