• Macromolecular Research
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• v.16 no.2
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• pp.128-133
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• 2008

Several dual-curable acrylic pressure-sensitive adhesives (PSA) were synthesized by the radical polymerization of acrylic monomers containing benzophenone, hydroxyl, and alkyl groups. The optimum extent of UV-induced cure was determined by varying the content of the benzophenone groups (the photoinitiator) from 0.5 to 1.5 wt%. The weight average molecular weight of the polymers obtained ranged from 300,000 to 700,000 amu. The coated pressure-sensitive adhesives were cured either by short UV exposure to induce the grafting of acrylic polymers, or by heating for 6 hat $60^{\circ}C$ to promote the reactions between the polyisocyanates and hydroxyl groups. The dual-curing behavior was determined by monitoring both processes quantitatively by infrared spectroscopy. The developed dual-curable acrylic pressure-sensitive adhesives were found to compensate for the limitations in UV-induced curing of thick coatings.

• Elastomers and Composites
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• v.55 no.4
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• pp.314-320
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• 2020

This study focused on experiments with polyethylene glycol (PEG) and glycidyl methacrylate (GMA), which are functional additives for water-expandable rubber. Polychloroprene rubber (CR)/superabsorbent polymer (SAP) composites were prepared and their cure behaviors, mechanical properties, water absorption rates, and surface morphology were measured based on the functional additives applied. When PEG and GMA were applied to the composites, the water absorption rate increased-including the initial rate-compared to that measured when functional additives were not used. The results also show that PEG has a hydrophilic functional group, which allows it to absorb more water, and GMA acts as a coupling agent between CR and SAP. However, with the introduction of functional additives, the cure rate slowed down and the mechanical properties also decreased.

• Proceedings of the SCSK Conference
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• 2003.09b
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• pp.26-31
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• 2003

Korean Ginseng is a medicinal herb which grows naturally in korea. an ancient country situated in north-eastern Asia. Its medical use was already well known to herb doctors in this region about five thousand years ago since the effectiveness of korean ginseng has been recognized through practical use for a long time. Korean Ginseng has always been regarded as a devine cure. The name "Ginseng" can be found in various medicinal books. many of which were written as early as B.C. 100. In the records of many chinese medical books. dating from the inception of publishing, it was noted that Korean Ginseng was of the highest level of quality. Korean Ginseng originally grew in the mountains of korea. However, this wild Korean Ginseng(js called SANSAM) could not meet the ever-increasing demands. and from the 16th century. it has been cultivated on farms for mass processing and supplying in korea(js called INSAM). It was already recognized in korea a long time ago(B.C. 57 - A.D. 668) that Korean Ginseng possessed the qualities of panacea, tonic and rejuvenator, and had other medicinal properties as well. The effectiveness of Korean Ginseng is widely recognized among south-eastern Asians as well as Chinese. As its effect has been proved scientifically. Korean Ginseng is now becoming the ginseng for all human beings in the world. Korean ginseng is differently called according to processing method. Dried thing is Insam(white ginseng), boiled or steamed is Hongsam(red ginseng). 장뇌삼(long headed ginseng) is artificially grown in the mountain no in field for a long time. So the body is thin and some long. but ingredients are concentrated. Korean wild ginseng(SANSAM) is rare in these days but we developed cosmetic ingredient. The scientific name of Korean Ginseng is Panax Ginseng. It has acknowledge as a natural mysterious cure among the notheastern peoples. because of its broad medicinal application. The origin of the word" Panax" derived from panacea. a Greek word meaning cure-all. According to the classification method of herb medicines in the Chinese medicinal book. "God-Farmer Materia Medica(A.D. 483-496) korean Ginseng was described as the superlative drug: panacea. tonic and rejuvenator. We studied skin immunological effect. collagen synthesis. cell growth and whitening effect of SANSAM extract. IN cosmetics.. SANSAM extract had skin fibroblast cell growth effect. recover damaged skin in the sun and protect fine wrinkle. Also. In hair product.. inhibits hairless, white hair.its hairless, white hair.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.05a
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• pp.13-17
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• 2000

In EPDM/ATH/clay compounds, clay rich compounds show lower tensile strength due to lower cure state derived from acidic nature of clay filler. As the ATH is replaced by clay, dielectric properties such as $tan{\delta}$, dielectric constant and volume resistivity improve, Polar nature of ATH is responsible for the higher hot water ingress. The amount of charge in the EPDM/clay compounds increases with an increase of clay concentration.

• Journal of the Korean Society of Propulsion Engineers
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• v.20 no.1
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• pp.37-42
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• 2016

In this study, we examined the burning rate of the uncured propellant (with and without a curing agent application) in order to inspect the process of the HTPB solid propellant. The burning rate of the uncured propellant, that did not contain the curing agent, was approximately 9.7 mm/s at 1000 psi. In relation to the curing time, the burning rate was constant. The propellant, with the curing agent application, was approximately 8.1 mm/s showed a tendency of slowing as it burned. When the cure reaction rate was low, in accordance to the time, there were small changes in burn rate. However, when the cure reaction rate was high, the difference in burning rate was increased. The burning rate of a fully-cured propellant was approximately 6.8 mm/s, which appeared to be the lowest in order.

