• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.05a
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• pp.383-384
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• 2001

환경수의 변화중 염분변화는 어체의 삼투압의 변화를 유도하고, 이때 어류는 염분 변화에 대처하기 위하여, 항상성(homeostasis) 유지측면의 삼투압 조절을 한다. 이러한 환경수의 염분변화에 따라 어류는 일정한 체내 삼투압 유지를 위하여 수분과 세포 내 염류 및 영양물질의 농도를 조절하려고 한다. 해산어류의 삼투압 조절기능을 응용하여 담수순화에 관한 연구보고는 숭어에서 수행되어 왔으나(장과 허, 1999; 허와 장, 1999), 다른 어류에 관한 자료는 부족한 실정이다. (중략)

• Journal of the Society of Cosmetic Scientists of Korea
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• v.26 no.1
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• pp.139-148
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• 2000

The osmotic pressure is a one of the most important factor affecting stabilization of multiple emulsion in a law hours after experiment. To understand and decrease osmotic pressure between Wl phase and W2 phase, a kinds of humectants were introduced in outer water phase. As a result, Betaine and Glucose had an excellent effect reducing osmotic pressure and NaCl made W/O/W emulsion more stable than MgSO4 did when introduced in inner water phase.

• Korean Journal of Microbiology
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• v.42 no.4
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• pp.299-305
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• 2006

D-Alaninepeptidase purified from Bacillus amyloliquefaciene CMB01 caused a reduction of survival of Proteus vulgaris, Klebsiella oxytoca, and Staphylococcus aureus placed under the osmotic pressure. D-Alaninepeptidase caused an increase of susceptibility of bacteria to antibiotics. An increased number of malformed cells in bacterial groups exposed to D-alaninepeptidase was observed by scanning electron microscopy. These data suggested that bacterial cells exposed to D-alaninepeptidase resulted in an increase of vulnerability of bacterial cells toward environmental stress, such as osmotic pressure and antibiotic substances.

• Proceedings of the Membrane Society of Korea Conference
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• 1991.04a
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• pp.27-30
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• 1991

역삼투공정은 선택적 투과성을 가진 막을 이용하여 혼합용액으로부터 특정물질을 분리, 농축 또는 정제하기 위하여 널리 응용되는 분리막기술중의 하나이며, 연속공정이 용이하고 단순히 압력만을 가하는 물리적 조작이므로 원리 및 장치가 간단하여 해수 담수화, 폐수처리, 유용물질 회수, 초순수제조, 식품 및 의약품의 분리, 농축 등 여러 산업분야에서 응용되고 있다. 그러나 매우 큰 삼투압을 나타내는 용액의 농축을 위해서는 삼투압보다 큰 적용압력을 가해주어야 하나 사용된 막은 일정압력 이상에서는 수축되어 제기능을 발휘하지 못하게 되므로 일반적인 역삼투공정으로써는 큰 삼투압을 나타내는 용액의 농축에는 사용될 수 없다. 이는 용액의 삼투압이 씨스템에서 가해줄 수 있는 압력보다 커지기 때문으로, 이 삼투압차를 줄여줄 수 있다면 같은 압력에서도 더 큰 농축효과를 얻을 수 있다.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.10a
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• pp.259-260
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• 2001

양식장에서 사육수의 염분변화는 어체의 삼투압변화를유도함으로써, 어류는 항상성을 유지하기 위하여 삼투압조절 즉, 수분과 세포내 염류 및 영양물질의 농도를 조절하려고 한다. 최근에는 해산어류의 삼투압 조절기능을 응용하여 담수순화 양식을 시도하려는 연구가 숭어에서 수행된 바 있으나(장과 허, 1999; 허와 장, 1999), 이외의 해산어류에 관한 삼투압조절 기능을 연구한 결과는 부족한 실정이다. (중략)

• KOREAN JOURNAL OF CROP SCIENCE
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• v.26 no.2
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• pp.157-166
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• 1981

Laboratory experiements were conducted to evaluate water uptake and osmotic potential of soybean seeds associated with germinability. Bonus, Wayne, Essex and Pickett were selected for this study. Large and small seeds from the four varieties were included in water uptake measurements at $25^{\circ}C$ There were significant differences in water uptake during germination due to seed size and cultivars at optimum moisture condition, -6 and -15 bars soil moisture. As water stress increased, the water uptake of Pickett and Essex were superior to Bonus and Wayne, and small seeds were superior to large seeds. The seed moisture content at germination was 60.8% on a fresh weight basis under optimum moisture condition. The minimum moisture contents necessary for the germination were 50.2% at -6 bars and 50.9% at -15 bars. There were significant differences among varieties in seed osmotic potential during germination, although these differences depended on imbibition time. The average osmotic potential ranged from -32.0 bars after 4 hours imbibition to -11.2 bars at the beginning of germination. The correlation coefficient between seedling length and osmotic potential was not significant after any period of imbibition, suggesting that osmotic potential is not directly associated with seedling growth. However, osmotic potential is closely related to water uptake capacity of soybean seed.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.6
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• pp.848-852
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• 2011

