• Polymer(Korea)
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• v.29 no.6
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• pp.565-570
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• 2005

Melt processing characteristics of nylon 6 (N6) has been investigated by controlling the melt viscosity in melt impregnation process. Calcium stearate (CaST) was introduced as a lubricant for N6 and the melt viscosity of N6 decreased with adding only 1 wt$\%$ of CaST. In addition, reactive blending with polycaprolactone (PCL) was carried out by lowering the melt viscosity in N6. It was found that the melt viscosity of N6 could be controlled and further melt viscosity drop could be obtained by applying phenyl phosphite (PP) and diphenyl phosphite (DPP) to enhance the transesterification between N6 and PCL. Our approaches show that the melt viscosity of N6 could be reduced without loss of thermal stability which is the critical problem in high temperature melt impregnation process of N6.

• Asian-Australasian Journal of Animal Sciences
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• v.10 no.2
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• pp.210-214
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• 1997

Ruminal degradation characteristics and intestinal availability of crude protein (CP) in four animal-origin feeds (fish meal, meat meal, viscera meal, feather meal) were estimated by mobile nylon bag technique. Three ruminally and duodenally cannulated Holstein dairy cows (average body wt. 550kg) fed a diet containing 40% concentrate and 60% orchard grass hay on a dry matter (DM) basis. Assuming that the outflow rate of diet in rumen is 5% per hour (k =0.05), contents of quickly degradable CP (QDP), slowly degradable CP (SDP), and undegradable CP (UDP) in the rumen were 27.6%, 9.4%, 63.0% for fish meal, 34.3% 28.1%, 37,6% for meat meal, 43.9%, 12.5%, 43.6% for viscera meal, and 14.4%, 15.8%, 69.8% for feather meal, respectively. Intestinal CP degradability was 51.0% for fish meal, 27.2% for meat meal, 37.9% for viscera meal and 56.2% for feather meal. Available UDP in the intestinal tract was contained 288 g, 217 g, 246 g and 423 g per kilogram DM of diet in fish meal, meat meal, viscera meal and feather meal, respectively.

• Korean journal of food and cookery science
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• v.19 no.4
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• pp.439-446
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• 2003

This study was performed to investigate the change in the chemical components of red pepper powder using different packaging materials and various storage conditions. Red pepper powders with 11 and 15% initial moisture content were packed with five different materials and stored at different temperatures (0, 20, and 30 C) for a one year period. Over the storage period, each combination was periodically sampled, and examined for composition changes. The five packaging materials were: linear low density polyethylene(LLDPE), nylon/LLDPE(Ny/LLDPE), saran coated ethylene vinyl acetate copolymer/linear low density polyethylene(B650), nylon/Tie/nylon/ethylene-vinyl alcohol copolymer/nylon/Tie/LLDPE(RDX-2787) and oriented polypropylene/alumimum/LLDPE(OPP/Al/LLDPE), and the three storage conditions were (28.3${\pm}$1.0)$^{\circ}C$ with (15.5${\pm}$2.8)% relative humidity, (18.6${\pm}$0.5)$^{\circ}C$ with (46.6${\pm}$4.9)% RH, and (0${\pm}$2)$^{\circ}C$ with (80${\pm}$10)% RH, respectively. The moisture contents of all samples changed according to the relative storage humidity, except those of the samples packed with OPP/Al/LLDPE, which remained constant throughout the storage period. The capsaicinoids content of the red pepper powder did not change significantly for 6 months, but gradually decreased after that until about 85% of the original amount remained at the final stage of storage. The ASTA color values of all samples decreased gradually throughout the storage period. The higher the storage temperature, the more severe the deterioration. The color deterioration seemed greatly related to the existence of oxygen, as the deterioration was especially severe in the samples packed with LLDPE and B650, where the oxygen transmission rate were highest among the five packaging materials.

