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Toxicity Reduction and Improvement of Anticancer Activities from Rhodiola sachalinensis A. Bor by Ultra High Pressure Extracts Process (초고압 공정에 의한 홍경천의 독성 감소 및 항암활성 증진)

  • Kim, Cheol-Hee;Kwon, Min-Chul;Qadir, Syed Abdul;Hwang, Baik;Nam, Jong-Hyeon;Lee, Hyeon-Yong
    • Korean Journal of Medicinal Crop Science
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    • v.15 no.6
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    • pp.411-416
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    • 2007
  • This study was performed to investigate the reduction of toxicity and improvement of anticancer activities from R. sachalinensis by ultra high pressure extracts process. The cytotoxicity on human kidney cell (HEK293) and human lung cell (HEL299) was showed below 20.4% and 21.6% as compare to normal extracts in adding 1.0 $mg/m{\ell}$ concentration. This showed that toxic materials through ultra high pressure processing is broken or degraded. Because bond such as hydrogen bond, electrostatic bond, Van der waals bond, the hydrophobic bond, can be broken by high pressure. The anticancer activity was also increased in over 7% by high pressure processing in A549, AGS, MCF-7 and Hep3B cells. The result showed that extraction by high pressure have low cytotoxicity and high anticancer activity. So, the high pressure extraction technology can play an important role in eruption of new material with high biological activity.

Effect of Branching-agent Content on the Electrochemical Properties of Partially Fluorinated Poly(Arylene Ether Sulfone) Block Ionomer Membranes (부분불소계 Poly(Arylene Ether Sulfone) 블록이오노머막의 전기화학적 특성에 대한 분지체 함량의 효과)

  • Jeon, Seong-Hoon;Chang, Bong-Jun;Kang, Ho-Cheol;Kim, Jeong-Hoon;Joo, Hyeok-Jong
    • Membrane Journal
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    • v.21 no.1
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    • pp.1-12
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    • 2011
  • Partially fluorinated poly(arylene ether sulfone) block ionomer membranes with different branch degree for fuel cell applications were investigated. A sulfonable monomer, a non-sulfonable monomer and a trifunctional branching agent were synthesized and the sulfonable monomer was oligomerized to obtain block structures. The oligomer was then further polymerized with the non-sulfonable monomer and the branching agent. The mole ratio of oligomer : non-sulfonable monomer was fixed at 4:6 and the content of the branching agent was varied from 0 to 2 mol% (BBC-40Bx). Post-sulfonation of BBC-40Bx was carried out using chlorosulfonic acid (CSA) (SBBC-40Bx). All the synthesized compounds were characterized by $^1H$-NMR, $^{19}F$-NMR and FT-IR. It was confirmed that the ion exchange capacity (IEC), water uptake and ion conductivity of SBBC-40Bx increased with the increment of branching agent content.

Properties of ZnS:Cu,Cl Thick Film Electroluminescent Devices by Screen Printing Method (스크린인쇄법에 의한 ZnS:Cu,Cl 후막 전계발광소자의 특성)

  • No, Jun-Seo;Yu, Su-Ho;Jang, Ho-Jeong
    • Korean Journal of Materials Research
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    • v.11 no.6
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    • pp.448-452
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    • 2001
  • The ZnS:Cu,Cl thick film electroluminescent devices with the stacking type(separated with phosphors and insulator layers) and the composite type (mixed with phosphor and insulator materials) emission layers were fabricated on ITO/glass substrates by the screen printing methods. The opical and electrical properties were investigated as fundations of applied voltages and frequencies. In the stacking type, the luminance was about 58 cd/$\m^2$ at the applied voltage of 400Hz, 200V and increased to 420 cd/$\m^2$ with increasing the frequency to 30Hz. For the composite type devices, the threshold voltage was 45V and the maximum luminance was 670 cd/$\m^2$ at the driving condition of 200V, 30Hz. The value of luminance of the composite type device showed 1.5 times higher than that of stacking type device. The main emission peak was 512 nm of bluish-green color at 1Hz frequency below and shifted to 452 nm in the driving frequency over 5Hz showing the blue omission color. There were no distinct differences of the main emission peaks and color coordinate for both samples.

