• Fiber Technology and Industry
• /
• v.5 no.3_4
• /
• pp.128-135
• /
• 2001

• Journal of the Korean Geosynthetics Society
• /
• v.10 no.3
• /
• pp.1-8
• /
• 2011

This paper presents the performance evaluation of asphalt pavement reinforced with fiber sheet type of geosynthetics and observations conducted to evaluate the practical efficiencies and performance of overlay asphalt pavement reinforced with geosynthetics. In this study, performance evaluation were performed for the six section of construction site. The performance indcators of asphalt pavement reinforced with geosynthetics has been collected Automatic Road Analyzer (ARAN), Falling Weight Deflectometer (FWD) and have been analyzed for rutting, cracking ratio, falling weight and international roughness index. As a result of performance evaluations, geosynthetics reinforced asphalt pavement is sigficant effect on increasing a cracking resistance than the non-reinfroced asphalt pavement, also rutting and crak is slowly increase as incerasingly performance period.

• Polymer(Korea)
• /
• v.26 no.3
• /
• pp.389-399
• /
• 2002

Poly (ethylene terephthalate) (PET) fibers were modified by deep UV irradiation which was produced by a low pressure mercury lamp. FT-IR and XPS analyses were used to elucidate the surface chemical composition of PET fibers treated with UV. Relative $O_{1s}$ intensity increased considerably and it was found that oxygen was incorporated in the form of COO on the fiber surface. FT-IR and XPS analyses proved the existence of carboxylic groups on the surfaces and the adsorption test of cationic compound further supported these results. The concentration of carboxylic acid group on the surface increased remarkably with Increasing irradiation time. XPS analysis and adsorption experiments proved that the surface structure of the UV-irradiated PET fibers were stable for 12 months. Antibacterial property and the deodorization rate of UV-irradiated PET fibers adsorbed with the berberine compound were investigated. Reduction rates of bacteria increased by about 21 to 99% compared to unradiated PET fiber. Deodorization rates of 23% for unradiated PET fiber increased to about 75% for 30 min irradiated samples.s.

• Proceedings of the Korean Society of Dyers and Finishers Conference
• /
• 2011.11a
• /
• pp.8-8
• /
• 2011

Environmental technology (ET)는 이미 세계적으로 가장 중요한 기술로 주목받고 있으며 친환경적이고 생체적합한 상품에 대한 수요가 계속해서 증가하고 있다. 섬유시장에서도, 항균성, 피부노화 방지, 아토피 방지, 보습제와 같이 수많은 다기능성 친환경 제품들이 계속해서 개발되고 소개되어지고 있다. 특히, 피부 보호를 위한 생체적합 보습 가공제로 쓰이는 squalene, collage, chitosan, hyaluronic acid과 같은 물질들은 cosmetics, medical 시장에서 널리 쓰이고 있다. 그러나 섬유시장에서의 이러한 물질들은 섬유에 적용시켰을 때 만족스럽지 못한 기능으로 인해 그리 좋지 않은 평가를 받고 있다. 천연소재를 이용해 스킨케어 제품 제조 시 지속적인 안정성의 문제와 제품의 기능성, 내구성이 만족스럽지 못한 결과를 보인다. 이러한 문제를 해결하고자 binder처리를 시도하였지만 가공제의 스스로의 기능이 현저하게 저하되는 문제로 인해 널리 쓰이진 않았다. 또한 안정성을 증진시키고자 마이크로캡슐을 개발하였지만 섬유의 터치감이 거칠어지고 가격적인 면에서 만족스럽지 못한 문제점이 있다. 본 연구에서는 새로운 phospholipid 화합물 2-methacryloyl oxyethyl phosphoryl choline (MPCE)를 이용하여 polyester에 적용시킨 후 다양한 조건들을 살펴보았다. MPCE처리가 된 섬유는 흡습성, 대전방지성, 항균성, 피부자극이 없는 것과 같은 생체적합한 기능을 보여주었다.

