• Bulletin of the Korean Chemical Society
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• v.23 no.9
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• pp.1321-1324
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• 2002

• Bulletin of the Korean Chemical Society
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• v.15 no.5
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• pp.347-349
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• 1994

The Oguchi theory of antiferromagnetism has been modified for antiferromagnetically interacting spin-pair systems with anisotropic exchange interaction. The parallel and perpendicular susceptibilities $({\chi}_{\parallel}\;and\;{\chi}_{\perp})$ have been expressed as functions of exchange interactions $(J_z\;and\;{\gamma}=J_x/J_z)$, anisotropic molecular field parameters $({\kappa}\;and\;{\kappa}_x)$, $g_z\;and\;g_x$. In contrast to the previous theories, the parallel susceptibilities are not the same as the perpendicular susceptibilities above Neel temperature $T_N$.

• Journal of the Korean Magnetics Society
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• v.25 no.4
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• pp.106-110
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• 2015

We have studied electronic and magnetic structure of 2 kinds of diiron molecules using OpenMX method based on density functional method. The calculated density of states of diiron-2 is similar with that of diiron-4 because of equal number of 6 ligand atoms. The calculated total energy with antiferromagnetic spin configuration is lower than those of ferromagnetic configurations for both of them. The exchange interaction J of diiiron-4 between $Fe^{+3}$ atoms is one order larger than that of diiron-2, and the calculated J matches well with the experimental one. That comes from the short distance of Fe-O and the high O 2p energy levels. It derives a strong super exchange interaction. The angle of diiron-4 between Fe atoms is bigger than that of diiron-2. It also derives a strong super exchange interaction because of the ${\sigma}$-bond between Fe and O atoms.

• Journal of Advanced Marine Engineering and Technology
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• v.23 no.2
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• pp.192-200
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• 1999

This paper describes experimental investigations of helium-air exchange flow through parti-tioned opening. Such exchange flow may occur following rupture accident of stand pipe in high temperature gas cooled reactor. A test vessel with a opening on top of test cylinder is used for experiments. An estimation method of mass increment is developed and applied to measure the exchange flow rate. A technique of flow visualization by Mach-Zehnder interferometer is provided to recognize the exchange flows. Flow measurements are made with partitioned opening for parti-tion rations $H_p/H_1$ in the range 0 to 1 where $H_p$ and $H_1$ are partition length and height of the open-ing respecticely. In the case of $H_p/H_1$ of 0 flow passages of upward flow of the helium and down-ward flow of the air within the opening are unseparated (bidirectional) and the two flows interact exchange flow rate is minimum through range of the partition ratios, Two flow zones i.e. separat-ed(unidirectional)flow zone and unseparated(bidirectional) flow zone exist with increasing the partition. length, The exchange flow rate increases with increasing the separated flow zone. It is found that a maximum exchange flow rate exists at $H_p/H_1$ of 1. As a result fo comparison of the exchange flow rates by changing the partition ration the fluids interaction in the unseparated zone is found to be an important factor on the helium-air exchange flow rate.

• Membrane Journal
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• v.31 no.2
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• pp.145-152
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• 2021

While there are increasing demands on biomolecules separation, resin chromatography lacks in terms of throughput and membrane chromatography is an alternative with high binding capacity and enhanced mass transfer properties. Unlike typical membrane processing, where the performance can only be empirically assessed, understanding how mechanisms work in membrane chromatography is decisive to design biospecific processing. This short review covers three separation mechanisms, including affinity interaction modes for selectively capturing bulk molecules using biospecific sites, ion exchange modes for binding biomolecules using net charges and hydrophobic interaction modes for binding targeted, hydrophobic species. The parameters in designing membrane chromatography that should be considered operation-wise or material-wise, are also further detailed in this paper.

• Journal of the Korean Geotechnical Society
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• v.29 no.8
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• pp.65-73
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• 2013

Ground-coupled heat pump system has attracted attention as a promising renewable energy technology due to its improving energy efficiency and eco-friendly mechanism for space cooling and heating. Pipes buried in the ground play a role of direct thermal interaction between circulating fluid inside the pipe and surrounding soils in the geothermal exchange system. However, both complexities of turbulent flow coupling thermal-hydraulic phenomena and very long aspect ratio of the pipe make it difficult to model the heat exchange system directly. Energy balance for fluid flow inside the pipe was derived to model thermal-hydraulic phenomena, and one-dimensional pipe element was proposed through Galerkin formation and time integration of the equation. Developed element is combined to pre-developed FEM code for THM phenomena in porous media. Numerical results of Thermal Response Test showed that line-source model overestimates equivalent thermal conductivity of surrounding soils due to thermal interaction between adjacent pipes and finite length of the pipe. Thus, inverse analysis for the TRT simulation was conducted to present optimal transformation matrix with utmost convergence.

