• 한국환경보건학회지
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• 제23권4호
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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 Oral Medicine and Pain
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• 제23권4호
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• pp.343-352
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• 1998

This experiment was performed to investigate effects of zinc containing solution on the major normal flora Staphylococccus aureus, Streptococus mutans and Candida albicans and to observe the variation according to anionic change and concentration difference. Zinc chloride, zinc iodide and zinc acetate solution were added to werially diluted broth culture so that each final concentration might be 0.25%, 0.5%. 1%. After that, 100ul of each aliquot was spreaded on each selective media plate( Mannitol Salts Agar plate for Staphylococcus aureus, Mitis Salivarius Agar plate for Streptococcus mutans and Sabouraud Destrose Agar plate for Candida albicans). The % killing was calculated bu CFU count after incubation under the appropriate condition. 1. zinc iodide, zinc chloride, and zinc acetate solutions showed inhibitory effects on Staphylococcus aureus, Streptococcus mutans and Candida albicans. 2. The inhibitory effects on Staphylococcus aureus were ranked in order of ainc iodide, zinc chloride and zinc actate. 3. The inhibitory effects on Streptococcus mutans were ranked in orfer of zinc iodide, zinc chloride and zinc acetate. 4. the inhibitory effects on Candida albicans showed no difference among zinc iodide, zinc chloride and zinc acetate. 5. The inhibitory effects of zinc chloride and zinc acetate on Staphylococcus aureus and Streptococcus mutnas showed increasing pattern as the concentration increase. But the inhibitory effects of zinc iodide on Staphylococcus aureus and Streptococcus mutans showed no apparent difference according to concentrations and it was the case with the inhibitory effects of zinc iodide, zinc chloride and zinc acetate on Candida albicans.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1994년도 가을 학술발표회 논문집
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• pp.87-92
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• 1994

The main objective of this study is to determine the critical chloride ion concentrations in the pore solutions causing depassivation of steel reinforcement in concrete made with cements of different $C_3A$ contents. Cement pastes with water-ratio of 0.5 were prepared using four cements with $C_3A$ contents of 0.46, 5.97, 9.14, and 9.65 percent. The pastes were allowed to hydrate in sealed containers for 28days and then objected to pore solution expression. The expressed pore fluids were analyzed for chloride and hydroxyl ion concentrations. It was found that the free cholride concentration in the pore solution decreases significantly with an increase in the $C_3A$ content of the cement. With increasing level of chloride addition, although the alsolute amount of bound chloride increase, the ratio of bound to total chlorides decreases.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2018년도 춘계 학술논문 발표대회
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• pp.27-28
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• 2018

Deterioration of reinforced concrete structures due to salt corrosion is a phenomenon that can be easily seen, and the main reason for deterioration is chloride ion. Therefore, researches are actively conducted to control chlorine ion penetration worldwide. The purpose of this study is to evaluate the chloride ion fixation capacity of Portland cement paste containing Hydrotalcite. For this purpose, cement paste containing 0%, 2.5%, and 5% of Hydrotalcite was sealed and cured for 28 days, and the cured cement paste was crushed. Chloride ion solution was prepared at a concentration of 0.5M using NaCl, and the powdered cement paste was reacted for a specific time in aqueous chloride ion solution. After the reaction, the concentration of the chloride ion aqueous solution was measured using a silver nitrate potentiometric titrator, and the reacted cement paste was analyzed using XRD and FT-IR.

• Computers and Concrete
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• 제3권6호
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• pp.401-422
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• 2006

A multi-species model based on the Nernst-Planck equation has been developed by using a finite volume method. The model makes it possible to simulate transport due to an electrical field or by diffusion and to predict chloride penetration through water saturated concrete. The model is used in this paper to assess and analyse chloride diffusion coefficients and chloride binding isotherms. The experimental assessment of the effective chloride diffusion coefficient consists in measuring the chloride penetration depth by using a colorimetric method. The effective diffusion coefficient determined numerically allows to correctly reproduce the chloride penetration depth measured experimentally. Then, a new approach for the determination of chloride binding, based on non-steady state diffusion tests, is proposed. The binding isotherm is identified by a numerical inverse method from a single experimental total chloride concentration profile obtained at a given exposure time and from Freundlich's formula. In order to determine the initial pore solution composition (required as initial conditions for the model), the method of Taylor that describes the release of alkalis from cement and alkali sorption by the hydration products is used here. Finally, with these input data, prediction of total and water-soluble chloride concentration profiles has been performed. The method is validated by comparing the results of numerical simulations to experimental results obtained on various types of concretes and under different exposure conditions.

• 대한수의학회지
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• 제34권1호
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• pp.25-36
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• 1994

