• Polymer(Korea)
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• v.26 no.3
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• pp.326-334
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• 2002

The purpose of this work was the producing of a biodegradable poly($\varepsilon$-caprolactone) (PCL) microcapsule and the analyzing of form and features for the manufacturing conditions which could be observed in a prospective drug delivery systems (DDS) through drug release. The effects of different stirring rates, stirring times and concentrations of emulsifier for the diameter and form of the microcapsules were observed using image analyzer (IA) and scanning electron microscopy (SEM). As a result, the microcapsules were made in wrinkle and spherical forms with a mean particle size of 40~300$\pm$20 $mu extrm{m}$. PCL microcapsules containing drugs were confirmed using FT-IR spectra. The role of interfacial adhesion between PCL and drug was determined by contact angle measurements. The drug release test of PCL microcapsules was characterized by UV/vis. spectra. It was found that the drug release rate of the microcapsules prepared with high concentration emulsifier was significantly fast.

• Journal of Pharmaceutical Investigation
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• v.25 no.1
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• pp.31-36
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• 1995

Solid dispersions and inclusion complex were prepared for the enhancement of solubility and dissolution rate of poorly water-soluble ibuprofen(IPF) as a model drug. Polyethylene glycol 4000(PEG4000) and polyvinylpyrrolidone(PVP) were used for the preparation of solid dispersion. $2-Hydroxypropyl-{\beta}-cyclodextrin(2-HP{\beta}CD)$ was also used for the preparation of inclusion complex. The solubility of IPF increased as the concentration of PEG4000, PVP and $2-HP{\beta}CD$ increased. Solubilization capacity of $2-HP{\beta}CD$ was increased about 10 times when compared to PEG 4000 and PVP. The dissolution rate of drug from solid dispersions and inclusion complex in the simulated gastric fluid was enhanced when compared to pure IPF and commercial $BR4^{\circledR}$ tablet as a result of improvement of solubility. In case of solid dispersions, dissolution rate of drug was proportional to polymer concentration in the formulation. The marked enhancement of dissolution rate of drug by inclusion complexation with $2-HP{\beta}CD$ was noted. However, dissolution rate of drug from solid dispersions and inclusion complex in the simulated intestinal fluid was not significant because IPF was readily soluble in that condition. From these findings, water-soluble polymers and cyclodextrin were useful to improve solubility and dissolution rate of poorly water-soluble drugs. However, easiness and reliability of preparation method, scale-up and cost of raw materials must be considered for the practical application of solid dispersion and inclusion complex in pharmaceutical industry.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.19
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• pp.59-68
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• 1975

A soybean variety KWANG KYO was planted on the hilly land and fertile soil, and concentrated superphosphate and fused phosphate were applied on calcium hydroxide treated soil at level of 2.5%, 5% and 7.5% of phosphate absorbtion coefficient of soil. Application of phosphate fertilizer and lime caused higher grain yield in hilly land soil than fertile soil. The effect of fused phosphate on soybean yield was superior to concentrated superphosphate, and the effect of lime on fused phosphate availability was not significant. When the two phosphate sources were compared at equal $P_2O_5$ basis, fused phosphate required higher amount than concentrated super-phosphate. Negative correlation was obtained between potassium content and Ca + Mg in soybean leaf and in soil respectively.

• Journal of the Korean Wood Science and Technology
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• v.27 no.2
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• pp.46-52
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• 1999

Alkaline sulfite-anthraquinone(AQ) cooking was examined for their effectiveness in delignification of pine (Pinus densiflora S. et Z.) bark. Better delignification was achieved with alkaline sulfite liquor compared to monosulfite liquor, but the degree of delignification was less than 90% indicating need for improvement in cooking method, Remarkable increase in the rate of cooking and delignification was obtained by the simple addition of AQ to the alkaline sulfite cooking, Selectivity of delignification was also improved by the addition of AQ, Consequently, 90% of delignification was achieved with the addition of 0.2% AQ to the alkaline sulfite cooking. The selectivity of delignification was slightly affected by cooking temperature and NaOH concentration during alkaline sulfite-AQ cooking of the bark. The selectivity of delignification was highly affected by the concentration of $Na_2SO_3$, and the optimum concentration of $Na_2SO_3$ for the high delignification was 30% as $Na_2O$.

• Korean Journal of Food Science and Technology
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• v.35 no.3
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• pp.405-409
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• 2003

This study was conducted to evaluate quality characteristics of noodles containing barley flour and ${\beta}$-glucan enriched fraction. Compared to 100% wheat flour, composite flours containing barley flour and ${\beta}$-glucan enriched fraction decreased initial pasting temperature and increased maximum peak viscosity. The noodles containing ${\beta}$-glucan enriched fraction exhibited somewhat darker color and lower values in cooked weight, volume, moisture content, and cooking loss. From the textural properties measured by texture analyzer, the noodles with 30% barley flour and ${\beta}$-glucan enriched fraction were similar to 100% wheat noodle in springiness value and significantly higher in gumminess, hardness, and chewiness. The results of sensory evaluation indicated that barley flour or ${\beta}$-glucan enriched fraction at levels up to 30% could be substituted for wheat flour without seriously depressing noodle quality. Cooking of raw noodle with ${\beta}$-glucan enrichment slightly increased total, insoluble, and soluble ${\beta}$-glucan content.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.6 no.3_4
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• pp.101-111
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• 1973

