• Progress in Superconductivity and Cryogenics
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• v.19 no.2
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• pp.19-24
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• 2017

Cryogenic milling which is a combined process of low-temperature treatment and mechanical milling was applied to fabricate high critical current density $(J_c)MgB_2$ bulk superconductors. Liquid nitrogen was used as a coolant, and no solvent or lubricant was used. Spherical Mg ($6-12{\mu}m$, 99.9 % purity) and plate-like B powder (${\sim}1{\mu}m$, 97 % purity) were milled simultaneously for various time periods (0, 2, 4, 6 h) at a rotating speed of 500 rpm using $ZrO_2$ balls. The (Mg+2B) powders milled were pressed into pellets and heat-treated at $700^{\circ}C$ for 1 h in flowing argon. The use of cryomilled powders as raw materials promoted the formation reaction of superconducting $MgB_2$, reduced the grain size of $MgB_2$, and suppressed the formation of impurity MgO. The superconducting critical temperature ($T_c$) of $MgB_2$ was not influenced as the milling time (t) increased up to 6 h. Meanwhile, the critical current density ($J_c$) of $MgB_2$ increased significantly when t increased to 4 h. When t increased further to 6 h, however, $J_c$ decreased. The $J_c$ enhancement of $MgB_2$ by cryogenic milling is attributed to the formation of the fine grain $MgB_2$ and a suppression of the MgO formation.

• Korean Journal of Crystallography
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• v.15 no.2
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• pp.93-98
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• 2004

The structure of C_{28}H_{41}N_4O_4Br\;{\cdot}\;2H_2O$ has been determined by X-ray deffraction methods. The crystal system is triclinic, space group Pl, unit cell constants, a=9.000(1) $\AA$, b=9.312(3) $\AA$, c=9.344(2) $\AA$, $\alpha=89.37(20)^{\circ},\;\beta=68.81(3)^{\circ},\;\gamma=84.70(4)^{\circ},\;V=726.7(8){\AA},\;T=298K,\;Z=1,\;D_c=1.402Mgm^{-3}$. The intensity data were collected on an Enraf-Nonius CAD4 Diffractometer with graphite monochromated $MoK\alpha$ radiation $(\lambda=0.71073\;{\AA}$. The molecular structure was solved by direct methods and refined by full-matrix least squares to a final $R=5.95\%$ for 2521 unique observed $F_0>4\sigma(F_0)$reflections and 370 parameters.

• Journal of the Korean Chemical Society
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• v.20 no.1
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• pp.19-34
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• 1976

The crystal structure of sodium sulfisoxazole hexahydrate, $C_{11}H_{12}N_3O_3SNa{\cdot}6H_2O$,has been determined by X-ray diffraction method. The compound crystallizes in the monoclinic space group $$P2_1}c$$ with a = 15.68(3), b = 7.70(2), c = 17.94(4)${\AA}$, ${\beta}$ = $118(2)^{\circ}$ and Z = 4. A total of 1717 observed reflections were collected by the Weissenberg method with $CuK{\alpha}$ radiation. Structure was solved by heavy atom method and refined by block-diagonal least-squares methods to the R value of 0.14. The conformational angle formed by the S-C(l) bond with that of N(2)-C(7), when the projection in taken along the S-N(2), is $73^{\circ}.$ The benzene ring is planar and makes an angle of $60^{\circ}$ with the plane of the isoxazole ring, which is also planar. The sodium atom has a distorted octahedral coordination of N(l) and five oxygen atoms from hydrate molecules. Sodium sulfisoxazole hexahydrate shows fourteen different hydrogen bondings in the crystal. These are six $O-H{\cdots}O-H bonds, three $O-H{\cdots}O$ bonds, two $O-N{\cdots}N,$ one $N-H{\cdots}O,O-H{\cdots}N,N-H{\cdots}O-H$ bond, with the distances in the range of 2.71 to $3.04{\AA}.$.

