• Journal of the Korean Chemical Society
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• v.24 no.2
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• pp.139-145
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• 1980

High spin iron(II) complexes of 1,4,8,11-tetraazacyclotetradecane (cyclam), a macrocyclic ligand, and 1,5,8,12-tetraazadodecane (3,2,3-tet), a noncyclic ligand, have been prepared. The reaction of low spin $[Fe(cyclam)(CH_3CN)_2](ClO_4)_2$ with chloride ion in methanol produces high-spin $[Fe(cyclam)Cl]ClO_4$. Although $[Fe(cyclam)(CH_3CN)_2](ClO_4)_2$ is low spin, $[Fe(3,2,3-tet)(CH_3CN)_2](ClO_4)_2$ isolated in the present study is high spin. This difference is explained in terms of the smaller constrictive effect exerted by the noncyclic ligand than the cyclic ligand. The isolation of $[Fe(cyclam)Cl]ClO_4$ provides evidences against the current view that the presence of either unsaturation or substituents on the macrocyclic ligands is necessary for the successful preparation of high spin five-coordinate iron (II) complexes. Reactions of $[Fe(cyclam)Cl]ClO_4\;and\;[Fe(3,2,3-tet)(CH_3CN)_2](ClO_4)_2$ with carbon monoxide yield low spin six-coordinate $[Fe(cyclam)Cl(CO)]ClO_4\;and\;[Fe(3.2,3-tet)(CH_3CN)(CO)](ClO_4)_2$, respectively.

• Journal of the Korean Society for Precision Engineering
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• v.22 no.6 s.171
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• pp.144-151
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• 2005

Spin coater is regarded as a major module rotating at high speed to be used build up polymer resin thin film layer fur bonding process of GaAs wafer. This module is consisted of spin unit for spreading uniformly, align device, resin spreading nozzle and et. al. Specially, spin unit which is a component of module can cause to vibrate and finally affect to the uniformity of polymer resin film layer. For the stability prediction of rotation velocity and uniformity of polymer resin film layer, it is very important to understand the dynamic characteristics of assembled spin coater module and the dynamic response mode resulted from rotation behavior of spin chuck. In this paper, stress concentration mode and the deformed shape of spin chuck generated due to angular acceleration process are presented using analytical method for evaluation of structural safety according to the revolution speed variation of spin unit. And also, deformation form of GaAs wafer due to dynamic behavior of spin chuck is presented fur the comparison of former simulated results.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.336-336
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• 2016

We have investigated magneto-transport properties in a MoS2 lateral spin-valve structures for different ferromagnetic CoFe electrode shapes and MoS2 channel lengths. For these devices, high quality and large-scale MoS2 thin films were synthesized through sulfurization of epitaxial MoO3 films and these sulfurized-MoO3 thin films properties are in good agreements with measurements on exfoliated MoS2 film. Magneto-transport measurements show a clear rectangular magnetoresistance signal of 0.16% and a spin polarization of 0.00012%. By using the one-dimensional spin diffusion equation, we extracted the spin diffusion length and coefficient, finding them to be 12 nm and $1.44{\times}10-3cm2/s$, respectively. These small values of magnetoresistance and spin polarization could be enhanced by appeasement of conductivity mismatch between the ferromagnet and semiconductor interface.

• Journal of Magnetics
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• v.5 no.2
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• pp.44-49
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• 2000

Computer simulation of sensing current effects on the magnetic and magnetoresistance properties of a crossed spin-valve head is carried out. The spin-valve head has the following layer structure: Ta (8.0 nm)/NiMn (25 nm)/NiFe (2.5 nm)/Cu (3.0 nm)/NiFe (5.5 nm)/Ta (3.0 nm), and it is 1500 nm long and 600 nm wide. Even with a high pinning field of 300 Oe and a high hard-biased field of 50 Oe, the ideal crossed spin-valve structure, which is essential to the symmetry of the output signal and hence high density recording, is not realized mainly due to large interlayer magnetostatic interactions. This problem is solved by applying a suitable magnitude of sensing currents along the length direction generating magnetic fields in the width direction. The ideal spin-valve head is expected to show good symmetry of the output signal. This has not been shown explicitly in the present simulation, however, The reason for this is possibly related to the simple assumption used in this calculation that each magnetic layer consists of a single domain.

• Journal of Microbiology and Biotechnology
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• v.12 no.3
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• pp.406-410
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• 2002

A new spin filter consisting of $50{\mu}m$ (nominal pore size) depth fitters rolled on a stainless steel grid was developed, using Saccharomyces cerevisiae as a model suspension cell to evaluate the spin filter performance. In a 1.8-1 fermentor with a rotation speed of 300 rpm and perfusion rate of 4 ml/min, a cell concentration of 49 g/l and ethanol concentration of 45 g/l from 100 g/l glucose could be obtained in a perfusion culture. The major mechanisms for cell separation used by the large-pore spin filter appeared to be centrifugal force and pivotal movement of the cells in the spin filter.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.10 no.6
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• pp.146-151
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• 2011

Wax spin coating is a part of several wafer handling processes in the silicon wafer polishing station. It is important to ensure the wax layer free of contamination to achieve the high degree of planarization on wafers after wafer polishing. Three-dimensional air flow characteristics in a wax spin coater are numerically investigated using computational fluid dynamics techniques. When the bottom of the wax spin coater is closed, there exists a significant recirculation zone over the rotating ceramic block. This recirculation zone can be the source of wax layer contamination at any rotational speed and should be avoided to maintain high wafer polishing quality. Thus, four air suction ducts are installed at the bottom of the wax spin coater in order to control the air flow pattern over the ceramic block. Present computational results show that the air suction from the bottom is quite an effective method to remove or minimize the recirculation zone over the ceramic block and the wax coating layer.

