• Journal of Korean Society of Steel Construction
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• v.22 no.4
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• pp.305-312
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• 2010

The objective of this paper is to examine the structural performance of steel moment-resisting frames on the various connection details of Seismic Wide-flanged Beam-to-Rectangular Steel Tube Column connections. Although compared to an H-shaped steel tube, a rectangular steel tube has many advantages and is more efficient, its application is limited due to the lack of experience in using it and the connection details. Existing steel moment connections using the rectangular steel tube are mainly used through plate diaphragms. The processing of construction of the rectangular steel tube is so complicated that it is hard to apply it in the field. In this study, the structural performance and the earthquake capacity of the connection details that do not cut the rectangular steel tube column were investigated. A comparative analysis of the strength, rigidity, and energy absorption capacity of the welded connection details using an end-plate and a haunch was also performed.

• Analytical Science and Technology
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• v.8 no.2
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• pp.117-124
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• 1995

To Purify hemoproteins showing from 218nm absorbance, crude liver extract of human with hepatocirrhosis was treated with Triton N-101. Hemoproteins were purified by modification of Mohamed's method. This crude extract was applied to Octyl-Sepharose CL-4B column and the step elution was performed with 0.06% Lubrol PX and 0.25% Lubrol PX. The absorption of effluents were examined at 418nm and two peaks were appeared(Fig. 2). Hemoproteins were purified from Hyydroxyapatite and DEAE-Sephadex A-25 columns which the first peak was applied to(Fig. 3, 4). In death with suddenly, purified hemoproteins with 62 and 45kDa were obtained from 12.5% SDS-PAGE. In death with hepatocirrhosis, purified hemoprotein with 54kDa was obtainded from 12.5% SDS-PAGE(Fig. 5). Cytochrome P450 was purified to a specific content of 20.8nmol/mg protein with a recovery of about 4.1%. Absorbance maximum of these hemoproteins were 446nm at UV spectruum(Fig. 6).

• Journal of Korean Society of Steel Construction
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• v.12 no.4 s.47
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• pp.387-395
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• 2000

The purpose of this research is to evaluate the capacity of strength and plastic deformation of those members, and provide experimental data on the seismic behavior of these members as a basis for developing guidelines for designing seismically resistant concrete-filled steel tubular columns. Eighteen cantilever-type specimens were tested under constant axial load and cyclically lateral load as models of bottom columns in high-rise building. The parameters studied in the test program included, are width-thickness ratio of steel tube, slenderness ratio (Lo/D) and axial force ratio. From the test results, the effects of parameters on the strength, the deformation capacity, energy absorption capacity are discussed. The specimen flexural capacity under combined axial and lateral loading was found to be almost accurately predicted by criteria AIJ and AISC-LRFD providing conservative results. Therefore KSSC for encased composite column can be applied to the concrete filled column if composite section and elastic modulus are modified according to AIJ and AISC-LRFD. Finally, the proposed flexural capacity considering confinement effects is a food agreement on the tests results.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.4
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• pp.732-738
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• 2001

This study was attempted to isolate and identify the anticancer compounds from Eucommia ulmoides leaves using a human colon cancer cell line HCT-116. The petroleum ether extracts with anticancer activity was chromatographed on silica gel TLC and finally anticancer compounds was purified by HPLC. Their chemical structures were roughly elucidate by UV-VIS absorption spectral data HPLC elution pattern and FAM/MS spectroscopy. From this study these compounds were suspected to be pheophytin a formed by the removal of $Mg^{2+}$ from chlorophyll a and pyropheophytina formed by the removal of acetate group from pheophytin a respectively. To confirm the anticancer effects against HCT-116 cancer cell petroleum ether extract fractions of column chromatography and fractions separated on TLC were tested. All samples tested including the extract of petroleum ether fractions of column chromatograph and three bands (0.13,0.19,0.25) of TLC appeared to inhibit the growth of HCT-116 cancer cell however especially 0.19 and 0.25 fractions separated on TLC plate revealed the strongest effect. These results suggest that chlorophyll derivatives in Eucommia ulmoides may be potential anticancer agents against a human colon cancer cell HCT-116.

• Journal of the Korean Association of Geographic Information Studies
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• v.19 no.2
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• pp.107-116
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• 2016

Airborne or spaceborne remote sensing can increase the efficiency of seabed material surveys compared with field surveying using a vessel. For the same seabed material, the optical remote sensing image shows variation in the reflectance depending on the water depth, which is due to the absorption and scattering by the water column. This study suggests a correction procedure to use the hyperspectral image for seabed material analysis. The study is conducted in the coastal area from Sacheonjin Port to Gyungpo Beach in Gangwon-do. The hyperspectral image is acquired using the CASI-1500 sensor. The diffuse attenuation coefficient is estimated for each band through regression models between the water reflectance and depth. Then, the coefficient is applied to each band of the image. As a result, the completely corrected image can be interpreted for a deeper area, although the interpretable area is very shallow without water column correction. Additionally, the water column corrected image shows decreased variation of reflectance with various water depths.

