• Journal of the Korean Graphic Arts Communication Society
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• v.26 no.1
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• pp.113-124
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• 2008

Viscosity of cellulose pulp was greatly decreased with endo-xylanase treatment but tiny decreased with exo-xylanase treatment. Change of freeness was greatly influenced with exo-xylanase treatment. The first stage of refining(5,000 revolution), freeness was greatly decreased with exo-xylanase treatment. After middle stage of refining(10,000 revolution) change of freeness was similar to endo-xylanase treatment. WRV(water retention value) was more effective exo-xylanas than endo-xylanase treatment. Interfiber bonding of cellulose fiber was disintegrated with exo-xylanse treatment.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.47 no.1
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• pp.35-44
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• 2015

Thermomechanical pulping process uses large amounts of energy, mostly electricity to run electrical facilities. Thermomechanical pulp (TMP) made from Pinus densiflora also has a big drawback that refining consumes 90 per cent of the total energy used in TMP process. This study explored to draw up a way to save refining energy through different thermal treatment at the stages of presteaming and refining. Presteaming temperature was $80^{\circ}C$, $100^{\circ}C$, and $120^{\circ}C$. After presteaming at each temperature, refining was carried out at $100^{\circ}C$, $120^{\circ}C$, and $140^{\circ}C$ respectively. In a presteaming stage, steaming temperature over $120^{\circ}C$ greatly contributed to the decrease of refining energy leading to earlier attainment of a target freeness, irrespective of refining temperature. In addition, NaOH treatment with presteaming enhanced better development of fiber properties during refining than presteaming without NaOH. High temperature refining at $140^{\circ}C$ produced a high strength paper, and wood chips treated by alkali responded better to refining than at over $120^{\circ}C$. Improved softening effect on wood chips led to the decrease in shives contents but it gave no effect on pitch contents of TMP.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.1
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• pp.96-100
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• 1993

The changes in the concentration of toropherol and carotenoid in pinenut oil at various stage of refining are studied during autoxidation. The oxidative stability of pinenut oil decreased with the refining degree increased. The tocopheol content of total crude oil was 55.51mg/100g oil and $\alpha$, ${\gamma}$and $\beta$-tocopherol in the crude oil were 25.48mg, 23.94mg and 6.99mg in order, respectively. The amount of $\delta$-tocopherol was trace. The concentrations of $\alpha$, ${\gamma}$ and $\beta$-tocopherol in pinenut oil after degumming or alkaline refining were 23. 85mg, 19.79mg and 6.12mg or 24.08mg, 24.04mg and 5.33mg, respectively. The content of f-carotene was 0.63% of total unsaponifiable materials and that of lycopene was trace. The concentrations of carotenoids and toropherols in pinenut oil decreased while autoxidation progressed. Degrees of destruction of carotenoids and toropherols. were significant at first stage of oxidation. Decrease in $\alpha$-toropherol was found to be faster than that in $\alpha$, ${\gamma}$-tocopherol during oxidation.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.42 no.4
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• pp.39-44
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• 2010

To increase the fracture toughness of paper made of Sw-BKP, refining and kneading conditions were analyzed. Curl and kink was known to increase the strain at break and the fracture touhness. Sequence of multiple stage beating, beating load and kneading were compared. When we applied a kneading treatment using a kneader at the final step, the most of the fiber transformation such as curl and kink occurred, the more the bulk and air-permeability improved. Physical strength and TEA(tensile energy absorption) were increased higher when kneading treatment before refining than only refining treatment was performed. TEA was increased because of higher elongation. It was found that the highest fracture toughness was obtained when applying the kneading treatment to the fibers in the pre-treatment step rather than in the middle step of beating or in the final step of beating.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2006.06a
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• pp.51-59
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• 2006

The surface of various mechanical pulp fibres including thermomechanical pulp (TMP), chemithermomechanical pulp (CTMP), and alkaline peroxide mechanical pulp (APMP) fibres, were characterized using SEM, AFM, and XPS. With SEM and AFM, middle lamella material was observed to be non-fibrillar, patch-like, while fibre secondary wall was observed to have a microfibrillar structure. It was found that after the first-stage refiner, lignin-rich middle lamella remainders are present on the fibre surface of all three pulps, although most of the fibre surfaces expose microfibrillar structure. After the final-stage refining, large amounts of granules are present on the TMP fibre surface. In contrast, most middle lamella remainders remain on the surface of CTMP fibres after final stage refining and even after peroxide bleaching. XPS results have confirmed that the non-fibrillar surface material is the lignin-rich middle lamella remainder., and the remainders of middle lamella contribute to the high surface lignin concentration.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.20 no.3
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• pp.147-155
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• 2010

