• 펄프종이기술
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• 제47권3호
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• pp.11-17
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• 2015

In acid hydrolysis process of biomass saccharification. neutralization of acid hydrolyzate is essential step, which resulted in dissolved cations in glucose solution. Impact of cations to Kluyveromyces marxianus in glucose solution was investigated focused on ethanol fermentation. Either potassium or sodium cations decreased the ethanol fermentation and glucose to ethanol conversion. Glucose consumption by K. marxianus was delayed by increasing potassium cation concentration as completely consumed within 12 h in potassium cation 0.46 mol and 0.92 mol but within 24 h in potassium cation 1.38 mol. Also, ethanol fermentation process was slowed down with increasing concentration of the potassium sulfate. Fermentation of glucose solution to ethanol was more inhibited by sodium cation than potassium cation in glucose solution. Glucose was completely consumed within 24 h in sodium cation 0.95 mol. but at 1.90 mol or 2.84 mol in sodium cation could not finish the fermentation within 48 hour. Ethanol concentration was 22.26 g/L at low sodium cation in glucose solution with complete fermentation within 24 h. With increasing sodium cation in glucose solution, final ethanol concentration was reached at 14.10 g/L (sodium cation con) and 0.21 g/L (sodium cation con), which meant delaying of fermentation by sodium cations.

• 펄프종이기술
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• 제47권1호
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• pp.17-23
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• 2015

In bioethanol from acid hydrolysis process, neutralization of acid hydrolyzate is essential step, which resulted in dissolved cations in glucose solution. Impact of cations to Saccharomyces cerevisiae in glucose solution was investigated focused on ethanol fermentation. Both potassium and sodium cations decreased the ethanol fermentation and glucose to ethanol conversion as potassium or sodium cations. In sodium cation, more than 1.13 N sodium cation in glucose solution led to ethanol production less than theoretical yield with severe inhibition. In 1.13 N sodium cation concentration, ethanol fermentation was slowed down to reach the maximum ethanol concentration with 48 h fermentation compared with 24 h fermentation in control (no sodium cation in glucose solution). In case of potassium cation, three different levels of potassium led to silimar ethanol concentration even though slight slow down of ethanol fermentation with increasing potassium cation concentration at 12 h fermentation. Sodium cation showed more inhibition than potassium cation as ethanol concentration and glucose consumption by Saccharomyces cerevisiae.

• Food Science and Biotechnology
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• 제14권1호
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• pp.108-111
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• 2005

To improve water-resistance and physical properties of sodium alginate film, effects of sodium alginate and plasticizer concentrations, divalent cation types and concentrations, and immersion time of films into divalent cation solutions on sodium alginate films were evaluated, based on elongation strength (ES), elongation rate (E), water vapor permeability (WVP), and water solubility (WS). Film made from 1.5% sodium alginate solution (w/w) had low WVP and WS, which are optimal characteristics for application of film preparation. Addition of plasticizer increased E and WS. Less than 2% $CaCl_2$ addition and 15min immersion time reduced WVP, WS, and E significantly (p<0.05). Sodium alginate films treated with $CuCl_2$, and $ZnCl_2$ solutions had lower WVP and WS, whereas $MgCl_2$ had no influence on improving water resistance of films.

• Bulletin of the Korean Chemical Society
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• 제2권1호
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• pp.24-28
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• 1981

Theoretical studies of the sodium cation binding and the isotope hydration effects on the static model compound B-DNA have been qualitatively elucidated by using empirical potential energy functions. In the first place, the sodium cations bound to phosphate anions and their hydration scheme have been optimized and have given a reasonable agreement with other theoretical results and experimental studies. In the second stage, the isotope effect on the hydration through the substitution of $D_2O\;for\;H_2O$ has been carried out by the same procedure. The stabilization of B-DNA has been explained and compared in terms of the sodium cation binding to phosphate anions and its hydration in both cases of $H_2O\;and\;D_2O$.

