• 대한환경공학회지
• /
• 제35권1호
• /
• pp.70-73
• /
• 2013

토양정화를 위한 토양 세정 및 세척 공정에서 계면활성제 선택 기준과 가장 중요한 설계인자는 오염물질의 용해도이다. 계면활성제의 오염물질 용해도는 오염물질과 평형상태를 만든 후 Dichrolomethane을 이용한 추출, 증발, 농축 등의 전처리과정을 거쳐야 한다. 따라서 계면활성제 용액 내 유류 오염 물질의 용해도 분석은 많은 시간과 재료를 필요로 한다. 계면장력은 계면활성제용액과 유류오염물질 사이에 유지되는 힘을 지칭하는 것으로 용해도와 밀접한 관계를 가진다. 본 연구는 계면활성제용액과 경유 간 계면장력과 용해도를 측정하여 계면장력과 용해도간 상관관계를 정립하므로 신속한 계면 장력 측정을 통한 용해도를 가늠할 수 있는 방안을 제시하였다. 계면장력과 유류용해도간 상관관계를 평가한 결과 두 특성은 기하급수적인 반비례관계를 보였다. 즉, 계면장력이 5 dyne/cm 이상조건에서 경유의 용해도는 크게 차이를 보이지 않다가 1 dyne/cm 이하에서 경유의 용해도는 급격하게 증가하였다. 앞으로 계면활성제용액 간 계면장력을 우선적으로 측정해 본다면 토양정화에 적합한 계면활성제 종류 및 농도를 매우 신속하고 효율적으로 선택할 수 있을 것으로 판단된다.

• 한국식품과학회지
• /
• 제22권3호
• /
• pp.343-349
• /
• 1990

pH를 달리한 수용액 및 농도를 달리한 염류수용액에서 들깨종실의 단백질과 phytate의 용해도를 측정하여 단백질로부터 phytate를 제거할 수 있는 조건을 검토하였다. 들깨종실단백질의 용해도는 pH4.0에서 가장 낮은 9.5%로 등전점을 보였고, 그보다 산성 또는 알칼리성쪽으로 갈수록 증가되었다. 반면에 phytate의 용해도는 pH5.0에서 가장 높았으며 그보다 산성 또는 알칼리성쪽으로 갈수록 감소되었다. NaCl 수용액을 처리하였을 때 단백질의 용해도는 pH $3.0{\sim}4.0$ 범위에서 가장 낮았고 pH 6.0 이상에서는 현저히 증가되었다. Phytate의 용해도는 pH$2.0{\sim}5.0$ 범위에서는 약 90%내외로 높았으나 pH6.0 이상에서는 급격히 감소되었다. $Na_2SO_3$ 수용액처리에서는 단백질 용해도가 $pH2.0{\sim}3.0$ 범위에서 가장 낮았고 phytate의 용해도는 $pH5.0{\sim}6.0$에서 최대치를 보였고, 3%의 경우는 전 pH 구간에 걸쳐서 낮았으나 5%와 7%에서는 전 구간에서 높았다. $CaCl_2$ 수용액처리에서는 단백질 용해도가 3% 수용액에서는 전 pH 구간에서 낮았으나 5%와 7%에서는 $pH5.0{\sim}10.0$에서 높은 값을 보였으며 phytate의 용해도는 $pH2.0{\sim}3.0$ 사이에서 최대값을 나타내고 pH4.0이상에서는 급격히 감소하였다. 이상의 결과에서 3% NaCl 용액을 사용하여 pH9.0에서 단백질을 추출하고 pH4.0에서 침전시켰을 때 단백질 수율이 좋고 phytate 잔존량이 가장 적어, 저(低)phytate 분리단백질을 만드는 가장 좋은 조건이었다..

