• 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.

• Journal of the Korean Electrochemical Society
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• v.5 no.3
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• pp.117-124
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• 2002

Poly(acrylonitrile)(PAN) solutions in dimethylformamide(DMF) were electrospun to prepare webs consisting of 400nm ultra-fine fibers. The webs were oxidatively stabilized, activated by steam and resulted to be activated carbon fibers(ACFs). The specific surface area was $800\~1230 m^2/g$, which showed a trend of a decrease of the surface area with an increase in activation temperature, showing opposite behavior to the other ACFs. The activation energy of the stabilized fibers for the steam activation was determined as 29.2 kJ/mol to be relatively low indicating the easier activation than that of other carbonized fibers. The ACF webs were characterized by pore size and specific surface uea which would be related to the specific capacitance of the electrical double layer capacitor (EDLC). The specific capacitances measured were 27 F/g, 25 F/g, 22 F/g at the respective activation temperature of $700^{circ}C,\;750^{\circ}C\;800^{\circ}C$, showing similar trend with the specific surface area i.e., the higher activation temperature was, the lower specific capacitance resulted.

• Economic and Environmental Geology
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• v.49 no.1
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• pp.1-11
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• 2016

Chrysotile is well known as a fibrous mineral in serpentinite by the previous studies in S. Korea. Previous studies in other countries showed that antigorite also occurred as asbestiform and harmful to humans. Therefore, the objective of this study was to investigate types and characteristics of fibrous serpentine minerals occurred in serpentinite in Hongseong, Chungnam and Gapyeong, Gyeonggi in S. Korea. XRD, SEM-EDS, PLM and EPMA mapping analyses were used to examine the occurrence and formation mechanism of serpentine minerals. Serpentinization partially occurred in amphibole-schist and calc-schist at two study sites, Hongseong, Chungnam and Gapyeong, Gyeonggi, respectively. Both chrysotile and antigorite occurred as a fibrous mineral at Hongseong site, but chrysotile occurred as a fibrous mineral at Gapyeong site. Based on PLM analysis with dispersion staining, the chrysotile was observed horizontally magenta and vertically blue colors. The antigorite appeared as horizontally gold to golden magenta and vertically blue magenta colors under central stop dispersion staining objective(DSO). PLM and SEM analyses showed the fibrous minerals were formed from plate form of serpentine minerals or by hydrothermal alternation of primary minerals. The EPMA mapping showed that Mg contents in chrysotile is relatively higher than that in antigorite while Si and O contents in antigorite is higher than them in chrysotile. However, more studies are necessary to know the exact variation in chemical composition of chrysotile and antigorite. These results indicate that even though asbestiform antigorite found associated with asbestos chrysotile in serpentinites, the fibrous antigorite can be distinguished from chrysotile by different dispersion staining colors.

• Polymer(Korea)
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• v.25 no.4
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• pp.575-586
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• 2001

Stabilized polyacrylonitrile (PAN) fibers can be transformed into quasi-carbon fibers with different properties depending on heat-treatment processing parameters at lower temperatures than temperature for the fabrication of carbon fibers. It has been investigated from the preliminary work that appropriate quasi-carbonization processes at about 1100$^{\circ}C$ strongly influence various properties of quasi-carbon fiber/polymer composite as well as quasi-carbon fiber itself. The objective of the present work is to prepare quasi-carbon fibers from stabilized PAN fibers using various quasi-carbonization cycles and to examine their properties. Two temperature regions, up to 800$^{\circ}C$ and above 1000$^{\circ}C$, were used for quasi-carbonization processes. The chemical composition, physical properties, thermal stability, microstructure, mechanical properties and electrical resistivity of the quasi-carbon fibers prepared with different final heat-treatment temperatures, heating rates, holding times, heating steps, and purging gas purity were extensively examined. The results were also compared with those from stabilized PAN fiber and commercial PAN-based carbon fiber. The present study showed that a variety of properties of quasi-carbon fibers significantly depended on several quasi-carbonization process parameters.

• Venture DIGEST
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• s.92
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• pp.36-37
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• 2006

멕시코는 잠재적 시장성과 아메리카 대륙의 교두보로서의 중요성에 비해 우리에게는 그리 잘 알려지지 않은 시장이다. 몇몇 대기업과 섬유·화학 중소기업이 직접투자 형태로 진출해 있을 뿐 중소기업들 대부분은 초기단계에 머물고 있다. 멕시코 시장의 잠재력과 가능성을 소개함으로써 기술력 있는 중소·벤처기업들의 멕시코 진출이 늘어나는 계기가 되었으면 한다.

• The Magazine for Energy Service Companies
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• s.53
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• pp.30-31
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• 2008

우리에게 익숙한 폴리에스터나 나일론(폴리아마이드)은 2개 이상의 단위체를 결합하여 만든 고분화 화합물이며 이들을 만드는 과정을 중합반응이라고 한다. 예를 들면 폴리에스터의 경우, PTA(Purified Telephtal Acid)와 Ethylene Glycol을 약 $280^\circC$의 고온과 0.4torr 정도의 진공에서 합성해 만들어 진다. 이 반응에 필요한 진공 조건을 유도하기 위해 Ejector가 필요한데 우리나라의 화학 섬유 공장에서는 주로 증기를 이용한 Ejector를 사용하고 있다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.10a
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• pp.751-752
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• 2012

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2004.04a
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• pp.181-191
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• 2004

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 1999.06a
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• pp.111-114
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• 1999

습도 제어가 안전관련분야에서 점차 그 비중이 증가하여 안전방재용 습도센서로 금수성 물질 및 기타 위험물의 저장, 핵발전소의 반응기, 고압보일러, LPG 이송 및 저장, 화학 plant 등의 습도제어 분야에 사용되고 있으며 이 외에도 섬유, 식품, 전자 등의 산업분야에서 안전 범위내의 습도 유지 및 검출을 목적으로 널리 사용된다. (중략)

• Textile Coloration and Finishing
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• v.9 no.1
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• pp.61-68
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• 1997

용제법에 의한 New Rayon(이하, 상표명 Tencel로 호칭) 는 영국 Caurtaulds 사에 의해, 방사공정에서의 제조기술이 장기간에 걸친 오랜 동안의 연구개발을 계속한 노력의 결과로 탄생된 것인데, 그 경위를 간추려보면 다음과 같다.