• Analytical Science and Technology
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• v.9 no.2
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• pp.161-167
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• 1996

An investigation was made of possible ways in which one could control the relative rates of cadmium deposition and hydrogen evolution by binary additive systems. Benzyl alcohol was employed as an additives due to its ability to form a hydrophobic film which inhibit the electroreduction of water to form hydrogen. The second additive was chosen to make the cadmium(II) ion less hydrophilic and increase its ability to cross the hydrophobic benzyl alcohol film and be electrodeposited at the cathode. It was shown by voltammetric and current efficiency studies that ion pairing and complexing additives could be used to accelerate the reduction of cadmium in the presence of the benzyl alcohol film. It was also shown that the benzyl alcohol film lowered the dielectric constant of the solution near the electrode enough to obtain ion pairing between the sodium ion and the negative chloride complex of cadmium and accelerate the reduction of the cadmium. This acceleration did not occur in the sulfate solution in the absence of chloride since cadmium(II) is primarily present as a positive aquo complex and ion pairing, if it occured, would not accelerate but would hinder reduction of cadmium.

• Journal of the Korean Data and Information Science Society
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• v.21 no.3
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• pp.535-546
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• 2010

There are two methods in grouping customers for micro marketing promotion. The one is based on how much they paid and the other is based on how many times they purchased. In this study we are interested in the repurchase probability of customers. By analysing the customer's transaction data and demographic data, we develop a forecasting model of repurchase and make epurchase indexes of them. As a modeling tool we use the logistic regression model. Finally we categorize the customers into five groups in according to their repurchase indexes so that we can control customers effectively and get higher profit.

• Horticultural Science & Technology
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• v.28 no.4
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• pp.638-647
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• 2010

The genetic relationships in 5 species of $Ligularia$ were investigated using RAPD (Randomly Amplified Polymorphic DNA) and ITS (Internal Transcribed Spacer) sequences analyses. In RAPD analysis, sixty three of 196 arbitrary primers showed polymorphism. The amplified fragments ranged from 0.2 to 1.6 kb in size. The dendrogram was constructed by the UPGMA clustering algorithm based on genetic similarity of RAPD markers. A total of 16 accessions were classified into 5 major groups corresponding each species at the similarity coefficient value of 0.77. In the ITS sequence analysis, the size of ITS 1 was varied from 248 to 256 bp, while ITS 2 was varied from 220 to 222 bp. The 5.8S coding region was 164 bp in lengths. Forty nine sites (10.2%) of the 478 nucleotides were variable, and the G+C content of ITS region ranged from 49.4 to 53.5%. In the ITS tree, five species of $Ligularia$ were monophyletic, and $L.$ $taquetii$ was the first branching within the clade. $Ligularia$ $intermedia$ formed a clade with $L.$ $fischeri$ var. $spiciformis$ (BS=79), and $L.$ $stenocephala$ and $L.$ $fischeri$ were also claded. Two data sets were congruent, except of the position of $L.$ $fischeri$ var. $spiciformis$.

• Korean Journal of Plant Taxonomy
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• v.38 no.4
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• pp.371-388
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• 2008

Phylogenetic studies were conducted for 35 populations of the subfamily Coryloideae (Betulaceae) based on waxy gene of nuclear DNA and atpB-rbcL intergenic spacer region of chloroplast DNA. Waxy data analysis suggest that Coryloideae is monophyletic; Corylus is monophyletic and basally branching within the subfamily Coryloideae; Ostryopsis is sister to the Carpinus and Ostrya clade, and the Ostrya is monophyletic (BS=86, PP=99). AtpB-rbcL intergenic spacer region analysis shows that Ostryopsis appeared as the most basal clade within the Coryloideae; Corylus is monophyletic(BS=98, PP=100) and placed between Carpinus-Ostrya and Ostryopsis clade; Carpinus and Ostrya formed a clade with a high support value(BS=100, PP=100). Carpinus sect. Carpinus is monophyletic, whereas sect. Distegocarpus is paraphyletic in the waxy tree. Corylus formed two subclades, but discordance at the infrageneric classification based on morphological characters. In the atpB-rbcL tree, Carpinus and Corylus taxa form a polytomy within the each clade. Results from the two data sets differ mainly in the relative position of Ostryopsis, the monophyly of Ostrya, and the relationships within the Carpinus-Ostrya clade. Further studies are needed for clarify the taxonomic position and the generic limitation.

• Journal of the Korean Chemical Society
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• v.24 no.6
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• pp.444-451
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• 1980

In order to further elucidate the process of electron solvation in liquids, the medium effect, as the difference between the free energy of $H^+$ in aqueous and non-aqueous states (${\Delta}{\Delta}G_0$), of THF-water mixtures has been investigated. (${\Delta}{\Delta}G_0$) were determined by electromotive force masurements of the cell Pt$H_2Q$, Q, HCI, THF, $H_2O$|KC1 | $Hg_2Cl_2$|Hg(Pt), where $H_2Q$ and Q are hydroquinone and quinone respectively. The effect of dielectric constant on the difference of free energy and the absorption energy of solvated electrons have been studied. For the consideration of these effect the polymerization of water in THF has been studied. Near infrared spectrum of O-H stetching energy has been used to measure the extent of water aggregates. The expermental results indicate that at least in some composition of binary mixtures the electrons or other ions are solvated preferentially with one component of solvents.

