• Applied Chemistry for Engineering
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• v.7 no.1
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• pp.129-135
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• 1996

The entrapping capacity of the single hydrocarbons and the entrapping equilibrium data for binary mixtures of the $C_6$ to $C_9$ hydrocarbons on the activated thiourea have been investigated. The entrapping capacity of single component varied irregularly with molecular size and was independent of temperature. In the liquid phase entrapping from binary system, the lower molecular weight hydrocarbon was entrappe preferentially. In the liquid phase entrapping from trimethylbenzene isomer and ethyltoluene isomer, selectivity was found to be related to the relative position of methyl groups in the molecules and hence the electronic configuration. Pseudocumene of a purity of 99.5wt% may be obtained from $C_9$ aromatic raffinate found in naphtha cracking center. Activated thiourea was more efficient than distillation, extractive crystallization and adductive crystallization in terms of separation factor.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.39 no.1
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• pp.56-62
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• 2003

To investigate the entrapping behavior of blue crab, rock shell and green ling, which are mainly caught with the other trap nets in the coastal area of Yellow Sea, by the using duration of trap nets through the water tank experiment. We select the three kinds of trap nets which have different using duration such as new, 6 months and 12 months used one, and observe the entrapping ratio into the trap nets, respectively. In the mean while, in order to obtain the basic data for the estimate of mesh selectivity of the other trap nets, the entrapping behavior into the trap nets for green ling which has high activity compared to blue crab and rock shell, are examined to the three kinds of mesh size (35mm, 50mm and 65mm). The results are as follows ; 1. The mean entrapping ratio of blue crab by the using duration of trap nets in high with 4.4 fishes (44.0%) in the 6 months used one, become lower with 2.9 fishes (28.0%) in the new one, and with 2.0 fishes (20.0%) in the 12 months used one. 2. The mean entrapping ratio of rock shell by the using duration of trap nets in high with 7.3 fishes (36.7%) in the new one, and become lower with 7.2 fishes (35.8%) in the 6 months used one, and with 5.7 fishes (28.3%) in the 12 months used one. 3. The mean entrapping ratio of green ling by the using duration of trap nets in high with 3.4 fishes (34.0%) in the 6 months used one, and become lower with 3.0 fishes (30.0%) in the new one, and with 2.8 fishes (28.0%) in the 12 months used one. 4. The mean residual ratio of green ling by the mesh size of trap nets is high with 2.4 fishes (24.0%) in the 35mm mesh size, and become lower with 2.2 fishes (22.0%) in the 50mm mesh size and 2.0 fishes (20.0%) in the 65mm mesh size.

• Journal of Pharmaceutical Investigation
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• v.30 no.1
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• pp.13-19
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• 2000

$Stealth^{\circledR}$ liposomes entrapped with streptokinase were prepared to improve the physical stability of conventional liposomes. The particle size distribution, dissolution rate and entrapping efficiency of the $Stealth^{\circledR}$ liposomes were studied. The entrapping efficiency of streptokinase into conventional liposomes was proportional to the total lipid and cholesterol amounts. In $Stealth^{\circledR}$ liposomes, the entrapping efficiency of streptokinase was increased with the increase of DPPE-PEG(5,000) amount. The particle size of $Stealth^{\circledR}$ liposomes decreased with the increase of DPPE-PEG(5,000) amount. The dissolution rate of streptokinase from conventional liposomes was decreased by addition of cholesterol. The dissolution rate of streptokinase from the $Stealth^{\circledR}$ liposomes was also decreased by addition of DPPE-PEG(5,000).

• Korean Journal of Clinical Pharmacy
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• v.5 no.2
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• pp.75-84
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• 1995

Drug delivery by red cells was established to maintain the release of drugs in the blood. The entrapment method by amphotericin B was re-examined and evaluated for obtaining the suitable entrapping conditions without hemolysis. The amphotericin B treatment below $10{\mu}g/ml$ induced the non-hemolysis to entrap daunorubicin into red cells within 10min. Under these conditions intracellular ATP level was decreased as $18\%$. Membrane fluidity and the shape factor of red cells were maintained. To maintain intracellular ATP, ATP and sodium pyruvate were added during the entrapment procedure because hemolysis during the release test would reflect the loss of intracellular ATP that would be postulate the decrease of the viability invivo. Consequently, the addition of ATP in the reaction solution can raise the intracellular level of ATP.

