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Application of the Homogenization Analysis to Calculation of a Permeability Coefficient (투수계수 산정을 위한 균질화 해석법의 적응)

  • 채병곤
    • Journal of Soil and Groundwater Environment
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    • v.9 no.1
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    • pp.79-86
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    • 2004
  • Hydraulic conductivity along rock fracture is mainly dependent on fracture geometries such as orientation, aperture, roughness and connectivity. Therefore, it needs to consider fracture geometries sufficiently on a fracture model for a numerical analysis to calculate permeability coefficient in a fracture. This study performed new type of numerical analysis using a homogenization analysis method to calculate permeability coefficient accurately along single fractures with several fracture models that were considered fracture geometries as much as possible. First of all, fracture roughness and aperture variation due to normal stress applied on a fracture were directly measured under a confocal laser scaning microscope (CLSM). The acquired geometric data were used as input data to construct fracture models for the homogenization analysis (HA). Using the constructed fracture models, the homogenization analysis method can compute permeability coefficient with consideration of material properties both in microscale and in macroscale. The HA is a new type of perturbation theory developed to characterize the behavior of a micro inhomogeneous material with a periodic microstructure. It calculates micro scale permeability coefficient at homogeneous microscale, and then, computes a homogenized permeability coefficient (C-permeability coefficient) at macro scale. Therefore, it is possible to analyze accurate characteristics of permeability reflected with local effect of facture geometry. Several computations of the HA were conducted to prove validity of the HA results compared with the empirical equations of permeability in the previous studies using the constructed 2-D fracture models. The model can be classified into a parallel plate model that has fracture roughness and identical aperture along a fracture. According to the computation results, the conventional C-permeability coefficients have values in the range of the same order or difference of one order from the permeability coefficients calculated by an empirical equation. It means that the HA result is valid to calculate permeability coefficient along a fracture. However, it should be noted that C-permeability coefficient is more accurate result than the preexisting equations of permeability calculation, because the HA considers permeability characteristics of locally inhomogeneous fracture geometries and material properties both in microscale and macroscale.

An Empirical Study on the Importance of Psychological Contract Commitment in Information Systems Outsourcing (정보시스템 아웃소싱에서 심리적 계약 커미트먼트의 중요성에 대한 연구)

  • Kim, Hyung-Jin;Lee, Sang-Hoon;Lee, Ho-Geun
    • Asia pacific journal of information systems
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    • v.17 no.2
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    • pp.49-81
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    • 2007
  • Research in the IS (Information Systems) outsourcing has focused on the importance of legal contracts and partnerships between vendors and clients. Without detailed legal contracts, there is no guarantee that an outsourcing vendor would not indulge in self-serving behavior. In addition, partnerships can supplement legal contracts in managing the relationship between clients and vendors legal contracts by itself cannot deal with all the complexity and ambiguity involved with IS outsourcing relationships. In this paper, we introduce a psychological contract (between client and vendor) as an important variable for IS outsourcing success. A psychological contract refers to individual's mental beliefs about his or her mutual obligations in a contractual relationship (Rousseau, 1995). A psychological contract emerges when one party believes that a promise of future returns has been made, a contribution has been given, and thus, an obligation has been created to provide future benefits (Rousseau, 1989). An employmentpsychological contract, which is a widespread concept in psychology, refers to employer and employee expectations of the employment relationship, i.e. mutual obligations, values, expectations and aspirations that operate over and above the formal contract of employment (Smithson and Lewis, 2003). Similar to the psychological contract between an employer and employee, IS outsourcing involves a contract and a set of mutual obligations between client and vendor (Ho et al., 2003). Given the lack of prior research on psychological contracts in the IS outsourcing context, we extend such studies and give insights through investigating the role of psychological contracts between client and vendor. Psychological contract theory offers highly relevant and sound theoretical lens for studying IS outsourcing management because of its six distinctive principles: (1) it focuses on mutual (rather than one-sided) obligations between contractual parties, (2) it's more comprehensive than the concept of legal contract, (3) it's an individual-level construct, (4) it changes over time, (5) it affects organizational behaviors, and (6) it's susceptible to organizational factors (Koh et al., 2004; Rousseau, 1996; Coyle-Shapiro, 2000). The aim of this paper is to put the concept, psychological contract commitment (PCC), under the spotlight, by finding out its mediating effects between legal contracts/partnerships and IS outsourcing success. Our interest is in the psychological contract commitment (PCC) or commitment to psychological contracts, which is the extent to which a partner consistently and deeply concerns with what the counter-party believes as obligations during the IS project. The basic premise for the hypothesized relationship between PCC and success is that for outsourcing success, client and vendor should continually commit to mutual obligations in which both parties believe, rather than to only explicit obligations. The psychological contract commitment playsa pivotal role in evaluating a counter-party because it reflects what one party really expects from the other. If one party consistently shows high commitment to psychological contracts, the other party would evaluate it positively. This will increase positive reciprocation efforts of the other party, thus leading to successful outsourcing outcomes (McNeeley and Meglino, 1994). We have used matched sample data for this research. We have collected three responses from each set of a client and a vendor firm: a project manager of the client firm, a project member from the vendor firm with whom the project manager cooperated, and an end-user of the client company who actually used the outsourced information systems. Special caution was given to the data collection process to avoid any bias in responses. We first sent three types of questionnaires (A, Band C) to each project manager of the client firm, asking him/her to answer the first type of questionnaires (A).