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Phase Equilibria and Processing of Pb_2Sr_2(Y_{1-x}Ca_x)Cu_3O_{8+\delta} Superconductors (x=0.4-0.6) (Pb_2Sr_2(Y_{1-x}Ca_x)Cu_3O_{8+\delta}초전도체 (x=0.4-0.6)의 제조방법 및 상평형)

  • Park, Young-il;Dongwoon Jung
    • Korean Journal of Materials Research
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    • v.5 no.6
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    • pp.723-731
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    • 1995
  • P $b_2$S $r_2$( $Y_{1-x}$ C $a_{x}$)C $u_3$ $O_{8+}$$\delta$/ samples were prepared with x=0.4~0.6 and small $\delta$. To minimize the extent of oxidative decomposition reaction which occurs during the preparation of this phase, two annealing steps were adopted : First, sintered samples of P $b_2$S $r_2$( $Y_{1-x}$ C $a_{x}$)C $u_3$ $O_{8+}$$\delta$/ are oxygenated under 100% $O_2$, which leads to a large $\delta$(e.g., $\delta$=1.8). Second, the resulting samples are deoxygenated under 0.1~1.0% $O_2$in $N_2$, lowering $\delta$ to desired values. This two-step annealing procedure minimized the extent of oxidative decomposition. However, even with the two-step annealing procedure, the oxidative decomposition of P $b_2$S $r_2$( $Y_{1-x}$ C $a_{x}$)C $u_3$ $O_{8+}$$\delta$/ cannot be completely suppressed if $\delta$ is to be reduced to maximize $T_{c}$. Electrical resistivity data show that $T_{c}$(onset) is a function of hole concentration in the Cu $O_2$layer, and the optimum hole concentration for the maximum $T_{c}$ is achieved when $Ca^{2+}$is substituted for $Y^{3+}$between 0.5 and 0.6 A $T_{c}$(onset)=80K has been observed for one such sample, and this is the highest $T_{c}$(onset) yet reported for this compound.ed for this compound.nd.

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Growth and Electrical Properties of Spinel-type ZnCo2O4 Thin Films by Reactive Magnetron Sputtering (반응성 때려내기 방법에 의한 스피넬 형 ZnCo2O4 박막의 성장과 전기적 물성)

  • Song, In-Chang;Kim, Hyun-Jung;Sim, Jae-Ho;Kim, Hyo-jin;Kim, Do-jin;Ihm, Young-Eon;Choo, Woong-Kil
    • Korean Journal of Materials Research
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    • v.13 no.8
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    • pp.519-523
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    • 2003
  • We report the synthesis of cubic spinel $ZnCo_2$$O_4$thin films and the tunability of the conduction type by control of the oxygen partial pressure ratio. Zinc cobalt oxide films were grown on$ SiO_2$(200 nm)/Si substrates by reactive magnetron sputtering method using Zn and Co metal targets in a mixed Ar/$O_2$atmosphere. We found from X-ray diffraction measurements that the crystal structure of the zinc cobalt oxide films grown under an oxygen-rich condition (the $O_2$/Ar partial pressure ratio of 9/1) changes from wurtzite-type $Zn_{1-x}$ $Co_{X}$O to spinel-type $ZnCo_2$$O_4$with the increase of the Co/Zn sputtering ratio,$ D_{co}$ $D_{zn}$ . We noted that the above structural change accompanied by the variation of the majority electrical conduction type from n-type (electrons) to p-type (holes). For a fixed $D_{co}$ $D_{zn}$ / of 2.0 yielding homogeneous spinel-type $_2$O$ZnCo_4$films, the type of the majority carriers also varied, depending on the$ O_2$/Ar partial pressure ratio: p-type for an $O_2$-rich and n-type for an Ar-rich atmosphere. The maximum electron and hole concentrations for the Zn $Co_2$ $O_4$films were found to be 1.37${\times}$10$^{20}$ c $m^{-3}$ and 2.41${\times}$10$^{20}$ c $m^{-3}$ , respectively, with a mobility of about 0.2 $\textrm{cm}^2$/Vs and a high conductivity of about 1.8 Ω/$cm^{-1}$ /.