• Bulletin of the Korean Chemical Society
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• v.18 no.7
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• pp.761-766
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• 1997

Phospholipase C from Clostridium perfringens is known to catalyze the hydrolysis of phospholipids in biological membranes. In this study, a simple and sensitive method for assaying phospholipase C was developed by using liposomes entrapping calcein as a fluorescent marker. Phospholipase C-induced lysis of liposomes was determined by measuring the fluorescence intensity of calcein released out from liposomes, Various liposomes with different compositions were prepared by reverse-phase evaporation method to investigate the effect of liposomal composition on the lytic activity of phospholipase C. The calcein-entrapping efficiency of liposomes was affected by the chain length of fatty acid in phosphatidylcholine constituting liposomes. The lytic activity of phospholipase C was the highest against liposomes prepared with eggPC. The lytic activity decreased with increasing chain length of fatty acid in phosphatidylcholine. Incorporation of cholesterol more than 20% into the liposomal bilayer inhibited the phospholipase C-induced lysis. The lysis of liposomes was more greatly increased by the addition of 10 mM of calcium. The lytic activity of phospholipase C was also affected by the surface charge of liposomes. Taken together, it was concluded that reverse-phase evaporation vesicles composed of dipalmitoylphosphatidylcholine and cholesterol in the molar ratio of 9 : 1 allowed to detect the lowest concentration of phospholipase C (0.10 μg/assay volume). This study suggested that the use of liposomes can provide a simple, sensitive and inexpensive method for assaying phospholipase C.

• Environmental Engineering Research
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• v.24 no.3
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• pp.376-381
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• 2019

In this study, a poly(vinyl) alcohol/sodium alginate (PVA/SA) mixture was used to fabricate core-shell structured gel beads for autotrophic single-stage nitrogen removal (ASNR) using aerobic and anaerobic ammonia-oxidizing bacteria (AAOB and AnAOB, respectively). For stable ASNR process, the mechanical strength and oxygen penetration depth of the shell layer entrapping the AAOB are critical properties. The shell layer was constructed by an interfacial gelling reaction yielding thickness in the range of 2.01-3.63 mm, and a high PVA concentration of 12.5% resulted in the best mechanical strength of the shell layer. It was found that oxygen penetrated the shell layer at different depths depending on the PVA concentration, oxygen concentration in the bulk phase, and free ammonia concentration. The oxygen penetration depth was around $1,000{\mu}m$ when 8.0 mg/L dissolved oxygen was supplied from the bulk phase. This study reveals that the shell layer effectively protects the AnAOB from oxygen inhibition under the aerobic conditions because of the respiratory activity of the AAOB.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1979.04a
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• pp.115.4-116
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• 1979

Acetone-dried cells of Arthrobacter simplex were entrapped in several preparations of hydrophilic urethane prepolymers and their steroid converting ability was examined. SeVeral solvents, such as methanol and propylone glycol, wereeffective for the conversion of hydrocortisone to prednisolone. The stability of the immobilized cells during storage and on repeated reactions was also examined. Thisconvenient entrapping method was also applicable for the immobilization of cellular organelles. yeast peroxisomes. The entrapped peroxi-somessh owed the activities of alcohol oxidase and catalase.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1977.10a
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• pp.198.1-198
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• 1977

Aspergillus nidulans가 생산하는 naringinase를 acrylamide gel을 이용한 entrapping moth길에 의하여 고정화하여 그 고정화 효소의 물리, 화학적인 성질에 대하여 검토한 결과 다음과 같았다. 1) Acrylamide의 농도는 10% 일때 enzyme activity가 가장 좋았다. 2) Immobilized enzyme의 최적온도는 $50^{\circ}C로서$ 유리효소의 경우보다 $10^{\circ}C정도$ 증가 하였고 최적 pH는 유리효소의 경우와 마찬가지로 pH 40이었다.(중략)

• Journal of Yeungnam Medical Science
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• v.41 no.1
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• pp.58-60
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• 2024

• Korean Journal of Veterinary Research
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• v.32 no.2
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• pp.251-258
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• 1992

Liposomal cephalexin was used m the dry period treatment of bovine mastitis due to Staphylococcus aureus. Liposomes were prepared by stable plurilamellar vesicle(SPLV) process. The shape and size of SPLVs were examined by transmission electron microscopy. The entrapping efficiency and stability of SPLVs were determined by high performance liquid chromatography or liquid scintillation counting. The size of SPLVs ranged from 0.1 to $4.01{\mu}m$ in diameter, with an entrapping efficiency of cephalexin of 25.8 %. The formulation of liposomal cephalexin was used for treatment were SPLV-entrapped cephalexin and free cephalexin with total cephalexin concentration of 250mg per quarters. All quarters were infused intramammarily at the end of lactation period by liposomal cephalexin, free cephalexin, or blank liposome with free cephalexin. The number of quarters cured by liposomal cephalexin(14/15 quarters, 93 %) was significantly higher than that by free cephalexin(7/15 quarters, 46%). or by blank liposome with free cephalexin(8/15 quarters, 53 % ) (p<0.05).