• Journal of Radiation Protection and Research
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• v.27 no.2
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• pp.101-110
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• 2002

The concentrations and activity ratios of $^{137}Cs,\;^{90}Sr\;^{238}Pu$ and $^{239-240}Pu$ in sediment($0sim}20\;$cm) at 15 coastal stations of Korea were determined. The mean concentrations of $^{137}Cs,\;^{90}Sr\;^{238}Pu$ and $^{239-240}Pu$ are $2.24{\pm0.79\;Bq{\cdot}kg^{-1}-dry,\;0.20{\pm}0.04 Bq{\cdot}kg^{-1}-dry,\;0.009{\pm}0.005\;Bq{\cdot}kg^{-1}-dry}$ and $0.27{\pm}0.17\;Bq{\cdot}kg^{-1}-dry$, respectively. The mean activity ratios of $^{137}Cs,\;^{90}Sr$, $^{239-240}Pu/^{137}Cs$ and $^{238}Pu/^{229-240}Pu$ and atomic ratio of $^{240}Pu/^{239}Pu$ are $11.2{\pm}2.9,\;0.123{\pm}0.053$ and $0.033{\pm}0.017$ and $0.218{\pm}0.036$, respectively. The concentrations and activity ratios in sediment samples are similar to those reported from neighbouring country in the northern hemisphere. The correlation coefficient of $^{137}Cs$ and $^{239-240}Pu$ is 0.80. The correlation coefficient of $^{137}Cs$ and soil organic matter(SOM), and $^{239-240}Pu$ and clay content are 0.69 and 0.67, respectively.

• Journal of Radiation Protection and Research
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• v.21 no.2
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• pp.91-98
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• 1996

An optimized method for determining beta-emitting $^{241}Pu$ in the presence of alpha-emitting nuclides was developed using a liquid scintillation counting system. Pulse shape analysis (PSA) level was set using pulse-shape discrimination method and the $^{241}Pu$ counting channel was adjusted for maximum value of figure of merit using the 241pu standard source. The volume of scintillant was determined for the maximum value of counting efficiency. This optimized method has been applied to environmental samples to measure concentration of $^{241}Pu$ in soils and mosses. Also it has been identified the origin of Pu deposited in Korea from the activity ratio of $^{241}Pu/^{239,\;240}Pu$.

• Textile Coloration and Finishing
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• v.15 no.3
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• pp.168-175
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• 2003

Ultramicrofiber(UMF) PET knitted fabric and regular PET plain woven fabric as reference sample were impregnated with waterborne polyurethane(PU) in a two-step process with dyeing/PU treatment and PU treatment/dyeing to investigate the effect of the treatment sequence. The waterborne PU impregnated fabrics were dyed with two kinds of vat and disperse dyes to investigate the dyeing properties and the dyeing fastnesses. In vat dyeing the rank of color strength(K/S) was in order of dyeing/PU impregnation > dyeing only > PU impregnation/dyeing, whereas in case of disperse dyeing, the order was dyeing/PU impregnation > PU impregnation/dyeing >dyeing only. Wash fastness of vat dyeing showed a higher 2-3 grade than disperse dyeing, while rubbing and light fastnesses were not good for disperse dyes.

• Journal of the Korean Chemical Society
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• v.43 no.3
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• pp.280-285
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• 1999

Separation of plutonium species was studied by ion chromatography installed in a glove box for the determination of plutonium element. The plutonium species, $PuO_2^{2+},\; PC^{4+}\; and\; Pu^{3+}$, were stably separated on dynamically equilibrated cation exchanger using 1-octanesulfonate and ${\alpha}$-HiBA eluant after controlling the plutonium oxidation states with KI, $NaNO_2\;or=;KBrO_3$ based on the oxidation-reduction potentials. For the separation of plutonium from other matrix, $PuO_2^{2+}\; and\; Pu^{4+}$ were reduced to $Pu^{3+}$ with KI and $NaNO_2$ followed by cation exchange chromatography.

• Textile Coloration and Finishing
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• v.15 no.5
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• pp.285-293
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• 2003

Waterborne PU membrane was prepared from waterborne PU dispersion solution to investigate physical and staining properties. The staining properties of waterborne PU membrane with acid dyes and disperse dyes were observed. The physical properties of the PU membrane were investigated by X-ray diffraction and IR spectroscopy. The staining property of waterborne PU membrane for azo acid dyes is better than that of disperse dyes. X-ray diffraction peaks sharpened and tensile strain and stress increased with heat setting temperature.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.3
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• pp.306-313
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• 2017

