Interfacial Characteristics of Epoxy Composites Filled with γ-APS Treated Natural Zeolite

이재영,이상근,김상욱,Lee, Jae-Young,Lee, Sang-Keun,Kim, Sang-Wook 한국접착및계면학회 2001 접착 및 계면 Vol.2 No.3

${\gamma}$-APS (${\gamma}$-aminopropyltriethoxysilane)로 표면처리된 천연제올라이트와 에폭시 수지 복합 재료의 표면 자유 에너지, 인상강도 및 계면 모폴로지에 대해 연구하였다. 표면처리하지 천연제올라이트의 표면 자유에너지 성분 중에서 무극성 성분인 Lifshitz-van der Waals 성분, ${\gamma}{\frac{LW}{SV}}$는 $19.22mJ/m^2$이었고, 극성 성분인 Lewis acid-base 성분, ${\gamma}{\frac{AB}{SV}}$는 $15.27mJ/m^2$이 있다. ${\gamma}$-APS의 처리농도가 증가함에 따라 ${\gamma}{\frac{LW}{SV}}$값은 증가하였지만 ${\gamma}{\frac{AB}{SV}}$는 감소하였으며, 이는 ${\gamma}$-APS의 소수성 성분인 알킬기의 영향이 친수성 기인 아민이나 수산기의 영향보다 커지기 때문이다. 인장강도와 Young율은 ${\gamma}$-APS 처리에 의해 개선되었으며, SEM 분석에 의해 계면특성이 향상되었음을 확인하였다. Epoxy composites filled with natural zeolite was prepared to investigate the effects of silane coupling agent, ${\gamma}$-APS (${\gamma}$-aminopropyltriethoxysilane)on the surface free energy, tensile properties and interfacial morphology. The value of Lifshitz-van der Waals component, ${\gamma}{\frac{LW}{SV}}$ for polar was $19.22mJ/m^2$ and increased, while that of Lewis acid-base component, ${\gamma}{\frac{AB}{SV}}$ for polar was $15.27mJ/m^2$ and decreased with the increasing content of ${\gamma}$-APS treatment. It is due that the surface of the zeolite is more coated by hydrophobic of alkyl group than hydrophilic amine or hydroxyl group. The tensile strength and Young's modulus of epoxy system were improved by the treatment with ${\gamma}$-APS due to the strong interface bonding, which was confirmed by SEM.

PET/CT 감쇠보정시 다양한 CT Kernel 적용에 따른 유용성 평가

이재영,성용준,윤석환,박찬록,이홍재,노경운,Lee, Jae-Young,Seong, Yong-Jun,Yoon, Seok-Hwan,Park, Chan-Rok,Lee, Hong-Jae,Noh, Kyung-Wun 대한핵의학기술학회 2017 핵의학 기술 Vol.21 No.2