• Bulletin of the Korean Chemical Society
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• v.23 no.1
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• pp.35-40
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• 2002

Photoreaction of guest organic anions in layered organic-inorganic hybrid materials was investigated. The layered hybrids were synthesized by an anion-exchange reaction of $[LiAl_2(OH)_6]Cl{\cdot}yH_2O$ layered double hydroxide with aqueous (Z,Z)- and (E,E)-muconates under inert atmospheric condition, to give new organicinorganic hybrids of $[LiAl_2(OH)_6]_2[(Z,Z)-C_6H_4O_4]{\cdot}zH_2O$ and $[LiAl_2(OH)_6]_2[(E,E)-C_6H_4O_4]{\cdot}H_2O$, respectively. The basal spacings calculated by XRPD of intercalates indicate that muconate anions have almost vertical arrangements against the host $[LiAl_2(OH)_6]^+$ lattices in the interlayer of organic-inorganic hybrid materials. When UV light was irradiated on the suspension of $[LiAl_2(OH)_6]_2[(Z,Z)-C_6H_4O_4]{\cdot}zH_2O$, the (Z,Z)-muconate anions of the gallery space of hybrids were polymerized in the aqueous media while it was isomerized into more stable (E,E)-muconate in the methanollic suspension in the presence of catalytic amount of molecular iodine. All the products were characterized using elemental analysis, TGA, XRPD, FT-IR, $^1H$ NMR and $^{13}C$ CP-MAS NMR.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.202.2-203
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• 2003

전통주의 계승발전을 위해 전통주의 개선과 재현의 필요성이 높아짐에 따라 지난날 맛 좋았던 우리의 전통주의 연구와 개발이 활발히 진행되고 있다. 또한 최근 미곡의 과잉생산으로 인한 과잉쌀 생산에 대한 수요체 창출을 위한 쌀가공품의 개발이 매우 시급한 실정이다. 최근 알콜농도가 낮은 술을 선호하는 경향과 전통주의 특수한 풍미로 인하여 현재 전통주는 많은 사람들로부터 각광을 받고 있어서 현재 몇몇 지역에서 민속주와 토속주가 허가되어 시판되고 있다. 진양주는 전남 해남지역의 전통민속주로서 해남지역에서 생산되는 찹쌀을 원료로 하여 상온에서 발효시키는 독특한 방법으로 제조되는데 이 진양주는 발효과정에서 외부환경의 영향을 많이 받게 된다. 그중 외부온도는 진양주의 품질에 직접적인 영향을 미치게 되는데 아직까지는 진양주제조과정에서 최적발효온도에 대한 연구는 보고된 것이 없다. 본 연구에서는 발효온도를 2$0^{\circ}C$와 $25^{\circ}C$로 하였을 때 발효과정에서 술의 품온, pH, 당도, 알콜함량, 총산의 변화를 조사하였으며 관능검사를 통하여 종합적인 기호도를 평가하여 최적의 발효온도를 탐색하고자 했다. 발효과정에서 술의 품온은 온도계를 사용하여 측정하였고 pH는 pH-meter로 측정하였으며 당도는 당도계를 이용하여 측정하였다. 알콜함량과 총산은 국세청의 주류분석규정에 따라 증류법과 중화적정법을 사용하여 측정하였다. 관능검사는 식품공학과 대학원생과 학부생 10명을 대상으로 종합적인 기호도에 대하여 5단계 평점법으로 실시하였다. 2$0^{\circ}C$에서 발효시 품온은 20.2~23.8$^{\circ}C$사이에서, $25^{\circ}C$에서 발효시 품온은 25.2$^{\circ}C$~28.2$^{\circ}C$사이에서 변화되었고 pH는 2$0^{\circ}C$ 발효시 3.47~4.62 사이에서, $25^{\circ}C$ 발효시 pH는 3.28~4.65사이에서 변화되었고 최종 pH는 2$0^{\circ}C$에서 발효시 3.71로써 $25^{\circ}C$ 발효시 3.58보다 높았다. 최종당도는 2$0^{\circ}C$, $25^{\circ}C$ 발효시 각각 10.2。Brix와 8.4。Brix 였고 알콜농도는 2$0^{\circ}C$발효시 13.8%로 $25^{\circ}C$ 발효시 14.8% 낮았으며 총산은 2$0^{\circ}C$ 발효시 1.32%로 $25^{\circ}C$ 발효시 1.62%보다 낮게 나타났다. 관능검사를 통한 종합적인 기호도는 2$0^{\circ}C$에서 발효시킨 진양주가 4.2로써 $25^{\circ}C$에 발효시킨 진양주 3.5보다 높은 것으로 나타났다. 관능검사시 $25^{\circ}C$에서 발효한 진양주는 신맛이 많이 난다는 결과로 볼 때 최종 pH가 3.58로 낮고 총산이 1.62%로 높아서 나온 결과라고 생각된다. 결론적으로 진양주를 제조할 시 발효온도는 2$0^{\circ}C$가 발효온도 $25^{\circ}C$보다 더 적합하다고 생각된다.

