• Proceedings of the KWS Conference
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• 2004.05a
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• pp.48-50
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• 2004

TLP 접합 공정에서 모재와 삽입금속 사이에서의 확산을 통하여 액상 삽입금속은 고온에서 등온으로 유지 시 등온 응고된다. D.S.Duvall은 느린 가열시 매우 빠른 속도로 가열 시 보다 낮은 온도에서 dissolution이 완료되고 응고가 발생할 것으로 예상하였다. (중략)

• Transactions of the Korean Society of Mechanical Engineers
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• v.10 no.5
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• pp.798-805
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• 1986

단열 혹은 등온 경계조건 하의 수직평판과, 선열원으로부터 형성되는 열상승류 간의 열적 상호작용을 조사형ㅆ다. 경계층 방정식은 Patankar-Spalding의 유한차분법을 사용하여 계산하였다. 단열평판의 경우에 자유 열상승류로부터 벽 경계층으로 부터의 점진적인 발달 단계를 설명하였다. 등온평판의 경우에는 평판주위에 새롭게 형성되는 열경계층에서의 열전달현상을 자세히 고찰하였다.

• KSBB Journal
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• v.21 no.5
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• pp.371-375
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• 2006

Frontal analysis(FA) and Pulsed input method(PIM) have been frequently utilized to measure isotherm of single solute, as well as non-competitive isotherms of two solutes in chromatography(1). FA and PIM were used in this study as complementary methods to measure adsorption isotherms of loxoprofen racemate in HPLC. Prior to FA and PIM experiments, measurements of loxoprofen solubility were made at hexane/ethanol=50/50, 80/20, 95/5(v/v) with acetic acid(0.5%) for adjusting pH. The last composition(95/5) of hexane/ethanol allows us to separate loxoprofen racemate into two forms(retentate, extract). PIM and FA were used to determine the isotherms of re-and ex-loxoprofen.

• Transactions of the Korean Society of Mechanical Engineers
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• v.14 no.1
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• pp.207-213
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• 1990

Natural convection heat transfer in rectangular air enclosure was studied interferometrically and numerically for the use of adiabatic and constant temperature horizontal boundary conditions. In the isothermal horizontal boundary case with the temperature difference ratio, .DELTA. $T_{v/}$.DELTA. $T_{H}$ .simeq. 1 temperature distribution in the enclosure is strongly stratified and the average Nusselt Number is higher than that of adiabatic horizontal boundary case.ase.

• Journal of the Mineralogical Society of Korea
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• v.18 no.4 s.46
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• pp.289-299
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• 2005

Annealing experiments on albite powders, thin sections, and TEM specimens have been performed utilizing an optical microscope heating stage. Sample orientations were determined by optical microscope and XRD, and then confirmed by TEM diffraction patterns. Partial melting of samples occurred at $1030^{\circ}C$-l2 hr for powder, but at $1060^{\circ}C$-12 hr for TEM specimen. It is difficult to get TEM images of albite microstructures above this temperature due to thickening and the amorphous phase of the melted part. Correlative studies between optical microscopy and TEM indicated that the $1050^{\circ}C$-12 hr annealing in ambient condition was most adequate to observe tweed microstructures in albite through TEM. In situ TEM heating experiments for direct observation of tweed microstructures in albite may require annealing at slightly higher temperatures than $1050^{\circ}C$ considering the high vacuum condition inside TEM.

• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.6
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• pp.1195-1204
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• 1992

The natural convection from upward and downward facing horizontal isothermal plate immersed in water is studied numerically. The temperature of the plate is from 0.0 .deg. C to 8.0 .deg. C and the ambient water temperature is from 1.0 .deg. C to 10.0 .deg. C. Numerical results are presented for the velocity profiles, temperature profiles, local heat transfer coefficients, and average Nusselt numbers over the entire flow fields. Flow patterns are shown in the upward and downward facing surfaces at different ambient water temperatures. For the upward facing surface, there are upflow and unsteady flow. And the regions of the ambient water temperatures which give rise to the upflow are more extensive as the temperatures of the isothermal surface become more distant from the density extremum temperature. For the downward facing surface, only the downflow region is shown. For the upward facing horizontal isothermal surface, the average Nusselt number(= N $u_{1}$$^{*}$) is 28.86(Ra)$^{0.01}$. And for the downward facing surface, the average Nusselt number(= N $u_{2}$$^{*}$) is $C_{2}$(Ra)$^{0.2}$ and the values of $C_{2}$ are enlarged in the range of 0.785 .leq. $C_{2}$ .leq. 1.250 as increasing of the temperatures of the isothermal surface.ace.ace.

