• Analytical Science and Technology
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• v.17 no.2
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• pp.98-107
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• 2004

In this study, $^1H$ NMR spectroscopy and HPLC were used to identify the type and quantity of each component in an acrylic coating materials applied for an automotive part. By the $^1H$ NMR analysis, it was found that this acrylic coating contained about 88.40 wt% of poly methyl methacrylate (PMMA), 7.05 wt% of methyl methacrylate (MMA), and 2.36 wt% of allyl methacrylate. Polymer additives such as a benzotriazole light stabilizer (Hisorb 328), an oxanilide light stabilizer, butylated hydroxy toluene (BHT), and dimethyl phthalate (DMP) were also identified and measured quantitatively from the $^1H$ NMR spectra. However, only two light stabilizers were identified by reverse phase (RP) HPLC analysis using Bondapak C18 column, methanol mobile phase, and a PDA (Photodiode array) detector. The contents of two light stabilizers in the acrylic coating were measured by a quantitative analysis through UV-Vis spectroscopy and compared with the NMR data. The analytical informations from $^1H$ NMR spetra were better than those from HPLC-PDA plot.

• Korean Journal of Crystallography
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• v.12 no.3
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• pp.141-144
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• 2001

From the reaction of Na[Ga(N₃)₄] with PPh₃, an ionic compound [Ph₃P(OH)]/sup +/[N₃]/sup -/ (1) was isolated. Compound 1 was characterized by spectroscopy (¹H-NMR, /sup 13C{¹H}-NMR, and IR) and X-ray diffraction. Crystallographic data for 1 : orthorhombic space group P2₁2₁2₁, a = 10.491 (4) Å, b=11.603(5)Å, c=13.149(5)Å, Z=4, R(wR₂)=0.0547(0.0978).

• 한국신재생에너지학회:학술대회논문집
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• 2008.10a
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• pp.178-181
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• 2008

다양한 조성을 갖는 $CH_4+CO_2$ 혼합 기체 하이드레이트 샘플의 미세 구조 분석을 위하여 X-ray 회절 방법을 이용하였다. X-ray 회절 분석을 이용할 경우, 하이드레이트로의 전환율과 같은 정성적인 분석뿐 아니라 각 객체별 cage occupancy와 같은 정량적인 분석까지도 가능한 것으로 나타났다. 또한 이렇게 얻어진 X-ray 회절 분석 결과 및 refinement 결과를 $^{13}C$ 고체 NMR 방법과 교차 비교함으로써 측정 결과의 신뢰도를 높이려 하였다. 얻어진 분석 결과는 이후 가스 하이드레이트를 이용한 다양한 연구 분야에서 저장용량 평가 및 객체 점유율과 같은 미세 구조 정보를 얻는 데에 유용하게 사용될 것으로 전망된다.

• Journal of the Korean Chemical Society
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• v.38 no.1
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• pp.41-49
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• 1994

Exchange reaction mechanisms of the Pb(II) ion for the complexes between Pb(II) ion and nitrogen oxygen donor macrocyclic ligands, such as 1,13-diaza-3,4 : $1011-dibenzo-59-dioxacyclohexa-decane(NtnOtnH_4)$, 1,15-diaza-3,4 : $1213-dibenzo-5811-trioxacycloheptadecane(NenOdienH_4)$, and 1,15-diaza-3,4 : $1213-dibenzo-5811-trioxacyclooctadecane(NtnOdienH_4)$, were studied by $^{207}Pb-NMR$ spectroscopy in N,N'-dimethylformamide(DMF) solutions. The associative-dissociative mechanism dominated in $NtnOtnH_4-Pb(II)$ and $NtnOdienH_4-Pb(II)$ system. For $NenOdienH_4-Pb(II)$ system, the bimolecular exchange mechanism prevailed below $-5^{\circ}C$, and both bimolecular exchange and associative-dissociative mechanism dominated above $+5^{\circ}C.$ The order of activation energies for dissociation was $NtnOdienH_4\;<\;NtnOtnH_4\;<\;NenOdienH_4$ which was reverse to the order of stabilities.

