• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.3
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• pp.404-408
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• 1995

The effect of processing conditions on the changes in the contents of dietary fiber fractions and its physical properteis of Godulbaegi(Korean lettuce, Ixeris sonchifolia H.) was determined during preparation and fementation for kimchi. Water holding capacity(WHC) and oil adsorption capacity(OAC) were also checked on the subject of freeze dried powder from different stages of the kimchi processing. Neutral detergent fiber(NDF) content in young samples(leaf and root) decreased with prolonged soaking and fermentation period. Every young samples had a higher level in NDF than in ripe samples. Noticeable decrease in acid detergent fiber(ADF) without a change in ripe roots was showed after fermentation($4^{\circ}C$, 60 days). The water holding capacity of freeze dried young plants ranged from 5.78ml/g for roots to 6.31ml/g for leaves. Soaking and fermentation resulted in decreasing WHC and about 50% of WHC(raw leaves) was lowered after kimchi fermentation($4^{\circ}C$, 40 days). OAC of all samples were lower than WHC in same samples significantly and those were also decreased after soaking and fermentations as WHC.

• KSBB Journal
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• v.13 no.2
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• pp.147-154
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• 1998

Enzymatic hydrolysis using an immobilized enzyme was carried out to produce chitosan oligosaccharides (COSs) from chitosan effectively. Chitosanase was immobilized on eight different carriers by physical adsorption. The enzyme immobilized on chitin had higher activity than those immobilized on the other carriers in spite of its lower adsorption. The activity of chitin-immobilized enzyme was more than 90% of the original activity. Optimal temperature of the immobilized enzyme increased by about $15^{\circ}C$ and its thermostability was excellent in relatively wide range of temperature. But its effects of pH did not improve compared to the free enzyme. The immobilized enzyme produced 153 mg/g chitosan of the reducing sugar for 3hrs of hydrolytic incubation time. The total content of higher oligomers, tetramer to hexamer, among amount of total COSs obtained for 2hrs was more than 90%. In kinetic parameters for both enzymes, immobilized enzyme showed lower affinity for substrate and reaction rate than free enzyme, however, no reduction of the rate for high substrate concentrations. Consequently, chitin-immobilized could effectively hydrolyse chitosan and produce the higher COSs without activity decrease in comparison with the free enzyme.

• Journal of the Korean Wood Science and Technology
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• v.40 no.1
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• pp.10-18
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• 2012

A high airtightness is required for the residential spaces constructed recently to save cooling and heating energy through improving insulation performance. Because the chances to release steam formed by human activity in building and inflow of water vapor in outdoor air to residential space are reduced, the natural humidity control performance of interior materials has become more important. In this study, hygroscopic performance of thermo-physically treated wood (Pinus koraiensis) was estimated. At various relative humidity condition, the water vapor adsorption and desorption rates of wooden materials were measured as well as equilibrium moisture content. Effects of roughness and surface microstructure as physical factors and functional groups as chemical factors on the hygroscopicity were analyzed. It is expected that the results from this study and further study of measuring moisture generation in residential spaces could contribute to install a system for evaluating the hygrothermal performance of wooden building.

• Korean Journal of Food Science and Technology
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• v.46 no.3
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• pp.315-322
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• 2014

Immobilized lipases were prepared by physical adsorption using lipase AK, AY, AH, PS and R on Amberlite$^{(R)}$XAD$^{(R)}$7 HP resin. With the immobilized lipases (10%), structured lipid was synthesized by enzymatic interesterification of canola oil, palmitic ethyl ester, and stearic ethyl ester in order to study the reaction characteristics. Among the lipase, the highest protein content was obtained from lipase AH (11.41%) before immobilization, while the highest levels of bound protein was observed from immobilized lipase AK (63.91%). Immobilized lipase AK had the highest interesterification activity (38.3% of total saturated fatty acid). Lipase AK was also used for a continuous reaction in which the slow flow of reactant resulted in increased reaction rate. Reusability of immobilized AK, AH and PS increased at the second reaction (120-196.5%). However, the activity of immobilized AK, which had the highest bound protein content (63.91%) decreased after the third reaction, while the activity of immobilized AH and PS was maintained until the sixth reaction.

• Journal of Practical Engineering Education
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• v.15 no.1
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• pp.209-221
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• 2023

In the external inspection and packaging stages of products used in the semiconductor manufacturing process, there is a problem in which particles are adsorbed to the product itself or a carrying tool due to electrostatic discharge. This study presents a methodology that can improve the problem of adsorption of particles to a product by using a practical TRIZ technique. By applying the proposed practical TRIZ-based methodology, the problem was defined, and contradictions caused by product waiting time were derived. Among the derived contradictions, physical contradictions were set and the concept of 'space separation' was applied to derive solutions such as 'installation of Ionizer' and 'improvement of the layout of the workroom'. As a result of the experiment by applying 'Ionizer Installation' and 'Workroom Layout Improvement' derived through the application of practical TRIZ, it was confirmed that the particle adsorption problem that occurs during the waiting time of the product can be solved.Through this study, it is expected that workers, facility engineers, and technical engineers working at manufacturing processes will be able to effectively solve the problems they face through creative thinking and change of ideas by using practical TRIZ techniques, and contribute to innovative technology development and productivity improvement.

