• Ocean and Polar Research
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• v.32 no.2
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• pp.145-156
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• 2010

This study investigated organic carbon fluxes in Ulleung Basin sediments, East Sea based on a chamber experiment and geochemical analyses. At depths greater than 2,000 m, Ulleung Basin sediments have high organic carbon contents (over 2.0%). Apparent sedimentation rates (ASR) calculated from excess $^{210}Pb$ activity distribution, varied from 0.036 to $0.047\;cm\;yr^{-1}$. The mass accumulation rates (MAR) calculated from porosity, grain density (GD), and ASR, ranged from 131 to $184\;g\;m^{-2}\;yr^{-1}$. These results were in agreement with sediment trap results obtained at a water depth of 2100 m. Input fluxes of organic carbon varied from 7.89 to $11.08\;gC\;m^{-2}\;yr^{-1}$ at the basin sediments, with an average of $9.56\;gC\;m^{-2}\;yr^{-1}$. Below a sediment depth of 15cm, burial fluxes of organic carbon ranged from 2.02 to $3.10\;gC\;m^{-2}\;yr^{-1}$. Within the basin sediments, regenerated fluxes of organic carbon estimated with oxygen consumption rate, varied from 6.22 to $6.90\;gC\;m^{-2}\;yr^{-1}$. However, the regenerated fluxes of organic carbon calculated by subtracting burial flux from input flux, varied from 5.87 to $7.98\;gC\;m^{-2}\;yr^{-1}$. Respectively, the proportions of the input flux, regenerated flux, and burial flux to the primary production ($233.6\;gC\;m^{-2}\;yr^{-1}$) in the Ulleung Basin were about 4.1%, 3.0%, and 1.1%. These proportions were extraordinarily higher than the average of world open ocean. Based upon these results, the Ulleung Basin might play an integral role in the deposition and removal of organic carbon.

• Journal of the Korean Ceramic Society
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• v.23 no.3
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• pp.78-86
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• 1986

single crystals of various hexagonal ferrites were grown by a flux technique. For the growing experiment platinum crucibles of size 40 cc and a horizontal siliconit tube furnace were used. Charges consisted of the flux of BaO(SrO)/$B_2O_3$ and the composition of crystals in the system of BaO $(SrO)-Fe_2O_3-ZnO$. The BaO(SrO)/$B_2O_3$ molar ratio of the flux were varied from 1 to 3. Crystals up to 12.5mm in diameter were grown by slow cooling of melts from a maximum temperature of 1, 30$0^{\circ}C$or 1, 350$0^{\circ}C$ to 95$0^{\circ}C$ or 1, 00$0^{\circ}C$ The grown crystals exhibited a tabular hexagonal habits with very well developed ba-sal planes and narrow pyramidal faces of {1011} {1012} and {0001}. For the identification of the grown crystals X-ray diffraction studies were carried out. The effects of va-riations in flux ratio flux percentage and cooling rate on the quality of the grown crystals were studied. Cry-stal habits hillocks etch steps and growth spirals were observed by optical microscope. Magnetic properties of single crystals were measured.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.6 no.1
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• pp.44-55
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• 1996

Emerald (3BeO{\cdot}Al$_{2}$O_{3}{\cdot}6SiO_2 : Cr^{3+}$) single crystals were grown by flux method of $Li_2O-MoO_3 - V_2O_5$ system. The composition of starting materials were 1, 3, 5 mole ratio of $MoO_3 - V_2O_5/$Li_2O$, 20 - 15% of emerald content to flux composition and 1% of $Cr_2O_3$ colordopant to emerald composition. After mixing those were melted at $1100^{\circ}C$ in Pt crucible of electric furnace. Single crystal growth was cooled down slowly rate of $3^{\circ}C$/hr from $1100^{\circ}C$ to $650^{\circ}C$, for the cooling period it was controlled and prevented the nucleation of microcrystallite from variation of each thermal fluctuation range. Specially it has been obtained plenty of large emerald single crystal when thermal fluctuation was treated for cooling period at $1050 ~ 950^{\circ}C$, in 3 mole ratio of $V_2O_5 - MoO_3/Li_2O$ flux. Emerald single crystal growing effect and $Cr_{+3}$ ion of substitutional solid solution effect for $Al_{+3}$ ion was good than mole ratio of 5. Emerald single crystals were c (0001) hexagonal rystal face of preferencial direction and m (1010) post side. Emerald was hexagonal columnar greenish transparent and 2.65 ~ 2.66 of specific gravity.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.30 no.1
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• pp.37-41
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• 2017

In this paper, the fault current limiting characteristics of the flux-lock type SFCL (superconducting fault current limiter) using magnetic application circuit were analyzed. The flux-lock type SFCL has the structure to install the magnetic application circuit, which can increase the resistance of HTSC ($high-T_C$ superconducting element comprising) the SFCL. To analyze the fault current limiting effect of the flux-lock type SFCL through the magnetic flux application circuit, the flux-lock type SFCL either with the magnetic flux circuit or without the magnetic flux circuit was constructed and the fault current limiting characteristics of the SFCL were compared each other through the short-circuit tests.