• Journal of the Korean Chemical Society
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• v.37 no.7
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• pp.662-671
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• 1993

New Ni(II) and Pd(II) complexes of isonitrosomethylacetoacetate imine derivatives, Ni(IMAA-NH)(IMAA-NH'), Ni(IMAA-NH)(IMAA-NR), $Pd(IMAA-NH)_2\;and Pd(IMAA-NR)_2(R=CH_3,\;C_2H_5,\;n-C_3H_7,\;n-C_4H_9,\;or\;CH_2C_6H_5)$, where H-IMAA-NH and H-IMAA-NR represent isonitrosomethylacetoacetate imine and N-alkylisonitrosomethylacetoacetate imine derivative, respectively, have been prepared and the structures of the complexes have been studied by elemental analyses, electronic, infrared, and $^1H-\;and\;^{13}C-NMR$ spectroscopies.

• Journal of the Korean Chemical Society
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• v.36 no.3
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• pp.351-359
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• 1992

Interaction of xenon with alkaline-earth cations in Y zeolite supercage was studied by xenon adsorption and $^{129}Xe$ NMR experiments. The CaY and the BaY samples were prepared by exchanging $Ca^{2+}$ and $Ba^{2+}$ into a high-purity NaY zeolite. Xenon adsorption isotherms of these samples were obtained by using a conventional volummetric gas adsorption apparatus in the range of 260 to 320 K and the chemical shift in the $^{129}Xe$ NMR spectrum of the adsorbed xenon was measured at 296 K. The chemical shift against pressure was quantitatively explained assuming that the xenon gas exchanged very rapidly between various adsorption sites consisting of zeolite-framework surface and alkaline-earth ion. From this analysis, it was found that the alkaline-earth ion adsorbed xenon more strongly than $Na^+$ ion and zeolite-framework surface. Baring on the difference of the adsorption strength, the number of the alkaline-earth cations present in the zeolite supercage could be estimated by analyzing the adsorption isotherm.

• Journal of the Korean Chemical Society
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• v.43 no.6
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• pp.682-690
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• 1999

The quaternary random copolyesters of poly (butylene glutarate-co-adipate-co-succinate-co-terephthalate)(PBGAST) were synthesized and charaterized by $^1H-NMR$ spectrometry, DSC method, and X-ray diffractometry. Thus the melting point trends and crystallization behaviors of PBGAST copolyesters were obviously depended on terephthalate content in copolymers as well as reaction condition.

• Journal of the Korean Graphic Arts Communication Society
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• v.19 no.1
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• pp.17-27
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• 2001

플라티늄포르피린 핵과 주위에 8, 16, 32 그리고 64 개의 벤질 단위를 갖는 새로운 덴드리머를 압력 감지형 페인트에 사용할 발광체로 합성하였다. 플라티늄포르피린 핵을 갖는 제 1 세대의 덴드리머는 Lindsey형 합성법을 이용하여 제조하였으며, 제 2 세대에서 제 4 세대까지의 플라티늄포르피린 핵을 갖는 덴드리머는 플라티늄 테트라키스(3,5-디히드록시페닐)포르피린을 적합한 덴드론 브로마이드와 Williamson 에테르 합성법에 따라 알킬화반응시켜 제조하였다. 이러한 에테르 연결의 생성 반응들은 $K_2$CO$_3$와 18-크라운-6를 사용하여 아세톤 용매에서 질소 기류 하에서 6$0^{\circ}C$에서 수행하였을 때 가장 좋은 결과를 주었다. 그리고 이렇게 합성한 덴드리머들을 $^1$H-NMR, $^{13}$C-NMR, Mass spectrum 이용하여 구조를 확인하고, 그리고 UV-VIS spectroscopy를 이용하여 분광학적인 특성을 조사하였다.

• Journal of the Korean Chemical Society
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• v.29 no.3
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• pp.247-251
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• 1985

Dichloro cobalt(III) complex of a flexible tetradentate ligand of ethylenediamine-N,N'-di-S-${\alpha}$-propionic acid (eddp) has been prepared via the air-oxidation technique. Only ${\Delta}$-cis isomer has been yielded showing high stereoselectivity of the eddp ligand. Elemental analysis, ir, nmr and electronic absorption spectra have been used to characterize the complex and the absolute configuration of the complex is assigned by means of the nmr spectroscopy.

• Proceedings of the KOSOMBE Conference
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• v.1993 no.11
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• pp.63-66
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• 1993

Localized NMR spectra were obtained from phantom by OSIRIS technique. The selected volume, which can be controlled by frequency and its bandwidth, was 0.125cc out of 25cc and free of contamination from outer volume. With this technique NMR spectrum of a living tissue can be obtained without biopsy. i.e. in vivo state in which the metabolism of tissue may be quite different from in in vitro state. It is expected of this technique to be useful in the study of metabolism of living tissue as well as in diagnosis of deseases.