• Restorative Dentistry and Endodontics
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• v.10 no.1
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• pp.17-30
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• 1984

This study was done to evaluate the hardness, water sorption and solubility values of twelve well known composite resins, and to compare each other. For the hardness test, the specimens were made in cylinder form with 4mm in diameter and 2mm in thickness as a modification of the American Society for Testing and New Materials, 1966, and for water sorption and solubility tests, the specimens were prepared in same shape of 20mm in diameter and 0.5mm in thickness as a modification of the ADA Specification No. 12. The results were obtained as follow: 1. The hardness range were from 17.9 to 87.5 respectively. As time passed by, the noticable change was evident in early 12 hours. 2. Of the water sorption. the range was from 0.38 to 0.93. The significant change was appeared within 12 hours and on 3 day by 1 week except four brands. 3. Of the water solubility, the range was 0.06 to 0.16. The highest value was found within early 24 hours. 4. Generally, four brands could be chosen as preferable products of hardness. water sorption and solubility tests according to the ADA Specification No. 12.

• Food Science and Biotechnology
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• v.17 no.4
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• pp.833-838
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• 2008

Size effects of rice product powders on physical properties including suspension stability were investigated in this study. Endosperm, bran, and husk powders of rice with different size particles were prepared using the pin crusher or the ultrafine air mill. The physical properties of the powders were examined using particle size analysis, scanning electron microscopy, and spectrophotometry. The peak of the volume-weighted particle distribution of ultrafine endosperm particles was at $5.4\;{\mu}m$ whereas those of the bran and the husk appeared at 65 and $35\;{\mu}m$, respectively. Ultrafine particles of the endosperm and the husks dispersed better than larger-sized particles. As time elapsed, the dispersibility decreased, but the ultrafine particles were precipitated at the slowest rate. Our results suggest that ultrafine particles, including future nanosized particles, provide improved solubility and dispersibility resulting in better stability in the food colloidal suspension.

• The Journal of Korean Academy of Prosthodontics
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• v.43 no.1
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• pp.1-14
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• 2005

Statement of problem. Among the physical properties of adhesion luting cement, the aspect that requires the most important factor is the degree of solubility and water sorption. Dissolution or an inadequate due to excessive water sorption inside the oral cavity compromises the while concurrently increasing the susceptibility to secondary dental caries. Susceptibility to dissolution and difficulty of removing remnant cement from the gingival sulcus have hindered the use of dental resin cement in the clinical practice, but the improved characteristics of newer generation resin cements have interest in and enabled resin cements to be widely used in adhesion of fixed prosthesis, such as laminate veneers and all-ceramic crowns. Purpose. The purpose of this study is to compare and analyze the degrees of solubility and water sorption of a variety of resin cements widely used for clinical purposes with different curing methods. Material and methods. Self-curing resin cements, $Avanto^{(R)}$, $C&B^{TM}$ CEMENT and Superbond C&B cements comprised group 1, 2 and 3. The dual-curing resin cements $Panavian^{TM}$ F, $Calibra^{(R)}$ and $Variolink^{(R)}$ II were divided into groups 4, 5, and 6, respectively. The investigation was carried out using disc-shaped specimens as specified by ANSI/ADA Specification No. 27. The degree of water sorption, water solubility and lactic acid solubility of each test group was analyzed statistically leading to the following conclusion. Results. The degree of water sorption was shown to increase in the following order : group 6, 5, 4, 2, 1 and 3. There were significant differences between the water sorption of each group. Results of the degree of water solubility were shown to increase in the following order : group 6, 5, 4, 2, 1 and 3. Statistically significant differences were found between each group, with the exception of groups 1 and 3. Finally, the degree of lactic acid solubility was found to increase in the following order : group 6,5,4,2,3 and 1. Significant differences were found between each group. In general dual-curing resin cements displayed substantially lower values than self-curing resin cements with regard to water sorption, water solubility, and lactic acid solubility. Conclusions. From the results of this study, dual-curing resin cements show a significantly lower degree of water sorption and solubility than their self-curing counterparts. Clinically, when selecting resin cements, the product with a lower degree of water sorption and solubility are preferred. The results of this study indicate that the use-of dual-curing resin cements is preferable to self-curing cements.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.11
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• pp.4643-4648
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• 2010