Purple bamboo salt (PuBS) is commonly used as a medicinal food in Korea and has beneficial potentials such as antioxidant and anti-inflammatory effects. Rubus coreanus is called Bokbunja, which is used as a traditional medicine for treating asthma, impotence, and allergic diseases in Korea. The aim of present study was to investigate the immunostimulatory effect of PuBS composed with Rubus coreanus (PuBS-R). We performed comparative analysis between PuBS and PuBS-R in Raw264.7 cells, which is a mouse macrophage cell line, and peritoneal macrophages isolated primarily from the mouse peritoneal cavity. We evaluated cytotoxicity and the immune cytokine response in PuBS- and PuBS-R-treated cells. Both PuBS and PuBS-R did not have any cytotoxicity in Raw264.7 cells up to $500{\mu}g/mL$. Gene and protein levels of immune cytokines such as tumor necrosis $factor-{\alpha}$ ($TNF-{\alpha}$), $interferon-{\gamma}$ ($IFN-{\gamma}$), interleukin (IL)-10, and IL-12 were significantly elevated by PuBS-R more than PuBS in Raw264.7 cells. Moreover, we evaluated the immunostimulatory effects of PuBS-R on mouse primary peritoneal macrophages. Protein levels of inducible nitric oxide synthase, $TNF-{\alpha}$, $IFN-{\gamma}$, IL-10, and IL-12 were significantly higher in PuBS-R-treated peritoneal macrophages than PuBS-treated peritoneal macrophages. These results suggest the potential immunostimulatory effect of PuBS-R for immunity against harmful infection.

• Applied Chemistry for Engineering
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• v.21 no.5
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• pp.500-504
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• 2010

The PU-g-MWNTs/PU film was synthesized by simple blending method to fabricate composites which have excellent mechanical and electrical properties. PU-g-MWNTs based composite revealed much enhanced dispersity than pristine MWNTs composite because of interfacial interaction related with interfacial compatibility between polymer matrix and PU on the MWNTs surface. The electro-conductivity of composite was measured as a function of PU-g-MWNTs concentration. The results were correlated with percolation threshold theory. As a result, the critical concentration and exponent of electro-conductivity behavior was equal to 0.78 wt% and 0.945.

• Applied Chemistry for Engineering
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• v.10 no.5
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• pp.639-643
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• 1999

Interpenetrating polymer networks(IPNs) composed of castor oil(CO) polyurethane(PU) and epoxy resin were prepared by the simultaneous polymerization technique. Two types of PU were prepared using 1,4-butanediol(BD) and BD/trimethylolpropane(TMP) as a chain extending agent and crosslinking agent. The PU/epoxy based on BD as a chain extending agent showed more shift in the damping peak than PU/epoxy based on BD/TMP as the PU content was increased. BDPU/epoxy simultaneous interpenetrating polymer networks(SINs) had a better compatibility than BD/TMP-PU/epoxy SINs. For both systems, it was postulated that unique network formation of PU/epoxy SINs as a chain extending agent and crosslinking agent had occurred to a significant extent of phase mixing. The types of chain extender in the PU were found to be an important factor in determining the phase mixing of the IPNs. When the BD/TMP-PU reaction was faster than epoxy network, the extent of phase mixing was retarded by decreasing entanglement of networks. It was found that both PU/epoxy SINs provided enhanced flexural properties and fracture toughness, fracture surfaces of BDPU/epoxy and BD/TMP-PU/epoxy SINs showed the localized shear deformation and generation of stress whitening associated with the cavitation.

• Analytical Science and Technology
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• v.14 no.1
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• pp.28-33
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• 2001

The ion chromatography for the separation of plutonium species which are suggested to be $Pu^{3+}$, $Pu^{4+}$, $PuO_2{^+}$ and $PuO_2{^{2+}}$ in natural water was studied. Two separation methods were performed; 1) two-column method containing each of $SiO^-$ and SiO-$SO_3{^-}$ cation exchanger, 2) IC with AG11 column and the eluent of oxalate/nitric acid. Separation conditions for $Eu^{3+}$, $Th^{4+}$, $NpO_2{^+}$, $UO_2{^{2+}}$ in place of plutonium species were acquired from preliminary tests. When these conditions were applied to separate the plutonium species, two-column method was separated them successfully. However, the IC method with oxalate eluent was difficult in the separation of plutonium species due to the change of $Pu^{3+}$ and $PuO_2{^{2+}}$ to $Pu^{4+}$ and $PuO_2{^+}$ respectively.

• Textile Coloration and Finishing
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• v.20 no.5
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• pp.35-40
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• 2008

Dyeing and washing fastness properties of polyurethane-impregnated polyester (PU-impregnated PET), and the distribution of two disperse dyes between PET and PU film were studied to investigate the effect of PU portion to exhaustion and washing fastness. Dyeing properties of PU-impregnated PET were quite different with those of PET: PU-impregnated PET absorbed disperse dye linearly from the early stage of dyeing to equilibrium, and it exhibited excellent build-up property up to 4 %owf dyeing. The absorbed dye on PU film at early dyeing stage migrated to more substantive PET at the temperature higher than $115^{\circ}C$. The amount of exhausted dye on PET portion was larger than on PU film and the distribution ratio was $2.08{\sim}2.34$. The grade of washing fastness of PU-impregnated PET was the same as or lower by $0.5{\sim}1$ grade than PU film whose washing fastness was lower by $0.5{\sim}1$ than PET.