• Journal of Biomedical Engineering Research
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• v.18 no.2
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• pp.173-178
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• 1997

pH sensitive polymers have long been utilized as one important type among many interesting drug delivery systems. This is due to the reason of different pH environments in human organs, which requires different pH control mechanism depending upon the organs. In the present study the pH sensitivity was investigated for both pH sensitive and pH insensitive biopolymers using the diffusion effect along with the swelling effect. NMR microscopy was performed along with optical microscopy. For the analysis of diffusion effect, UMR Microscopy was perFormed to measure diffusion coefficients for various liquids such as distilled water, acetone and DMSO(dimethyl sulfoxide). Also, this technique is expected to contribute to the studies for many pH drug delivery systems.

• Journal of Biomedical Engineering Research
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• v.18 no.2
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• pp.167-172
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• 1997

Novel measurement method has been performed for the noninvasive study of the swelling effect detected in hydrophilic polymers using Magnetic Resonance Microscopy. iN NMR images were acquired to measure geometric changes due to the swelling effect occurred in the polymer specimens. In addition to the geometric changes, the water ingress process was visualized noninvgsively. The measurement method performed .in the present study utilized some of NMR's valuable properties, both noninvasiveness and parameter selectivity. It is believed that the method used in the present study may be applicable to the study of biopolymers in which noninvasiveness is particularly important.

• Journal of the Korean Chemical Society
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• v.47 no.2
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• pp.133-136
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• 2003

A series of oxazolone derivatives (4a-n) have been synthesized as a potential antibacterial agent. Titled compounds have been prepared by the condensation of aryloxy acetyl-amino-acetic acid with aldehyde in presence of ethanol, acetic anhydride and sodium acetate. The structures of the new compounds were established on the basis of $^1H$ NMR and IR spectral data.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 1998.10a
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• pp.109-114
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• 1998

한우산업의 국제경쟁력 향상과 소비자가 요구하는 고급육을 생산하기 위해서는 도축전에 살아있는 가축으로부터 육질과 육량을 판정할 수 있는 기술의 개발이 요구되고 있다. 생체상태에서 도체특성을 추정할 수 있는 기술로서는 초음파, X-선 및 핵자기공명 등이 있지만 실용화가 가능한 방법으로는 초음파 기술을 대표할 수 있다. 초음파 기술을 이용하여 살아있는 소의 등지방두께와 등심단면적을 추정하는데에 대해서는 높은 정확도를 갖고 있어 일부 국가의 종축선발 기관이나 비육장에서는 정육생산능력을 예측하는데 효과적으로 이용하고 있지만 근내지방도의 추정능력과 실용화는 아직 연구단계에 있다. 우리나라의 초음파 기술 이용실태는 아직 연구단계에 있다고 할 수 있지만 1990년대에 접어들면서 학계와 연구계 및 산업현장에서 기기의 정확도를 향상시키고 현실에 적합한 기기를 개발하고자 노력하고 있으므로 그 효과는 곧 가시화될 것으로 기대된다.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.05a
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• pp.36-37
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• 2015

The purpose of this study is to investigate pozzolanic reactivity of the rice straw ash. This study focused on rice straw ash properties at various burning temperature and duration as a mineral admixture for mortar and concrete, and provide the crystalline state and molecular structure of rice straw ash. X.R.D and N.M.R were performed on rice straw ashes to identify pozzolanic reactivity.

• 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 KOR-BRONCHOESO Conference
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• 1991.06a
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• pp.38-38
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• 1991

콜레스테롤 육아종은 콜레스테롤 결정이 주위조직에 이물질로 작용하여 육아성 반응 및 골파괴 반응을 유발시키는 질환으로 병리조직학적으로 많은 콜레스테롤 결정이 거대세포를 가진 만성적인 염증성 침윤속에 나타나는것을 특징으로 한다. 이 병변은 아주 드물지만 특징적인 방사선적소견, 병리조직학적 소견과 임상양상으로 쉽게 진단이 된다. 두부에서는 다양한 위치에서 발견되는데 특히 함기화가 잘 된 측두골, 유양동, 고실강에서 많이 보이며 전두골, 상악골, 협골, 인상측두골 및 후두개와에서도 보고되고 있으나 부비동에 발생하는것은 특히 드물다. 부비동에서 발생한 콜레스테롤 육아종의 발생기전은 환기장애설, 배출장애설 및 출혈설 등으로 보고되고 있다. 저자들은 최근 복시와 측두통을 호소하는 50세 여자환자에서 접형동에 발생한 콜레스테롤 육아종이 우측 상안와열 (superior orbital fissure)과 경사대(clivus)를 파괴하며 전교조 (Prepontine cistern)로 확장된 1례를 경험하였기에 임상 증세, 특징적인 전산화단층 및 핵자기공명소견과 병리조직학적인 소견을 문헌 고찰과 함께 보고하는 바이다.

• Journal of Chest Surgery
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• v.32 no.9
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• pp.855-857
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• 1999

Lymphangioma(or cystic hygroma) of the chest wall is rare case. We experienced one such case in a 16-year-old girl who complained of a large recurrent mass on her right upper post erolateral chest wall which had developed several years ago. The diagnosis was made following a physical examination, chest magnetic resonance imaging(MRI), and radio isotope (RI) lymphangiogrphy and was confirmed by a histopathological examination. We performed total excision of the lesion followed by a repeated sclerosing therapy with intralesional injection of Vibramycin.

• Korean Journal of Microbiology
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• v.23 no.4
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• pp.302-308
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• 1985

It is shown by means of nuclear magnetic resonance spectroscopy that 3,4,5-trihydroxy-2-keto-L-valeraldehyde (L-xylosone), an ${\alpha}$-ketoaldehyde, is formed during the oxidative catabolism of L-ascorbic acid. It is proposed that this substance serves as a substrate for the glyoxalase system by which it is transformed to L-xylonic acid. As L-xylonic acid is further oxidized to L-erythroascorbic acid, a biochemical pathway is proposed for the action of vitamin C which consists of two further ${\gamma}$-lactones and three different substrates of the glyoxalase system.

• Korean Journal of Microbiology
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• v.25 no.4
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• pp.304-308
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• 1987

The mode of transglycosylation reaction observed during the action of low-molecular-weight 1,4-$\beta$-D-glucan glucanohydrolase (EC 3.2.1.4) purified from Trichoderma koningii ATCC 26113 was investigated using $^{1}H-NMR $spectroscopy. The H-1 proton resonances were analysed. After reaction of the enzyme with cellotriose, the reaction products were separated by high performance liquid chromatography. H-1 resonances of the products were consisted with those of cellobiose, cellotriose and cellotitraose, respectively. Therefore it was proved that all the reaction products formed by the action of the enzyme on cellooligosaccharides, including transglycosylation products, possess only H-NMR -1,4-glycosidic linkage(s).