• Journal of Pharmaceutical Investigation
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• 제31권2호
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• pp.119-123
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• 2001

Six polymorphic modifications of Balofloxacin (Q-35) were obtained by the recrystallization from different organic solvents and characterized by differential scanning calorimetry (DSC), X-ray powder diffraction (XRPD). The dissolution patterns of these six modifications were also checked in distilled water at $37{\pm}0.5^{\circ}C$, 50 rpm for 60 minutes. The polymorphic modifications showed significant differences in the dissolution rate. The dissolution rate of Mod. 1 was faster than that of other polymorphic modifications. The transformation during storage was also studied.

• Journal of Pharmaceutical Investigation
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• 제32권2호
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• pp.81-85
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• 2002

Three polymorphic modifications of CKD-602, water soluble derivative of camptothecin, were obtained by the recrystallization from different organic solvents and characterized by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and X-ray powder diffraction (XRPD). The major endothermic peaks of the DSC curve of Form 1, Form 2 and Form 3 was shown at $268.71^{\circ}C$, $247.83^{\circ}C$, $244.76^{\circ}C$, respectively. Form 2 was elucidated to be an acetic acid solvate and Form 3 was elucidated to be a methanol solvate. The dissolution patterns of these three modifications were also checked in distilled water at $37{\pm}0.5^{\circ}C$, for 30 minutes. The polymorphic modifications showed differences in the dissolution rate. The dissolution rate of Form 1 was faster than that of other polymorphic modifications. When stored at different relative humidity over the period of 3 months, all of the polymorphic modifications did not undergo transformation.

• Bulletin of the Korean Chemical Society
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• 제30권10호
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• pp.2265-2268
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• 2009

Terahertz time domain spectroscopy (THz-TDS) is applied in transmission to identify the five forms of modifications of furosemide and one commercial product from 0.3 THz to 1.6 THz at room temperature. The different absorption spectra of the different forms are sensitive to crystal structures. Density function theory (DFT) calculation was used to understand the vibrational modes of furosemide in the THz region. X-ray powder diffractometry (XRPD) was applied to confirm the different forms of modifications. The results demonstrate that THz-TDS is a potential analytical technique in investigating polymorphic forms in the pharmaceutical fields.

• Bulletin of the Korean Chemical Society
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• 제23권1호
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• pp.35-40
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• 2002

Photoreaction of guest organic anions in layered organic-inorganic hybrid materials was investigated. The layered hybrids were synthesized by an anion-exchange reaction of $[LiAl_2(OH)_6]Cl{\cdot}yH_2O$ layered double hydroxide with aqueous (Z,Z)- and (E,E)-muconates under inert atmospheric condition, to give new organicinorganic hybrids of $[LiAl_2(OH)_6]_2[(Z,Z)-C_6H_4O_4]{\cdot}zH_2O$ and $[LiAl_2(OH)_6]_2[(E,E)-C_6H_4O_4]{\cdot}H_2O$, respectively. The basal spacings calculated by XRPD of intercalates indicate that muconate anions have almost vertical arrangements against the host $[LiAl_2(OH)_6]^+$ lattices in the interlayer of organic-inorganic hybrid materials. When UV light was irradiated on the suspension of $[LiAl_2(OH)_6]_2[(Z,Z)-C_6H_4O_4]{\cdot}zH_2O$, the (Z,Z)-muconate anions of the gallery space of hybrids were polymerized in the aqueous media while it was isomerized into more stable (E,E)-muconate in the methanollic suspension in the presence of catalytic amount of molecular iodine. All the products were characterized using elemental analysis, TGA, XRPD, FT-IR, $^1H$ NMR and $^{13}C$ CP-MAS NMR.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2005년도 INTERNATIONAL SYMPOSIUM ON SOIL & GROUNDWATER ENVIRONMENT
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• pp.199-200
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• 2005

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2005년도 INTERNATIONAL SYMPOSIUM ON SOIL & GROUNDWATER ENVIRONMENT
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• pp.55-57
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• 2005

• 한국결정학회:학술대회논문집
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• 한국결정학회 2002년도 정기총회 및 추계학술연구발표회
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• pp.28-28
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• 2002

The hydrothermal reaction of Ni(NO₃)·6H₂O with 4.4'-oxybis(benzoic acid) (OBCH₂) and trans-1,2-bis(4-pyridyl)ethylene (bipyen) led to the formation of a 3-dimensional coordination polymer with the empirical formular of [Ni(OBC)(bipyen)]·H₂O. The complex has been characterized by X-ray diffraction, elemental analysis, TGA, IR, X-ray power diffraction (XRPD), It crystallized triclinic space group P1 with a = 9.280(2)Å., b = 11.317(4) Å, c = 12.442(3) Å, Z = 2, R (ωR₂) = 0.0346 (0.0846).

• Bulletin of the Korean Chemical Society
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• 제33권6호
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• pp.1929-1933
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• 2012

Two cobalt(II) compounds $[Co(2,2{^\prime}-bipy)(H_2O)_2(SO_4)]_n$ (1) and $[Co_2(2,2^{\prime}-bipy)_2(btec)(H_2O)_6]{\cdot}2H_2O$ (2) (2,2'-bipy = 2,2'-bipyridine, $H_4btec$ = 1,2,4,5-benzenetetracarboxylic acid), have been simultaneously synthesized by a one-pot slow solvent evaporation reaction. Their structures were determined by single-crystal X-ray diffraction and further characterized by X-ray powder diffraction (XRPD), IR, elemental and thermogravimetric analysis (TGA). The structural analysis reveals that compound 1 exhibits an infinite 1D chain structure with the octahedral Co(II) centers bridging by the tetrahedral ${\mu}_2-SO{_4}^{2-}$ ligands, while compound 2 possesses a dinuclear $Co_2(2,2^{\prime}-bipy)_2(btec)(H_2O)_6$ unit and the two adjacent octahedral Co(II) ions are linked by the bismonodentately coordinated btec ligand. Additionally, compound 2 exhibits blue fluorescent emission in the solid state at room temperature.

• 공업화학
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• 제27권1호
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• pp.16-20
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• 2016

본 연구에서는 $TiO_2$/마이카 혼성 복합 재료의 합성과 적외선 반사 특성에 관한 연구를 수행하였다. 마이카 입자의 존재 하에 아세트산 수용액에서 titanium isopropoxide의 가수 분해 반응과 축합 반응에 의해 $TiO_2$/마이카 복합 재료를 합성하였다. $TiO_2$/마이카 복합 재료의 열처리($600{\sim}1000^{\circ}C$, 1~3 h)에 의해 마이카 표면에 형성된 비결정성 상의 $TiO_2$은 anatase 상을 거쳐 결정성 rutile 상으로 전환되었으며 열처리 조건에 의해 결정의 크기가 제어되었다. FE-SEM 분석, ED-XRF 분석, XRPD 분석을 통하여 마이카와 $TiO_2$/마이카 복합 재료의 물리화학적 특성을 규명하였다. 확산 반사-근적외선 분광 분석을 통하여 측정한 $TiO_2$/마이카 혼성 복합 재료의 근적외선 범위(780~2,500 nm)에서의 일사 반사율은 88.6%로, 순수한 소성 마이카의 86.6%보다 다소 높았다. 따라서 $TiO_2$/마이카 혼성 복합 재료는 높은 광반사율을 나타내는 차열 도료의 안료로 사용할 수 있을 것이다.