• Journal of the Korean Recycled Construction Resources Institute
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• v.9 no.3
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• pp.397-404
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• 2021

In this study, it was reviewed that the effect of solid capsules on the quality of surface repair materials and the healing properties of long-term aging, as part of a study to utilize self-healing surface repair materials using solid capsules as repair materials. As a result of evaluation of the rheological properties of self-healing surface repair materials according to the mixing of solid capsules, plastic viscosity, yield stress, and table flow tended to decrease. In the case of compressive strength, 1MPa per 1% of the solid capsule decreased proportionally. As a result of evaluating the long-term healing properties, when 10% of solid capsules were mixed, a healing rate of 90% was shown at 28 days of healing, because the solid capsule was preserved even after 91 days of age had elapsed. after 91 days of healing, even in the case of 5% of solid capsules, a healing rate of 90% was shown.

• Journal of the Korean Recycled Construction Resources Institute
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• v.8 no.1
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• pp.120-128
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• 2020

In this study, solid capsules using crystal growth-type inorganic materials that can be directly mixed with mortar were prepared. Thus, three levels of solid capsules were prepared. The prepared solid capsule was mixed with 3% of the cement mass, was evaluated quality and crack healing properties of the mortar. As a test results of the table flow and air content of the mortar mixed with the solid capsules showed that mix of the solid capsules was no effect on the table flow and air volume. As a test result of the crack healing properties of the mortar mixed with the solid capsule according to water flow test and crack closing test, the initial flow rate was decreased, it was confirmed that the reaction product occurred over time and the cracks were healed.

• Journal of the Korea institute for structural maintenance and inspection
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• v.25 no.2
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• pp.16-22
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• 2021

In this paper, a solid capsule was prepared using a crystal growth type inorganic material capable of hydration reaction. The solid capsules were mixed at 3, 5, and 10% according to the composition ratio of 8:2, 7:3, 6:4 based on the cement mass, and the self-healing mortar was mixed, Durable healing properties were evaluated through the water permeability test. As a result of the water level permeability test, the effect of optimally improving the natural healing performance was shown by mixing the solid capsules prepared in a composition ratio of 7:3 of the solid capsules. In the case of a crack width of 0.3mm or less, it is estimated that more than 90% of the self-healing performance can be secured. As a result, it was judged that the self-healing performance of the solid capsule had an effect on the durable healing properties through the water permeability test, It is judged that there is a tendency to improve self-healing performance according to the mixing of solid capsules.

• Journal of the Korean Recycled Construction Resources Institute
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• v.8 no.4
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• pp.475-482
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• 2020

In this study, three levels of solid capsules were prepared according to the composition ratio of core materials for the crystal growth type self-healing solid capsule, and a cement mortar was prepared with the crystal growth type self-healing solid capsule. The prepared solid capsule was mixed with 3% of the cement mass to evaluate the healing properties according to the crack induction age of the cement mortar. As a result of test, the crack healing properties according to the crack induction age of cement mortar mixed of solid capsules, it was confirmed that the self-healing performance of the cement mortar with the solid capsules was increased self-healing performance of 7 days than 28 days. This is because the unhydrated binder remains.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1997.04a
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• pp.118-118
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• 1997

Solid dispersions were used to increase the dissolution rate of biphenyl dimethyl dicarboxylate (DDB) in water, with the ultimate goal of optimizing its bioavailability when incoporated into pharmaceuticals. Carriers used were Kollidon 30, Kollidon VA 64, 2-hydroxypropyl-${\beta}$-cyclodextrin (HPCD), sodium salicylate or sodium benzoate. DDB solid dispersions were prepared at drug to carrier proportions ranging from 1 : 5 to 1 : 20 (w/w) by solvent evaporation method. DDB tablets (7.5 mg) were prepared by compressing the powder mixture composed of solid dispersions, lactose, corn starch, crospovidone and magnesium stearate using a single-punch press. DDB capsules (7.5 mg) were prepared by filing the mixture into empty hard gelatin capsules (size #1). Dissolution studies of DDB from powdered solid dispersions, tablets and capsules were performed in 900 $m\ell$ of water at 100 rpm and 37$^{\circ}C$ by the paddle method. The dissolved amount was assayed by HPLC and expressed as the mean(%)of three determinations.

• Journal of the Korean Recycled Construction Resources Institute
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• v.8 no.4
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• pp.581-589
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• 2020

In this paper, a solid capsule was prepared using a crystal growth type inorganic material capable of hydration reaction, the quality and mechanical healing properties of self-healing mortar with solid capsules were evaluated. Solid capsules were mixed 5% by mass of cement. Reloading test results of compressive load, it was found to improve about 20% on average for the natural healing effect of Plain, in the case of the elastic range, the healing rate was about 79% at the 7 days of healing age and 98% at the 28 days of healing age. Reload test results of flexural load, in the case of the elastic range, the healing rate was about 79% at the 7 days of healing age and 98% at the 28 days of healing age. Through these results, it is judged that the healing performance of solid capsules has also an effect on mechanical healing properties such as strength in addition to the durability properties obtained by the permeability test. Since the strength tends to decrease as the solid capsules are mixed, it is considered necessary to compensate.