Study on the Improvement of Gill Nets and Trap Nets Fishing for the Resource Management at the Coastal Area of Yellow Sea - On the Entrapping Behavior of Fishes into Trap Nets in the Water Tank Experiment - (서해구 자원관리형 자망ㆍ통발 어구어법 기술개발에 관한 연구 - 수조에서의 통발에 대한 어군의 입롱행동 -)

  • 장호영;조봉곤;고광수;한민숙
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.39 no.1
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    • pp.56-62
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    • 2003
  • To investigate the entrapping behavior of blue crab, rock shell and green ling, which are mainly caught with the other trap nets in the coastal area of Yellow Sea, by the using duration of trap nets through the water tank experiment. We select the three kinds of trap nets which have different using duration such as new, 6 months and 12 months used one, and observe the entrapping ratio into the trap nets, respectively. In the mean while, in order to obtain the basic data for the estimate of mesh selectivity of the other trap nets, the entrapping behavior into the trap nets for green ling which has high activity compared to blue crab and rock shell, are examined to the three kinds of mesh size (35mm, 50mm and 65mm). The results are as follows ; 1. The mean entrapping ratio of blue crab by the using duration of trap nets in high with 4.4 fishes (44.0%) in the 6 months used one, become lower with 2.9 fishes (28.0%) in the new one, and with 2.0 fishes (20.0%) in the 12 months used one. 2. The mean entrapping ratio of rock shell by the using duration of trap nets in high with 7.3 fishes (36.7%) in the new one, and become lower with 7.2 fishes (35.8%) in the 6 months used one, and with 5.7 fishes (28.3%) in the 12 months used one. 3. The mean entrapping ratio of green ling by the using duration of trap nets in high with 3.4 fishes (34.0%) in the 6 months used one, and become lower with 3.0 fishes (30.0%) in the new one, and with 2.8 fishes (28.0%) in the 12 months used one. 4. The mean residual ratio of green ling by the mesh size of trap nets is high with 2.4 fishes (24.0%) in the 35mm mesh size, and become lower with 2.2 fishes (22.0%) in the 50mm mesh size and 2.0 fishes (20.0%) in the 65mm mesh size.

Development of Mixed-bed Ion Exchange Resin Capsule for Water Quality Monitoring (수질 중 질소와 인 모니터링을 위한 혼합이온교환수지 캡슐의 개발)

  • Park, Chang-Jin;Kim, Dong-Kuk;Ok, Yong-Sik;Ryu, Kyung-Ryul;Lee, Ju-Young;Zhang, Yong-Seon;Yang, Jae-E
    • Applied Biological Chemistry
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    • v.47 no.3
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    • pp.344-350
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    • 2004
  • This study was conducted to develop and assess the applicability of mixed-bed ion exchange resin capsules for water quality monitoring in small agricultural watershed. Recoveries of resin capsules for inorganic N and P ranged from 96 to 102%. The net activation energies and pseudo-thermodynamic parameters, such as ${\Delta}G^{o\ddag},\;{\Delta}H^{o\ddag},\;and\;{\Delta}S^{o\ddag}$ for ion adsorption by resin capsules, exhibited relatively low values, indicating the process might be governed by chemical reactions such as diffusion. However, those values increased with temperature coinciding with the theory. The reaction reached pseudo-equilibrium within 24 hours for $NH_4-N\;and\;NO_3-N$, and only 8 hours for $PO_4-P$, respectively. The selectivity of resin capsules were in the order of $NO_3\;^-\;>\;NH_4\;^+\;>\;PO_4\;^{3-}$, coinciding with that of encapsulated Amberlite IRN-150 resin. At the initial state of equilibrium, the resin adsorption quantity was linearly proportional to the mass of ions in the streams, but the rate of movement leveled off, following Langmuir-type sorption isotherm. The overall results demonstrated that the resin capsule system was suitable for water quality monitoring in small agricultural watershed, judging from the reaction mechanism(s) of the resin capsule and the significance of model in field calibration.

