• Korean Chemical Engineering Research
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• 제48권1호
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• pp.121-127
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• 2010

본 연구의 목적은 효소법을 이용한 바이오디젤의 생산에서의 효소(lipase) 활성화를 최적화함에 있다. 효과적인 방법으로 효소를 고정하기 위해 방사선 그라프트 중합법을 이용한 부직포에 음이온 교환기인 ethanolamine과 diethylamine을 도입시켜 음이온 교환 부직포(이때 얻어진 부직포는 EtA, DEA-EtA 부직포라 함)를 합성하였다. 기존에 사용하던 다공성 중공사막의 경우 시간이 지남에 따라 막힘 현상에 따라 유속이 현저하게 줄어드는 점을 보완하고자 기공(pore size)이 $300{\mu}m$인 부직포를 선택하였다. 이 부직포에 음이온 교환기가 도입된 EtA, DEA-EtA 부직포의 최적효소 흡착 특성과 효소 활성도에 대하여 고찰하였다. 그 결과 효소 흡착량은 EtA, DEA-EtA 부직포가 비슷하였으나(EtA non-woven fabric: 15.69 mg/g, DEA-EtA non-woven fabric: 14.45 mg/g) 기름을 투과시킨 결과 효소 활성화는 DEA-EtA 부직포가 EtA 부직포에 비해 현저히 떨어짐(EtA non-woven fabric: $3.50mol/h{\cdot}kg$, DEA-EtA non-woven fabric: $0.38mol/h{\cdot}kg$)을 알 수 있었다. 이 음이온교환기를 이용해 효율적인 바이오디젤 생산을 위한 온도, 효소고정량, 기름과 알코올과의 관계 등의 최적의 조건을 도출하였다.

• 한국생산제조학회지
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• 제6권4호
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• pp.96-100
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• 1997

Tensile properties of carbon fiber reinforce composite laminates with non-woven carbon mat are evaluated in this paper. Composite laminates are made by inserting non-wovon carbon mat between layers, The specimens were cut and polished according to ASTM standard . Longitudinal and Transverse Young's modulus are obtained by tensile test. Young's moduli without non-woven carbon mat are compared with those with non-woven carbon mat. Longitudinal and Transverse tensile strength are also investigated. Experimental results show that the transverse Young's modulus of composite materials with non-woven carbon mat is about 10% higher than that of composite materials without non-woven carbon mat. Longitudinal tensile strength of composite materials with non-woven carbon mat is about 24% higher than that of composite materials without non-woven carbon mat. Transverse tensile strength and torughness also increase by inserting non-woven carbon mat between layers.

• 한국의류산업학회지
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• 제16권2호
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• pp.319-325
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• 2014

This article describes a method for producing chitosan non-woven fabrics by just hot pressing without the use of a binder. A study has been made of the wet spinning of chitosan fiber. The fibers were rinsed thoroughly in running water and chopped wet into staples of with a length of approximately 5-10 mm. The chopped chitosan staples were dispersed uniformly in water and fabricated using a non-woven making machine. This study examined the formation and the characteristics of chitosan non-woven fabrics manufactured by hot pressing without the use of a binder. The effects of the non-woven fabrication conditions on the thermal, morphological, structural, and physical properties of chitosan non-woven fabric with and without water as a plasticizer were studied. The temperature of the exothermic peak, decomposition of chitosan fibers increased with increasing heating rate. Water in the chitosan fiber effectively plasticized the chitosan fiber. The thermal bonded structure of the wet chitosan fiber with water as a plasticizer was clearly found in many parts of the non-woven fabric at a fabrication temperature of $200^{\circ}C$. The intensity and profile of the (100) plane($2{\theta}=10.2^{\circ}$) and (040) plane($2{\theta}=20.9^{\circ}$) in the chitosan non-woven fabric decreases and became smooth in the non-woven fabric formation by melting.

• International Journal of Industrial Entomology and Biomaterials
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• 제44권1호
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• pp.12-20
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• 2022

In this research, the silk web was hot-pressed for various times, the effect of press time on the structure and mechanical properties of silk non-woven fabric was also investigated. The yellowing appeared in the silk non-woven fabric and became more apparent as press time was increased. The crystallinity of silk was decreased by the hot press treatment and it did not change significantly with an increase of hot press time. The porosity of silk non-woven fabric was constantly decreased until 120 s and it did not change much after that. The thickness of silk non-woven fabric was significantly decreased by a press time of 10 s and slightly decreased with a further increase of hot press time. The hot press treatment increased the maximum stress and elongation of silk non-woven fabrics. The press time had a significant impact on the mechanical properties of silk non-woven fabric, with 90 s being the optimum condition for the best work of rupture of silk non-woven fabric.

• 한국공작기계학회논문집
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• 제10권6호
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• pp.109-115
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• 2001

This paper investigates the mechanical characteristics of angle-ply laminates with non-woven carbon tissue. The lami- nates were made by inserting non-woven carbon tissue at the interface. Specimens were rounded near the tabs by grinding and polishing to reduce the stress concentration. Cyclic loads were applied to the specimens and the stress and fatigue life curves were obtained. The matrix crack density was also evaluated to check the effects of non-woven carbon tissue on the fracture resistance of composite laminates. C-Sean technique was used to evaluate the delamination, and SEM was used to understand the fracture mechanisms of the laminates. Experimental results show that the fatigue strength and life of composite laminates were increased by inserting non- woven carbon tissues. The results also show that the matrix crack density and delamination area were reduced by inserting non-woven carbon tissues.