In this study, $CO_2$ absorption properties at high pressure condition that can apply pre-combustion $CO_2$ capture were investigated for physical sorbent such as PEG, DMSO, and Sulfone. The $CO_2$ Solubility, regeneration, and initial absorption rate with temperature and pressure were measured using batch type stirred cell contactor. The PEG showed the highest $CO_2$ solubility and initial absorption rate. It can be found that all the physical sorbents used in this experiments were almost completely regenerated at various temperature and pressure.

• YAKHAK HOEJI
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• v.50 no.1
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• pp.1-7
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• 2006

The purpose of the present study was to formulate the aqueous solution of 1-cyclopent-3-enylmethyl-6(3,5-dimethyl-benzoyl)-5-ethyl-1H-pyrimidine-2,4-dione (CPD), a novel antivirus compound containing pirimidine structure. For this purpose, the effects of various solubilization agents such as cosolvents [ethanol, propylene glycol (PG), polyethylene glycol 300 (PEG 300), polyethylene glycol 400 (PEG 400), glycerin], surfactants (Tween 80, Cremophor$^{(R)}$ RH40, Cremophor$^{(R)}$ EL, Poloxamer 407, Poloxamer 188) and a complexation agent [hydroxypropyl-${\beta}$-cyclodextrin (HPBCD)] , on the solubility of CPD in aqueous solution were evaluated. The solubility of CPD in water was under $1\;{\mu}g/ml$ at $20^{\circ}C$. Cosolvents such as ethanol, PG, PEG 300, PEG 400 and glycerin did not enhance the solubility of CPD at the $0{\sim}40\%$ concentration range. The solubility of CPD was significantly elevated by the addition of cosolvents over the $80\%$ concentration range. On the other hand, tween 80, Cremophor$^{(R)}$ L, Cremophor$^{(R)}$ RH40, and HPBCD showed enhanced effects on the solubility of CPD. The enhanced effects of Poloxamer 407 or Poloxamer 188 on the CPD solubility were less pronounced compared with tween 80, Cremophor$^{(R)}$ L or Cremophor$^{(R)}$ RH40. As a results, tween 80 aqueous solution was selected as an optimum solvent system. The aqueous solutions containing $20\%$ tween 80 were formulated as a dosing solution containing CPD for its intraperitoneal and intrahypodermic administration, respectively, The formular showed physical stability after stored for 7 days at $4^{\circ}C$.

• Journal of Pharmaceutical Investigation
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• v.34 no.5
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• pp.385-391
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• 2004

The purpose of the present study was to formulate the aqueous solution of $20-O-{\beta}-D-glucopyranosyl-20(S)-protopanaxadiol\;(IH-901)$, an intestinal bacterial metabolic derivative from Ginseng protopanaxadiol saponin. For this purpose, the effects of various solubilization agents such as cosolvents [ethanol, propylene glycol (PG), polyethylene glycol 300 (PEG 300), polyethylene glycol 400 (PEG 400), glycerin], surfactants $(Tween\;80,\;Cremophor^{\circledR}\;RH40,\;Cremophor^{\circledR}\;EL,\;Poloxamer\;407,\;Poloxamer\;188)$ and a complexation agent $[hydroxypropyl-{\beta}-cyclodextrin\;(HPBCD)]$, on the solubility of IH-90l in aqueous solution were evaluated. The solubility of IH-901 in water was under $1\;{\mu}g/ml\;at\;20^{\circ}C$. Cosolvents such as ethanol, PG, PEG 300, PEG 400 and glycerin did not enhance the solubility of IH-901 at the 0 - 40% concentration range. The solubility of IH-901 was significantly elevated by the addition of cosolvents over the 80% concentration range. On the other hand, tween 80, $Cremophor^{\circledR}\;EL,\;Cremophor^{\circledR}\;RH40$ and HPBCD showed enhanced effects on the solubility of IH-901. The enhanced effects of Poloxamer 407 or Poloxamer 188 on the IH-901 solubility were less pronounced compared with $Cremophor^{\circledR}\;EL\;or\;Cremophor^{\circledR}\;RH40$. As a results, $Cremophor^{\circledR}$ aqueous solution was selected as an optimum solvent system. The aqueous solutions containing 10% $Cremophor^{\circledR}\;EL$ and 7% $Cremophor^{\circledR}\;RH40$ were formulated as dosing solutions containing 5.0 mg/ml of IH-901 for its intravenous and oral administration, respectively. The formular showed physical stability after stored for 7 days at $4^{\circ}C$.