• CELLMED
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• v.13 no.2
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• pp.2.1-2.9
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• 2023

CPS219, a new concept compound composed of coffee (CO), Pueraria Tomsonii flower (PF), and Sambou bamboo salt^TM (BS), was developed as a coffee beverage to alleviate menopausal symptoms. The purpose of this study is to evaluate the anti-oxidant and menopausal alleviating effects of CPS219 combined as the optimal ratio of each component selected through sensory evaluation and blind consumer test. For CPS219, the optimal ratio of CO, PF, and BS was determined to be 1:0.1:0.017 through various sensory evaluations and blind consumer tests. CPS219 significantly enhanced the superoxide dismutase-like activity compared to the CO or CO plus PF (CP). The proliferation of MCF-7 cells was considerably increased after 24 hours by treatment with CO, CP, or CPS219, but only CPS219 significantly boosted the proliferation of MCF-7 cells after 48 hours. Moreover, CPS219 had an estrogen-like effect by dramatically increasing the expression of estrogen receptor-β mRNA in MCF-7 cells but not CO and CP. Treatment of MCF-7 cells with CO, CP, or CPS219 did not cause any cytotoxicity. In conclusion, these findings imply that anti-oxidant and estrogen-like properties of CPS219 can be used to prevent and cure postmenopausal symptoms.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2002.11a
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• pp.218-226
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• 2002

제지분야에서 중성 사이즈제로 광범위하게 사용되어지는 AKD emulsion의 사이징 효과의 발현속도가 낮은 단점을 보완하기 위하여, 기존 AKD emulsion에 추가 투입 사용함으로써 발현속도를 높여줄 수 있는 AKD 급속 반응형 정착제, 그리고 정착제를 사용하지 않는 초지 시스템에서도 급속 경화가 가능한 급속 반응형 AKD emulsion을 개발 하였다. AKD 급속 반응형 정착제의 투입량 및 종이 건조시간에 따른 사이징 효과를 상용화된 정착제와 비교하였으며 이 결과로부터 보다 빠른 사이징 효과발현을 확인하였다. 정착제를 사용하지 않는 시스템에서 급속반응형 AKD emulsion의 사이즈도 급속발현 효과를 확인하기 위하여 상용화된 emulsion과 사용량에 따른 사이징 효과와 건조시간에 따른 사이징효과를 비교함으로서 사이즈도의 급속 발현을 확인 할 수 있었다.

• Journal of the Korea Institute of Military Science and Technology
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• v.20 no.5
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• pp.620-632
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• 2017

A chemical vapor curing method(CVC) was developed to cure polycarbosilane(PCS) fibers by using cyclohexene vapour as a non-oxygen active reactant, instead of air in oder to prepare the silicon carbide(SiC) fiber with low oxygen content. A cross-linked PCS fibers by cyclohexene vapor showed a completely different variation in IR spectra in comparison to the air-cured PCS fiber. CVC method resulted in less than 3 wt% in oxygen content. In this experiment conditions, The average tensile strength and modulus of SiC fiber obtained by CVC had 1995 MPa and 183 GPa respectively, which is higher than that of SiC fiber prepared by air-curing process.

• Elastomers and Composites
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• v.31 no.5
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• pp.347-352
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• 1996

A natural rubber was blended with a butadiene rubber with different ratios. A natural rubber, along with three different blends, its ratio varying from 10 to 15 to 20 weight %, were prepared and tested. It was found that inclusion of the butadiene rubber increased cure time, compared to the natural rubber. It is speculated that increased free volume due to the inclusion of butadiene rubber contributed to this effect. Furthermore, inclusion of butadiene rubber led to increase hardness of a sphere, and as a result, the extent of rebound increased sharply.

• Nuclear Engineering and Technology
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• v.1 no.1
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• pp.23-31
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• 1969

Whole cure shrimp, eviscerated common squid and little squid meats were irradiated with gamma radiation from 60Co using varying dose up to one Mrad. Changes in quality were assessed by organoleptic, chemical (VRS and TMA-N), biochemical (hypoxanthine) and microbiological tests； and the effect of radiation on prolonging of the storage life at 2-4 C was studied. With the cure shrimp, 0.12-0.20 Mrad appears to be optimal with 8 days of storage life, whereas the unirradiated control samples had a storage life of 3 days. With the common squid meat, 0.20-0.30 Mrad appears to be optimal with 14-21 days of storage life, where-as the unirradiated control samples had a storage life of 8 days. And for the little squid meat, 0.12-0.20 Mrad appears to be optimal with 10 days of storage, where-as the unirradiated control samples had a storage life of 5 to 6 days.