• Progress in Superconductivity
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• v.9 no.1
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• pp.11-17
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• 2007

Magnetization studies have been carried out on $MgB_2$ polycrystalline samples in the temperature range of 5 - 44 K and in the magnetic field up to 7 Tesla. The critical current density was calculated from hysteresis loops using the Bean's critical state model, and the highest value of $J_c$ at 20 K was $2.7{\times}10^5\;A/cm^2$ at 2 Tesla. The hysteresis loops were carefully examined to determine the temperature and magnetic field range where flux jumps appeared. The first jump occurred typically at 1 Tesla. Due to the strong pinning, we observed the presence of flux jump below H = 1 Tesla at temperature below 30 K.

• Journal of Advanced Marine Engineering and Technology
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• v.26 no.3
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• pp.320-327
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• 2002

An experimental study of heat transfer from hot flat surface to water sprays was conducted in high temperature region. Heat transfer measurements for hot flat surface were made by 4 sheathed C-A thermocouples. Droplets volume flux were also measured-independently at a position in spray field. The test conditions included variations in droplets volume flux, subcooling of cooling water of $1.565\times10^{-3} to 14.089\times10^{-3}m^3/m^2s and 80 to $20^{\circ}C$ respectively. The effects of inclination angle on heat transfer were investigated and changes in inclination angle of hot flat surface affected heat transfer coefficients of high temperature region.

• Journal of the Korean Ceramic Society
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• v.29 no.6
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• pp.463-470
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• 1992

Corundum single crystals were grown in cryolite flux with the composition of Na3AlF6:Al2O3=80:20 wt%. This mixture was melted at 115$0^{\circ}C$, followed by slow cooling at a rate of 2$^{\circ}C$/hr to 96$0^{\circ}C$. And by adding of La2O3 to the flux, the change of crystal forms were observed. Crystal forms of corundum grown in cryolite flux had the habits of hexagonal plate which consist of well developed {0001} face and small {101} face. As La2O3 was added and its content was increased, {223} and {110} faces were developed, and crystal habits of equidimensional forms changed into hexagonal prism form. In a charge of 8 mole% B2O3, Al2O3:La2O3=15:1, transparent corundum single crystals of equent form were grown. As the content of B2O3 was increased, twineed crystals which have twin law of 2-fold parallel to [0001], and composition plane of (110) were grown.

• Journal of Pharmaceutical Investigation
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• v.41 no.6
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• pp.337-345
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• 2011

The objective of this work is to investigate the effect of chemical enhancer and current on the flux of donepezil hydrochloride (DH) through skin. Ethanol and N-methyl pyrrolidone (NMP) were used as chemical enhancers in combination with iontophoresis. We also have studied the effect of pH on flux and evaluated the role of electroosmosis. In vitro flux study was performed at $33^{\circ}C$, using side-by-side diffusion cell and full thickness hairless mouse skin. Passive flux of DH without enhancer was very small. As the concentration of enhancer increased, passive flux increased. After current application, flux increased markedly and the time to reach maximum decreased. Without enhancer, maximum flux was about 50 fold larger than that obtained without current. These results indicate that electromigration is playing a major role for the transport. As the enhancer concentration increased, flux also increased. NMP and ethanol increased not only the passive delivery, but also the iontophoretic delivery. Flux results indicate that ethanol has better ability than NMP in enhancing the transport of DH. The magnitudes of increase in flux by these enhancers indicate that there is a large synergistic effect in flux enhancement. Flux results from pH study showed that electroosmotic flow is reversed at low pH and the flux is hindered. These results provided some information on the flux enhancing ability of ethanol and NMP in combination with iontophoresis. The data also provided some mechanistic insights into the role of electromigration and electroosmosis on flux through skin.

• Journal of Advanced Marine Engineering and Technology
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• v.22 no.6
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• pp.880-887
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• 1998

In order to study heat transfer characteristics of spray cooling for the purpose of uniform and soft cooling of high temperature surface a series of experiments for a hot horizontal copper flat plate was performed by downflow spray water using flat spray nozzle. Cooling curves were mea-sured under the various experimental conditions of flow rates and temperatures of cooling water Surface temperature surface heat fluxes and heat transfer coefficients of horizontal upward-facing flat surface were calculated with cooling curves measured at each radial positions near the cooling surface by TDMA method. Generally heat transfer characteristics for spray cooling is simi-lar to boiling phenomenon of pool boiling. The minimum heat flux(MHF) appear at the surface temperature of about ${\Delta}Tsat=250^{\circ}C$ and the critical heat flux(CHF) appear at about ${\Delta}Tsat=250^{\circ}C$.

• Proceedings of the KIPE Conference
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• 2003.07b
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• pp.828-831
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• 2003

This paper presents a novel design technique and characteristic analysis of Magnet for dual air-gap axial-flux type permanent-magnet synchronous generator. The process of magnet design is applied to the motor design and steady state analysis considering output voltage waveforms and magnetic flux waveforms. Design and construction of an axial-flux permanent-magnet generator with power output at 60 [Hz], 300[r/min] is introduced. Finite-element (FE) method is applied to analyze magnet shape characteristics. The results of FE analysis show generator is feasible for use with dual air-gap axial-flux permanent- magnet synchronous generator.