The aim of our study was to develop drying process of apple slice. Quality characteristics of apple slices dried by hot-air and freeze drying after osmotic dehydration was investigated in different sucrose solution (20, 40, $60^{\circ}Brix$) and steeping time (2, 4, 8 hours). The weight of apple slice before and after osmotic dehydration was measured for characteristic of mass transfer. Consequently, osmotic dehydration increases weight reduction, water loss and solid gain of apple slice as the concentration of the sucrose solution and steeping time increased. Moisture contents of apples slices dried hot-air and freeze were about 3 to 7%. Hunter color L, a, b value was lower than non-treatment to osmotic dehydration of apple slice. In hot-air drying, L value decreased as the concentration of the sucrose solution and steeping time increased. The hardness increased as the concentration of the sucrose solution and steeping time increased. Contents of monosaccharide (glucose, fructose) decrease by osmotic dehydration but sucrose increased. In comparison with hot-air drying, freeze drying was high in contents of free sugar.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.39 no.6
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• pp.471-475
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• 2015

Because of increasing demand, a small portable drug injector that uses osmotic pressure for its operation force is developed, and its performance is evaluated. The osmotic drug injector can be small and lightweight because it does not require heavy batteries and an actuator, unlike previous electromechanical drug injectors. Moreover, its injection pressure can be sustained longer than that of previous elastic drug injectors. The new device is composed of a drug sac, osmotic pressure chamber, semipermeable membrane, and solvent chamber. To evaluate its performance, an in-vitro experiment was designed to measure the outflow and the injection pressure with respect to time. The experimental results show that the new drug infuser can continuously deliver 20 ml drug over a period of 20 h. The maximum injecting pressure was over 400 mmHg. Which prevents backflow caused by changes in the outlet pressure resulting from changes to the position of the device and the patient's posture.

• Reproductive and Developmental Biology
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• v.29 no.3
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• pp.169-174
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• 2005

This study was comducted to examine the effects of culture medium, and the osmolarity and osmotic change of the culture medium on in vitro maturation of porcine oocytes and developement of porcine parthenogenetic embryos. In Experiment 1, cumulus-oocyte complexes were matured in NCSU-23, mWM and mKRB, respectively, There was no difference in maturation rate($62.1\~71.3\%$) among groups. In Experiment 2, matured oocytes in each medium were activated and cultured for 6 days in the same media. Blastocyst formation rate was higher in NCSU-23($22.9\%$) than those of others($0\~0.6\%$, P<0.05). In Experiment 3, parthenogenetic embryos were cultured for 6 days in NCSU-23 with different osmolarity(300, 280 and 256 mOsmols) adjusted by NaCl. There were no differences in development rates to the blastocyst stage($11.0\~14.4\%$) among groups. In Experiment 4, activated oocytes were cultured for 2 days in NCSU-23 with 300, 280 and 256 mOsmols and then transferred to increased or decreased osmotic condition. Blastocyst formation rate was higher in a group which was transferred from the higher osmotic condition to the lowe. osmotic condition($21.0\%$) than a contrary group( $11.8\%$, (P<0.05). This result shows that the culture medium and the osmolarity of the culture medium affect the development of porcine parthenogenetic embryos, and the change of osmolarity from the higher condition to the lower condition at a certain developmental stage can enhance the development of porcine parthenogenetic embryos.

• Proceedings of the Membrane Society of Korea Conference
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• 1997.04b
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• pp.3-10
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• 1997

제염농축공정은 증류, 증발법을 일반적으로 사용하나, 에너지 절약차원에서 전기투석 (Electro dialysis)장치를 증발기 선단에 도입한 복합공정을 국내에서도 사용하고 있는 실정이다. 그러나, 전기투석장치는 전기적인 소모와 막의 재생, 교체처리비가 문제점이 되므로 역삼투 장치를 제염농축 공정 최선단에 도입한 복합공정을 이용할 경우 전기 투석 및 증발 복합공정에 비해 40%의 에너지 절감 효과를 기대할 수 있다. 이와 같은 장점에도 불구하고 역삼투 공정은 공급용액의 삼투압보다 큰 적용압력을 막표면에 가하여 물질분리를 수행하므로 농축공정에서 유발되는 배제액 농도의 상승은 삼투압의 증가를 일으켜 실적적용압력의 효과를 떨어뜨리게 되며 결과적으로 농축효과를 감소시키게 된다. 본 연구에서는 효과적인 염농축 공정을 위하여 막모듈 투과부에 고농도 삼투압 감소액(osmotic sink solution)을 향류식(막투과흐름을 맞받아치며 흐르는 방식)으로 유입시키는 향류식 역삼투 (counter-current reverse osmosis, CCRO) 나권형 모듈을 고안 제작하였으며, 제작된 모듈을 기존 역삼투 공정과 향류식 염삼투 공정에 적용하여 염농축도의 성능을 상호 비교하고 염농축에 관계되는 공급농도, 공급유량, 투과유량, 배제유량, 향류 유입유량, 압력구배, 삼투압차 및 농축단수 등의 인자들을 이용하여 두 공정에 대한 염농축 분리조작의 제반조건과 제작된 모듈 내의 농축관련 특성을 실험 및 수치적으로 비교, 고찰하였다.