• Journal of the Society of Cosmetic Scientists of Korea
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• v.34 no.4
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• pp.287-301
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• 2008

In order to develop a new depigmenting agent, extracts were obtained from 60 native plants and their antimelanogenic activities were screened by evaluating the inhibitory effect on tyrosinase which is a major enzyme responsibles for the melanin synthesis. The extracts of Trichosanthes kirilowii fruits, Phyllostachys bambusoides inner films (BIF), Clerodendrum trichotomum leaves, and Acer okamotoanum leaves showed relatively high inhibitory effect on tyrosinase and their $IC_{50}$ values were $50{\sim}100{\mu}g/mL$. The extract of BIF inhibited melanin synthesis of B16F10 melanoma cells by 52%, which was the highest among those of various extracts. Furthermore, the effect of BIF extract is 10% higher than that of arbutin (42%), a popular depigmenting agent in Korea. Ten compounds having antimelanogenic activity were isolated from the BIF extract by solvent extraction and chromatography. These compounds were identified as phenolic derivatives: SM701, SM702, SM703, and BPR211 were hydroquinone derivatives; SM707 a gallic acid derivative; SM704, SM705, SM706, SM708 and SM709 ferulic acid derivatives. The free radical scavenging activities of these compounds were measured and compared to those of hydroquinone and vitamin C. The $SC_{50}$ values scavenging 50% DPPH of SM702 and SM709 were $60{\sim}70{\mu}M$ similar to that of hydroquinone and those of SM701 and SM708 were $30{\sim}40{\mu}M$ slightly lower than that of vitamin C. These results suggest the presence of components having high antioxidant activity in the BIF extract. The SM709, identified as 1,2-O-diferulylglycerol, inhibited the activities of tyrosine hydroxylase and dopa oxidase by 18 and 60%, respectively. The SM709 also inhibited the melanin synthesis of B16F10 melanoma cells by 62% and this was the highest antimelanogenic activity among those obtained from the various purified compounds. Therefore, antimelanogenic activity of the BIF extract was concluded to be due to both inhibition of DOPA oxidase and antioxidant activity.

• Journal of Society of Preventive Korean Medicine
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• v.19 no.2
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• pp.135-144
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• 2015

Objective : Saengmaek-san (SM) has been commonly used in Korea to treat various diseases that involve the respiratory and cardiovascular system. However, to date, the mechanism underlying the effects of osteoclasts differentiation of SM has not been clearly understood. Method : To evaluate the effect of SM on osteoclast differentiation, we induced RAW 264.7 cells to be differentiated to osteoclasts by RANKL, and we performed RT-PCR to measure gene expression. Results : SM decreased the number of TRAP(+) MNCs in RANKL-induced osteoclast. SM decreased the expression of MMP-9, cathepsin K1, TRAP, NFATc1, MITF, and COX-2 in the osteoclast. But SM increased the expression of iNOS, $TNF-{\alpha}$ and IL-6 in osteoclast. Conclusion : It is concluded that SM might decrease the bone resorption resulted from decrease of osteoclast differentiation and it's related gene expression.

• Journal of the Korean Magnetics Society
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• v.3 no.3
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• pp.196-200
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• 1993

$(Sm_{0.5}RE_{0.5})Fe_{11}Ti$ compounds have tetragonal $ThMn_{12}$-type structure and show the uniaxial magnetocrystalline anisotropy with the easy magnetization c-axis. Among the $(Sm_{0.5}RE_{0.5})Fe_{11}Ti$ series, RE=Sm shows the highest anisotropy field of 11200 kA/m(140 kOe). On the other hand, RE=Nd has the highest saturation magnetization of $122.3\;Am^{2}/kg$(122.3 emu/g) and RE=Gd the highest Curie temperature of $326^{\circ}C$.

• Journal of Biosystems Engineering
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• v.37 no.1
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• pp.58-64
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• 2012

Purpose: The objective of this study was to investigate the feasibility of anaerobic digestion of Chinese cabbage waste juice (CCWJ) and swine manure(SM). Methods: The anaerobic digestion test was conducted under batch and continuous conditions at mesophilic temperature ($36-38^{\circ}C$). The batch test was divided into Experiment I and II. In the Experiment I, biogas potential and production rate of CCWJ was evaluated. In Experiment II the effect of F/M ratio (2.0, 3.2, 4.9) at mixture ratio of 25:75(CCWJ: SM, % vol. basis) on biogas yield was studied. Results: CCWJ produced biogas and methane yield of 929 and 700 mL/g VS added respectively. The biogas yield from the mixture of CCWJ and SM was almost same at F/M ratio of 2.0 and 3.2 but dropped by 14% when F/M ratio increased from 3.2 to 4.9. In continuous test the mixture of CCWJ and SM (25:75, % vol. basis) produced biogas yield of 352 mL/g VS added which is around 11% higher compared to biogas yield from SM alone. Addition to biogas yield digester performance was also improved with co-digestion of CCWJ with SM. Conclusions: The results showed that the anaerobic digestion of CCWJ with SM could be promising for improving both the biogas yield and digester performance at mesophilic temperature.