• 공업화학
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• 제8권1호
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• pp.67-75
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• 1997

LLDPE와 미분말 상태인 강산성 양이온 교환 수지를 사용하여 압출기를 통해 막상으로 성형한 후 증류수와 NaCl 포화 수용액상에서 후처리하여 불균질 양이온 교환막을 제조하고 특성화하였다. 증류수 및 NaCl 포화 수용액 중에서 후처리를 통하여 양이온 교환 수지 입자가 함수, 팽윤되어 폴리에틸렌과 이온 교환 수지 사이에 cavity가 발생하며 동시에 양이온 교환 수지의 팽윤 압력에 의해 결합제에 큰 힘이 작용하기 때문에 폴리에틸렌에 micro-crack이 생성되므로 전기 화학적, 물리적 특성 값이 향상되었다. 또한 후처리 시간 30분과 후처리 온도 $90^{\circ}C$에서 최적의 조건을 갖는 우수한 불균질 양이온 교환막이 제조되었다.

• 한국토양비료학회지
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• 제6권3호
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• pp.193-197
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• 1973

1. 두 다년생(多年生) 사막식물(沙膜植物) (Lycium andersonii, Atriplex confertifolia)이 Na($NO_3{^-}$, $Cl^-$, $H_2PO_4{^-}$)의 다른 기원으로 식물체내(植物體內) cation-anion 균형에 대(對)한 영향을 평가하기 위해 온실에서 토양재배(土壤裁培)를 하였다. 2. 각(各) anion은 다른 anion과 상호작용(交互作用)이 있을지라도 시비(施肥)에 따라 주(主)로 엽(葉)에 증가되였다. 3. 측정(測定)된 전(全) anion(N. P. Cl)은 각(各) 식물(植物) 부분(部分)에 증가되였다. 4. 동시에 전(全) cation도 증가현상을 보였다. 5. Cation-action의 비율은 $NaNO_3$의 경우 현저(顯著)히 감소(減少)되였다. cation-anion 비율(比率)은 보통 1을 넘고 있다. 6. 염내(鹽內) Cl 및 N의 최고(最高) 함량은 이들 성분(成分)이 부여(附加)될 때 Lycium andersonii에서 13.51% 및 6.37%로 각각(各各) 나타나고 있다. 7. Na 농도(濃度)는 Lycium andersonii 보다 Atriplex confertifolia 에서 더 높았다. 8. Na의 각 처리간에 유의차가 있을지라도 전(全) cation은 일정(一定)하게 유지(維持)되는 것으로 봐 처리구(處理區)에서 Na가 증가 됨으로서 다른 Cation들 사이에 약간의 보상작용(補償作用)이 나타났다. 9. Lycium andersonii는 Li의 축적자(蓄績者)로 나타나고 있다.

• 한국염색가공학회지
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• 제13권2호
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• pp.114-119
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• 2001

Four kinds of neutral sodium salts with different anions, NaF, NaCl, NaBr, and NaI, were added to the dye bath to accurately understand the effect of anions on the reactive dyeing of silk with C. I. Reactive Black 5. The sodium cation towered the negative surface potential of the silk and increased the dye-uptake on fille fabric as reported previously. However, because of the discrepancy in the anions'inhibition power from cation's lowering: the surface negative potential the amount of the dye on the silk fiber was different from each other in the order of $F^->Cl^-> Br^-I^-$. The activation energy(E$_{a}$) lot the dyeing was in the order of $F^->Cl^-> Br^-I^-$ but the dye-uptake on the fabric and the activation free energy$(\Delta{G}^*)$, the real energy barrier fort the reaction, were in the order of $F^->Cl^-> Br^-I^-$ because the strength of the interaction of the anions with sodium cations was the salute as the order of the latter. In other words F$^{[-1000]}$ exerted the weakest electrostatic force on $Na^+$ and competed with the dyestuff anions least of all. The decrease in $\Delta{S}^*$ may be due to the looesly bonded activated complex of dyestuff anions, sodium cations and fiber molecules at transition state. It was clarified from the Brёnsted equation that sodium salts with different anions also had fille ionic strength effect and the specific salt effect on the reactive dyeing.g.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2017년도 춘계학술대회 논문집
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• pp.151.2-151.2
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• 2017