Thermoelectric Properties of the 0.05wt% $SbI_3$-Doped n-Type $Bi_2({Te_{0.95}}{Se_{0.05}})_3$ Alloy with Variation of the Annealing Time (0.05wt% $SbI_3$를 첨가한 n형 $Bi_2({Te_{0.95}}{Se_{0.05}})_3$ 가압소결체의 열처리 시간에 따른 열전특성)

  • Lee, Sun-Kyong;Oh, Tae-Sung;Hyun, Dow-Bin
    • Korean Journal of Materials Research
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    • v.10 no.4
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    • pp.257-263
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    • 2000
  • Thermoelectric properties of the 0.05wt% $SbI_3$-doped n-type $Bi_2(Te_{0.95}Se_{0.05})_3$ alloy, prepared by melting/grinding and hot pressing, were investigated with variation of the annealing time up to 36 hours. The electron concentration of the 0.05wt% SbI$_3$-doped n-type $Bi_2(Te_{0.95}Se_{0.05})_3$ alloy decreased with increasing the annealing time. The figure-of-merit of the 0.05wt% $SbI_3$-doped n-type $Bi_2(Te_{0.95}Se_{0.05})_3$ alloy was improved from $2.1{\times}10^{-3}/K$ to $2.35{\times}10^{-3}/K$ by annealing at $500^{\circ}C$ for 3 hours. When annealed longer than 12 hours, however, the figure-of-merit decreased substantially due to the increase of the electrical resistivity.

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Interorder Hybridization between Pleurotus ostreatus and Elfvingia applanata by Protoplast Fusion (원형질체(原形質體) 융합(融合)에 의한 느타리버섯과 잔나비걸상버섯의 이목간(異目間) 교잡(交雜))

  • Yoo, Young-Bok
    • The Korean Journal of Mycology
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    • v.22 no.1
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    • pp.107-116
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    • 1994
  • Interorder somatic hybrids were obtained by protoplast fusion between Pleurotus ostreatus in the order Agaricales and Elfvingia applanata in the order Aphyllophorales. The fusants were classified into stable heterokaryons and spontaneously segregated heterokaryons. Hyphae of all fusion products except two strains did not form clamp connections. Out of them, two clamped and three clampless fusants produced mature fruiting bodies by light-dark cycle on sawdust rice bran medium. All of these basidiocarps had clamp connections. Three fusants were analysed with the distribution of progenies and segregation of genetic characters by random spore analyses. The genetic markers were shown to segregate and recombine in the first generation of monospores isolated from basidiocarps. Phenotypes of a large number of auxotrophic progenies were not detected in the two clamped fusants. The aberration ratio of segregants indicated the gene interaction resulting from different genome structure between distantly related species. The polymerase chain reaction (PCR) was adopted for the detection of somatic hybrids nuclear DNA. Four fusants showed a positive results in three kinds of primers. The prominent reaction products are represented by new bands in primer # 87 and # 125. Out of four fusants, two somatic hybrids had non-parental mtDNA patterns when digested with EcoR1 and HindIII. Comparison of somatic hybrids, tissue culture isolates(TC) and multispore germination isolates(MS) were made using esterase isozyme analysis. It is apparent that somatic hybrids had a minor banding patterns which are quite different from those of parents.

