• Journal of the Korean Society of Clothing and Textiles
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• v.25 no.8
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• pp.1444-1452
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• 2001

Textile materials are frequently in contact with surfactant solutions during their manufacturing or finishing processes as well as cleaning processes in use. Liquid wetting, wicking and absorbency of textile materials, and the liquid properties, surface characteristics and pore geometry of textile materials, and the liquie-solid interactions, In this paper, 10 different nonionic surfactants, including Span 20, Twen 20, 40, 60, 80, 21, 61, 81, 65, 85, were used. The surfactants were characterized by their hydrophile-lipophile-balance (HLB) values, structures, and surface tensions. The 0.1g/dL and 1.0g/dL surfactant solutions, which were both above critical micelle concentration (CMC), were used to see the concentration effects on the wetting and absorbency of cotton fabrics. The wetting behavior and liquid retention properties of hydrophobic cotton fabrics with different nonionic surfactant solutions are reported. The contact angles are greatly decreased and the water retention values are greatly increased by adding most of the surfactants studied into the system. The extents of this effects are influenced by the characteristics of surfactants and its solutions. Hydrophilic surfactants which have low number of carbon atoms or unsaturated hydrophobe structures are more effective in improving the wetting and absorbancy of hydrophobic cotton fabrics. The water retention of hydrophobic cotton fabrics has positive relations with $cos{\theta}$, adhesion tension and work of adhesion. The 1.0g/dL surfactant solutions show similar, but slightly improved wetting and absorbency characteristics of hydrophobic cotton fabrics compared to the 0.1g/dL surfactant solutions.

• Journal of Microbiology and Biotechnology
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• v.22 no.12
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• pp.1705-1713
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• 2012

A gene encoding ${\beta}$-glucosidase was cloned from Weissella cibaria 37, an isolate from human feces. Sequence analysis showed that the gene could encode a protein of 415 amino acids in length, and the translated amino acid sequence showed homology (34-31%) with glycosyl hydrolase family 1 ${\beta}$-glucosidases. The gene was overexpressed in E. coli BL21(DE3) using pET26b(+) and a 50 kDa protein was overproduced, which matched well with the calculated size of the enzyme, 49,950.87 Da. Recombinant ${\beta}$-glucosidase was purified by using a his-tag affinity column. The purified ${\beta}$-glucosidase had an optimum pH and a temperature of 5.5 and $45^{\circ}C$, respectively. Among the metal ions (5mM concentration), $Ca^{2+}$ slightly increased the activity (108.2%) whereas $Cu^{2+}$ (46.1%) and $Zn^{2+}$ (56.7%) reduced the activity. Among the enzyme inhibitors (1 mM concentration), SDS was the strongest inhibitor (16.9%), followed by pepstatin A (45.2%). The $K_m$ and $V_{max}$ values of purified enzyme were 4.04 mM and 0.92 ${\mu}mol/min$, respectively, when assayed using pNPG (p-nitrophenyl-${\beta}$-D-glucopyranoside) as the substrate. The enzyme liberated reducing sugars from carboxymethyl cellulose (CMC).

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.481-481
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• 2007

This work describes the effect of the number of roll pressing and the composition of carbon black on the electric and mechanical properties of carbon-PTFE electrode, in which composition is MSP 20 : carbon black: PTFE = 95-x : x : 5 wt.%. It was found that the best electric and mechanical properties were obtained in sheet electrode roll-pressed for about 15 times and in sheet electrode, in which composition is MSP 20 : carbon black: PTFE = 80 : 15 : 5 wt.%. These behaviors could be explained by the network structure of PTFE fibrils and conducting paths linked with carbon blacks, respectively. On the other hand, cell capacitor using the sheet electrode with 15 wt.% of carbon black attached on aluminum current collector with the electric conductive adhesive, in composition is carbon black : CMC = 70 : 30 wt.%, has exhibited the best rate capability in the current range of $0.5mA/cm^2$ $100mA/cm^2$ and the lowest equivalent series resistance.