PET/CT 영상 재구성시 감쇠보정맵을 사용하여 영상재구성에 적용한다. 감쇠보정 맵의 CT parameter을 변경하여 PET/CT 영상 재구성 할 때 적용하여 SUVmax에 어떤 영향을 미치는지 비교 평가해보고자 한다. 장비는 Biograph mCT 64를 사용하였고 Phantom은 NEMA IEC Body Phantom을 사용하였다. 실험을 위해 환자는 2017년 2월에서 3월까지 본원 PET/CT 검사를 시행한 환자 20명을 대상으로 Lung, Liver, Bone에 관심영역을 선택하여 기존 08f AC, 45f medium, 80f ultra sharp 방식의 CT kernel을 적용한 감쇠보정맵을 사용하여 PET/CT 영상 재구성에 도입 후 방사능 농도(kBq/mL), SUVmax, SD(standard deviation) 변화 유무를 평가하였다. Phantom 방사능 농도 측정 결과 B08f AC 대비 B45f 0.96%, B80f 6.58% 증가하였고 B08f AC 대비 B45f 0.86%, B80f 6.54%각각 증가하였고, SD의 경우 B08f AC 대비 B45f 1.27%, B80f 6.96% 증가하였다. 환자에서 부위별 SUV는 Lung에서 B08f AC 대비 B45f 1.6%, B80f 6.6%, Liver에서 B08f AC 대비 B45f 0.7%, B80f 4.7%, Bone에서 B08f AC 대비 B45f 1.3%, B80f 6.2% 증가를 보였다. 부위별 SD는 Lung에서 B08f AC 대비 B45f 6.2%, B80f 15.4%, Liver에서 B08f AC 대비 B45f 2.1%, B80f 11%, Bone에서 B08f AC 대비 B45f 를 사용할 때 2.3%, B80f 14.7% 증가를 보였다. CT Kernel변화에 따라 sharpness noise와 영상의 질은 변화를 보였으나 SUVmax와 SD는 통계적으로 유의한 차이가 없었다.(P>.05). 핵의학 영상은 정량적인 평가가 중요하다 따라서 부위에 따라 CT kernel이 적절하게 조절되고 noise level이 낮은 감쇠보정 맵을 사용하여 PET/CT 재구성시에 적용하여 정량적 평가에 오류를 줄이는 것이 중요하다고 사료되므로 따라서 같은 부위라 할지라도 sharpness noise가 인위적으로 증가된 kernel을 사용하는 것보다 noise가 낮은 kernel을 사용하는 것이 SD편차를 줄이고 정량적인 평가에 오류를 적게 하여 정확한 진단과 SUV 측정에 유용할 것으로 사료된다. Purpose Recently PET/CT image's attenuation correction is used CTAC(Computed Tomgraphy Attenuation Correction). it can quantitative evaluation by SUV(Standard Uptake Value). This study's purpose is to evaluate SUV and to find proper CT kernel using CTAC with applied various CT kernel to PET/CT construction. Materials and Methods Biograph mCT 64 was used for the equipment. We were performed on 20 patients who had examed at our hospital from february through March 2017. Using NEMA IEC Body Phantom, The data was reconstructed PET/CT images with CTAC appiled various CT kernel. ANOVA was used to evaluated the significant difference in the result. Results The result of measuring the radioactivity concentration of Phantom was B45F 96% and B80F 6.58% against B08F CT kernel, each respectively. the SUVmax increased to B45F 0.86% and B80F 6.54% against B08F CT kernel, In case of patient's parts data, the Lung SUVmax increased to B45F 1.6% and B80F 6.6%, Liver SUVmax increased to B45F 0.7% and B80F 4.7%, and Bone SUVmax increased to B45F 1.3% and B80F 6.2%, respectively. As for parts of patient's about Standard Deviation(SD), the Lung SD increased to B45F 4.2% and B80F 15.4%, Liver SD increased to B45F 2.1% and B80F 11%, and Bone SD increased to B45F 2.3% and B80F 14.7%, respectively. There was no significant difference discovered in three CT kernel (P >.05). Conclusion When using increased noise CT kernel for PET/CT reconstruction, It tends to change both SUVmax and SD in ROI(region of interest), Due to the increase the CT kernel number, Sharp noise increased in ROI. so SUVmax and SD were highly measured, but there was no statistically significant difference. Therefore Using CT kernel of low variation of SD occur less variation of SUV.

