• Applied Chemistry for Engineering
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• v.20 no.1
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• pp.9-14
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• 2009

A zwitterionic surfactant shows not only detergency but also softening effect since it shows characteristics of a nonionic or an anionic surfactant above an isoelectric point, while showing characteristics of a cationic surfactant below an isoelectric point. Therefore, a zwitterionic surfactant can serve as a dual function surfactant by a single molecule through the interconversion of cleaning and softening effects depending on pH of the aqueous solution. In this study, the dual function characteristics of an amine oxide zwitterionic surfactant were investigated by measuring the zeta potential and the isoelectric point using quartz crystal microbalance (QCM). In addition, the physical properties of an amine oxide surfactant such as critical micelle concentration, surface tension, interfacial tension, contact angle and viscosity were measured and phase behavior study was also performed. The isoelectric point of an amine oxide surfactant determined by zeta potential measurement was near 7.35 and that obtained by QCM experiment was about 7.4, where both results were found to be close to the value reported in the literature.

• Korean Journal of Veterinary Research
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• v.46 no.4
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• pp.395-398
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• 2006

A 2-month-old female Shih-tzu dog was referred because of lameness, exercise intolerance, depression, elbow and stifle joint swelling. Physical examination, complete blood counts, serum-chemistry, radiography, synovial fluid analysis, antinuclear antibody test, and rheumatoid factor measurement were initiated. On radiography, soft tissue swelling of elbow and stifle joints without erosiveness were founded. The results of synovial fluid analysis revealed severe neutrophilic pleocytosis (nondegenerative), decreased viscosity, increased turbidity, positive on mucin-clot test, and negative on bacterial culture. The results of rheumatoid factor measurement and antinuclear antibody test were negative and below 1 : 40, respectively. Based on all tests, we diagnosed this case as juvenile onset type I immune-mediated polyarthritis. Azathioprine (1 mg/kg body weight, per os q 24 h, for 4 weeks) was then administered and clinical signs improved gradually. Four weeks after azathioprine administration, clinical signs were disappeared. This report describes the clinical findings, imaging characteristics, synovial fluid findings, and other laboratory results of type I immune-mediated polyarthritis and successful management with azathioprine therapy.

• Journal of the Korean Applied Science and Technology
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• v.35 no.1
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• pp.173-185
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• 2018

Effects of three different types of dispersions and flow improving additives composed with fatty acid esters, fatty acid metal salts and amide compound on the vulcanization and the mechanical properties properties of rubber compounds of EPDM and carbon black as fillers. were investigated using Mooney viscometer, moving die rheometer, hardness tester, and universal test machine. The aging characteristics of vulcanized EPDM compounds were also investigated. The Mooney viscosity measured at $125^{\circ}C$ showed a tendency to decrease in the order of amide type> metal salt type > ester type additive. Scorch time showed little or no difference with the addition of ester or metal salt type additives, but the amide type additive shortened a scorch time more than one minute. Rheological measurement data obtained at $160^{\circ}C$ showed that the vulcanization time was faster for metal salt type and amide type additive systems. Delta torque values of EPDM compound increased with metal salt type and amide type additives, but slightly decreased with ester type additive. The tensile strength of the EPDM compound was greatly improved when an ester type additive was added, but the amide type or metal salt type additive had no significant effect. The elongation was significantly improved for metal salt type additive, while the rest were not significantly affected. The tear strength of the EPDM compounds increased with the addition of all kinds of additives, and it increased remarkably in the case of metal salt type additive. Hardness of the EPDM compounds was nearly same value regardless of additive types. The thermal aging of the EPDM blend at $100^{\circ}C$ for 24 h showed little change in the case of metal salt type or amide type additive, but the elongation tends to decrease by 10-20% for all EPDM compounds containing additives.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.20 no.3
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• pp.103-111
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• 2014

This study analyzed effects of packaging materials and storage temperature on the shelf-life of Korean grinded yam. For experimental measurement, experimental groups were used $PET(12{\mu}m)/Al(9{\mu}m)/LLDPE(60{\mu}m)$ as opaque barrier packaging material and $PET(12{\mu}m)/PE(20{\mu}m)/VM-PET(12{\mu}m)/PE(25{\mu}m$) and barrier $NY(15{\mu}m)/LLDPE(60{\mu}m$) as transparent barrier packaging material. Control group were used normal $NY(15{\mu}m)/LLDPE(65{\mu}m)$. The grinded yam stored at refrigeration temperature ($5^{\circ}C$) and room temperature ($20^{\circ}C$C) for 8 days. Changes in color, pH, viscosity, microorganisms and sensory characteristics were measured. In the grinded yam L and ${\Delta}E$ value were not changed rapidly at refrigeration temperature. However L and ${\Delta}E$ were rapidly changed in all of packaging materials at room temperature. In two temperature condition, pH and viscosity were decreased during storage but pH was increased at $5^{\circ}C$ after 4 days. PET/Al/LLDPE and PET/PE/VM-PET/PE inhibited the growth of microorganisms effectively. PET/AL/LLDPE which is a high barrier packaging material showed the best in two temperature condition.