• Proceedings of the KAIS Fall Conference
• /
• 2010.05b
• /
• pp.855-858
• /
• 2010

이 연구의 목적은 흰쥐의 궁둥신경의 손상을 준 뒤 달리기운동을 시켜 운동이 근육재생에 효과가 있는지를 밝힐 목적으로 시행하였다. 수컷 Sprague-Dawley계 흰쥐의 궁둥신경을 압궤손상을 준후, 하루 60분 씩 주 5회 운동을 시켰다. 궁둥신경 압궤손상 후 12일(5일간 운동), 19일(10일간 운동), 26일(15일간 운동), 33일(20일간 운동 및 61일(40일간 운동)에 흰쥐를 희생시켜 장딴지근육을 절취하여 냉동절편을 만들었으며 중간세사인 desmin과 vimentin에 대한 면역조직화학적 염색방법을 시행하였고 NADH-TR을 이용한 효소조직화학적 방법으로 뼈대근육의 변성 등을 관찰하였다. 중간세사단백 중 desmin은 근육섬유의 변성 및 재생과정 모두에서 발현되며 vimentin은 재생과정에서만 발현되었다. 대조군보다 실험군에서 desmin과 vimentin의 면역 반응성이 높았고, 실험군의 근육섬유들은 손상 후 61일째에 횡단면에서 각을 갖고 있어 정상 근육섬유임을 입증해 주었으나 대조군의 근육섬유는 정상으로 회복되지 않은 둥근 근육섬유가 관찰되었다. 19일째의 NADH-TR반응에서 대조군에서는 근육 섬유형 군집(fiber type grouping)으로 인해 diformazan 과립이 뭉쳐져 있음을 볼 수 있으나 실험군에서는 점점 diformazan 과립이 고르게 분포됨을 볼 수 있었다. 재신경지배가 일어 날 때 나타나는 표적근육섬유(target fiber)는 NADH-TR반응에서 26일 실험군의 일부 근육섬유에서 처음으로 관찰되었다. 61일째 NADH-TR반응에서 대조군은 아직도 diformazan 과립이 근육섬유성 군집을 보였으나 실험군에서는 정상군과 다름없는 염색성이 관찰되었다. 이상의 결과로 흰쥐 궁둥신경 압궤손상 후 트레드밀 달리기 운동이 흰쥐 다리 뼈대근육의 중간세사발현에 효과가 있다고 생각된다.

• Composites Research
• /
• v.19 no.3
• /
• pp.15-22
• /
• 2006

In this study, we prepared glass fiber reinforced polypropylene composites using Brabender twin-screw extruder. Compatibilizer, polypropylene-based maleic anhydride (PP-g-MAH), was used to increase the molecular interaction between polypropylene matrix and glass fiber and to enhance melt processability. We also measured the shear and uniaxial elongational behaviors of glass-fiber reinforced composites in the absence or presence of compatibilizer. The effects of compatibilizer and fiber loading on the viscoelastic behaviors were examined. It was fuund that the PP-g-MAH compatibilizer improved the fluidity and increased the molecular bonding of composite melts in shear flow. Transient elongational viscosity was increased with fiber loadings in uniaxial elongational flow However, it was decreased with increasing elongational rates because of microscale shear flow between fibers.

• Tuberculosis and Respiratory Diseases
• /
• v.49 no.4
• /
• pp.441-452
• /
• 2000