• Macromolecular Research
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• v.15 no.5
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• pp.437-442
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• 2007

Poly(ethylene glycol) methyl ether (PEG)-poly(${\beta}$-amino ester) (PAE) block copolymers were synthesized using a Michael-type step polymerization, and the construction of pH-sensitive polymeric micelles (PM) investigated. The ${\beta}$-amino ester block of the block copolymers functioned as a pH-sensitive moiety as well as a hydrophobic block in relation to the ionization of PAE, while PEG acted as a hydrophilic block, regardless of ionization. The synthesized polymers were characterized using $^1H-NMR$, with their molecular weights measured using gel permeation chromatography. The $pK_b$ values of the pH-sensitive polymers were measured using a titration method. The pH-sensitivity and critical micelle concentration (CMC) of the block copolymers in PBS solution were estimated using fluorescence spectroscopy. The pH dependent micellization behaviors with various bisacrylate esters varied within a narrow pH range. The critical micelle concentration at pH 7.4 decreased from 0.032 to 0.004 mg/mL on increasing the number of methyl group in the bisacrylate from 4 to 10. Also, the particle size of the block copolymer micelles was determined using dynamic light scattering (DLS). The DLS results revealed the micelles had an average size below 100 nm. These pH-sensitive polymeric micelles may be good carriers for the delivery of an anticancer drug.

• Archives of Plastic Surgery
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• v.36 no.5
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• pp.543-547
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• 2009

Purpose: Adhesion is the most common and troublesome complication after repair of flexor tendon injury. Recently, use of sodium hyaluronate derivatives for adhesion prevention is increasing. A commercial product, Guardix$^{(R)}$, sodium hyaluronate(NaHe) combined with carboxymethylcellulose(CMC) has been newly developed as a preventive material for adhesion. We have investigated its effect in rabbits. Methods: Twenty seven male New Zealand white rabbits were operated under ketamine anesthesia. After tendon repair in zone II of the hind paw, Guardix$^{(R)}$(experimental group) or normal saline(control group) was administered. Biomechanical tests were performed to estimate adhesion formation at 2, 4, 8, and 12 weeks after the operation. Maximum tensile load to flex the distal interphalangeal joint 50 degree from its resting state(MTL50) was measured, depicting the amount of adhesion formed. Subsequently, breaking strength was assessed. Results: There were no postoperative complications such as infection, wound dehiscence, or hematoma. MTL50 was significantly lower in the experimental group than in the control group at 4, 8, 12 weeks (p<0.05). Mean value of MTL50 was 6.64N in the experimental group and 28.53N in the control group at 12 weeks after surgery. There were no significant differences in breaking strength. Conclusion: Our results indicate that Guardix$^{(R)}$ is helpful in reducing adhesion formation and does not interfere with normal healing processes of the tendon.

• Journal of the Korean Wood Science and Technology
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• v.22 no.2
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• pp.30-36
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• 1994

Steam explosion process is one of the most efficient, pretreatment method for the utilization of lignocellulosic biomass. The carbxymethyl-cellulose(CMC) was prepared with steam exploded wood(EXW), pine(Pinus densiflora) and oak(Quercus mongolica), by standard method using isopropyl alcohol and monochloroacetic acid. The range of water solubility of carboxymethylated pine exploded wood was 45.2~66.8 % and those of oak was 60.7~84.7 %. The degree of substitution(D.S) of carboxymethylated pine exploded wood was 0.11~0.33 and oak exploded wood was 0.48~0.76. The color of carboxymethylated pine and oak exploded wood was brown-black. When carboxymethylated EXW was purified by sulfuric acid, the yield of carboxymethylated wood was lower than non-treated one. However, the color was still brown-black although after delignification. In carboxymethylated EXM prepared after delignification, the water solubility and degree of substitution(D.S) of pine were 81.4~95.9 % and 0.71~0.79, and those of oak were 76.2~89.5 % and 0.79~1.05. The values were higher than non-treated. The degree of substitution of purified carboxymethylated wood prepared with delignified EXM, pine and oak were 0.50~0.71 and 0.70~0.88. The color of carboxymethylated wood was white. In carboxymethylated wood preparde after delignification of EXM, swelling ratio and water retention value of pine were 95.9~96.5 and 580.0~751.2, those of oak were 76.2~89.5 and 124.3~307.6.

• Journal of the Korean Society for Library and Information Science
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• v.49 no.4
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• pp.203-220
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• 2015

This study was to suggest the creation of hybrid bibliographic records in complicated bibliographic environment applying both AACR2 and RDA for uniform display and correct search. The literature reviews and case studies were used as the research methods. In case studies, Kent State University, University of Houston as the libraries, and Backstage Library Works as algorithm converting to hybrid records were surveyed. For creating the hybrid records, it was needed to differentiate hybrid records and born RDA records, to keep the data that appeared in 250 tag without spelling out edition data, to maintain 260 tag instead of converting 260 tag to 264 tag, and last to design mapping table for converting GMD to CMC. This study would suggest uniform display and search through hybridization of bibliographic records of foreign resources.