• Proceedings of the Korean Magnetic Resonance Society Conference
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• 2002.08a
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• pp.70-71
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• 2002

Exchange-coupled cluster of transition-metal ions are relevant to many different scientific areas, ranging from chemistry to solid-state physics, biology, material science and has been the subject of much research in recent years(1,2). Single crystal EPR spectroscopy works as a very effective tool for the measurement of J values for small exchange interactions. This makes EPR technique very suitable for detection of weak exchange coupling transmitted over long distances via extended atomic and melecular bridges. Large polyoxometallates (3) may provide ideal structural environments for the study of interactions between paramagnetic ions. The detailed nature of magnetic interaction (positive sign and magnitude of J~0.006 $cm^{-1}$ /) was clearly determined for di-copper(II) system by single crystal EPR spectroscopy (4). The single-triplet (S-T) transitions are forbidden by different symmetries of the wave functions. However, when the singlet ground state is mixed into triplet states, the S-T transitions can be allowed and observed as weak lines. These weak S-T lines are positioned symmetrically with respect to the main transitions in the distance equals to 2J from the center of the spectrum. This lines allow one to determine the J-value with very high accuracy when │J│ ＜ hv 0.32 $cm^{-1}$ /. Unfortunately, the S-T transitions in the single crystal were detected by EPR method only in a few complexes until now. We have measured single-triplet transition lines for several magnetically coupled cluster systems and determined their J values accurately. The temperature dependency of J was studied by monitoring the changes in S-T.

• Journal of the Korean Home Economics Association
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• v.28 no.3
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• pp.147-160
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• 1990

Family researchers had devoted little attention to Choice, Exchange theory by the time 1960. Being anchored by Thibaut & kelley(1959), this theory becomes one of the most widely used theoretical frameworks for family research. Waller's(1938) famous rating-dating hypothesis was intrinsically an exchange formulation. Blood and Wolfe(1960) employed the concept of rewards in their theory of family power. Farber(1964) also used the reward concept in his theory of permanent availability. Heer's(1964) specific application of its concepts to spousal power was among its earliest uses in the family. The general principle or most general proposition of the theory is that humans avoid costly behavior and seek rewarding statuses, to the end maxmize profits. This review will attempt to show that Choice, Exchange theory is applicable to the several arenas of family interaction and that it can provide an explanation for family behavior. Subjects such as mate selection, marital unstability, family cohesion, spousal power, the problems of aged, family co-unseling, and so on are included. By discussing research findings from a perspective of rewrds and costs this review will show that the application of the theory is not limited to one or two substative specialities with in the family domain. After all Choice, Exchange theory is truly general and can be productively applied to any domain of human behavior.

• Journal of Families and Better Life
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• v.24 no.3 s.81
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• pp.59-72
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• 2006

This article explores bilateralization phenomena in Korean families through intimacy and interaction with matrilineal kins. In-depth interviews were conducted with married men and women aged from their mid-30s to mid-40s. The findings indicate that the intimacy range of participants was restricted to blood-based kins. The power hypothesis was supported for male participants. Some wanted to actively contact their spouse's family members, while others did not want to be connected with the spouse's families. Interaction with wives' families was based on the exchange perspective. In contrast, a complicated mechanism existed in the intimacy and interaction of female participants. Most of them were connected with in-laws in a passive way but actively interacted with their family-of-origin. However, some female respondents did not have good relationships with their mothers. Undifferentiation between mothers and married daughters negatively influenced their relationships. Therefore, it could be concluded that bilateralization phenomena in Korean families is another kind of shackle of patrilineal norms.

• Archives of Pharmacal Research
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• v.21 no.6
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• pp.707-711
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• 1998

The (Na,K)ATPase is responsible for generating the ionic gradients and membrane potentials by the exchange of intracellular $Na^+$ for $K^+$. It has been recentl y shown that (Na,K)ATPase is involved in the exocytic pathway of basic fibroblast growth factor (bFGF), although it is not known that bFGF is secreted to the outside of cell through direct interaction with (Na,K) ATPase. To understand the role for (Na,K)ATPase in the secretary pathway of bFGF, we have sought to identify the cytoplasmic domains of the alpha1 isoform of (Na,K)ATPase interacting with bFGF by yeast two-hybrid system. We have also investigated the interaction between the alpha2 isoform of (Na,K)ATPase and bFGF to find out whether the interaction is isoform-specific. We found that none of the cytoplasmic domains of (Na,K)ATPase isoforms interacted with bFGF. The result suggests that the interaction between bFGF and (Na,K)ATPase might be indirect, thus requiring other proteins which are involved in the formation of protein complexes for the interaction, although we cannot exclude the possibility that the interaction requires the element of the whole alpha subunit structure that was not present in the isolated alpha subunit cytoplasmic domains.