Influences of the Plant Growth under Beta-Rays Irradiation at Low Dose (저 선량 베타선의 조사에 의한 식물의 생장에 미치는 영향)

  • Lee, Byung-Koo;Im, In-Chul;Kim, Jong-Eon
    • Journal of radiological science and technology
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    • v.33 no.2
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    • pp.143-148
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    • 2010
  • This study is to analyze effects of the growth of Chunhyang Young Radish (CYR) and Altari Radish (AR) according to the exposure for 31 days at low dose ${\beta}$-rays. This test has one contrast sample and eleven test samples each as to AR and CYR. The seeds from contrast and test sample were planted in the culture soil after 8 seeds were chosen from each with identical condition. The accumulated dose of test samples has been measured at consistent time on a daily basis for 31 days. The growing process and germination have been measured twice at consistent time in each week. The number of leaves, length of first leave and weight have been acquired average value by measuring for 20 and 25 days, respectively after being planted. The result of test sample in case of 25 days shows that 5% increase in length and 36% increase in weight for AR each at accumulated dose 0.01 Gy compared to the contrast sample. And the length of CYR has increased by 13~17% and 1% at accumulated dose 0.01~0.08 Gy and 0.3 Gy compared to the contrast sample. For the weight at accumulated dose 0.05 Gy and 0.23 Gy has increased by 36% and 2% compared to contrast sample. As to the number of leaves, AR has increased by 0~50% at accumulated dose 0.01-0.32 Gy compared to contrast sample. It also shows that the CYR has increased to 0~67% at accumulated dose 0.01-0.62 Gy compared to contrast sample. As a result of this study, it indicates that both AR and CYR has generally increased in their length, weight, and the number of leaves at low level accumulated dose part 0.01~0.2 Gy. The size of cell, area of nucleus and density of cell for test sample has been observed quite similar to the ones from contrast sample through microscope. In conclusion, AR and CYR irradiated by ${\beta}$-rays have estimated that they are achieved a rapid growth at low level accumulated dose region corresponding to its radiation hormesis theory. Further studies need to confirm the correlation between the radiation hormesis and the growth of the plants.

Comparison of Uptake of Ionic and Tf-bound Fe-59 and Ga-67 in Transformed and Untransformed Cells (변형세포와 비변형세포에서 이온형과 Transferrin 결합형 Fe-59와 Ga-67 섭취율의 비교)

  • Sohn, Myung-Hee;Lee, Young-Hwan;Lee, Sang-Yong;Chung, Gyung-Ho;Han, Young-Min;Kim, Jong-Soo;Choi, Ki-Chul;Yim, Chang-Yeol
    • The Korean Journal of Nuclear Medicine
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    • v.30 no.1
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    • pp.145-151
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    • 1996
  • Pathways both mediated by and independent of transferrin(Tf) and the TfR have been described for the accumulation of iron. Although it is not clear whether the same systems take up iron and gallium, these pathways may suggest the contention that uptake of Ga-67 can, in fact, occur by both Tf-independent and Tf-dependent systems and may share with Fe-59 in part the same mechanism for uptake. The predominant system by which uptake of both radiometals occurs may be different in the degree of the transformation of tumor. Transformed(MMSV/3T3) and untransformed(BALB/3T3) cells were incubated with luM of Ga-67-citrate of Fe-59-chloride for 15 min. at $37^{\circ}C$ in either the presence or absence of Tf. After then, the monolayers were washed with HBSS or PBS, and the cells were solubilized in 1% SDS for gamma well counting and protein determinations. There were similarities, as well as differences, in the pattern of uptake of Fe-59 and Ga-67 presented both in ionic from and as bound to Tf. Both radiometals appeared gain to cells in either ionic or Tf-bound forms. Transformed cells appeared to accumulate more radiometal, either Ga-67 or Fe-59 in the presence of Tf than do the their untransforemd counterparts. Conversly the presentation of either radiometal in ionic form resulted in significantly greater accumulation of metal by the untransformed cells than those transformed. The efficiency for uptake of Ga-67 or Fe-59 in the absence of Tf was greater than for uptake of the Ga-Tf or Fe-Tf. However, the magnitude of difference in efficiency of uptake was greater for Fe-59(10-fold) than for Ga-67 (3-fold). Our results Supports the theory that both Tf-independent and Tf-dependent systems for the uptake of Ga-67 both systems operate oppositely between transformed cells and those untransformed, with uptake by the predominating in transformed cells by the Tf-mediated system and in untransformed cells by the Tf-independent. The uptake of Ga-67 by tumor may share with Fe-59 in part the same mechanism.

