• Journal of the Korean Graphic Arts Communication Society
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• v.13 no.1
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• pp.73-91
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• 1995

Spectroscopic and Photoelectric Characteristics in the Cyanine and Merocyanine Dye according to systematically change of their structures were experimentally discussed. As result, in solution, Hetero atoms(X) of Cyanine and Merocyanine dye were participated in resonance X of d obital rather than X of pobital,effected in resonance and contributed in extension of conjugated system. in solid film,new spectra,called eximer-fluorenscence,were appeared in 3-dimensional fluorenscence of high density of Cyanine dye but not of Merocyanine. The activational energy of conductivity in Merocyanine dye was lower than in cyanine, an the contrary,the drift mobility was higher and the former in photoelectric characteristics was more effec-tive than the latter. In this paper,authors invertigated the changes of dye structure by molecular obital method to confirm the results of spectroscopic and photoelectric characteristics in the Cyanine and Merocyanine Dye acco-rding to systematically cally change of their structure, and counted total energy on dihedral angle and dipol miments if dyes in S0 and S1.

• Journal of the Korean Magnetic Resonance Society
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• v.15 no.2
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• pp.128-136
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• 2011

A new sesterterpenoid, phorbaketal derivative, was isolated from the marine sponge Phorbas species. Its planar structures was completely determined from a combination of extensive 1D and 2D NMR experiments and MS data, and also the stereochemistry on the chiral centers were established by the ROESY experiment and the comparison with the $^1H$ and $^{13}C$ chemical shifts of the known phorbaketal compounds. This compound 1 moderately showed cytotoxicity effect against hepatoma cancer HepG2 cell.

• Journal of the Korean Magnetic Resonance Society
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• v.14 no.1
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• pp.1-8
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• 2010

Four 5,8-epidioxy sterols were isolated from the marine sponge Plakortis simplex. Their structures were completely determined by an extensive NMR analysis and comparison with NMR data of similar compounds for absolute stereochemistry of the side chain. The compounds were assigned as 5,8-epidioxy- (24S)-ethylcholesta-6,22(E),25-trien-3-ol(1), 5,8-epidioxy-(24S)-methylcholesta- 6,22(E)-dien-3-ol(2), 5,8-epidioxycholesta-6,22(E)-dien-3-ol(3) and 5,8- epidioxycholesta-6-en-3-ol (4).

• Journal of the Korean Magnetic Resonance Society
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• v.17 no.1
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• pp.47-53
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• 2013

Four new cyclic peroxide compounds (1~4) were isolated from the marine sponge Plakortis simplex. Their structures including relative stereochemistry were determined by MS and NMR analysis. All compounds, a side carbon chain with 10 carbons, were very unstable. After transformation into methyl ester analogues, the structure determination was conducted. Compounds 1a and 2a are stereoisomers, assigned as $3S^*$, $4S^*$, $6R^*$ and $3R^*$, $4S^*$, $6R^*$, respectively. Similarly, compounds 3a and 4a, replaced the methoxy group with an aliphatic methyl, are also stereoisomers. Compounds 1a and 2a exhibited the strong antifungal effect against the fungus Candida albicans.

• Journal of the Korean Magnetic Resonance Society
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• v.21 no.4
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• pp.145-151
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• 2017

Rhodiola rosea, also known as gold root or rose root, is a perennial plant in the family of Crassulaceae. The rhizhome of R. rosea has been widely used as a hemostatic, tonic for burns and contusions in traditional Chinese medicine. Recent studies reported its strong antioxidant and adaptogenic properties. In this paper, we attempted to isolate compounds from the methanolic extract of R. rosea rhizomes. Four compounds including one new compound (1), two kaempferol glycosides (3 and 4) were isolated from chloroform and ethyl acetate soluble fraction of R. rosea extract. The structures of 1~4 including relative stereochemistry were determined by MS and NMR analysis.

• Journal of the Korean Magnetic Resonance Society
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• v.2 no.2
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• pp.152-157
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• 1998

The diversity of RNA functions ranges from storage and propagation of genetic information to enzymatic activity during RNA processing and protein synthesis. This diversity of functions requires an equally diverse arrays of structures, and, very often, the formation of functional RNA-protein complexes. Recognition of specific RNA signals by RNA-binding proteins is central to all aspects of post-transcriptional regulation of gene expression. We will describe how NMR is being used to understand at the atomic level how these important biological processes occur.

• Journal of the Korean Magnetic Resonance Society
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• v.11 no.2
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• pp.122-128
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• 2007

Three sterol sulfates were isolated from AMPK activity-guided fraction of a marine sponge Acanthodoryx fibrosa. Their structures were determined by an extensive NMR analysis, MS data, and two compounds were confirmed as unusual phosphorylated sterol sulfates by comparing with NMR data of the known compounds. Compound 3 was given to be a new dephosphated sterol sulfate derivative. Compound 1 moderately showed AMPK activation effect on L6 myoblast cell through Western blot analysis.

• Journal of the Korean Magnetic Resonance Society
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• v.24 no.2
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• pp.47-52
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• 2020

Liquid-liquid phase separation (LLPS) of biomolecules, a newly-found phase behavior of molecules in the liquid phase, has shown to its relationship to various biological function and misfolding diseases. Extensive studies have increasingly revealed a general mechanism of LLPS and characterized the liquid droplet; ho wever, intermolecular interactions of proteins and structural states of LLPS-inducing proteins inside of the droplet remain largely unknown. Solution NMR spectroscopy has emerged as a powerful approach as it provides invaluable information on protein intermolecular interactions and structures at the atomic and residue level. We herein comprehensively address useful techniques of solution NMR including the effect of paramagnetic relaxation enhancement for the study on the LLPS and droplet based on recent studies.

• International Journal of Concrete Structures and Materials
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• v.7 no.2
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• pp.165-174
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• 2013

Portland cement concrete exposed to high temperatures during mixing, transporting, casting, finishing, and curing can develop undesirable characteristics. Applicable requirements for such the hot weather concrete differ from country to country and government agencies. The current study is an attempt at evaluating the hardened properties of the concrete exposed to hot weather in fresh state. First of all, this study reviews the current state of understanding and practice for hot weather concrete placement in US and then roadway sites with suspected hot weather concrete problems were investigated. Core samples were obtained from the field locations and were analyzed by standard resonance frequency analysis and the boil test. Based on the results, there does not appear to be systematic evidence of frequent cracking problems related to high temperature placement. Thus, the suspicious deteriorations which are referable to hot weather concreting would be due to other factors.

• Proceedings of the KSPS conference
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• 2007.05a
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• pp.221-224
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• 2007

It is reported that the orthognathic patients suffer from not only aesthetic problems but also resonance disorder and articulation disorder because of the abnormality of the oral cavity. These disorders have an influence on the patients' communication and they are usually required to be corrected by orthognathic surgery. Speech of the orthognatic patients is affected by the change of the oral cavity capacity and structures after surgery. This study was designed to investigate the resonance of nasality and the intelligibility of speech for acoustic characteristics of speech for pre and post orthognatic surgery patients.