• Applied Chemistry for Engineering
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• v.8 no.6
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• pp.1014-1021
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• 1997

Studies were carried out on the preparation of several kinds of pulps from Sponge gourd fiber by KP, ASP, SP PAP, AP and addition of AQ pulping process. These unbeaten and beaten pulping fibers were observed their characteristics and fiber structure by SEM, FQA, Image analyzer and Micro projector. The results were summarized as follows; 1) The cooking condition which is the possible defibrilation of Shives are KP base($160^{\circ}C$, 2hr.), ASP base($155^{\circ}C$, 4hr.), PAP base($160^{\circ}C$, 1hr.). From the results, the kappa no. had the range of 12, 25, 10 each other. 2) The pulp yields of sponge gourd fiber obtained the range of KP 50~55%, ASP&60~70% and PAP 45~50%. SP base have the highest and contnets of KP&PAP base are much the same as woods. 3) Increasing amount of NaOH on Pulping was accelerated the defibrilation of Shives and was changed a morphology of pulping fiber quality such as fiber length, curl and kink index. 4) Addition of AQ on pulping process of sponge gourd fiber had a affect to raise the rate of delignification while protecting cellullosic components against degradation, especially defibrilation was very excellent, beated pulp much more easily and increased the fibrilation. 5) ASP system have higher bulk density, fiber bonding and protecting cellullosic components against degradation than KP or PAP. 6) The color reactions of the "C" stain solution showed blue or blue-gray with clean and transparency thin cell wall.

• Proceedings of the Materials Research Society of Korea Conference
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• 2003.03a
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• pp.240-240
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• 2003

SiC 섬유의 고온강도를 향상시키기 위한 소결조제로 boron, aluminum 등을 사용할 수 있다. 본 연구에서는 폴리카보실란에 aluminum precursor를 첨가한 후 중합반응을 거쳐 Al-contained polycarbosilane을 합성하였다. 합성된 Al-contained polycarbosilane을 용융방사하여 섬유화 하고 열분해 공정을 통해 Si-Al-C-O 나노복합 섬유를 제조하였다. 먼저 aluminum butoxide와 polycarbosilane(commercial)을 200m1 xylene에 용해시켜 14$0^{\circ}C$에서 1시간 동안 reflux하였다. evaporator를 이용하여 xylene를 제거한 후 autoclave에서 25$0^{\circ}C$/30$0^{\circ}C$ 중합과정을 통해 가교결합 시켰다 이와 같이 합성된 시료는 ICP분석을 통해 aluminum 함량을 확인하였고 FT-IR(Fig.1) 및 GPC분석(Fig.2)으로부터 화학구조 및 분자량변화를 확인하였다. aluminum 첨가량이 증가함에 따라 Si-H/Si-$CH_3$의 결합크기의 비가 감소하였으며 이로부터 aluminum butoxide와 polycarbosilane의 가교결합이 이루어진 것으로 보이며 중합 후 분자량의 증가 또한 가교결합에 의한 결과로 사료된다 열무게감량(TGA) 측정 결과는 40$0^{\circ}C$부터 유기리간드의 분해가 일어나며 80$0^{\circ}C$이상에서 세라믹화 과정이 완료되었음을 알 수 있었다 또한 aluminum 첨가량이 증가함에 따라 세라믹 수율도 증가하였음을 확인하였다. 합성된 aluminum-contained polycarbosilane은 20$0^{\circ}C$에서 1시간 동안 불융화과정을 거쳐 환원 및 진공 분위기에서 고온 열처리하였으며 이로부터 얻어진 시료에 대해 XRD분석을 수행하였다. SEM과 TEM을 이용하여 미세구조를 관찰하였다.

• Korean Chemical Engineering Research
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• v.45 no.3
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• pp.264-268
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• 2007

The filtration performance of micron-sized metal fibrous filter was improved by synthesizing carbon nanotubes grown on the surface of metal fibers. The carbon nanotubes are grown with bush-like nanostructures covered around the micron-fibers or web-like nanostructures crossing between the fibers at different synthetic conditions. Filtration efficiency of CNT-metal-filter was measured and compared with the efficiency of the raw metal filter without CNTs. The developed CNT-metal-filter has higher filtration efficiency without significant difference in pressure drop compared with the conventional metal filter, which is because the carbon nanotubes function as the trap of pollutant nanoparticles.

• Applied Chemistry for Engineering
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• v.9 no.5
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• pp.715-718
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• 1998

In this work, bisphenol type vinyl ester was impregnated into the three-dimensional glass fabrics fabricated from different thickness changes. Their mechanical properties of the specimens have been investigated by three-point bending and flatwise compression tests. Also, interlaminar shear strength (ILSS) has been determined through short-beam test for the evaluation of interfacial adhesion at interfaces between fibers and matrix of the composites. The effect of thickness changes in three-dimensional glass fabric-reinforced composites have been described in this work.

• Composites Research
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• v.32 no.3
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• pp.127-133
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• 2019

Although carbon nanotubes(CNTs) have outstanding theoretical mechanical and electrical properties, CNT fibers(CNTFs) have not yet reached that level. Particularly, tensile strength is only about 10% or less, so studies for making up for it are being actively conducted. As a way for improving mechanical strength, methods such as synthesizing long CNT, orientation, chemical cross-linking, hydrogen bonding and polymer infiltration are being studied. In this review paper, we report preparation methods for highly conductive and strong CNTF/Carbon composites through coating and infiltration followed by carbonization of carbon precursor polymers such as polyacrylonitrile (PAN) and polydopamine (PDA) on CNTFs.

