• Membrane Journal
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• v.3 no.3
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• pp.136-139
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• 1993

It is well known that the membrane permeation in pervaporation is governed by both the chemical nature of the membrane material and the physical structure of the membrane and also the separation can be achieved by differences in either solubility, size or shape. The solubility of the penerrant in the polymeric membrane can be described qualitively by applying the Hildebrand relation [1] which relates the energy of mixing of the penerrant and the polymer material. Froehling et al. have tried to predict the swelling behavior of polymers for the systems of polyvinylchloride(PVC)-toluene-methanol, PVC-trichloroethylene-nitromethane and PVC-n-butylacetate-nitromethane[2]. The former two systems which do not show the donor/acceptor interactions upon mixing showed the successful results[2]. In addition to this technique, there are several other possible approaches to predict the swelling behaviors of polymers, such as the surface thermodynamic approach[3, 4], the comparison of the membrane polarity with the solvent polarity in terms of Dimroth's solvent polarity value[5].

• Korean Journal of Microbiology
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• v.19 no.3
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• pp.103-107
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• 1981

Increasing the concentration of the nonionic surfactants the solubility of methyl paraben was increased. This is called the solubilization phenomenon and caused inactivation of the preservatives used. The MICs(minimum inhibitory concentrations) on E. coli were increased at the same time. So the relation between the solubility and the mic could be expressed as $S-S_0=R^{\prime}/R^{\prime\prime}\;(M-M_0)$ and in this case $R^{\prime}/R^{\prime\prime}$ was about 2.

• Preventive Nutrition and Food Science
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• v.14 no.3
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• pp.220-225
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• 2009

In this study, the color value, water solubility, swelling power and sensory evaluation of Dioscorea batatas was examined with the addition of functional additives such as sugar alcohols and organic acids to investigate the browning inhibition and preference of these additives. Treatment with erythritol and citric acid were found to result in the highest hunter L-value, solubility and swelling power relative to the other functional additives. Therefore, erythritol and citric acid were selected as additives for Dioscorea batatas. The Dioscorea batatas containing the mixed additives (erythritol and citric acid) showed higher brightness, water solubility and swelling power than those containing only a single additive. In addition, the color and taste preference determined in the sensory evaluation had higher values when the mixed additives were used.

• Biomolecules & Therapeutics
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• v.1 no.1
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• pp.103-108
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• 1993

The synthesis and physicochemical properties of a novel cephalosporin, DWC-751 are described. DWC -751, (6R , 7R)-7-[ (Z)-2-(2-aminothiazol-4-yl)-2- methoxyiminoacetamido]-3-[(1-methylbenzotriazol-3-ium) methyl]-ceph-3-em-4-carboxylate monosulfate($IV_{\alpha}$) was conveniently obtained by the conversion of compound (IV) into the crystalline monosulfate. Adjusting pH 4.8-5.2 in aqeous solution of the crude crystalline, compound(IV) in the form of a crystalline pentahydrate was prepared with a high degree of purity. The influence of the various organic and inorganic acids on the solubility of compoud(IV) and its salts, was examined. Particularly, the solubility of DWC-751 was 92 mg/mι at pH 1.7 and 233 mg/mι at pH 3.0. DWC-751 showed a broad antimicrobial spectrum against gram-positive and negative bacteria.

• Journal of the Korean Society of Safety
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• v.10 no.1
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• pp.28-34
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• 1995

To improve fire proofing characteristics of protective coating using ternary soluble silicate from two component mixture, the method of reducing solubility, increasing intumescence and protection time have been studied. Intumescence and solubility of ternary silicate mixtures were dependent on many kinds of water release and the strength of cation cross-links between polysilicate particles. Especially the effect of additive, for example, corn starch was investigated. However the solubility of ternary mixture is decrease in order of Na$^{+}$ >K$^{+}$ >Li$^{+}$, and the magnitute of intumescence is increased $K^{+}$ >Na$^{+}$ >Li$^{+}$.}$ +/.