본 연구에서는 정전류 조건에서 알루미늄 합금의 PEO(Plasma Electrolytic Oxidation) 피막 형성 거동에 미치는 전해질 내 cation($K^+$, $Na^+$)의 영향을 아크 발생 양상, 전압-시간 곡선 및 형성된 표면피막 구조를 관찰하여 연구하였다. 전해질은 0.5 M NaOH + 1 M $Na_2SiO_3$ 수용액과 0.5 M KOH + 1 M $Na_2SiO_3$ 수용액이 사용되었다. 아크 발생은 cation의 종류에 상관없이 동일하게 가장자리부터 시작되어 내부로 이동함으로써 전 표면에 걸쳐서 일어났다. 전 표면에서 PEO 피막이 형성된 이후에는 한 지점에서 지속적으로 아크가 발생하는 로컬버닝 현상이 두 용액에서 모두 관찰되었으나 $K^+$이온이 포함된 용액에서 로컬버닝이 빠르게 일어났다. 시편표면에서 아크가 발생하는 동안 중 각 전해액에서의 전압-시간 곡선에서 전압의 상승과 하강이 반복되는 거동이 동일하게 관찰되었다. 이러한 전압 등락의 크기는 $K^+$ 이온이 포함된 수용액에서 더 크게 나타났으며, 그 결과 표면 거칠기가 상대적으로 더 높은 PEO 피막이 형성되었다.

• Bulletin of the Korean Chemical Society
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• 제30권9호
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• pp.1996-2000
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• 2009

Alkali metal salts were introduced to enhance the ionization efficiency of glucose and maltooligoses in electrospray ionization-mass spectrometry (ESI-MS). A mixture of the same moles of glucose, maltose, maltotriose, maltotetraose, maltopentaose, maltohexaose, and maltoheptaose was used. Salts of lithium, sodium, potassium, and cesium were employed as the cationizing agent. The ionization efficiency varied with the alkali metal cation types as well as the analyte sizes. Ion abundance distribution of the [M+$cation]^+$ ions of the carbohydrates varied with the fragmentor voltage. The maximum ion abundance at low fragmentor voltage was observed at maltose, while the maximum ion abundance at high fragmentor voltage shifted to maltotriose or maltotetraose for Na, K, and Cs. Variation of the ionization efficiency was explained with the hydrated cation size and the binding energy of the analyte and alkali metal cation.

• 분석과학
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• 제13권4호
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• pp.466-473
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• 2000

용매고분자막 상에 칼륨과 다양한 나트륨이온 선택성 중성 운반체의 착물형성상수(${\beta}_{MLn}$)를 고분자막형 광센서(optode)와 이온선택성 전극(ISE)을 이용하여 결정하였다. 수소이온선택성 발색물질(chromoionophore : ETH 5294)에 가장 널리 쓰이는 나트륨 이온선택성 물질들(4-tert-butylcalix[4]arenetetraacetic acid tetraethyl ester, ETH 2120, bis[(12-crown-4)methyl] dodecyl-methylmalonate 및 monensin methyl ester)을 첨가한 막과 첨가하지 않은 막으로 두 가지 다른 조성의 PVC 막을 제작하여, 일정 pH(0.05 M Tris-HCl, pH7.2)에서 알칼리금속 양이온(나트륨과 칼륨)의 농도 변화에 따른 광학적 감응을 측정하고, 또 일정한 알칼리금속 양이온 농도(0.1M)에서 pH변화에 따른 광학적 감응을 측정하였다. 또한 유사한 조성의 막을 각각 재래식 전극체에 장착하고 일정한 알칼리금속 양이온의 농도(0.1M)에서 pH 변화에 따른 전위치를 측정하였다. 양이온/수소이온의 활동도 비($a_{M^+}/a_{H^+}$)와 상대흡광도로 도시한 광센서 감응곡선과 수소이온농도에 따른 전위차 감응곡선으로부터 나트륨 이온선택성 리간드들의 착물형성상수를 결정하였다. 목적이온과 방해이온에 대한 착물형성상수들의 비로부터 얻어진 값은 실험적으로 얻어진 이온선택성 전극의 선택계수와 근접함을 확인하였다.