• Journal of the Korean Recycled Construction Resources Institute
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• v.10 no.3
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• pp.335-342
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• 2022

In this study, self-healing hybrid capsules were prepared by mixing self-healing solid capsules and self-healing microcapsules using inorganic materials as core materials. Self-healing hybrid capsules were mixed with 3 % according to the composition ratio of 3:7, 5:5, and 7:3 based on the mass of the cement to prepare a self-healing cement composite material. The healing properties of crack self-healing hybrid capsules were evaluated through hydrostatic water permeability test and surface crack monitoring. It was found that the self-healing hybrid capsules prepared by mixing the composition ratio of the self-healing solid capsules and the self-healing microcapsules at 7:3 has a great effect on improving the crack self-healing performance.

• Journal of Pharmaceutical Investigation
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• v.29 no.3
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• pp.227-234
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• 1999

Solid dispersions were prepared to increase the dissolution rate of biphenyl dimethyl dicarboxylate (DDB) using water-soluble carriers such as povidone, copolyvidone, $2-hydroxypropyl-{\beta}-cyclodextrin (HPCD)$, sodium salicylate or sodium benzoate by solvent evaporation method. Solid dispersions were characterized by infrared spectrometry, differential scanning calorimetry (DSC) and powder X-ray diffractometry, dissolution and permeation studies. DDB tablets (7.5 mg) were prepared by compressing the powder mixtures composed of solid dispersions, lactose, com starch, crospovidone and magnesium stearate using a single-punch press. DDB capsules (7.5 mg) were also prepared by filling the mixtures in empty hard gelatin capsules (size No.1). From the DSC and powder x-ray diffractometric studies, it was found that DDB was amorphous in the HPCD or copolyvidone solid dispersions. Dissolution rates after 10 min of DDB alone and solid dispersions (1 : 10) in sodium benzoate, sodium salicylate and copolyvidone were 11.8, 23.5, 22.8 and 82.5%, respectively. Dissolution rates of DDB after 30 min from 1 : 10 and 1 : 20 copolyvidone solid dispersions were 80.5 and 95.0%, respectively. For the DDB tablets prepared using solid dispersions (1 : 20), the initial dissolution rate was dependent on carrier material, and was ranked in order, $Kollidon\;30\;{\ll}$ copolyvidone < HPCD. For the HPCD solid dispersion tablets, dissolution rate reached 97.4% after 15 min, but thereafter slowly decreased to 80.7% after 2 hr due to the precipitation of DDB. However, in the case of copolyvidone solid dispersion tablets, dissolution increased linearly and reached 93.4% after 2 hr. Reducing the volume of test medium from 900 to 300 ml markedly decreased the dissolution rate of the tablets containing 1 : 20 HPCD solid dispersions and 1 : 10 copolyvidone solid dispersion. For 1 : 20 copolyvidone solid dispersion tablets, there was no significant change in dissolution rate up to 1 hr with different volumes of test medium. Preparation of the copolyvidone solid dispersion (1 : 20) in capsules markedly delayed the dissolution (31.2 % after 2hr) due to the limited diffusion within capsules. The permeation rate $(13.4\;g/cm^2\;after\;8\;hr)$ of DDB through rabbit duodenal mucosa from copolyvidone solid dispersion (1 : 10) was markedly enhanced, when compared with drug alone or physical mixtures. From overall findings, DDB formulations containing copolyvidone solid dispersions (1 : 20) could be used to remarkably improve the dissolution rate in dosage form of powders and tablets.

• Journal of the Korea institute for structural maintenance and inspection
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• v.24 no.1
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• pp.59-66
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• 2020

In this study, self - healing solid capsules of crystal growth type which can be mixed directly with repair mortar were prepared, and the quality and crack healing performance of repair mortar with self - healing solid capsules were evaluated. The table flow and the air flow rate of the repair mortar material mixed with self-healing solid capsules were found to have no significant influence on table flow and air volume regardless of mixing ratio. Compressive strength tended to decrease with increasing capsule mixing ratio. As a result of evaluation of crack healing properties according to constant water head permeability test, initial water permeability decreased, and reaction products were generated over time and cracks were healed.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.412.1-412.1
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• 2002

Purpose. To prepare PVP-based solid dispersions containing lovastatin (LOS) and solubilizers (sodium lauryl sulfate. Tween80. oleic acid) to enhance dissolution of practically insoluble LOS. Methods. Solid dispersions containing LOS were prepared by dissolving two different organic solvent systems (acetone/ethanol or acetonitrile/ethanol). Results. The stickiness and flowability of solid dispersion powders were dependent on the composition and ratio of the solubilizers. (omitted)