• Bulletin of the Korean Chemical Society
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• 제22권1호
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• pp.103-106
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• 2001

• Bulletin of the Korean Chemical Society
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• 제19권2호
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• pp.197-201
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• 1998

The complex formation from Cu(Ⅱ) ion and 1,3-bis(tris(hydroxymethyl)methylamino)propane (bistrispropane) in aqueous solution has been studied potentiometrically and spectrophotometrically. Bistrispropane (btp) coordinates to Cu(Ⅱ) as multidentate. In the btp (L) complex CuL2+, two of the hydroxyl oxygen atoms as well as the amine nitrogens of the ligand are coordinated. In neutral and weakly acidic media, one of the coordinated hydroxyl groups is deprotonated. In basic media, an additional hydroxyl group undergoes deprotonation. The equilibrium constants for the formation of CuL2+, CuLH-1+, and CuLH-2 have been determined. The nature of the coordinate bonds has been deduced from the potentiometric data and the spectra of these complexes.

• 접착 및 계면
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• 제8권2호
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• pp.9-14
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• 2007

본 연구에서는 poly(ethylene glycol) (PEG), isophoron diisocyanate (IPDI), 1,1,1-tris(hydroxymethyl)propane (THMP) 등을 사용하여 polyurethane microgel을 합성하였다. Microgel이 형성될 수 있는 조건들을 측정하였으며, 전자현미경 (SEM), 입자크기 측정기 등을 이용하여 형성된 microgel의 형태 및 물성들을 알아보았다. 사용한 PEG의 양이 THMP에 비해 비교적 많을 때에만 microgel이 형성되었으며, 따라서 PEG가 microgel의 형성에 매우 중요한 역할을 하고 있음을 알 수 있었다. Microgel의 형성 과정 중에 측정한 microgel 용액의 점도는 microgel의 형성과 더불어 감소하였다. 사용한 PEG의 분자량은 2,000, 6,000, 10,000이었는데 분자량이 6,000인 것을 사용하였을 때, microgel이 가장 잘 얻어졌다. 형성된 microgel의 크기를 입자크기 측정기로 측정하였더니 130~230 nm 정도였다.

• 한국응용과학기술학회지
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• 제13권3호
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• pp.61-71
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• 1996

In acid-catalyzed acetal cyclization of long aliphatic aldehydes($R=n-C_7H_{15}$ ; $n-C_9H_{19}$ ; $n-C_{11}H_{23}$) with 1,1,1-tris(hydroxymethyl)propane, 2-alkyl-5-hydroxymethyl-5-ethyl-1,3-dioxanes were obtained. The final products, sodium 2-alkyl-5-(sulfonatedpropylethermethyl)-5-ethyl-1,3-propanesultion in the presence of sodium hydride. These compounds were a new group of destructible surfactants which were readily hydrolyzed and oxidized in natural water reservoirs. Physical properties of these new compounds involved some surface properties such as Krafft point(Kp), critical micelle concentration(cmc), surface tension of aqueous solutions near cmc(${\gamma}_{min}$), foaming power, emulsion power and hydrolysis properties were determined. The destructible surfactants containing 1,3-dioxane ring were synthesized to about $85{\pm}5.5%$ yield. The cmc values of the compounds by ring method were assumed to $0.5{\sim}5.0{\times}10^{-3}mol/L$ range and surface tensions at cmc were $29.5{\sim}33.0dyne/cm$ respectively at $25^{\circ}C$. The foaming power and foam stability were $170{\sim}230mm$ and $52{\sim}135mm$ respectively at $1{\times}10^{-2}mol/L$, foam was occurred rarely below $1{\times}10^{-3}mol/L$. The emulsion property of liquid paraffin was better than that of soybean oil. For hydrolysis property with ph and time, these compounds were decomposed within about 200minutes at $ph1{\sim}2$. Hopefully these compounds are expected to be a good O/W emulsifier that have decomposability in acid and may be used in the process which do not need foaming.

• Bulletin of the Korean Chemical Society
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• 제24권7호
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• pp.943-947
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• 2003

We have studied the migration behavior of single-stranded DNA using capillary gel electrophoresis under various conditions. It was found that optimum electric fields should be less than 150 V/cm for the good tradeoff between the separation time and the resolution. It seems that the gel matrix with the combination of different polymer average molecular weights is important to extend the maximum readable DNA bases. The total gel concentration less than 3.1% in the mixed gel system showed good separation efficiency up to 600 bases. The best result was obtained with the poy(ethylene)oxide (PEO) gel concentration of 1.2% of Mr 8,000,000 and 1.8% of Mr 600,000. We observed that the capillary length between 50 cm to 100 cm (effective length) should be employed for the optimization between the total DNA migration time and the maximum readable length. A trizma base-boric acid-ethlyenediaminetetraacetic acid (EDTA) (TBE) buffer was commonly used for DNA sequencing, but we found that 3-[tris(hydroxymethyl)methyl amino]-1-propane sulfonic acid (TAPS) buffer worked as well for the single-stranded DNA separation. Especially, TAPS buffer showed a good resolution for very short DNA bases (1 to 30 bases).