• Transactions on Electrical and Electronic Materials
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• 제14권3호
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• pp.125-129
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• 2013

Composites of platinum and multiwalled carbon nanotubes (MWNTs) were prepared in various reduction conditions and characterized using cyclic voltammetry. The MWNTs were functionalized with carboxylic acid and/or hydroxyl groups in acidic solutions prior to the formation of MWNT-Pt composites. Platinum nanoparticles were deposited onto the chemically-oxidized MWNTs in 1-propanol and 1,3-propanediol. The reduction of Pt precursors in other solutions could induce differences in their morphologies in composite thin films. The morphologies of MWNTs with Pt deposited were dependent on the reduction solutions, and the electrocatalytic activities on alcohols changed accordingly. The electrochemical activities of the as-prepared MWNT-Pt thin films on common alcohols such as methanol and ethanol were investigated.

• 대한의용생체공학회:의공학회지
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• 제12권1호
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• pp.57-62
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• 1991

ABA type block copolymers composed of poly($\gamma-benzyl$ L-glutamate) (PBLG) as the A component and poly (ethylene glycol) as the B component were obtained by polymerization of $\gamma-benzyl$ L-gletamate N -carboxyanhydride, initiated by amino groups at both ends of poly(ethylene glycol) . From circular dichroism measurements in ethylene dichloride solution as well as from infrared spectTa measurements in solid state, it was found that the polypep- tide block exists in the a-helical conformation, as in PBLG homopolymer. $Poly-N^5$ (3-hydroxypropyl glutamine) (PHPG)/poly(ethylene glycol)block copolymer hydrogel was obtained by the treatment of PBLG/PBG block copolymer with the mixture of 3-ammine-1-propanol and diamlnooctane. The water content of PHPG/PEG block copolymer hydrogel was about 80wt% when the concentration of crosslinking agent was below 5 mole % per polymer.

• Bulletin of the Korean Chemical Society
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• 제26권3호
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• pp.384-392
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• 2005

Solvent effects on the kinetics of bromophenol blue fading have been investigated within a temperature range in binary mixtures of methanol, ethanol, 1-propanol, ethylene glycol and 1,2-propanediol with water of varying solvent compositions up to 40% by weight of organic solvent component. Correlation of logk with reciprocal of the dielectric constant was linear. Finally a mechanism was proposed for the bromophenol blue fading upon SESMORTAC (study of effect of solvent mixture on the one-step reaction rates using the transition state theory and cage effect) model, by means of this model, the fundamental rate constants of the fading reaction in these solvent systems were calculated.

• Bulletin of the Korean Chemical Society
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• 제15권1호
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• pp.20-22
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• 1994

The preparation of $YBa_2Cu_4O_8$ thick film on Ag substrate by electrophoretic deposition was directly studied. Electrophoretic deposition was carried out in solution, which was composed of presintered $YBa_2Cu_4O_8$ powder, sodium, and 2-propanol as a solvent. The deposited thick films were heat-treated in $O_2$ at 815$^{\circ}$C for 12 hours and at 450$^{\circ}$C for 12 hours. We succeeded in obtaining superconducting $YBa_2Cu_4O_8$ films on Ag substrate. Even though the chemical reactions at the $YBa_2Cu_4O_8$/Ag interface occurred in the range of 10 ${\mu}$m, superconductivity was not depressed. The thickness of the films was in the range of 60-80 ${\mu}$ m. The characteristics of the films were examined by electric resistance measurements, X-ray diffraction, and SEM observations.

• Korean Chemical Engineering Research
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• 제59권2호
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• pp.219-224
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• 2021

Ion flotation is an efficient method to remove metal ions from aqueous solution. In this work, ion flotation was applied to calcium removal from aqueous solution. The parameters used included sodium stearate (SS) and sodium dodecyl sulfate (SDS) as collectors, 1-butanol and 1-propanol as frothers, pH, and air-flow rate. An L16 orthogonal array was chosen according to the mentioned factors and levels, and experimental tests were conducted according to the Taguchi orthogonal array. The results showed that all of the factors except one had significant effect on the flotation performance. The percentage contribution of parameters showed that type of frother and type of collector made the greatest (43.14%) and the lowest (9.86%) contribution, respectively. In optimal conditions, the recovery of Ca (II) ion was 45.67%. Also, the results illustrated that the Taguchi method could predict calcium removal from aqueous solution by ion flotation with 2.63%. This study showed that the use of ion flotation was an effective method for Ca (II) ion removal from aqueous solution.