• Bulletin of the Korean Chemical Society
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• v.18 no.8
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• pp.791-793
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• 1997

• Korean Journal of Pharmacognosy
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• v.16 no.4
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• pp.233-238
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• 1985

A number of sedative alkaloids were isolated from Sanjoin(酸棗仁), the seeds of Zizyphus vulgaris Lamark var. spinosus Bunge (Rhamnaceae) which is an important Chinese medicinal material used to treat insomnia and sometimes to treat sleepiness. Those compounds were designated as Sanjoinine-A, B, C, D, etc. depending on the order of increasing polarity. Sanjoinine-A, $C_{31}H_{42}N_4O_4$, $mp\;249^{\circ}$, $[{\alpha}]^{27}_D-316$, Sanjoinine-B, $C_{30}H_{40}N_4O_4$, $mp\;212{\sim}4^{\circ}$, Sanjoinene, $C_{29}H_{35}N_3O_4$, $mp\;281{\sim}2^{\circ}$, $[{\alpha}]^{22}_D-272$, Sanjoinine-D, $C_{32}H_{46}N_4O_5$, $mp\;256{\sim}8^{\circ}$, $[{\alpha}]^{22}_D-53.6$, Sanjoinine-F, $C_{31}H_{42}N_4O_5$, $mp\;228{\sim}9^{\circ}$, $[{\alpha}]^{22}_D-215$, and $Sanjoinine-G_1,\;C_{31}H_{44}N_4O_5,\;mp\;236{\sim}8^{\circ},\;[{\alpha}]^{22}_D-68.6$, were found as 14-membered cyclic peptide alkaloids, $Sanjoinine-G_2,\;C_{30}H_{42}N_4O_4,\;mp\;182^{\circ},\;[{\alpha}]^{22}_D-79.2$, as being open chain peptide alkaloid, and Sanjoinine-E, $C_{19}H_{21}NO_2$, $mp\;166^{\circ}$, $[{\alpha}]^{20}_D-146.2$, N-Methylasimilobine, $C_{18}H_{19}NO_2$, $mp\;193{\sim}5^{\circ}$, $[{\alpha}]^{20}_D-204$, Sanjoinine-Ia, $C_{18}H_{19}NO_2$, $mp\;155{\sim}7^{\circ}$, $[{\alpha}]^{20}_D-140$, Sanjoinine-Ib, $C_{19}H_{21}NO_4$, $mp\;184^{\circ}$, Sanjoinine-K, $C_{16}H_{19}NO_3$, $mp\;159{\sim}61^{\circ}$, $[{\alpha}]^{20}_D+35$, Caaverine, $C_{17}H_{17}NO_2$, $mp\;204^{\circ}$, $[{\alpha}]^{20}_D-80$, and Zizyphusine, $C_{20}H_{24}NO_4$, $mp\;214{\sim}6^{\circ}$, $[{\alpha}]^{20}_D+317$ as being aporphine alkaloids. The heat treatment of the cyclic peptide alkaloids produced their isomeric products which showed enhanced sedative activity. The chemical structure of the isomeric products will be discussed.

