• Journal of Soil and Groundwater Environment
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• v.14 no.6
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• pp.29-34
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• 2009

In this study, a chloride ion probe as a direct measurement for perchlorate reduction was used to determine whether biological perchlorate reduction was inhibited by other electron acceptors ($O_2$ and ${NO_3}^-$) and to investigate competition of electron acceptors for using electron donors. Profiles of chloride production (= perchlorate reduction) in flasks containing perchlorate reducing populations were monitored by a chloride ion probe. Biological reduction of 2 mM perchlorate was inhibited by 2 mM nitrate that chloride production rate was decreased by 30% compared to perchlorate used as the only electron acceptor and chloride production rate was decreased by 70% when acetate was limited. Reduction of 2mM perchlorate was completely inhibited by oxygen at 7~8 mg/L, regardless of acetate excess / limitation.

• Journal of the Korea Institute of Building Construction
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• v.20 no.1
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• pp.1-9
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• 2020

Chloride ion, which penetrates into the cement composites from the outside, generally diffuses by the concentration gradient. Chloride ions are adsorbed by the chemical reaction with cement hydrates. Recent studies have shown that anion exchange resin (AER) powder can effectively adsorb the chloride ion in the cement composites, and thus, the cement composites containing AER have a high chloride adsorption capacity and a good resistance for chloride penetration. In this study, the chloride adsorption ability of the AER powder was investigated under the conditions of distilled water and calcium hydroxide saturated solution to determine if the AER powder is less effective to increase the chloride adsorption ability after grinding process. The chloride adsorption ability of AER powder was compared with the previous research about the chloride adsorption of AER bead. In addition, the compressive strength, chloride diffusion coefficient (using NT Build 492 method), and the chloride profile of cement mortar substituted with AER powder were investigated. There was no decrease in the chloride adsorption capacity of AER powder but increase in the kinetic property for chloride adsorption after the grinding process. The AER powder could absorb the chloride ion in the mortar quickly, and showed better chloride ion adsorption ability than the cement hydrates.

• Journal of the Korea Concrete Institute
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• v.20 no.4
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• pp.415-421
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• 2008

Reinforced concrete starts to corrode when the chloride ion concentration which is the sum of included in concrete and penetrated from environments exceeds a certain level of critical chloride concentration. Therefore each country regulates the upper bounds of chloride amount in concrete and the regulations are different for each country due to its circumstances. In this study, the critical threshold chloride content according to unit cement amount is empirically calculated to propose a reasonable regulation method on the chloride amount. As a result, the critical threshold chloride content increases considerably according to cement content and it agrees with the established theories. The present regulations on total chloride amount 0.3 or 0.6 kg chloride ions per $1\;m^3$ of concrete does not reflect the influences of mix design, environmental conditions and etc. So it can be said that it is more reasonable to regulate the critical threshold chloride content by the ratio of chloride amount per unit cement content than by the total chloride content in $1\;m^3$ of concrete.

• Journal of Physiology & Pathology in Korean Medicine
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• v.27 no.6
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• pp.759-763
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• 2013

This experiment was performed to investigate whether 50% ethanol extracts of the combined-preparation of Longanae Arilus, Chrysanthemi Flos, Zizyphi Fructus and Ginseng Radix alba (CPE) has hypnotic effects and/or enhances pentobarbital-induced sleeping time. Locomotor activity was evaluated using a ambulometer of tilting-type. The sedative-hypnotic effects were evaluated by measuring the sleeping onset time and sleeping time in pentobarbital-treated mice 30 min. after oral administration of CPE and muscimol. The intracellular $Cl^-$ concentration of cerebellar granule cells was estimated using $Cl^-$ sensitive fluorescence probe N-(ethoxycarbonylmethyl)-6-methoxyquinolinium (MQAE). CPE (150 mg/kg) decreased the locomotor activity, but CPE itself did not induce sleep. However, CPE reduced sleeping onset and prolonged sleeping time induced by pentobarbital (42 mg/kg). In addition, CPE (2 ${\mu}g/ml$) and pentobarbital (2.5 ${\mu}M$) itself did not affect on the chloride influx in primary cultured cerebellar granule cells, but the combination of CPE and pentobarbital (2.5 ${\mu}M$) increased the chloride influx onto the cells. In conclusion, it is suggested that CPE might augment pentobarbital-induced sleep through the increase of chloride influx.

• Corrosion Science and Technology
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• v.14 no.2
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• pp.85-92
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• 2015

An on-line corrosion rate measurement system was developed using a personal computer, a data acquisition board and program, and a 2-electrode corrosion probe. Reliability of the developed system was confirmed with through comparison test. With this system, the effect of sodium nitrite ($NaNO_2$) as a corrosion inhibitor were studied on iron and aluminum brass that were immersed in sodium chloride (NaCl) solution. Corrosion rate was measured based on the linear polarization resistance method. The corrosion rates of aluminum brass and iron in 1% NaCl solutions were measured to be 0.290 mm per year (mmpy) and 0.2134 mmpy, respectively. With the addition of 200 ppm of $NO{_2}^-$, the corrosion rates decreased to 0.0470 mmpy and 0.0254 mmpy. The addition of $NO{_2}^-$ caused a decrease in corrosion rates of both aluminum brass and iron, yet the $NO{_2}^-$ acted as a more effective corrosion inhibitor for iron. than aluminum brass.

• Korean Journal of Materials Research
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• v.16 no.11
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• pp.710-714
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• 2006

The purpose of this study is to identify the effect of additives and composition on copper surface morphology and mechanical characteristics by copper electrodeposition. Additives such as hydroxy ethyl cellulose(HEC), chloride ion were used in this study. Electrochemical experiments allied to SEM, XRD, AFM and four- point probe were performed to characterize the morphology and mechanical characters of copper in the presence of additives. Among various electrodeposition conditions, the minimum surface roughness of copper foil was obtained when electrodeposited at the current density of 200 mA/$cm^2$ for 68 seconds with 2 ppm of HEC. The minimum value of surface roughness(Rms) was 107.6 nm. It is copper foil is good for electromigration inhibition due to preferential crystal growth of Cu (111) deposited in the electrolyte containing chloride ions(10 ppm) and HEC(1 ppm).

• Journal of Photoscience
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• v.11 no.1
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• pp.19-23
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• 2004

The sharp-line absorption spectrum of microcrystalline samples of cis-[Cr(cycb)$Cl_2$]Cl (cycb=rac-5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane) has been measured between 13000 and $16000 cm^{-1}$ at temperatures down to 5K. The 77K emission and excitation spectra, and 298 K infrared and visible absorption spectra have also been measured. The nine electronic bands due to spin-allowed and spin-forbidden transitions were assigned. Using the observed transitions, a ligand field analysis has been performed to probe the ligand field properties of coordinated atoms in the title chromium(III) complex. The zero-phonon line in the sharp-line absorption spectrum splits into two components by $240 cm^{-1}$ , and the $large ^2$$_E{g}$ splitting can be reproduced by the modem ligand field theory. It is confirmed that nitrogen atoms of the macrocyclic cycb ligand have a strong $\sigma$-donor character, but chloride ligand has weak $\sigma$- nd $\pi$-donor properties toward chromium(III) ion.n.