• Journal of the Korean Chemical Society
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• v.45 no.6
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• pp.555-561
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• 2001

Vinyl acetate usually used in PVA resin preparation was converted to PVAc by bulk polymerization using AIBN as a initiator and PVA was synthesized by changing the concentration of NaOH added for saponification subsequently. As a result of estimating molecular weight using GPC, molecular weight increased as the NaOH concentration increased to 2.5 N, 5.0 N, 7.5 N and 10.0 N and polydispersity had similar values of 2.1~2.3, however, showed slightly decreasing tendency. In addition, PVA saponificated by 10.0 N-NaOH showed high syndiotacticity in observation of tacticity using NMR spectroscopy. From this fact, the degree of tacticity was predicted to be high and it was in good agreement with the tendency of polydispersity by GPC. Also, from the result of FT-IR spectroscopy, it might be known that hydrolysis was more promoted in the PVA with 10.0 N-NaOH than other NaOH concentration. Intrinsic viscosity measured using Ubbelohde viscometer, which increased as the concentration of NaOH added for saponification increased. The change of shear strength with the change of shear rate was investigated using Brookfield viscometer, in consequence, viscosity of PVA synthesized decreased as shear rate increased. PVA solution confirmed to show the shear thining behavior by Casson plot and PVA with 10.0 N-NaOH had the largest yield value. DSC measurement was performed to know the thermal properties of PVA. Tp had nearly constant value of 214$^{\circ}C$ in all cases except for adding 2.5 N-NaOH and $\Delta$H was increased as the concentration of NaOH increased. From this properties, it was concluded that the degree of hydrogen bonding was proportional to the added concentration of NaOH and the increase of the degree of hydrogen bonding and hydrophobic interaction could affect the rheological and thermal properties of title compound.

• Korean Journal of Food Science and Technology
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• v.32 no.3
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• pp.590-597
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• 2000

The rheological properties of ${\beta}-glucans$ isolated from non-waxy and waxy barley were investigated. ${\beta}-Glucan$ solutions showed pseudoplastic properties and their behaviors were explained by applying Power law model in the range of concentrations$(1{\sim}4%)$ and temperatures$(20{\sim}65^{\circ}C)$. The effects of temperature and concentration on the apparent viscosity at $700\;s^{-1}$ shear rate were examined by applying Arrhenius equation and power law equation, and their effect was more pronounced in waxy ${\beta}-glucan$ solutions. The activation energy for flow of ${\beta}-glucan$ solutions decreased with the increase of concentration, and the concentration-dependent constant A increased with the increase of temperature. The intrinsic viscosity of waxy ${\beta}-glucan$ was higher than that of non-waxy ${\beta}-glucan$. The transition from dilute to concentrate region occurred at a critical coil overlap parameter $C^*[{\eta}]=0.02.$ The slopes of non-waxy and waxy ${\beta}-glucan$ at $C[{\eta}] were similar, but the slope of waxy ${\beta}-glucan$ at $C[{\eta}]>C^*[{\eta}]$ was higher than that of non-waxy ${\beta}-glucan$. Dynamic viscoelasticity measurement showed that cross-over happened, and storage modulus was higher than loss modulus at frequency range above cross-over. ${\beta}-Glucan$ solutions formed weak gels after stored for 24 hr.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.2
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• pp.245-250
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• 2008

The purpose of this study was to evaluate quality of abalone porridge prepared with different sizes of rice and amounts of added water. pH of porridge was mostly stable from 6.3 to 6.8 but as more water was added, pH increased. Increase of added water resulted in higher TBARS value, but most of TBARS value was generally low, and there wasn't any significant difference. Lightness of the rice powder porridge was 53 to 59 and it was higher than that of round rice porridge. Redness tended to be high as rice size was bigger and less amount of water was added. Yellowness of round rice porridge and half rice porridge was higher than that of rice powder porridge. Also, yellowness of porridge had a tendency to decrease as amount of water was increased. Consistency, viscosity, and firmness was higher in round rice porridge and half rice porridge than in rice powder porridge, and increase in added water amount led to decrease of all textural properties. In the measurement of texture properties that is only present in rice grain, the hardness, gumminess, and chewiness of round rice grain porridge was significantly higher than that of half rice. In the sensory evaluation result, all sensory properties was significantly different (p<0.05) among the abalone porridges prepared with different rice sizes and added water. The viscosity, flavor, texture, and taste of half rice abalone porridge added 1000 mL water showed the highest sensory scores.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.48 no.1
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• pp.1-10
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• 2022