• Journal of Pharmaceutical Investigation
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• v.12 no.4
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• pp.132-144
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• 1982

The inclusion of ${\beta}-cyclodextrin$ $({\beta}-CyD)$ with prothionamide in aqueous phase was investigated by circular dichroism(CD), ultraviolet (UV) absorption, and solubility technique. The results suggested that a region of drug chromophore was located within the asymmetric center of ${\beta}-cyclodextrin$. Solubility and spectral changes were quantitatively treated to obtain stoichiometric ratio, which was found to be 1 : 1, and formation constants which were determined by solubility, CD, and UV method were 257, 367, and 389 $M^{-1}$, respectively. Also, the formation constant of the inclusion complex was determined by CD method at various pH. The result was that $K_c$ depended upon the pH of medium, and this fact also supported that thioamide moiety was accomodated in the cavity of ${\beta}-cyclodextrin$.

• Journal of Pharmaceutical Investigation
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• v.40 no.5
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• pp.277-283
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• 2010

CoQ with low melting temperature was exploited to improve its solubility by preparing its solid dispersions (SDs) with a meltable polymer, poloxamer 407 (P 407). P407 can be utilized for a relatively simple, quick, inexpensive, reproducible and potentially scalable manner in the low temperature melting method. CoQ 10 solubility and dissolution increased with increasing concentrations of P 407 in SDs. Comparison of the enhanced dissolution of CoQ 10 from different poloxamers suggested that the preparation of CoQ 10 SDs using P 407 as a meltable hydrophilic polymer carrier could be a promising approach to improve its dissolution.

• Biomolecules & Therapeutics
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• v.19 no.1
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• pp.109-117
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• 2011

In this work, we have investigated the effect of polyoxyethylene alkyl ester nonionic surfactants on percutaneous permeation enhancement of a model drug, ketoprofen. We also investigated the mechanism involved in the enhancement using impedance and solubility measurement. Three groups of nonionic surfactants with different ethylene oxide content were studied. The permeation results showed that all surfactants enhanced the percutaneous absorption, irrespective of the molecular weight. The permeation results from PEG-45 monostearate (PEGMS45) were rather unexpected. Impedance and solubility results indicate that the mechanism involved in the enhancement of permeation by PEG-10 monooleate (PEGMO10) and PEGMS45 is rather different. The results from PEGMS45 suggest that it could be a potential candidate as a skin penetration enhancer with high molecular weight, which may poses less skin irritation and systemic side effect than the smaller surfactant molecules. Overall, this work provided some useful information on percutaneous transport enhancement and the mechanistic insights involved in skin permeation for these nonionic surfactants.

• Journal of Mechanical Science and Technology
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• v.19 no.5
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• pp.1216-1225
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• 2005

$CO_{2}$ ocean sequestration is one of the promising options to reduce $CO_{2}$ concentration in the atmosphere because the ocean has vast capacity for $CO_{2}$ absorption. Therefore, in the present investigation, calculations for solubility and dissolution behavior of liquid $CO_{2}$ droplets released at 1000 m and 1500 m deep in the ocean from a moving ship and a fixed pipeline have been carried out in order to estimate the $CO_{2}$ dissolution characteristics in the ocean. The results show liquid $CO_{2}$ becomes bubble at around 500 m in depth, and the solubility of seawater is about $5{\%}$ less than of pure water. Also, it is shown that the injection of liquid from a moving ship is a more effective method for dissolution than from a fixed pipeline, and the presence of hydrate on liquid $CO_{2}$ acts as a resistant layer in dissolving liquid $CO_{2}$.

• Biomolecules & Therapeutics
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• v.8 no.4
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• pp.332-337
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• 2000

Physicochemical properties of aspalatone (acetylsalicylic acid maltol ester, AM), which has been recently found to have an antithrombotic effect, were studied in terms of solubility, dissolution, partition coefficient (Pc) and stability. The solubility of AM at 37$^{\circ}C$ was about 1.2 mg/ml and the P$_{c}$ value for n-octanol/water and chloroform/water was 11.4 and 382.6, respectively. Dissolution rates of AM at pH 1.2 and 6.8 were more than 80% within 30 min. The degradation of AM followed apparent first-order kinetics, and was dependent on temperature, pH and ionic strength. From the pH-rate profile, the optimal pH was found to be at around 4.0. Half-lives at pH 1.2 and 6.8 were 33.5 and 44.4 hr, respectively. The degradation rate of AM at pH 1.2 was somewhat faster than that of aspirin, but at pH 7.0, the degradation rate of AM was slower than that of aspirin.n.