• Journal of the Korean Electrochemical Society
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• v.15 no.4
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• pp.256-263
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• 2012

This study was performed to investigate the separation of cesium cations by using an electrochemical ion exchanger of nickel hexacyanoferrate($KNiFe(CN)_6$) film electrode. Potential, current, and charge passing through the cyclic voltammograms were measured in singular and binary solutions of 1.0M $NaNO_3$ and 1.0M $CsNO_3$. Before and after each experiment, the structural morphology and atomic composition of $KNiFe(CN)_6$ were analyzed by SEM and EDS, respectively. The ion selectivity of $KNiFe(CN)_6$ was also observed by the voltammograms and atomic compositions measured in the solution alternated between sodium and cesium. As the result of this study, it was found that the electrically switched $KNiFe(CN)_6$ ion exchanger had the significant advantage of 40 times or longer durability than conventional organic or inorganic ion exchanger. It was also shown that the $KNiFe(CN)_6$ ion exchanger had high selectivity for cesium over sodium.

• Journal of the Mineralogical Society of Korea
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• v.5 no.1
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• pp.6-13
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• 1992

Thermodynamic data of mineral reactions were used to construct a phase diagram for the formation of illite from andalusite at one bar and 325${\circ}C$ in the hydrothermal alteration. Based on chemical compositions, the free energy of formation of illite coexisting with andalusite was calculated by assuming the ideal mixing ina bunary system consisting of muscovite and pyrophyllite components. For illite with structural formula $K_{0.86}Al_{2.93}Si_{3.03}O_{10}(OH)_2$, its free energy of formation is -1147.727 kcal/mole at the condition under consideration. The stability area of illite is more narrow than that of end-member muscovite and prefers lower activity of silica. Illite was formed by hydration of andalusite while pyrophyllite decomposed. Illitization took place preferentially at margin and/or along fractures of andalusite.

• Korean Journal of Plant Resources
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• v.26 no.4
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• pp.457-462
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• 2013

Molecular study were conducted to evaluate taxonomic identities of Echinochloa crus-galli (L.) Beauv. and Echinochloa crus-galli var. echinata (Willd.) Honda in Dokdo. Echinochloa crus-galli complex of two species 26 individuals analyse based on nuclear ribosomal DNA (ITS region) and cpDNA (trnH-psbA, trnL-F). At a result, two species were same sequence. Characters the length of the lemma and the length of the awn traits were identity of the species was unclear. According to, Taxonomy treatments that is based on existent morphological characters should thinks again. On the other hand, in the case of ITS, Echinochloa crus-galli (L.) Beauv. and Echinochloa crus-galli var. echinata (Willd.) Honda at the Dokdo forms from other clades with individuals that is collected at land area and Ulleungdo. These result is showing that is flowing independent evolution trends.

• Journal of the Korean Chemical Society
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• v.44 no.6
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• pp.592-599
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• 2000

The fine particles of binary ceramic composite of titania-partially-stabilized zirconia(TPSZ) were synthesized by ultrasonic spray pyrolysis at the various temperatures, compositions and concentrations and the effects of process factors for synthesis on the characteristics of fine particles were discussed. The starting salt solutions were prepared to have the ionic concentrations of 0.025~0.1 M aqueous solutions. The fine particles were prepared to have the compositions of 90~97.5 wt% of $ZrO_2$ and 2.5~10 wt% of $TiO_2$. The temperatures for particle synthesis were regulated to be 400~550$^{\circ}C$ as a drying zone, 800~1100$^{\circ}C$ as a pyrolysis zone. The produced fine particles were collected by a wet process and analyzed to investigate characteristic properties after being dried. The compositions of ceramic fine particles were determined by Inductively Coupled Plasma-Atomic Emission Spectroscopy(ICP-AES) technique and phases, morphologies and particle sizes of those were investigated by Raman Spectroscopy, X-ray diffraction(XRD), Scanning Electron Microscopy(SEM), Transmission Electron Microscopy(TEM) and Particle Size Analyzer(PSA) techniques.

• Clean Technology
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• v.18 no.4
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• pp.347-354
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• 2012

In this study, simulation works have been performed for the $CO_2$ removal process contained in the DME production process using NMP (N-methyl-2-pyrrolidone) as a solvent. PRO/II with PROVISION release 9.1 at Invensys was used as a chemical process simulator and NRTL activity coefficient model with Henry's law option and Soave-Redlich-Kwong equation of state were used for thermodynamic models. For the determination of the binary interaction parameters in NRTL model, regression works have been performed to match the experimental thermodynamic data. Optimal feed tray location which minimizes the reboiler heat duty was determined.