This study was conducted to investigate the benzene exposure levels in coal chemical and petrochemical refining industries during BTX turnaround (TA) processes where benzene was being produced. Three companies producing benzene were selected, one coal chemical and two petrochemical industries. TA processes were classified into three stages: shut down, maintenance, and start up. Data was analyzed by classifying the refining method into 2 groups (Petrochemistry, Coal chemistry) for 823 workers. Comparing the data from petrochemical industries with data from a coal chemical refining industry, while benzene concentration levels of long-term samples during TA were not statistically different (p> 0.05), those levels of short-term samples were significantly different (p< 0.001). About 4.79 % of data in petrochemical industries exceed the occupational exposure limits (OELs) of benzene, 1 ppm. In a coal refining methods, about 15.7% exceeded the benzene OELs. The benzene concentrations in maintenance and start up stage of TA for petrochemical refineries were higher than those in a coal chemical refinery (p <0.01). These findings suggest that the coal chemical refining site requires more stringent work practice controls compare to petrochemical refining sites during TA processes. Personal protective equipments including organic respirators should be used by TA workers to protect them from benzene overexposure.

• Journal of Korea Foundry Society
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• v.18 no.5
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• pp.474-480
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• 1998

Microstructural characteristics of semi-solid state processed hypereutectic Al-Si alloys have been investigated. Main concern of the present study is to investigate the effects of P and Sr addition on the size and morphology change of the primary Si particles. Refinement of the primary Si particles was observed with the addition of P and Sr at the early stage of semi-solid state processing, but such a refining effects became negligible resulting in Si particles with a near-spherical morphology with continuous stirring. This implies that the microstructural transformation mechanism became more dependent to stirring effects than to the alloying effects during semi-solid state processing. Brittle fracture and agglomeration were proposed as the mechanisms for microstructural alterations during semi-solid state processing.

• International Journal of Advanced Culture Technology
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• v.12 no.2
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• pp.16-29
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• 2024

Mogao Grottoes in Dunhuang, China is one of the world cultural heritage, is the largest ancient grottoes art group in the world, and is a natural and cultural place with outstanding universal value for mankind all over the world. Dunhuang music and dance derived from the murals of Mogao Grottoes is an artistic representation of its thousand-year-old glorious history and an indispensable historical material for research. As one of the iconic images of Dunhuang music and dance, the "rebound lute behind the back" dance posture has unique charm value both in the original mural composition and the stage image. This paper analyzes the characters holding pipa in Dunhuang murals by case analysis, comparative research and other relevant research methods, then studies the stage image and posture of "rebound lute behind the back", and finally analyzes the stage works of "rebound lute behind the back". It is concluded that the dance image of "rebound lute behind the back" is a dynamic stage art work gradually formed by artists from the static Dunhuang murals through refining, developing, processing and transforming. This is to revive the image of Dunhuang music and dance murals, to provide reference and reference for the inheritance and development of Dunhuang culture, and then to enhance and enrich the artistic value of excellent traditional Chinese culture and world cultural heritage.

• Journal of the Korean Magnetic Resonance Society
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• v.18 no.1
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• pp.24-29
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• 2014

Atomistic molecular dynamics (MD) simulation has become mature enabling close approximation of the real behaviors of biomolecules. In biomolecular NMR field, atomistic MD simulation coupled with generalized implicit solvent model (GBIS) has contributed to improving the qualities of NMR structures in the refinement stage with experimental restraints. Here all-atom force fields play important roles in defining the optimal positions between atoms and angles, resulting in more precise and accurate structures. Despite successful applications in refining NMR structure, however, the research that has studied the influence of force fields in GBIS is limited. In this study, we compared the qualities of NMR structures of two model proteins, ubiquitin and GB1, under a series of AMBER force fields-ff99SB, ff99SB-ILDN, ff99SB-NMR, ff12SB, and ff13-with experimental restraints. The root mean square deviations of backbone atoms and packing scores that reflect the apparent structural qualities were almost indistinguishable except ff13. Qualitative comparison of parameters, however, indicates that ff99SB-ILDN is more recommendable, at least in the cases of ubiquitin and GB1.

• Korean Journal of Food Science and Technology
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• v.20 no.6
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• pp.868-872
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• 1988

The oxidation behaviour of Pinenut(Pinus Koraiensis S & Z) oil during storage were studied. And the oxidative stability of different oil samples by refining stage were also measured. The oil in whole pinenut or mashed pinenut was very stable during the storage at $35^{\circ}C$ for 10 weeks however, the oxidation rate was enhanced when pinenut oil was extracted and isolated from nut cake. On the other hand, crude oil was most stable and the highly purified pinenut oil was least stable, with other samples being intermediate in stability. The changes of fatty acid composition of various pinenut oil samples during storage were also discussed.