• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• v.3 no.2
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• pp.137-142
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• 1999

One of the most important parameters required to model the absorption of CO2 into aqueous alkanolamine solutions is physical solubility. However, since CO2 reacts in amine solutions, its physical solubility cannot be measured directly. As a result, a nonreacting gas which is similar to CO2 has to be used such as N2O. The solubility of nitrous oxide (N2O) in aqueous solutions of 0wt%-50wt% MDEA, 0wt%-30wt% DEA, and 50wt % total amine with DEA/MDEA molar ratios of 0.05, 0.25, 0.5 and 0.67 was measured using a modified Zipperclave reactor over a temperature range of 293-353 K with near atmospheric partial pressures of N2O. the solubility data from this work were K with near atmospheric partial pressures of N2O. The solubility data from this work were found to be in good agreement with previously reported data where available.

• Journal of Powder Materials
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• v.30 no.1
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• pp.47-52
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• 2023

The purpose of this study is to develop and evaluate amorphous spray-dried microparticles (SDM) containing levosulpiride to increase its solubility. SDM are prepared via solvent evaporation using polyvinylpyrrolidone (PVP) as the water-soluble polymer and Cremophor RH40 as the surfactant. The SDM is prepared by varying the amounts of PVP and Cremophor RH40, and its physicochemical properties, solubility, and dissolution are confirmed. All levosulpiride-loaded SDMs converted the crystalline drug into an amorphous form, significantly improving drug solubility and dissolution compared with the drug alone. SDM consisting of drug/PVP/Cremophor RH40 in a weight ratio of 5:10:3, with increased solubility (720 ± 36 vs. 1822 ± 51 ㎍/mL) and dissolution rate (10.3 ± 2.2 vs. 92.6 ± 6.0%) compared with drug alone, shows potential as a commercial drug for improved oral bioavailability of levosulpiride.

• Journal of Pharmaceutical Investigation
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• v.33 no.1
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• pp.57-60
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• 2003

To enhance the solubility of poorly water-soluble ibuprofen with poloxamer and menthol, the effects of menthol and poloxamer 188 on the aqueous solubility of ibuprofen were investigated. In the absence and presence of additives such as ethanol and poloxamer 188, the solubility of ibuprofen increased until the ratio of menthol to ibuprofen increased from 0:10 to 4:6 followed by an abrupt decrease in solubility above the ratio of 4:6, indicating that 4 parts of ibuprofen formed eutetic mixture with 6 parts of menthol. In the presence of poloxamer, the solutions with the same ratio showed abrupt increase in the solubility of ibuprofen. Furthermore, in the presence of poloxamer, the solution with ratio of 4:6 showed more than 2.5- and 6-fold increase in the solubility of ibuprofen compared with that without additives and that without menthol, respectively. The solution with menthol/ibuprofen ratio of 1:9 and higher than 15% poloxamer 188 showed the maximum solubility of ibuprofen, 1.2 mg/ml. Thus, menthol gave the greatly enhanced solubility of ibuprofen with poloxamer 188.

• The Journal of Korean Academy of Prosthodontics
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• v.9 no.1
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• pp.41-45
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• 1969

A major disadvantage of Dental cements is their solubility. So it is very important to measure the exact amount of solubility to select clinically suitable materials. The most common laboratory test for solubility is the measurement of disintegration in distilled water, as outlined in A.D.A. Specifications 8 and 9, In addition to the possible factors influencing the solubility, the experiments were all conducted in compliance with A.D.A. Specifications. The solubility of 2 Zinc Phosphate cements and 1 Silicate cement in time of dissolution, concentration of solute in dissolving medium, and type of dissolving medium were investigated. The following results were obtained. 1. Generally the materials were more soluble in organic acids than in distilled water. 2. The dissolution cements tends be minimized by tests utilizing prolonged storage in the same media. 3. In Acetic acid solution, Zinc Phosphate cements were more soluble than Silicate cement, and in Citric acid solution both were markedly more soluble. 4. Solubility was increased by continually presenting fresh liquid, unsaturated with solute, to the cement-water interface.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.8
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• pp.1159-1165
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• 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 Nutrition and Health
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• v.29 no.8
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• pp.861-866
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• 1996

Tannins in plant foods and beverages may produce antinutritional or toxic effects although some proteins with high affinity for tannins seem to function as defense mechanism to tannin toxicity. Our objectives were to investigate of tea tannins, iron and protein and to evaluate the role of proteins in tannin effects on iron solubility. Iron solubility in vitro was measured using tea with and without proteins. Mixtures of tea, protein in varying concentrations(either gelatin or bovine serum albumin), and iron(eithe 10 or 50ug/mL) were prepared. Controls contained water in place of tea. Iron bioavailability was assessed by measuring iron solubility in the simulated gastric condition with pepsin digestion. Bound iron was removed by centrifugation and soluble in tea alone. When iron concentratin was 10ug/mL, addition of small amounts of protein to tea dramatically reduced iron solubility, but solubility of iron increased in the tea mixturea as the concentration of protein was increased. The percnetage of iron that precipitated was much greater at 10ug Fe/mL than the values at 50ug Fe/mL suggesting that the iron binding sites on the tea-protein complex was saturated. These results suggest that interactions of iron with tea tannins are influenced by the concentratins of protein and iron.