• Journal of Korean Society for Atmospheric Environment
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• v.18 no.4
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• pp.297-303
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• 2002

Fine particles (d$_{p}$ < 2.5 $\mu$m) were measured using an annular denuder system (ADS) in Chongju. The data set was collected on fifty-eight different days with a 24-hr sampling period from October 27, 1995 through August 25, 1996. Particulate nitrate in the ADS was also measured on teflon and nylon filters in series behind denuders to collect HNO$_3$, HNO$_2$, SO$_2$and NH$_3$. From this study. the mean concentration of particulate nitrate of PM$_{2.5}$ in the ADS were seen with the following order: winter (5.05) ＞fall (4.36) ＞spring (3.92) > summer (1.10 $\mu\textrm{g}$/㎥). Nitrate losses, which calculated from the ratio of nylon filter nitrate to the sum of teflon and nylon filter nitrates, varied in the following manner summer (72.2%) > spring (42.6%) > fall (23.5%)> winter (0.4%). Especially, gaseous nitric acid was dominant at temperature higher than 8$^{\circ}C$ while particulate nitrate was major species in total nitrate below that temperature. This indicates the particulate nitrate loss is strongly correlated rather with ambient temperature.e.e.

• Asian-Australasian Journal of Animal Sciences
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• v.6 no.2
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• pp.197-203
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• 1993

The protection of dry matter and nitrogen from rumen degradation of dhaincha seed (Sesbania aculeate) meal was studied using nylon bag technique. The dhaincha seed meal was subjected to various heat treatments that included oven drying, autoclaving and boiling. Similar experiment was conducted with fish meal as reference for comparison. The oven-dried dhaincha meal was found to retain more dry matter and nitrogen than was found boiled or autoclaved meal. While autoclaving appeared to improve nitrogen and dry matter retention to some extent, boiling seemed to cause more loss of dry matter from nylon bag. Heat treatment caused high retention of nitrogen by fish meal. The calculated effective protein degradation was 80.4% and 83.2% for the oven dried fish meal and dhaincha seed meal whereas same values were 74.2% and 86.7% for autoclaved fish and dhaincha seed meal respectively at the outflow rate of 4.4% per hour. The in vitro study revealed higher digestibility for heat treated samples by pepsin. The dry matter, nitrogen and ash content of dhaincha seed meal were 85.93%, 5.93% and 7.31% respectively.

• Journal of the Korean Applied Science and Technology
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• v.12 no.2
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• pp.13-19
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• 1995

Spin finish(SF) for nylon filament was prepared. The influence on the properties of filament obtained by treating the prepared spin finish in this study(SF-2) and foreign-made spin finish(Spinnar N-100) was compared. SF-2 prepared by blending of spindle oil 70g, paraffin wax 10g, glyceryl mono-oleate 5g, POE(6) nonylphenyl ether 4g, POE(10) nonylphenyl ether 4g, POE(10) octylphenyl ether 2g, POE(14) mono-oleate 4g and water 1g was excellent in its characteristics. Some of the properties of Nylon filament treated with SF-2 were better than those treated with Spinnar N-100. Also, optimal physical conditions of nylon filament according to the number of revolution of oil roller were obtained at conditions of 5rpm of number of revolution oil roller, 1.25% of SF-2 oil pick up, and denier 69D.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.29 no.3
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• pp.191-199
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• 1993

In order to analysis creep characteristics and elastic recovery of the high-tech fibers for fishing gear materials, creep and elasticity tests were carried out on netting twines made of nylon, kevlar 29 and techmilon respectively. After creep tests, the rupture surface of raw materials was observed by scanning electron microscope(SEM). The results obtained are as follows: 1. Netting twines were arranged in order of creep rupture time as follow: techmilon, kevlar 29, nylon. The creep progressive pace was the fastest in techmilon. 2. In order of the creep elongating, netting twines were arranged as follows: nylon, techmilon, kevlar 29. 3. The rupture time T sub(r) decreased almost linearly with the increase of applied load L on the log-log scaled graph. The empirical equations computed for kevlar 29 and techmilon are as follows: T sub(r kevlar 29)=1.9512$\times$1037L super(-15.773). T sub(r techmilon)=2.7146$\times$1016L super(-6.831). 4. It was observed by SEM that creep was progressed in all netting twines. The difference of rupture morphology was recognized clearly in tensile and creep tests. 5. In order of the elastic recovery, netting twines were arranged as follows: techmilon, kevlar 29, nylon.

