• Journal of the Korean Chemical Society
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• v.39 no.4
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• pp.275-280
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• 1995

The electron transfer reactions between cis-[Co(en)2(NO2)2]+ and rac-[Co(Y)]2-(Y=EDTA, PDTA, CyDTA) have been investigated in the presence of hydrogen ion. From the kinetic data, it has been found that electron transfer reactions between cis-[Co(en)2(NO2)2]+ and rac-[Co(Y)]2- proceed via inner-sphere pathway by catalysis of hydogen ion. The stereoselectivity in the electron transfer reactions between optically active △-cis-[Co(en)2(NO2)2]+ and rac-[Co(Y)]2- produced 6.0, 2.9, 3.0% e.e.(e.e.=enantiomeric excess) of △-[Co(EDTA)]-, △-[Co(PDTA)]- and △-[Co(CyDTA)]-, respectively. Based upon this observation, it seems that △-cis-[Co(en)2(NO2)2]+ is associated with rac-[Co(Y)]2- at first, and followed by the electron transfer reaction. Therefore, it was suggested that stereoselective electron transfer reaction between △-cis-[Co(en)2(NO2)2]+ and rac-[Co(Y)]2- proceed through both inner-sphere by the proton catalysis and outer-sphere with ionic association.

• Communications of the Korean Mathematical Society
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• v.33 no.2
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• pp.639-650
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• 2018

Finding a solution for the Legendre equation is difficult. Especially if it is as a part of the Laplace equation solving in the electric fields. In this paper, first a problem of the generalized differential transform method (GDTM) is solved by the Sturm-Liouville equation, then the Legendre equation is solved by using it. To continue, the approximate solution is compared with the nth-degree Legendre polynomial for obtaining the inner and outer potential of a sphere. This approximate is more accurate than the previous solutions, and is closer to an ideal potential in the intervals.

• Bulletin of the Korean Chemical Society
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• v.32 no.8
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• pp.2599-2606
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• 2011

The fluorescence of ethidium bound to DNA, poly[d(A-T)$_2$], and poly[d(G-C)$_2$] at a [ethidium]/[DNA] ratio of 0.005 was quenched by porphyrins when both ethidium and the porphyrins simultaneously bound to the same polynucleotide. The quenching was tested using the "inner sphere" and the "Forster resonance energy transfer" (FRET) models, with the latter found to contribute, at least in part, to the quenching. Meso-tetrakis(N-methylpyridinium-4-yl)porphyrin (TMPyP) exhibited a higher quenching and FRET efficiency than cis-bis(N-methylpyridinium-4-yl)porphyrin (BMPyP) for all of the tested DNA and polynucleotides, demonstrating that energy transfer efficiency is affected by the number of positive charges of porphyrins.

• Journal of the Korean Chemical Society
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• v.39 no.1
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• pp.29-34
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• 1995

The rates for the oxidation reaction of l-ascorbic acid by Cu(Ⅱ)-polyamine complexes were measured by Onish's method at the pH 4.6. The oxidation process of l-ascorbic acid is proposed to occur by the inner-sphere mechanism that involves the formation of a Cu(Ⅱ)-ascorbic acid complex and electron transfer at the rate-determining step.

• Bulletin of the Korean Chemical Society
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• v.27 no.2
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• pp.251-254
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• 2006

The formation of polyaniline (PANI) in the reverse micelles of poly(oxyethylene) nonylphenyl ether, $(NP5, H(CH_2)_9Ph(OC_2H_4)_5OH)$, was investigated by small-angle neutron scattering (SANS). The reverse micellar solution containing initiators in the inner part of reverse micelle was prepared with surfactant (NP5), water, cyclohexane and an initiator (ammonium persulfate (APS)). The core-shell sphere model containing smearing effect reveals that the polymerization occurs on the shell layer of the reverse micelles. Shell thickness averages varied from 48 $\AA$ to 109 $\AA$ with increases of monomer concentration.

• Bulletin of the Korean Chemical Society
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• v.11 no.4
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• pp.303-306
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• 1990

Kinetic studies were carried out for the redox reaction of $[Co(NH_3)_4(C_2O_4)]^+$ with aqueous $[Fe(H_2O)_6]^{2+}$ solution in the present of $H^+$ by UV/VIS-spectrophotometric method. It was found that the order of $H^+$ for the reaction is first one in the higher $H^+$ concentration range of $1.67×10^{-1} M{\sim}1.00 M,$ while second order in the lower range of $6.30×10^{-2} M{\sim}1.67{\times}10^{-1} M.$ Reaction order of the substrates was found to be first order with respect to each of them. Accordingly overall reactions are third or fourth order. The results of calculation for the Extended Huckel Molecular Orbital theory contribute to estimate the preferred intermediates, bridging form of binuclear complex. On the basis of these results, we propose that this redox reaction proceed via inner-sphere reaction mechanism.