• Mycobiology
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• 제49권3호
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• pp.201-212
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• 2021

Truffles are the fruiting bodies of ascomycete fungi that form underground. Truffles are globally valued, culturally celebrated as aphrodisiacs, and highly sought-after delicacies in the culinary world. For centuries, naturalists have speculated about their mode of formation, and in cultures surrounding the Mediterranean Sea, many species have been prized as a delectable food source. Truffle fruiting bodies form underground and emit a variety of volatile organic compounds (VOCs). Truffle volatiles are believed to have evolved to attract animals that disperse their spores. The main VOCs identified from truffles include sulfur compounds, such as dimethyl sulfide (DMS) and dimethyl disulfide (DMDS); in addition, 1-octen-3-ol and 2-methyl-1-propanol have been found in most truffle species. Humans use pigs and dogs trained to detect truffle VOCs in order to find these prized subterranean macrofungi. Truffles have pharmacological potential, but until more reliable cultivation methods become available their high price means they are unlikely to see widespread use as medicinals.

• 한국식품과학회지
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• 제47권5호
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• pp.579-585
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• 2015

유기산(acetic acid, citric acid, lactic acid)이 쌀 증류식 소주의 양조특성에 미치는 영향을 살펴보았다. 유기산 첨가에 의해서 술덧의 pH는 4.2에서 3.73-3.97, 산도는 5.06에서 8.13-9.98, 아미노산도는 2.56에서 2.27-2.34, 휘발산은 66.0에서 89.6-124.8 ppm으로 변하였다. 알코올 함량은 대조구는 17.8%, 첨가구는 각각 17.0, 17.8, 17.6%이었다. 술덧에 남아있는 acetic acid는 첨가된 양보다 증가한 반면 citric acid와 lactic acid는 첨가된 양보다 각각 1.30, 40.57% 감소되었다. pH변화에 의해 프로테이스 활성이 감소하였고 질소화합물 총량은 유기산 첨가에 의해서 각각 13.1, 36.9, 30.9% 감소하였다. 유리아미노산 중 alanine acid, arginine acid, glutamic acid가 질소화합물 총량의 10% 이상씩 함유되어 있었고 유기산 첨가에 의해서 methionine은 2.8-29.4%, cysteine은 12.5-30.8% 감소되었다. 첨가된 유기산은 증류효율에 영향을 미치지 않았으며 citric 및 lactic acid에 의해서 증류원액(알코올 함량 40%)의 TBA 값이 2.2-3.6배 낮아졌다. 알코올 함량이 25%로 조절된 소주의 isobutanol (B), isoamyl alcohol (A), 1-propanol (P) 함량의 합은 각각 1,041.47, 979.50, 961.48 ppm으로 대조구(935.27 ppm)보다 증가되었다. 유기산 첨가에 의해서 소주의 A/P비, A/B비, B/P비가 변하였으며 acetaldehyde 함량의 감소를 가져왔다.

• 한국식품영양과학회지
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• 제32권8호
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• pp.1206-1213
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• 2003