• Journal of the Korean Society of Clothing and Textiles
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• v.28 no.6
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• pp.819-829
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• 2004

This study was carried out to suggest a new swimsuit fabric with improved durability, comfort and appearance, by employing PTT(polytrimethylene terephthalate). Objective and subjective performances of newly woven PTT/PU (polyurethane) blend fabric were estimated and compared with nylon/PU(80/20) which is currently used for swimsuit. According to the questionnaire, the most serious problems of swimsuit fabrics were such that they were easily degraded by chlorinated water and this made fabric inelastic and transparent. After exposure to the chlorinated water, PTT blend fabrics showed higher retention of breaking strength, bursting strength, elastic recovery and crystallinity. suggesting that PTT/PU(87/13) was the most excellent material in durability. PTT blend fabrics absorbed less water and dried faster than nylon/PU and thus PTT/PU(87/13) was shown to be the best in respect of comfort. All of the specimens used in this study exhibited satisfactory colorfastness to sea water, chlorinated water and light except that nylon/PU(80/20) represented weak colorfastness to chlorinated water. From the subjective wearing sensation test, PTT/PU(82/18) was shown to posess the best wearing sensation. From the overall evaluation or objective and subjective properties, PTT blend fabrics exhibited superior performances to nylon/PU(80/20), suggesting that they can be successfully used as a new durable and comfortable swimsuit fabric.

• Fibers and Polymers
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• v.6 no.1
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• pp.35-41
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• 2005

Research and development of nano fiber products is very active over the world. Physical characteristics and dyeing properties of nylon 66 nano fiber were investigated in this study. X-ray diffraction, DSC, analysis of amino end group, and water absorption were performed to get information concerning physical properties of nano fiber. Nylon 66 nano fiber was dyed with high molecular mass acid dyes. Effects of dyeing temperature, pH of dyeing solution, and concentration of acid dyes on dyeing properties such as rate of dyeing and the extent of exhaustion, were examined and compared to those of regu­lar fiber. It was found that nano fiber adsorbed acid dyes at lower temperature, got rapidly dyed, and its extents of exhaustion at specific dyeing temperature were higher than regular fiber. It was also observed that nano fiber could adsorb a large amount of acid dye without a significant loss in the extent of exhaustion. Washing fastness of the dyed nano fiber was lower by $1/2\~1$ grade, light fastness by 1 grade than the dyed regular fiber.

• The Korean Journal of Rheology
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• v.8 no.2
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• pp.69-77
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• 1996

장섬유강화 열가소성 고분자 복합재료 (FRTP)의 난연성과 개선을 위하여 polyhenylene sulfide(PPS)를 첨가한 polyamide 6(PA6)/glass fiber (GF)의 FRTR를 제조하 였다. 고점성수지내에 보강섬유를 균일하게 분산시키고 함침성을 높임과 동시에 보강섬유의 손상을 방지하기 위하여 섬유상 수지와 보강섬유를 분섬비동장치에서 직접혼방시키고 이를 압축성형하는 독특한 공정을 도입하였다. 제조된 복합재료의 유변학적 특성 형태학적특성 인장 및 충격특성 열적특성, 난연성, 내약품성에 관한연구를 수행한 결과 복합재료와 기계적 특성을 약화시키지 않으면서도 난연성가 내약품성을 현격히 향상시킬수 있는 FRTP의 제조 가 가능함을 확인하였다.