• Polymer(Korea)
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• v.39 no.2
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• pp.191-199
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• 2015

In order to improve the low impact resistance of polystyrene without harming its transparency the styrene monomer was copolymerized with transparent butyl acrylate (BA), and methylmethacrylate (MMA) to obtained a poly(styrene-co-butylacrylate) P(SM-co-BA) and a terpolymer copolymer P(SM-co-BA-co-MMA). The polymers were then cross-linked with the aid of a cross-linking agent dicumylperoxide (DCP), and their mechanical and optical properties were tested. It was found that the contents of monomers and DCP affect the mechanical, thermal, and optical properties of the polymers. An increase in BA contents in P(SM-co-BA) and P(SM-BA-MMA) improved the mechanical strength, but the optical properties remained the same with some exception for P(SM-co-BA). An increase in the DCP contents improved the mechanical but found losses in the optical properties.

• Journal of the Korean Applied Science and Technology
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• v.34 no.3
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• pp.650-656
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• 2017

The water-swollen hydrogels containing silicone or fluorine were prepared by copolymerization of 2-hydroxy ethyl methacylate (HEMA) with 3-(trimethoxysilyl)propyl methacrylate(SM) or 2,2,2-trifluoroethyl acrylate(FA). When the content of SM or FA increased in copolymers, there was tendency of water absorbance to decrease, whereas contact angles to increase. The hydrogels containing FA showed 2 ~ 4% higher water content and 4 ~ 5% lower contact angles compared to that of SM. Tensile strengths decreased as the content of SM increased. However, FA exhibited strength of $2.2Mpa/cm^2$ which is similar to $2.3Mpa/cm^2$ of B. FA, which implies comparatively low adherence, hence, showed better protein resistance properties than SM-based hydrogel. The photo-polymerization was also applied instead of thermal polymerization to enhance the energy efficiency. As a result, the reaction yield reached over 95% within 1 minute.

• Journal of the Korean Magnetics Society
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• v.4 no.3
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• pp.226-232
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• 1994

Rapidly solidified $SmFe_{7+x}M_{x}(M=Mo,\;V,\;Ti)$ compound were found to crystallize in the ${Sm(Fe,\;M)}_{7}$ based stable magnetic phase by introducing a second transition element into the Sm-Fe binary system. The ${Sm(Fe,\;M)}_{7}$ phase exhibits the highest Curie temperatuer ($T_{c}=355^{\circ}C$) ever Known in the Sm-Fe magnetic systems with a quite high intrinsic coercivity($_{i}H_{c}=3~6\;kOe $). The ${Sm(Fe,\;M)}_{7}$ phase remains stable even after annealing if once form during the rapid solidification. The primary reason for the high coercive force is due to the fine grain size($2000~8000\;{\AA}$)of the magnetic ${Sm(Fe,\;M)}_{7}$ matrix phase, and the enhanced Curie temperature is attributed to the extended solid-solubility of the additive transition elements in Fe matrix, which leads to volume expansion of the ${Sm(Fe,\;M)}_{7}$ cell causing an enhanced coupling constant of Fe atoms.

• Journal of the Korean Ceramic Society
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• v.35 no.4
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• pp.355-363
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• 1998

The oxygen flux of SDC ($Sm_2O_3\;doped\;CeO_2$) solid electrolyte membranes with electronic and oxygen ion-ic conductivities has been investigated as a basic research in order to develop the conversion process of na-tural gas to syngas using the ceramic membrane reactor. Tube type membranes(1 mm thickness) were fa-bricated by slip casting of SDC powders prepared by the oxalate coprecipitaion method. Dense oxygen per-meation membranes(0.1 mm thickness) could be synthesized via sintering at $1450^{\circ}C$ for 2h and their re-lative density was over 95% The oxygen flux through SDC membranes doped 20mol% $Sm_15$ was about $1.13{\times}10^{-5}\;mol/m_2{\cdot}sec$ at low temperature around $800^{\circ}C$. In addition the SDC membranes showed a good thermaal stability for a long period of service.

• Journal of the Korean Magnetics Society
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• v.13 no.5
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• pp.198-203
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• 2003

To investigate whether the use of hard magnetic film is available to generate bias magnetic field for a magnetoimpedance sensor, the magnetic properties of SmCo hard magnetic films were investigated as a function of their compositions. The saturation magnetization decreased with Sm content increasing in SmCo films. And, the coercive force increased in the extent of Sm content of 28 at%, but decreased as Sm content increased moreover. The bias field effect of SmCo film to amorphous CoZrNb film was investigated with the magnetization corves, permeabilities, and magnetic domain structures of SmCo/CoZrNb multilayers. The bias field of about 60 Oe was observed in the film with 3 mm ${\times}$ 0.5 mm, which can be constructed as a MI sensor, and this result strongly indicates that the bias field generated from a hard magnetic film is adequate to enhance the sensitivity of a MI sensor with hard/soft magnetic multilayer structure.

• Korean Journal of Medicinal Crop Science
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• v.13 no.3
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• pp.118-121
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• 2005

Karyotypes were established in seven Angelica species cultivated in Korea. The somatic chromosome numbers were 2n = 2x = 22 with the basic number of x = 11 in all Angelica plants examined. Their metaphase chromosomes ranged from 3.56 ${\mu}M$. to 8.91 x. in length. Distinctive Karyotypes were found in two species, A. tenuissima with all metacentries, K(2n) = 2x = 22m, and A. genuflexa with all subtelocentrics, K(2n) = 2x = 22st. Karyotype formulas of A. gigas, A. acutiloha, A. sinensis, A. decursiva and A. dahurica were K(2n) = 2x = 20m + 2sm, K(2n) = 2x = 12m + 10sm, K(2n) = 2x = 16m + 6sm, K(2n) = 2x = 18m + 4sm and K(2n) = 2x = 10m + 10sm + 2st, respectively. Cytological data showed that chromosomal polymorphisms within species were observed in Angelica plants compare to other regions.