Customized cosmetics are continuously mentioned as a trend in the cosmetics industry to respond to the recent rapid changes in the social environment and pursue individuality and diversity. Accordingly, four types of liposome essence corresponding to skin types were prepared by varying the ratio of liposome formulation and essence formulation as a customized cosmetic base that can be easily mixed and applied at the workplace. The volatilization residues of four types of liposome essence were measured and the nanoparticle size, polydispersity index, zeta potential and viscosity according to time for 90 d were measured, and Turbiscan was measured as a method for evaluating the stability of a colloidal dispersion system. In addition, a simple usability evaluation was performed for four types of liposome essence corresponding to the skin type. As a result, the amount of volatile residue in the four types of liposome essence was increased in dry products rather than oily ones, and the particle size showed a tendency to increase with time in the range of 165 to 175 nm, increasing up to 31.5%, and the polydispersity index was 0.23 to 0.26. There was little change with time, and the zeta potential was -74 to -72 mV, showing a slight decrease with time, but there was little change to the extent of a maximum decrease of 14.0%. Viscosity showed a decreasing trend with time in the range of 2,580 ~ 3,290 cps, showing a maximum decrease of 17.5%. In the turbiscan measurement, all of the turbiscan stability index, a measure of stability, were less than 1.0, indicating dispersion stability. In the overall simple usability satisfaction evaluation for skin types (6 points), products for oily skin (5.33 ± 0.75 points) > products for medium dry skin (5.13 ± 0.95 points) > products for dry skin (5.03 ± 0.96 points) > products for oily skin (4.80 ± 1.04 points) points) were evaluated in order. The four types of liposome essence corresponding to skin types with different ratios of liposome formulation and essence formulation were physically stable, and the possibility of application as a customized cosmetic base according to skin type was confirmed.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.48 no.4
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• pp.343-355
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• 2022

Customized cosmetics are continuously mentioned as cosmetics in response to changes in the social environment and trends that emphasize individuality. Therefore, in this study, four types of nanoemulsion ampoules corresponding to skin types were prepared by different ratios of nanoemulsion formulation and ampoule formulation, and the applicability as a customized cosmetic base was checked. Particle size, polydispersity index, zeta potential, and viscosity according to time for 90 d were measured for four nanoemulsion ampoules with different volatile residues, and turbiscan was measured as a method for evaluating the stability of a colloidal dispersion system. Finally, human usability satisfaction was evaluated. As a result, it was confirmed that four kinds of nanoemulsion ampoules had a higher amount of volatile residue in the dry skin test product than in the oily skin test product. The pH was in the range of 6.41 to 6.88, and the particle size was in the range of 170 to 174 nm, and the change after 90 d was within 1.2% of the maximum, and there was no specificity in particle size stability. It was confirmed that the polydispersity index was almost constant, and showed a particle size distribution close to monodispersity by showing a change within a value smaller than 0.21 in all test products. The zeta potential was initially -63 mV or more for all four types of test products, and although it showed a slight decrease with time, there was little change to the extent of a maximum decrease of 2.5%. Viscosity was initially in the range of 4,100 to 5,100 cps and showed a decreasing trend with time, showing a maximum decrease of 37.7%. In the turbiscan measurement, the turbiscan stability index, a measure of stability, was all below 1.0, indicating dispersion stability. In the usability satisfaction evaluation (6 points) of 4 nanoemulsion ampoules corresponding to skin type, oily skin product (5.42 ± 0.67 points) > neutral oily skin product (5.36 ± 0.67 points) > neutral dry skin product (5.15 ± 0.69 point) > dry skin product (4.75 ± 0.75 points) in the order of evaluation. Four types of nanoemulsion ampoules are physically stable and have confirmed their applicability as a customized cosmetic base according to skin type, and are expected to expand in various ways.

• Korean journal of food and cookery science
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• v.13 no.2
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• pp.204-212
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• 1997

The characteristics of sponge cakes prepared with replacement of 30, 50, 75, or 100% of sucrose with isomaltooligosaccharide (IOS), fructooligosanharide (FOS), maltitol symp (MS), or maltitol powder (MP), were examined through physical measurement and sensory evaluation. The specific gravities of foams and cake batters were not significantly different among samples (p .0.05). The use of IOS increased the viscosity of cake batter. The cakes containing IOS, FOS, MS, or MP were softer than control cakes (sucrose 100%). Especially cakes prepared with 30, 50％ IOS, or 75, 100％ MP, appeared to be fragile. When increasing levels of IOS or FOS were incorporated in the cake formula, cake crust color was getting darker than that of control cake, whereas cake containing maltitol was getting lighter as the levels of replacement increased. Generally, the volume of cake containing FOS were superior to that of control cake, whereas those of cakes containing above 50% MP were inferior. Sensory analysis of experimental cakes did not show significant differences from the control cake for softness, springiness and gumminess. Sweetness increased replacing the sucrose with FOS, MS or MP (30, 50%) and moistness increased using IOS, FOS, MS, or MP without agreement with moisture contents of cakes. Replacement of 30, 50% sucrose with MS or 30％ with MP did not affect greatly the physical measurements or sensory characteristics studied.