• Polymer(Korea)
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• v.34 no.3
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• pp.210-214
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• 2010

The structural development of triacetyl cellulose (TAC) was studied as a function of solution casting processing parameters such as dope concentration, evaporation temperature, annealing temperature and the addition of plasticizer. The crystalline structure was developed by the solution casting and the level of crystallinity was increased with increasing dope concentration and evaporation temperature. The crystalline structure could be enhanced by the annealing process after formation of TAC film. Introducing plasticizer resulted in decreasing melting temperature and crytallinity of TAC film due to the increase of chain mobility. It was also found that thermal stability of TAC was improved due to the rigid structure of applied plasticizer.

• Journal of the Korea institute for structural maintenance and inspection
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• v.21 no.6
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• pp.169-177
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• 2017

Recently, as the size of transportation vessels has increased, there is a growing need for securing the front-water depths of existing port facilities. The method of deepening front-water depth is securing the depth of the port facility, and it is reinforced by grouting after excavating the rubble-mound to the required depth. The purpose of this study is to investigate the reinforcing performance and filling performance of thixotropic grout as a grouting material for reinforcing rubble-mound. Compressive strength tests were carried out for two types of thixotropic grout, and 5 specimens with a diameter of 400 mm and a height of 530 mm were manufactured and evaluated for filling performance. The required strength of reinforced rubble-mound required to ensure the safety of the structure is 6 MPa. All the thixotropic grouts used in this study were found to satisfy the required strength over 9 MPa at 7 days of age. As a result of visual observation of filling state of the filling performance test specimens, it was confirmed that the thixotropic grout was well filled up to the desired fillet height.

• Applied Chemistry for Engineering
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• v.3 no.2
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• pp.341-348
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• 1992

PVC was compounded with various crosslinking agents, plasticizers and acrylonitrile butadiene rubber(NBR) to evaluate their effects on the radiation gel percent, elongation at break, heat distortion and heat shrinkage. Gel yield of PVC increased with increasing unsaturation levels per molecular weight of crosslinking agents while PVC containing NBR was more sensitive to crosslinking than PVC itself regardless of the types of crosslinking agents and plasticizers. It was found that gel percent was increased with increasing radiation dose, while heat distortion was decreased with increasing gel percent. Heat shrinkage was increased with decreasing stretching temperature and increasing annealing temperature.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.40 no.3
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• pp.53-58
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• 2008

Wood composite, could generally be made from very fine wood powder(<150 mesh) because more large size of wood particle had much less plasticity compared of polymer. To make more high plasticity of relatively large size of wood particle, wood particles were chemically modified with some reagent for acetylation and esterification, etc. WPC(wood plastic composite) was prepared with chemically modified wood particles and the mechanical properties of WPC were evaluated. WPC of esterified wood with maleic anhydride shows the highest level in tensile strength and breaking elongation.

• Journal of the Korea Furniture Society
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• v.11 no.2
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• pp.55-60
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• 2000

Liquid ammonia treatment known as the most effective Wood plasticization method, was applied to two typical domestic species, Pinus densiflora, Castanea crenata. Small specimens of 30mm width, 300mm length and two thicknesses, 5 or 10mm, were used. For 5mm thick Specimens, Pinus densiflora was quite well plasticized iker 4 hour liquid ammonia treatment, while Castanea crenata was not plasticized even after 4 hour treatment. Specimens of 10mm thick Pinus densiflora were hardly plasticized, but those with kerfs were bent somewhat easily, With the increase of liquid ammonia treatment time the thermal conductivity of Pinus densiflora increased, while that of Castanea crenata didn't Presteaming before liquid ammonia treatment didn't improve the plasticization of both species.

• Proceedings of the Korean Fiber Society Conference
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• 2001.10a
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• pp.9-12
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• 2001

Blending is an easy and popular means to achieve a desired set of characteristic properties. The blends, by melt mixing of thermoplastic materials and elastomer, have received considerable attention in recent years. It is well known that nearly all blends comprise one polymer domain dispersed in the matrices of the other polymer [1]. (omitted)

• Proceedings of the Plant Resources Society of Korea Conference
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• 2003.04a
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• pp.71-73
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• 2003