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기호학적 분석을 통한 영상애니메이션 연구

  • Lee Jong-Han
    • Broadcasting and Media Magazine
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    • v.10 no.1
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    • pp.85-98
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    • 2005
  • About the phenomenon of being imaged of everything, the scholars of the humanities who had studied on the simple reason structure in a text have been in a big agony how accept it. Especially, semiologists have studied about this for a long time and the points at issues of Saussure, Peirce as well as Umbeto Eco are more outstanding. Being based upon his philosophic interesting from medieval esthetics to modern semiotics, Eco was very concerned about the field of general esthetics and poputar arts like television and cartoons. He connected the mutual open-relations between 'signifier' and 'signified' debated in Semiotics with the open and vague modern arts and regarding it as a deviation from the custom, intensively studied the film-media. Saussure is a representative figure of semiotics and explained Sign and the character of semiotics as the division into two parts such as signifier/ signified, form/ substance, langue/ parole, synchrony/ diachrony. The triadic semiotics (the theory that Sign is composed of the triadic structure like sign, referent and interpretant) of Peirce put the new item- 'interpretant' in sign and referent to connect them and open the possibility to introduce time in to the Sign. In this paper, I try to analyze a cartoon film in the semiotic structure with the systemic, reasonable and logical approach and analysis as as possible. While the images shown through a film were depended on the romantic and impressional judge in the past, due to semiotics, it' s quite possible to correlate the procedure of symbolization to social coherence so that we analyze the incredible power of images to suck audiences with the systemetic Sign. I accept all ot film-images including a cartoon film as not the simple esthetic arts but a social custom and system, want to serve as a aid to properly understand world and humanbeings and prevent the film-image from being mystic. A cartoon and a cartoon film which were begun with the link of a text and an illustration give shape to all of images such as materials, places and even thoughts with a cartoon icon existed in only a cartoon. A cartoon and a cartoon film simply and exquistely conceptualize the complex and vague attribute of an organic creature and extend them infinetly beyond language. However, it can be exploited as a mysticism to temptate the general public and a faking material. In addition to that, it can distort our world-knowledge engaging a political power and the massive power of mass media. In this paper, being based on semiotics to approach a cartoon film in a scientific and organic system, I conclude that a non-linguistic cartoon expression is entangled with the manifold signs and implies the supplementary meanings just like a regular linguistic expression. It remarks that the iconic images of a cartoon film are composed of the social codes and can be analyzed on grounds of a linguistic system.

Speciation Mode Reconstruction for Lepilemur six species (L. mustelinus, L. edwardsi, L. dorsalis, L. leucopus, L. ruficaudatus, L. septentrionalis) Based on the Lepilemur Karyotype Analysis (여우원숭이속(Lepilemuridae)의 핵형 분석을 통해 나타난 Lepilemur 6종(L. mustelinus, L. edwardsi, L. dorsalis, L. leucopus, L. ruficaudatus, L. septentrionalis)의 종 분화 양상)

  • 정기윤
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.5 no.2
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    • pp.141-149
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    • 2004
  • The aim of this study was to test the validity of the hypothesis that the karyotypes of four species of Lepilemuridae were formed spontaneously from their ancestral hybrid karyotype. Hypothetical ancestral haploid Karyotype of Lepilemuridae is composed of 18 autosomes and X chromosomes. Lepilemur mustelinus karyotype has four tandem fused chromosomes and one Robertsonian translocated chromosome pairs. Lepilemur septentrionalis septentrionalis karyotype has only two pairs of translocated chromosomes. We reconstruct and suggest ancestral karyotype of LMU(ancLMU) and LSS(ancLSS), from which all four studied species were derived. Hybrids of ancLMU and ancLSS were formed and produce differently fused equilibrated gametes via circular form arrangement during gametogenesis. Five unit of trivalent homologous chromosome pairs were engaged in a circular form to give new gamete corresponding to the karyotype of L. dorsalis, orientation of one unit of trivalent was inversed in the circle to gave new gamete corresponding to the karyotype of L. leucopus. Seven homologous chromosome pairs were engaged in circular form to give haploid karyotype of Lepilemur ruficaudatus. Only one homologous chromosome pair is dissociated and the other chromosome pairs rearranged in the circle to form haploid karyotype of Lepilemur edwardsi. The new gametes could be produced from these circular forms. When the new gamete fertilized with the same type of gamete, The new homozygote is produced as existing L. dorsalis, L. leucopus, L. edwardsi and L. ruficaudatus. These results support the theory that new species could be formed in hybrid population through activated chromosome fusion, chromosome rearrangement in circular from at zygotene stage and production of equilibrated gametes to form homozygote new species.