To study the effect of freezing rate on the duality of frozen abalone(Haliotis gigantea, GMELIN) liquid nitrogen spray freezing, air blast freezing, semi-air blast freezing, and still air freezing were carried out. The rheological change, protein denaturation, and free water content of frozen and thawed abalone were examined at the period of 0, 1, 2, and 3 month during cold Storage at $-20^{\circ}C$. The results are summarized as follows : 1. The onset and duration of rigor mortis of fresh abalone was faster and shorter as compared to that of fishes. 2. There was no difference in compression value and shear value between freezing methods but they varied with a slight decrease in storage period. 3. Gradual decrease in extractibility of salt soluble protein was observed in all samples except those frozen with liquid nitrogen. 4. The free water of the foot muscle remained constant during the storage while that of the adductor muscle tended to increase. 5. A significant correlation was observed among the changes of panel texture and free water (P< 0.01), protein denaturation (P<0.05), and compression value (P<0.01).

• Korean Journal of Food Science and Technology
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• v.19 no.1
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• pp.75-80
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• 1987

In order to prevent browning during drying of garlic flakes, the effect of dipping in phosphate complex solution prior to drying on the development of brown pigment in the flakes were studied. The browning color development during drying of the flakes was greatly dependent on phosphate complex concentration and their dipping time. A reciprocal relationship between browning color formation and reducing sugar content of dried garlic flakes was found. The browning color development during drying of the flakes was effectively impeded by dipping in 0.3% phosphate complex solution for 3 minute. The reduction of pyruvate content during drying of the flakes was greatly influenced by phosphate complex concentration and drying temperature, and a maximum retention was acieved by 3 minute dipping in 0.2-0.3% phosphate complex solution. The dried yield of the flakes dipped in phosphate complex solution was 1.62-1.75% lower than control and it was mainly caused by the dissolution of soluble solids during dipping.

• Resources Recycling
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• v.3 no.1
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• pp.32-37
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• 1994

Mercury in spent button type batteries can be separated and recovered with vacuum distillation method. It was found that mercury in the battery began to distill at $150^{\circ}C$ and organic substanced like a packing material was decomposed at$ 300^{\circ}C$. More than 99.9% of mercury contained in the battery was distiled and separated at about $250^{\circ}C$ and 20 torr with 8 hours' reaction time. The dissolution tests of the residue after distillation showed that mercury concentration in the solution were lower than 5 ppb and this values satisfied the environ-mental condition. Also as the furnace heating rate was above $15^{\circ}C$/min, it was found that the spent battery was destroyed because of increased pressure in the battery inside.

• Horticultural Science & Technology
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• v.18 no.5
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• pp.612-620
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• 2000

In developing soil wetting agent using polyoxyethylene octylphenyl ether [$C_8H_{17}O(C_2H_4O)_{10}H$, POE], the effect of mixtures of POE and polyoxyethylene+polypropyleneoxide tridecylether (1:1, w/w, CM-1), polyoxyethylene+polypropyleneoxide tridecylether+propyleneglycol monomethylether (1:1:2, w/w/w, CM-2) or glycerin+ditridecyl phthalate (1:1, w/w, CM-3) on changes of concentration of POE, initial wetting, evaporative water loss, water infiltration, and changes of physical properties in root media were determined. The mixtures of POE and CM-1, 2, or 3 with zeolite or vermiculite as carrier had high concentrations of POE in root media during 6 elution times, but those after 6 times decreased rapidly indicating unstable elution of POE. The commercial AquaGro was more effective than the mixtures of POE+CM-1, 2, or 3 in water retention during 18 hours. Root media incorporated with POE+CM-2 held more water than any other treatments at 84 hours after watering, but the differences among treatments except control were not significant. In the treatments with zeolite as a carrier, POE+CM-3 had the greatest evaporative water loss followed by POE+CM-2, AquaGro, control, and POE+CM-2. In the treatments with vermiculite as a carrier, POE+CM-1 had the highest evaporative water loss followed by POE+CM-3, AquaGro, control, and POE+CM-2. In the effect of mixtures with zeolite as a carrier on infiltration of water into root media, the treatment of POE+CM-1 had the highest amount of water infiltrated followed by POE+CM-3, AquaGro, POE+CM-2, and control. In the effect of mixtures with vermiculite as a carrier on infiltration of water into root media, the treatment of POE+CM-3 had the highest amount of water infiltrated followed by AquaGro, POE+CM-1, POE+CM-2, and control.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.1
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• pp.54-60
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• 2006

[ $MnO_2$ ]-Coated Sand(MCS) was prepared with variation of coating temperature, coating time, and dosage of initial Fe(III) with two kinds of sands such as Joomoonjin and quartz sand. An optimum condition for the preparation MCS was determined from the coating efficiency as well as the oxidation efficiency of As(III). Coating efficiency of Mn was strongly dependent on the coating temperature but quite similar over the investigated coating time, showing an increased coating efficiency at higher coating temperature. In contrast to coating efficiency, the oxidation efficiency of As(III) by MCS was severely reduced as increase of coaling temperature. By considering these results, an optimum coating temperature and time for the preparation of MCS was selected as $150^{\circ}C$ and 1-hr, respectively. Coating efficiency increased as the dosage of initial Mn(II) increased, while As(III) oxidation was maximum at 0.8 Mn(II) mol/kg sand. The solution pH was identified as an important parameter affecting stability of MCS, and dissolution of Mn from MCS increased as pH decreased. Oxidation rate of As(III) increased as the dosage of MCS increased as well as solution pH decreased.