• Textile Coloration and Finishing
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• v.33 no.1
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• pp.1-9
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• 2021

This study aims to prepare the fabric with detoxification properties against chemical warfare agent by the simple treatment. For this purpose, polypropylene non-woven fabric(PP) was treated with polyethyleneimine(PEI) and guanidinylated PEI and detoxification properties of the guanidinylated PEI treated PP were evaluated using diisopropylfluorophosphate(DFP), as a chemical warfare agent simulant, and compared with the untreated and PEI treated PP. The half-lives of DFP on guanidinylated PEI treated PP and untreated PP were 334 min and 714 min, respectively. The half-life of DFP with guanidinylated PEI treated PP was 53.22% shorter than with untreated PP. This result shows that guanidine group in guanidinylated PEI treated PP was acted as a base catalyst for hydrolysis of DFP and decreased half-life of DFP. Therefore, it is expected that guanidinylated PEI treatment can be an simple pathway to prepare the detoxification fabric material for protective clothing against chemical warfare agents.

• Textile Coloration and Finishing
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• v.34 no.1
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• pp.10-19
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• 2022

Humectants are chemical compounds which added to water based pigment inks for DTP (Digital Textile Printing) to prevent evaporation of water. The humectants usually have diol or triol type chemical structures and their -OH groups have possibility to react with functional groups of the binder polymers, such as ester, carboxylic acid, and urethane groups, acting as a crosslinking agent. The crosslinking reactions between polymer binders and humectants in inks can affect touch of the printed fabrics. In this regard, this study aims to investigate effect of chemical structures and added amounts of humectants in pigment ink on touch of dyed fabrics by using 1,6-hexanediol, ethylene glycol, diethylene glycol, and 1,4-buthanediol with various amounts added to the mixture of a black pigment and a polyurethane type binder. Then, color, rubbing strength, touch of the fabrics dyed with the prepared pigment inks were evaluated.

• Journal of the Korean institute of surface engineering
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• v.57 no.1
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• pp.31-37
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• 2024

The surge in demand for lithium is primarily fueled by the expanding electric vehicle market, the necessity for renewable energy storage, and governmental initiatives aimed at achieving carbon neutrality. This study proposes a straightforward method for lithium extraction utilizing cellulose nanofiber (CNF) via a vacuum filtration process. This approach yields a porous CNF film, showcasing its potential utility as a lithium extractor and indicator. Given its abundance and eco-friendly characteristics, cellulose nanofiber (CNF) emerges as a material offering both economic and environmental advantages over traditional lithium extraction techniques. Hence, this research not only contributes to lithium recovery but also presents a sustainable solution to meet the growing demand for lithium in energy storage technologies.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1997.04a
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• pp.85-85
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• 1997

스트레스가 유발된 랫드의 대뇌에서 Vasopressin-catecholamine pathway의 활성도를 알아보기 위해 면역화학염색법으로 vasopressin 호르몬의 분비와 catecholamine의 생성변화를 tyrosine hydroxylase (TH) 효소의 발현변화로 규명하고, arginine vasopressin (AVP)과 V1 vasopressin receptor의 유전자 발현변화를 in situ hybridization 방법을 이용하여 살펴보았다. 수컷 SD rat를 7시간동안 stress cage에 넣어 16$\pm$1$^{\circ}C$의 물에 수침구속 스트레스를 준 후 대조군과 함께 관류고정하여 brain을 적출하였다. Brain의 hypothalamus 부위를 중심으로하여 동결절편하여 면역조직화학 염색과 in situ hybridization을 시행하였다. TH 면역조직화학 염색에서 대뇌의 줄무늬체 부위의 꼬리조가비핵에서와 시상하부 부위의 내측등쪽시상하부와 흑색질부위에서 스트레스군이 대조군에 비해 TH 면역염색성이 증가되어 관찰되었으나 시상하부 부위의 시삭위핵, 뇌실주위핵, 뇌실옆핵에서는 두 군간의 큰 면역염색성의 차이는 보이지 않았다. AVP 면역조직화학 염색에서는 시삭위핵에 많은 수의 AVP 양성 신경세포체들이 밀집되어 있으며 뇌실옆핵에서는 스트레스군에서 AVP 면역염색성이 약간 증가되어 관찰되었으나 신경섬유의 분포양상은 비슷하였다. 중간융기에서는 모두 강한 염색성의 신경섬유들이 관찰되어 두 군간에 큰 차이는 없었다. AVP 유전자에 대한 in situ hybridization 결과 시삭위핵의 신경세포에서 AVP mRNA 양성반응을 관찰할 수 있었으나 다른 시상하부핵에서는 관찰할 수 없었으며, V1 vasopressin receptor에 대한 in situ hybridization 결과는 두 군의 대뇌에서 모두 양성반응을 관찰할 수 없었으며 V1 vasopressin receptor 유전자의 조직별 발현정도와 스트레스에 의한 발현량 조절을 관찰할 필요가 있다고 사료된다.

• Korean Chemical Engineering Research
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• v.48 no.4
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• pp.457-461
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• 2010

After the industrial revolution, quantity production system has made the life of mankind rich and to fulfill the consumer's desire competitive power of the enterprise constantly make has made effort in quality, price and engineering department not remaining simple manufactures. But in such a change production lacked safety. Consequently, the main study studied in return domestic organization which produces a chemistry fiber rope to be used fact vessel or as a athletic equipment safety countermeasure. One of the assesment method on product liability, Checklist is showed that It can be used not as an evaluation but as a development factor of company. Also, checklist that used a study could expect that assist the company of management structure as well as improvement of product safety.