• 제목/요약/키워드: organic cation

검색결과 489건 처리시간 0.026초

조계산 털조장나무군낙의 구조와 동태 (Structure and Dynamics of Lindera sericea Community in Mt. Chogye, Korea)

  • Kim, J. H.
    • The Korean Journal of Ecology
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    • 제20권1호
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    • pp.15-25
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    • 1997
  • The deciduous shrubs, Lindera sericea belonging to family Lauracea are distributed in Mt. Chogye and Mudeung locally. To estimate the community structure of this shrub, the relationship between the floristic composition and environmental factors of 20 sites in Mt. Chogye were investigated. L. sericea community distributed at the hum양 zone of altitude 305-480 m in ES and NE slope of $15~30^{\circ}$. The floristic composition of this communities consisted of 17-32 species varied with sites. Sasa borealis, Sapium japonicum, and Quercus serrata were the constant species over 90%. The forest vegetation was classified as Sasa borealis-Lindera sericea community, and the Sasa borealis-Meliosma oldhamii, and Sasa borealis-Callicarpa japonica were as subunit community. Acidity, organic matter content, inorganic phophate, potassium, calcium, magnesium, cation exchange capacity and conductivity were determined as environmental factors. Diameter of stem at ground surface and stem, distribution area and growth property of this plant were investigated, and this plant was presumed to be a relic endemic species.

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Agmatine Reduces Hydrogen Peroxide in Mesangial Cells under High Glucose Conditions

  • Lee, Geun-Taek;Ha, Hun-Joo;Lee, Hyun-Chul;Cho, Young-Dong
    • BMB Reports
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    • 제36권3호
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    • pp.251-257
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    • 2003
  • Agmatine, an amine and organic cation, reduced $H_2O_2$ that was generated by hyperglycemia, and transcription factors such as NF-${\kappa}B$ and AP-1 activity in the mesangial cells that were exposed to high glucose. However, spermine which shares a strong nucleophilic structure with agmatine decreased the $H_2O_2$ levels and AP-1, but not the NF-${\kappa}B$ activity. Possible roles for agmatine and spermine in decreasing fibronectin are discussed, and the signaling pathway for agmatine-reduced fibronectin accumulation is presented.

Treatment of organic dye solutions by electrodialysis

  • Majewska-Nowak, Katarzyna M.
    • Membrane and Water Treatment
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    • 제4권3호
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    • pp.203-214
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    • 2013
  • Laboratory tests were performed to determine the efficiency of dye solution desalination by electrodialysis. The study involved anionic dye and mineral salt recovery by obtaining two streams from a salt and dye mixture - dye-rich solution and salt solution. A standard anion-exchange and cation-exchange membranes or monovalent selective anion-exchange membranes were used in the ED stack. It was found that the separation efficiency was strongly dependent on the dye molecular weight. The best results for standard ion-exchange membranes were achieved for the desalination of Direct Black solution. Furthermore, the obtained results implied that the application of monovalent selective anion-exchange membranes improved the recovery of dye and salt solutions - the dye concentration in the diluate remained constant irrespective of the molecular weight of anionic dyes, whereas the salt recovery remained very high (99.5%).

고감도 비은염 화상재료 개발연구( I ) - CuPc안료의 승화정제 및 전해석출법에 의한 CuPc 박막의 제작과 전자사진감광체에의 응용 (A study of the High Sensitive Nonsilver Halide Imaging Material( I ) - Purification of CuPc pigment by a train sublimation technique and preparation of CuPc pigment thin films and it's application for electrophotoconductor -)

  • 이상남
    • 한국인쇄학회지
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    • 제8권1호
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    • pp.53-70
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    • 1990
  • It is well known that viologens such as 1.1 - disubstituted 4, 4` - bipyridinium salts and those used as redox indicator, herbicide and electrocheromic display device because those possess the lowest redox potential in any organic system. Viologen salts produced reversible high blue color under the influence of radical cation by photoreduction This study is related to the synthesis of viologen derivatives and the photoreduction property in water solution stats and the polar aprotic polyvinylpyrrolidone(PVP) matrix.

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한국(韓國) 경지토양특성(耕地土壤特性)에 관련(關聯)된 제초제(除草劑) 약해(藥害) (Herbicidal Phytotoxicity in Relation to the Korean Soil Properties)

  • 양환승;전재철
    • 한국잡초학회지
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    • 제2권2호
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    • pp.122-128
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    • 1982
  • This paper deals with herbicidal phytotoxicity which may occur because of unique properties of the Korean soils. Analysis of the Korean lowland and upland soils reveals that about 50% of the total area belongs to sandy loam and sandy gravel soils and most of both lowland and upland soils consists of kaolinite clay mineral. The chemical properties such as organic matter, pH, and cation exchange capacity show very low values by which there have been several instances of the herbicidal phytotoxicity occurred throughout the country. In addition, the paper emphasizes the need for selection and use of herbicides in the Korean soils.