• 대한화학회지
• /
• 제53권4호
• /
• pp.453-465
• /
• 2009

본 연구에서는 한 가지 염으로 포화된 수용액에 다른 염을 녹이면 얼마나 녹을 것인가에 대한 초-중등 학생들과 교사들의 이해 정도가 낮은 이유를 알아보기 위하여 중등학교 교과서와 대학교 교재의 서술 내용을 조사하였다. 그 결과 중등학교 교과서와 대학교 일반화학 교재에서는 다른 염의 존재 여부와 상관없이 용해도는 일정함을 전제로 서술하고 있었으며, 대학교 물리화학 교재에서는 다른 염의 존재에 의해 용해도가 달라짐을 직접 언급하거나 이를 알 수 있는 내용이 서술되어 있었다. 그러나 물리화학을 이수한 사범대학 4학년 학생들을 대상으로 조사해본 결과 학생들의 대부분이 이러한 용해도 변화에 대한 설명을 하지 못하였다. 따라서 교사나 예비 교사들의 의문을 해소하기 위해 이온쌍 형성과 이온 세기 변화에 따른 용해도의 변화를 설명하고, 실제 실험 결과도 하나 제시하였다. 하지만 중등학교에서는 활동도 개념의 도입이 어려우므로 두 가지 염이 동시에 용해될 때의 용해도를 어떻게 가르칠지에 대한 논의가 필요한 것으로 생각된다.

• Asian-Australasian Journal of Animal Sciences
• /
• 제29권8호
• /
• pp.1159-1165
• /
• 2016

The nutritional value of feed proteins and their utilization by livestock are related not only to the chemical composition but also to the structure of feed proteins, but few studies thus far have investigated the relationship between the structure of feed proteins and their solubility as well as digestibility in monogastric animals. To address this question we analyzed soybean meal, fish meal, corn distiller's dried grains with solubles, corn gluten meal, and feather meal by Fourier transform infrared (FTIR) spectroscopy to determine the protein molecular spectral band characteristics for amides I and II as well as ${\alpha}$-helices and ${\beta}$-sheets and their ratios. Protein solubility and in vitro digestibility were measured with the Kjeldahl method using 0.2% KOH solution and the pepsin-pancreatin two-step enzymatic method, respectively. We found that all measured spectral band intensities (height and area) of feed proteins were correlated with their the in vitro digestibility and solubility ($p{\leq}0.003$); moreover, the relatively quantitative amounts of ${\alpha}$-helices, random coils, and ${\alpha}$-helix to ${\beta}$-sheet ratio in protein secondary structures were positively correlated with protein in vitro digestibility and solubility ($p{\leq}0.004$). On the other hand, the percentage of ${\beta}$-sheet structures was negatively correlated with protein in vitro digestibility (p<0.001) and solubility (p = 0.002). These results demonstrate that the molecular structure characteristics of feed proteins are closely related to their in vitro digestibility at 28 h and solubility. Furthermore, the ${\alpha}$-helix-to-${\beta}$-sheet ratio can be used to predict the nutritional value of feed proteins.

• Journal of Pharmaceutical Investigation
• /
• 제33권1호
• /
• pp.45-49
• /
• 2003

The solubility and stability of ondansetron hydrochloride (OS) in various vehicles were determined. The effect of cyclodextrins (CD) on the solubility of OS in water was determined by equilibrium solubility method. The solubility of OS at $32^{\circ}C$ increased in the rank order of isopropyl myristate (IPM) < propylene glycol laurate (PGL) ${\ll}$ propylene glycol monolaurate < propylene glycol monocaprylate (PGMC) < poly(ethylene glycol) 400 < diethylene glycol mono ethyl ether (DGME) < ethanol < poly(ethylene glycol) 300 < water (36.1 mg/ml) ${\ll}$ propylene glycol (PG) (283 mg/ml). The addition of PG or DGME to non-aqueous vehicles such as IPM, PGL and PGMC markedly increased the solubility of OS. The addition of CDs in water increased the solubility. Apparent stability constant for the CD complexation with OS was calculated to be $25.5\;M^{-1}$ for $2-hydroxypropyl-{\beta}-CD\;(2HP{\beta}CD)$. Twenty mM ${\beta}-CD$, 69.4 mM sulfobutyl ether ${\beta}-CD$ and 115.4 mM $2HP{\beta}CD$ increased the aqueous solubilty of OS 1.27, 2.18 and 1.85 times, respectively. OS was stable in buffered aqueous solution (pH 5.0). However, OS was relatively unstable in non-aqueous vehicles in the order of PG