• Proceeding of EDISON Challenge
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• 2014.03a
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• pp.430-433
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• 2014

Perovskite 구조를 가진 코발트 산화물 $SrCoO_3$와 Brownmillerite 구조인 $SrCoO_{2.5}$의 electronic structure를 제1원리 계산을 통해 분석하였다. 이들의 magnetic structure를 계산하여 실험을 통해 알려진 값과 비교하였고, 각 구조에서 코발트 이온이 갖는 spin state를 확인할 수 있었다. 코발트 이온은 $SrCoO_3$에서 intermediate spin state(IS)를, $SrCoO_{2.5}$에서는 high spin state(HS)를 갖는데 이것이 lattice constant의 차이에 의한 것인지, 아니라면 차이의 원인은 무엇인지 density of state를 분석함으로써 알아보았다.

• Proceedings of the Microbiological Society of Korea Conference
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• 2004.05a
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• pp.141-146
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• 2004

SPIN90 was identified to farm molecular complex with $\betaPIX$, WASP and Nck. This complex shows that SPIN90 interacts with Nck in a manner dependent upon cell adhesion to extracellular matrix, but $SPIN90{\cdot}{\beta}PIX{\cdot}WASP$ complex was stable even in suspended cells. This suggests that SPIN90 serves as an adaptor molecule to recruit other proteins to Nck at focal adhesions. SPIN90 was phosphorylated by ERK1, which was, itself, activated by cell adhesion and platelet-derived growth factor. Such phosphorylation of SPIN90 likely promotes the interaction of the $SPIN90{\cdot}{\beta}PIX{\cdot}WASP$ complex and Nck. It thus appears that the interaction of the $SPIN90{\cdot}{\beta}PIX{\cdot}WASP$ complex with Nck is crucial for stable cell adhesion and can be dynamically modulated by SPIN90 phosphorylation that is dependent on cell adhesion and ERX activation. SPIN90 directly binds syndapin I, syndapin isoform II-1 and II-s via its PRD region in vitro, in vivo and also associates with endocytosis core components such as clathrin and dynamin. In neuron and fibroblast, SPIN90 colocalizes with syndapins as puntate form, consistent with a role for SPIN90 in clathrin-mediated endocytosis pathway. Overexpression of SPIN90 N-term inhibits receptor-mediated endocytosis. Interestingly, SPIN90 PRD, binding interface of syndapin, significantly blocks internalization of transferrin, demonstrating SPIN90 involvement in endocytosis in vivo by interacting syndapin. Depletion of endogenous SPIN90 by introducing $\alpha-SPIN90$ also blocks receptor-mediated endocytosis. Actin polymerization could generate farce facilitating the pinch-out event in endocytosis, detach newly formed endocytic vesicle from the plasma membrane or push out them via the cytosol on actin tails. Here we found that SPIN90 localizes to high actin turn over cortical area, actin-membrane interface and membrane ruffle in PDGF treated cells. Overexpression of SPIN90 has an effect on cortical actin rearrangement as filopodia induction and it is mediated by the Arp2/3 complex at cell periphery. Consistent with a role in actin organization, CFP-SPIN90 present in actin comet tail generated by PIP5 $kinase\gamma$ overexpression. Therefore this study suggests that SPIN90 is functional linker between endocytosis and actin cytoskeleton.

• Korean Journal of Applied Biomechanics
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• v.13 no.3
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• pp.117-131
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• 2003

This study simulated the range of golf ball with different projection angles using a drive swing condition. For the simulation purpose, the differential equation of dynamics was induced by using Bernoulli's principle and average back spin frequency, instant velocity, and dimple of golf ball from amateur group, professional group, and Tiger Woods were chosen as the initial condition. The study result indicated that lift coefficient($C_{lift}$) relative to drag coefficient ($C_d$), 0.3 of differential equation was applied differently in terms of back spin Sequency, and when $C_{lift}$ was 0.4 for amateur, 0.5 for professional, and 0.7 for Tiger Woods the projection ranges of ball were closely matched with initial condition. With selected $C_{lift}$ and back spin frequency of initial condition, the ranges with different projection angle was measured as 193m ($13-17^{\circ}$) for amateur, 240m ($9-13^{\circ}$), professional and 273m ($9^{\circ}$)Tiger Woods, respectively. For the range in terms of back spin frequency and projection angle, the amateur group indicated relatively high spin frequency (70 RPS) and showed the maximal range (195m) with $13^{\circ}$ of projection angle. The tendency of longer range with higher projection angle was also found under the different conditions of spin frequency in this group. The professional group showed their maximal range (245m) with conditions of 60RPS of spin frequency and $9^{\circ}$ of projection angle. Their range was decreased dramatically when the spin frequency was reduced to 40-50 RPS. For Tiger Woods, the maximal range was found with 40RPS of spin frequency and the range was decreased notably when the spin frequency was above 40RPS.

• The Bulletin of The Korean Astronomical Society
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• v.40 no.1
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• pp.89.1-89.1
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• 2015

Period changes found in the 10 years CCD BVR photometry data (2005 - 2014) of the Intermediate Polar MU Cam will be discussed. The timings of extrema of the data are determined and the new ephemeris for the spin period and orbital period have been calculated by using multi-periodic approximation as follows: BJD(orb)=2454085.46(19)+0.19664 $10(26){\cdot}E$ and BJD(spin)=2454085.50725(91)+0.013740942(13) ${\cdot}$ $E-1.51(10){\times}10^{-12}{\cdot}E^2$. The O-C diagram shows an increasing of the spin period as $P=-2.20(14){\cdot}10^{-12}s/s$. It is also found in MU Cam that the white dwarf's rotation seems to be switched from a state of spin-down to spin-up by the white dwarf's equilibrium spin period in 2005.