• Food Science and Preservation
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• v.12 no.5
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• pp.501-506
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• 2005

This study was conducted to investigate the effect of organic acids on solubility of calcium. As a results, acetic and lactic acid showed the most excellent solubility of calcium. Calcium solubility was increased at initial total acid (4%) in citric acid but calcium was insoluble in tartaric acid. After solving, pH and residuals were decreased where as total acidity and calcium content were increased as increment of initial acidity of acetic and lactic acid. Calcium content in seaweed calcium and calcium carbonate were higher than that of nano calcium. Solubility of calcium was more conspicuous at lactic acid than acetic acid.

• Mass Spectrometry Letters
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• v.7 no.3
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• pp.79-83
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• 2016

We prepared solid dispersion formulations of quercetin to enhance its solubility and dissolution rate. Various quercetin-loaded solid dispersion were tested with quercetin, poloxamer 407, and carrier such as hydroxypropyl methyl cellulose (HPMC), polyethylene glycol 8000 (PEG 8000), and polyvinylpyrrolidone K40 (PVP K40) using solvent evaporation and freeze drying methods in terms of both the aqueous solubility and the dissolution rates of quercetin. The solubility of quercetin as its solid dispersion formulations was markedly improved compared with that of quercetin powder. Especially, highest solubility of quercetin was observed when HPMC was used as a carrier. The cumulative dissolution of quercetin within 360 min from solid dispersion composed of quercetin, poloxamer 407, and HPMC was 8.8-fold higher than the dissolution of pure quercetin. The results of powder X-ray diffraction (XRD) and scanning electron microscope (SEM) indicated that quercetin transformed from a crystalline to an amorphous form through the solid dispersion formulation process. These results suggest that the solid dispersion formulation of quercetin with poloxamer 407 and HPMC could be a promising option for enhancing the solubility and dissolution rate of quercetin.

• Journal of Pharmaceutical Investigation
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• v.27 no.3
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• pp.199-205
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• 1997

In order to formulate biphenyl dimethyl dicarboxylate(DDB) aqueous solutions, the effects of various solubilizing agents such as cosolvents(PG, PEG 400, glycerin, ethanol), surfactants,$(poloxamer\;407,\;Cremophor^{\circledR}\; RH40,\;Solutol^{\circledR},\;Tween\;80,\;sodium\;lauryl\;sulfate)$, complexation agent$(CELDEX^{\circledR}\;CH-20)$ and others(urea, niacinamide, propylene carbonate, HPMC) on the solubility of DDB in water were evaluated. The solubility of DDB in water was about $0.21\;{\mu}g/ml\;at\;20^{\circ}C$, while its solubility in PEG 400 was 5,000 times higher than that in water. 60% PEG 400 aqueous solution was selected as an optimum solvent system, and surfactants or other solubilizing agents were added to prevent DDB from recrystalization. The addition of surfactants in water increased the solubility of DDB from 15- to 34-fold, however, $CELDEX^{\circledR}\;CH-20$ and other agents studied showed negligible effects on the solubility of DDB in water. The 60% PEG 400 aqueous solution containing 5% $Cremophor^{\circledR}$　RH40 was appeared as the formula of choice. It showed acceptable physical stability after stored for 7 days at $4^{\circ}C$.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.19 no.1
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• pp.113-121
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• 2021

A safety assessment of radioactive waste repositories is a mandatory requirement process because there are possible radiological hazards owing to radionuclide migration from radioactive waste to the biosphere. For a reliable safety assessment, it is important to establish a parameter database that reflects the site-specific characteristics of the disposal facility and repository site. From this perspective, solubility, a major geochemical parameter, has been chosen as an important parameter for modeling the migration behavior of radionuclides. The solubilities were derived for Am, Ni, Tc, and U, which were major radionuclides in this study, and on-site groundwater data reflecting the operational conditions of the Gyeongju low and intermediate level radioactive waste (LILW) repository were applied to reflect the site-specific characteristics. The radiation dose was derived by applying the solubility and radionuclide inventory data to the RESRAD-OFFSITE code, and sensitivity analysis of the dose according to the solubility variation was performed. As a result, owing to the low amount of radionuclide inventory, the dose variation was insignificant. The derived solubility can be used as the main input data for the safety assessment of the Gyeongju LILW repository in the future.