• Elastomers and Composites
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• 제50권1호
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• pp.35-48
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• 2015

Polyhedral oligomeric silsesquioxane (POSS) is an important inorganic-organic hybrid material with a three-dimensional structure. Polyurethane (PU) is a widely applied polymer that has versatile properties with the change of two phase structure. When POSS is incorporated into PU by physical or chemical methods, many properties can be greatly improved, such as mechanical properties, thermal stability, biodegradation resistance, and water resistance. This paper reviews the recent progress in preparation, structure, and performance of POSS-modified polyurethane from the viewpoint of physical blending and chemical modification.

• 한국식품과학회지
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• 제29권6호
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• pp.1304-1308
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• 1997

충치 예방물질의 지속적인 연구로 Jack Fruit 잎으로부터 새로운 procyanidin류를 분리하였고 thiolysis 및 기기 분석에 의해 구조를 결정하였다. 신규화합물의 화학 구조는 flavan-3-ol 화합물의 삼량체인 $(-)-epiafzele-chin-(4{\beta}{\rightaroow}8)-afzelechin-(4{\alpha}{\rightaroow}8)-catechin$의 구조로, 분자량이 $833\;[M-H]^-$ 이었다. 화학 구조가 결정된 신규화합물의 glucosyltransferase저해 실험 결과 1.0 mM에서 완벽한 저해 효과가 관찰되었고 저해기작은 비경쟁적 저해제임을 알았다.

• Bulletin of the Korean Chemical Society
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• 제35권9호
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• pp.2839-2842
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• 2014

• Bulletin of the Korean Chemical Society
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• 제34권4호
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• pp.1278-1281
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• 2013

• Bulletin of the Korean Chemical Society
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• 제34권10호
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• pp.2861-2862
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• 2013

• Bulletin of the Korean Chemical Society
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• 제33권11호
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• pp.3827-3830
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• 2012

• Bulletin of the Korean Chemical Society
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• 제23권6호
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• pp.903-907
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• 2002

• Bulletin of the Korean Chemical Society
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• 제18권5호
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• pp.473-474
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• 1997

• Bulletin of the Korean Chemical Society
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• 제33권9호
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• pp.2917-2924
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• 2012

Four novel metal-organic complexes $[Cd_2(IP)_2(TBZ)_2(H_2O)_2]{\cdot}(H_2O)$ (1), $[Zn_4(IP)_4(TBZ)_4]{\cdot}2(H_2O)$ (2), $[Zn_2(BTC)(TBZ)_2(CO_2H)]$ (3), [Co(PDC)(TBZ)] (4) (where IP = isophthalate; TBZ = thiabendazole; BTC = 1,3,5-benzenetricarboxylate; PDC = pyridine-3,4-dicarboxylate) have been prepared and characterized by IR spectrum, elemental analysis, thermogravimetric analysis, and single-crystal X-ray diffraction. X-ray structure analysis reveals that 1, 2, and 3 are one-dimensional chain polymers, while 4 is a two-dimensional network polymer. The TBZ acts as a typical chelating ligand coordinated to the metal center in all complexes. The 1D chain architecture of 1 is constructed from isophthalates and cadmium atoms. A simultaneous presence of chelating, monodentate and bidentate coordination modes of IP ligands is observed in complex 2. In complex 3, the 16-membered rings are alternately arranged forming an infinite 1D double-chain structure. The 2D skeleton of 4 is formed by cobalt ions as nodes and PDC dianions as spacers, through coordination bonds. The hydrogen bonds and ${\pi}-{\pi}$ stacking play important roles in affecting the final structure where complexes 1 and 3 have 2D supramolecular networks, while complexes 2 and 4 have 3D supramolecular architectures.

• Bulletin of the Korean Chemical Society
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• 제34권9호
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• pp.2737-2740
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• 2013

The layered $KTiNbO_5$ was successfully synthesized with titanium(IV) isopropoxide and niobium oxalate by a novel polymerized complex (PC) method. The morphology and structure of the as-prepared sample was characterized by means of High-Resolution Transmission Electron Microscope, powder X-ray diffraction, and Laser Raman Spectroscopy. The spectral response characteristic was recorded by using UV-vis Diffuse Reflectance Spectroscopy. Results show that $KTiNbO_5$ as-prepared by PC method presents an uniform morphology of nano-particles, the mean particle sizes is ca. 28 nm corresponding to the (002), and the crystal structure can be well indexed to the orthorhombic phase. The sample as-prepared by PC method has higher band gap energy than that of the sample prepared by a solid-state reaction method due to the quantum size effect.