탁주의 기능성 강화를 위하여 율무를 첨가하여 제조한 탁주의 탁주로서의 적합성을 조사하였다. 우선 기존 쌀코오지를 이용하여 전분원으로서 율무를 15, 30, 60와 100% 첨가했을 경우, 효모의 균수와 ethanol의 생성량은 각각 9.5${\times}$$10^{7}$ ∼2.3${\times}$$10^{8}$ cell/mL과 13.6∼15.2%로 시료 간의 큰 차이를 보이지 않아 율무의 알콜 발효원으로 적합성을 보여주었다. 한편 고급알콜인 iso-amyl alcohol은 첨가된 율무량에 따라 1,150ppm으로부터 1,206, 1,213, 1,293, 1,604 ppm으로 각각 증가되고, acetaldehyde와 iso-butanol도 율무의 첨가량에 따라 증가하였다. 한편 Aspergillus kawachii(AK)와 ifhizopus japonicus(RJ)를 이용하여 율무누룩주를 만든 결과 ethanol 생성량은 쌀코오지로 만든 율무주에 비해 14%로부터 각각 11.2%(AK), 7.5%(RJ) 그리고 10.4%(AK+ RJ)로 감소하였고, 효모의 수는 7.5${\times}$$10^{7}$ ∼2.6${\times}$$10^{8}$ cell/mL이었으며, isoamyl alcohol 함량이 1,840 ppm으로부터 각각 632[AK], 855[RJ], 792 ppm[AK+RJ]로 감소하였고, n-propanol, iso-butanol 등의 fusel oil도 감소하였으나, acetaldehyde가 57ppm으로부터 99[AK], 138[RJ], 131 ppm[AK+RJ]으로 각각 증가되었다. 전체적으로 탁주제조에 있어 율무의 이용은, 전분원으로서 사용하는 경우 알콜 발효와 관능검사에는 큰 영향을 미치지 않았으나 fusel oil의 함량이 증가하였고, 누룩을 원료로서 사용하는 경우ethanol의 생성과 fusel oil의 생성이 감소하고, acetaldehyde의 함량이 현격히 증가하였으며, 관능검사 결과 기호도가 낮아졌다.

• 대한화학회지
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• 제39권4호
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• pp.237-243
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• 1995

Anthraquinone이 유기용매에서 광반으에 의하여 반응 중간체로 생성하는 짧은 수명의 중성 세미퀴논 라디칼과 음이온 라디칼을 시간분해 ESR법에 의하여 측정하였다. 2-2-propanol (PrOH)과 triethylamine (TEA) 10:1 혼합 용매에서 광반응에 의하여 생성하는 중성 anthrasemiquinone 라디칼(AQH${\cdot}$)과 음이온 라디칼 (AQH${\cdot}$)의 CIDEP 스펙트럼을 측정하였다. 생성한 AQH${\cdot}$은 반감기가 0.8 ${\mu}sec$로 수명이 아주 짧았으며, AQ${\cdot}$-은 안정하여 cwESR의 측정이 가능하였다. 스핀분극된 음이온 라디칼(AQ${\cdot}$-*)의 분극소멸 속도 상수는 $2.6{\times}10^5\; sec^{-1}$이고, 음이온 라디칼의 소멸은 1차 반응으로 속도상수가 $3.0{\times}10^2\; sec^{-1}$이다. 혼합용매에 TEA가 2% 미만일 때 CIDEP가 일어나지 않았다. 벤젠과 TEA 혼합용매에서는 반감기 3.0 ${\mu}sec$의 중성 anthrasemiquinone 라디칼의 CIDEP가 측정되었다. 그러나, cwESR은 측정되지 않았다. PrOH, TEA 또는 벤젠만의 용매로서는 CIDEP와 ESR을 측정할 수 없었다.

• 청정기술
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• 제20권2호
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• pp.146-153
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• 2014

본 연구에서는 입체장애 알카놀아민 첨가제인 2-아미노-2-메틸-1-프로판올(2-amino-2-methyl-1-propanol, AMP)과 2-아미노-2-메틸-1,3-프로판디올(amino-2-methyl-1,3-propanediol, AMPD)가 $K_2CO_3$ 흡수액의 이산화탄소 흡수속도와 $KHCO_3$ 고체염의 석출에 미치는 영향에 대해 고찰하였다. 흡수온도 $40^{\circ}C$와 $60^{\circ}C$에서 wetted-wall column을 이용하여 흡수속도와 이산화탄소 평형분압을 측정한 결과, 30 wt%의 고농도 $K_2CO_3$에 대해 5 wt% AMP와 AMPD는 흡수속도를 증가시키는 동시에 평형분압을 감소시켜, 흡수촉진제로서 흡수성능을 향상시키는 것으로 확인되었다. 또한, 회분식 냉각결정화 실험 결과, 복수의 히드록실기를 포함하는 AMPD가 흡수액을 냉각시 석출되는 $KHCO_3$ 고체염의 양을 증가시키는 것으로 나타났다.