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Identity and Characteristics of Korean Pungsu(Fengshui) (한국 풍수론 전개의 양상과 특색)

  • Choi, Wonsuk
    • Journal of the Korean Geographical Society
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    • v.50 no.6
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    • pp.695-715
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    • 2015
  • The history of Korean Pungsu can be approached from two perspectives. One is through the history of its theoretical formation and evolution, and the other is through the history of its social and cultural formation and evolution. The former, i.e. Pungsu theories, was produced and developed by intellectuals as an elaborate system of cosmic knowledge and logic. The latter, i.e. Pungsu culture, was consumed and adopted by various social groups in their spatial life practices. It was Chinese intellectuals that originally initiated and carried out the production, formation, and development of the fengshui theoretical system. Intellectuals in neighboring countries adapted Chinese fengshui to their local environment, incorporating their own historical and cultural features, and practiced this transformed and indigenized form of geomancy. The evolution of Korean Pungsu can be summarized as having the following five characteristics. First, Koreans accepted fengshui from China, pragmatically adapting it to fit the Korean natural and social environment, and then used it for social discourse on space. Second, Pungsu had a comprehensive and varied influence on Korean culture throughout its different historical periods. Third, combined with social thought led by differing social classes, Korean Pungsu existed as an element of social discourse. Fourth, Koreans' theoretical preferences of fengshui were for the landform method over the liqi (理氣) method. Fifth, the Bibo philosophy was a characteristic feature of Korean Pungsu.

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Influence of Carbonation for Chloride Diffusion in Concrete (탄산화 복합환경시 염소이온 확산에 관한 연구)

  • Oh Byung-Hwan;Lee Sung-Kyu;Lee Myung-Kue;Jung Sang-Hwa
    • Journal of the Korea Concrete Institute
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    • v.17 no.2 s.86
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    • pp.179-189
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    • 2005
  • Corrosion of steel due to chloride attack is a major concern in reinforced concrete structures which are located in the marine environments. In this case, Fick's 2nd law has been used for the prediction of chloride diffusion related with service life of concrete structures. However, those studies were confined mostly to the single deterioration due to chloride only, although actual environment is rather of combined type. The purpose of the present study is, therefore, to explore the influences of carbonation to chloride attack in concrete structures and to investigate the validity of Fick's law to chloride attack combined carbonation. The test results indicate that the chloride ion profiles from Fick's law using the diffusion coefficient of immersion tests is not reflected the effect of separation of chloride ions in carbonation region but valid in sound region in case of combined action. On the other hand, the chloride ion profiles from Fick's law using the diffusion coefficient of Tang and Nilsson's method coincide with test results under dry-wet condition but not under combined condition. The results of present study may Imply that the new method for the measurement of diffusion coefficient is required to predict the chloride ion profiles in case of combined action at early.

Study on Decline of Trees by Acid Rainfall (산성 강우에 의한 수목의 쇠퇴현상(I) - 음이온을 중심으로 -)

  • Lee, Chong-Kyu;Hwang, Jin-Hyoung;Kim, Jong-Kab
    • The Korean Journal of Ecology
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    • v.27 no.6 s.122
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    • pp.347-353
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    • 2004
  • This study was carried out to analyze pH, Electrical conductivity(EC), cation and anion on rainfall and throughfall raining at industrial area(Onsan and Nongso of Ulsan city), suburban area(Myeongsek-myeon of Jinju city) and rural area(Haman and Changyoung-gun), and to investigate $SO_2\;and\;NO_2$ concentration in the air of industrial area and rural area, and to survey degree of decline of Pinus thunbergii growing at each area. The rainfall pH was higher than the throughfall pH at the all surveyed areas. The rainfall pH and throughfall pH was $4.76{\sim}5.15\;and\;4.64{\sim}4.98,\;4.95{\sim}5.30\;and\;4.87{\sim}5.13,\;5.29{\sim}5.76\;and\;5.12{\sim}5.73$ at the industrial area, suburban area and rural area, respectively. The EC of rainfall and throughfall was $13.64{\sim}17.22\;and\;41.60{\sim}103.59,\;4.18{\sim}8.65\;and\;17.02{\sim}23.89,\;4.09{\sim}6.65\;and\;13.75{\sim}21.44$ at the industrial area, suburban area and rural area, respectively. Generally EC at the industrial area was higher than those of suburban area and rural area. In the correlation analysis among Degree of decline on Pinus thunbergii and ingredients of rainfall, it showed that there was a negative correlation between Degree of decline and pH. There was a positive correlation between pH and $Cl^-$ respectively.