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Polymer carrier 효과에 의하여 단순화된 새로운 세라믹분말 제조방법 (A preparation of dysprosium monotitanate powder by mixed-oxide ceramics processing employing polymer carrier)

  • 이상진
    • 한국결정성장학회지
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    • 제8권2호
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    • pp.350-355
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    • 1998
  • Ethylene glycol을 polymeric carrier로 사용한 새로운 화학적 세라믹 분말 제조 공정에 의하여 $(Dy_2TiO_5)$ 분말을 제조하였다. Chelation 공정의 생략에도 불구하고, 고순도의 미세한 입자를 갖는 세라믹 분말 제조가 가능함을 확인하였다. 열분석, 미세구조분석, 회절분석 등으로 분말특성을 평가하였다.

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이온성 액체를 이용한 수계 양자 점 합성 (Aqueous synthesis of quantum dots using functionalized ionic liquid)

  • 최숙영;김태영;서광석
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2010년도 하계학술대회 논문집
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    • pp.254-254
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    • 2010
  • We report aqueous synthesis of cadmium telluride (CdTe) quantum dots(QDs) using imidazolium-based ionic liquids with various functional groups. The functinalized ionic liquids were designed to have thiol groups, and then phase transfer with aqueous or organic solvents can be adjusted by changing side chain lengths of the cation and the choice of anion. The quantum yield was obtained IL-functionalized CdTe QDs reached up to 40% by post-treatment method.

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Platinum Transporters and Drug Resistance

  • Choi, Min-Koo;Kim, Dae-Duk
    • Archives of Pharmacal Research
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    • 제29권12호
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    • pp.1067-1073
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    • 2006
  • Cisplatin, a platinum coordinated complex, is a widely used antineoplastic agent for the treatment of metastatic tumors of the testis, metastatic ovarian tumors, lung cancer, advanced bladder cancer and many other solid tumors. The cytotoxic action of the drug is often thought to be associated with its ability to bind DNA to form cisplatin-DNA adducts. The development of resistance to cisplatin during treatment is common and constitutes a major obstacle to the cure of sensitive tumors. Although to understand the clinically relevant mechanisms of resistance, many studies have been aimed at clarifying the biochemical/molecular alterations of cisplatin-resistance cells, these studies did not conclusively identify the basis of cellular resistance to cisplatin. In this review, cisplatin resistance was discussed in terms of the relevant transporters, such as copper transporters (CTRs), organic cation transporters (OCTs) and multi-drug resistance related transporters (MDRs). These transporters seem to be contributed to cisplatin resistance through the reduction of drug accumulation in the cell. Better understanding the mechanism of cisplatin resistance associated with transporters will provide the useful informations for overcoming the cisplatin resistance.

Remedation of petroleum impacted filled land using of various in situ technology

  • 안훈기;김재형;고경연;서형기;임은진
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2004년도 임시총회 및 추계학술발표회
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    • pp.286-289
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    • 2004
  • On site, In situ soil remediation technologies are very important among the remediation technologies and in general efficiency of these technologies are turned to site characterization and environmental condition. specially using of only one technology has so many limitation factors. for example, existing state of tailing and channeling and so on. actually, filled land have high concentration cation exchange capacity because of existence in abundance soil organic matter. Therefore we used various on site in Situ technologies by phase for overcome the limitation factors. Target site is petroleum (diesel) impacted filled land and using technologies are SVE(Soil Vapor Extraction), BV(Bioventing), Bioremediation, Soil flushing, Chemical oxidation.

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Soil Properties in Two Forest Sites in Cox's Bazar, Bangladesh

  • Akhtaruzzaman, Md.;Osman, K.T.;Sirajul Haque, S.M.
    • Journal of Forest and Environmental Science
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    • 제31권4호
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    • pp.280-287
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    • 2015
  • Soil samples were collected from three depths (0-10 cm, 10-40 cm and 40-80 cm) of two forest sites including one plantation dominated by teak with some other minor species and another degraded natural forest in Cox's Bazar, Bangladesh to compare their soil properties. Some vegetation parameters were also studied. For this study $10{\times}10\;m$ and $2{\times}2\;m$ quadrats were used for the tree and undergrowth parameters, respectively. Soil samples were also collected from these quadrats. Between the two forest types, the highest levels of organic carbon, total nitrogen, available phosphorus, exchangeable bases and cation exchange capacity (CEC) were found in soils of the plantation. The soils were acidic in nature and exchangeable Al concentrations were low. Teak dominated forest plantation had higher soil fertility index (SFI) than the degraded natural forest site. Steps for reforestation and appropriate protection are needed to improve the situation.