• Journal of Microbiology and Biotechnology
• /
• 제15권4호
• /
• pp.855-858
• /
• 2005

The bioavailability of Ca is currently one of the most important topics in nutrition research and is correlated with gastrointestinal solubility. Thus, to increase the solubility of calcium, this study was undertaken to examine the effect of $\gamma$-PGA on intestinal Ca solubility. The calcium solubility increased when the amount of $\gamma$-PGA was increased, due to the inhibition of the formation of an insoluble Ca complex with phosphate. Therefore, when $\gamma$-PGA-500 (avg. MW 5,000 kDa) was added at 0.5 mg/ml, $75\%$ of the total Ca was soluble. The amount of soluble Ca uptake in the small intestine was investigated using Balb/c mice as an animal model system. The soluble Ca uptake in the mice orally administered with $\gamma$-PGA-500 (avg. MW 5,000 kDa) was significantly higher than that in the $\gamma$-PGA-l00 (avg. MW 1,000 kDa)-administered mice (P<0.05). Accordingly, these results strongly support the notion that the molecular size of $\gamma$-PGA is correlated with Ca solubility. The effects of other factors, such as casein phosphopeptide and vitamin D, on intestinal Ca absorption have also previously been investigated. Therefore, it is hoped that the present observations will help clarify the role of $\gamma$-PGA in Ca solubility and its industrial application as an additive.

• 한국세라믹학회지
• /
• 제15권1호
• /
• pp.16-20
• /
• 1978

The solubility of tobermorite was measured, and it was compaired with the resultswhich calculated by thermodynamic data. As the result, 1) The type of silisic acid species in liquid phase were the both type of $H_3SiO_4$-, $H_4SiO_4$. 2) The solubility product of tobermorite represented the maximum value at 18$0^{\circ}C$.

• 동의생리병리학회지
• /
• 제18권4호
• /
• pp.1098-1101
• /
• 2004

This study was carried out to investigate the solubility of the ingredients of the kidney stone in the solution of the traditional oriental medicines. Calcium hydroxide, apatite and uric acid were chosen as the ingredients of the kidney stone. Plantaginis Semen, Lysimachiae Herba, Saururi Herba seu Rhizoma, Imperatae Rhizoma, Allium tuberosum Rottler were studied as the oriental medicines for the kidney stone. Calcium hydroxide had showed the very good solubility in the solution of Imperatae Rhizoma, the apatite had showed the good solubility in the solutions of Saururi Herba seu Rhizoma and Allium tuberosum Rottler. Uric acid had showed the mild solubility in the solution of Lysimachiae Herba and Saururi Herba seu Rhizoma.

• 생약학회지
• /
• 제15권3호
• /
• pp.134-138
• /
• 1984

In this study the solubility of cholesterol was examined with ginseng saponin and chemical saponin used in the preparation of reaction mixture of 0.15M NaCl solution. It was shown that the solubility of cholesterol varied in the concentration of ginseng saponins and in the temperature and that the osmotic pressure and the surface tension was amenable to changes in the concentration of ginseng saponins and the incubation period of the reaction mixture. From the results, it was revealed that the solubility of cholesterol was dependent upon the incubated times and the concentration of ginseng saponins in 0.15mM NaCl solution and that ginseng saponins have the cholesterol solubilizing effect as evidenced in the physicochemical properties of mixed micelle formation and surface-activity.

• 한국응용약물학회:학술대회논문집
• /
• 한국응용약물학회 1996년도 춘계학술대회
• /
• pp.285-285
• /
• 1996

Cyclosporin A (CyA) is widely used in the inhibition of graft rejection in organ transplantation. However, the bioavailability of CyA after oral administration is very low due to its poor solubility and dispersability hi water. To improve the solubility of CyA, microemulsion systems were developed and its physicochemical characteristics were evaluated by phase studies, solubility and dispersability tests. Phase studies on the systems composed of ethyl oleate (EO), PPG-20 methyl glucose ether (GP-20), poloxamer 123 (PL) and water U) were carried out to make stable w/o emulsions. Besides, based on CyA solubility test in various compositions of surfactant systems, a reasonable surfactant composition (GP-20/PL=4/1) was selected to enhance its solubility.