• Archives of Pharmacal Research
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• v.18 no.4
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• pp.224-230
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• 1995

Recently, many attempts have been made to use hydrogels of various polymers as delivery systems of various drugs and bioactive materials to prolong and control their phamacological activities. In this study, we have evaluated the physico-chemical properties of methacrylic acid-methyacrylic acid methyl ester copolymer 9Eudispert mv)m a acrylic resin hydorgel, and its application to transdermal delivery system. In the dissolution tests, the release rate of salicylic acid (SA) and sodium salicylate (SOd. SA) were faster than lidocain (LD) and lidocain-HCl(LD-HCl). As the concentration of Eudispert mv polymer increased, the extensibility of Eudispert mu hydrogel decreased, whereas the swelling ratio increased. The more NaOH and polymer concentration increased, the more osmotic pressure linearly increased. The skin permeation of Sod. SA, an acidic model drug, was remarkably enhanced by Eudispert mv hydrogel. All fatty acids, except for Sod. glycolate, dramatically increased the skin permeation flux in Eudispert mu hydrogel containing LD-Hcl, a basic model drug. Consequently, it is suggested that Eudispert mv hydrogel may be used as potential transdermal delivery vehicle.

• Journal of the Korean Electrochemical Society
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• v.1 no.1
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• pp.55-59
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• 1998

The water absorption in protective coatings, which may greatly influence the durability of these coatings, was studied using quartz crystal microbalance and electrochemical impedance technique. The water absorption in protective coatings and the change of coating capacitance with concentration of electrolyte were measured. The water absorption in coatings seems to be driven by osmotic pressure, and larger amount of water was absorbed in thinner coatings at initial stage of absorption. The amount of water absorbed in coatings changed with the type and crosslinking density of resin used in coating formulation. When water absorption and desorption of coating occured by exposing the coatings to electrolyte solutions of different concentration, increase in impedance caused by desorption of water was found to be higher in the case of thinner film.

• Korean journal of applied entomology
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• v.26 no.3 s.72
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• pp.145-150
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• 1987

Carborhydrate contents were compared between diapausing and non-diapausing pupae of the fall webworm, Hyphantria cunea DRURY. Glycogen content in the whole body of diapausing pupae kept at $-5{\pm}1^{\circ}C$ was less than that of those left at room temperature, while the amounts of trehalose and sorbitol showed the reverse trend. The osmotic pressure of haemolymph was higher in diapausing pupae than that in non-diapausing pupae. The mean oxygen consumption rate of diapausing pupae was $4{\sim}6.7$ times less than that of non-diapausing, normal pupae.

• Korean Chemical Engineering Research
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• v.46 no.4
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• pp.764-768
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• 2008

Bovine testicular hyaluronidase PH-20 was cloned into pPIC9 vector and expressed in Pichia pastoris. Recombinant PH-20 was 75 kDa MW and 7460 units/L activity. Extracellular hyaluronidase activity was two times higher than that of intracellular activity. Non-buffered medium and $30^{\circ}C$ cultivation was favorable for PH-20 production. 1M sorbitol as an osmotic pressure and 0.3% methanol inducer increased cell growth and enzyme activity. 0.4 M arginine augmentation decreased the proteolytic degradation of recombinant hyaluronidase.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.31 no.2
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• pp.173-179
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• 2009

Dentigerous cyst is an odontogenic cyst which occurs in unerupted tooth crown. After the crown formation, enamel epithelium remnants surrounded continuously proliferates and it forms effusionfluid cyst and expands due to increased internal osmotic pressure. Treatments of cysts are mainly enucleation, marsupialization and de-compression. When deciding the way of treatment, the age of a patient, the anatomical circumstances, the region of lesion and the size of cyst should be considered. Marsupialization is that some parts of internal cystic wall would be converted into oral mucosa if the cyst is large size and is concerned about neighboring anatomic structure. It can be accompanied by enucleation later and eruption of related tooth can be possible. If there is a limitation of spontaneous tooth eruption, eruption of tooth can be induced by orthodontic apparatus. There were 3 patients had dentigerous cyst and underwent marsupialization, their impacted teeth had preserved and had induced eruption, all showing satisfactory results.

• Journal of Environmental Science International
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• v.7 no.2
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• pp.209-216
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• 1998

Nanofiltration[NF45] and reverse osmosis membrane(HR98PP) separation treatment of dyestuff wastewater was carried out In order to separate relatively pure water from synthetic dyestuff wastewater, which consists of reactive dye, acid dye, basic dye, direct dye, and disperse dye. The experiments were performed by using the plate and frame membrane module. In the nanofiltration and reverse osmosis membrane separation, When the NaCl concentration was 0.1, 5.0, and 20.091, retention was 63.0, 46.0, 0.9%, respectively. When permeate flux was 125.0, 67.5, and 45.0 L/$m^2$ h, the osmotic pressure increased with Increasing the NaCl concentration. Permeate flux of two membranes Increased as temperature Increased due to segmental movement of polymer of the membrane and the rejection rate of dyestuff was decreased gradually. It was found that the rejection rate was about 95% in the nanofiltratlon, while the reverse osmosis membrane showed a high rejection rate of 99% under all temperature and pressures conditions.

