• 약학회지
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• 제36권4호
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• pp.350-356
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• 1992

Anticoagulant activities were tested for the fifteen kinds of medicinal plants by measuring activated partial thromboplastin time (aPTT). Of them five kinds or species (Artemisia princeps, Sanguisorba officinalis, Artemisia apiacea, Eclipa alba, Schizonepeta tenuifolia) were selected and fractionated for the preparation of acidic polysaccharides. They were extracted with water by refluxing and the extracts were precipitated with ethanol. The precipitates were separated based on charge using a DEAE-Sephadex. The low salt and high salt fractions were sulfated with anhydrous pyridine and chlorosulfonic acid complex. In vitro anticoagulant activities of sulfated polysaccharides were tested by measuring aPTT, prothrombin time (PT), and factor Xa clotting time using normal human plasma. No relationship was found between the amount of uronic acids and anticoagulant activities, but the sulfated ones show the increase of activities. In vivo anticoagulant properties of the sulfated polysaccharide from Artemisia apiacea were also tested by the intraveneous administration of three different doses (3,5 and 10 mg/kg) to rats. APTT and PT were increased significantly and the action of factor Xa and thrombin mediated through antithrombin III were inhibited slightly.

• Membrane and Water Treatment
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• 제1권4호
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• pp.231-251
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• 2010

The sulfatation of chitosan, by reaction with chlorosulfonic acid under controlled conditions, allowed increasing the pH range of chitosan solubility. The biopolymer was characterized using FTIR and $^{13}C$-NMR spectroscopy, elemental analysis and titration analysis and it was tested for mercury recovery by polymer enhanced ultrafiltration (PEUF). In slightly alkaline conditions (i.e., pH 8) mercury recovery was possible and at saturation of the polymer the molar ratio $-NH_2$/Hg(II) tended to 2.6. Polymer recycling was possible changing the pH to 2 and the polymer was reused for 3 cycles maintaining high metal recovery. The presence of chloride ions influences metal speciation and affinity for the polymer and "playing" with metal speciation allowed using the PEUF process for mercury separation from cadmium; at pH 11 the formation of hydroxo-complexes of Hg(II) limits it retention. Cake formation reveals the predominant controlling step for permeation flux.

• 센서학회지
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• 제30권6호
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• pp.357-363
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• 2021

We developed a chemiresistive anion sensor using highly conductive carbon nanotube fibers (CNTFs) functionalized with anion receptors. Mechanically robust CNTFs were prepared via wet-spinning utilizing the nematic liquid crystal properties of CNTs in chlorosulfonic acid (CSA). For anion detection, polymeric receptors composed of dual-hydrogen bond donors, including thiourea 1, squaramide 2, and croconamide 3, were prepared and bonded non-covalently on the surface of the CNTFs. The binding affinities of the anion receptors were studied using UV-vis titrations. The results revealed that squaramide 2 exhibited the highest binding affinity toward AcO^-, followed by thiourea 1 and croconamide 3. This trend was consistent with the chemiresistive sensing responses toward AcO^- using functional CNTFs. Selective anion sensing properties were observed that CNTFs functionalized with squaramide 2 exhibited a response of 1.08% toward 33.33 mM AcO^-, while negligible responses (<0.1%) were observed for other anions such as Cl^-, Br^-, and NO₃^-. The improved response was attributed to the internal charge transfer of dual-hydrogen bond donors owing to the deprotonation of the receptor upon the addition of AcO^-.

• 멤브레인
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• 제12권4호
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• pp.247-254
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• 2002

직접메탄올연료전지에 사용가능한 이온교환막을 개발하기 위하여 본 연구에서는 폴리설폰을 설폰화시켜 양이온교환막을 제조하였고 그에 대한 특성을 $150^{\circ}C$에서 열처리 전과 후를 통해 메탄을 투과도, 이온전도도, 이온교환용량 그리고 함수율 등에 대하여 평가하였다. 폴리설폰 고분자의 단량체와 설폰화제의 몰비가 1.4일 때 메탄올 투과도는 $2.87{\times}10^{-7} \;cm^2/s$(열처리 안함), $1.52{\times}10^{-7}\; cm^2/s$(열처리함)과 이온전도도는 1.10{\times}10^{-2}\; S/cm$ (열처리안함), 0.87{\times}10^{-2}\; S/cm$(열처리함)을 각각 보여 주었다. 그 이후의 몰비에서는 거의 증가하지 않았으며, 이러한 경향은 함수율과 이온교환용량에서도 같은 경향을 보여주었다.

• 폴리머
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• 제25권5호
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• pp.642-648
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• 2001

암모니아 흡착제를 제조하기 위하여 먼저 광(자외선)조사법으로 스티렌을 폴리프로필렌 부직포에 그라프트 중합시키고, 이를 술폰화한 다음에 금속이온과 반응시켜 금속 착체를 제조하였다. 스티렌 농도가 증가할수록 그라프트율은 증가하였으며, 반응시간이 길어질수록 그라프크율은 증가하였다. 한편 제조된 각종 시료의 암모니아 흡착 능력은 치환된 술폰산기의 함량, 흡착시판 및 암모니아 기체 압력이 증가할수록 증가하였으며, 술폰산기의 함량이 4.25 mmol $H^+$/g인 시료의 경우에 6.51 mmol/g의 흡착량을 나타내었다. 금속이온을 착물로 한 시료는 착물화 전의 시료에 비해 흡착능이 우수하였으며, $cO^{+2}$를 착물로 한 경우에 9.90mmo1/g의 암모니아 흡착능을 나타내어, 기존의 활성탄이나 실리카겔보다 효과가 우수하였다.

• Journal of Microbiology and Biotechnology
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• 제21권10호
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• pp.1036-1042
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• 2011

The exopolysaccharide botryosphaeran ($EPS_{GLC}$; a ($1{\rightarrow}3$)($1{\rightarrow}6$)-${\beta}$-D-glucan from Botryosphaeria rhodina MAMB-05) was sulfonated to produce a water-soluble fraction ($EPS_{GLC}$-S) using pyridine and chlorosulfonic acid in formamid. This procedure was then repeated twice to produce another fraction ($EPS_{GLC}$-RS) with a higher degree of substitution (DS, 1.64). The purity of each botryosphaeran sample (unsulfonated and sulfonated) was assessed by gel filtration chromatography (Sepharose CL-4B), where each polysaccharide was eluted as a single symmetrical peak. The structures of the sulfonated and re-sulfonated botryosphaerans were investigated using ultraviolet-visible (UV-Vis), Fourier-transform infrared (FT-IR), and $^{13}C$ nuclear magnetic resonance ($^{13}C$ NMR) spectroscopies. $EPS_{GLC}$ and $EPS_{GLC}$-RS were also assayed for anticoagulation activity, and $EPS_{GLC}$-RS was identified as an anticoagulant.