• Journal of the Korean Home Economics Association
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• v.44 no.8
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• pp.181-198
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• 2006

The purpose of this study is to understand modernization process of korean housing during the past one century. To following up the changes of everyday lives of common peoples, magazines, news papers, tourist's records and gossip items were collected and interpreted from the microscopic point of view. In this study arguments on 'modernity' of korean housing was focused on some issues, thus, separation, differentiation, individualization, as well as privatization. Concrete discourses are; firstly, spatial isolation of housing and urban place each other, secondly, functional division of inner spaces of housing, and lastly, guarantee of privacy sphere. Historical changes of housing showed some meaningful phenomena. Before modernization housing was place of reproduction and consume at the same time. However after modern urban space came into existence and work and rest were separated, housing gained only mono function. Thus, housing have only one meaning as private place for nuclear family, that is "Home, Sweet Home." Instead of past multi-functional rooms, functional prescribed rooms, for example, dinning room, were newly born. In the past, the boundary between public and private sphere was not clear. For examples, everyday experiences of family were extended to the street and in the house in most cases spaces were shared. But after modernization the scale of individual spaces become larger and private life can be secured. Consequently, history of everyday life from traditional agricultural society to industrialized modern society demonstrates the structural context between the micro and macro dimension in the fields of human life. In other words, everyday lives and macro history response each other and create new perception of time-space structure in the modern housing.

• Journal of the Mineralogical Society of Korea
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• v.11 no.1
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• pp.20-31
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• 1998

Adsorption of metal elements onto illite and halloysite was investigated at $25^{\circ}C$ using pollutant water collected from the gold-bearing metal mine. Incipient solution of pH 3.19 was reacted with clay minerals as a function of time: 10 minute, 30 minute, 1 hour, 12 hour, 24 hour, 1 day, 2 day, 1 week, and 2 week. Twenty-seven cations and six anions from solutions were analyzed by AAs (atomic absorption spectrometer), ICP(induced-coupled plasma), and IC (ion chromatography). Speciation and saturation index of solutions were calculated by WATEQ4F and MINTEQA2 codes, indicating that most of metal ions exist as free ions and that there is little difference in chemical species and relative abundances between initial solution and reacted solutions. The adsorption results showed that the adsorption extent of elements varies depending on mineral types and reaction time. As for illite, adsorption after 1 hour-reaction occurs in the order of As>Pb>Ge>Li>Co, Pb, Cr, Ba>Cs for trace elements and Fe>K>Na>Mn>Al>Ca>Si for major elements, respectively. As for halloysite, adsorption after 1 hour-reaction occurs in the order of Cu>Pb>Li>Ge>Cr>Zn>As>Ba>Ti>Cd>Co for trace elements and Fe>K>Mn>Ca>Al>Na>Si for major elements, respectively. After 2 week-reaction, the adsorption occurs in the order of Cu>As>Zn>Li>Ge>Co>Ti>Ba>Ni>Pb>Cr>Cd>Se for trace elements and Fe>K>Mn>Al, Mg>Ca>Na, Si for major elements, respectively. No significant adsorption as well as selectivity was found for anions. Although halloysite has a 1:1 layer structure, its capacity of adsorption is greater than that of illite with 2:1 structure, probably due to its peculiar mineralogical characteristics. According to FTIR (Fourier transform infrared spectroscopy) results, there was no shift in the OH-stretching bond for illite, but the ν1 bond at 3695 cm-1 for halloysite was found to be stronger. In the viewpoint of adsorption, illite is characterized by an inner-sphere complex, whereas halloysite by an outer-sphere complex, respectively. Initial ion activity and dissociation constant of metal elements are regarded as the main factors that control the adsorption behaviors in a natural system containing multicomponents at the acidic condition.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.4
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• pp.287-293
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• 2009

This study investigated the influence of ionic strength on the adhesion and release of bacteria (Escherichia coli, Bacillus subtilis, and Staphylococcus aureus) in quartz and iron-coated sands using column experiments. Results show that the mass recovery remained constant (E. coli = 13.7${\pm}$0.5%, B. subtilis = 9.8${\pm}$1.3%, S. aureus = 13.0${\pm}$2.1%) in iron-coated sand while it decreased from 80.7 to 45.3% (S. aureus) in quartz sand with increasing ionic concentrations from 1 to 100 mM. As the ionic concentrations of leaching solution was lowered from 100 to 0.1 mM, average 39.1% of bacterial detachment was quantified from quartz sand, but no bacterial release was observed in iron-coated sand. The phenomenon observed in iron-coated sand can be attributed to the inner-sphere complexes between bacteria and coated sand, which have minimal effect from ionic strength. This study improves our knowledge regarding the bacterial interaction with surface-modified porous media.

• Journal of the Korean Institute of Landscape Architecture
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• v.41 no.5
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• pp.57-67
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• 2013

The studies of Korean traditional gardens have been a lot of diachronic approaches through ancient documents and on-site investigation. Previous research has focused on the characteristics that are inherent symbolism of the traditional landscape space, such as site characteristics. There are many studies for inner gardens, outer gardens and other influential ranges of gardens of the location characteristics. However, studies on the scale of external gardens were not satisfactory from a quantitative perspective. Unlike private life sphere, quantitative analysis was conducted on the role of a sphere of public community life for outer gardens. Visibility analysis was performed through the existing literature and GIS programs to estimate the magnitude of the outer garden. When it was compared with Min G. H.(1982) research, it is almost the same if it is estimated to focus on Buyoung -bong(芙蓉峯) and Ip-am(立巖). Also, as a result of the fractal structure for a variety of symbols in the garden, fractal dimension in landscape elements is relatively concentrated, unlike in other areas. Thus, the external scale can be a means of cultural property protection out of the crucial perspective for the inner garden. There has been consideration of the cooperation with the visual complexity using the concept of fractal structure as one of the elements of landscape analysis.