• Journal of Korean Society of Steel Construction
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• v.15 no.2
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• pp.207-217
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• 2003

The Concrete Filled Steel Tube (M) Column has excellent structural capacities that are in accordance with the interaction effect between the steel tube and concrete. CFT structure has been focussed on a struc tural system for high-rise buildings. The purpose of this study is to evaluate the strength and deformation capacities of CFT columns that are subject to constant axial and cyclic lateral load. The test parameters are diameters to the thickness ratio of the steel tube, axial load ratios, and the shapes of the tube. Total eighteen specimens were fabricated to clarify the energy absorption capacity of the CFT columns. Experimental results were summarized for their ultimate strengths and deformation capacities.

• Applied Biological Chemistry
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• v.41 no.8
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• pp.595-599
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• 1998

An analytical method was developed to determine tricyclazole residues in rice grain, straw, and soil using high-performance liquid chromatography (HPLC) with ultraviolet absorption detection. Tricyclazole was extracted with methanol from moist rice grain, straw, and soil samples. n-Hexane washing was employed to remove nonpolar co-extractives during liquid-liquid partition. Tricyclazole was then extracted with dichloromethane from alkaline aqueous phase, while acidic interferences remained in the phase. Dichloromethane extract was further purified by silica gel column chromatography prior to HPLC determination. Reverse-phase HPLC using an octadecylsilyl column was successfully applied to separate and quantitate the tricyclazole residue in sample extracts monitored at ${\lambda}_{max}$ 225nm. Recoveries from fortified samples averaged $95.5{\pm}3.0%\;(n=6),\;87.5{\pm}20.%\;(n=6),\;and\;84.3{\pm}2.8%$ (n=12) for rice grain, straw, and soil, respectively. Detection limit of the method was 0.02 mg/kg for rice grain and soil samples while 0.05 mg/kg for rice straw samples. The proposed method was reproducible and sensitive enough to evaluate the safety of tricyclazole residues in rice grain, straw, and soil.

• KIEAE Journal
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• v.8 no.3
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• pp.69-76
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• 2008

This is an experimental study on the maximum load value and structural behavior of reinforced concrete columns containing shells as a substitute fine aggregate of concrete, through making reinforced concrete test columns with shells. In this study, the main factors consist of the grain sizes and the percentage of substitution of shells to fine aggregate in two kinds of water cement ratio. The results of the study showed as followed. The maximum load value decreased with increased the rate of substitution about shells and as the grain size of shells became smaller, the load values of them were somewhat changed higher but it is important that we must consider absorption rate of shells sufficiently. If we have a proper water cement ratio in column productions containing the shells, we can meet the requirement of the percentage of substitution until 30%. The deflection and deformation properties of reinforced concrete columns with shells represented typical curves like that of normal reinforced concrete. But as the failture types, they are able to make some change without being out of the fundamental graph forms. After the analyzing structural behaviors and the properties of reinforced concrete test columns containing shells, the most excellent grain size of shells represented 3.0mm and less with taking uniformly, and the percentage of practicable substitution of them to fine aggregate was about 30%.

• Korean Journal of Environmental Agriculture
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• v.29 no.3
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• pp.247-256
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• 2010

A high-performance liquid chromatographic (HPLC) method was developed to determine buprofezin residues in hulled rice and fruits. The buprofezin residue was extracted with acetone and the extract was stepwise purified by liquid-liquid partition and Florisil column chromatography. For rice samples, acetonitrile/n-hexane partition was additionally employed to remove nonpolar lipids. Reversed phase HPLC using an octadecylsilyl column was successfully applied to separate buprofezin from sample co-extractives, as detected by ultraviolet absorption at 250 nm. Recovery experiment at the limit of quantitation validated that the proposed method could evidently determine the buprofezin residue at the level of 0.02 mg/kg. Mean recoveries from hulled rice, apple, pear, and persimmon samples fortified at three tenfold levels were in the range of 80.8~85.2%, 89.1~98.4%, 88.8~95.7% and 90.8~96.2%, respectively. Relative standard deviations of the analytical method were all less than 5%, irrespective of sample types. A selected-ion monitoring LC/mass spectrometry with positive electrospray ionization was also provided to sensitively confirm the suspected residue.

• Journal of Korean Society of Steel Construction
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• v.12 no.4 s.47
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• pp.445-455
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• 2000

This study proposed to beam-column joint model consisting of different type structural member to develop new structural system in the structural viewpoint as to a method to overcome various problem according to change of construction environment. This study promoted rigidity and capacity to stiffen reinforced concrete for steel structure end to increase rigidity of long spaned steel beam, and welt to steel flange to anchor U-shaped main bar of SRC structure end to easy stress flow between the different type structure. Through the series of experiments, proposed to possibility of this joint model, and investigated joint rigidity and capacity.