• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11b
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• pp.101-103
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• 2001

Suspension effect has been studied by using superconductor of BiPbSrCaCuO ceramics containing $Ag_{2}O$ It has been cleared that $Ag_{2}O$ acts as pinning center which plays an important role to the suspension effect. Magnetic repulsive force which affects a superconductor located in magnetic flux from toroidal magnet has been investigated. It has been concluded that the suspension effect arises from the interaction between the pinning effect and the diamagnetic effect.

• Journal of the Korean Ceramic Society
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• v.22 no.6
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• pp.58-70
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• 1985

The bond strength of metal to ceramic sealing in Mo-Mn metallizing was investigated by examining the effects of flux composition in alumina ceramics particle size of molybdenum metal powder wet hydrogen atmosphere and temperature in metallizing. The maximum bond strength was obtained when the glass phase filled almost all the microstructural cavities around the interfacial area with few micropores. Such a favorable microstrcutre waas formed and maximum bond strength was observed between 130$0^{\circ}C$. Also the metal to ceramic bond strength was increased using finer molybdenum metal powder than coarse powder. When content of $SiO_2$ in the flux of alumina ceramics was constant metal to ceramic bond strength was improved with increasing the ratio of CaO to MgO in the flux.

• The Korean Journal of Physiology
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• v.20 no.2
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• pp.175-183
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• 1986

Since it was proposed that vanadate may be an ‘ideal endogenous regulator of the $Na^+,\;K^+-ATPase$ activity (Cantley et at, 1979), vanadate has been a subject of intensive research and a variety of its physiological effects have been described (Nechay, 1984). In isolated guinea pig heart muscle vanadate shows a positive inotropic effect on ventricular muscle, while it induces a negative inotropic effect on atrial muscle. But its underlying mechanism has not been elucidated so far. Therefore, in this study the flux rates of calcium ion into and from guinea pig heart muscle were measured to throw some light on the underlying mechanism, because those rates have been known to be closely related to the cardiac contractility and the results are summarized as follows: 1) Calcium efflux rates from the intracellular $Ca^{++}$ pool (compartment 4) of both guinea pig left atrium and right ventricle were significantly reduced by vanadate and their pool sizes were significantly increased by vanadate. 2) The magnitude of calcium influx into left atrium was reduced by vanadate, While the magnitude of calcium influx into right ventricle was not affected by vanadate. From these results, it may be concluded that the positive inotropic effect of vanadate on the ventricular muscle was due to a reduced efflux rate of calcium ion and its negative inotropic effect on atrial muscle was resulted from a reduced influx of calcium ion.

• Resources Recycling
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• v.6 no.1
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• pp.5-10
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• 1997

The aluminum was recovered from the middle size (Q1.0-12.0 mm) aluminum drosses using NaCl and KC1 mixuture as a basic salt flux. The maximum aluminum recovery was about 76.9% when 40% basic salt flux was added to aluminum dross at 850$^{\circ}$C for two hours. Also, aluminum remvery increased with increasing fluoride (1%-5%) addition to basic salt flux. But, there was no considerable effect due ta the increasing of viscosity when the fluorides were added over 5%, respectively. E s p d y , the most aluminum recovery was about 83.5% when 5% cryolite was added to 40% basic salt flux.

• Proceedings of the Korean Biophysical Society Conference
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• 2003.06a
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• pp.30-30
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• 2003

Without a definitive resolution of stoichiometry of cardiac Na$^{+}$-Ca$^{2+}$exchange (NCX), we cannot proceed to any quantitative analysis of exchange function as well as cardiac excitation-contraction coupling. The stoichiometry of cardiac NCX, however, is presently in doubt because reversal potentials determined by various groups range between those expected for a 3-to-1 and a 4-to-1 flux coupling. For a new perspective on this problem, we have used ion-selective microelectrodes to quantify directly exchanger-mediated fluxes of $Ca^{2+}$and Na$^{+}$in giant membrane patches. $Ca^{2+}$- and Na$^{+}$-selective microelectrodes, fabricated from quartz capillaries, are placed inside of the patch pipettes to detect extracellular ion transients associated with exchange activity. Ion changes are monitored at various distances from the membrane, and the absolute ion fluxes through NCX are determined via simulations of ion diffusion and compared with standard ion fluxes (Ca$^{2+}$ fluxes mediated by $Ca^{2+}$ ionophore, and Na$^{+}$ fluxes through gramicidin channels and Na$^{+}$/K$^{+}$pumps). Both guinea pig myocytes and NCX1-expressing BHK cells were employed, and for both systems the calculated stoichiometries for inward and outward exchange currents range between 3.2- and 3.4-to-1. The coupling ratios do not change significantly when currents are varied by changing cytoplasmic [Ca$^{2+}$] or by adding cytoplasmic Na$^{+}$. The exchanger reversal potentials, measured in both systems under several ionic conditions, range from 3.1- to 3.3-to-1. Taken together, a clear discrepancy from a NCX stoichiometry of 3-to-1 was obtained. Further definitive experiments are required to acquire a fixed number, and the present working hypothesis is that NCX current has an extra current via ‘conduction mode’.ent via ‘conduction mode’.

