• Analytical Science and Technology
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• v.12 no.5
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• pp.403-407
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• 1999

A method for detecting chlorine dioxide in drinking water was developed by the modified iodometric titration. This method requires prior removal of interfering chemicals such as chlorine and/or other oxidants: the interferents are removed by $N_2$ purging. Chlorite and chlorate were successfully quantified by the ion chromatography-conductivity detection. Stabilized chlorine dioxide that is commercially available contained only traces of chlorine dioxide (0.01-0.09%). In reality, its main component is chlorite.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 1999.04a
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• pp.78-83
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• 1999

In this paper the extinction coefficients of molecule chlorine ($Cl_2$), chlorine dioxide (ClO$_2$), hypochlorous acid (HClO), chlorous acid ($HClO_2$$_2$) were determined using a PDA UV-VIS spectrophotometer. Based on these, the concentrations of $Cl_2$, $ClO_2$, and HClO in general chlorine dioxide bleaching liquor can be measured. The concentrations of $Cl_2$, $ClO_2$ and $HClO_2$ produced during the generation of methanol based chlorine dioxide generator can also be determined use the same method. The method was thought to be able to give more information in chlorine dioxide bleaching chemistry if combine its use with titration and ion chromatography.

• Journal of Environmental Science International
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• v.8 no.2
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• pp.211-219
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• 1999

Surface complexation models(SCMs) have been performed to predict metal ion adsorption behavior onto the mineral surface. Application of SCMs, however, requires a self-consistent approach to determine model parameter values. In this paper, in order to determine the metal ion adsorption parameters for the triple layer model(TLM) version of the SCM, we used the zeta potential data for Zeolite and Kaolinite, and the metal ion adsorption data for Pb(II) and Cd(II). Fitting parameters determined for the modeling were as follows ; total site concentration, site density, specific surface area, surface acidity constants, etc. Zeta potential as a new approach other than the acidic-alkalimetric titration method was adopted for simulation of adsorption phenomena. Some fitting parameters were determined by the trial and error method. Modeling approach was successful in quantitatively simulating adsorption behavior under various geochemical conditions.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.30 no.4
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• pp.59-68
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• 1998

This study was to investigate the effect of chitosan molecular weight, its charge density, and its surface coating treatment on the antibacterial properties of paper. For this study, E.coil was used for antibacterial experiment. Results obtained were as follows : 1. The antibacterial properties of chitosan was significant on the surface-treated sheet. 2. Antibacterial property surface treatment was appeared to be effective when film was formed on the paper surface. 3. The antibacterial properties of chitosan-treated paper was dependent on the amount and the molecular weight of chitosan used. The lower the molecular weight of the chitosan down to 30,000 the better the antibacterial properties in this experiment. 4. Determination of the degree of chitosan-deacetylation by colloidal titration method was consistent with the more complicated and conventional FT-IR method.

• Journal of the Korean Society of Food Science and Nutrition
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• v.1 no.1
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• pp.25-31
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• 1972

The Undaria pinnatifida collected in the waters of Dongbaek Island were grouped into young and adult ones and calcium and iron contents of each were analyzed by parts, i.e., separately for blade, stripe, and sporophyll by potassium permanganate titration method and spectrophotometric method respectively (O-phenanthrolin used). The results showed that the blades contain higher percentage of calcium than other parts both in young and adult seaweeds and that proportionately twice as much iron is contained in the blades than in the stripes.

• Journal of the Korean Chemical Society
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• v.13 no.4
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• pp.313-316
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• 1969

In this paper a simple and rapid method is described for the determination of lead in monazite. A monazite sample was dissolved with hot concentrated sulfuric acid and diluted to 200 ml with distilled water. Lead is quatitatively separated by coprecipitating with strontium. Lead-strontium sulfate is dissolved in 3N NaOH soluion. An excess Zn-EDTA is added. The remaining zinc ion is titrated with standard 0.01 M EDTA solution using xylenol orange as indicator at pH 5 in the presence of KCN and acetyl acetone as masking agents.

• Journal of Institute of Control, Robotics and Systems
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• v.19 no.10
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• pp.891-895
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• 2013

This paper proposes the development of a new method for online analysis which measured acid concentration in a pickling line. Pickling is the most important step to remove surface scale layers and is strongly depending on the exactly controlled pickling liquor composition. Today, there is no feasible system available for the online control of pickling lines. Within this paper, new methods for online analysis of pickling liquors have been tested and implemented into an overall pickling process control tool. This method measured simultaneously the hydrochloric acid and iron ion concentration in a solution of hydrochloric acid by measuring the ultrasonic speed, the solution temperature, and the electrical conductivity. Experimental results showed excellent precision and the measurement error was ${\pm}2g/l$ compared with the neutralization titration measurement.

• Journal of the Korean Chemical Society
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• v.25 no.2
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• pp.67-74
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• 1981

The dissociation constants of benzoic acid, p-methoxybenzoic acid and p-nitrobenzoic acid have been determined at $25^{\circ}C$ in ethanol-water mixtures containing 0, 10, 20, 30, 40, 50, 65 and 80 weight % ethanol by the direct conductance measurements and the method involving titration of the acid sample with perchloric acid reagent. The results by the two methods have been discussed and compared with those by other methods.

• Journal of the Korean Ceramic Society
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• v.30 no.11
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• pp.933-940
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• 1993

SO42-/Al2O3 powder was prepared by the coprecipitation method from the Al(NO3)3.9H2O and NH4OH and followed by being treated with various concentrations of sulfuric acid. The characterization of these powders was performed with XRD, BET and FT-IR. The surface charge density at alumina/KCl(aq) interface was measured by potentiometric titration method. From the experimental data it was shown that acid strength, specfic surface area, and structure of surface treated alumina were independent on the amount of exchanged SO42-. However, the acid amounts of alumina were increased with the amounts of SO42- formed on alumina surface. The relation between the acid amount of SO42- ion exchanged alumina surface and the surface charge density for SO42-/Al2O3/KCl(aq) interface was investigated.

• Bulletin of the Korean Chemical Society
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• v.15 no.11
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• pp.1001-1003
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• 1994

A series of phosphodiesters of p-nitrophenyl phosphoryl derivatives were synthesized and used as a model substrate for phospholipase D (PLD). The phosphodiester substrates were synthesized from p-nitrophenyl phosphorodichloridate and corresponding alcohols with different chain lengths and polar groups. To measure the activity of PLD, either spectroscopic method for p-nitrophenol or pH-stat titration method was employed. For each substrate, effects of substrate concentration, pH, and $Ca^{2+}$ ion were examined. The kinetic parameters $V_{max}$ for the different substrates were varied depending on the chain lengths or charge of the alcohols. No calcium effect was observed in the hydrolysis of neutral and negatively charged alcohol derivatives, while positively charged choline derivative showed a strong $Ca^{2+}$ ion dependence.