• YAKHAK HOEJI
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• v.57 no.5
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• pp.309-315
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• 2013

Cyanidin-3-glucoside (C3G), an anthocyanin, is one of the most widespread dietary flavonoids. We investigated the effects of C3G in PMA/ionomycin (PI)-induced RBL-2H3 cells. C3G inhibited the production of IL-4 and IL-13 and also decreased the level of mRNA in a dose-dependent manner. Furthermore, western blot analysis implied that C3G down-regulated the protein level of c-Jun, NF-ATc1 and NF-${\kappa}B$ but not c-Fos. Taken together, we suggest that C3G may have suppressive effects on Th2 cytokines and will be studied further to develop as functional foods that help alleviate allergy symptoms.

• Journal of Korean Society for Atmospheric Environment
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• v.12 no.2
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• pp.121-130
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• 1996

The catalysts composed of Pt, Pd and W as active-components, $Al_{2}O_{3}$ and $SiO_{2}$ as supports, were perpared on the honeycomb type substrate and characterized by BET, SEM, TGA, FT-IR and XRD for diesel emission control. CO, $C_{3}H_{6}$, and $SO_{2}$ oxidation was carried out over these catalysts in a fixed bed continuous flow reactor at the temperatures between 100-500.deg.C and reactant gas was composed of 10 vol.% $O_{2}$, 1 vol.% CO, 0.8 vol.% $C_{3}H_{6}$ and 88.2 vol.% $N_{2}$. It was found that under these experimental conditions, the CO, $C_{3}H_{6}$ oxidation activity of Pt-W catalyst was higher than that of any other prepared catalyst, and this catalyst had also a good inhibition effect on $SO_{2}$ oxidation. Also it was show that the influence of $SO_{2}$ on $Al_{2}O_{3}$ was more sever than that of $SO_{2}$ on $SiO_{2}$.

• Journal of Pharmacopuncture
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• v.19 no.1
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• pp.59-69
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• 2016

Objectives: The mushroom Ganoderma lucidum has been widely used as a traditional herbal medicine for many years. Although several studies have focused on the anti-oxidative activity of this mushroom, the molecular mechanisms underlying its activity have not yet been clearly established. The present study investigated the cytoprotective effect of ethanol extract of Ganoderma lucidum (EGL) against oxidative stress (hydrogen peroxide, $H_2O_2$) and elucidated the underlying mechanisms in a C2C12 myoblast cell line. Methods: Oxidative stress markers were determined by using the comet assay to measure reactive oxygen species (ROS) generation and deoxyribonucleic acid (DNA) damage. Cell viability and Western blotting analyses were employed to evaluate the cellular response to EGL and $H_2O_2$ in C2C12 cells. Transfection with nuclear factor erythroid 2-related factor 2 (Nrf2)-specific small interfering ribonucleic acid (siRNA) was conducted to understand the relationship between Nrf2 expression and $H_2O_2$-induced growth inhibition. Results: The results showed that EGL effectively inhibited $H_2O_2$-induced growth and the generation of ROS. EGL markedly suppressed $H_2O_2$-induced comet-like DNA formation and phosphorylation of histone H2AX at serine 139 ($p-{\gamma}H2AX$), a widely used marker of DNA damage, suggesting that EGL prevented $H_2O_2$-induced DNA damage. Furthermore, the EGL treatment effectively induced the expression of Nrf2, as well as heme oxygenase-1 (HO-1), with parallel phosphorylation and nuclear translocation of Nrf2 in the C2C12 myoblasts. However, zinc protoporphyrin IX, a HO-1 inhibitor, significantly abolished the protective effects of EGL against $H_2O_2$-induced accumulation of ROS and reduced cell growth. Notably, transient transfection with Nrf2-specific siRNA attenuated the cytoprotective effects and HO-1 induction by EGL, indicating that EGL induced the expression of HO-1 in an Nrf2-dependent manner. Conclusion: Collectively, these results demonstrate that EGL augments the cellular anti-oxidant defense capacity through activation of Nrf2/HO-1, thereby protecting C2C12 myoblasts from $H_2O_2$-induced oxidative cytotoxicity.