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Time Dependent Evaluation of Corrosion Free Life of Concrete Tunnel Structures Based on the Reliability Theory (해저 콘크리트 구조물의 신뢰성 이론에 의한 시간 의존적 내구수명 평가)

  • Pack, Seung Woo;Jung, Min Sun
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.15 no.3
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    • pp.142-154
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    • 2011
  • This study predicted the probability of corrosion initiation of reinforced concrete tunnel boxes structures using the Monte Carlo Simulation. For the inner wall and outer wall in the tunnel boxes, exposed to airborne chloride ion and seawater directly respectively, statistical values of parameters like diffusion coefficient D, surface chloride content $C_s$, cover depth c, and the chloride threshold level $C_{lim}$ were examined from experiment or literature review. Their average values accounted for $3.77{\times}10^{-12}m^2/s$, 3.0% by weight of cement, 94.7mm and 45.5mm for outer wall and inner wall, respectively, and 0.69% by weight of cement for D, $C_s$, c, and $C_{lim}$, respectively. With these parametric values, the distribution of chloride contents at rebar with time and the probability of corrosion initiation of the tunnel boxes, inner wall and outer wall, was examined by considering time dependency of chloride transport. From the examination, the histogram of chloride contents at rebar is closer to a gamma distribution, and the mean value increases with time, while the coefficient of variance decreases with time. It was found that the probability of corrosion initiation and the time to corrosion were dependent on the time dependency of chloride transport. Time independent model predicted time to corrosion initiation of inner wall and outer wall as 8 and 12 years, respectively, while 178 and 283 years of time to corrosion was calculated by time dependent model for inner wall and outer wall, respectively. For time independent model, the probability of corrosion at 100 years of exposure for inner wall and outer wall was ranged 59.5 and 95.5%, respectively, while time dependent model indicated 2.9 and 0.2% of the probability corrosion, respectively. Finally, impact of $C_{lim}$, including values specified in current codes, on the probability of corrosion initiation and corrosion free life is discussed.

The Solvent Extraction of Univalent Cation Picrates by New Podands (새로운 포단드에 의한 피크린산 일가 양이온 염의 용매추출)

  • Jung, Jong Hwa;Cho, Sung Bae;Kim, Jineun;Kim, Jae Sang;Lee, Shim Sung
    • Analytical Science and Technology
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    • v.6 no.1
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    • pp.29-37
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    • 1993
  • Some new podands containing phenyl(B), benzyl(Bz), pyridine(Py), quinoline(Q) and naphthalene(Np) as end-groups, and oxygen(O) and sulfur(S) in ether chains as donor atoms have been synthesized. The univalent cation binding characteristics of these podands have been studied by NMR titration and solvent extraction. By NMR titration we have found that the most of podands form 1:1 complexes with $Ag^+$ ion. Especially, the substituted sulfur atoms in ether chains show the effects to enhance the stabilities. We also carried out the extractions of univalent cation picrates including alkaline metal, $Ag^+$, $Tl^+$ and $NH_4{^-}$ ions from aqueous to chloroform layer by using these podands. We found that the extractabilities of $Ag^+$ ion with the quinoline-containing podands such as, $Q_2O_4$, $Q_2O_5$ and $BQO_5$ were 86.8, 86.6 and 48.0% respectively, but the naphthalene-containing podands such as, $Np_2O_4$ and $Np_2O_5$ extracted quite small amount. Otherwise, in cases of $Bz_2O_3S_2$(89.4%), $B_2O_2S_2$(96.8%), $B_2O_3S_2$(58.9%), $Py_2O_2S_2$(58.8%), $Py_2O_3S_2$(42.1%), and $B_2O_4S$(15.0%), interestingly, $Bz_2O_3S_2$ which have sulfur atoms and benzyl groups showed the highest extraction selectivity for $Ag^+$ ion. This result seems due to not only the strong interaction of $Ag^+$ ion with sulfur donors according to the HSAB theory, but also the effective ${\pi}-{\pi}$ stacking interaction between two aromatic end-groups which is enhanced by the flexible methylene spacing group in benzyl groups instead of phenyl groups. The extraction coefficients gave the similar tendency as the extractabilities and the stabilities. From these results, it could be concluded that the predominant factor affected to extraction coefficients is the stabilities, which are strongly influenced by the structures of podands.

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