• 한국자원식물학회지
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• 제13권2호
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• pp.111-117
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• 2000

포도 품질을 높일 수 있고, 숙기 판단 노력을 절감할 수 있는 봉지 재료를 선발하고자 1997년부터 1999년까지 3년간에 걸쳐 충청북도 농업기술원 옥천포도시험장에서 시험한 결과를 요약하면 다음과 같다. 봉지내의 광 투과율은 종이 봉지에 비하여 부직포 및 무적비닐 이용 봉지에서 11∼65%가 높았으나, 무적비닐 천공 상면 50% 흰색 페인팅 봉지는 25% 낮았다. 과립중은 종이봉지에 비하여 부직포와 무적비닐이용 봉지에서 무거웠으며, 무적비닐 천공 상면 50% 흰색 페인팅 봉지는 열과, 탈립 및 부패과가 심하여 조사가 불가능하였다. 숙기는 종이봉지에 비하여 부직포와 무적비닐 이용 봉지에서 1∼4일 빨랐다. 당도는 부직포와 무적비닐 이용 봉지에서 높은 경향이었으나, 산도는 상반된 경향이었다. 착색정도는 종이 봉지에 비하여 부직포와 무적비닐 이용 봉지에서 빨랐으며, 이들 봉지간에는 착색 정도는 맥반석 혼합 부직포와 무적비닐+부직포 봉지에서 빨랐으나, 적숙기로 가까워질수록 부직 포봉지에서 빨랐다. 비정상 과립율은 종이와 부직포 봉지는 5.4∼7.0%로 낮았으나, 무적비닐 이용 봉지는 16.6∼100%로 높았다. 외관상품질은 부직포와 맥반석 혼합 부직포에서 지수 9.0으로 가장 좋았으나, 무적비닐 천공 상면 50% 흰색 페인팅 봉지는 지수 1.0으로 가장 불량하였다. 숙기 판단 소요시간은 종이(17.4시간/10a)에 비하여 부직포와 무적비닐 이용 봉지에서 74∼93% 절감되었다.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2000년도 추계학술발표대회 논문집
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• pp.110-114
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• 2000

The Interlaminar fracture behavior of hybrid composite with non-woven carbon tissue was investigated under Mode I (DCB) and Mode II (ENF) loading condition. Hybrid composites were manufactured by means of inserting a non-woven tissue between prepreg layers. Two kinds of specimens were prepared from [0]$_{24}$ and [$0_{12}/0_{12}$]. Where, the symbol "/" means that a non-woven carbon tissue was located at 0/0 mid-plane of the specimen. The interlaminar fracture toughness of hybrid composites was compared with that of CFRP. The fracture surfaces of the specimens were observed using optical microscope and SEM, and the failure mechanism was discussed. The hybrid laminates, which are made by inserting non-woven carbon tissue between layers, were shown to be effective to remarkably improve Mode II fracture toughness.toughness.

• Bulletin of the Korean Chemical Society
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• 제34권8호
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• pp.2441-2445
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• 2013

Chitosan non-woven fabrics were acetylated to improve their antimicrobial properties. The active chlorine content, antimicrobial properties, storage stability, and surface properties of acetylated chitosan non-woven fabrics were investigated. The active chlorine content of the fabrics increased upon reduction of the degree of the acetylation or increase in sodium hypochlorite concentration. Acetylated chitosan non-woven fabrics showed powerful antimicrobial activity by efficiently killing Escherichia coli and forming a growth inhibition zone for Staphylococcus aureus. Furthermore, scanning electron microscopy observations demonstrated that the acetylated chitosan non-woven fabrics were not damaged in sodium hypochlorite solution.

• 한국염색가공학회지
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• 제30권3호
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• pp.199-207
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• 2018

In this study, the properties of polypropylene(PP) non-woven fabric spun under various conditions by the Melt-blown method were verified, and the deodorant content and deodorization of PP non-woven fabric after deodorant-treatment were investigated. PP non-woven fabrics are manufactured by varying the temperature of spin beam, hot air temperature and amount, the RPM of collector R/O and the distance between collector and spinneret, which affects the structure of the non-woven fabric. After that, the structural characteristics and air permeability of the non-woven fabric were measured. The experimental results show that the amount of air, the distance between the collector and the spinneret significantly affect the structural characteristics and air permeability of the PP non-woven fabric. And, regardless of the weight of the PP non-woven fabric, the deodorizing effect of UiO-66 MOF deodorant add-on ratio and content was higher.

• 한국토양비료학회지
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• 제48권6호
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• pp.671-676
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• 2015

Control of surface runoff from upland soil is essential to reduce nonpoint source pollution. The use of non-woven fabric as a soil cover can be helpful to control surface runoff. The field experiment was conducted to evaluate the furrow cover effects of black non-woven fabric on the nutrient discharge from upland soil used for red pepper cultivation. The experimental plots consisted of chemical fertilizer (CF), cow manure compost (CMC), and pig manure compost (PMC) treatment. Each nutrient material treatment plot has control (no furrow cover (NFC)) and black non-woven fabric cover treatment, respectively. The amount of nutrient application was chemical fertilizer of $190-112-149(N-P_2O_5-K_2O)kgha^{-1}$, cow manure compost of $29.5tonha^{-1}$, and pig manure compost of $7.9tonha^{-1}$ as recommended amount after soil test for red pepper cultivation. Compared to control (NFC), furrow cover treatment with black non-woven fabric reduced the amount of T-N discharge by 50% at CF treatment, 36.9% at CMC treatment, and 44.8% at PMC treatment. Furrow cover treatment with black non-woven fabric reduced the amount of T-P discharge by 37.1% at CF treatment, 49.9% at CMC treatment, and 63.4% at PMC treatment compared to control (NFC). The production of red pepper did not show significant difference. There was no weed occurring in furrow cover treatment plots with black non-woven fabric. Results from this study showed that the furrow cover with black non-woven fabric could play a significant role in reduce nutrient discharge from upland soil used for red pepper cultivation.