• 한국세라믹학회지
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• 제53권4호
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• pp.406-410
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• 2016

Carbon-coated sodium iron pyrophosphate ($Na_2FeP_2O_7$) was prepared by a simple and low-cost pyro-synthesis route for further use as the cathode for Na-ion batteries. The X-ray diffraction (XRD) pattern of the sample annealed at $650^{\circ}C$ confirmed the pure triclinic phase of $Na_2FeP_2O_7$. Electron microscopy studies revealed a cross linked plate shape morphology of the $Na_2FeP_2O_7$ sample. When tested for application in Na-ion battery, the $Na_2FeP_2O_7$ cathode showed two redox pairs in the potential window of 2.0-4.0 V. The cathode registered initial discharge and charge capacities of 80.85 and 90 mAh/g, respectively, with good cycling performance.

• Journal of Photoscience
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• 제9권2호
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• pp.356-358
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• 2002

Regioselective 3$^1$-$^{18}$ O-labelling of chlorophyll derivatives possessing a 3-formyl group such as methyl (pyro) pheophorbide-d (3, 4) was carried out efficiently by a simple one-step procedure; by stirring a homogeneous solution of tetrahydrofuran and H$_2$$^{18}$ O containing a small amount of trifuluoroacetic acid.

• Rapid Communication in Photoscience
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• 제1권1호
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• pp.19-20
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• 2012

Novel star-shaped imide compounds containing electron-donating triphenylamine and/or electron-withdrawing bis(trifluoromethyl)phenyl side groups were synthesized via a two-step process. First, 3,6-dibromo-benzene-1,2,4,5-tetracarboxylic acid (2B4BA) was reacted with 4-aminophenyl (diphenylamine) (ATPA) or 3,5-bis(trifluoromethyl)aniline (6FA) by imide reaction. Then, Suzuki coupling reaction was carried out on these compounds with 4-(N,N-diphenylamino)-1-phenyl boronic acid (BTPA) or 3,5-bis(trifluoromethyl)phenyl boronic acid (6FBB), resulting in 3,6-bis[4-(diphenylamino)phenyl]-N,N'-bis[4-(diphenylamino) phenyl]-pyromellitimide (TPTPPI), 3,6-bis[3,5-bis(trifluoro methyl) phenyl]-N,N'-bis[3,5-bis(trifluoromethyl) phenyl]-pyro mellitimide (6F6FPI) or 3,6-bis[4-(diphenylamino)phenyl]-N,N'-bis[3,5-bistrifluoromethyl)phenyl]-pyromellitimide (6FTPPI). The imide compounds obtained were characterized by NMR, FT-IR, DSC, TGA, melting point analyzer, EA, and solubility measurements. In addition, their optical and electrical properties were evaluated by fluorescence spectroscopy, UV-vis spectroscopy, and cyclic voltammetry (CV). 6F6FPI exhibited deep blue emission (443 nm), along with high $T_m$ ($382^{\circ}C$) and relatively high $T_g$ ($148^{\circ}C$).

• 한국항공우주학회지
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• 제41권10호
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• pp.827-832
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• 2013

극초소형 위성으로 분류되는 큐브위성의 경우, 1U를 기준으로 $10cm{\times}10cm{\times}10cm$의 크기, 1kg 이하의 중량제한을 비롯해 폭발식 구속분리장치의 적용이 불가한 설계요구조건으로 인하여 열선 작동시 나일론선의 절단과 함께 구속을 해제하는 구속분리 방식이 일반적으로 적용되고 있으나 낮은 체결력과 다수 구조물의 구속 시 다수의 열선 적용을 필요로 하는 등 시스템 복잡화의 단점이 존재한다. 본 논문에서는 기존의 큐브위성에 적용되는 열선 절단방식의 단점을 극복하기 위하여 열선절단방식을 적용한 분리너트형 비폭발식 구속분리장치를 고안하였으며, 인증모델의 기능시험, 정하중시험 및 충격시험을 통해 설계 유효성을 입증하였다.