• Applied Chemistry for Engineering
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• v.22 no.5
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• pp.532-539
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• 2011

The physical and chemical properties of the dried low rank coals (LRCs) before and after the surface treatment using ozone and ammonia were characterized in this study. The contents of moisture, volatiles, fixed carbon and ash consisting of dried LRCs before the surface treatment were about 2.0, 44.8, 44.9 and 8.9%, respectively. Also, it was composed of carbon of 62.66%, hydrogen of 4.33%, nitrogen of 0.94%, oxygen of 27.01% and sulfur of 0.09%. The dried LRCs was surface-treated with the various dry methods using gases such as ozone at room temperature, ammonia at $200^{\circ}C$ and then the dried LRCs before and after the surface treatment were characterized by the various analysis methods such as FT-IR, TGA, proximate and elemental analysis, caloric value, ignition test, adsorption of $H_2O$ and $NH_3-TPD$. As a result, the oxygen content increased and the calorific value, ignition temperature and the contents of carbon and hydrogen relatively decreased because the oxygen-contained functional groups were additionally generated by the surface oxidation with ozone which plays a role as an oxidant. Also, its $H_2O$ adsorption ability got higher because the hydrophilic oxygen-contained functional groups were additionally generated by the surface oxidation with ozone. On the other hand, it was confirmed that the dried LRCs after the surface treatment with $NH_3$ at $200^{\circ}C$ have the decreased oxygen content, but the increased calorific value, ignition temperature and contents of carbon and hydrogen because of the decomposition of oxygen-contained functional groups the on the surface. In addition, the $H_2O$ adsorption ability was lowered bucause the surface of the dried LRCs might be hydrophobicized by the loss of the hydrophilic oxygen-contained functional groups. It was concluded that the various physico-chemical properties of the dried LRCs can be changed by the surface treatment.

• Analytical Science and Technology
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• v.18 no.5
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• pp.436-443
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• 2005

A study of physical properties and their application using K-powdered activated carbon system followed powdered carbon dispersion was carried out at laboratory. scale. Two types of K-powdered activated carbon for the dispersion have been used in this study to investigate the catalytic removal efficiency of pollutants from the wastewater. From the surface properties obtained for carbon samples treated with aqueous solutions containing potassium salts, main investigations were subjected to isotherm shape, SEM, EDX and surface functional groups. K-powdered activated carbons were dispersed to wastewater with pH variation to investigate the removal efficiency for the color, COD, T-N and T-P. From these removal results of the piggery waste using K-powdered activated carbon, satisfactory removal performance in the region of pH 6~8 was achieved. The excellent effects for the dispersion of the K-powdered activated carbon were proved by the above mentioned properties of the material for adsorption and trapping of organics, and catalytic effects.

• Applied Chemistry for Engineering
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• v.2 no.3
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• pp.262-269
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• 1991

Bleaching effect of ozone on unsaturated coloring material was compared quantitatively with the change of composition of reactants through the ozone oxidation of ${\beta}$-carotene. Beeswax colorized by carotenoids was reacted with ozone in water, 0.5 % and 1.0 % sodium hydroxide solution, and 20 % and 95 % acetic acid solution and bleaching effect of each reaction condition was compared with each other. And then the additive effect of hydrogen peroxide was investigated. Decrease of unsaturated double bond of ${\beta}$-carotene was proportioned quantitatively to the bleaching effect of ozone on ${\beta}$-carotene and was in accordance with the bleaching effect on beeswax. The bleaching effect of ozone on coloring material in 1.0 % sodium hydroxide solution was better than any other condition and the absorbance of beeswax at 390 nm was improved to 0.045 with the addition of hydrogen peroxide(2 % of wax). For the bleaching of beeswax, it was concluded that the ozone oxidation was more effective than physical adsorption.

• Applied Chemistry for Engineering
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• v.29 no.3
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• pp.318-324
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• 2018

In this study, PAN (polyacrylonitrile) based activated carbon fibers were prepared by water vapor activation method which is a physical activation method. Activation was performed with temperature and time as parameters. When the activation temperature reached 700, 750 and $800^{\circ}C$, the activation was carried out under the condition of a water vapor flow rate of 200 ml/min. In order to analyze the pore structure of activated carbon fibers, the specific surface area ($S_{BET}$) was measured by the adsorption/desorption isotherm of nitrogen gas and AFM analysis was performed for the surface analysis. Tensile tests were also conducted to investigate the effect of the pore structure on mechanical properties of fibers. As a result, the $S_{BET}$ of fibers after the activation showed a value of $448{\sim}902m^2/g$, the tensile strength decreased 58.16~84.92% and the tensile modulus decreased to 69.81~83.89%.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.22 no.3
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• pp.119-125
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• 2016

Fresh-cut agricultural products provide convenience to consumers. However, quality changes or microbial growth can easily occur due to physical changes such as cutting and peeling etc. during processing. Therefore, efforts have been made to develop a functional packaging for extension of shelf life of fresh-cut agricultural products, food etc., and researches on prolongation of storage period have been actively developed. The shelf life is extended by antimicrobial, far infrared rays, air permeability, anti-fogging, weak current, ethylene gas adsorption or decomposition, gas composition changes such as MA (Modified Atmosphere) or CA (Controlled Atmosphere). The method of extending the shelf life by various complex factors. This paper based on the published literature to extend the shelf life of fresh-cut agricultural products, food etc., The paper has summarized the storage period extension packing method, packaging material for shelf life extension and comprehensive evaluation method.