The inward tail current after a short depolarizing pulse has been known as Na-Ca exchange current activated by intracellular calcium which forms late plateau of the action potential in rabbit atrial myocytes. Chloride conductance which is also dependent upon calcium concentration has been reported as a possible tail current in many other excitable tissues. Thus, in order to investigate the exsitance of the calcium activated chloride current and its contribution to tail current, whole cell voltage clamp measurement has been made in single atrial cells of the rabbit. The current was recorded during repolarization following a brief 2 ms depolarizing pulse to +40mV from a holding potential of -70mV. When voltage-sensitive transient outward current was blocked by 2 mM 4-aminopyridine or replacement potassium with cesium, the tail current were abolished by ryanodine$(1{\mu}M)$ or diltiazem$(10{\mu}M)$ and turned out to be calcium dependent. The magnitudes of the tail currents were increased when intracellular chloride concentration was increased to 131 mM from 21 mM. The current was decreased by extracellular sodium reduction when intracellular chloride concentration was low(21 mM), but it was little affected by extracellular sodium reduction when intracellual chloride concentration was high(131 mM). The current-voltage relationship of the difference current before and after extracellular sodium reduction, shows an exponential voltage dependence with the largest magnitude of the current occurring at negative potentials, with is similar to current-voltage relationship at negative potentials, which is similar to current-voltage relationship of Na-Ca exchange current. The current was also decreased by $10{\mu}M$ niflumic acid and 1 mM bumetanide, which is well known anion channel blockers. The reversal potentials shifted according to changes in chloride concentration. The current-voltage relationships of the niflumic acid-sensitive currents in high and low concentration of chloride were well fitted to those predicted as chloride current. From the above results, it is concluded that calcium activated chloride component exists in the tail current with Na-Ca exchange current and it shows the reversal of tail current. Therefore it is thought that in the physiologic condition it leads to rapid end of action potential which inhibits calcium influx and it contributes to maintain the low intracellular calcium concentration with Na-Ca exchange mechanism.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 추계 학술발표회 논문집
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• pp.573-576
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• 2006

To predict service life of concrete structures exposed to chloride attack, surface chloride concentration, diffusion coefficient of chloride ion, and chloride corrosion threshold value in concrete, are used as important factors. of these, as the diffusion coefficient of chloride ion for concrete is strongly influenced by concrete quality and environmental conditions of structures and may significantly change the service life of structures, it is considered as the most important factor for service life prediction. The qualitative factors affecting the penetration and diffusion of chloride ion into concrete are water-binder(W/B) ratio, age, cement type and constituents, chloride ion concentration of given environment, wet and dry conditions, etc. In this paper the influence of cement type on the diffusion characteristics of chloride ion in concrete was investigated through the chloride ion diffusion test. For this purpose, the diffusion characteristics in concrete with cement type such as ordinary portland cement(OPC), binary blended cement(BBC), and ternary blended cement(TBC) were estimated for the concrete with W/B ratios of 32% and 38%, respectively. It was observed from the test that the difussion characteristics of BBC containing OPC and ground granulated blast-furnace slag was found to be most excellent of the cement type used in this study.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 추계 학술발표회 논문집
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• pp.725-728
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• 2006

This research investigates the characteristics of chloride fixation in non-sintering cement(NSC) matrix. NSC was manufactured by adding phosphogypsum and slack lime to granulated blast furnace slag as sulfate and alkali activators. As a result, the concentration of chloride ion in pore solution of NSC-solidified matrix is more low than that of OPC-solidified matrix containing the same chloride content in cement paste. Also, the concentration of chloride ion in pore solution of NSC-solidified matrix is similar with that of BSC-solidified matrix containing the same chloride content in cement paste.

• Corrosion Science and Technology
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• 제21권6호
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• pp.454-465
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• 2022

The objective of this study was to determine effects of temperatures and pH of sodium chloride solution with MgCl₂ ions on corrosion resistance of duplex stainless-steel X2CrNiMoN22-5-3 (DSS) and Ti 6Al 2Nb1Ta1Mo (Ti). Effects of sodium chloride concentration on corrosion resistance were also studied. Corrosion behavior and pitting morphology of duplex stainless steel (DSS) and Ti alloys were evaluated through potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), and scanning electron microscopy (SEM). It was found that a decrease in pH significantly reduced the corrosion resistance of both alloys. Changes in chloride concentration and temperature had more substantial impact on corrosion behavior of DSS than on Ti alloys. Pitting corrosion was formed on DSS samples under all conditions, whereas crevice corrosion was developed on Ti samples with the presence of magnesium chloride at 90 ℃. In conclusion, magnesium chloride ions in an exceedingly strong acidity solution appear to interact with re-passivation process at the surface of these alloys and influence the resulting surface topography.

• Journal of Nutrition and Health
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• 제27권8호
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• pp.828-836
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• 1994

A low level exposure experiment was conducted on growing rats to investigate the accumulation and organ distribution of protein bound cadmium compared with cadmium chloride. Male Sprague-Dawley rats were fed for 21days with one of the semisynthetic diets, which contains cadmium as either bovine liver- or kidney meal bound cadmium, cadmium chloride with uncontaminated liver meal or cadmium chloride without organ meal, in the levels of ca. 0.5, 1 and 1.5mg/kg diet, respectively. After 21days of exposure cadmium was accumulated in liver, kidney and gastrointestinal tracts depending upon cadmium levels in diet. Inspite of very low cadmium accumulation in whole blood, it tends also to increase with dietary cadmium levels. The blood cadmium concentration of animals fed organ meal containing diets was about 4-7 fold higher than that without organ meal, regardless of cadmium was intrinsically bound to protein or not. However, significant effects of organ protein on cadmium accumulation in liver, kidney and digestive tracts were not detectable, when cadmium was supplemented as cadmium chloride. On the other hands, animals fed diet containing ca. 1.5mg Cd/kg as organ bound cadmium retained more cadmium in liver, kidney and digestive tracts compared to cadmium chloride with organ meal, whereby the increase of cadmium concentration in kidney was greater then in liver. However, when the concentration of protein bound cadmium was<1mg/kg diet, organ bound cadmium was not significantly different from cadmium chloride in bioavailability and organ distribution. From this result it is suggested that the intestinal absorption of protein bound cadmium is influenced of the amount of cadmium bound in protein. When cadmium concentration in protein is relatively low, protein bound cadmium seems to be absorbed in the same way as cadmium ions are absorbed. However, when the concentration is high, at least a small amount of intact protein bound cadmium could be absorbed and accumulated selectively in kidney.