• Journal of Korea Soil Environment Society
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• v.1 no.1
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• pp.81-88
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• 1996

To study the Cd adsorption in the presence of competing ions in soil-solution interphase, three soil samples from the Bt horizon were taken and analyzed for their physical and chemical properties. Adsorption of ethylene glycol monoethyl ether(EGME) and N, were determined to establish the specific surface area of the soils. We attempted to establish a qeneralizing competitive sorption isotherms for soils of entirely different composition of the solid phase, resulting in the routine use as a guidelines for the fate of reactive solute in soil profiles. Many physicochemical factors including competitive adsorption bettween solutes will affect the general adsorption phenomena as shown in a single not only on the soil:solution ratio used, but also on the surface areas of its respective soil samples. This phenomenon was attributed to competition Cd for sorption sites with Mg by different soil constituents. These adsorption isotherms are able to use as examples to demonstrate that this phenomenon can complicate the development of a standardized batch adsorption procedure as well as interpreting fate and adsorption of toxic inorganic compounds.

• Korean Journal of Food Science and Technology
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• v.15 no.4
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• pp.315-320
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• 1983

The water vapor sorption isotherms for a great variety of agricultural products were determined by using the standard salt solution technique at the temperatures of $25^{\circ},\;35^{\circ}\;and\;45^{\circ}C$. The B.E.T. monomolecular layer moisture contents were evaluated from experimental data on the sorption isotherms, and an analysis was made of the thermodynamic functions for water vapor sorption behaviors with respect to the storage stability of dehydrated foods. It may be concluded that the variation of entropy with moisture content of some agricultural products and seaweeds investigated would be a guide for the elucidation of the storage stability of dehydrated foods.

• Journal of the Korean Society of Propulsion Engineers
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• v.22 no.2
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• pp.59-65
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• 2018

We conducted an isothermal slow cook-off(ISCO) test for an aluminized explosive containing AP. The sample bulged before the run-away reaction, and therefore we were unable to obtain the ISCO data. However, these phenomena did not occur for a certain AP grade, which means that the quality of the AP exerted a significant effect on the thermal stability of the explosive formulation. In this study, we investigated the thermal stability difference between a good and bad AP grade. First, we characterized the thermal properties of all APs by Differential Scanning Calorimeter(DSC) and correlated them to the ISCO phenomena. In addition to the DSC study and ISCO test, we also investigated and calculated the SADT and self-heating rate by the ARC of the different AP qualities to interpret the thermal stability of the explosive formulation. Moreover, we investigated the impurity of the AP and a preparation method to remove the included impurity and crystallization. Finally, we implemented qualification methods to identify the quality of AP by DSC using a high-pressure crucible.

• Korean Journal of Environmental Agriculture
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• v.33 no.3
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• pp.169-177
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• 2014

BACKGROUND: The ferronickel and rapid cooling slags used in present study are industrial wastes derived from a steel factory in Korea. These slags are used as almost road construction materials after magnetic separation. However, the use of slag to remove phosphorus from wastewater is still a relatively less explored. The objective of this work was to evaluate the feasibility of ferronickel slag (FNS) and rapid cooling slag (RCS) as sorbents for phosphorus removal in wastewater. METHODS AND RESULTS: Adsorption experiments were conducted to determine the adsorption characteristics of the FNS and RCS for the phosphorus. Adsorption behaviour of the phosphorus by the FNS and RCS was evaluated using both the Freundlich and Langmuir adsorption isotherm equations. FNS and RCS were divided into two sizes as effective sizes. Effective sizes of FNS and RCS were 0.5 and 2.5 mm, respectively. The adsorption capacities (K) of the phosphorus by the FNS and RCS were in the order of RCS 0.5 (0.5105) > RCS 2.5 (0.3572) ${\gg}$ FNS 2.5 (0.0545) ${\fallingdotseq}$ FNS 0.5 (0.0400) based on Freundlich adsorption isotherm. The maximum adsorption capacities (a; mg/kg) of the phosphorus determined by the Langmuir isotherms were in the order of RCS 0.5 (3,582 mg/kg) > RCS 2.5 (2,983 mg/kg) > FNS 0.5 (320 mg/kg) ${\fallingdotseq}$ FNS 2.5 (187 mg/kg). RCS 0.5 represented the best sorbent for the adsorption of phosphorus. In the experiment, the Langmuir model showed better fit with our data than the Freundlich model. CONCLUSION: This study indicate that the use of RCS in constructed wetlands or filter beds is a promising solution for phosphorus removal via adsorption and precipitation mechanisms.