• Journal of Environmental Science International
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• v.7 no.6
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• pp.753-759
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• 1998

In physical and reactive extraction of acrylic acid using various solvents the equilibrium characteristics of extraction were investigated. The degree of extraction in reactive extraction with Tri-n-octylamine(TOA) was 1.5~3 times than that in physical extraction. Distribution ratio was constant in methyl isobutyl ketone(MIBK) and n-butylacetate(n-BAc) but was increased with increasing the concentration of acrylic acid in benzene and chloroform. It can be explained by formation of dimers. Maximum extraction leadings of acrylic acid were three in benzene and were two in MIBK, chloroform and n-BAc, and it was found that acrylic acid was extracted as the form of $A_3$R In benzene and $A_2R$ in MIBK, chloroform and n-BAc. In effect of solvent, the degree of extraction was increased as he difference of solubility parameter of solvent and solute was decreased, and as dielectric constant of solvent was increased.

• Elastomers and Composites
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• v.25 no.3
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• pp.195-202
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• 1990

Rubber-modified polyurethane resin which was prepolymer type terminated with NCO, was synthesized by reacting isocyanate groups[NCO] and hydroxyl groups[OH]. Polybutadiene rubbers which had OH groups in the side of rubber chains, were charged at ratio $0%{\sim}40%$ of solid component in reactants. For products, physical properties were investigated experimentally. The results abtained in experiment were as follows. 1. Liquid resin and dried film was good solubility and clearity at less than 25%, 20% of rubber without being related to sort. 2. G-1000 showed better properties than R-45HT in solubility, dring time and adhesive strength. 3. Dring time and adhesive strength were considerably influenced by molecular weigh and structure of rubber. 4. In using 25% of mixed rubber(G-1000/R-45HT=50/50), It represented best properties in dring time(10 minute) and adhesive strength($23Kg/cm^2$).

• YAKHAK HOEJI
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• v.25 no.4
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• pp.187-192
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• 1981

In order to increase the dissolution rate on the mixture of sulfamethoxazole and trimethoprim (SMX-TMP), their coprecipitates with polyvinylpyrrolidone (PVP) were studied. Coprecipitates prepared with various ratios of SMX and TMP were examined such as hygroscopicity, apparent solubility, apparent partition coefficient and the dissolution behavior of SMX-TMP's coprecipitates and their physical mixtures. The hygroscopicity of coprecipitates were less than that of physical mixtures. The apparent solubility and dissolution rate of SMX-TMP's coprecipitates were found to be greatly increased. The dissolution rates of SMX and TMP in the coprecipitates were decreased when the ratio of two ingredients to PVP was smaller, and the dissolution rate of SMX was increased when the ratio of SMX to TMP was larger.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.215.3-216
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• 2003

Eupatilin is a major active component of Stillen\ulcorner(Artemisia Herba Extract) having a potent antigastritic effect. We investigated the physical properties of eupatilin using high performance liquid chromatography. Solubility, stability & partition coefficient of eupatilin were investigated. pH-stability of eupatilin was examined over the broad range through pH1-9 at 37$^{\circ}C$ & it has good stability above the broad range pH. The solubility of eupatilin was extremely low but the value of logP was more than 2. Also, a high performance liquid chromatographic method was developed for the determination of eupatilin in rat plasma. (omitted)