• Journal of Conservation Science
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• v.20
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• pp.105-117
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• 2007

This study is examined the beads excavated in the Sacheon Neukdo ruins to investigate the features of archaeological chemistry and to compare those of the same type of beads excavated within the Gyeongsang-do area by means of scientific analysis. The samples have been observed the micro-structures by an optical microscope and SEM and confirmed the physical property by density measurement. Chemical property have been analyzed main components such as flux, stabilizers, and colorants by SEM-EDS. Besides, XRD was used to identified the characteristic materials of beads. The white opaque beads, which was initially estimated as sea-shell beads, confirm as amorphous silica material. The glass beads, which are blue type as a result of compositional analysis, it is revealed potash glass group and LCA(Low-CaO, $Al_2O_3$) system. gB ones are revealed only in LCA-A(LCA-CaO<$Al_2O_3$), while purple blue ones in LCA-B(LCA-CaO>$Al_2O_3$).

• Progress in Superconductivity
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• v.5 no.1
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• pp.9-12
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• 2003

We observed the splitting of the fluxon-flow branches in the current-voltage characteristics of serially stacked intrinsic Josephson junctions (IJJs) formed in $Bi_2$$Sr_2$$CaCu_2$$O_{ 8＋x}$ single crystals in the long-junction limit. Stacks of IJJs were sandwiched between two Au electrodes deposited on the top and the bottom of the stack using the ‘double-side cleaving technique’. In all the samples studied, the branch splitting started occurring for a dense fluxon configuration around 2 T and became more distinct in a higher magnetic field range. This observation can be explained in terms of switching between different Josephson fluxon modes in resonance with the collective plasma oscillations induced by both inductive and capacitive coupling between stacked IJJs. This is the first detailed and quantitative identification of the coherent flux-flow modes in stacked..

• Journal of The Korean Astronomical Society
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• v.21 no.1
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• pp.79-95
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• 1988

To examine relations between stellar activity and rotation we estimated parameters of stellar activity such as $R'_{HK}$, $R'_{MgII}$, $R'_{CII}$, $R'_{CIV}$ and $R'_{X-ray}$ from the published data which measure the activity levels of stellar chromospheres, transition regions and coronae. In the present study we considered only the main sequence stars in an attempt to minimize the influence of other stellar parameters such as radius, age and stellar convection on stellar activity since they are also known to affect the magnetic field generation. In the present analysis we selected only those stars that satisfy the following conditions: (1) flux measurements are available together with Ca II fluxes and (2) rotation periods are determined by Ca II observations. We derived relations between the ${\bar{R}}ossby$ number $R_o$ and stellar activity $R'_{HK}$, $R'_{MgII}$, $R'_{CII}$, $R'_{CIV}$ and $R'_{X-ray}$ and assessed the relations by plotting $R'_{HK}$, $R'_{MgII}$ and $R'_{X-ray}$ against rotation period $P_{rot}$ for comparison with observations. From the comparison it is found that as far as the rotation-activity relation is concerned, (1) normalized surface flux $R'_{HK}$ is better than the surface flux $F'_{HK}$, in the sense that $R'_{HK}$ differentiates the color dependence better and (2) $R'_{HK}$ defined by Rutten (1984) describes the observations notably better than $R'_{HK}$ of Noyes et al. (1984).

• Membrane and Water Treatment
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• v.2 no.4
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• pp.239-250
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• 2011

A photovoltaic powered ultrafiltration and reverse osmosis system was tested with a number of natural groundwaters in Australia. The objective of this study was to compare system performance at six remote field locations by assessing the impact of water composition and fluctuating energy on inorganic contaminant removal using a BW30-4040 membrane. Solar irradiance directly affected pressure and flow. Groundwater characteristics (including TDS, salts, heavy metals, and pH), impacted other performance parameters such as retention, specific energy consumption and flux. During continual system operation, retention of ions such as $Ca^{2+}$ and $Mg^{2+}$ was high (> 95%) with each groundwater which can be attributed to steric exclusion. The retention of smaller ions such as $NO_3{^-}$ was affected by weather conditions and groundwater composition, as convection/diffusion dominate retention. When solar irradiance was insufficient or fluctuations too great for system operation, performance deteriorated and retention dropped significantly (< 30% at Ti Tree). Groundwater pH affected flux and retention of smaller ions ($NO_3{^-}$ and $F^-$) because charge repulsion increases with pH. The results highlight variations in system performance (ion retention, flux, specific energy consumption) with real solar irradiance, groundwater composition, and pH conditions.

• 한국초전도학회:학술대회논문집
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• v.14
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• pp.7-7
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• 2004