Electrodeposition of a Single Phase Cu2O Film by Current Pulsed Methods

이재영,남종우,탁용석,엄성현,강진욱 ( Jae Young Lee,Sung Hyun Um,Jin Wook Kang,Chong Woo Nam,Yong Sug Tak ) 한국공업화학회 1997 한국공업화학회 연구논문 초록집 Vol.1990 No.3

Kissinger Equation 과 Fractional Life 법에 의한 DGEBA / MDA / MN 계와 DGEBA / MDA / MN / HQ 계의 경화반응 속도론

이재영,심미자,김상욱 ( Jae Young Lee,Mi Ja Shim,Sang Wook Kim ) 한국공업화학회 1994 공업화학 Vol.5 No.4

DGEBA/MDA/MN계와 이 계에 촉매로서 hydroquinone(HQ)를 첨가한 계의 경화반응 속도론을 Fractional life법 및 Kissinger equation에 의해 연구함으로써 HQ가 경화반응 속도에 미치는 영향을 연구하였다. 경화반응 온도가 증가함에 따라 반응속도는 증가하였고, 반응차수는 약간의 변화가 있을 뿐 경화온도에 따른 경향성은 없었다. 촉매로 HQ를 첨가한 계가 첨가하지 않은 계보다 반응속도는 크게 증가하였고, 활성화 에너지는 13% 감소하였다. 이는 HQ의 히드록 시기가 에폭사이드기, 아민기와 반응하여 전이상태를 형성함으로써 에폭사이드 고리를 쉽고 빠르게 개환시켜 주기 때문이다. Cure kinetics of DGEBA/MDA/MN system with and without HQ were studied by Fractional life method and Kissinger equation. And the effect of HQ as a catalyst was studied As cure temperature increased, the reaction rate increased and reaction order was almost constant. The activation energy of the system with HQ was lower about 13% and the reaction rate was higher than that of the system without HQ. It was because hydroxyl group of HQ formed a transition state with epoxide group and amine group and opened the epoxide ring easily and rapidly.

유천분지내 화강암류와 광상구의 관계에 대한 지화학적 연구

이재영,김상욱,김영기,고인석,장태우,Lee, Jae Yeong,Kim, Sang Wook,Kim, Young Ki,Koh, In Seok,Chang, Tae Woo 대한자원환경지질학회 1990 자원환경지질 Vol.23 No.2

There is clear difference in content of the major and trace elements between Masan granites of Cu province and Yucheon-Eonyang granites of Pb-Zn province in the Yucheon Basin: the former has low content in K(2.08%), Na(2.42%) and Rb (127ppm), and high content in Ca(3.75%), Mg(1.42%) and Sr(304ppm) whereas the latter has high content in K(3.56-3.60%), Na(3.05-3.06%) and Rb(144-161ppm), and low content in Ca(0.62-0.96), Mg(0.21-0.26%) and Sr(136-157ppm). Ore metals in granites also show slight difference between two areas: Masan granites have slightly higher Cu content(18ppm) than Yucheon-Eonyang granites(13, 14ppm), whereas Yucheon granite(29ppm) has slightly higher Pb content than Masan granites(25ppm). Thus, it may be possible to apply geochemical difference of the granites to distinguish whether a Cretaceous granite mass is related to copper or lead-zinc mineralization, and whether it belongs Cu-province or Pb-Zn province in the Yucheon Basin.

연구논문 - 고분자공업분과 : Isoconversion 식에 의한 DGEBA / MDA / CTBN 계의 경화반응 속도론

이재영,심미자,김상욱 ( Jae Young Lee,Mi Ja Shim,Sang Wook Kim ) 한국공업화학회 1997 한국공업화학회 연구논문 초록집 Vol.1990 No.3

DGEBA - MDA - SN - Hydroxyl Group System 의 합성 및 복합재료 제조 : 2 . 섬유강화 복합재료의 파괴에너지

이재영,심미자,김상욱 ( Jae Young Lee,Mi Ja Shim,Sang Wook Kim ) 한국공업화학회 1994 공업화학 Vol.5 No.4

