• Korean Journal of Food Science and Technology
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• v.23 no.3
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• pp.330-335
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• 1991

The values of water activity in the different concentrations of NaCl and sodium lactate were measured by hygrometer in the water-sorbitol systems. Interaction of NaCl and sodium lactate was evaluated by Raoult's law. The discrepancy between experimental and theoretical value by the Raoult's law was defined as interaction between water-sorbitol and added solutes in the systems. The changes of interacted water and solutes were observed in whole range of water activity. The value of interacted water (water: sorbitol=1 : 1.1241) obtained by added sodium lactate was found to be higher than sodium chloride. The amount of interacted solute reached maximum about Aw 0.87, while the interactions between added solute and sorbitol showed an increasing tendency below Aw 0.87.

• Korean Journal of Materials Research
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• v.15 no.10
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• pp.632-638
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• 2005

To investigate the effect of Mo and Cu contents on tensile strength of cold drawn stainless steel 304H wires, metallographical and mechanical tests were performed for the wire specimens drawn to different drawing strains at room temperature. It was confirmed that the contents of Mo ana Cu have little influence on the tensile strength of drawn specimens, even though the strain induced martensite transformation decreased with increasing the contents of Mo and Cu. These results were explained by the strengthening of the formed martensite itself due to the solid solution effect of interstitial solutes, carbon and nitrogen. The contents of these elements were slightly higher in the specimens containing additionally added Mo and Cu.

• Membrane and Water Treatment
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• v.1 no.1
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• pp.1-12
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• 2010

Membrane distillation process was used for purification of pre-treated natural water (tap water). The rejection of inorganic and organic compounds in this process was investigated. The obtained rejection of inorganic solutes was closed to 100%, but the volatile organic compounds (VOCs) diffused through the membrane together with water vapour. The content of trihalomethanes (THMs) in the obtained distillate was two-three fold higher than that in the feed, therefore, the rejection of the total organic compounds present in the tap water was reduced to a level of 98%. The intensive membranes scaling was observed during the water separation. The morphology and composition of the fouling layer was studied using scanning electron microscopy coupled with energy dispersion spectrometry. The influence of thermal water pre-treatment performed in a heat exchanger followed by filtration on the MD process effectiveness was evaluated. This procedure caused that significantly smaller amounts of $CaCO_3$ crystallites were deposited on the membrane surface, and a high permeate flux was maintained over a period of 160 h.

• Korean Chemical Engineering Research
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• v.53 no.5
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• pp.627-631
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• 2015

Various solid structures were prepared by electrospray technique. In this process, liquid flows out from a capillary nozzle under a high electrical potential and is subjected to an electric field, which causes elongation of the meniscus to form a jet. In our study, by controlling the amount of polyvinyl pyrrolydone in precursor solution, the jet either disrupted into droplets for the formation of spherical particles or was stretched in the electric field for the formation of fibers. During the electrospray process, the ethanol solvent was evaporated and induced the solidification of precursors, forming solid particles. The evaporation of ethanol solvent also enhanced the mass transport of solutes from the inner core to the solid shell, which facilitated fabrication of porous and hollow structure. The network structures were also prepared by heating the collector.

• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.546-549
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• 2000

Liposomes and proteoliposomes, artificial membranes, can interact with many solutes, such as drugs, peptides and proteins. Immobilization of (proteo)liposomes as supramolecular aggregates on gold surfaces have potential applications in nanotechnology and biosensors. We demonstrate a quartz crystal analyzer (QCA) method to monitor the construction of multi layers of unilamellar liposomes based on avidin-biotin binding on gold surface using quartz crystal microbalance(QCM). Thus, QCA provides an on line and efficient method to detect the protein membranes construction and have applications to biosensing system.