• Korean journal of food and cookery science
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• v.12 no.2
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• pp.193-199
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• 1996

Effects of addition of various additives, sucrose fatty acid ester 1170 (SE), carboxymethyl cellulose (CMC) and soy bean oil (SO) on textural characteristics for untreated and defatted corn and mung bean starch gels stored at room temperature for 24 hrs and 72 hrs were studied. In sensory and instrumental characteristics of starch gels with additives (0.5% for starch basis), the acceptability was highly correlated with cohesiveness and bend property of starch gels stored 24 hrs and springiness, cohesiveness, color, smoothness, bend property, hardness and clarity of starch gels stored 72 hrs. Regardless of adding additives, textural characteristics of defatted corn starch gels showed somewhat higher values than that of com starch gels. The acceptability of starch gels with additives was somewhat lowered in all the cases, which showed highly correlated in cohesiveness for 24 hrs and springiness for 72 hrs. Instrumental characteristics were similar to those of sensory evaluation, which showed no significant difference with additives.

• Journal of the Korean Applied Science and Technology
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• v.18 no.2
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• pp.111-117
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• 2001

Density, viscosity, conductance, dye solubility and carbon-13 nmr studies were performed in aqueous solution of three disodium 4-n-alkyl-3-sulfonatosuccinate anionic surfactant at $20^{\circ}C$. The cmc values were 0.14 mol/l for the disodium-4-n-octyl-3-sulfonatosuccinate($R_{8)S$), 0.041mol/l for the disodium-4-n-decyl-3-sulfonatosuccinate($R_{10}S$), and 0.018mol/l for the disodium-n-dodecyl-3-sulfonatosuccinate <$R_{12}S$). The aggregation numbers determined viscometrically and conductimetrically were 28 for $R_{8}S$, 48 for $R_{10}S$, and 67 for $R_{12}S$. The volume changes upon micellization were $8.9cm^{3}/mol$ for $R_{8}S$, $9.5cm^{3}/mol$ for $R_{10}S$, and $10.1cm^{3}/mol$ for $R_{12}S$. Binding constants for the dye pada to the micelles and the fractions of unbound counter-ion were also obtained. The two polar heads with their carbon linkage were likely in an aqueous environment in the $R_{8}S$ micelles with the micelles themselves being spherical.

• Preventive Nutrition and Food Science
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• v.3 no.2
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• pp.143-151
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• 1998

Protein -surfactant interactions have been investigate by measuring ζ-potential of $\beta$-lactoglobulin-coated emulsion droplets and $\beta$-lactoglobulin in solution in the rpesenceof surfactant, with particular emphasis on the effect of protein heat treatment(7$0^{\circ}C$, 30min). When ionic surfactant (SDS or DATEM) is added to the protein solution, the ζ-potential of the mixture is found to increase with increasing surfactant concentration, indicating surfactant binding to the protein molecules. For heat-denatured protein,it has been observed that the ζ-potential tends to be lower than that of the native protein. The effect of surfactant on emulsions is rather complicated .With SDS, small amounts of surfactant addition induce a sharp increase in zeta potential arising from the specific interaction of surfactant with protein. With further surfacant addition, there is a gradual reductio in the ζ-potential, presumably caused by the displacement of adsorped protein (and protein-surfactant complex) from the emulsion droplet surfac by the excess of SDS molecules. At even higher surfactant concentrations, the measured zeta potential appears to increase slightly, possibly due to the formation of a surfactant measured zeta potential appears to increase slightly, possibly due to the formation of surfactant micellar structure at the oil droplet surface. This behaviour contrastswith the results of the corresponding systems containing the anionic emulsifier DATEM, in which the ζ-potential of the system is found to increase continuously with R, particularly at very low surfactant concentration. Overall, such behaviour is consisten with a combination of complexation and competitive displacement between surfactant and protein occurring at the oil-water interface. In addition, it has also been found that above the CMC, there is a time-dependent increase in the negative ζ-potential of emulsion droplets in solutions of SDS, possibly due to the solublization of oil droplets into surfactant micelles in the aqueous bulk phase.