Background : It is well known that the prevalence of lung cancer is higher in idiopathic pulmonary fibrosis (IPF) patients than in the general population. This high prevalence is explained by the concept of 'scar carcinoma'. There have been several reports on the prevalence of histologic typo of lung cancer in IPF with conflicting results. Despite of the high smoker rate in almost all previous reports, none considered the smoking history of patients. Therefore we performed a separate studies on fibrosis associated lung cancer and smoking associated lung cancer. The purpose of this study is to investigate the proportion of lung cancer in IPF that is fibrosis associated and to determine the most common histologic type in fibrosis associated lung cancer in IPF. Method : A retrospective review of medical records and radiologic studies was performed for cases of lung cancer with IPF. We investigated smoking history, sequence of diagnosis of lung cancer and IPF, histologic type of lung cancer and the cancer location, especially whether the location is associated with fibrosis. To evaluate the proportion of fibrous associated lung cancer, the lung cancer in IPF were categorized according to the presence of fibrosis at cancer location. Results : Fifty seven patients were subjects for this analysis. Six (11%) cases were diagnosed as lung cancer during follow-up for IPF, and both diseases were diagnosed simultaneously in the others. Ninety four percent of patients were smokers and the average smoking amount was 47.1$\pm$21.9 pack-year. Among the patients with IPF and lung cancer, 42(80.8%) cases were considered as "fibrosis associated". The remainder was "not fibrosis associated" and probably was due to smoking etc. Although the most frequent histologic type was squamous cell carcinoma as a whole, adenocarcinoma was the prominent histologic type in "fibrosis associated lung cancer." Conclusion : Considering the proportion of "fibrosis not associated lung cancer" in the patients with IPF and lung cancer, significant proportion of lung cancer in IPF may not be fibrosis induced. This may influence the distribution of histologic type of lung cancer in IPF.

• Korean journal of food and cookery science
• /
• v.11 no.1
• /
• pp.20-25
• /
• 1995

The effects of cooking on the dietary fiber content in rice, brown rice, yellow soybean and black soybean were investigated. The dietary fiber contents were analyzed by Prosky's method(AOAC method) after boiling, microwave heating and autoclaving of the sample. It was showed that the different cooking methods resulted in different effects on the insoluble dietary fiber contents. Except yellow soybean, cooking time had little effect on insoluble dietary fiber contets in the other samples. The contents of soluble dietary fiber were generally increased by cooking. Increased cooking time reduced the content of soluble dietary fiber in brown rice but increased in rice. However, no significant differences caused by cooking time were observed for soluble dietary fiber in black soybean. The effects of cooking method on the total dietary fiber contents were similar to those of insoluble dietary fiber. The reasons for this might be that the main fraction of total dietary fiber was insoluble forms and the content of total dietary fiber was calculated as the sum of insoluble and soluble dietary fiber content.

• Journal of the Korea institute for structural maintenance and inspection
• /
• v.22 no.6
• /
• pp.157-163
• /
• 2018

This study is aimed at controlling the fiber orientation and improve the fiber distribution in fiber-reinforced cement composites using blades that can be placed inside the existing nozzles. To optimize the blade parameters, multi-physics finite element analysis was performed that could account for the flow of the cementitious matrix material, the movement of the entrained fibers, and the interactions with the nozzle. As a result, this study defined the blade distance, length, and position as a function of the fiber length to be used in the field. The blades with a distance from 1.2 to 2.4 times the fiber length and length from 4 to 8 times the fiber length, as well as located at below 14 times the fzfiber length from the nozzle exit maintained the fiber orientation angle less than $5^{\circ}$. In addition, the blade-type nozzle proposed in the study can be attachable and detachable to the conventional casting equipment, and thus it can provide the usability and convenience in practical applications.

• Composites Research
• /
• v.35 no.6
• /
• pp.456-462
• /
• 2022

Since natural fibers are highly flammable, it is not easy to make them flame retardant. In this study, a liquid flame retardant based on phytic acid, APTES, and Thiourea, which are flame retardant candidates derived from nature, was prepared and its performance was verified through flame retardant treatment and flame retardancy evaluation of bamboo fibers. When a liquid flame retardant is used, it is possible to treat a large amount of natural fibers with flame retardant treatment. Nine types of flame-retardant treated bamboo fibers were prepared according to the Taguchi design of experiment method. Thereafter, vertical burning test and microcalorimeter test were performed for flame retardancy evaluation, and the surface of natural fibers before and after flame-retardant treatment was compared using scanning electron microscope. The results show that phytic acid has a significant effect on improving the flame retardancy of natural fibers. Through microstructure analysis, it was assumed that the phytic acid helps flame retardant to uniformly adhere to the surface of natural fibers. If such research results are utilized, it is possible to make a large amount of natural fibers high flammability in an eco-friendly way, which is expected to be advantageous for the application of prototypes.