• Journal of the Korean Ceramic Society
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• v.17 no.4
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• pp.179-187
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• 1980

Perovskite-type oxide catalysts in the $\textrm{LaMnO}_3$ family were prepared by both freeze drying and precipitation technique, and their catalytic activities with respect to the oxidation of CO with $O_2$ were measured in the composite gases. Freeze drying is a new technique for the prevention of migration of the solutes during drying. Therefore, the corrugated cordierite monolith fabricated with the Ø 1mm stainless steel bar was directly impregnated with nitrate solutions containing the appropriate cations, freeze dried and calcined. Precipitation was done by using $\textrm{(NH_4)}_2\textrm{CO}_3$ but the precipitated catalysts gave lower catalytic than the freeze dried samples due to, in part, relatively high calcining temperature. In this study, freeze dried composition had high catalytic activity, and their apparent activation energy for oxidation of CO was calculated by the rate plots using the data where the percent conversion of CO was less than 20%.

• Progress in Superconductivity
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• v.5 no.1
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• pp.65-69
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• 2003

Many researches on fabrication process for BSCCO precursor powders have been developed for high J$_{c}$ BSCCO-2223 tape. Spray pyrolysis method for fabrication of precursor powder has many advantages, such as high purity, fine particle size and low carbon content of BSCCO precursor powder. Fine, spherical powders were prepared by ultrasonic spray pyrolysis from the aqueous solution of metal nitrates. BSCCO precursor powders were synthesized with various solutes concentration and heat treatment conditions. Average particle size for spray pyrolysis powders was $1.5∼3\mu\textrm{m}$. Bi-2223/Ag tape was prepared by PIT method and followed by various sintering conditions. BSCCO precursor powders were characterized by XRD, SEM, EDS, Carbon content and particle size analysis.s.

• Proceedings of the KOSOMBE Conference
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• v.1997 no.05
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• pp.7-10
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• 1997

Poly(acrylic acid) 와 poly(vinyl alcohol) 을 이용하여 온도와 pH 에 감응성을 가지는 상호침투 가교 고분자 히드로겔을 합성하고 약물의 투과도를 측정하였다. 이 히드로겔은 고분자 구조 내에 이온기를 포함하고 있으므로 팽윤 시에 외부의 pH 와 이온 세기의 영향을 크게 받았으며 이온기와 용액과의 상호작용이 증가할수록 팽윤도가 감소하였다. 히드로겔을 이용한 약물의 투과실험에서 비이온성 약물의 경우 약물 입자의 크기에 따른 분리가 가능하였으며 이온성 약물의 경우 고분자 히드로겔의 구조차 외부 pH, 약물의 구조에 따른 상호작용에 의하여 투과가 이루어짐을 알 수 있었다.

• Membrane Journal
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• v.6 no.2
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• pp.79-85
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• 1996

This study is undertaken to investigate the effect of positive charge on the premeation characteristics of quaternary ammonium polysulfone (AMPS) membrane. AMPS membrane having a hydrophilic property was less fouled than PSf membrane. AMPS membrane had a positive charge and was thought to be able to expel charged solutes, such as basic dyes, proteins and amino acids, having same sign as the membrane surface.

• Journal of the East Asian Society of Dietary Life
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• v.5 no.2
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• pp.19-26
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• 1995

Staphylococcus aureus, the most salt-tolerant nonhalophilic bacterium, is the only foodborne pathogen that is able to grow at a levels below 0.90. The fundamental osmorgulatory strategy used by this organism involves the accumulation of intracellular compatible solutes such as proline or glycine betaine which are accumulated by transport and act as osmoregulators in cells. In this study, levels of proline transport systems and glycine betaine transport system of S. aureus were examined when cells are grown at high osmolarity. The levels of all three transport systems within S. aureus were elevated at high osmolarity and the most dramatic increase was found for the low-affinity proline transport system. However, in 5mM glycine betaine-supplemented medium, the level of the low-affinity proline transport system did not become elevated when cultures were grown at high osmolarity. The metabolic fate of the accumulated proline and glycine getaine was investigated by thin-layer chromatography an found to be not metabolized by S. aureus.