유리섬유/탄소섬유/에폭시 수지 hybrid 복합재료의 파괴에너지를 파괴메카니즘 측면에서 연구하였다. 에폭시 수지 매트릭스는 DGEBA(diglycidyl ether of bisphenol A)-MDA(4,4`-methylene dianiline)-SN(succinonitrile)-HQ(hydroquinone)를 사용하였다. 섬유강화 복합재료의 파괴에너지를 연구한 결과, 유리섬유와 매트릭스의 계면에서는 post debond friction energy가 가장 크게 나타났으며, debonding energy와 pull-out energy는 비슷한 값을 나타내었다. 탄소섬유와 매트릭스의 계면에서 파괴가 일어나는 경우에는 pull-out energy가 가장 큰 영향을 나타내었다. The fracture energy of glass fiber/carbon fiber/epoxy resin hybrid composite system was investigated in the aspect of fracture mechanism. Epoxy resin matrix was DGEBA-MDA-SN-HQ system. On the interface of glass fiber and matrix, post debond friction energy provided a major contribution to the fracture energy, and debonding energy and pull-out energy were of the similar value. In the case of fracture on the interface of carbon fiber and matrix, pull-out energy was the major contributor.

DGEBA / MDA / GN 계의 기계적 성질 및 파단 특성

이재영,심미자,김상욱 ( Jae Young Lee,Mi Ja Shim,Sang Wook Kim ) 한국공업화학회 1995 공업화학 Vol.6 No.2

DGEBA(diglycidyl ether of bisphenol A)/MDA(4,4`-methylene dianiline)/GN(glutaronitrile)계의 기계적 성질 및 파단 특성을 살펴보기 위해 GN의 함량에 따른 충격시험과 인장시험을 행하였고, SEM을 통하여 파단면을 관찰하였다. GN의 함량이 증가함에 따라 충격강도가 증가하였으며, GN 함량이 20phr인 경우에는 48% 개선되었다. 그러나 인장강도는 감소하였다. DGEBA/MDA 계의 파단면은 brittle한 형상을 나타내었고, GN이 첨가된 계는 상대적으로 ductile한 형상을 나타내었으며, 변형이 일어난 것을 확인할 수 있었다. To investigate the mechanical properties and the fracture characteristics of DGEBA/MDA/GN system, impact test and tensile test were performed with various GN contents. The fracture surface was observed by SEM. Impact strength increased with the increase of GN content and improved about 48% at 20phr of GN content. But tensile strength decreased with the increase of GN content. The fracture surface of DGEBA/MDA system without GN displayed typically brittle morphology, but that of the system with GN showed relatively ductile morphology and deformation was found.

영어의 모음체계 연구

이재영,Lee Jae-Young 대한음성학회 1999 말소리 Vol.38 No.-

In this paper I have surveyed vowel phonemes in a variety of English accents and have proposed the vowel systems of English. The English accents covered in this paper include General American English, Northeastern American English, Western American English, Southern British English, Northern British English, Scottish English, Southern Irish English, Northern Irish English, Australian English, and New Zealand English. The vowel systems proposed here reflect the acoustic information of vowels and phonological aspects of English. This paper offers an Optimality Theory-based analysis of the English vowel systems by appealing to independently motivated constraints. This paper, following Flemming(1995), makes an assumption that the vowel system in question is selected in output as an optimal candidate by a given constraint ranking, the assumption which is different from the view that the vowel system is fixed in input. The analysis proposed here gives an answer to why a specific vowel system is selected and why dialectal variations come about. It is shown in this paper that the vowel system selected in a specific dialect comes from an optimal satisfaction of a given constraint ranking and that dialectal differences result from dynamic permutations of the same constraints. The constraint-based analysis proffered here accounts well for the similarities and differences among dialects in regard to the vowel system.

EQCM를 이용한 금전극과 티타늄전극에서의 이산화납박막의 결정성장연구

이재영,엄성현,김두헌,최진섭,남종우,탁용석 ( Jae Young Lee,Sung Hyun Um,Doo Hun Kim,Jin Sub Choi,Chong Woo Nam,Yong Sug Tak ) 한국공업화학회 1997 한국공업화학회 연구논문 초록집 Vol.1997 No.0