동물성 단백질 사료를 섭취함으로써 발생되기 쉬운 광우병등을 예방하고 단경기 사초용작물로서 조숙성이고 직립형이어서 이용하기가 편리하고 건물수량은 높아서 조사료로서 사료가치가 우수한 잠재력을 갖춘 사초용 유채의 주변 생산성을 높이고자 춘파용 다수성 품종으로 선발된 Velox를 공시하여 춘파성 검정시험을 실시하였던바 그 결과는 다음과 같다. 1. 초장, 분지수, 엽수등의 수량구성형질은 3월중하순에 파종한구가 가장 우수하였다. 2, 생초수량과 건물수량도 역시 3월중 하순에 파종한 구가 증수되었다. 3. 조단백질 함량은 파종기가 늦어질수록 높았고, NDF, ADF, cellulose 및 lignin등의 조섬유 함량은 파종기가 늦어질수록 저하되었다. 4. IVDMD은 일정한 경향을 발견할 수 없었고 건물수량이나 가소화 건물 수량은 3월중ㆍ하순에 파종한 구가 높았다.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2003.04a
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• pp.83-86
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• 2003

최근 단경기 사료작물로 사초용 유채가 관심을 끌게 되어서(김등, 1986; 안등, 1989 ; 조등, 1988). 사초용 유채의 재배 면적 확대가 바람직할 것으로 사료되어 춘파성 시비량 구명시험을 실시하여 3요소 시비수준이 사초용 유채의 생육특성과 건물수량 및 사료가치에 미치는 영향을 구명코자 3월25일에 파종하여 수행하였던바 그 결과는 다음과 같다. 1. 시비량에 있어서는 3요소중 질소의 비효가 가장 컸으며, 인산과 가리는 증비(기준량 6kg/10a초과)의 효과가 거의 없었다. 2. 질소의 시용은 16kg/10a까지 직선적인 증수를 나타냈다. 3. 3요소의 적정 시비 수준은 N-P$_2$O$_{5}$-K$_2$O = 16-6-6 kg/10a 로서 조단백질 함량이 가장 높고 NDF, ADF, Cellulose 및 Lignin 등 조섬유 함량이 가장 낮으며, IVDMD 가 높고 건물수량이나 가소화 건물 수량이 가장 높아서 유의차가 인정 되었다 ( P 〈0.05 ).

• Applied Chemistry for Engineering
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• v.7 no.6
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• pp.1087-1095
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• 1996

Pervaporation experiments of ternary ethanol/isopropanol/water mixtures were performed using poly(dimethyl siloxane)(PDMS) membrane at $45^{\circ}C$ and the mutual effects of ethanol and isopropanol on the permeation characteristics were studied. Compared to the case of the binary aqueous ethanol or isopropanol solutions, the existence of ethanol or isopropanol in the ternary mixtures resulted in the depression of each other's permeation rate. The depression effect of ethanol on the isopropanol permeation was more considerable than the depression effect of isopropanol on the ethanol permeation. These decreases in the permeation rate were thought to be due to the larger interactions between permeants than the plasticizing effects of ethanol or isopropanol on the polymer membrane. The strong interactions between permeants reduced the driving forces for both ethanol and isopropanol permeation in the ternary mixtures.

• Journal of Animal Science and Technology
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• v.45 no.6
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• pp.949-956
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• 2003

For the Exp. 1, a total of sixty pigs(15.95${\pm}$0.09kg average initial body weight) were used in a 28-d growth assay to determine the effects of extruded chinese corn on growth performance and nutrient digestibility in nursery pigs. Dietary treatments included 1) UCORN(U.S. corn-SBM based diet), 2) CCORN(Chinese corn-SBM based diet) and 3) ECCORN(Extruded Chinese corn-SBM based diet). Overall period, average daily gain of pigs fed ECCORN diet was higher than that of pigs fed CCORN diet(547 vs 522 g/d), however, there was not significant difference. On day 10 of the experiment, pigs fed UCORN and ECCORN diet had significantly increased in DM and DE digestibilities compared to pigs fed CCORN diet(P〈0.05). Also, on day 24 of the experiment, pigs fed UCORN and ECCORN diet had a significant increase in DM digestibility compared to pigs fed CCORN diet(P〈0.05). Pigs fed ECCORN diet had significantly increased DE digestibility compared to pigs fed CCORN diet(P〈0.05). For the Exp. 2, three cannulated barrows(54.09kg average initial body weight) were used to determine the apparent ileal digestibilities of amino acids and nutrient digestibility of extruded corn in finishing pigs. Dietary treatments were the same as in Exp. 1. Apparent ileal digestibility of cystine was greater for UCORN and ECCORN than for CCORN(P〈0.05). Apparent digestibility of DM at the total tract was greater for UCORN and ECCORN than for CCORN(P〈0.05). Pigs fed UCORN and ECCORN diet had a significant increase in apparent total tract digestibility of N compared to pigs fed CCORN diet(P〈0.05). In conclusion, the results obtained from these feeding trials suggest that the extruded corn for nursery pigs had affected growth performance and DM and DE digestibilities. In finishing pigs, extruded corn was an effective means to improve apparent total tract digestibilities of DM and N.