• Korean Journal of Materials Research
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• v.32 no.4
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• pp.230-236
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• 2022

The formation behavior of a passive state film on the surface of STS304 in electrolytic solution was analyzed to determine its metallic ion composition. The properties of passive state films vary depending on the Fe and Cr ions in the electrolytic solution. It was observed that the passive state film surface became flat and glossy as the concentration of Fe and Cr ions in the electrolytic solution increased. The corrosion resistance property of the passive state film was proportional to the amount of Fe and Cr in the electrolytic solution. An initial passive state film with high Fe concentration was formed on the surface of STS304 during early electrolytic polishing. Osmotic pressure of Fe ions occurs between the passive state film and electrolytic solution due to the Fe ion concentration gradient. The Fe in the passive state film is dissolved into the electrolyte, and Cr fills up the Fe ion vacancies. As a result, a good corrosion-resistant floating film was formed. The more Fe ions in the electrolytic solution, the faster the film is formed, and as a result, a flat passive state film containing a large amount of Cr can be formed.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.36 no.1
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• pp.22-33
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• 1991

The studies aimed to distinguish between initial (ionic or osmotic) effects of salinisation on growth and the longer-term consequences of excessive salt accumulation. Tall and dwarf varieties of rice were used to provide different growth rates. There was no significant effect upon the day-to-day pattern of growth, upon the ultimate length of leaves that were developing at the time of, or shortly after, salinisation with 50 mM NaCl. Leaves that developed after prolonged exposure of the plants to salinity were shorter. Addition of NaCl, KCl or mannitol to the root medium brought about a cessation of leaf elongation within one minute. Growth at a reduced rate restarted abruptly after a lag period that depended upon the external concentration. Elongation rate recovered to its original value within 24 hours after exposure to 50 mM NaCl, though not at higher concentrations. Addition of NaCl at concentrations up to 100 mM elicited no short-term effect upon photsynthetic gas exchange. No change in turgor pressure was detectable in the growing zone with the resolution of the miniature pressure probe used (about 70 kPa). It is concluded that the initial growth reduction in rice caused by salinisation is due to a limitation of water supply. A clear distinction is made between the initial effects of salt which are recoverable, and the long-term effects which result from the accumulation of salt within expanded leaves.

• Development and Reproduction
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• v.24 no.1
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• pp.19-30
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• 2020

The pH of water is one of the main environmental factors exerting selective pressure on marine and freshwater organisms. Here, we focus on the influence of pH on an organism's ability to maintain homeostasis and investigate the effects of acidification on immunity-related genes and osmotic pressure during early development of the olive flounder, Paralichthys olivaceus. The aim of our study was to determine the influence of various pH levels on the fertilized eggs and larvae of P. olivaceus. Gametes of P. olivaceus were artificially introduced and the resulting fertilized eggs were incubated at pH 4.0 (low), 6.0, and 8.0 (equivalent to natural sea water; control). We found that all eggs sank from the water column at pH 4.0. After 38 h, these eggs showed slow development. Hatching occurred more slowly at pH 4.0 and 6.0 and did not occur at all at pH 4.0. Result of gene expression, caspase and galectin-1 were expressed from the blastula to pre-hatch stages, with the exception of the two-cell stage. HSP 70 was also steadily expressed at all pH levels over the five days. The osmolality of fertilized eggs differed marginally at each stage and across pH levels. So, this results demonstrates that low pH level is detrimental to P. olivaceus fertilized eggs.

• Journal of Korean Society of Water and Wastewater
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• v.30 no.4
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• pp.401-408
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• 2016

Desalination is getting more attention as an alternative to solve a global water shortage problem in the future. Especially, a desalination technology is being expected as a new growth engine of Korea's overseas plant business besides one of the solutions of domestic water shortage problem. In the past, a thermal evaporation technology was a predominant method in desalination market, but more than 75% of the current market is hold by a membrane-based reverse osmosis technology because of its lower energy consumption rate for desalination. In the future, it is expected to have more energy efficient desalination process. Accordingly, various processes are being developed to further enhance the desalination energy efficiency. One of the promising technologies is a desalination process combined with Pressure Retarded Osmosis (PRO) process. The PRO technology is able to generate energy by using osmotic pressure of seawater or desalination brine. And the other benefits are that it has no emission of $CO_2$ and the limited impact of external environmental factors. However, it is not commercialized yet because a high-performance PRO membrane and module, and a PRO system optimization technology is not sufficiently developed. In this paper, the recent research direction and progress of the SWRO-PRO hybrid desalination was discussed regarding a PRO membrane and module, an energy recovery system, pre-treatment and system optimization technologies, and so on.